US3774407A - Viscous fluid timer for tray ice maker - Google Patents

Abstract

A viscous fluid timer useful for a refrigerator automatic ice maker having a magnetic member movable in the fluid at a controlled rate under the influence of gravity where its presence will attract a magnetic switch to a closed condition to initiate the ice harvesting cycle of the ice maker. Thermostatic means are controlled such that upon the occurrence of a predetermined temperature the timer operates to interrupt the travel of the movable magnetic member whereby the viscous fluid timer is sensitive to the ice making temperature of the refrigerator.

Description

United States Patent 1 1 2/1973 Linstromberg et al. 62/233 Bright [451 Nov. 27, 1973 VISCOUS FLUID TIMER FOR TRAY ICE MAKER 1 Primary Examiner-William E. Wayner Inventor: James A. Bright, Dayton, Ohio Atwmey wflham Pemgrew et [7 3] Assignee: General Motors Corporation, Detroit, Mich. [57] ABSTRACT A viscous fluid timer useful for. a refrigerator autw Filed! d 1, 1972 matic ice maker having a magnetic member movable 2 App], 3 2 7 in the fluid at a controlled rate under the influence of Y I gravity where its presence will attract a magnetic switch to a closed condition tovinitiate the ice harvest- U-S- CL; cycle of the ice maker Thermostatic means are 200/33 R, 200/41 335/280 controlled such that upon the occurrence of a prede- II-It. Cltennined temperature timer operates to interrupt Fleld of Search the travel of the movable magnetic member'whefeby the viscous fluid timer is sensitive to the ice making [56] References Cited temperature of the refrigerator.

UNITED STATES PATENTS r I 5 Claims, 8 Drawing Figures 2,966,567 12/1960 Ovshinsky 335/280 3,055,186 9/1962 Linstromberg et a1. 62/344 X I 3,714,794

Patented Nov. 27, 1973 3 Sheets-Sheet l Patented Nov. 27, 1973' 3 Sheets-Sheet 5 VISCOUS FLUID TIMER FOR"TllAif ICE" MAKER 1 This" invention relates to viscous fluid timer 'switch' assemblies, and moreparticularlyto as'witch assembly" having thermostatic meansfor operating: the timer switch under ice making temperature conditions of a refrigerator.

In-"oneform of improved automati'c icemakerdisclosed in theEym'an'Jn, et'al. U.S. Pat."No. 3,540,227,

owned bysthe'assignee of the instant invention, a hydraulic. thermostat 'switch' is disclosed havingia hydrau- .lie tube sensing-bulb extending into'a coaxialcavity'of an ice piece mold so as to beresponsiveto' th'etemperature of the (unfrozen or frozen liquid inthe pocketSotthe mold. Such an arrangement makes 'the' removal "of the molds difficultin that thesensing bulbmustbe withdrawn from the moldb'efore the mold can be removed from the icemaker to allow for the-replacement by'a mold having different sized pockets; for exarnple.

It is therefore an object'of this invention to provide asingle viscous fluid icemaker timing; mechanism which'is selectively variable" by meansof varying the" viscosity of the liquid "chargeaina diametrically posi-- tioned rotatable chamber'to control the' rate at' which a ballof magnetic material descendswithinthe chamher. A pivotal switch arm, gravity biased into'a nor p mally open position, is mountedadjacentthelower end of the chamber upon its being:- rotated :1 80 to eitherof Y itstwo vertically oriented positions: Magneticmeans inthe form of a permanent magnet is po'sitionedon the switch arm such that the presence of the ballfwill' -attract the switcharm magnetically causing the'arm" to pivot upwardly and close the switch contacts. Thermostatic-means, in the form of a snap actingi'thermostatic disc, operates-a stopbar to'interrupt thedescent of the ball to delay the cycle timeofj the ice makerato'insure proper temperature conditions are present in the freezer compartment of a refrigerator."

It is another object of thisinventionto provide a vis-' cous fluid timer forautom'ati'c ice makers which results in a minimum of testing of such devices by eliminatingadapted to be periodically rotated by drivemeans such that a diametrically positioned-chamber filled with a viscous fluid includes asteel ballmovable in the fluid in a'controll'edmanner. Initial rotating of the chamber to a vertical oriented position'allows the ball to descend under the influence of gravity at a controlled rate to actuate an adjacent-movable switch arm','gravitationally held in normally open position, byvirtue of the ball- I moving into the field of a magnetic member on'the switch arm causing upward movement of'the switch arm to a-closedcircuit position after which the housingis rotated 180 to place the ball in position to initiate a new cycle. 1

Further objects and advantages of the present invention will be apparent from the following description,

reference being: had to the accompanying drawings, 65

wherein a preferred embodiment of the present invention is clearly shown.

