US3161481A

US3161481A - Fabric drying machine with timer control

Info

Publication number: US3161481A
Application number: US142863A
Authority: US
Inventors: James D Edwards
Original assignee: Borg Warner Corp
Current assignee: Borg Warner Corp
Priority date: 1961-10-03
Filing date: 1961-10-04
Publication date: 1964-12-15
Anticipated expiration: 1981-12-15

Description

` Dec. 15, 1964 J. D. EDWARDS FABRIC DRYING MACHINE WITH TIMER CONTROL 13 Sheets-Sheet 1 Filed Oct. 4, 1961 @525A Imp?! Dec. l5, 1964 J. D. EDWARDS 3,161,481

FABRIC DRYING MACHINE WITH TIMER CONTROL Filed Oct. 4, 1961 13 Sheets-Sheet 2 Dec. 15, 1964 J. D. EDWARDS 3,161,481

FABRIC DRYING MACHINE WITH TIMER CONTROL.

Filed Oct. 4, 1961 13 Sheets-Sheet 5 fnz/en-o" `fermes D Edwards @wa ma@ Dec. 15, 1964 J. D. EDWARDS FABRIC DRYING MACHINE WITH TIMER CONTROL Filed Oct. 4, 1961 13 Sheets-Sheet 4 .DNN www.

NNN

fnz/enforj Jama Edy/afa@ Dec. 15, 1964 J. D. EDWARDS 3,161,481

FABRIC DRYING MACHINE WITH TIMER CONTROL Filed 001i. 4. T1961 13 Sheets-Sheet 5 @55 fri-7W Dec. 15, 1964 .1. D. EDWARDS 3,161,481

FABRIC DRYING MACHINE WITH TIMER coNTRor. Filed oct. 4. 1961 l 1s sheets-sheet e Dec.'15, 1964 J. D. EDWARDS FABRIC CRYINC MACHINE WITH TIMER CONTROL l5 Sheets-Sheet 7 Filed Oct. 4, 1961 Dec. 15, 1964 J. n. EDWARDS FABRIC DRYING MACHINE WITH TIMER CONTROL 13 Sheets-Sheet 8 Filed OC. 4, 1961 Dec. 15, 1964 J. D. EDWARDS FABRIC DRYING MACHINE WITH TIMER CONTROL.

Filed oct. 4. 1961 13 Sheets-Sheet 9 fnverzor'.' Jamesf'dwards Dec. 15, 1964 J. D. EDWARDS FABRIC DRYINC MACHINE wrm TIMER CONTROL.

Filed Oct. 4, 1961 13 Sheets-Sheet 10 fnvezz'or/ James Edwards Mag Dec. l5, 1964 J. D. EDWARDS 3,161,481

FABRIC DRYING MACHINE WITH TIMER CONTROL Filed Oct. 4, 1961 1s sheets-skneet 11 fzverzZLo-t' James Edwards k www@ 1s sheets-sheet 12 MA Cif/NEI Dec. l5, 1964 J. D. EDWARDS FABRIC DRYINC MACHINE WITH TIMER CONTROL Filed oct. 4, 1961 @T252 frzz/enzlor.' fame Edwards TEMP. 5W

.SOLVENT LEVEL Dec. 15, 1964 J. D. EDWARDS FABRIC CRYINC MACHINE WITH TIMER CONTROL 13 Sheets-Sheet 13 Filed OCt. 4, 1961 fnl/67121071' kfame Edward? United States Patent tiee dli Patented Dee. 15, 1964 Illinois Filed st, 4, 1961, Ser. No. 142,853 Claims. (Cl. 34-45) This invention relates to a fabric-drying machine and more particularly to a new and improved control arrange-` ment for such machine.

An object of the invention is to provide a new and irnproved control arrangement for a fabric-drying machine.

Another object of the invention is to provide a new and improved control arrangement for a fabric-drying machine and providing for automatic opeartion of fabric-drying cycles of the machine.

Another object of the invention is to provide a new and improved control arrangement for a fabric-drying machine having a master or interval timer for controlling electrically-operated components energizable in a predetermined timed sequence or intervals to providerautomatic fabric-drying cycles of the machine, and a subsidiary or sub-interval timer for performing separate control functions duringV certain time intervals of the master timer. Y

Another object of the invention is to provide a new and improved control arrangement for a fabric-drying machine in which a master or interval timer controls electrically-operated components in an automatic sequence of intervals to provide diierent drying periods, and subsidiary or sub-interval timers jointly controlling inter-related electric circuits to the interval timer and also the components, with said sub-interval timers having diiferent control functions.r

Another object of the invention is to provide a new` and improved control arrangement for a fabric-drying machine and in which a sub-interval timer periodically advances an interval timer, controlling electricallyoperated components, during a fabric-drying operation involving a sub-interval timer expanding a predetermined time interval of the interval timer by the sub-interval time inactivating the interval timer motor and thereafter periodically activating the motor to delay normal operation of the interval timer and thus Vincrease the normal time interval period of the interval timer; and a thermostat, responsive to the heated air circulated in the machine to dry the fabrics, controlling the operation of the sub-interval timer.

Another object of the invention is to provide a new and improved control arrangement for a fabric-drying dry cleaning machine and in which a sub-interval timer periodically advances an interval timer, controlling electrically-operated components, during a fabric-drying operation involving removal of water moisture from the fabric, prior to the dry-cleaning operation, and during which operation, the sub-interval timer operates to stop the interval timer and stopping the interval timer periodically to expand the time interval of the interval timer and thereby the drying operation.

Another object of the invention is to provide a new and improved control arrangement for a fabric-drying machine having heating means and heated air circulation means and in which a sub-interval timer controls the operation of an interval timer for a predetermined period of a drying operation to lengthen the normal time interval of the interval timer, the interval timer operation being controlled by a thermostat responsive to a predetermined air temperature in the machine to prevent operation of the heating means and air circulation means and to simultaneously deenergize the interval timer and energize the sub-interval timer to periodically advance the interval timer until the temperature falls below said predetermined temperature when the thermostat is operative to reenergize the interval timer and deenergize the sub-interval timer.

Still another object of the invention is to provide a new and improved electrical control arrangement for a fabric-drying machine including an electrical heater to heat the air in the machine, and an electrically-operated heated air-circulation means to dry the fabric, an electrical control circiut for said heater and air-circulation Vmeans and embodying a master or interval timer, and a thermostat responsive to a predetermined air temperature to deenergize the heater in the event of interruption of air flow during the drying cycle, due to mechanical or electrical failure of the air circulation means, fabric blocking of air circulation, or other adverse-drying conditions, and an electrically-operable `subsidiary or subinterval timer engerized by operation of the thermostat to deenergize the air-circulation means, the subsidiary timer, when energized, being effective to energize the master timer periodically to advance the master timer, until the air temperature is below the said predetermined temperature and the air flow condition is remedied, or, if the condition cannot be remedied, for example, when mechanical failure of the air-circulation means occurs, to continue periodic energization of the master timer for the remainder of a time interval of the drying cycle.

