US3405584A - Apparatus for electrically actuating a musical instrument - Google Patents

Description

Oct. 15, 1968 L. 1.. VON GUNTEN 3,405,534

APPARATUS FOR ELECTRICALLY ACTUATING A'MUSICAL INSTRUMENT Filed March 18, 1964 8 Sheets-Sheet 1 I NVEN TOR.

Lee L. Von Gunten g aze/W ATTORNEYS Oct. 15, 1968 .1 VON GUNTEN 3,405,584

APPARATUS FOR ELECTRICALLY ACTUATING A MUSICAL INSTRUMENT Filed March 18, 1964 8 Sheets-Sheet 2 I NVENTOR.

Lee L. Von Gumen MJMW ATTORNEYS Oct. 15, 1968 I L. L. VON GUNTEN 3,405,584

APPARATUS FOR ELECTRICALLY ACTUATING A MUSICAL INSTRUMENT Filed March 18, 1964 8 Sheets-Sheet 3 7/ f ifi Kiwi-12.2. 3 '1 g '75.

:75 Q l- 200 e k w I I '7 75 Z05 Z/On 00 Z Z02 I Q 4 20/ z \KQQQ X *5 g. QQ/ A! A! J INVENTOR.

' Lg L. Von Gunten ATTORNEYS Oct. 15, 1968 L. L. VON GUNTEN 3,405,584

APPARATUS FOR ELECTRICALLY ACTUATING A MUSICAL INSTRUMENT Filed March 18, 1964 8 Sheets-Sheet 4 I N VEN TOR.

Lee L. Von Gunten @uzdwy ATTORNEYS 5, 68 L. VON GUNTEN 3,405,584

APPARATUS FOR ELECTRICALLY ACTUATING A MUSICAL INSTRUMENT Filed March 18, 1964 8 Sheets-Sheet 5 w) INVENTOR.

Lee L. Von Gunien ATTORNEYS 1968 L.. 1.. voN GUNTEN 3,405,584

APPARATUS FOR ELECTRICALLY ACTUATI NG A MUSICAL INSTRUMENT Filed March 18, 1964 8 Sheets-Sheet 6 76 V V [I 21.

INVENTOR.

Le c; L. Von Gunten ATTORNEYS Oct. 15, 1968 L L. VON GUNTEN APPARATUS FOR ELECTRICALLY ACTUATING A MUSICAL INSTRUMENT 8 Sheets-Sheet 7 Filed March 18, 1964 INVENTOR. Lee L. Von Gunten BY ATTORNEYS Oct. 15, 1968 1.. VON GUNTEN 3,405,584

APPARATUS FOR ELECTRICALLY ACTUATING A MUSICAL INSTRUMENT Filed March 18, 1964 a Sheets-Sheet a w INVENTOR.

Lee L. Von Gunten ATTORNEYS United States Patent 3,405,584 APPARATUS FOR ELECTRICALLY ACTUATING A MUSICAL INSTRUMENT Lee L. Von Gunten, Buffalo, N.Y., assignor, by mesne assignments, to The Seeburg Corporation, Chicago, 11].,

a corporation of Delaware Filed Mar. 18, 1964, Ser. No. 352,813

16 Claims. (Cl. 84-147) ABSTRACT OF THE DISCLOSURE Anapparatus for automatically producing music in accordance with a pretedermined pattern of apertures in a movable music roll is illustrated. The perforation containing music roll is passed between sensing brushes and an electrically conducting contact roller. As the sensing brushes pass through perforations in the music roll, they engage the contact roller and complete a circuit to produce an electrical control signal. The electrical control signal determines the musical note to be played. An ex- ;pession control feature is obtained by means of an additional set of perforations in the music roll and a corresponding sensing and control circuit.

This invention relates to improvements in self-playing musical instruments, and more particularly a new and improved apparatus for electrically actuating a musical instrument such as a piano.

With the recent revival of interest in group singing, there is a definite need for self-playing musical instruments capable of automatic operation for providing the desired musical accompaniment. The present invention is designed to fulfill this need in an effective, etficient and economical manner, and is compact enough for use with the modern upright or vertical type of piano so popular today, although not limited thereto, while at the same time not interfering with normal manual playing of the piano.

A primary object of the invention is to provide apparatus including a new and improved note expression system adapted to automatically vary the tonal intensity of the music and thereby simulate the performance of an accomplished artist, and adapted to employ an expression control current lower than the higher note playing current required, and thereby avoid circuit overload.

Another object of the invention is to provide apparatus wherein the music roll is employed to control various au tomatic actions, and is provided with closely spaced or chain perforations for playing sustained notes, as opposed to long continuous perforations which are usually too fragile, and wherein the electrical sensor brush means is designed to maintain contact from one series of perforations to another so that the notes to be sustained do not flutter or repeat.

A further object of the invention is to provide apparatus wherein the music roll transport mechanism and sensor means are so arranged with respect to each other that the words printed on the music roll are exposed and plainly visible to persons standing or seated at or near the piano up until the moment the corresponding notes are played, thereby making it easy, pleasant and enjoyable to sing along with the musical accompaniment.

A still further object of the invention is to provide apparatus including new and improved means for automa- 3,405,584 Patented Oct. 15, 1968 tically moving the contact roller into and out of contact relationship with the sensor brush means at the proper time, and thereby eliminate undesirable threading of the music roll between the contact roller and the sensor means when inserting and removing the music roll.

Another object of the invention is to provide apparatus including new and improved transmission and clutch means for shifting and reversing'the drive between the music roll spool shaft and take up spool shaft and for permitting each shaft to free wheel and follow while the other shaft drives.

Still another object of the invention is to provide apparatus including new and improved means for automatically initiating the reroll cycle, but only after the contact roller is automatically moved out of contact with the sensor brush means in order to avoid damage to the music roll during the reroll operation.

A further object of the invention is to provide apparatus including new and improved means for automatically starting the motor and transmission rotating in the play direction merely by insertion of a music roll into operative position, while avoiding false starts when removing such roll.

A still further object of the invention is to provide apparatus which is so constructed and designed as to automatically shut itself off following the reroll cycle, or automatically replay and reroll continuously, as desired.

Another object of the invention is to provide apparatus which is so constructed and designed as to facilitate connection with the music roll and take up spool, without unnecessary delay.

Still another object of the invention is to provide apparatus which is so constructed and designed as to permit the use of damaged or special rolls by providing new and improved means for cancelling the marginal functions of such rolls which would otherwise undesirably actuate unwanted functions of the apparatus.

Additional objects and advantages will become apparent upon an examination of the following detailed description and the accompanying drawings, wherein:

FIG. 1 is a top plan view of a modern upright type of piano incorporating new and improved apparatus constituting a preferred embodiment of the invention for electrically actuating such piano;

FIG. 2 is a front elevational view of the piano and inventive embodiment of FIG. 1, with a lower portion of the piano frame being broken away to illustrate the solenoid means for actuating the piano actions;

FIG. 3 is an enlarged vertical sectional view taken generally along line 3-3 of FIG. 2, and illustrating in greater detail the location of the inventive embodiment, a piano key and action, and solenoid means for actuating su ch piano action;

FIG. 4 is a fragmentary sectional view taken generally on line 44 of FIG. 3 and illustrating the various supports for the inventive embodiment and sensor means thereof, portions of which are shown in phantom;

FIG. 5 is an enlarged, fragmentary top plan view of the left end portion of the sensor means and support illustrated in FIG. 4;

FIG. 6 is a front elevational view of a music roll spool carrying a music roll adapted for use with the present invention;

FIG. 7 is an enlarged vertical sectional view taken generally on line 77 of FIG. 5, and illustrating the l v 3 relationship between the contact roller, the music roll thereon and the sensor means incorporating single sensor brushes;

FIG. 8 is an enlarged fragmentary view of a portion of FIG. 7 and illustrating the manner in which the sensor brush bridges the gap between closely spaced perforations in the music roll to make the desired contact with the contact roller for playing sustained notes;

' FIG. 9 is a view similar to FIG. 8, but illustrating how the sensor brush is spaced out of contact with the contact roller by the longer bridge between other perforations spaced further apart for playing notes to be repeated;

FIG. 10 is a vertical sectional view taken generally on line 10--10 of FIG. 3 and illustrating the contact roller, take up spool, transmission-clutch mechanism, brake mechanism, the music rool spool supporting spindles (the music roll being removed), and various switches employed for automatic actuation;

FIG. 11 is an enlarged fragmentary horizontal section taken generally on line 11-11 of FIG. 10 and illustrating in greater detail the adjustable dummy spindle and shaft for supporting a music rool spool, and various switches and controls;

FIG. 12 is a fragmentary view of a portion of FIG. 11 and illustrating the far left position of the dummy shaft relative to the second automatic start switch during inserion of a music roll;

FIG. 13 is a view similar to FIG. 12, but in elevation to illustrate the far left position of the dummy shaft relative to the first automatic start switch during insertion of a music roll;

FIG. 14 is a fragmentary view similar to FIG. 12, but illustrating the intermediate position of the dummy shaft relative to the second automatic start switch while a music roll is in operative position;

FIG. 15 is a fragmentary view similar to FIG. 13, but illustrating the intermediate position of the dummy shaft relative to the first automatic start switch while a music roll is in operative position;

FIG. 16 is a fragmentary view similar to FIG. 14, but illustrating the far right position of the dummy shaft relative to the second automatic start switch when a music roll has been removed;

FIG. 17 is a view similar to FIG. 15, but illustrating the far right position of the dummy shaft relative to the first automatic start switch when a music roll has been removed;

FIG. 18 is an enlarged vertical sectional view taken generally on line 18-18 of FIG. 10, and illustrating the contact roller and its carriage in the upper inoperative position closing the carriage limit switch initiating the reroll cycle, and the cam for actuating the take up spool sensor switch.

