US2969654A

US2969654A - Automatic ice maker

Info

Publication number: US2969654A
Application number: US749171A
Authority: US
Inventors: Harold P Harle
Original assignee: General Electric Co
Current assignee: General Electric Co
Priority date: 1958-07-17
Filing date: 1958-07-17
Publication date: 1961-01-31
Anticipated expiration: 1978-01-31

Description

Jan. 31, 1961 i H. P. HARLE 2,969,654

AUTOMATIC ICE MAKER Filed July 17, 1958 4 Sheets-Sheet 2 F'IGZ J INVENTOR. HAROLD P. HARLE HIS ATTORNEY Jan. 31, 1961 i H. p. HARLE 3 5 VAUTOMATIC ICE MAKER Filed July-17, 1958 4 Sheets-Sheet 3 FIGH' INVENTOR.

HAoLD P. HARLE BY f Hs ATTORNEY' Jan. 31, 1961 H. P. HARLE 5 AUTOMATIC ICE MAKER Filed July 17, 1958 4 Sheets-Sheet 4 INVENTOR.

HAROLD P- HARLE H I S ATTORNEY Unite States Patert O AUTOMATIC ICE MAKER Harold P: Harle, Louisville, Ky., assignor to General Electric Company, a corporation of New York Filed July 17, 1958, Ser. No. 749,171 '6 Claims. (Cl. 62---23`3)` The present invention relates to automatic ice makers and is particularly concerned with an ice maker adapted for incorporation in a household refrigerator.

completely automatic ice makers of the type suitable for use as a component of a household refrigerator and to be cooled by the same refrigerating system employed for cooling the refrigerator compartment containing the ice maker generally include ice molds or pockets capable of providing ice pieces of a size that will readily fit in a drinking glass or the like. Because of the tendency of the ice pieces to adhere to the mold walls the harvesting of these small pieces of ice has presented a problem. In some cases this problem has been solved by the application of heat to .the mold surfaces to melt the bond between these surfaces and the ice. However, the introduction of heat into the refrigerated compartment renders the refrigerating system less eicient and the wet surfaces of the ice pieces cause the individual pieces to stick or freeze together during the storage within the comparement. To avoid these disadvantages, various mecharical arrangements have been provided for moving the mold walls relative to one another in order to mechanically break the ice adhesion. In general, the known mechanical arrangements have been rather complicated and expensive and in some cases the mechanism required for mechanically breaking the ice bond has occupied considerable space which would otherwise be available within the compartment for the storage of foodstuffs and the like.

It is therefore an object of the present invention to provide an automatic ice maker which by reason of its compact and simple design is particularly adapted for incorporation in the freezer compartment of a household refrigerator.

Another object of the invention is the provision of a compact automatic ice maker including improved means formaking and mechanically harvesting ice pieces.

A further object of the invention is to provide an automatic ice maker including a fieXible or twistable freezing tray in which ice pieces are formed, and simple and effective means for fiexing or distorting the tray to release the ice pieces.

Another object of the invention is to provide an automatic ice maker including a flexible freezing tray which is tilted from a horizontal to a discharging position for harvesting of the ice, and means for automatically subjecting the tray to a series of mechanical Operations to assure release and removal of all of the ice pieces from the tray.

Further objects and advantages of the invention will become apparent as the following description proceeds and the features of novelty which characterize the invention will be pointed out with particularity in the clains annexed to and forming part of this specification.

In accordance with the present invention there is provided a flexible tray including fixed arcuate walls defining a plurality of spaced ice molds. The tray is suitably supported for tilting movement thereof between a hori- 2,969,654 Patented Jan. 31, 1961` zontal ice making position in which it is in heat exchange relationshp with a source of refrigeration and a tilted ice ejecting position in which ice pieces can be discharged from the molds into a suitable receptacle. For the purpose of breaking the bond between the ice pieces and the mold walls, means are provided for subjecting the tray including the mold walls to a series of mechanical operations including a twisting of the tray and a subsequent sharp impact or jar to release the ice pieces from the mold. A further aspect of the present invention includes an improved arrangement for introducing a charge of water into the molds when the tray is in the horizontal position which means does not interfere with the rotational movement of the tray to and from the ice ejecting position.