Another object of the invention is to provide a new and improved control arrangement fora fabric-drying machine including an electrical heater and electricallyoperated heated air-circulation means to dry the fabric, the control arrangement having a master or interval timer having a motor operable to normally advance a cam bank controlling switches arranged in electrical circuits for electrically-operated components of the machine, including the electric heater and heated-air circulation means, during a drying time interval of the machine, and a plurality of subsidiary or sub-interval timers having motors to advance cam banks for actuating switches of the subinterval timers controlling electric circuits for "energizing and deenergizing the interval timer, the interval timer motor being effective to operate certain interval timer switches to deenergize the timer motor and to energize a first sub-interval timer motor to open and close one of its Y switches to periodically energize the interval timer motor for expanding the normal time period of the drying interval of the interval timer; operation of a thermostat responsive to a predetermined temperature of the heated air circulating in the machine deenergizing the heating means and energizing the motor of the second. sub-interval timer to deenergize the air-circulating means, Vand the second timer motor being effective to cause the cam banlcof the second timer to periodically energize the interval timer for expanding the normal time period of the drying interval of the interval timer until the air temperature in the machine is below the predetermined temperature to etect Y operation of the thermostat to energize the heating means and air circulation means and also to deenergize the second sub-interval timer motor and reenergize the interval timer motor for the remainder of the drying interval, the electric circuits controlled by the sub-interval timer motors for energization of said interval timer including switches periodically closable by the sub-interval timers for energizing the interval timer with the switches being arranged in parallel in the circuits, the switch of the first sub-interval timer being inoperative to energize the interval timer motor during energization of the second sub-interval timer motor.

These and other objects and advantages of the invention will appear more clearly from the following specifi- 3 cation in connection with the accompanying drawings, in which:

FIG. 1 is a front elevation of the dry cleaning system embodying the invention, including two combination cleaning and drying machines;

FIG. 2 is a top plan view of the system illustrating the uid supply arrangement and including a filter;

FIG. 3 is a diagrammatic perspective view of the system shown in FIG. 2;

FIG. 4 is a diagrammatic rear view of the system, certain parts of the system being shown in changed position from that of FIGS. 1-3 to more clearly illustrate a feature thereof;

FIG. 4A is a sectional view of a portion of the uid supply system and also showing details of a fluid level device;

FIG. 5 is a vertical sectional view of one of the machines shown in FIG. l, said section being taken on line 5-5 of FIG. 1, and illustrating interior parts of the machine including a fluid-containing receptacle, a fabricreceiving basket, and an air-circulating fan, and means for rotatably mounting the basket and fan on the receptacle;

FIG. 6 is a rear elevational View of the machine shown in FIG. 5, illustrating the drive mechanism for basket and fan rotation and including a transmission providing difn ferent speeds of rotation of the basket;

FIG. 7 is an enlarged sectional view of the receptacle, basket and fan and mounting means therefor of FIG. 5, said section being taken on line 7-7 of FIG. 6, looking in the direction of the arrows;

FIG. 8 is a greatly enlarged sectional view of the basket and fan mounting means shown in FIGS. 5 and 7, said section being taken on line 8-8 of FIG. 6, looking in the direction of the arrows;

FIG. 9 is a sectional view of the transmission shown in FIG. 6, said section being taken on line 9 9 of FIG. 6;

FIG. 9A is a front elevation of the electric drive motor unit including drive pulleys and clutch, said view being taken on line 9A-9A of FIG. 6 and being partly in section to more clearly illustrate the structure thereof;

FIG. 10 is a side elevational view of the lower half of the machine including a cleaning fluid storage ta-nk, said view partly being in section to more'clearly illustrate the structure thereof;

FIG. 11 is a fragmentary top plan view of the controly valve arrangement mounted on the top of the fluid storage tank;

FIG. 12 is a view illustrating an air-venting vacuumbreaker valve shown in FIG. 11;

FIG. 13 is a side elevation of one of the control valves, taken on line 13-13 of FIG. 14;

FIG. 14 is an end view partly in section, of the valve of FIG. 13, said view being taken on line 14-14 of FIG. 13;

FIG. l5 is a fragmentary sectional view of the valve of FIGS. 13 and 14, said section being taken on` line 15-15 of FIG. 14;

FIG. 16 is a diagrammatic view of the control valve arrangement shown in FIG. 11;

FIG. 17 is a sectional view ofy a separating deviceA for different fluids, said section being taken on line 17-17 of FIG. 11;

FIGS. 18 and 19 are vertical sectionalI views off one of the two identical air shutters, in the form of poppet valves, shown .in FIG. 6 and provided for removal of` cleaning fiuid fumes from and about the machine at the conclusion of the drying cycle of the dry cleaning machine, FIG. 18 illustrating the closed position of the valve andFIG. 19 illustrating the open position of the valve;

FIG. 2O is a diagrammatic view of the electrical control arrangement of the dry cleaningV machine and including sequentially-controlled cam-operated switches;

FIG. 21 is a cam sequence chart illustrating the cleaning and drying cyclesv of the dry cleaning machine.

Referring now to the drawings, FIGS. 1, 2, 3, and 4 illustrate an improved dry cleaning arrangement particularly, out not necessarily, adapted for a plurality of combination fabric-cleaning and drying machines, two of which are shown and generally identified as I and II.

The cleaning fiuid supply system utilized with the machines has been designed to provide a constant iiow of clean, filtered cleaning fiuid or solvent, such as perchlorethylene, to each machine during the fabric-cleaning cycle, each machine having an overiiow arrangement to expel the soiled solvent from the machine to a solvent storage base tank of the machine for flow of the solvent to a pump and then to a filter for removing soil and other impurities from the solvent and for recirculation of the cleansed solvent. The filtered solvent is supplied to each machine by a manifold providing a metered quantity of cleaning solvent to each machine with a proper solvent level or height being constantly maintained in the machines by the location of theV solvent overflow pipe in the machine. This feature is important as each machine includes a fabric-containing basket rotatable about a horizontal axis and designed to permit the fabric to be picked up from the solvent, lifted above the solvent and dropped back a maximum distance into the solvent. to provide the best flushing action of the solvent through the fabric and greater dispersion and elimination of the soil from the fabric.