In the drawings:

FIG. 1 isan irregular vertical sectional view through arefrigerator embodying an" air cooled automatic freezer illustrating one form of the invention;

FIG. 2 is an enlarged fragmentary vertical sectional" view through the automatic freezer shown in FIG. 1;

FIG.- -3is=an enlarged vertical elevational view of thefront control housing of the automatic freezer;

FIG. 4 is a horizontal sectional view taken alongthe lines 4-4 of FIG. 3;

FIG. 5 is a horizontal fragmentary sectional view taken along the lines 5 -5 of" FIG. 3;

FIG. 6 is an exploded view of the viscous fluid timer portion of the automatic freezer;

FIG. 7-is a wiring diagram of the circuits associated" with the proposed viscous fluid timer switch and schematically shows the electrical circuit operatedby said devices;

FIG. 8'is a fragmentary verticalelevational viewtof thetimer with the cover removed.

Referringnow to the drawings and moreparticularly to FIG. 1, there is shown a frost-free type of household refrigerator 20- with an upper below-freezing compart ment'22'closed by an insulated door 24 and a lower above-freezing compartment 26 closed by a lower'insu lated door 28.

These compartments are surrounded by the insulated side, top, bottom and rear walls 30 and separated by-a horizontal insulated wall 32"containing an evaporator compartment 34 provided with a finned evaporator 36" having vertical fins extending from the front to the rear.

I of the compartment 34. Evaporator compartment 34isprovided with an inlet 38 at the front communicating; with the front of the below-freezing compartment22 and additional inlets, not shown, communicating with the top of the above-freezing compartment 26. At the rear, the compartment 34 connects with a shroud 40 communicating with theentrance to a centrifugalfan 42which' is driven by an electric motor 44 housed in therear wall 30 of the cabinet. A cooling arrangement for the compartment may be similar to that shown in U.S. Pat. Nos. 3,359,750, issued Dec. 26, 1967 or 3,310,597 issued Mar. 28, 1967, and which reference,- may be had for further details of construction of the refrigerator. v

The fan 42 is provided with an upwardly extending discharge duct 46 having a distributor 48 at the top which distributes the discharge of air through the below-freezing compartment 22. Evaporator 36 is main-, tained at suitable below-freezing temperatures such as 5 to l'5 F. to maintain the compartment at the temperature of 0 F. or below.

For providing special cooling for the automatic freezer, the distributor 48 is provided with laterally extending discharge duct 50 extending along the inner section of the rear and top walls. Behind liquid freezer or automatic ice rnaker 52 the laterally extending duct 50 isprovided. with wide discharge nozzles 54 which disehargecold air directly onto the top of the ice maker 52" and particularly onto the top of the mold 56.

The mold56'is provided with two rowsof pockets 58' containing four pockets in each row and has an upwardly flanged rim 60 extending around the short and long sides thereof. The mold of the ice maker isprovided with water or any other liquid to be frozen from a pressure water system or liquid under pressure to a solenoid control valve 62 which controls the flow of water through a pipe 64 extending through the insulaabove the front pockets 58 of the mold 56. The ice maker 52 is provided with a wide U-shaped frame 68 which surrounds the mold 56 and is fastened to the adjacent side walls or wall of the freezing compartment 22 by suitable screws. Below the frame 68 is a rectan:

' gular bin carrier 70 having adjacent the rear, upwardly extending pivoting projections 72 which are pivoted by the outwardly directed pivot pins 74 extending through aligned apertures in the side walls of the frame 68. The bin carrier 70 is provided with supporting ledges 76 on its inner sides for supporting the laterally extending flanges 80 of the box-shaped bin 78. The bin 78 is provided with a double flange 82 at the front to serve as a handle.

The mold 56 is suitably pivotably supported within the automatic freezer such as by integrally molded boss means at its rear portion (not shown) which is described in the above-mentioned US. Pat. No. 3,540,227 and reference should be had to this patent for details of the mold supporting and pivoting means the disclosure of which is incorporated by reference herein. The mold 56 is formed with a pinion 167 which is provided on the front end of the coaxial sleeve 169 which is rotatably mounted in the bearing 17-1 provided in the rear cover 127. This sleeve 169 has a coaxial rearward-hollow projection 173 provided with a flat upper surface which fits tightly within a boss 175 located between the front pockets 58 of the mold 56.

A detailed description of the ejection system and the control system, except as modified, of the ice maker is unnecessary herein since such is now on the market and is preferably of the type disclosed in the Eyman, J r. et al. US. Pat. No. 3,540,227.

For accessibility all the mechanism and controls are located at the front of the freezer with the tray rotating and twisting mechanism disclosed in US. Pat. No. 3,540,227, being located in the housing 127 while the electric driving motor 126 and the control mechanism are mounted upon an irregular plastic upright electrical mounting plate 133 which closes the front end of the housing 127. The drive motor 126 has its final drive shaft (not shown) extending through the electrical control plate 133 and is provided with a drive pinion 139 on the opposite side which continuously meshes with a large driven gear 141. The large gear 141 has an apertured hub 191 (FIG. 4) rotatably mounted in a removable mannerv by a suitable snap retainer 192 on the inner shaft end of. hexagon collar bolt 143. The outer threaded end of bolt 143 extends through opening 144 in boss 145 on plate 133 and is fixedly secured thereto by lock not 147 and its collar 148.

