US2831570A - Wire coiling machine having cams for holding the feed rolls separated - Google Patents

Description

April 22, 1958 w. CONRAD 7 WIRE COILING MACHINE HAVING CAMS FOR HOLDING THE FEED ROLLS SEPARATED Filed Aug. 2, 1954 4 Sheets-Sheet l INVENTOR. LUiLbuQr Cour-ad TTORNEY.

Aprll 22, 1958 w. CONRAD 2,801,570

WIRE comma MACHINE HAVING CAMS FOR HOLDING THE FEED ROLLS SEPARATED Filed Aug. 2, 1954 4 Sheets-Sheet 2 Ig'gcf.

P\ I a v m m m m 3 INVENTOR. UJ'ilbur' Conrad TORNEY Apnl 22, 1958 w. CONRAD 2,831,570

WIRE COILING MACHINE HAVING CAMS FOR HOLDING THE FEED ROLLS SEPARATED Filed Aug. 2, 1954 4 Sheets-Sheet 5 u-lm lll-llllll mgmr IINVENTOR. LUI Uou r" Co 11 ra d w. CONRAD 2,831,570

OR HOLDING April 22, 1958 WIRE COILING MACHINE HAVING CAMS F THE FEED ROLLS SEPARATED 4 Sheets-Sheet 4 Filed Aug. 2, 1954 I INVENTOR. wilbLU" Conrad ATTORNEY United States Patent WIRE COILING MACHINE HAVING CAMS FOR HOLDING THE FEED ROLLS SEPARATED Wilbur Conrad, Unionville, Hartley, Inc, Worcester, sachusetts Application August 2, 1954, Serial No. 447,278 9 Claims. (Cl. 203-142) Conn, assignor to Sleeper & Mass, a corporation of Massity for returning the gear segment to its starting position at the same speed as its forward motion. In the machine of the patents to Sleeper #1,452,l28 and Blount #2,096,065 the wire feeding rolls are driven through a clutch which is controlled by a cam mechanism arranged to stop the feed periodically for the wire cutting operation. The accuracy of feed in this type of machine is limited to the accuracy of the clutch and its operating mechanism. That is, the clutch, if improperly adjusted, may slip an uneven amount in successive cycles, causing difierent lengths of wire to be fed, thus causing faulty springs and rejections. In the Blount machine, a cam operates a clutch to stop the wire feed intermittently, but this construction requires a selective change speed mechanism to rotate the cam at a variable speed to change the length of the wire feed.

There is another type of spring coiling machine, familiarly known in the spring coiling trade as the pop-corn type, having constantly driven feed rolls, and these rolls are provided with cutaway portions or sections, one roll being keyed to the shaft and the other roll readily adjustable, so that they grip or feed the wire only through a predetermined portion of their 360 circumference. The length of wire that can be fed forward is limited to the circumference of the feed rolls, minus a 60 cutaway section of the rolls and minus any additional adjustment necessary to reduce the feed to the spring makers requirements. Such a machine is limited to making a coil of a length determined by the length of the peripheral groove on the feed rolls, and it must produce a coil within that one revolution of the feed rolls.

The primary object of this invention is to overcome the disadvantages in such prior types of wire coiling machine and to provide a universal machine which may coil various sizes of any predetermined length between a minimum and a maximum without the loss of time, consequent in the segment type coiler and of greater feed capacity; also which is faster and more accurate in feed than the clutch type coiler, and which overcomes the very limited feed length of the popcorn type coiler.

In accordance with this invention, I eliminate the intermittently driven gear segments and clutches and provide a cam control mechanism which permits the wire feeding rolls to feed wire through a widely varied but predetermined number of revolutions of the feed rolls and then relatively separates the rolls to release their feeding grip on the wire and give time for severing the wire.

A further object of the invention is to provide a ma 2 chine of this type which may be readily adjusted as to the number of full turns of the feed rolls to provide an accurate and widely varied length of wire for coiling purposes. Another object is to provide a wire coiling machine in which the wire cutting operation is effected once per revolution of 'a slowly rotated controlling cam, while the wire feed is produced by continuously driven feed rolls synchronized with the cam.

Another object is to provide a machine of this type in which the wire feed may be varied by adjusting the speed of the feed rolls and yet providing a relatively slow movement of the pitch, diameter, and cutter cams so that for any speed of wire feeding there is close control of the spring produced and ample time for severing the wire after the feed is completed.