FIG. 19 is an enlarged fragmentary vertical sectional view taken generally along line 19-19 of FIG. 10, illustrating the four equally spaced hooks on the take up spool for engagement with the ring on the lower flap of the music roll which is shown in phantom along with the contact roll (in its upper, inoperative position) and the music roll spool, and illustrating both the solid line and dotted line positions of the take up spool sensor arm for moving the cam and actuating the sensor switch of FIG. 18;

FIG. 20 is an enlarged fragmentary ventical view taken generally on line 20-20 of FIG. 10, and illustrating the music roll and spool, the take up spool, the contact roller and carriage and the belt drive for the carriage in the solid line operative position wherein the contact roller and music roll engage the sensor means, and in the dotted line inoperative position wherein the music roll and contact roller are out of engagement with the sensor means;

FIG. 20a is a fragmentary section taken generally on line 20a20a of FIG. 20, and illustrating the manner in which the belt rides in a pulley guide mounted on the contact roller carriage;

FIG. 21 is an enlarged fragmentary vertical section taken generally along line 21-21 of FIG. 10and illustrating the location of the drive motor and chain drive, and the electromagnetically operated brake mechanism for locking the right hand music roll spool spindle drive shaft in order to permit the contact roller and carriage to be automatically moved to the upper, inoperative position of FIG. 20, prior to initiation of the reroll cycle;

FIG. 22 is an enlarged fragmentary vertical sectional view of the transmission and clutching mechanism illustrated in FIG. 10, and showing the one-way overrunning clutch on the upper music roll spoolshaftandthe electromagnetic clutch on the lower take up spool shaft;

FIG. 23 is an enlarged vertical section taken on line 2323 of FIG. 22, and illustrating the engagement between the dog members on the take up spool driving shaft and on the de-energized magnetic clutch during the play cycle;

FIG. 24 is a schematic diagram of the entire electrical system for controlling the various functions of the inventive embodiment; v

FIG. 25 is an enlarged schematic view of the automatic expression system circuitry;

FIG. 26 is a view similar to FIG. 7, but illustrating dual sensor brushes;

FIG. 27 is a view similar to FIG. 8, but illustrates the manner in which the dual sensor brushes bridge the gap between closely spaced perforations for playing sustained notes, and

FIG. 28 is a view similar to FIG. 27 but illustrating how the dual sensor brushes are held out of contact by the longer bridge between other perforations for playing repeated notes.

APPARATUS Referring to the drawings, and particularly FIGS. 1 and 2, a typical modern upright spinet type of piano is illustrated therein, and includes a cabinet or casing generally indicated at 1. This casing includes the usual cover 2 for enclosing the various piano actions and strings struck thereby (shown in FIG. 3). The cover is provided with a central front recess or cut out portion 3, a pair of spaced upper front panels 4, a lower front panel structure 5 and a pair of cheeks 6 extending forwardly from each end of the cabinet. These cheeks 6 are supported at their front ends by means of the usual legs 7, and such cheeks are spanned by the usual key board 8 composed of 88 keys including the black keys 9 and the white keys 10.

The key board bed frame (shown in FIG. 3) is covered by lower front panel 11 and an upper rear cover composed of front panel 12 and a pair of spaced top panels 13. At its lower end, the lower front panel structure 5 of the piano is recessed to provide for the usual soft pedal 14 on the left, middle pedal 15 and sustaining or damper pedal 16 on the right. Panel structure 5 is also broken away at 17 to illustrate the solenoid mounting means and solenoid means for electrically actuating the various piano actions.

The top cover 2, spaced upper front panels 4 and spaced key board cover panels 13 partially enclose the preferred embodiment of the inventive apparatus generally indicated at 18, and which includes left and right control panels 19 and 20 positioned beneath cover 2 and adjacent the opposite inner ends of upper front panels 4. Mounted on the left control panel is an automatic-manual intensity control 21, an automatic off-replay selector control 22, a marginal cancel switch 23 and a pilot light L. Mounted on right control panel 20 are a manual start switch 25, a manual stop switch 26 and a manual reroll switch 27.

Referring to FIG. 3, the piano keys, actions, solenoid mounting means and solenoid means for actuating such piano actions will be described first. The bed frame for supporting the various keys of the keyboard is generally indicated at 28, being supported at its outer end on legs 7 and at its inner and on lower front panel structure 5. Each key such as 9 or 10 is pivotally mounted on the bed frame by means of a center pin 29 projecting upwardly from a boss 30 on the frame. At its front end, each key is guided by a front pin 31 extending upwardly from another boss 32 on frame 28. At its rear end, each key rests upon a suitable pad 33 on the frame, and is connected to its action, generally indicated at 34, by means of a capstan plate 35 secured to the top rear end of the key by a capstan screw 36. The capstan plate 35 is provided with a hollow grommet 37 receiving a sticker screw 38 suitably threaded into the upper end of a sticker or abstract 39, the latter being pivotally connected at its lower end to the front of the whip 40.

The whip is suitably connected to the hammer 41 of the action and upon actuation of a key 9 or 10 the sticker 39 causes the corresponding whip 40 to pivot about its rear end in a clockwise direction, as viewed in FIG. 3, thereby causing the hammer 41 to move to the right and to strike its corresponding string 42. At the same time, the whip causes the damper mechanism generally indicated at43 to momentarily move to the off position away from the string for proper sounding of the desired note. The aforedescribed structure and operation of the key and action are conventional and well understood by those skilled in the art. Likewise, if it is desired that the notes struck be sustained, the sustaining pedal 16, illustrated in FIG. 2, is depressed, and by suitable connection (not shown) to damper mechanism 43, holds the latter in the off position, in accordance with conventional practice.

Continuing with FIG. 3, the means for automatically actuating the actions 34 will now be described. Such means preferably includes the solenoid mounting means generally indicated at 44 and the solenoid means generally indicated at 45, energization of the later causing actuation of the action. This solenoid means and mounting means therefore are preferably of the type disclosed and claimed in my copending application Ser. No. 86,916 filed Feb. 3, 1961 and entitled Solenoid Means and Solenoid Mounting Means for Pianos, now Patent No. 3,126,783 and reference to such application may be had for a more detailed description thereof.

The solenoid mounting means 44 preferably includes an upright rear support panel 46 extending transversely of the juxtaposed whips 40 of the various actions 34 and bolted in this position to a hollow bar 47 in turn supported on cross frames such as 48 within each end of cabinet 1. Mounted on rear support panel 46, as also seen in FIG. 2, are front support panels 49, and to each of which are secured a plurality of vertically spaced and generally horizontal lower claimping bars 50. Each such bar is preferably channel-shaped in cross section and is provided with a plurality of suitable means such as screws 51 for fastening the bar to the front panel 49, and these screws are adjustable for varying the generally normal movement of the bar relativeto the panel and the clamping action of the bar with respect thereto.

At its upper end, panel 49 is provided with a horizontal and elongated shelf 52 extending transversely of the whips 40, such shelf being secured to the front face of panel 49 by any suitable means (not shown). Spaced below the shelf is an elongated upper clamping bar 53 which is arranged for movement generally normal to the shelf and is secured to panel 49 by suitable means such as screws 54, which screws are adjustable for varying the clamping action of the bar 53 with respect to shelf 52. Adjustably interposed between the shelf and the upper clamping bar are a plurality of juxtaposed guide members 55 (only one of which is shown). Each such guide member has its inner end clamped between the bar and shelf and its outer end protruding frontwardly therefrom and arranged longitudinally of and beneath the corresponding whip 40. The shelf 52 is also provided with a cushioning member 56 on its upper surface for supporting the striking portion of the solenoid means to be described below.

There are actually three solenoid means illustrated, and each includes a generally rectangular casing 57 provided at its lower rear end with one or more tongues 58 adjustably interposed between the upper flange of the corresponding lower clamping bar 50 and front support panel 49. Each casing 57 is also preferably provided with a lower guide means 59 at its front end for controlling the movement of a solenoid armature rod. Arranged within each casing is a solenoid coil means generally indicated at 60, and reciprocally mounted within such coil means is a vertically arranged armature 61 to which is connected an armature rod. Actually portions of three armature rods are shown, the longest being indicated at 62a, the one of intermediate length at 62b and the shortest at 62c. These armature rods reciprocate vertically through the corresponding upper and lower guide means 55 and 59, and are severally provided with laterally offset lower end portions 63a, 63b and 630, respectively, which are suitably secured to the various armatures 61, as well as inturned upper end portions 64a, 64b, and 640 respectively (64a only being shown), each of which is provided with a resilient striking member 65 resting upon the cushioning member 56.

As described in detail in my aforesaid copending application Ser. No. 86,916, the staggered arrangement of the solenoid means in several horizontal rows, including the variation in length of the armature rods, permits the various striking heads 65 to be located in juxtaposition and severally alined with their respective whips, such as 40. Upon energization of solenoid means 45, the striking member 65 therefore rnoves upwardly and causes its corresponding whip 40 to pivot in a clockwise direction as viewed in FIG. 3 to actuate the hammer 41 of the action 34, just as when the piano key is actuated, as described above.