The large timing gear 141 is recessed to receive and hold in position the thin brass nickel plated commutator 193 which" is shown bonded to the face of the gear 141 nearest the plate 133.As seen in FIG. 3 the commutator 193 includes a fill projection or segment 195 cooperating witha spring contact and terminal member 197 to measure the fill period by the timeperiod required for the fill projection or segment 195 to move past the upper end of the spring contact 197. The holding switch arm 221 is in electrical continuity with threaded terminal post C (FIG. about which a'pivotal timer switch arm 262 is rotated.

The large timing gear 141 also directly drives a small gear250 mounted on the inner end of shaft 252 extend- 4 ingthrough apertured bearing 254 inv plate 133 and has a gear 256on its outer end meshedwith, integral housinggear 258 for driving ball timer 260. The ball timer has apivotal timer switch arm 262 including'a magnetic slug 264 mounted ina cup shaped freeend portion 265 disposed adjacent the normally non-analagous periphery 266'of a rotatable ball timer housing 268 molded from a suitable plastic material such as acetal resin. The housing 268. ismounted on plate 133 by shaft 267 extending through apertured boss 270 for fixed reception in concentric hub 271 of the housing.

' As best seen in FIG. '6 a cover member272 is secured in thefront of housing 268 and suitably secured as by threaded tapping screws 274. A diametrical viscous fluid chamber 276 is formed in housing 268 for receiving aymagnetic member, which in the disclosed form is a steel ball 278 about one-quarter inch in diameter. The ball is movably retained in chamber 276 by stop means in the form of I-shaped stop bar 280 whose transverse foot portions 281, 282 are dimensioned for reception in transverse countersunk slots 283, 284, each having respective pairs of bores 285, 286 for seating paired coiled compression springs 288, 289-operatiye to bias stop bar 280 outwardly against the inner face of gasket 290 positioned between cover 272 and the outer face of housing 268 which with seal plate 291 operates to seal a charge of viscous fluid in chamber 276.

A switch holding plate 292, preferably of galvanized steel, is positioned in opposed notches 293, 294 by means of its arcuate legs 295, 296 so as to be offset from the principal vertical axis of chamber 276 by'an angle ofabout 30 degrees and is retained thereon by screws 275 and rectangular post 297 molded on cover 272 for reception in conforming aperture 299 in the switch holding plate 292. A motion transfer rod 300,

formed from'suitable insulating material, is supported in concentric alignment with bimetallic disc 302 for axial sliding movement within bore 304 of cover hub 306 and through aligned hold'308 in plate 292. The rod 300 is resiliently biased with its inner end contacting the outer face of gasket 290 and its outer end adjacent disc 302 and is operable to move axially inwardly under the influence of the thermostatic disc 302 as it snaps from an outward curvature to an opposite inward curvature in a manner to be explained. The disc 302 is shown supported at its periphery in concentric fashion by means of three tap screws 309, 310 and 311 threadably received in radially spaced cover posts 297, 298 and 303, respectively. I

As seen in FIGS. 3 and 4 a concentric casing member 320 encloses the ball timer housing 268 and its switch arm 262 and is affixed to the plate 133 by suitable means such as screws 322, extending through apertured securing tabs 324. An outer closure member 330 serves as a heater and terminal retainer located on the outer face of the cover 320 by securing tabs 331, 332 having screws 333, 334 extending therethrough. The closure member 330 is positioned in concentric fashion over circular opening 336 in cover 320 in which is located a timer heater in the form of resistor 338 (FIG. 3 having a resistance of about 6,800 ohms and a power rating of 2 watts at C, so as to heat the adjacent bimetal disc 302 upon the application of power line voltage at its terminals 339, 340 which causes a flow of current through the heater 338 in a manner to be explained.

As seen in FIG. 2 the weigh rod 243 isvertically slidably mounted through the aperture 249 in the bottom of the upright dividing wall 133 and projects through the bottom thereof and through a slotv245 in the front cross member 248 of the bin carrier 70. A bottom of the weigh rod 243 is provided with a C-shaped disc retainer 247 which is keyed thereto and which retains the weigh rod on the front cross member 248 of the bin carrier 70. Suitable bin control means are provided which in the disclosed form include a relatively strong bin supporting coil-spring 251 pressing against a disc 253 held against a'shoulder 255 of wall 133 whilea weaker coil spring 257 surrounds the weigh rod 243 between the disc 253 and ashoulder 259 of shaft 243 below V-notch242. As explained in the US. Pat. No. 3,540,227, whenever-the bin 78 'is removed from the carrier 70, the spring 257 will raise the weigh rod 243 and the adjacent right end of pivoted contact 225 to .open the circuit. When the bin 78 is placed in proper position on the carrier 70 the spring 257 will be pressed down until thespring contact 225 is in a horizontal position in engagement with the commutator 193 to close the circuit. A segment contact member 229, pivoted on terminal post B, includes a wedge shaped contact 233 adapted to be contacted by the adjacent end of pivotal switch contact member 225. The wedge shaped contact 233 is electrically connected to post B and allows for variations in loadingof the bin 78 as explained in the above-mentioned US. Pat. No. 3,540,227.