In prior art machines such as illustrated in the patents to Sleeper #1,266,070 and Halvorsen #2,455,863, the position of a coiling point relative to an arbor about which the wire is coiled determines the diameter of the coil, and this is varied by adjusting the length of a cam operated rod connected through a turnbuckle or threaded member to the coiling point. A related cam and adjustable rod construction governs the pitch of the coil. In

the standard construction, when the locknut which holds the turnbuckle of the adjustable rod from turning is tightened, it displaces or changes the relative position of the screw threads in the turnbuckle with a consequent slight variation in the effective length of the rod and a consequent incorrect variation in the diameter or pitch. Only by a series of adjustments can this inaccuracy be corrected. 7

A further object of the invention is to provide a construction whereby this adjustment of the rod length may be readily and accurately effected to provide a'correct control of the coil size, pitch and shape. will be apparent in the following disclosure.

In the prior machines of this general class, the wire feed is limited to one revolution of the feed rolls and the camshaft, which controls the pitch and diameter of the coil as well as severing it from the wire, is geared to these rolls with a l to 1 ratio. In order to feed a variable but predetermined length of wire, I provide a variable speed mechanism, which allows the wire feeding rolls to rotate a greater and predetermined number of revolutions relative to that of the camshaft and thus feed more wire for a given cycle of the camshaft. It is, however, necessary that the feed rolls be made inoperative for a sufiicient time for the wire cutting step, irrespective of their rotative speed. To this end, I separate the driving rolls, such as by raising the upper roll, which stops the wire feed for a predetermined interval, and this is preferably accomplished by a cam system coordinated with the cam. controlled wire cutting mechanism which insures ample time for cutting speed. Also, the mechanism which separates the rolls must provide for an accurate starting and stopping of the wire feeding, irrespective of the driving speed of the feed rolls. I have, therefore, provided two relatively adjustable lifting cams associated with relatively separable feed rolls, whose primary function is to separate the feed rolls from driving engagement with the wire and subsequently to restore the driving contact, and thus to provide for an accurate starting and stopping of the wire feed. A control cam governs the operation of the lifting cams. association With these two lifting cams, there is a holding cam which serves to maintain the feed rolls separated for a variable but controlled length of time after the wire feeding and during the wire cutting period and between the operation of the two lifting cams. That is, one lifting cam serves to separate the feed rolls after an accurate feeding of a given length of wire, and the holding cam comes into play to hold the feed. .rolls'separated during 4 Other objects the wire irrespective of the feed rollthe wire cutting step, and thereafter the second of the lifting cams is rendered operative by the control cam for starting the wire feeding at a predetermined point, after the holding cam has finished its function, and thus lowering the feed roll accurately into wire feeding engagement.

Referring to the drawings illustrating one embodiment of the invention:

Fig. 1 is a fragmentary, diagrammatic, perspective view of essential portions of the mechanism involving the lifting and holding cams which serve for the intcrr. on of the pitch and diameter control cams being eliminated for clarity;

Fig. 2 is a fragmentary elevation of the same parts of the machine, but showing the pitch and diameter control cams in position on the camshaft;

Fig. 3 is a fragmentary front elevation of the machine showing the wire coiling parts, control cam parts and part of the change speed gear system;

Fig. 4 is a development of the barrel shaped control cam which shifts the follower of the lifting cams;

Fig. 5 is a fragmentary elevation of the cam mechanisms for controlling both the wire cutting operation and the new adjustment means for controlling the diameter of the wire coil; and

Fig. 6 is a detail taken on the line 66 of Fig. 5, showing the manner of splitting the clamping nut of the adjustment means.