Prior to describing the fiuid supply system, reference is made to FIGS. 1 to 4, inclusive, illustrating machines I and II. As each of these machines are identical in construction and operation, it is believed the description of one of the machines (machine I) will be adequate to an understanding of each machine structure and operation. Identical structural parts of machine II are designated with the same numeral'as machine Ibut with the sufiix` a. The structure of machine I is illustrated in FIGS. 5-10, and referring first to FIGS. 5 and' 6, the machine comprises a cabinet 10 receiving a cleaning fluid-containing receptacle ink theV form of an imperforate cylindrical casing or tub 11 having a front wall 12.and a rear-wall' 13. The tub 11 is supported by a suspension system of the inverted pendulum type generally indicated at A mounted on a base structure B, the suspension system A comprising pivots C and D attaching the tub to the base structure B for operating movement of the tub, the pivots C and D being directly below the center line of the tub and being connected to the bottom of the tub by a pair of front and rear brackets, one of which is shown at E. Control springs (not shown) can be located on opposite sides of the tub, and these springs, in conjunction with a hydraulic damper assembly are effective to control the tub movement during rotation of a cylindrical fabric-containing basket or drum 18 at high speed with an unbalanced load of fabric, such as clothes, in the basket. The suspension system arrangement of the tub is more particularly shown and described in U.S. Patent 2,978,892, issued April 11, 1961. The front wall'12 of the tub 1-1 is pro` vided with anaccess opening 14 and a corresponding, opening 15 is in the cabinet 10. A fiexible corrugated gasket 16 extends between and connects the annular portions of the front walls of the tub and cabinet defining: two openings, and the cabinet is provided with a door 17 to close the opening in the tub.

The basket or drum 18 is disposed in the tub 1-1 for the reception of fabric to be cleaned and dried and the basket is supported by means of a spider 19, forming a portion of the rear wall of the drum, on a sleeve shaft 20 rotatably mounted on the rear wall 13 of the tub 11 for rotation ofthe drum 18. A pulley 21, fixedly secured to the shaft 29, is adapted to be rotated by a belt 22 in driven relation to a driving pulley 23 connected to the driven shaft of a two-speed transmission T driven by an electric motor M. Briefly described, the two-speed transmission is controlled by clutches, one of which is selfenergizing and the other clutch is solenoid-controlled to provide low speed'for slow lrotation of the basket or high speed for rapidly rotating or spinning the basket. When the solenoid is deenergized, its clutch is ineffective and power flow is through the self-energizing clutch to provide low s'peed to tumble the'basket during a portion of a cleaning operation and during the drying operation, and when the solenoid is energized, its clutch is operative and the self-energizing clutch becomes inoperative, so that the transmission is conditioned to provide a relatively high speed to rotate the basket, for example, during the extraction of the cleaning fluid from the fabric.

More particularly, and referring to FIGS. 7 and 8, the tub 11 has the radially inner edge of its rear wall 13 connected to two

annular support housings

24, 24 by screws 25, the

housings

24, 24 having radially inner ends overlapping and confining therebetween an outer race 26 of a ball bearing assembly, with the inner race 27 fixed to the sleeve shaft for rotatably supporting the shaft 20. The front end of the shaft 20 is connected to a hub of the basket provided by the radially inner edge of the rear wall of the basket and two retaining rings 2S, 28 connected by screws 29 so that rotation of the shaft 2t), by pulley 21 keyed as at 30 to the rear end of the shaft, will rotate the basket.

A blower fan 32 is supported for rotation by the sleeve shaft 20 including a shaft 33 extending through and mounted on needle bearings between the shafts, the front end of the shaft 33 being connected to the hub 34 of the fan 32 by a bolt 35 threaded into the hub and engaging the shaft 33. The rearward end of the shaft 33 extends outwardly of the shaft 20 and receives the hub 36 of a pulley 37 for rotating the fan independently of the basket, the pulley hub 36 being connected to the shaft 33 by a bolt 38 threaded into the hub and engaging the shaft 33.

The basket and fan shaft mounting assemblies also comprise grease seals and thrust washers as clearly evident from an inspection of FIG. 8.

Referring now specifically to FIGS. 6 and 9 for the structure and operation of the drive mechanism including the transmission T, the transmission comprises an input sleeve shaft 40 having a pulley 41 connected by a belt 42 to a pulley 43 driven by the electric motor M. The shaft 40 has an input pinion 44 meshing with a gear 45 fixed to a countershaft 46. A gear 47 is rotatably supported on the countershaft 46 and may be coupled to the countershaft for rotation therewith by a selfenergizing clutch spring 48 of well known type, surrounding the countershaft between

gears

45 and 47. The countershaft gear 47 meshes with a gear 49 lixed to the output shaft 50. A clutch spring 51 surrounds the input shaft 40 and is positioned between the gear 49 and pinion 44, the clutch spring having a tab 52 at one end of its helically wound coil engageable with a plunger 53 actuated by av solenoid 54.

In operation, the basket may be slowly rotated to tumble the fabric in the cleaning fluid in the tube. As the solenoid is deenergized, its plunger 53 engages the tab 52 of the clutch spring 51 to prevent operation of the clutch spring 51 to couple the gear 49 and spring 51, and the hub of the gear 49 turns freely within the clutch spring 51. Power ilow from the motor is transmitted to the pulley 41 and thereby input shaft 40 and input pinion 44. Pinion 44 rotates gear V4S on the countershaft and gear 49, keyed to the output shaft 50, to drive pulley 23 to rotate the basket at slowv speed.

During the Huid-extraction period of the cleaning cycle, the basket rotates rapidly to centrifuge the uid from the fabric. For this purpose, the solenoid 54 is energized to remove its plunger S3 from the tab 52 of the clutch spring 51 so that power iiow will be from the input shaft 40, input pinion 44, and, as the clutch spring 51 is effective at this time to couple the input pinion 44 and gear 49, gear 49 will be rotated to drive the output shaft 50 to rotate the basket at high speed. It will be apparent, due to the sizes of the input pinion 44 and gears 45, 47, and 49, that the gear 49 will drive the gear 47 at such 6 high speed that the clutch spring 48 will overrun to pre-r vent power flow through the countershaft and gear 45 to the gear 44.

Referring to FIG. 5, the cylindrical wall of the basket 1S is perforated having a plurality of openings 55 therein. The basket front wall is provided with an opening 56 spaced from the access opening in the front wall 12 of the tub 11. An annular ring 57 is suitably attached to the front wall 12 of the tub 11, a second annular ring 58 is attached to the ring 57 and spaced therefrom by pins or rivets 59. The rear wall of the basket 1S is provided with a pocket P formed by the legs of the spider 19 merging with the cylindrical portion of the basket extending about the rotational axis of the basket, the pocket P having a plurality of openings 60 defined by the legs of the spider 19. The front of the basket 18 has a cylindrical flange 61 defining the opening 56, and the front wall 12 of the casing 11 has a pair of bearing rollers 62 secured thereto to support the front of the basket.

Air circulating means, in the form of the suction type blower fan 32, is rotatably mounted in a pocket P in the rear wall of the basket 18. The fan 32 has a plurality of curved blades and, as previously described, is driven by a belt and pulley arrangement, the pulley being indicated at 37 and the belt being indicated at 63 to be driven by the pulley 64 of the electric motor M. Referring to FIGS. 6 and 9A, operation of the fan is controlled by a clutch generally indicated at 65 and including a clutch spring, surrounding the motor drive shaft 66 and located within a housing 67, the spring having an end tab 68 seated within a recess in the housing, and the housing having an outwardly projecting finger 69 engageable with the end of a plunger 70 of a solenoid 71 so that, when the solenoid is energized to move its plunger from the spring tab 68, the clutch spring is effective to couple the pulley 64 to the drive shaft 66 to eect drive of the pulley, and thereby the fan, by the motor. The solenoid 71 is mountedhon a bracket 72 fixed to the motor casing which is mounted on a plate secured to the tub, as shown in FIG. 6. The solenoid is energized to eiiect rotation ofthe fan during the drying operation.