As seen in FIG. 3 the commutator 193 is shown positioned at the end of an ice harvest cycle wherein the commutator 193 has been cycled or rotated in a clockwise direction through one complete revolution of 360 bythe drive motor 126. In FIG. 3 the holding switch arm 221 has dropped-off the commutator 193 with the notch 269 positioned beneath the contact arm 221 resulting in a deenergization of the motor 126. As the housing gear 258 is geared so as to be driven by the motor 126 in unison with the driving of the commutator gear 141 but at twice the rotational speed the diagonal housing ball chamber 276 has been cycled or r0- tated'in a clockwise direction-through one-half of a revolutionvor through anangle of 180. Said differently, the chamber 276 is rotated 180 from its position shown in FIG. 8 with the ball 278 located at its lowermost point adjacent the magnet 2640f switch arm 262- ,to a position shown in FIG. 3 wherein the ball is located in its diametrically opposite position where it is free to move downward in vertically "oriented chamber 276 through the viscous fluid therein under the influence of gravity the full height of chamber 276 to starta new harvest cycle. In the disclosed embodiment the viscosity of the fluid, the length of the chamber 276 and the weight of the ball 278 are such that the time interval required for the ball to travel the full length of chamber ball 278 to close the timer switch between electrical terminal posts B and C as shown in FIG. 8. As the pivoted contact arm 225 is also closed to its wedge shaped contact 233,assuming an inserted empty or partially. filled bin, a circuit is completed from power lines L, through the arm 225, the timer switch 262, conductor 4 closed to the commutator 193 so as to complete the 276 is of the order of 90 minutes which is more than of casing 320, is pivoted upwardly by the force of attraction between the permanent magnet 264 and the motor circuit directly to L, as seen in the wiring diagram of FIG. 7. It is at this point that the mold begins to first twist (clockwise).

The holding switcharm 221 opens when the mold is at an angle of about 45 degrees to prevent continuation of the cycle and harvesting of the ice pieces in the event the bin 78 has been removed after the start of the barvest cycle. With the bin in place, current to the motor 126 continues to be supplied through the holding switch arm 221 which is closed by engaging the commutator 193 at all times except when notch 269 or the notch 234 are oriented with the rounded end of switch arm 221, as explained in US. Pat. No. 3,540,227.

, As seen in FIG. 7, upon the till projection 195 being rotated into contact with fill switch 197 a circuit is completed from L, to the commutator 193 to solenoid 392 of the fill valve 62 while the hold switch arm 221 is closed to terminal C to prevent interruption of the switch 395 is closed and the movable contact 396 of the refrigerator defrost timer switch 397 is closed to its off position in contact with fixed contact 398 to complete the circuit through conductors 399, 400 and 401 to energize the refrigerator compressor 402 across the power lines L and L together with the energization of refrigerator fan motor 404 through conductors 405 and When the defrost timer switch 397 operates to place its movable contact 396 in electrical contact with fixed contact 408 a circuit is completed through conductor 409, defrost heater 410 and defrost limiter switch 412 to energize the heater 410 and deenergize the compressor 402 and fan 404 causing the refrigeration unit to cycle off. To make the ball timer 260 sensitive to the run or on-cycle time of the refrigeration unit it will be noted in FIG. 7 that the thermostatic disc heater 338 is energized during both the defrost period and offcycle periods of the refrigerating unit, when the cold control'switch 394 is open, by completing the circuit from L commutator 193, spring contact 370, terminal post D, heater 338, conductor 414, conductor 400, the motor windings of compressor 402, conductor 401 and power line L As the bimetal disc 302 is designed to move or popin from an outward curvature to an inward curvature upon the occurrence of a first predeterminedtemperature condition, having a value in the disclosed form of 19 i 3 F., thereby causing axial inward movement of the transfer rod 300 in hub 306 (FIG. 6) to flex the gasket 290 inwardly against stop bar 280 which in turn is moved inwardly against the bias of springs 288 to engage ball 278 and interrupt its downward movement in chamber 276. It will be noted that the relatively small current flow through the compressor motor windings required to energize disc heater 338 during defrost is not sufficient to energize the compressor 402.

Upon the termination of the defrost period the movable contact 396 moves to fixed contact 298 reestablishing the circuit through compressor 402 and fan 404, and short circuiting the disc heater 338. Upon the refrigeration unit lowering the temperature in the freezer to a second predetennined temperature of about 9 i 3 F. in the instant embodiment the disc flexes outwardly or .pops-out to an opposite curvature causing the spring biased stop bar 280 to move outwardly against gasket 290 moving rod 300 axially to its initial outer position adjacent the center of disc 302.

It will be noted that if the refrigeration unit goes through a short off cycle period the temperature rise normally will not be sufficient to reach 19 F. and the ball 278 will not be interrupted in descent.