HOUSING Continuing with FIGS. 3 and 4, a pair of blocks 66 are suitably secured to the rear of front panel 12 and are provided with a pair of metal tongues 67 projecting toward each other and secured to the blocks by screws 68. In addition, a pair of blocks 69 are provided on cheeks 6 and are spanned by an elongated angle iron 70 secured thereto by screws 71 and the top surface of which is provided with a felt pad 72. The housing 73 of the inventive embodiment (FIG. 3) is designed to be supported by the metal tongues 67 and angle iron 70. This housing is composed of an upright wooden rear panel or wall 74 secured to the horizontal wooden bottom panel or wall 75, the front lower end of which is supported on flanges 67. The rear panel 74 is provided with an extension in the form of iron 76 which is supported on angle iron 70, the felt pad 72 being interposed to eliminate vibration noises.

As also seen in FIGS. 10 and 11, housing 73 is divided longitudinally into an elongated central chamber arranged between two smaller end chambers. The end chamber on the left is designed to enclose the various means for automatic starting of the apparatus, replay, reroll and shut off. This chamber is formed by an outer upright metal end wall 77 extending between cover 2 and bottom panel and provided with an inwardly turned rear flange 78 secured to rear wall 74 by screws 79. The inner end of the chamber is formed by an inner upright metal end wall 80 of the same type as outer end wall 77, being provided with inturned flange 81 secured to rear wall 74 by screws 82. The front of the left end chamber is closed by the metal control panel 19 which is provided with a pair of flanges '83 fitting over the front ends of walls 77 and 80 and secured in place by screws 84 (FIG. 11).

A similar chamber is formed at the right end of housing 73, and this chamber is designed to contain the transmission, clutch and brake mechanisms. It is formed by an outer upright end wall 85 having an inturned flange 86 secured to rear wall 74 by screws 87 and by an inner metal end wall 88 provided with a flange 89 secured by screws 90 to the rear wall. The front of this right end chamber is closed by control panel which is provided with a pair of flanges 91 fitting over the front ends of end walls 85 and 88 and suitably secured in place by screws 92 (shown in FIG. 21).

The elongated central chamber is, of course, closed at each end by the end walls 80 and 88 and is open at both the top and the front. This central chamber is designed to enclose the music roll or let off spool, the take up spool, and the contact roller and carriage to be described below. Referring back to FIGS. 1-4, the electrical sensor means is located directly in front of the central compartment and is at least partially covered by a metal plate 93 of L-shaped cross section, the lower leg of which rests upon front panel 12 (FIG. 3) and the upper leg of which is secured to the sensing device by screws 94 (FIGS. 1 and 2).

Transmission, clutch and brake mechanisms Continuing with FIG. 3 and also referring to FIGS. 10, 21, 22 and 23, the contents of the right end chamber will now be described. A reversible variable speed AC. motor M is suitably supported on the angle iron extension 76, and its output shaft 95 is provided with a small sprocket 96 for driving a chain 97 which, as illustrated in FIG. 21, passes through the cut out portion 98 in rear wall 74 of housing 73 in the right end compartment. Driven by the other end of the reach of chain 97, as best seen in FIG. 22, is a large sprocket 99 having a hub 100 on the outer end of which is mounted a small sprocket 101, the hub being journalled on hearing 102 fixed on the take up spool driving shaft 103 which passes freely through end wall 88. Shaft 103 is also provided with a stop collar 104 secured thereto by set screw 105. Adjacent the other end of sprocket 99 is a driving dog collar 106 secured on shaft 103 by set screw 107. As best seen in FIG. 23, collar 106 is provided with four projecting dog pins 108 equally spaced around its circumference, and during the play cycle, the collar 106 rotates in the direction of the arrow.

Referring to FIG. 22 the smaller sprocket 101 is. connected by a chain 109 to a larger sprocket 110 having a hub 111 journalled on a bearing 112 fixed on the music roll spool or let off spool driving shaft 113. The outer end of shaft 113 is suitably journalled in a bearing 114 provided in outer end wall 85 and at its other end the shaft is provided with an enlarged driving spindle 115 likewise journalled in a suitable bearing 116 in inner end wall 88. Shaft 113 is also provided with stop collars 117 and 119 adjustably fixed thereon by set screws 118 and 120 respectively.

Continuing with FIG. 22, the outer face of sprocket 110 is provided with a one way, over-running clutch 121 which is of conventional construction, being designed to free Wheel during the play cycle and to engage shaft 113 so that it may be driven in the opposite direction during the reroll cycle. The other end of sprocket hub 111 is provided with a smaller sprocket 122 which is connected by a chain 123 to a larger sprocket 124 fixed on a reciprocal dog member 125 which is journalled on non-magnetic shaft 103 and forms the movable pole of an electromagnetic or solenoid clutch generally indicated at 127. At its outer end, dog member 125 is provided with a projecting dog pin 126 which, as best seen in FIG. 23, is designed to engage one of dog pins 108 during the play cycle for driving take up spool shaft 103 through collar in the direction of the arrow. The magnetic clutch 127, which is suitably secured to inner end wall 88, includes the coil 128 and outer plate 129 through which dog member 125 reciprocates and a cover or housing 130 forming the other pole of the magnet, as well as acting as a bearing for shaft 103. A compression coil spring 131 normally biases dog member 125 into the engaged position shown for driving shaft 103 during the play cycle. The clutch 127 is energized to retract dog member 125 from the engaged position against the bias of spring 131 and thereby permit the let off spool shaft 113 to be driven through sprocket 100, chain 109 and engaged clutch 121 in the opposite direction during the reroll cycle, while shaft 103 free wheels and follows.

Referring to FIG. 21, the brake mechanism, which is designed to prevent rotation of shaft 113 just prior to the reroll cycle, includes a solenoid 132 suitably secured to outer end wall and provided with a reciprocal armature rod 133 pivotally secured at its outer end to a lower extension 134 on pawl 135 which is fixed on a rocker shaft 136 rotatably mounted in wall 85 at 137 (FIG. 10). A compression spring 138 is secured to rear wall 74 and to extension 134 on pawl 135 for normally biasing the pawl to its solid line position against stop 139. When momentarily energized, solenoid 132 retracts armature rod 133 to pivot pawl 135 to its dotted line position wherein the pointed end of the pawl engages the teeth of a ratchet wheel 140 fixed on shaft 113 by a set screw 141 (FIG. 22). When so engaged, shaft 113 is prevented from rotating, for a purpose to be described below.

Music roll and spool, take up spool and contact roller mechanisms Considering now FIGS. 6, 10, 11 and 18-20A, the contents of the central compartment will now be described. Referring first to FIG. 10, the music roll spool driving spindle 115 projects through inner end wall 88 and is axially alined with a dummy or idler spindle 142 reciprocal through opposite inner end wall 80. The music roll spool 143, illustrated in FIG. 6, is designed to be mounted on spindles 115 and 1 42. To this end, the spool 143 is provided with hollow right and left end flanges 144 and 145 respectively for receiving spindles 115 and 142 respectively. In accordance with conventional practice, both the spool end flanges and the spindles 115 and 142 are designed for releasable engagement with and for driving the music roll spool 143.

Continuing with FIG. 6, a paper music roll 146 is mounted on spool 143 and is provided with a number and variety of perforations 147 for playing the desired notes, as well as the words 148 corresponding to the notes. In addition, music roll 146 is provided with supplementary perforations 149 for controlling the expression of the notes played, and although not illustrated in FIG. 6, the music roll 146 is also provided with one or more perforations preferably located near the end of the roll, or at the end of each musical song thereon for initiating the reroll cycle. At its lower end flap the music roll 146 is provided with the usual catch or eyelet 150.

Returning to FIG. 10, the take up spool shaft 103 is suitably journalled in inner end walls 80 and 88 and supports the take up spool 151 which is provided with the usual right and left end flanges 152 and 153, respectively, as well as a central reduced portion 154.

As best seen in FIG. 19, a plurality of hooks or pins 155 are embedded in central reduced portion 154 of spool 151. These pins 155 are preferably four in number, equally spaced around the periphery of reduced portion 154 and are inclined in the direction of play rotation to facilitate engagement with eyelet on music roll 146.

Prior art player pianos normally have but a single hook for starting the music roll. The take up spool on a player piano rotates so slowly that if a user accidentally misses the hook when it passes, an aggravating waiting period is encountered while waiting for a single hook to make a complete revolution and rcassume a position suitable for connection with the music roll tab. By employing the preferably four equally spaced pins 155, the present inven tion completely overcomes this problem.

Continuing with FIG. 19, and as also seen in FIG. 10, a take up spool sensor arm or pin 156 is designed to rest in its lower solid line position within the groove forming central reduced portion 154 of the take up spool 151. This arm is provided with a collar 157 at its inner end fixed 9 on a shaft 158 which is suitably journalled in end walls 80 and 88. At its left end, as best seen in FIGS. 11 and 18, shaft 158 is provided with a cam 159 and forms the mechanical part of the control for the shutoff and replay functions, as will be explained in greater detail below.

Returning to FIG. 10, a hollow metal contact roller generally indicated at 160 is closed at each end, and is divided into a higher current note section 161 and a lower current note expression section 162 by an insulating mem her 163. At its right and left ends, contact roller 160 is provided with reduced shafts 164 and 165 suitably journalled in arms 166 and 167 respectively of an elongated U-shaped carriage completed by a cross bar 168. The carriage is held in the position shown by the right spacer collar 169 and the left spacer collars 170 journalled on take up spool driving shaft 103, and on the left end of which is mounted the stop collar 171 (shown in FIG. 18).