In FIGS. 5 and 6, an annular heater assembly '73'is iixedly secured to the front wall 12 of the tub 11 and includes an aluminum body having embedded annular Calrod type heating coils 74 and 75 suitably connected to a supply of electric current controllable to energize one or the other, or both, heating coils of the heater assembly during the drying operation of the machine. During this drying operation, the basket is rotated slowly to tumble the fabric and the fan is effective to cause the heated air to circulate and iiow between the tub and basket and around the basket and through the perforations in the basket to dry the clothes in the basket. The heated air is then drawn through a perforated plate 76 and lint screen S by the fan and through the pocket P of the basket and through the openings 60 dened by the spokes of the basket rear wall Ispider 19 and into the space between the basket and the rear wall 13 of the tub to be recirculated in the machine. As it i-s con? templated the machine will be used with a dry cleaning solvent, such as perchlorethylene, vaporizable during the drying operation, a condenser, generally indicated at 77, is positioned adjacent the lower portion of the wall 13 of the tubV 11 for condensation of the solvent vapors produced by the drying operation. Moreparticularly, the condenser 77 comprises a plate of arcuate configuration and having upper and lower connected passages 78l and 79 with the upper passage 78 being connected t0 a water inlet hose 80, the passages 78 and 79'of the condenser conducting the water t0 a hose 81 leading to a drain exteriorly of the machine. As seen in FIG. 5, the condenser is mounted on the inside of the rear wall 13 of the casing 11 by securing means 82. The hose 811 extends to a valve CV controlled by a solenoid CS which, when energized, opens the valve to permit cold water to enter and flow through the hose S' into and through the condenser into the hose S1.

Referring now to FIGS. 1 `and 6, the drum 11v has the upper portion of its rear wall provided with air shutters in the form of air inlet and exhaust poppet valves, generally indicated at 83 and S4, operative to permit air to enter the tub 11 through valve 83 so that all solvent vapors may be flushedk and' dishcarged from the machine through the valve S4 at the end of the drying cycle of the machine to be carried away by a Ventilating system. The Ventilating system includes an air intake opening in wall 13 of the tub 11, through which flow'of air into the machine is controlled by valve 83', the air entering and mixing with the solvent vapors andthe mixture then being discharged through the valve S4 into an air duct 85 and a plenum duct 86 and throughv an exhaust duct 87 into the atmosphere exteriorV of the building. The duct S6 has a blower 83, including an electric motor 89 and a fan 90, for causing air flow into and through the machine and into the Ventilating system ducts. During operation of the blower fan, any vapor-laden air about the machine is also drawn through a` scavenger duct 91 extending upwardly into the duct S6 for exhaust by the blower fan.

The poppet valves 83 and S4 are identical and, for this reason, a description of the structure and operationof only one of these valves (valve 84) will be made. The valve 841s shown in detail in FIGS. 6, 18 and 19. This valve comprisesivalve body 109 having a plate portion 110 with an annular flange 1113 fitting within an opening in the tub rear wall 13 and providing a seat for a flexible seal 112 to prevent air flow between the three spaced legs 113 of the valve bodyl from the machine. The seal is normally held engaged with the flange 1114 by anl activating-'rod 114V slidably mounted within a sleeve 1-15 secured to the radially inner ends of the legs 113, thesleeve 115 having a surrounding spring 116 compressed between the seal 12 and the valve body. The rod 114 is connected to a link 117 which is connected tovone end of a U-shaped lever 118` centrally pivoted at 119to upstanding. ears on-y a tubular. extension4 collar 120, the other end of the lever 11S being connected to a spring 121 coupled to the plunger 122 of a solenoid 123 mounted on a bracket 124 fixed to the tub rear wall 13. The valve is shown in closed position in FIG. 18, the solenoid being energized at this time. Upon deenergization of solenoid 123 as shown in FIG. 19, the plunger 122 will move downwardly to cause spring 116 to expand to move seal 112 from the flange 111 to thereby permit air to flow from the tub 11 through the valve 84 and into the duct 85. When the solenoid is energized, the valve S4 will close, as shown in FIG. 18, as the link and lever arrangement will cause seal 112 to again seat aganist the flange 111, the spring 116 being compressed at this time.

Referring now more particularly to the closed fluid supply system, machine I has its base structure B supported above and on a rectangular solvent storage tank indicated at 152, the tank including a top plate 153 enclosing the top of the tank and on which the machine is mounted by means of brackets 154, and bolt and nut securing and leveling devices, such as illustrated at 155. The flat bottoms of the tanks of machines I and II are positioned on a floor F that is smooth, flat, and level with no rise or drop in elevation from one end of the row of tanks to the opposite end for insuring the proper flow and correct distribution of the solvent to the tank assemblies as will be later described. Each tank extends rearwardly of its machine, as will be obvious from the drawings, and the top plate 153 of the tank is provided with a circular opening 156 for receiving a basket-type filter 157 formed of mesh wire screen and extending downwardly into the tank, the filter having its upper rim 158, defining the open top thereof, extending over and engaging the edge of the opening 156 of the top plate 153 ot the tank to removably position the filter within the tank. A cylindrical header 159 (FIG. 10) is positioned on and may be welded to the top plate 153, the header having its bottom edge inwardly turned and extending beneath the rim 158- of the filter 157, the header also extending upwardly and' having its upper end closed by a removable cover 160` having sufficient weight to insure tight sealing engagement with the upper end of the header to prevent the. escape of solvent vapors from the tank and filter. The cover 160 is provided with a handle 161 for removal of the cover to permit access to the filter 157 which may be raised from its position within the tank and through the header for cleaning lint from the filter, as shown inl dotted lines in FIG. 10. The header 159 is formed with a tubular portion 162 extending laterally thereof and provided with a reduced end portion for attachment to a tubular connector 163 having one end receiving a hose 164. As seen in FIGS. 5 and 10, the hose 164 extends along the top of the tank and upwardly for connection to a tubular extension 165 secured to the tub 11 and defining-an opening within the cylindrical wall of the tublocated a predetermined distance above the bottom of theV tub for a purpose to be described more fully hereinafter.

As seen more particularly in FIGS. 11 and l2, the opposite sides of the tank have substantially large, tubular extensions 166 and' 167, the tubular extension 166 providing a' fluid inlet passage for solvent entering the tank and thetubular extension'167'providinga fluid outlet for the solvent from the tank. The tank has a central baille 168 around whichv the solventl flows, as indicated by the arrows in FIGS. 1l and' 12, and also abaffle 169 connectedl t'o the` side wall' of the tank adjacent the outlet tubular extension 167, the baffles being effective to prevent settling of impurities in the tank.