. When the ball 278 reaches the position shown in FIG. 8 closing the movable arm 262 between terminal posts B and to again initiate a harvest cycle whereby the timer housing 268 is rotated 180 by drive motor 126 which in the intant embodiment requires about 2.8 minutes. As it is essential that the timer switch arm 262 remain closed tofixed terminal post C for a certain length of time during 180 timer housing rotation the holding switch plate 292 is positioned as shown in dashed lines in FIG. 8 at about a 30 angle relative to the vertical center line of chamber 276. In this way when the housing 268 is rotated in a clockwise direction the lower flange 296 will be moved into the flux field of the permanent magnet 264 to insure that switch arm 262 remains in its closed upwardly pivoted position until the holding switch 221 is closed to complete the motor circuit therethrough directly to the commutator 193. r

A suitable high viscosity liquid charge 277 is employed in the chamber 276 having oil-like dampening characteristics and substantially constant viscosity over the temperature range of between -l F. to +10 F. encountered in thefreezer compartment of the refrigerator. Experimental work has indicated the silicone oils such as sold by Dow Corning under their stock number designation 210 are preferable for use in the viscous fluid timer herein described.

As seen in FIG. the inner face of the cover member 272 has a depressed area 273 formed therein having a uniform depth of about one-sixteenth inch such that the rubber, sealing gasket 290 extends thereover in its assembled portion sandwiched between the cover 272 and the housing 268. It will be appreciatedthat anyex pansion of the liquid charge 277 will be accommodated by the outward flexing of the gasket into the depressed area 273 whilealleviating leakage of the liquid charge from the chamber. In the embodiment disclosed the rubber gasket 290 has a material thickness of the order of 0.0l0 inches and a durometer index of about 40.

While the embodiment of the present invention as herein disclosed constitutes a preferred form, it is to be I claim:

- i 1. The combination with a refrigerator automatic ice maker adapted to manufacture and discharge ice piecesincluding a mold, means for supplying liquid to said mold, means for freezing the liquid in said mold, an electric drive motor, timer switch means, a control circuit connecting said timer switch means in series with 'said drive motor, said timer switch means including a rotational housing member of nonmagnetic material mounted to rotate about a horizontal axis, said rotational housing member having an enclosed diametrically extending sealed chamber for accommodating a high viscosity liquid therein, said drive motor coupled to said housing and adapted when energized to rotate the samethrough an angle of about to invert said chamber from its one vertically oriented position to its other vertically oriented position in response to the closing of said timerswitch means at the completion of each ice piece freezing period to initiate an ice piece harvest of said ice maker, a movable magnetic body in said liquid chamber, stop means positioned for movement in said liquid chamber from a first position permitting movement of said magnetic body to a second position interrupting the downward movementof said magnetic body, thermostatic means on said housing operative for moving said stop means from said first position to said second position upon a predeto be adjacent the lower end of said chamber when said chamber is oriented in either of its two vertical positions, said magnetic body movable through the high viscosity liquid under the influence of gravity from one upper end to the opposite lower end of said chamber during a predetermined ice piece forming time interval to close said timer contacts whereby said control circuit energizes said drive motor, said thermostatic means operative upon the attainment of said predeterw mined temperature rise in the refrigerator to move said stop means to said second position thereby interrupting the downward travel of said magnetic body until the refrigerator temperature is lowered below said predetermined temperature, whereby said resilient means operates to return said stop means to said first position such that said movable body is again free to descend in said chamber for subsequent magnetic actuation of said timer contacts.

2. A timer switch for use with a refrigerator automatic ice maker including a rotational housing member of non-magnetic material mounted to rotate about a horizontal axis, said rotational housing member having a diametrically located chamber therein, said chamber dimensioned in symmetrical fashion about said horizontal axis for accommodating a high viscosity liquid therein, drive means coupled to said housing and adapted to rotate the same in a vertical plane through an angle of about 180 so as to invert said chamber from itsone vertically oriented position to its opposite vertically oriented position in response to thecompletionof each freezing period to initiate an ice piece harvest cycle of the ice maker, a movable body of magnetic material in said chamber, cover means on said rotatable housing enclosing said chamber in a sealed manner having an axial bore therein, a motion transfer rod slidable in said bore, a thermostatic disc supported in concentric fashion on said cover means,

and movable in a snap-likemanner from one outward,

curvature to an opposite inward curvature upon the c currence of a predetermined temperature increase within the refrigerator, a stop bar positioned foraxial movement in said passage, resilient biasing means on said housing operative to biassaid stop bar t'o'a first position out of contact with said movable body, magneti cally actuated normally open switch means disposed adjacent a lower end ofsaid housing chamber when said chamber is oriented ineither of its two vertical positions, said movable body being displaceable through the high viscosity liquid under theinfluenceof' gravity during a predetermined time interval sufficient to allow the formation of ice pieces in the-ice maker, said mov-.

able body operative to close said magnetic switch means and energize said drive means upon reaching the lower end of said chamber, the movement of said thermostatic disc to said inward'curvature upon the attainment of said predetermined temperature rise operative by'imparting axialmovement to'said rod to a second disc to said outward curvature allows said biasing means to move said stop bar and said'rod to said first position such that said body is again free to descend in said chamber through the high viscosity liquid at a controlled rate for subsequent magnetic closing of said switch means. i