As illustrated in FIGS. and 18, the contact roller 160 and its carriage are located in the upper, inoperative position out of contact with the sensor means to be described below. As best seen in FIG. 10, the left end of cross bar 168 engages a front stop 172 in this upper, inoperative position.

Returning to FIG. 10, the left arm 167 of the contact roller carriage is provided with a lateral extension shaft 173 which, as shown in FIG. 18., passes through and freely oscillates along arcuate groove 174 in end wall 80. Shaft 173 forms the mechanical portion of the control for automatically initiating the reroll cycle.

Referring now to FIGS. 10, and 20A, the mechanical drive for automatically positioning contact roller 160 and its carriage will now be described. As best seen in FIGS. 20 and 20A, the rear end portion of right carriage arm 166 is provided with a fixedpulley guide generally indicated at 175, and which is composed of a pair of segmentally shaped plates 176 separated by a smaller segmentally shaped plate 177, each of these plates being secured together and to the outer surface of carriage arm 166 by screws 178. At its front end, carriage arm 166 is also provided with a fixed pulley 179, and trained over both guide 175 and pulley 179 is an endless rubber belt 180 of circular cross section. Belt 180 is also stretched over spacer collar 169 on shaft 103 and rides in a groove 181 provided in driving spindle 115. When in the solid line position illustrated in FIG. 20, the rear end of the contact roller carriage engages a rear stop 182, the music roll 146 and contact roller 160 being positively biased into electrical contact with the sensor means by the action of belt 180 which is driven by spindle 115 in a counterclockwise direction during the play cycle. At this time, the belt 180 is taut, and although free wheeling spindle 115 continues to be driven by the take up spool through the music sheet in a counterclockwise direction, belt 180 slips on the spindle.

At the end of the play cycle, or whenever it is desired to stop the music roll and go into the reroll cycle, the brake mechanism described above and referred to in FIG. 21, is momentarily actuated to prevent shaft 113 and its spindle 115 from moving. However, the take up spool shaft 103 continues to rotate in the direction indicated by the arrow in FIG. 23, causing the music roll or sheet 146 to become taut, maintaining engagement between ratchet 140 and pawl 135, and actually lift the contact roller 160 and pivot its carriage in a clockwise direction to the dot-ted line position of FIG. 20. The belt 180 does not interfere with this operation because spindle 115 is restrained against rotation, and during movement from the solid line to the dotted line position, the area enclosed by the belt is reduced, thereby eliminating unnecessary drag on the motor M and its transmission, as well as unnecessary wear on the belt. As the rear end of the carriage engages the front stop 172, the extension arm 173 (FIG. 18) moves to the upper position shown to initiate reroll cycle, whereupon electromagnetic clutch 127 (FIG. 22) is energized to disconnect dog members 125 and 106, and the direction of rotation of motor M is reversed to drive spindle 115, shaft 113 through engaged clutch 121 and belt 180 through spindle in the opposite direction (clockwise in FIG. 20), the slipping belt biasing carriage against the front stop 172, while the free wheeling take up shaft 103 and spool 151 thereon are reversely driven by spindle 115 through music roll 146.

When the reroll cycle has been completed, and it is desired to replay, clutch 127 is once again de-energized to engage the dog members and 106 (FIG. 22) the direction of rotation of motor M, spindle 115 and shaft 113 is reversed, clutch 121 overrunning, to drive belt 180 once again in a counterclockwise direction in FIG. 20, the belt pivoting and biasing contact roller and its carriage down to the solid line position for replay.

The aforedescribed automatic movement of the contact roller and its carriage away into and out of play position eliminates any manual threading of the music roll between the contact roller and sensor means when inserting a music roll 146. In addition, the automatic movement of the contact roller and its carriage into and out of play position completely eliminates any manual actuation or movement of either the contact roller and its carriage or the sensor means, as well as any possible damage to the music roll because it is moved well clear of the sensing mechanism prior to the reroll cycle. In addition, the action of the flexible belt in holding the contact roller 160 and its carriage, together with the music roll 146, firmly against the sensor means during the play cycle assures proper continuous playing of the notes corresponding to the perforations in the music roll, and the action of the belt during the reroll cycle insures that the contact roller and its carriage will remain in the desired upper, inoperative position during reroll. Moreover, when the apparatus is off and no music roll is in place, the belt 180 will maintain the contact roller and carriage in the upper inoperative position. Otherwise, the latter would pivot downwardly because the contact roller counterweights its carriage in this direction; Likewise, in moving from the dotted line position to the solid line position in FIG. 20, the belt 180 controls the downward pivoting movement of contact roller 160 and its carriage.

Automatic start, shut off and replay mechanisms Referring now to FIGS. 10, 11l7 and 18, the contents of the left end compartment will now be described. Considering FIG. 18 first, it will be noted that cam 159 on shaft 158 is designed to actuate the double pole, double throw take up spool sensor switch 183 which is suitably mounted on end wall 80, as also seen in FIG. 11. This operation occurs when the arm 156 (FIG. 19) drops down through the groove in take up spool 151 into contact with reduced portion 154, such as at the end of the reroll cycle wherein music roll 146 is about to leave the take up spool. Referring to FIGS. 10 and 18, when the extension shaft 173 on arm 167 of the contact roller carriage reaches the position shown in FIG. 18 closing the normally open carriage limit switch 184 to initiate the reroll cycle.

Referring to FIGS. 10, 11 and 12-17, the automatic starting mechanism will now 'be described. The idler or dummy spindle 142 for music roll spool 143 is designed to reciprocate through end wall 80 and in spindle housing 185 secured to end wall 80' by screws 186. Housing 185 is provided with an enlarged central bore 187 which forms a bearing for spindle 142 and terminates in a hollow extension 188 forming a bearing for the reduced spindle shaft 189, on the outer end of which is mounted an enlarged switch actuating head 190. A compression spring 191 normally biases spindle 142 and shaft 189 to the far right, wherein the inner face of head 190 abuts the outer end of hollow extension 88 on housing 185.

As best seen in FIGS. 10 and 11, a first music roll insert sensor switch 192 is arranged below housing 185,

1 l and is secured in position to the outer end of a Z-shaped bracket 193 by screws 194, the inner end of the bracket being secured by screws 195 to rear wall 74. A second music roll insert sensor switch 196 is arranged behind head 190, and is supported by an L-shaped plate 197 secured to rear wall 74 by screws 198.

Referring now to FIGS. 12-17, the structure producing the automatic starting function will now be described. Prior to insertion of the music roll spool 143 (FIG. 6), the head 190 and extension shaft 189 of dummy spindle 142 appear in the far right position shown in FIGS. 10, 16 and 17. Thus, the second sensor switch 196 is open, and the head 190 holds the first sensor switch 192 open to prevent energization of the motor M by the start-stop relay to be described below. As the music roll spool 143 is inserted by pushing the left end flange 145 over dummy spindle 142, this spindle and its extension shaft 189 and head 190 are moved to the far left position illustrated in FIGS. 12 and 13. In this position, head 190 engages and momentarily closes the normally open sensor switch 196 while being spaced from contact with the first sensor switch 192, which is permitted to close. Thus, both switches are closed, causing the motor M to be energized by the start-stop relay and drive the take up spool 151 in the play direction. Upon completion of the insertion operation by locating the right end spool flange 144 over driving spindle 115 (FIG. the head 190 and extension shaft 189 move to the right and remain in the intermediate position illustrated in FIGS. 14 and 15. In this position, the switch 196 is open because head 190 is out of contact therewith, while switch 192 remains closed because head 190 is also spaced therefrom. Thus, motor M drives the take up spool shaft 113 in the play direction, and the play cycle is begun by connecting the music roll 146 to the take up spool 151, as shown in FIG. 19.

Electrical sensor means Referring back to FIGS. 3, 4, 5 and 7, the electrical sensor means will now be described. As best seen in FIGS. 3-5, the bottom wall 75 of housing 73 is provided with a pair of longitudinally spaced brackets 200 of L- shaped cross section, the outwardly facing lower flange portions of which are secured to wall 75 by screws 201. These brackets 200 are traversed by a pair of elongated support rods 202 extending therethrough and suitably secured in place. Mounted on rods 202 is an elongated wooden block 203 of generally L-shaped cross section, its front upper leg portion (FIG. 7) being provided with a series of longitudinally spaced perforations 204. Suitably fastened to block 203 is an upright front plate 205 which is provided with a series of longitudinally spaced vertically elongated slots 206 corresponding in number to and alined with openings 204.

Snugly received in each of openings 204 is a hollow cylindrical shield 207 containing insulated lead wire 208. A shorter hollow cylindrical shield 209 is arranged adjacent shield 207, and into shield 209 are inserted a bunch of many fine wires making up a sensor brush 210. The sensor brush 210 is secured within shield 209 in any suitable manner, as by soldering, and the inner ends of the bunch of fine wires of the brush extend into the inner end of shield 207 and are crimped into electrical contact with lead wire 208 at 211.

It is to be noted that openings 204 are inclined upwardly and to the left, as illustrated in FIG. 7, to incline the shields 207, 209 and brush 210 in the same direction. However, each brush is bowed downwardly by the upper edge of slot 206 in plate 205 so that its outer end lies well below the horizontal diameter of contact roller 160, and is biased in the direction of rotation thereof during the play cycle. In addition, the outer end 212 of each brush 210 is preground concavely to conform to the convex contour of contact roller 160 and the portion of music roll or sheet 146 extending there- 12 around for intimate electrical contact with the contact roller.