In accordance with this invention, the two grooved wire feeding rolls 1 and 2 are respectively mounted on the ends of and continuously driven by shafts 3 and 4 which have intermeshing gears 5 and 6 arranged to insure their positive and synchronous rotation. The wire 7 (Fig. 3), as fully described in said patents, is fed forward between two pairs of grooved wire guides 8 and 9 located on opposite sides of the feed rolls to the coiling zone. The coiling tools include a reversible grooved wire guide 10 on the toolholder and a movable grooved coiling point 11 which force the wire to form into a coil around an arbor in the toolholder, as is understood. The diameter of the coil is controlled by moving the coiling point 11 towards or from the arbor by mechanism comprising the crank arm 12 which is operated from a cam shaft in the machine. The pitch or spacing of the coils is determined by a pitch tool 13 which engages the wire behind the first coil and causes the adjacent coils to be spaced in accordance with the laterally adjustable position of that tool. After a suitable length of wire has been coiled, one of the cutters 14 is brought into engage ment with the wire and severs it against the cutting edge of the arbor. Either one of the cutters may be used, depending upon whether the wire is coiled downwardly or upwardly, as is determined by a suitable interchange of the parts in the coiling zone. These cutters 14 are mounted on rock shafts 16 and suitably connected with a rocking lever shown in Figs. 1 and 5 for a cam controlled operation. The wire is fed forward from a suitable supply to the coiling point and arbor by frictional engagement between the two grooved feeding rolls 1 and 2. These rolls may be provided with several grooves of different sizes so as to accommodate wires of different gauges, and the various coiling points and other mechanisms are mounted for adjustment in accordance with standard practice, so that they will be in alignment with the wire feeding groove selected.

In accordance with my invention, the feed rolls 1 and 2 are driven continuously but at desired uniform speeds, and the wire 7 is fed forward only when the feed rolls are in frictional driving engagement therewith. An accurate feeding of a desired length of the wire may be accom plished by radially lifting a feed roll, as by tilting the upper drive roll shaft 3 to lift its associated feed roll 1. To this end, the upper shaft is mounted in a rocking bearing (Fig. 2) which provides for a slight tilting of the shaft and an upward movement of the feed roll 1 so as wire feed and the cam control for the wire cutt to separate that roll from frictional driving engagement with the wire 7 carried between the two rolls. This hearing may comprise a ball raceway 17 suitably mounted on the reduced end of the shaft 1 and having the balls riding in a concave bearing block 18 shaped for the tilting movement and which is mounted on the machine frame. The ball bearings are held in place against a shoulder on the shaft by means of a locking nut 19. Various other suitable constructions may be employed.

order to lift the upper drive roll from frictional driving engagement with the wire and to return it accurarely, the upper feed roll shaft 3 carries at its outer end two angularly adjustable lifting cams 20 and 21, which have parts of their surfaces concentric with the feed roll l and merging with high portions which serve for a controlled lifting and lowering of the upper feed roll. The inner or right hand cam 21 is mounted adjacent to the upper feed roll 1 and is separated from the outer left hand cam 20 by a spacer 22 which provides a neutral zone. A removable clamping block 23 at the outside is held in position by means of suitable cap screws which may be loosened for an angular or rotativc adjustment of the high spot of either of the two earns 25} and 21 so as to change their relative angular positions. These two cams are clamped and rotated positively with the upper feed roll.

Associated with these lifting cams is a cam follower ring 25 mounted to rotate with and concentric to the lower feed roll 2 and its shaft 4. This ring is suitably mounted on the shaft and may be fixed to and positioned by a cylindrical follower block 26 which slidably floats on the shaft 4. The follower block 26 is arranged to be moved axially of that shaft by means of a yoke 27 which has its forks arranged to interlit with and ride in a groove 28 on the block 26. The yoke 27 (Fig. 2) is fixed to an inner cylindrical spring barrel 29 and an outer cam follower sleeve 36 which are slidable on an intermediate hollow sleeve 31 therebetween which is fixed on a standard of the machine frame 32. A spring 34 is mounted in the barrel 29 between a closure 36 threaded in sleeve 31. and a removable screw plug 35 at the outer left hand end of the barrel 2? which is rigid with the yoke 27 and outer sleeve 39. The spring is held under compression and urges the follower ring 25 towards the left and into engagement with the left hand lifting cam 29.

The movement of the block 26 and its follower ring 25 is determined by a specially shaped control cam 38, 39 which is keyed to the operating camshaft 4b suitably mounted in the lower part of the machine and arranged to rotate in timed relation with the various earns thereon which control the diameter and pitch of the spring and the cutting operation. This control cam is made of two relatively adjustable, concentric, barrel shaped sections 38 and 39 which provide a side cam face so shaped and arranged, as shown in the diagrammatic development thereof in Fig. 4, as to govern the position of a cam follower roller 42 carried in a yoke arm 43 that serves as an extension of the cam fork 27, as shown in Fig. 2 and diagrammatically in Pig. 1 but with the omission of the spring and associated elements which control the position of the yoke 27. Thus, a constant rotation of the control cam controls the position of the cam roller 42 and through it the position of the yoke 27 and the cam follower-ring 25.