Referring to FIG'. 5, there is aI sump elbow 1-70 located in and` connected to the bottom of the tub of the machine, the elbow 170 having a` laterally extending tube receiving one end of' a hose 171. The opening in the elbow 170 is covered' by a screen 172 providing a pin and button trap.

Solvent is supplied to the tub of the machine through the hose 171 and, asfthe solvent enters the tub, the solvent rises to" a predeterminedy l'evel defined by the opening 165 in the side wall of the tub and through whichv the solvent overflows from the. tub into the hose 164 and through the connector 163 and tubular extension 1162 of the header 159y into the lintv filter basket- 157,` lint being filtered from the solvent and the solvent then being added tofand mixed with solvent circulating through the tank from the inlet opening of the tank, provided by the tubular extension 166 ofthe tank, to the outlet opening of gie tank, provided by the tubular extension 167 of the tan Referring now more particularly to FIGS. 2, 3, and 4, the tubular fluid outlet extension 167 of the base tank of machine I is connected to a pipe 173 effective to direct the soiled solvent to a circulating pump 174, the pump causing the solvent to be forced under pressure through an open4 check valve 175 and a pipe 176 into the bottom of the filter 177. The filter 177 may employ screens covered with a filtering compound for filtering impurities from the solvent. The soiledsolvent enters the filter 177, adjacent the bottom thereof, through the pipe 176, and filtered clean solvent flows from an outlet at the top of the filter into a pipe 178 which, as shown in FIGS. 3 and 4, is elevated above the top ofthe filter.

Proceeding further with the description of the fluid supply system, it will be seen from FIGS. 2, 3, and 4, solvent flows from the filter 177 into the pipe 178 which extends downwardly through a water-cooled heat exchanger 210 and thereafter turns at a right angle in a horizontal plane for delivery of solvent to the horizontal pipe 211 connected to a horizontal manifold pipe 213. An inverted U-shaped assembly 212 includes a horizontal pipe 214 and two

vertical pipes

215 and 216, the pipe 213 being connected to pipe 211. The pipe 215 functions as a standpipe and is connected to pipe 213 and the solvent is forced upwardly through pipe 21S and flows into pipe 214 and then downwardly into the overflow pipe 216; pipe 215 terminating in a pipe 217 positioned in a horizontal plane below that of pipe 213. The pipe 217 has its outlet end connected to the inlet tubular extension 166a of the side wall of the solvent storage base tank 152e of machine II so that the filtered solvent flows into and through the base tank of machine II, as shown in FIGS. 2, 3, and 4, for mixture with the soiled solvent entering the tank from the overflow hose and the lint filter basket of machine II when maclnne II is in operation, the solvent then flowing through a pipe 218 connecting outlet tubular extension 166e with the inlet tubular extension 167 of base tank 152 of machine I for mixture with the soiled solvent overflowing the tub of machine I and for flow therethrough and the outlet tubular extension of tank 152 into the pipe 173 to the pump for recirculation through the filter, the assembly 212, and the storage base tanks of machines I and II. A vacuum breaker hose 219 is connected to the top of pipe 214 and also to the headers 159 and 159:1 of the storage tanks 152 and 152g as shown in FIGS. 2 and 3.

It will be apparent from this description that a substantially large volume of ltered clean solvent liows from the filter and heat exchanger through the manifold pipe 213 and pipes of the U-shaped assembly 212 to eifectively mix with the relatively small volume of soiled y solvent in the base tanks 152 and 152g of machines I and II during the cleaning operation. The mixture of soiled and clean solvent then flows through the pipe 173 into the suction side of the circulating pump 174 for movement under pressure by the pump into the filter, the clean solvent then being again returned to the base tanks, to` thereby insure a continuous circulation of the solvent in a manner'providing a constant supply of clean filtered solvent tothe machines.

A feature of the fluid supply system is that, after the clean solvent flows out of the upper end of the fil-ter 177 and the heat exchanger 2119, the solvent flows, by gravity, through the pipe 211 and through

pipes

213, 215, 214, 216, and 217 into the base tank of machine II. More particularly, this advantageous feature contemplates that the pump 174 forces the soiled solvent into the filter 177 under pressure to filter the solvent, the cleaned solvent being raised to an elevated position for flow out of the top of the filter. As the solvent in the iilter is only under pressure, the solvent thereafter iiows `from the filter and into the manifold pipe 213 and pipes of the assembly 212 by gravity and into the base tank of machine II and thence into the base tank of machine I, the solvent continuing to flow by gravity into the machines and flowing out of the machines and back to the pump. It is emphasized that this improved iiuid supply system contemplates that none of the `iiuid lines leading to or from the machines are under pressure Afrom thepump. It is not necessary to mount the machines on a slope or to incline the pipes. The slope is in the solvent that `causes it to flow by gravity. Due to the employment of the gravity flow of solvent through pipe 211 and the manifold pipe 113,Wstandpipe 215, pipe 214, and overflow pipe 216, this gravity flow system not only allows metered solvent supply feed selectively to each machine, but provides a balanced feed to one or more machines so that they receive equal amounts of solvent. In effect, the gravity flow of the solvent (the slope of the solvent causing the iiow) through the machines is based on the concept .that any fluid will seek to lind its own level and once that level has been established, the fluid flowing, for example, into machine II has a level deeper than that of the level of the fluid in machine I causing the flow of the liuid by gravity through the machines and back to the circulating pump. The function of the standpipe 215 is to provide a pressure,`caused by an active head of solvent, for feeding solvent by gravity into the tanks and tubs of the dry cleaning machines I and II.

Solvent is fed into the tub of each machine by the manifold pipe 213 which, as shown in FIGS. 2, 3, and 4, is provided with downwardly extending tubular portions 220 and 220e connected respectively to hoses 221 and 221:1 which are connected to identical diverter valve assemblies 222 and 222e. Each diverter Valve assembly comprises three valves, respectively identified at 223, 224, and 225 in FIG. 1l of similar construction but having different control functions during cleaning and drying cycles of its machine. To describe the structure of each valve assembly, reference is made to valve assembly 222, and its

valves

223, 224, and 225, shown in FIGS. 11 and 13-16. For a description of one of the

valves

223, 224, and 225, reference is made to FIGS. 13, 14 and 15. More particularly, the valve 225 functions to direct solvent from the hose 221 into and through the valve assembly 222 and into the hose 171 and the tubular extension 170 of machine I, the solvent flowing into the machine until it reaches a level equal to the height of the overflow opening in the tub of the machine for iiow therefrom into thekhose 164 and into the filter basket and storage base tan The introduction of air, at substantially atmospheric pressure, into the stand pipe 215 through the hose 219 causes a liquid-air interface in the

overflow pipes

214 and 216 that establishes the level of the solvent at the overflow point. The head of solvent feeding the machines is the distance from the liquid-air interface to the fluid inlet valves 225 of the valve assembly 222 and/or the valve assembly 22212. The head is substantially the same throughout the manifold pipe 213; however, the head is slightly higher at the filter end of the manifold pipe. This slight variation in head represents the amount of pressure drop through themanifold pipe due to its inherent internal restriction. The head in the solvent manifold pipe 213 can be referred to as the apparent depth of the solvent in the pipe, the variation in the head at different points in the manifold pipe represents the slope of the iiuid that causes. the iiow through the pipe.