It will be further noted in FIG. 7 that the sensor-means is located with respect to contact roller in the engaged position shown so that the entire sensor means is no higher than the horizontal diameter of the contact roller. With such an arrangement, the words, such as 148, on the music roll 146 (FIG. 6) are plainly visible to persons standing or seated at or near the front of the piano right up until the moment the corresponding notes are played. This arangement makes it easy, pleasant and enjoyable to sing along with the music being played.

Referring to FIGS. 8 and 9, it will be noted that the thickness of each brush 210 is such that the upper and lower individual wire make contact with the contact roller 160 through perforations 147s which are closely spaced by short bridges 146s for playing of notes intended to be sustained. These series of perforations are known as chain links and are designed to strengthen the paper music roll 146 against tearing, as opposed to the employment of elongated continuous perforations for sustained notes. At the same time, the sensor brush 210 is so designed as to present a contact area at its outer end which is greater than the bridge 146s separating each adjacent pair of perforations 147s, whereby continuous contact is maintained so long, as a particular note is intended to be sustained. Accordingly, there is no problem of fluttering or repeat sounds of sustained notes.

0n the other end, as illustrated in FIG. 9, perforations 1471, which are intended to play notes to be repeated, are more widely separated by the longer bridges 146r, and the total end contact area of each brush 210 is small enough to be separated or spaced from the contact roller 160 by each elongated bridge 146r to ensure proper sounding of notes intended to be repeated.

The brushes generally indicated at 210 in FIGS. 7-9 constitute a preferred embodiment. An alternative embodiment is illustrated in FIGS. 26-28, wherein like numerals indicate like parts. In this embodiment, each dual brush is composed of two vertically spaced decks, layers or bunches 214 each composed of many fine wires and separated adjacent their inner ends by a dual shield 213. These bunches are secured in place and in electrical contact with lead wires 208 in the same manner as described above, and at their outer ends 215, each bunch or group of wires forming a brush 214 is individually preground to present a concave end contact area conforming to the contour of the contact roller and portion of music roll 146 thereon. The two decks or groups of wires forming each brush 214 are so spaced from each other than when playing sustained notes, one deck may be riding on a bridge 146s while the other is in contact with the contact roller through a perforation 147s as illustrated in FIG. 27, and these groups present contact surfaces which together are larger than and span each bridge 146s for simultaneous engagement on each side thereof to ensure continuous contact as long as a note is to be sustained, just as does single brush 210. However, when repeated notes are to be played, the spacing between the decks of each brush 214 is such that both decks ride on the elongated bridge 146r between adjacent perforations 147r for properly playing repeated notes.

It is to be noted that in each of FIGS. 7-9 and FIGS. 27-28, the thickness of the preferably paper music roll 146 is exaggerated in order to clarify the illustration.

Referring now to FIGS. 5 and 24, the various contact brushes are generally indicated at 210. At the left end are the preferably five expression brushes 210e which are designed for contact through perforations 149 on music roll 146 (FIG. 6) and for controlling note expression, ranging from very soft to very loud, i.e. pianissimo, piano, moderato, forte and forte forte. The large group of brushes 21011 are designed to play the notes corresponding to perforations 147, and may be of any number desired, although preferably ranging from 64 to 84. At the far 13 right end of the note playing brushes 21011 is a reroll brush 2101- which is designed for initiating the reroll operation in response to one or more perforations (not shown).

Electrical system Referrin to FIG. 24, the overall electrical system is illustrated schematically. The usual 110120 volt A.C. line voltage is applied to plug 216, current flowing along hot or motor input side 217 through first music roll sensor switch 192 and second music roll sensor switch 196 connected in series therewith (when both are closed) through line 218 to AC. input terminal a of magnetic amplifier power supply 219. Current flows along the ground side 220 between plug 216 and A.C. input terminal b of the amplifier.

Returning to the hot side 217, current also flows through motor input line 221 and branch 222 to energize the coil of start-stop relay 223 which coil closes and locks its normally open pole 223p in closed position, the current returning to ground, i.e. motor output side through line 224, the normally closed manual off switch 26 and the normally closed delay relay pole 225p which are connected in series with the coil of relay 223.

When only switch 192 is closed, current flows through line 226'and closed pole 223p to illuminate grounded pilot light L, and through branch 230 to junction 231, the current flowing reversely through line 221 and branch 222 to maintain the coil of relay 223 energized. Pole 223p is connected in series with switch 192 and in parallel with switch 196 for this purpose. The current continues through input line 232 through the variable resistor type motor tempo control 24, also mounted on right control panel 20 (FIG. 2), to one field terminal 233 to motor M. Current also flows from the other field terminal 234 of the motor through line 235, closed reversing pole 236 b of reroll relay 236 when deenergized) and through line 237 into armature terminal 238, returning to ground from the other armature terminal 239,, through line 240, and closed reversing pole 236a of reroll relay 236. The flow of the current through the motor and reversing poles 236i) and 236a in the direction indicated causes the motor M to rotate and drive the transmission in the play direction.

Whenever a music 'roll 146 is in progress, either during the play cycle or reroll cycle, and the music roll 146 holds arm 156 out of reduced central portion 154 of take up spool 1'51 (i.e. dotted line position shown in FIG. 19), the double pole, double throw take up spool sensor switch 183 is held in the upper dotted line position in FIG. 24. Thus, current flows through branch 241 and pole 183a only when the contact roller carriage limit switch 184 is closed (such as at the end of a reroll cycle) and through branch 244 to energize the coil of reroll relay 236 and clutch solenoid 127, the reroll relay 236 moving its poles 236a, b, c and d from the upper solid line play 'position to the lower dotted line reroll position, wherein the current flow through poles 236b, 2360 and armature terminals 238, 239 is reversed to reverse motor M, and clutch solenoid 127 disengaging the motor drive to take up shaft 103.

When take up spool sensor switch 183 is up, current also flows through branch 242, pole 183b and line 246, when lock-in pole 236d of energized reroll relay 236 is in its lower ,dotted line position to maintain current to relay 236 and solenoid 127. In addition, current flows through shunt 243 when replay or shut off selector switch 22 is closed for shut oft" purposes when switch 183 drops down.

When take up spool sensor switch 183 does drop down to the solid line position, such as when the music roll .146 is about to leave take up spool 151 at the end of a reroll cycle (arm 156 dropping down to the solid line position of FIG. 19) current flows through branch 241, pole 183a and line 245 through the heater of thermal 14 delay relay 225 and lowered pole 236a of relay 236 to ground.

If selector switch 22 is open, no current will flow through branch 242 when sensor switch 183 drops to the solid line position and thus relay 236 and clutch solenoid 127 immediately become de-energized to permit automatic replay. However, if selecor switch 22 is closed, current to reroll relay 236 and clutch solenoid 127 will be m0- mentarily maintained through the closed locking pole 236d in its lower position until delay relay 225 opens its pole 225p, thereby opening the circuit to the start-stop relay 223 and shutting off the apparatus, such as at the end ofa reroll cycle.

Continuing with FIG. 24, the DC. circuitry will now be described. Direct current of low value flows from control voltage supply terminal e of amplifier 219 through line 247, left end section 162 of contact roller 160, expression brushes 2102 engageable therewith through expression perforations 149 (FIG. 6) on music roll 146 and lead wires 208e and parallel resistance R R R R and R returning through normally closed pole 23a of double pole double throw marginal cancel switch 23 and return line 248 to terminal f of magnetic amplifier 219. Should it be desired to manually control the expression of the notes being played, the variable resistor control generally indicated at 21 may be employed. This is accomplished by moving the double pole throw marginal cancel switch 23 into the dotted line position, opening pole 23a, and manually varying the control 21 to control the current flowing in the control circuit between terminals e and 1, whereas when switch 23 is in the solid line position, such control is automatic through resistances R R and brushes 210e in the expression circuit, which is connected to terminals 2, 1, intermediate A.C. input terminals 11, b and D.C. output terminals 0, d.

As best seen in FIG. 25, the automatic expression control circuit controls the output at c, d of amplifier 219 through the grounded control winding 249 connected in series by line 248 to the parallel resistors R -R of varying value and individually connected in series with control brushes 2102. Thus, when a perforation 149 in the travelling music sheet 146 permits contact between an expression brush 2102 and the contact roller section 162, one of the resistances R R is connected between the control voltage supply line 247 and control winding 249 of magnetic amplifier 219, The resistance so selected by any of the several automatic expression channels selectively adjusts the magnetic amplifier control winding current which produces a desired value of reset magnetometive force. As also seen in FIG. 24, this current acts to adjust the value of the output voltage in line 250 to the banks of note playing solenoid means 45 through section 161 of contact roller and the individual note contact or sensor brushes 210n engageable therewith through note perforations 147, the current returning through ground line 251.

In this manner, a magnetic amplifier control current of only a fraction of an ampere controls the volt-age of the output capable of several amperes of current necessary to play the piano with the solenoid means 45. This control current is always significantly lower than that required to energize just one solenoid means 45 in the note playing circuit, and thus overloading of the control circuit is effectively avoided.

Moreover, the automatic expression control circuit above described effectively raises and lowers the output of magnetic amplifier 219 automatically so that solenoid means cause the notes to play in varying degrees of loudness to give striking realism to the sound of the music, simulating the performance of an accomplished artist. More specifically, such control circuit automatically produces crescendos, diminuendos, note accents and delicate shadings of tonal intensity, just as the artist does manually, and all of which is generally referred to herein as automatic expression.