The inner ring 38 of the control earn, as shown in the development plan of Fig. 4, provides a highest spot 44 of such length and height as to hold the follower ring 25 at the right for engagement with the lifting cam 21 of the upper feed rc-ll shaft. This particular cam section 44 determines the time of stopping the wire feed prior to the wire cutting operation, by causing the lifting'carn 21 to lift the upper feed roll from contact with the wire after a predetermined length of wire has been fed to the coiling Zone. The two parts of the control cam provide an intermediate lower level portion 45 and.

the outer ring 3 has a depression 46, which lie in planes at right angles to the shaft axle. The ring 38 is cut away, as shown, along the dotted line 48, so that this cam ring has only the high spot 44, and the cut away part 48 provides for adjusting the position of part 44 relative to the depression 46 in the outer cam ring 39. The outer ring has only the depression 46 and the level portion 47. When the cam roller 42 engages the level 45, the fork 27 will be shifted half way toward the left and the cam follower ring 25 will lie in the neutral zone between and out of contact with the two cams and 21. This follower position would allow the upper feed roll 1 to drop into full and driving engagement with the wire, unless otherwise prevented, as will be explained. When the follower roll 42 engages the lowest fiat portion 46 of the cam 39, the follower ring 25 will be shifted into contact with the outer or left hand cam 24) on the upper drive shaft, and this causes the lifting cam 20 to lower the upper drive roll 1 into driving engagement with the wire as the ring 25 travels down the face of the high part of cam 20. The level portion 47 of the cams provides a neutral position in line with the surface 45 for holding the ring 25 between the cam rings 28 and 21. During this major portion of the time provided by cam surface 47, the upper feed roll is not being raised from the wire, and it is therefore held down under spring pressure to drive the wire forward for a coiling operation. The cam surface may be so shaped that the neutral position for the cam ring 25 is at the left of cam 20 instead of between the earns 20 and 21. The two cam parts 38, 39 are angularly adjustable so as to change the timing of the cam follower 25, so that the latter may be moved only when the low part of cam 28 or 21 is opposite thereto, since the high part would interfere with the follower movement. Thus the effective cam control shape may be changed, as desired to control the time at which the ring 25 will be under either of the cams 20 or 21 or located therebetween in a neutral position. The earns 20 and 21 are likewise angularly adjustable on their shaft and may each be made of two relatively adjustable plates for varying their effective high and low portions.

The cams 20 and 21 on the upper feed roll shaft are primarily for the purpose of accurately controlling the starting and stopping of the wire feed or the coiled wire length. That is, as the high portion of the right hand or inner cam 21 comes into engagement with the follower ring 25, its sloping or leading edge lifts the upper roll rapidly and accurately and retains it lifted while the partial cylindrical high portion of the cam rides on the follower ring 25. This, however, does not give time enough for the wire cutting operation throughout the complete range of wire feeds. Hence, I have provided a holding cam 50 for this purpose. This is a cam disk mounted on the camshaft 40 which has a high spot on its periphery arranged to engage a cam follower roller 52 (Figs. 1 and 2) pivotally mounted on a pin on the side of a vertically movable slide 53 suitably mounted on the machine frame. This slide is arranged to hold up the feed roll shaft housing 55 which carries roller bearings (not shown) for supporting the upper feed roll shaft 3. That housing is pressed downwardly by a spring 56 (Fig. 2) under compression which is mounted between the top portion of the housing and a movable pressure plate 57. An adjustable screw 58 threaded in a cross piece of the framework 32 serves to push'down on the pressure plate 57 and thus adjusts the force with which the upper feed roll 1 is held against the wire. The slide 53 engages two pins 60 slidably mounted in vertical holes in the housing 55. These pins are adjustably positioned by means of parts 62 threaded in the housing and held by lock nuts. The pins 60 project downwardly below the housing to an adjustable extent and thus vary the uppermost position of the rolls effected by the holding cam 50' audits associated slide 53. This slide in the form shown has a large opening 64 therein surrounding the lower roll shaft 4 and providing for movement of the slide without interference.