3. A timer switch for use with a refrigerator automatic ice maker including a rotational housing member of nonmagnetic material mounted to rotate about a horizontal axis, said rotational housing memberhaving a diametrically located chambertherein, said chamber from the, upper end of said chamber to its'lower end adjacent a lower end of said housing chamber when said chamber is oriented in either of its two vertical positions, said movable ball being displaceable through the high viscosity liquid under the influence of gravity from the upperend of said chamber to its lower end during a predeterminedtime interval sufficient to allow 1 theformation of ice pieces in theicemaker, said movable ball operative to close said magneticswitch means and energize said drive means upon reaching the lower end of said chamber, the movement of said thermostatic disc to said inward curvature uponthe attainment of said predetermined temperature increase operative by imparting axial movement to said rod to a second position moving said stop bar means into contact with said movable ball interrupting the downward movement thereof, saidmovable ballbeing prevented by said stop bar fromfurther-descent until the tempera ture in the refrigerator is lowered below said predeter mined temperature, whereby the return of said thermostatic disc to said outward curvatureallows said biasing means to move said stop bar-and said rod to said first position such that said body is again free to descend in said chamber through the high viscosity liquid at a condimensioned in symmetrical fashion aboutsaid-horizontal axis for accommodating a high viscosity liquid therein, drive means coupled to said housing and adapted to rotate thesame in a vertical plane through an angle of about 180 so as to invert said chamber from its one vertically oriented position to its opposite vertically oriented position in response to the completion'of a harvest cycle of the ice maker, a movable ball of magnetic material in said chamber, a cover removably affixed on said rotatable housing overlying said chamber, a diaphragm flexible gasket sandwiched between said cover and said housing so as to seal the high viscosity liquid within said chamber, a recess formed in the inner face of said cover whereby expansion of the high viscosity liquid is accommodated by flexture of said gasket into said recess, an axial bore in said cover, a motion transfer rod slidable in said bore, a thermostatic disc supported in concentric fashion on said cover and movable in a snap-like manner from one outon said housing operative to bias said stop bar to a first position out of contact with said movable ball, magnetically actuated normally open switch means disposed trolled. rate for subsequent magnetic closing of said pieces including a mold, means for supplying liquid-to said mold, means for freezing the liquid in said mold,

an electric drive motor, timer switch means, a control circuit connecting said timer switch means in series with said drive motor, said timer switch means including a rotational housing member of nonmagnetic material mounted to rotate about a horizontal axis, said rotational housing member having an enclosed diametrically extending sealed chamber for accommodating a high viscosity silicone liquid therein, said drive motor coupled to said housing and adapted when energized to rotate the same through an angle of about to invert said chamber from its one vertically oriented position to its other vertically oriented position in response to the closing of said timer switch means at the completion of each ice piece harvest of said ice maker, a movable steel ball in said liquid chamber, stop means positioned for movement in said liquid chamber from a first position permitting movement of said ball to a second position interrupting the downward movement thereof, thermostatic means on said housing operative for moving said stop means from said first position to said second position upon a predetermined temperature increase in the refrigerator, resilient means on said housing operative to bias said stop means in said first position, said timer switch means including a pivotal switch arm having a permanent magnet thereon, said switch arm gravity biased to afirst normally open position engaging stop means, a fixed contact of said timer switch located adjacent the lower end of said chamber in either of its two vertically oriented positions, said ball movable through the silicone liquid under the influence of gravity from one upper end to the opposite lower end of said chamber during a predetermined ice piece forming time interval, said ball upon reaching the lower end of said chamber being positioned to attract said permanent magnet and pivot said switch arm into electrical contact with said fixed contact whereby said con-' trol circuit energizes said drive motor, said thermostatic means operative upon the attainment ofsaid predetermined temperature rise in the refrigerator to move said stop means to said second position thereby interrupting the downward travel of said ball until the refrigerator temperature is lowered below said prede-' termined temperature whereby said resilient means operates to return said stop means to said first positon such that said ball is again free to descend in said chamber for subsequent magnetic actuation of said pivotal switch arm.

5. The combination with a refrigerator automatic ice maker adapted to manufacture and discharge ice pieces including a mold, means for supplying liquid to said mold, means for freezing the liquid in said mold,

an electric drive motor, timer switch means, a control circuit connecting said timer switch means in series with said drive motor, said timer switch means including a rotational housing member of nonmagnetic mate rial mounted to rotate about a horizontal axis, saidrotational housing member having an enclosed diametrically extending sealed chamber for accommodating a high viscosity liquid therein, said drive motor coupled to said housing andv adapted when energized to rotate other vertically qoriented position in response to the closing of timer switch means, a movable magnetic body in saidv liquid chamber, said timerswitch means having normally open contacts which close upon being magnetically actuated, said timer contacts located so as to be adjacent the lower end of said chamber when said chamber is oriented in either of its two verticalpositions, said magnetic body movable through the high viscosity liquid under the influence of gravity from one upper end to the opposite lower end of said chamber during a predetermined ice piece forming time interval to close said timer contacts whereby said control circuit energizes said drive motor to initiate an ice piece harvest of said ice maker.