Continuing with FIG. 24, an automatic reroll brush 210r is also provided, and at the end of the play cycle, the music roll 146 is provided with a perforation (not shown), permitting the reroll circuit to be completed through engagement with roller section 161, the current flowing through line 252 to the normally closed lower pole 23b of marginal cancel switch 23, line 253 and line 254 to energize the carriage left brake solenoid 132 which fixes the upper music roll spindle shaft 113 against rotation, as described above. As will also be evident, a manual switch 27 may be closed at any time during the play cycle to initiate the reroll cycle, and the opening of marginal cancel switch 23 will cut out the reroll function.

OPERATION Upon insertion of a music roll spool 143 carrying a music roll 146, the apparatus is automatically started in the following manner. The head 1% of dummy spindle 142 is first moved from the position of FIGS. 1-6 and 17 to the positions of FIGS. 12 and 13, thereby closing both\ the first and second music roll sensor switches 192 and 196 simultaneously. As this occurs, the start stop relay 223 (FIG. 24) is energized to close its pole 223p and remain locked in position to provide current through line 226 so long as first sensor switch 192 remains closed. Upon completion of the music roll insertion operation, head 190 moves to the position illustrated in FIGS. 14 and 15, wherein the momentarily closed second sensor switch 196 is opened but the first sensor switch 192 remains closed. Thus, current flows through the locked in pole 223p of relay 223 through branch 230, and line 232, motor tempo control 24 and motor M, the direction of current flow through the armature being from line 237 into one armature terminal 238 and out from the other armature terminal 239 through line 240 and reversing pole 236c (solid line position) to ground. Thus, the motor M through the transmission illustrated in FIG. 22 drives the take up spool shaft 103 in the play direction wherein one of the dogs 108 is engaged by the dog 126 and rotate in the direction of the solid line arrow (FIG. 23), the clutch 127 being de-energized and the music roll spindle shaft 113 free wheeling and not being driven at all at the moment.

In order to initiate the play cycle, the operator pulls out the lower end of the music roll 146 and connects ring 150 to one of the pins or catches 155 on the rotating take up spool 151, as illustrated in FIG. 10. This operation is facilitated by the use of the four equally spaced pins 155 to avoid any undesirable delay in connecting the music I011 146 to take up spool 151, and since the contact roller 160 is in the upper inoperative position illustrated in dotted lines in FIG. 20, there is no problem of threading the music roll between the contact roller and the sensing mechanism.

As soon as such connection is made, the music roll 146 drives spindle 115 in a counterclockwise direction in FIG. 20, spindle 115 driving belt 180 and pivoting contact roller 160 and its carriage down to the solid line position into contact with the various sensor brushes 210 (or 214) The slipping belt 180 continues to urge the contact roller 160 in the downward direction and maintains it in the desired position wherein the rear of the carriage engages rear stop 182.

As this power positioning of the contact roller 160 into play position occurs, the music roll 146 is wound upon take up spool 151 and elevates arm 156 to the dotted line position shown in FIG. 19. As a result, take up spool sen- 16 sor switch 183 is moved to the upper or dotted line position of FIG. 24 by the cam 159 on shaft 158 on which arm 156 is mounted (FIG. 18). In the upper position, switch 183 enables branch circuits 241 and 242 for completion later on. .4

During the play cycle the lower current in the automatic expression control circuit and control winding 249 in FIGS. 24 and 25, controls the D.C. output of amplifier 219 to the banks of solenoid means 45 for actuating the actions 34 illustrated in FIG. 3, and playing the various notes corresponding to the perforations 147 in music roll 146. Thus, the expression brushes 210e (or 214e) need not carry the heavier current required for energizing solenoid means 45 to play the notes.

Automatic reroll At the end ofthe play cycle, the music roll 146 is provided with a perforation (not shown) permitting the D0. circuit (FIG. 24) to be completed through reroll brush 2101" (or 214r) and thereby energize the carriage lift brake solenoid 132. Upon such energization, which is automatic when initiated by the reroll perforation in the music roll, or which can be manually accomplished at any time during the play cycle by momentarily closing switch 27 on control panel 20 (FIGS. 2 and 24), the armature rod 133 (FIG. 21) is retracted to engage pawl 135 with the teeth of sprocket wheel on shaft 113. This immediately stops rotation of shaft 113, its spindle 115 and the music roll spool 143 thereon while the take up spool spindle 103 continues to drive in the play direction.

As also seen in FIG. 20, the music roll 146 is immediately made taut and to assume a position approaching a straight line as representing the shortest distance between the music roll spool 143 and take up spool 151. Likewise any slack in the music roll 146 on or between these spools is taken up at this time. During this process, the contact roller is forced upwardly to the dotted line position of FIG. 20 (it cannot go downwardly because of stop 182), and literally walks up the inside surface of the music roll 146.

While brake solenoid 132 of FIG. 21 is only momentarily energized, the music roll 146 urges the ratchet wheel 140 into engagement with the pawl 135, and thereby maintains the pawl in the dotted line position against the bias of spring 138, until the carriage limit switch 184 in FIG. 24 is closed by the extension shaft 173 on carriage arm 167, as illustrated in FIG. 18. At this point, current flows through line 244 (FIG. 24), simultaneously energizing reroll relay 236 and clutch solenoid 237. The reroll relay immediately moves its poles 236a-236d down from the solid to the dotted line position, whereby the current flow to the armature of motor M is reversed through reversing poles 23611 and 2361:. At the same time, clutch 127 is energized to retract dog member 125 (FIG. 22), out of engagement with dog collar 106 on take up spool shaft 103. As an immediate result, the direction of rotation of motor M is reversed, and the upper music roll spindle 115 and shaft 113 are positively driven through engaged clutch 121 to initiate the reroll operation.

Automatic shut 0]? 0r replay At the end of the reroll cycle, the apparatus automatically will either go into replay or shut off, depending upon the position of selector switch 22 (FIG. 24). Assuming that selector switch 22 is closed, as the music roll 146 is about to leave the take up spool 151 (FIG. 19), arm 156 drops down from the dotted to the solid line position, thereby rotating cam 159 (FIG. 18) to actuate take up spool sensor switch 183 and move its poles 183a and 1831; down from the upper dotted line position to the lower solid line position, as shown in FIG. 24. As a consequence, current is supplied to the coil of delay relay 225, the circuit for which is completed to ground through the dotted line position of pole 236a. At the same time, ourrent flows through the closed selector switch 22 and the lock-in pole 236d in its lower dotted line position, temporarily maintaining current to reroll relay 236 and clutch solenoid 137. However, when the heater of thermal delay relay 225 is energized, it opens its pole 225p and opens the circuit to the start-stop relay 223 to shut off the entire apparatus. The delay function permits the music roll 146 to completely clear the take up spool 151 before the apparatus shuts off. At this point, it is to be noted that the energization of delay relay 225 is only temporary because as soon as its pole 225 is open, it de-energizes start stop relay 223 to open its pole 223p, and thereby cut off current fiow to the heater of the delay relay which immediately becomes de-energized and returns its pole 225p to the closing position, permitting restarting of the apparatus.

Assuming that the selector switch 22 is open, the apparatus automatically will go into continuous replay. Once again, at the end of the reroll function or operation, the take up spool sensor switch 183 drops to the solid line position of FIG. 24, cutting off the current to reroll relay 236 and solenoid of clutch 127. Immediately, the reroll relay 236 is de-energized to move its poles back to the solid line position, whereby the direction of motor rotation is reversed, and simultaneously, the de-energization of clutch 127 permits driving engagement between the dogs 108 and 126 (FIG. 23). Since selector switch 22 is open, no current can be supplied to reroll relay 236 and clutch 127 through branch 246, and even though the upper pole 183a of music roll sensor switch 183 closes the circuit to delay relay 235, this circuit is immediately broken by the movement of pole 236a from its lower dotted line position to its upper solid line position. Thus, delay relay 225 is prevented from actuating and shutting off the apparatus.

Assuming that a roll 146 has been played, the apparatus has been shut off and it is desired to remove roll spool 143 and replace it with another roll, the operator merely moves the music roll spool 143 to the left and removes the same. The apparatus will not automatically start, even though this movement momentarily closes sensor switch 196, because removal of the spool automatically opens sensor switch 192, breaking the circuit to start-stop relay 223.

Manual controls The various manual controls of the inventive apparatus also serve useful purposes. For example, a manual start switch 25 is connected between line 226 and the coil of start stop relay 223 (FIG. 24). Thus, should the operator inadvertently close the selector switch 22 to the shut off position instead of replay, he merely needs to close the normally open manual start switch 25 on control panel (FIG. 2) to restart the apparatus, this manual switch taking the place of the second music r-oll sensor switch 196 in FIG. 24. Alternatively, the operator could momentarily move the music roll spool 143 to the left far enough to momentarily close switch 196 in order to energize and lock in start stop relay 223.

Likewise, should it be desired to stop or shut off the apparatus at any time, the operator can manually open the normally closed manual stop switch 26 on control panel 20 (FIG. 2), thereby immediately de-energizing relay 223 (FIG. 24) and shutting off the apparatus;

Moreover, the user of the piano often encounters rolls which are somewhat damaged as by torn or frayed edges but which are otherwise playable. Also, special rolls sometimes are encountered which have special additional marginal perforations which were originally intended for special functions on a special player piano, but which are otherwise playable on a modern player piano. These damaged and special rolls will sometimes undesirably actuate unwanted functions. For example, a torn roll, or a roll with a special marginal perforation might energize an undesired note expression channel or brake solenoid 132 through reroll br-ush 2,10r. Accordingly, the prescut apparatus incorporates switch 23 to disconnect the marginal sensor brushes, such as expression brushes 210a and reroll brush 2101', so that these damaged and special rolls may be satisfactorily played. To this end, it is merely necessary for the operator to open the normally closed marginal cancel switch 23 (FIG. 24) to open the various marginal reading circuits. At the same time, the expression function may be manually controlled through variable resist-or 21.