For a better understanding of the invention reference may be had to the accompanying drawings in which:

Fig. 1 is a vertical view, partially in section, illustrating a preferred embodiment of the ice maker of the present invention;

Fig. 2 is a sectional view taken along line 2-2 of Fig. 1;

Fig. 3 is an end view of the ice maker of Fig. l;

Fig. 4 'is a view of certain portions of the drive mechanism employed for releasing operation of the ice maker;

Figs. 5 to 10 nclusive are views of certain elements of the drive mechanism illustrating the relative positions of these elements at various stages during the ice releasing operation of the ice maker; and

Fig. 11 illustrates the essential elements of a preferred electrical control system for controlling the operation of the automatic ice maker of the present invention.

For the purpose of illustrating the present invention there is shown in Fig. 1 of the drawing a refrigerater cabinet 1, and a freezer compartment 2. The automatic ice maker of the present invention which is illustrated as being mounted adjacent the top of the freezer compartment z'comprises a freezing tray 3 pivotally supported on a support member 4 which is in heat exchange relationship with an evaporator section 5 arranged in a horizontal position within the compartment 2.

The tray 3 which is preferably formed of sheet metal includes a plurality of spaced apart ice molds or pockets 6 adapted to receive a charge of water to be frozen and having generally arcuate transverse and longitudinal contours or cross-sections to minimize binding of the ice pieces within the molds 6 or in other words to provide a mold shape from which the ice pieces can readily be discharged after breaking the ice bond. In order to provide good heat transfer between the evaporator 5 and the contents of the molds 6, the supporting member 4 includes spaced wall members 8 defining a cell or trough 9 for receiving a charge of water which when fro zen into ice withthe tray 3 in the position shown in Fig. 1 will form a bodyof ice presenting a surface conforming to the bottom contour of the freezing tray 3 including the molds 6. As this layer of ice closely conforms to the contour of the bottom surface of the tray 3 there is thereby' established a good heat transfer path for the flow of heat from the contents of the molds 6 to the evaporator 5. A channel 10 may be provided in communication with one end of the cell 9 for the purpose of introducing water into the cell beneath the tray 3.

In its normal or ice forming position, the tray 3 is disposed in a horizontal position with the molds 6 nesting in contact with .the body of ice forming a heat transfer bridge in the cell 9 between the tray 3 and the evaporator 5. In order to provide for .tilting movement of the tray to a substantially vertical plane -in which the ice pieces, once the ice bond is broken, will fall from the molds 6 into `a suitable receptacle 11 disposed within the freezer compartment 2, the tray 3 is pivotally supported along the side edge 12 thereof on the supporting member 4. For this purpose, the tray is provided with downwardly extending

flanges

14 and 15 on the opposite ends of the tray which by means of

pins

17 and 18 are supported on -brackets 19 and 20 forming part of the support member 4. By this arrangement, the tray 3 can be moved about an axis extending through pins 17 and 13 and hence generally parallel with the edge 12 of the tray to a substantially vertical position shown in Fig. 3 of the drawing in which position ice pieces will drop by gravity from the molds 6 once thebond between the iceand the mold surfaces is broken.

A motor 21 shown in dotted lines in Fig. 1 Supplies the driving force to rotate .the tray between its two operative positions, the motor 21 preferably being enclosed within suitable insulating housing 22 extending through the insulated wall 23 of the refrigerator cabinet.