All of the fluid in the system is under continuous flow at all times due to the pumping capacity of the filter pump 174. The base tanks 152 and 152:1, interconnected by the connecting conduit 218, represent an extension of the flow paths or pipes of the manifold and overflow arrangement. Removal of a quantity of iiuid from the manifold pipe 213 represents'removal of fluid from the base tanks 152 and 152e since both the pipe 213 and the base tanks are in the same flow path. When a quantity of solvent is removed from the manifold base tank portion of the fluid circuit and introduced into the tub of the machine, an equal quantity of air must be moved from the tub of the machine through the overiow pipe 214 past the check valve CV into the base tank 152 to maintain substantially atmospheric pressure throughout the system.

The gravity flow standpipe and fixed head feed arrangement has three primary advantages. First, since all portionsy of the manifold pipe 213 are under approximately the same head when the iill valves 225 of the valve assembly 222 and/or the valve assembly 222:1 open allowing fluid to flow from the manifold pipe into either or both of the machines I and II, the fixed head in the manifold pipe combined with the inherent internal restrictions of the fill hose, lill valve and iiow path into either or both of the machines gives a metered flow of lluid for cleaning. This condition is maintained as long as solvent supply exceeds solvent demand and the surplus fluid of supply, exceeding demand, flows over the overow pipe 216. At any time the supply exceeds the demand, there is no surplus iiuid flowing over the stand pipe 215 into the overiiow pipe 216 and the amount of fluid available is proportioned equally among the machines calling for fluid. Ari additional feature is that the rate of flow of the fluid supply may be less than that required for the number of machines connected to the fluid supply, allowing more economical use of cleaning machines in relation to the size of the filtration apparatus. For instance, the filter may be partially clogged with soil and only 30 gallons of fluid are available and flowing through the manifold pipe. Assuming eight machines are employed in the dry cleaning system and three machines are energized and call for uid, each machine receives approximately 9 gallons per minutes of fluid for cleaning the garments. The surplus fluid liows over the stand pipe into the overflow pipe to the base tanks of the machines. When the fourth machine is energized, no surplus fluid may ow over the stand pipe into the overflow pipe, the head in the standpipe fails and the contacts of a solvent level switch 267 close to energize Do Not Use lamps 266 on the backguards of any machines not in use. The 30 gallons per minute of available fluid or solvent supply is equally proportioned among the four machines energized resulting in 71/2 gallons per minute to each machine. As soon as one of the four machines stops calling for uid, a surplus of iluid supply exceeding demand will exist and fluid will llow over the stand pipe into the overflow pipe thereby opening the contacts of the solvent level switch and deenergizing the Do Not Use lamps on the machines, alerting the customer that the condition of fluid supply exceeds fluid demand and allowing another machine to be energized.

The solvent level switch device is shown in FIG. 4A and comprises a pipe 307 extending upwardly of pipe 213 and in fluid communication therewith and having its upper end projecting into and positioned within a casing 267a. It will be noted that the fluid level in the pipe 307 reflects any variations in the fluid level in the standpipe 215 continuously and proportionately. During static or changing levels of fluid in the pipe 307, contacts 267d and 267e of switch 267 may or may not be closed depending on the level of the fluid in pipe 307. In the event the level of the fluid in the pipe 307 is as shown in FIG. 4A, it will be seen that the switch contacts 267d and 267e are closed. The contacts 267e are iixed to the casing and have conductors C15 and C58 connected thereto, as shown in FIG. 20. The contacts 267d are fixed to a rod 267e which is connected to a cylindrical block 267b of aluminum guidingly movable vertically within the pipe 307 in response to the level of the lluid in this pipe and as also controlled by a tension spring 267f extending between and connected to the top wall of the casing 267e and contact 267d. More particularly, when the block 267b is above the low level of the lluid in pipe 307 and suspended by spring 2671, contacts 267d and 267e are closed. As the lluid level rises in pipe 307 and the block is immersed in the fluid, the block will be moved upwardly by the tension spring 267i to open contacts 267d and 267e. It will be apparent that this occurs due to the physical phenomena of the change in density of `the fluid and air mediums causing the fluid to exert an upward force or bouyancy on a body immersed or submerged in the fluid to thereby permit upward movement of the block by the spring to open the contacts of switch.

It will be apparent that the dynamic condition of solvent fluid flow through the manifold standpipe and overflow pipe, the injection of air through the vent hose 219, and the establishment of the liquid-air interface, deH termine the level of the solvent fluid in the manifold pipe can be compared to an elevated storage tank open to atmospheric pressure which always has a liquid interface that would establish the level of the solvent. The injection of air at substantially atmospheric pressure through the hose 219 into the stand pipe 215 and overflow pipe 214 results in a liquid-air interface under dynamic conditions that forms a static head the same height in the manifold. If a manometer were connected to the solvent manifold pipe 213, it would indicate a head or effective solvent fluid depth approximately equal to the center line of the pipe 214, and depending upon the solvent manifold pipe length, this head or effective depth would increase at points in the manifold pipe farther from the standpipe 215 to the filter end of the manifold pipe. For example; using a three inch diameter manifold pipe, which provides inherently low internal resistance to the ilow of 55 gallons per minute, the head was found to be two inches more 20 feet away from the manifold pipe than adjacent to the standpipe. This slight variation in head at different positions in the manifold pipe does not significantly affect the metering and ilow rate into the machines.

Referring to the valve assembly 222 in detail, the flow of the solvent through the valve assembly 222 is diagrammatically shown in FIG. 16 in which, briefly described, the fluid enters the assembly through the hose 221 and ows through the valve 225 into a common passage 226 through the valve assembly for all of the valves of the assembly,

valves

224 and 223, at this time, being ineffective to divert the solvent from the passage. Accordingly, as the valve 224 is open, the solvent passes therethrough and into and through the passage 226 to flow outwardly of the valve assembly and into and through the hose 171 into the tub of the machine during the fill and cleaning cycle of the machine. This ow of the solvent is diagrammatically illustrated in FIG. 16. During the drain and extraction periods of the cleaning cycle of the machine, the

valves

225 and 223 are closed and the valve 224 is open so that the solvent flows from the tub sump and through hose 171 into the passage 226 of the valve assembly and through valve 224 into the hose 252, connected to the header 159, for flow of the solvent into the storage base tank. During the drying cycle, the valve 223 is open and the

valves

224 and 225 are closed. The solvent vapors are condensed by the condenser 77 into liquid solvent which drains from the hose 171 into the passage 226 to ilow through open valve 223 into hose 253 connected to a solvent and water separator 254. A more complete description will be later given.