The function of the holding cam 50 is to hold the upper feed roll I lifted out of engagement with the wire on the lower feed roll during the period while the cam follower ring 25 is to be shifted from the inner' vcam 38, 39 and its rotative speed issuch as to give ample time for the wire feeding, forming, and cutting operation. An adjustment of this timing may be had by providing a second holding cam member 66 engaging the follower 52 which may be adjusted angularly relative to the first holding cam 58. The high portions of these two holding cams are in a cylindrical surface, and by varying angularly the positions of the two cams that cylindrical portion may be lengthened or shortened as needed in accordance with the desired machine adjustments.

The holding cam is timed in its relationship to hold the upper feed roll away from the wire while the cam roller 42 is moved from the high spot 44 of the barrel cam 38 past the neutral position 45 and onto the lower level 46. The cam follower ring 25 has a high rib 68 at its right hand side which, for the position of the cam ring 25 shown in Fig. 2, lies against the right hand side of the cam 21 and thus aids in holding the cam follower ring 25 in place against the pressure of the spring 34 while the high portion of the cam 21 is lifting the feed roll. After the feed roll has been lifted, the holding cam 5t) comes into play to hold the housing and upper feed roll 1 in the lifted position. This permits the rib 68 to clear the cam 21 and the follower ring 25 to be slid toward the left by the operation of the spring 34 when permitted by the barrel cam 38. The high portion of the lifting cam 21 is short andthe cam quickly loses contact with the ring'25, so that the ring may pass across the neutral position between the two earns 20 and 21 and opposite to the left handcam 20 while the holding cam 50 is effective to hold the feed rolls separated, so that the cam may thereafter lower the upper wire feeding -roll accurately and in a proper timed relationship. During this period of movement of the cam follower 25 from right to left, while the lifting cam 21, the holding cam 50. and the lowering cam 20, maintain the feed roll 1 outof engagement with the wire,

the wire cutting operation takes place. After the lowering cam 20. effects engagementof the feed rolls 1 and 2 with the wire and starts the wire feed, cam roller 42 rides up on the long level 47 and the cam ring 25 is again shifted to theneutral intermediate position between earns 20 and 21. .This neutral position prevents any further interruptionof the wire feed by earns 21 and 20. Just before the next lifting step, the high portion 440i the control cam shifts the ring 25 to its right hand position as ispermitted by the spacing between the ring and the cam 21. That is, the ring 25 does not touch the low part of either cam 20 or 21 and can move readily when opposite the same. When the wire feed is to be stopped and cutting to proceed, the high part of the lifting cam 21 rides up onto the ring 25 and the cycleof operation is repeated. In this machine, one wire spring is made for each rotation of the camshaft 40.

The barrel cam 38 is adjustably mounted on the side of a plate 70 by means of set screws 71 (Fig. 1) adjustably positioned in elongated slots 72 in the plate. A hub 74 of that plate (Fig. 2) is keyed to the shaft 40 and the parts are held together by a suitable nut on the end of the shaft. This provides for a rotative relative timing adjustment of the barrel cam relative to the camshaft 40. Similarly, the outer control cam part 39 is separately and adjustably mounted on plate 70 by set screws 75 in slots 76.

The length of wire that is to be fed to the driving rolls is adjusted by means of a suitable change speed mechanism, such as the interchangeable gear system illustrated. Power is suitably applied to the feed rolls through a driving gear 80 (Fig. 2) freely mounted on the camshaft 4t! and meshing with feed roll gear 6 and thus driving gear and both feed rolls. The lower shaft 4 serves through a change gear mechanism to drive the camshaft 40 at a required speed. The camshaft has a large gear 85 keyed thereto and meshing with a small gear 86 on a jack shaft carrying a large gear 87 meshing with a small gear 88 on the feed roll shaft 4. A swinging bracket 89 (Figs. 2 and 3) has an arm 90 pivotally mounted to swing about the axis of the camshaft 40. The gear 87 has its shaft adjustably mounted in an elongated slot 91 radial of the shaft 41 in the bracket. Another slot 92 in the bracket is concentric with the shaft 40 and a clamp screw 93 therein serves to fix the bracket in an adjusted position on the machine frame. Thus by a suitable selection of gears and adjustment of their bracket support the change speed system may give any preselected relative speed ratio for the camshaft and the feed rolls, depending on the gears selected and the rotative speed imparted by a suitable driver to the gear 89. The gears and speed ratios are preferably selected within limits to vary the speed of the camshaft with the feed rolls operating at a uniform speed. Various constructional details may be employed as desired to provide the change speed system and to mount the gears on the machine for ready removal from the outer end of the frame. Also, the power may be otherwise applied to rotate the feed rolls 1 and 2 at a constant or uniform speed for all desired speeds of the camshaft. Thus a ratio of rotation of the wire feeding rolls to the camshaft rotation may =be varied from 1:1 to 14:1 or more with an associated wire feed varying from near zero to over six feet by a suitable selection of the gears in the system illustrated and preferably to provide an overlapping wire feed range for the gears of two adjacent combinations of the sequence. The wire cutting or feed roll holding time is adjusted by varying the length of the high portion of the two parts of the holding cam 50, 66 and, if desired, by substituting lifting earns 20, 21 of longer high portions for the shorter feeds of feed roll rotation. A suitable angular length of the high portion of the holding cam 50, 66 is normally 60, and the total angular holding time of the combined holding and lifting cam motions may vary from 60 to 360 of the camshaft rotation. By spreading the holding cams to lengthen their high portion, the feeding time is decreased. The control cam 38 is coordinated with the other cams, as llll be understood. It will therefore be seen that if the lifting cams 20 and 21 were rotated at a high speed, and without the aid of the holding cam 50, there would not be sufficient time for cutting the wire. Hence, the holding cam is important for the longer feed ratios and gives about the same length of time for the cutting operation,