g v UNITED STATES mm OFFICE e OF CORRECTION a t 3.774.407 t d November 27, 1973 It is certified thaterror appears in the above identified p atent and that said Letters Patent are hereby corrected 'asshown below:

l Column 7 line 33, intant should loe instant 1-1 Column 9, c1iaim*3 line 49, delete "a" (first occurrence) and insert therefor each freezing period to initiate an ice piece Column 10, claim 4, line 43, after "each" insert freezing period to; initiate an Column claim 4,

. Il. i.ne 6,, "positon" should be position Signed and sealed this 6th day of August- 1974. r

"'Atte sting Officer MCCOY M. GIBSON; JR. c. MARSHALL DANN Commissioner of Patents 7 PO-ww UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent N'J- 3.774.407 Dated November 27, 1973 lnventoflwwi i ht It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

- Column 7, line 33, "intant" should be instant Column 9, claim 3, line 49, delete "a" (first occurrence) and insert therefor each freezing period to initiate an ice piece Column 10, claim 4, line 43, after "each" insert freezing period to initiate an Column 11, claim 4, line 6, "positon" should be position Signediand sealed this 6th day of August 1974.

(SEAL) Attest:

MCCOY M. GIBSON, JR. c. MARSHALL DANN Attesting Officer Commissioner of Patents

Claims (5)

1. The combination with a refrigerator automatic ice maker adapted to manufacture and discharge ice pieces including a mold, means for supplying liquid to said mold, means for freezing the liquid in said mold, an electric drive motor, timer switch means, a control circuit connecting said timer switch means in series with said drive motor, said timer switch means including a rotational housing member of nonmagnetic material mounted to rotate about a horizontal axis, said rotational housing member having an enclosed diametrically extending sealed chamber for accommodating a high viscosity liquid therein, said drive motor coupled to said housing and adapted when energized to rotate the same through an angle of about 180* to invert said chamber from its one vertically oriented position to its other vertically oriented position in response to the closing of said timer switch means at the completion of each ice piece harvest of said ice maker, a movable magnetic body in said liquid chamber, stop means positioned for movement in said liquid chamber from a first position permitting movement of said magnetic body to a second position interrupting the downward movement of said magnetic body, thermostatic means on said housing operative for moving said stop means from said first position to said second position upon a predetermined temperature increase in the refrigerator, resilient means on said housing operative to bias said stop means in said first position, said timer switch means having normally open contacts which close upon being magnetically actuated, said timer contacts located so as to be adjacent the lower end of said chamber when said chamber is oriented in either of its two vertical positions, said magnetic body movable through the high viscosity liquid under the influence of gravity from one upper end to the opposite lower end of said chamber during a predetermined ice piece forming time interval to close said timer contacts whereby said control circuit energizes said drive motor, said thermostatic means opeRative upon the attainment of said predetermined temperature rise in the refrigerator to move said stop means to said second position thereby interrupting the downward travel of said magnetic body until the refrigerator temperature is lowered below said predetermined temperature, whereby said resilient means operates to return said stop means to said first position such that said movable body is again free to descend in said chamber for subsequent magnetic actuation of said timer contacts.

2. A timer switch for use with a refrigerator automatic ice maker including a rotational housing member of non-magnetic material mounted to rotate about a horizontal axis, said rotational housing member having a diametrically located chamber therein, said chamber dimensioned in symmetrical fashion about said horizontal axis for accommodating a high viscosity liquid therein, drive means coupled to said housing and adapted to rotate the same in a vertical plane through an angle of about 180* so as to invert said chamber from its one vertically oriented position to its opposite vertically oriented position in response to the completion of a harvest cycle of the ice maker, a movable body of magnetic material in said chamber, cover means on said rotatable housing enclosing said chamber in a sealed manner having an axial bore therein, a motion transfer rod slidable in said bore, a thermostatic disc supported in concentric fashion on said cover means and movable in a snap-like manner from one outward curvature to an opposite inward curvature upon the occurrence of a predetermined temperature increase within the refrigerator, a stop bar positioned for axial movement in said passage, resilient biasing means on said housing operative to bias said stop bar to a first position out of contact with said movable body, magnetically actuated normally open switch means disposed adjacent a lower end of said housing chamber when said chamber is oriented in either of its two vertical positions, said movable body being displaceable through the high viscosity liquid under the influence of gravity from the upper end of said chamber to its lower end during a predetermined time interval sufficient to allow the formation of ice pieces in the ice maker, said movable body operative to close said magnetic switch means and energize said drive means upon reaching the lower end of said chamber, the movement of said thermostatic disc to said inward curvature upon the attainment of said predetermined temperature rise operative by imparting axial movement to said rod to a second position causing said stop means to contact said movable body interrupting the downward movement thereof, said movable body being prevented by said stop bar from further descent until the temperature in the refrigerator is lowered below said predetermined temperature, whereby the return of said thermostatic disc to said outward curvature allows said biasing means to move said stop bar and said rod to said first position such that said body is again free to descend in said chamber through the high viscosity liquid at a controlled rate for subsequent magnetic closing of said switch means.