As each of the valves are identical in structure, it is believed that an explanation of one of these valves will be suiiicient and, for this purpose, referring to FIGS. 13, 14, and l5, it will be seen that, for example, the valve 224 is provided with a passage therethrough, forming a portion of the common passage 226 of the valve assembly, and including tube-

like extensions

227, 227 extending laterally from the valve body 228 and providing passages through

hoses

229 and 230 for solvent between the valve 224 and the

valves

225 and 223. The

tubular extensions

227, 227 of the valve 224 provide fluid connections to an interior valve chamber 231 of the valve body 228 through which the solvent flows, the chamber having a wall 232 providing a partition between the chamber and a tubular extension 233 disposed at a right angle to the passage through the valve. The wall 232 is provided with an opening 234 adapted to permit solvent to be diverted and flow from the main chamber 231 into the tubular extension 233 and from the valve, upon pivotal movement of a flexible seal or closure member 235 adapted to engage the peripheral edge of the opening 234 to prevent passage of solvent from the chamber into the tubular extension 233 of the valve body. More particularly, the valve closure member 235 is connected by a pin 236 to a lever arm 237 connected to a pivot pin 238 mounted in opposite facing walls of the valve body, the pivot pin having one end projecting outwardly of the valve body and being rotatable by a lever arm 239 projecting upwardly therefrom and having a lost motion connection to leverarm 240 by virtue of a slot 241 in arm 239 receiving a pin 242 xed to a lever arm 240 pivotally connected to the valve body by a fixed pin 243 between the opposite ends of the lever 240. A pin 244 is secured to the lever arm 240 and one end of a coil spring 245 is connected to the pin 244 with its other end positioned on a pin 246 fixed to a U-shaped frame 247 secured to the top of the valve body and to the tank top 153. The spring 245 normally causes the

lever arm

240 and 239 to urge the pivot pin 238 and thereby the lever arm 237 to the position shown in FIGS. 14 and 15 so that the valve closure member 235 is normally eiective to prevent the passage of solvent through the opening 234 from the chamber 231 into the tubular extension 233 of the Valve body. To open the Valve 224, pin 244 of the lever 240 is connected to the plunger 248 forming a portion of the core of a solenoid 249 mounted on the frame 247 and having a winding adapted to be energized to cause the plunger -to move to the left, as viewed in FIG. 13, for rotating lever arm 240 in a clockwise direction, and through the lost motion connection 241442, rotating pivot pin 238 in a counterclockwise direction, as seen in FIG. 15, to disengage the closure member 235 from the peripheral edge of the opening 234 in the wall 232 of the valve body to permit uid to flow into and out of the tubular extension 233 of the valve body. The cornparable solenoids of the

valves

223 and 225 are identified at 250 and 251 in FIG. 11.

Referring now to FIGS. 11 and 16, it will be assumed that the tub of machine I is empty of solvent and that solvent is continuously tiowing through the rnanifold pipe 213, the standpipe 215, and

overflow pipes

214 and 216 into and through the storage tanks of the machines. As the solenoid 250 of the valve 225 is deenergized, the solvent will not iiow from the hose 221 into machine I. To permit the solvent from the manifold pipe to enter the hose and the machine, the solenoid 250 of valve 225 is lenergized to open the valve. At this time, it may' be noted that the valve 225 has one of its two 'oppositely disposed vtubular extensions plugged, and also itsfclosure member is open so that solvent entering the hose 221 ilows through the valve body and the other open tubular extension toward and into the valve 224. As the

solenoids

248 and 250 of

valves

224 and 223 are deenergized, the solvent Hows through the aligned tube-like extensions of the valves and chambers of the valves and through hose 171 into the tub of the machine.

Accordingly, from the description of the operation of the diverter valve assembly, it will be apparent that the solvent may flow from the manifold pipe to either or both of the machines, depending upon the selective opening or closure operation of the valves 225 and 22511 of their

valve assemblies

222 and 222a as desired by the operator of the dry cleaning system. After the clothes are cleaned by the solvent for a predetermined time period, and assuming machine I is only in use, the tub of machine I may be drained by closing the valve 225 and opening the valve 224 while maintaining the valve 223 closed, the solvent then drains from the tub of the machine through the hose 171, chamber of valve 223 and, as the closure member of valve 224 is now open, the solvent is diverted into and passes through its lateral tubular extension 233 into a hose 252 extending through one side of the header 159 and into the filter basket and the storage base tank, as shown in FIGS. and 11, for circulation by the pump to the filter 177.

The present dry cleaning system is adapted also to dry the clothes and, for this purpose is provided with the heater assembly 73 and fan 32, shown in FIG. 5, t0 cause the heated air to be circulated throughout the dryer for drying the cleaned clothes. During this time, cooling water may be circulated through condenser 77 to condense the Vaporized solvent, the solvent flowing down the walls of the tub and into the hose 171. At this time, the valve 225 and the valve 224 are closed and the solenoid 251 of valve 223 is energized to open its closure member, so that the condensed solvent ows through the hose 171 into the valve 223 and flows through its lateral tubular extension into a hose 253 connected to a solventwater separator 254 shown in FIG. 17. As the condensed vapor solvent .may also contain a small portion of water, it is desirable that the water be extracted from the solvent prior to return of the solvent to the fluid supply system. For this purpose, the' water and solvent mixture enters the hose 253 and passes into the.

an opening in the tubular body for disposal to a drain` while the solvent rises upwardly through a passage 260 and into a hose 263 (FIGS. 2, l0, and l1) connected to the header 159 of the tank 152 for passage of the solvent into the lint basket and thence into the storage tank 152 of the machine.

The heat exchanger on the filter discharge line provides cooling of the solvent and maintains the solvent at temperatures between F. to 85 F. for best cleaning results. It is, of course, necessary that the water-cooled heat exchanger does not exceed 70 F.

Warning indicators are embodied in the uid supply system to inform the operator in case of an undesirable temperature of the solvent or an inadequate supply of the solvent and, for this purpose, the pipe 213, adjacent to its connection to the pipe 215, is supplied with a temperature control alarm 264 (FIGS. 2 and 3) having a thermostatic switch 265 (FIG. 20) that closes, in the event the temperature should rise, for example, above F. and opens if the temperature falls below 85 F., during solvent circulation in the described closed fluid circuit, to close an electrical circuit for lighting the indicator lamps 266 in the backguard of the machine (see FIG. l) to inform the operator of this undesirable temperature condition of the solvent, upon completion of the cleaning and drying operations. In addition, the pipe 213 is provided with the previously described solvent low level alarm 267 having a switch 268 (FIG. 20) actuatable by a pressure sensing device effective to open single pole, single throw contacts of the switch when the solvent head is maintained at liften inches but, when the solvent head becomes l2 inches, causes the contacts to close to supply electrical current to the lamps 266 at the completion of the cleaning and drying operations. The solvent level :alarm switch and temperature control alarm switch are placed in parallel in an electrical circuit having a cam-controlled switch closable at the end ofthe cleaning and drying operations, so that when either warning indicator switch is closed, fa circuit is established to the indicator lamps notifying the operator of the machine or machines that the solvent temperature is incorrect, or the solvent level head is so low, that a proper cleaning of the clothing in the machines may not occur. The indicator lamps 266 are disposed in the backguard BG of the machine (FIG. l) behind red glass, above the legend DO NOT USE on the face of the backguard of the machine to clearly indicate this undesirable condition or conditions of the solvent.