irrespective of the wire feed. However, it is possible to.

vary the non-feeding time by varying the angular relation of the cams 5i and 66 so as to lengthen or shorten the effective high point of'these two cam surfaces.

The various wire coiling operations may be effected and controlled in accordance with standard practice as set forth in the patents listed above. It, however, may be stated for clarity of description that the rock shaft 16 which controls the movement of the cutter 14 (Fig. 3) may be rocked by means of a cam 100 (Fig. 5) on the shaft 4% which has a steeply approached high point 101 arranged to thrust against a roller 102 on a rocking lever 103 suitably pivoted at 104 on the machine frame and draw downwardly on a pull bar 105 of adjustable length,

as provided by suitable turnbuckle construction. As shown, the threaded rod 106 maybe threaded into or out of the two connecting parts of the member to shorten or lengthen its effective throw. The upper end of the lever 105 is connected to a short rock arm 107 which is suitably secured to the shaft 16 and thus serves to rock that shaft and move whichever of the cutting tools 14 is effective at the time. Thus, as will be appreciated, the operation of the cutter is dependent solely on the rate of revolution of the camshaft 4i), and as above stated, the holding cam 5'6 may be adjusted to give adequate time for a non-feeding step which is independent of the rate of rotation of the feed rolls.

The diameter of the coil is controlled by the position ceiling point 11 relative to the center of the coil 15 being formed. Under certain circumstances, it is (1 ed to make a cone shaped or tapered coil spring, for example, which has it gradually increasing diameter, and for that purpose the coiling point 11 may be moved outwardly or inwardly by means of the rock arm 12 which is suitably connected to the support 110 (Fig. 3) carrying the coiling point. The rock arm 12 is suitably mounted on a rock shaft 131! (Fig. 5) and the latter is rocked by means of a short lever arm 131 pivoted to a connecting rod 132 which is operated by a cam 133 mounted on the camshaft 44 That cam thrusts against a cam roller 134 carried on an arm 135 pivotally mounted on the rocking support 1 94. Beneath that rocking arm 135 is an arm 136 suitably pivoted at 137 and pivotally connected to the rod 132. The swinging arm 136 carries an adjustably positioned block 138, the upper rounded surface of which engages the rock arm 135 at some point, depending upon its adjustment, and thus providing an adjustable throw for the rod 132. This block 138 is threaded on an adjustment rod 139 which is mounted for rotation in a block 140 carried on the pivot mount of the arm 136. The screw threaded rod 139 has a head 141 by which that rod may be turned and the block 138 may be moved to various positions, such as the one shown in dotted outline in Fig. 5, and in that way change the effective length of throw of the rod 132 and so vary the amount of motion of the diameter controlling coiling point through the lever arm 131 and rock arm 12.