It will now be seen how the invention accomplishes its various objects and the various advantages of the invention will likewise be apparent. While the invention has been described and illustrated herein by reference to certain preferred embodiments, it is to be understood that various changes and modifications may be made in the invention by those skilled in the art, without departing from the inventive concept, the scope of which is to be determined by the appended claims.

What is claimed is:

1. In apparatus for electrically actuating a musical instrument such as a piano and including an upper music roll spool and drive spindle freely rotatable in one direction, a lower take up spool and drive shaft for rotating said music roll spool and spindle in said one direction, and a music roll operatively connecting said spools, the combination therewith of a generally U-shaped carriage having a pair of arms journalled intermediate their outer and inner ends on said drive shaft at each end of said take up spool, a contact roller journalled in the outer ends of said arms and engageable with said music roll, sensor means arranged adjacent said take up spool, first means for automatically moving said contact roller downwardly and the portion of said music roll between said spools outwardly into a lower operative position in contact relationship with said sensor means, and second means for automatically moving said music roll portion inwardly and said contact roller upwardly to an upper inoperative posiiton between said spools.

2. The combination of claim 1 wherein:

the music roll has a female attaching member at one end thereof;

the take-up spool has an annular recess forming a reduced portion in its outer periphery; and

a plurality of elongated male attaching members are positioned to project outwardly from said reduced portion toward said outer periphery and are severally engageable in said female attaching member for facilitating attachment of the music roll to the takeup spool.

3. The combination of claim 1 wherein:

the music roll has a female attaching ring centered at one end thereof;

the take-up spool is rotatable in a given direction for winding the music roll thereon and has a central annular recess forming a reduced portion in its outer periphery; and

four elongated male attaching pins are embedded in and project outwardly from said reduced portion towards said outer periphery, said pins being inclined in said given direction and being severally engageable in said ring for facilitating attachment of the music roll to the take-up spool.

4. The combination of claim 1 wherein said first means includes outer and inner fixed pulleys on the outer and inner ends respectively of one of said carriage arms, an

upper drive pulley portion on said spindle, and a resilient endless belt riding in said pulleys. and pulley portion, whereby upon rotation of said music roll spool and drive spindle by said take up spool and drive shaft in said one direction, said music roll is driven downwardly toward said take up spool and said belt is driven by said spindle pulley portion downwardly through said outer pulley and upwardly through said inner pulley to pivot the outer ends of said carriage arms and said contact roller downwardly from said upper inoperative position to said lower operative position, said contact roller moving said music roll portion outwardly while so pivoting downwardly.

5. The combination of claim 1 wherein said second means includes a brake mechanism actuatable for fixing said music roll spool drive spindle against rotation in said one direction while said take up spool and drive shaft continue to rotate in said one direction and draw said music roll portion into a taut condition, whereby said music roll portion moves inwardly and pivots said contact roller and outer ends of said carriage arms upwardly from said lower operative position to said upper inoperative position.

-6. The combination of claim 5 wherein said first means includes outer and inner fixed pulleys on the outer and inner ends respectively of one of said carriage arms, an upper drive pulley portion on said spindle, and a resilient endless belt riding in said pulleys and pulley portion, whereby upon rotation of said music roll spool and drive spindle by said take up spool and drive shaft in said one direction, said music roll is driven downwardly toward said take up spool and said belt is driven by said spindle pulley portion downwardly through said outer pulley and upwardly through said inner pulley to pivot the outer ends of said carriage arms and said contact roller downwardly from said upper inoperative position to said lower operative position, said contact roller moving said music r-oll portion outwardly while so pivoting downwardly.

7. In apparatus for electrically actuating a musical instrument such as a piano and including an upper music roll spool and first drive shaft freely rotatable in the play direction, a lower take up spool and second drive shaft for rotating said music roll spool and first drive shaft in the play direction, the combination therewith of a music roll operatively connecting said spools and provided with a reroll perforation, a generally U-shaped carriage having a pair of arms journalled intermediate their outer and inner ends on said drive shaft at each end of said take up spool, a contact roller journalled in the outer ends of said arms and engageable with said music roll, sensor means arranged adjacent said take up spool and engageable with said contact roller through said perforation, first means for automatically moving said contact roller upwardly and the portion of said music roll between said spools inwardly from a lower operative position in contact relationship with said sensor means to an upper inoperative position away from said sensor means and between said spools, and second means for automatically rerolling said music roll on said music roll spool after said contact roller and music roll portion have been moved into said upper inoperative position.

8. The combination of claim 7 wherein said first means comprises a first circuit including a first power supply, a solenoid including a coil connected to said power supply and an armature movable upon energization of said coil for actuating a brake mechanism, and a normlly open reroll switch composed of said sensor means and contact roller and closeable by contact therebetween through said reroll perforation for energizing said solenoid, a brake mechanism composed of a ratchet fixed on said first shaft and a pawl actuatable by said armature into engagement with said ratchet for fixing said first drive shaft against rotation in the play direction while said second shaft continues to drive said take up spool in said play direction and to draw said music r-oll portion into a taut condition, whereby upon registry between said sensor means and said reroll perforations, said reroll switch is closed to energize said solenoid and actuate said brake mechanism, said music roll portion moving inwardly away from said sensor means toward said take up spool and pivoting the outer ends of said carriage and said contact roller upwardly from said lower operative position to said upper inoperative position.

9. The combination of claim 8 wherein said second means comprises a second circuit including a reversible motor, a second power supply connected across the input and output sides of said motor, a normally open carriage limit switch connected across the input and output sides of said motor and closeable by said contact roller carriage when in said upper inoperative position, an electromagnetic clutch including a coil connected between said limit switch and said output side, a' stationary dog member fixed on said second shaft and a reciprocal armature-dog member journalled on said second shaft for movement into and out of driving engagement with said stationary dog member when said coil is de-energized and energized respectively, a reroll relay including a coil connected between said limit switch and said output side and double throw double poles alternately connected to said motor so as to rotate said motor in the play direction when said coil is de-energized and to rotate said motor in the opposite reroll direction when said coil is energized, a mechanical one way overrunning clutch journalled on said first shaft, and a transmission connecting said motor with said mechanical clutch and said mechanical clutch with said reciprocal dog member, whereby when said contact roller and carriage are moved to said upper inoperative position, said carriage limit switch is closed to simultaneously energize the coils of said relay and electromagnetic clutch, reverse the direction of rotation of said motor and transmission from play to reroll, and disengage said dog members, said mechanical clutch engaging and driving said first shaft and music roll spool in said reroll direction while said disengaged dog members permit said second shaft and take up spool thereon to free wheel and be driven in said reroll direction by said music roll as it is unwound from said take up spool and rewound on said music roll spool.

10. In apparatus for electrically actuating a musical instrument such as a piano and including an upper music roll spool and first drive shaft freely rotatable in one direction, a lower take-up spool and second drive shaft for rotating said music roll spool and said first drive shaft in said one direction, and a music roll operatively connecting said spools comprising:

a carriage having first and second arms, said second drive shaft being journaled in said first arm adjacent to first end of said take-up spool and journaled in said second arm adjacent to second end of said take-up spool;

a contact roller journaled in said arms and engageable with said music roll;

sensor means mounted adjacent said take-up spool;

first means for automatically moving said contact roller towards said sensor means to place said contact roller in an operative position and to place a portion of said music roll located between said music roll spool and said take-up spool in contacting relationship with said sensor means;

second means for automatically moving said music roll out of contacting relationship with said sensor means and said contact roller to an inoperative position away from said sensor means;

a mechanical one way overrunning clutch journaled on said first drive shaft;

an electromagnetic clutch including a stationary dog member fixed on said second drive shaft;

a reciprocal dog member journaled on said second drive shaft for movement into and out of engagement with said stationary dog member when said electromagnetic clutch is actuated; and

a transmission connecting said mechanical clutch with said reciprocal dog member of said electromagnetic clutch,

whereby when said transmission is driven in a first direction and said electromagnetic clutch is actuated to engage said dog members, the second drive shaft is driven in the said first direction while said mechanical clutch overruns and permits the first drive shaft to free wheel, and when said transmission is driven in a second direction opposite to said first direction and said electromagnetic clutch is actuated to disengage said dog members, said mechanical clutch engages and drives the first drive shaft in said second direction while said disengaged dog members permit the second drive shaft to free wheel.

11. In apparttus for electrically actuating a musical instrument such as a piano the combination comprising:

an upper music roll spool, and a drive spindle and a dummy spindle for supporting said music roll spool, said music roll spool and said spindles being freely rotatable in one direction, said dummy spindle reciprocal between a first position when said music roll spool is being inserted and removed, a second position when said music roll spool has been removed and a third position intermediate said first and second positions when operatively supporting said music roll spool;

resilient means normally biasing said dummy spindle into said first position;

a lower take-up spool and drive shaft for rotating said music roll spool and said spindles in said one direction;

an electric motor driving said drive shaft;

circuit means operatively associated with said spindle means in said first and second positions for automatically starting and stopping said motor, respectively, and in said third position for automatically maintaining current to said motor;

a music roll operatively connecting said spools;

a generally U-shaped carriage having a pair of arms journaled intermediate their outer and inner ends on said drive shaft at each end of said take-up spool;

a contact roller journaled in the outer ends of said arms and engageable with said music roll;

sensor means arranged adjacent said take-up spool;

first means for automatically moving said contact roller downwardly and the portion of said music roll between said spools outwardly into a lower operative position in contact relationship with said sensor means; and

second means for automatically moving said music roll portion inwardly and said contact roller upwardly to an upper inoperative position between said spools.