Referring to FIGS. 2 and 3, another safety feature is the condenser water control arrangement for the heat exchanger 210 provided by a water pressure switch WPS (FIG. 2) which is installed in the water line or pipe WL and ahead of a thermostatically-controlled Water regulating valve l WV in the pipe, the pipe conducting cooling water to the heat exchanger. electrical control circuit shown in FIG. 20.

With reference to the thermostatic water valve TWV, this valve functions to supply proper water temperatures to the heat exchanger. The valve TWV operates from a thermostatic sensing bulb immersed in the discharge line carrying the cleaning solvent. The. valve is designed to close-at 75 F. and to be fully open at 85 F.

In this dry cleaningsystem, each-machine may be operated independently of the other machine and, for this purpose, each machine is provided with an electrical control system shown in FIG 20, and including a sequential controller or timer arrangement, for operation of The switch WPS is in an

Claims

1. IN A FABRIC-DRYING MACHINE, A CONTAINER; A BASKET ROTATABLY MOUNTED IN SAID CONTAINER; AN ELECTRIC MOTOR FOR ROTATING SAID BASKET; A FIRST ELECTRIC CIRCUIT FOR ENERGIZING SAID MOTOR; A HEATER ELEMENT IN SAID CONTAINER AND OPERABLE TO HEAT THE AIR IN SAID CONTAINER; MEANS FOR CIRCULATING THE HEATED AIR IN SAID CONTAINER TO DRY THE FABRIC IN SAID BASKET AND INCLUDING A FAN, A CLUTCH, AND ELECTROMAGNETIC MEANS ENERGIZABLE TO ACTUATE SAID CLUTCH FOR COUPLING SAID FAN TO SAID MOTOR FOR ROTATION OF SAID FAN BY SAID ELECTRIC MOTOR; A SECOND ELECTRIC CIRCUIT FOR ENERGIZING SAID ELECTROMAGNETIC MEANS, AND INCLUDING A FIRST SWITCH; A THIRD ELECTRIC CIRCUIT FOR ENERGIZING SAID HEATER ELEMENT INCLUDING A THERMOSTAT, AND A DOUBLE THROW SECOND SWITCH OPERATIVE BY SAID THERMOSTAT AT A PREDETERMINED TEMPERATURE TO INTERRUPT SAID THIRD ELECTRIC CIRCUT; A PROGRAMMING ARRANGEMENT INCLUDING AN INTEVAL CONTROL TIMER HAVING A TIMER MOTOR, A CAM BANK ADVANCED BY IMPULSES OF THE TIMER MOTOR IN A STEP-BY-STEP MANNER AND PROVIDING TIME INTERVALS OF THE TIMER, AND INTERVAL SWITCHES OPERATIVE BY SAID CAM BANK ACCORDING TO A PRESCRIBED SEQUENCE, AND FIRST AND SECOND SUBINTERVAL TIMERS EACH HAVING A TIMER MOTOR AND A CAM BANK ADVANCED BY IMPULSES THEREOF IN A STEP-BY-STEP MANNER, AND SUBINTERVAL SWITCHES OPERATIVE BY SAID SUBINTERVAL CAM BANK TO COMPLETE CIRCUITS PERIODICALLY ENERGIZING AND ADVANCING SAID INTERVAL TIMER MOTOR DURING A TIME INTERVAL OF THE INTERVAL TIMER, SAID SUBINTERVAL SWITCHES BEING CONNECTED IN CIRCUIT WITH CERTAIN OF THE INTERVAL SWITCHES TO MODIFY CIRCUITS CONTROLLED BY THE INTERVAL SWITCHES IN ACCORDANCE WITH THE OPERATION OF THE SUBINTERVAL SWITCHES, SAID PROGRAMMING ARRANGEMENT INCLUDING A FABRIC-DRYING SEQUENCE IN WHICH SAID INTERVAL TIMER MOTOR IS ENERGIZED TO OPERATE INTERVAL SWITCHES ESTABLISHING SAID FIRST, SECOND AND THIRD CIRCUITS, SAID INTERVAL TIMER THEREAFTER INTERRUPTING ITS ENERGIZING CIRCUIT FOR SAID INTERVAL TIMER MOTOR WHILE ESTABLISHING A FOURTH CIRCUIT ENERGIZING SAID FIRST SUBINTERVAL TIMER MOTOR TO PERIODICALLY ESTABLISH THE NTERVAL TIMER MOTOR-ENERGIZING CIRCUIT TO ADVANCE THE INTERVAL TIMER MOTOR DURING THE REMAINING PORTION OF THE DRYING PERIOD; A FIFTH ELECTRIC-CIRCUIT FOR ENERGIZING SAID SECOND SUBINTERVAL TIMER MOTOR AND INCLUDING SAID SECOND SWITCH OPERATIVE TO ESTABLISH SAID FIFTH CIRCUIT UPON OPERATION OF SAID THERMOSTAT TO INTERRUPT SAID THIRD ELECTRIC CIRCUIT, ENERGIZATION OF SAID SECOND SUBINTERVAL TIMER MOTOR BEING EFFECTIVE TO OPEN SAID FIRST SWITCH TO INTERRUPT SAID SECOND CIRCUIT FOR DEENERGIZING SAID ELECTROMAGNETIC MEANS AND TO ENERGIZE SAID SECOND SUBINTERVAL TIMER MOTOR TO ESTABLISH A SIXTH CIRCUIT TO ENERGIZE SAID INTERVAL TIMER MOTOR TO ADVANCE THE INTERVAL TIMER MOTOR UNTIL SAID THERMOSTAT SWITCH IS OPERATIVE, UPON THE AIR TERMPERATURE BEING BELOW SAID PREDETERMINED AIR TIMPERATURE, TO INTERRUPT SAID FIFTH CIRCUIT AND TO REESTABLISH SAID SECOND CIRCUIT, SAID SUBINTERVAL TIMER CIRCUITS BEING IN PARALLEL RELATION TO EACH OTHER, AND SAID FIRST SUBINTERVAL TIMER HAVING ITS INTERVAL LTIMER MOTOR CIRCUIT-ESTABLISHING CONTACTS OPEN DURING ENERGIZATION OF SAID SECOND SUBINTERVAL TIMER MOTOR.