It has been found that there must be an accurate connection between the rock arm 12 and the swinging arm 136 for positioning the coiling point. In the construction illustrated, the lever 131 is urged towards an uppermost position by a tension spring 149 connected between the lever and a part of the framework. The outer end of the lever carries a pin 141 suitably mounted, as in a yoke on the end of arm 131, which rides in an elongated slot 142 in a connecting rod block 143 threaded on the rod 132. The clfective length of the connecting rod 132, 143 is accurately varied by means of a pointed screw threaded adjustment rod or pointed screw 145 threaded in the upper end of the slotted block 143 and resting in a coned hole in the top of the pin 141. As shown in Figs. 5 and 6, the upper end of the block 143 is a split and tapered jaw M6 threaded internally for screw 145. This tapered jaw is threaded externally into an interfitting tapered sleeve 147 having an internal tapered thread adapted to screw onto the split part 146 and compress the jaw and clamp or bind it tightly against the adjustment screw or threaded rod 145. This provides a tight fit for the screw threaded rod 145, so that it may be turned only with difliculty by the head 148. This takes up all play in the threaded parts 145, 146 and insures that for any adjusted positionof the screw 145, the latter engages the pin 141 radially and without lateral distortion of the adjustment made to position the arm 131. The screw 145 therefore locates the uppermost position of pin 141 relative to the block 143 against the pressure of a tension spring 149 connected to lever 131 and thus adjusts the position of the diameter controlling shaft 130 by a center thread clamping device providing an accurate locking adjustment of the length of parts 132143 and 145. This construction applies also to the pitch control cam 150 and its connection for the pitch adjustment, as will be evident by an inspection of Figs. 9 and 10 of the patent to Sleeper #1266070. This pitch control cam and connecting rod structure is a duplicate of the diameter control features except for necessary variations in cam shape and associated parts and so has not been specifically illustrated.

The operation of the device will now be apparent. The change speed gears are selected to permit the feed rolls to rotate through sufficient turns or angular distance to feed the wire continuously and provide the right length for the coil. The cams 2t) and 21 or their two parts are adjusted to locate their high portions properly for stopping and starting the wire feed. The control cams 38 and 39 in the adjusted positions of Fig. 3 provide the maximum wire feed for the gears selected, and by adjusting them angularly the feed may be reduced. Also, the control cam is adjusted to insure that the cam follower 25 moves laterally beneath cam 21 only when the lower surface portion of the lifting cam is opposite the roller, to prevent interference. With the control cam follower on the long flat portion 47 of its cam, the follower 25 is located between its earns 26 and 21 and the wire feed goes on until the high portion 44 of cams 38., 39 move its follower 42 and thrusts the ring 25 beneath the right hand cam 21. This causes an exactly timed lifting of the upper feed roll and stoppage of the wire feed. The short high portion of cam 21 quickly leaves contact with ring 25 and the latter is moved by spring 34 to a central position between the cams 2t) and 21, as is permitted by roller 42 riding down from the high 44 to the intermediate level 45 of the control cam 38. In the meantime, the high of cam 56 has moved to hold the upper feed roll away from the wire. During this non-feeding period, the cutter cam operates to cut the wire. Thereafter, the lower level 46 of control cam 39 comes into position and the spring 34 is permitted to thrust the ring 25 beneath the cam 29. Then the high part of cam 50 retreats to permit cam 20 to hold up the upper feed roll momentarily and lower it accurately onto the wire to start another feeding and coiling stage, while the low part 46 of cam 39 is efiective. The high part of cam 20 now leaves contact with ring 25 and the ring 25 is moved to its neutral position between cams 20 and 21 as the roller 42 climbs onto the long level portions 47 of the two control cams 38, 39. The cycle of operations again repeats.

Sufiicient time is provided for the cutting step by suitably adjusting the total length of the high parts of cam 50, 66 and there need be but little loss of time, although for the longer lengths of wire feed the camshaft is rotated quite slowly as compared with the feed roll speed. For the shorter wire lengths, the total length of the highs of the lifting cams gives a basic 60 angle sufficient for the cutting action. Essentially, the lifting cams provide an accurate wire feed and the holding cam insures time for the cutting step after the feed has stopped.

It will be appreciated that many modifications may be made in the construction within the principles of this invention, such as an interchange in locations and relationships of the various cams and their followers, and the manner of mounting the feed rolls and providing for their relative separation. It is therefore to be understood that the above disclosure of the essential principles of this invention and of a preferred embodiment thereof is not to be interpreted as imposing limitations except those required by the appended claims.