3. A timer switch for use with a refrigerator automatic ice maker including a rotational housing member of nonmagnetic material mounted to rotate about a horizontal axis, said rotational housing member having a diametrically located chamber therein, said chamber dimensioned in symmetrical fashion about said horizontal axis for accommodating a high viscosity liquid therein, drive means coupled to said housing and adapted to rotate the same in a vertical plane through an angle of about 180* so as to invert said chamber from its one vertically oriented position to its opposite vertically oriented position in response to the completion of a harvest cycle of the ice maker, a movable ball of magnetic material in said chamber, a cover removably affixed on said rotatable housing overlying said chamber, a diaphragm flexible gasket sandwiched between said cover and said housing so as to seal the high viscosity liquid within said chamber, a recess formed in the inner face of said cover whereby expansion of the high viscosity liquid is accommodated by flexture of said gasket into said recess, an axial bore in said cover, a motion transfer rod slidable in said bore, a thermostatic disc supported in concentric fashion on said cover and movable in a snap-like manner from one outward curvature to an opposite inward curvature upon the occurrence of a predetermined temperature increase within said refrigerator, a stop bar positioned for axial movement in said passage, resilient biasing means on said housing operative to bias said stop bar to a first position out of contact with said movable ball, magnetically actuated normally open switch means disposed adjacent a lower end of said housing chamber when said chamber is oriented in either of its two vertical positions, said movable ball being displaceable through the high viscosity liquid under the influence of gravity from the upper end of said chamber to its lower end during a predetermined time interval sufficient to allow the formation of ice pieces in the ice maker, said movable ball operative to close said magnetic switch means and energize said drive means upon reaching the lower end of said chamber, the movement of said thermostatic disc to said inward curvature upon the attainment of said predetermined temperature increase operative by imparting axial movement to said rod to a second position moving said stop bar means into contact with said movable ball interrupting the downward movement thereof, said movable ball being prevented by said stop bar from further descent until the temperature in the refrigerator is lowered below said predetermined temperature, whereby the return of said thermostatic disc to said outward curvature allows said biasing means to move said stop bar and said rod to said first position such that said body is again free to descend in said chamber through the high viscosity liquid at a controlled rate for subsequent magnetic closing of said switch means.

4. The combination with a refrigerator automatic ice maker adapted to manufacture and discharge ice pieces including a mold, means for supplying liquid to said mold, means for freezing the liquid in said mold, an electric drive motor, timer switch means, a control circuit connecting said timer switch means in series with said drive motor, said timer switch means including a rotational housing member of nonmagnetic material mounted to rotate about a horizontal axis, said rotational housing member having an enclosed diametrically extending sealed chamber for accommodating a high viscosity silicone liquid therein, said drive motor coupled to said housing and adapted when energized to rotate the same through an angle of about 180* to invert said chamber from its one vertically oriented position to its other vertically oriented position in response to the closing of said timer switch means at the completion of each ice piece harvest of said ice maker, a movable steel ball in said liquid chamber, stop means positioned for movement in said liquid chamber from a first position permitting movement of said ball to a second position interrupting the downward movement thereof, thermostatic means on said housing operative for moving said stop means from said first position to said second position upon a predetermined temperature increase in the refrigerator, resilient means on said housing operative to bias said stop means in said first position, said timer switch means including a pivotal switch arm having a permanent magnet thereon, said switch arm gravity biased to a first normally open position engaging stop means, a fixed contact of said timer switch located adjacent the lower end of said chamber in either of its two vertically oriented positions, said ball movable through the silicone liquid under the influence of gravity from one upper end to the opposite lower end of said chamber during a pRedetermined ice piece forming time interval, said ball upon reaching the lower end of said chamber being positioned to attract said permanent magnet and pivot said switch arm into electrical contact with said fixed contact whereby said control circuit energizes said drive motor, said thermostatic means operative upon the attainment of said predetermined temperature rise in the refrigerator to move said stop means to said second position thereby interrupting the downward travel of said ball until the refrigerator temperature is lowered below said predetermined temperature whereby said resilient means operates to return said stop means to said first positon such that said ball is again free to descend in said chamber for subsequent magnetic actuation of said pivotal switch arm.

5. The combination with a refrigerator automatic ice maker adapted to manufacture and discharge ice pieces including a mold, means for supplying liquid to said mold, means for freezing the liquid in said mold, an electric drive motor, timer switch means, a control circuit connecting said timer switch means in series with said drive motor, said timer switch means including a rotational housing member of nonmagnetic material mounted to rotate about a horizontal axis, said rotational housing member having an enclosed diametrically extending sealed chamber for accommodating a high viscosity liquid therein, said drive motor coupled to said housing and adapted when energized to rotate the same through an angle of about 180* to invert said chamber from its one vertically oriented position to its other vertically oriented position in response to the closing of said timer switch means, a movable magnetic body in said liquid chamber, said timer switch means having normally open contacts which close upon being magnetically actuated, said timer contacts located so as to be adjacent the lower end of said chamber when said chamber is oriented in either of its two vertical positions, said magnetic body movable through the high viscosity liquid under the influence of gravity from one upper end to the opposite lower end of said chamber during a predetermined ice piece forming time interval to close said timer contacts whereby said control circuit energizes said drive motor to initiate an ice piece harvest of said ice maker.

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