In accordance with the present invention the driving connection between the motor 21 and the tray 3 is designed to complete one ice making cycle upon rotation of the drive shaft 24 through `an angle of 360. For this purpose, the drive sha ft 24, which may be connected to the motor either directly or through a suitablegear reduction, carriesan arm 25 extending radially outward from the end of the shaft 24 and having at its outer end a pin 27 which isin driving contact with a cam member 28 fixed to the tray flange 14. The cam member 28 includes a plurality of inter-connecting `slots providing cam surfaces contacted by the cam pin 27 for imparting a rotating movement of the tray from the ice making positionto the ejecting positionand back to the ice making position. in order to mechanically release the ice pieces from the molds 6, the tray is subjected to a series of mechanical Operations including flexing ,of the tray during its travel to the vertical position followed by a sharp impact or blow.

Flexing of the tray is obtained by cooperation of the drive mechanism with an adjustable stop 29 mounted on the support member 4 by means of a bracket 30 in such a position tha-t the stop 29 Will contact the tray end 32 opposite from the end carrying the cam member during upward tilting of the tray to limit further movement of this end member as the tray 3 approaches its vertical position. The drive means by continued rotation of the driven end 33 of the tray causes a twisting or distortion of the tray and accompanying flexing and distortion of the walls of the molds 6 to break the bond between the ice pieces and the mold walls.

'For the purpose of subjecting the tray 3 to a sharp impact or jar following the flexing thereo-f during its contact with the stop 29., there is provided -an energy storing means in the form of a spring 34. This springwhich is coiled about the pin 18, has one extending end 35 anchored on the depending tray flange 15. The other end 37 is designed to engage the support 4 during rotation of the tray 3 about pin 18 to `its vertical position and prior to engagement of the tray with the stop 29 so that as the tray continues to travel into contact with the stop, energy is stored in the spring 35 biasing the tray away 'from the stop 29. This energy is released to jar the tray 3 by action of the driving means in a manner which Will -be apparent from a detailed consideration of the design and operation of the cam member 28.

The normal or ice forming position for the tray 3 the cam member 28 and the cam pin 27 is shown in Figs. 2 and 4 of the drawing; In this ice making position of the tray, the lever arm 25 through the cam pin 27 -is exerting a positive downward pressure on the cam member 28 in order to hold the tray 3 including the molds 6 in firm engagement with the ice layer contained in the cell 9. Since the release of the ice blocks from the molds 6 is effected partially by the flexing of the tray,. the tray may be so supported that while i-t is in this ice making position with the motor 21 de-energized, the drive mechanism exerts a-reverse flexing of thestray or in other words a twisting of the tray end 33 relative to the tray end 32 in a direction reverse from that obtained When the tray 3, is moved into engagement with the stop 29 during discharge o-f the ice pieces thereby providing an increased total distortion or twisting action of the tray during the ejection position of the cycle.

Upon energization of the drive motor 21, the arm 25 rotates in a clockwise direction as viewed in Fig. 2. The first action of the cam pin 27 with relation to the cam memberz is to move from the holding ridge 39 into the depression *38 and thereby release the holding pressure or reverse twist on the tray 3 and break the bond between the bottom surface of the tray and the ice in the cell 9. If the tray has been subjected to a reverse twist in its ice making position, the driven end of the tray rises to a position shown in Fig. 5. Continued rotation of the arm 25 then causes the pin 27 to enter the cam slot 4@ where, by engagement with the upper surface of theslot 40, the pin exerts a `lifting action and the entire tray starts to tilt or rotate about the axis defined by the pins 17 'and 18 to the position shown in Fig. 6 of the drawing in which the tray end 32 first engages the stop 29. Continued rotation of the arm 25 effects further rotation of the driven end 35 of the tray and ;this movement of the driven end of the tray relative to the stopped end fiexes or twists the tray as shown in Fig. 7 of the drawing so as to cause most of the ice pieces to break free `of the molds 6 and drop into receptacle 11.