I claim:

1. A wire coiling machine having coiling tools comprising a radially movable feed roll and a roll cooperating therewith which are arranged to grip a wire therebetween and feed it to the tools, cam mechanism including two lifting cams and a follower which act successively, one to lift the movable feed roll from the wire and the other to lfl lower it into feeding engagement therewith, means to shift the follower and lifting cams relatively to cause said lifting and lowering of the movabie feed roll, a supplemental holding cam and followerwhich' hold the feed roll lifted during said shifting movement in the interval between the operations of said lifting cams, and power mechanism for rotating the holding cam at .a slower angular rate than that of the feed roll lifting cams.

2. A wire coiling machine having coiling and cutting tools comprising two relatively separable feed rolls arranged to grip and feed a wire to the tools, two rotatable lifting cams for lifting and lowering the feed rolls relative to the wire, a laterally shiftable cam follower arranged to engage either of said cams, a control cam which serves to shift the follower so that one lifting cam-may separate the feed rolls and the other may subsequently bring them into a wire feeding engagement, and a holding cam and follower cooperating with the lifting'cams to hold the feed rolls separated during the period of shifting the lifting cam follower.

3. A. machine according to claim 2 comprising power mechanism for driving the control and holding cams slowly and for rotating the feed rolls and lifting cams through a plurality of turns for one revolution of the control and holding cams.

4. A machine according to claim 3 comprising a change speed mechanism which serves to drive the holding and control cams at a predetermined selectable rate and the feed rolls and lifting cams at a higher and controlled rate.

5. A machine according to claim 3 comprising a camshaft which rotates the control and holding cams and change speed mechanism connecting the camshaft with the feed rolls and lifting cams which serves to rotate the feed rolls and lifting cams through a plurality of turns for each rotation of the camshaft.

6. A wire coiling machine having coiling and cutting tools comprising two rotatable feed rolls for feeding the wire, shafts therefor, one feed roll being liftable away from the wire, two spaced lifting cams fixed on the shaft of one roll, a shiftable follower on the other shaft movable laterally from engaging one cam through an inoperative position to engagement with the other cam, said cams respectively cooperating with the follower to raise and lower the liftable roll from contact with the wire, a camshaft, a holding cam and a control cam on said shaft, means associated with the control cam for shifting said follower from one lifting cam to the other, means including a follower associated with the holding cam which maintains the feed rolls separated during the period in which the shiftable follower is moved, and power mechanism for driving the feed rolls through a multiplicity of turns per revolution of the camshaft.

7. A machine according to claim 6 comprising a speed change mechanism interconnecting the camshaft and feed rolls which causes the feed rolls to revolve through a plurality of turns and feed a predetermined length of wire during a single revolution of the camshaft so that the length of coiled wire'may be varied for each rotation of the camshaft.

8. A machine according to claim 6 in which the control cam has adjustable high and low portions serving to' position the lifting cam follower successively opposite to the two lifting cams and an intermediate cam portion which positions the follower between the cams, and the holding cam has relatively adjustable parts providing a high portion of adjustable length which holds the feed rolls separated for a predetermined time while the lifting cam follower passes between its cams and a low portion which insures that the feed rolls engage the wire for a predetermined period.

9. A wire coiling machine having coiling and cutting tools, two feed rolls arranged for gripping and feeding a wire to the tools, a shaft for one feed roll mounted to move the roll radially away from feeding engagement with the wire, two lifting cams on the shaft of the movable roll, an axially slidable follower arranged to be moved successively into positions opposite the cams, said lifting cams having their high portions so spaced angularly that they operate successively to separate the feed rolls and then after a predetermined interval to return them into wiregripping engagement, at camshaft, a control cam and a holding cam on the shaft, means whereby the control cam causes the lifting cam follower to be shifted from one lifting cam to the other, means including a cam follower associated with the holding cam which serves to maintain the feed rolls separated during the shifting of the lifting cam follower, and power driven speed change mechanism for rotating the feed rolls and the lifting cams at a given rate and the camshaft at a slower and predetermined adjustable rate, so that a predetermined variable length of wire may be coiled.

References Cited in the file of this patent UNITED STATES PATENTS 87,555 Foskett Mar. 9, 1869 1?. Sleeper Mary 14, Larsen Sept. 16, Sleeper Apr. 17, Van Orrnan Ian. 15, Van Orman Nov. 24, Bleuel July 10, Vinar Oct. 10, Bleuel Nov. 14, Blount Oct. 19, Prentice Mar. 7, Blount Oct. 10, Bergevin Nov. 6, Halvorsen Dec. 7, Wunderlich July 22,

FOREIGN PATENTS Great Britain May 1,

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