12. The combination of claim 11 wherein:

said circuit means includes power supply means connected across the input and output sides of said motor;

first and second switch means connected in series in the input side and severally actuata'ble by said dummy spindle;

start-stop relay means including normally open, lock-in pole means connected to said input side in series with said first switch means and in parallel with said second switch means and between said second switch means and said motor; and

coil means connected across said input and output sides between said second switch means and said motor and through said pole means when closed and being energizable by closing of said second switch means for locking said pole means in closed position,

whereby upon insertion of said music roll spool said dummy spindle is momentarily moved from said first position wherein said first and second switch means are open to said second position wherein said first and second switch means are closed to energize said coil means and lock said pole means in closed position, upon completion of such insertion said resilient means biases said dummy spindle to said third position wherein said second switch means is opened but said first switch mean is maintained closed to complete said circuit means to said motor through said closed and locked pole means, and upon removal of said music roll spool said dummy spindle is moved to said second position momentarily, but said resilient means biases said dummy spindle to said first position thereby opening said first switch means to break said circuit means to said coil means.

13. In apparatus for electrically actuating a musical instrument such as a piano including an upper music roll spool and drive spindle freely rotatable in one direction, a lower take-up spool and drive shaft for rotating said music roll spool and spindle in said one direction, and a music roll operatively connecting said spools and provided with marginal openings capable of initiating various functions, the combination comprising:

circuit means for cancelling said functions and including power supply means;

a generally U-shaped carriage having a pair of arms journaled intermediate their outer and inner ends on said drive shaft at each end of said take-up spool;

a contact roller connected to said power supply means and journaled in the outer ends of said arms for engagement with one side of said music roll;

sensor brush means arranged adjacent said take-up spool and connected to said power supply means for engagement with the other side of said music roll and with said contact roller through said openings for initiating said functions;

first means for automatically moving said contact roller downwardly and the portion of said music roll between said spools outwardly into a lower operative position in contact relationship with said sensor means;

sec-ond means for automatically moving said music roll portion inwardly and said contact roller upwardly to an upper inoperative position between said spools; and

normally closed marginal cancel switch means connected to said power supply means whereby upon opening of said switch means said circuit means is broken and said functions are cancelled.

14. In apparatus for electrically actuating a musical instrument such as a piano and including an upper music roll spool and drive spindle freely rotatable in one direction, a lower take-up spool and drive shaft for rotating said music roll spool and spindle in said one direction, a music roll operatively connecting said spools, a generally U-shaped carriage having a pair of arms journaled intermediate their outer -and inner ends on said drive shaft at each end of said take-up spool, a contact roller journaled in the outer ends of said arms and engageable with said music roll, sensor means arranged adjacent said take-up spool, first means for automatically moving said contact roller downwardly and the portion of said music roll between said spools outwardly into a lower operative position in contact relationship with said sensor means, second means for automatically moving said music roll portion inwardly and said contact roller upwardly to an upper inoperative position between said spools, and an electric motor for driving said music roll spool in one direction during the reroll cycle, the combination comprising:

circuit means for automatically shutting said motor otf at the end of said reroll cycle, said circuit mean including power supply means connected across the input and output sides of said motor;

a double throw take-up spool sensor switch pole movable between a first position in response to the presence of said music roll on a portion of said takeup spool during said reroll cycle and a second position in response to the absence of said music roll from said take-up spool portion as said music roll is about to leave said take-up spool near the end of said reroll cycle, said sensor switch pole being connected across said input and output sides in both positions during said reroll cycle;

a reroll relay including a coil connected between said sensor switch pole in said first position and said output side during said reroll cycle, and including first and second poles movable between shut off and reroll positions upon de-energizati on and energization respectively of said coil, said first pole being connected to open circuit in said shut off position and between said sensor switch pole and said output side in said 23 reroll position, and said second pole being connected to open circuit in said shut oif position and between said input side and said coil in said reroll position;

a start-stop relay including a normally open lock-in pole connected to said input side and a coil energizable for closing and locking its pole in closed position and connected across said input and output sides through said lock-in pole when closed; and

a delay relay including a normally closed pole connected in series with said start-stop relay coil and energizable means for opening said normally closed pole and connected between said sensor switch pole in said second position and said reroll relay first pole in said reroll position,

whereby when said sensor switch pole moves to said second position, said energizable means of said delay relay is energized to open said normally closed pole, die-energizing said coil of said start-stop relay to open its pole and shut off said motor after said music roll leaves said take-up spool, whereupon said energizable means of said delay relay is de-energized to close its pole and enable re-energization of said start-stop relay coil for restarting said motor, even though said sensor switch pole remains in said second position.

15. In apparatus for electrically actuating a musical instrument such as a piano and including an upper music roll spool and drive spindle freely rotatable in one direction, a lower take-up spool and drive shaft for rotating said music roll spool and spindle in said one direction, a music roll operatively connecting said spools, a generally U-shaped carriage having a pair of arms journaled intermediate their outer and inner ends on said drive shaft at each of said take-up spool, a contact roller journaled in the outer ends of said arms and engageable with said music roll, sensor means arranged adjacent said take-up spool, first means for automatically moving said contact roller downwardly and the portion of said music roll between said spools outwardly into a lower operative position in contact relationship with said sensor means, second means for automatically moving said music roll portion inwardly and said contact roller upwardly to an upper inoperative position between said spools, and an electric motor for driving said take up spool in one direction during the play cycle and for driving said music roll spool in the opposite direction during the reroll cycle, the combination comprising:

cricuit means for automatically reversing said motor for replay at the end of said reroll cycle, said circuit means including power supply means connected across the input and output sides of said motor;

a double throw take up spool sensor switch pole movable between a first position in response to the presence of said music roll on a portion of said take up spool during said play and reroll cycles and a second position in response to the absence of said music roll from said take up spool portion as said music roll is about to leave said take up spool near the end of said reroll cycle, said sensor switch pole being connected across said input and output sides in said first position during said reroll cycle and to open circuit in said second position;

a reroll relay including a coil connected between said sensor switch pole in said first position and said output side during said reroll cycle, and including first, and second poles movable between play and reroll positions upon de-energization and energization respectively of said coil, said relay first and second poles being connected to said motor in said play and reroll positions for driving said motor in said play and reroll directions respectively,

whereby when said sensor switch pole moves to said second position, said reroll relay coil is immediately deenergized to move its poles to said play position and reverse said motor for replay.

16. In apparatus for electrically actuating a musical instrument such as a piano and including an upper music roll spool and drive spindle freely rotatable in one direction, a lower take-up spool and drive shaft for rotating said music roll spool and spindle in said one direction, a music roll operatively connecting said spools, a generally U-shaped carriage having a pair of arms journaled intermediate their outer and inner ends on said drive shaft at each end of said take-up spool, a contact roller journaled in the outer ends of said arms and engageable with said music roll, sensor means arranged adjacent said take-up spool, first means for automatically moving said contact roller downwardly and the portion of said music roll between said spools outwardly into a lower operative position in contact relationship with said sensor means, second means for automatically moving said music roll portion inwardly and said contact roller upwardly to an upper inoperative position between said spools, and a reversible electric motor for driving said take-up spool in one direction during the play cycle and for driving the music roll spool in the opposite direction during the reroll cycle, the combination comprising:

circuit means for automatically shutting said motor ofi at the end of the reroll cycle or reversing said motor for replay at the end of said reroll cycle, said circuit means including power supply means connected across the input and output sides of said motor;

a take-up spool sensor switch including first and second double throw poles movable between a first position in response to the presence of said music roll on a portion of said take-up spool during said play and reroll cycles and a second position in response to the absence of said music roll from said take-up spool portion as said music roll is about to leave said takeup spool near the end of said reroll cycle, said first pole being connected across said input and output sides in both positions during said reroll cycle and said second pole being connected across said input and output sides in said first position and to open circuit in said second position during said reroll cycle;

a reroll relay including a coil connected between both of said first and second poles in said first position and said output side during said reroll cycle, and including first, second, third and fourth poles movable between play and reroll positions upon de-energization and energization respectively of said coil,

' said relay first and second poles being connected to said motor in said play and reroll positions for driving said motor in said play and reroll directions respectively, said relay third pole being connected to open circuit in said play position and between said switch first pole and said output side in said reroll position, and said relay fourth pole being connected to open circuit in said play position and between said switch second pole and said coil in said reroll position; v

a start-stop relay including a normally open lock in pole connected to said input side and a coil energizable for closing and locking its pole in closed position and connected across said input and output sides through said lock-in pole when closed;

a delay relay including a normally closed pole connected in series with said start-stop relay coil and energizable means for opening said normally closed pole and connected between said sensor switch first pole in said second position and said relay third pole in said reroll position; and

a selector switch connected in parallel with said switch second pole,

whereby when said selector switch is closed and said sensor switch first and second poles move to said second position, said energizable means of said delay relay is energized to open its pole, de-energize said start-stop relay coil to open its pole and shut ofi said motor after said music roll leaves said take-up spool, whereupon said energizable means of said delay relay is de-energized to close its pole and enable re-energization of said start-stop relay coil for

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