During movement of the tray through the position shown :in Fig. 6 to the position shown in Fig. 7 the spring end or leg 37 Contacts support member 4 to store the energy used to subject the tray to a subsequent sharp impact or jar upon a quick release of the pin 27 from the driving surface of the cam member 28 as defined by the upper surface of the slot 49. This momentary release is obtainedwhen the pin rides off of a cam shoulder 4 2 with the result that the tray 3 sn'aps back to the position shown in Fig. S due to the action of the spring 34. Toifacilitate this quick release ,a certain amount of play or backlash can -be provided in the driving means ahead of pin 27. The return travel of the tray 3 is stopped by engagementof the pin 27 with the cam surface 43 as illustrated in Fig. 8 of the drawing and this i'c-engagement of the pin 27 with the surface 43 subjec-ts the entire tray to a sudden .or sharp impact which jars any ice pieces remaining in .the molds 6 free to fall into the receptacle 11 positioned below 'and slightly to one side of the tray 3.

During further rotation of the arm 25, the cam -pin 27 rides upwardly along the surface 43 as illustrated in Fig. 8 and eventually becomes disengaged from the cam member 28 through the open ended cam slot 44. At this point the tray falls free of the driving pin 27 and the pin 27 does not again engage the cam member 28 until the arm 25 has substantially completed its single rotation and approaches the position *shown in Fig. 2 of the drawing.

For the purpose of introducing a charge of water into the molds when `the tray is in the horizontal position, there is provided a water feed arrangement including a water spout 50 and an inlet tube 59 which is connected through a solenoid valve 60 to a water supply line 61. The valve 60 may Conveniently be housed in the housing 22 along with the motor 21. The spout 59 is carried by a support member 57 pivotally Secured as indicated by the numeral 52 on the support 4 and biased by means of a spring 54 to a position in which the forward end of the spout overhangs the tray 3 When the tray is in the normal ice making position as illustrated in Fig, 2 of the drawing and is thus in the line of travel of the longitudinal tray edge 51. To move the tray downwardly past the spout, there is provided a lever arm 46 having an elongated slot 47 for receiving the pin 27 and pivotallysecured to the ,cammember 23 at a point offset from and normally above the axis of rotation of the tray as represented by the pin 17. The curved or cam surfaces 56 provided on the support 57 permit the spout to move 'away from the normal position when contacted by the tray edge 51 during movement of the tray to either of its two limiting positions by action of the lever arm 46 when the cam pin 27 contacts the outer end of the slot 47 as illustrated in Fig. of the drawing. It will be understood that except for this returning action, the lever arm 46 rid'es freely on the cam pin 27 in all other positions of the tray 3.

The cyclic operation of the ice maker is controlled by a thermostat switch 65 mounted on one end of the tray 3 in a position in which it is rcsponsive to the temperature of the tray and hence the temperature of the contents of the molds 6. This switch 65, which forms part of a control system diagrammatically illustrated in Fig. 11 for controlling the operation of both the motor 21 and the solenoid valve 60, is normally open at temperatures above freezing and closed at below freezing temperatures or in other words a temperature at which all of the water in the mold 6 has been frozen. As can be seen from Fig. ll, closing of the thermostat switch 65 completes the energization of the drive motor 21 through the normally closed switch 66 which is in series connection with the thermostat switch 65 and which is provided for opening the motor control circuit in a manner which will be subsequently described when the receptacle 11 has been filled with ice pieces.

Initial energization of the motor 21 by closing of the thermostat switch 65 results in the cycling of the ice maker through a complete cycle involving one revolution of the shaft 24. A switch cam 68 carried by the shaft 24 controls the operation of a multiple switch arrangement 69 the purposes of which are to continue the energization of the motor 21 through a complete cycle of operation of the ice maker regardless of the temperatures sensed by the thermostatic switch 65 and -at a predetermined point to energize the solenoid valve 69 in the water supply line for introducing a charge of water into the tray 3 after it is returned to its normal or horizontal ice making position following the ejection of previously formedice pieces. From a consideration of Fig. 11 it will be seen that after the cam 68 has rotated through somewhat less than 90 or after the time that the tray comes into engagement with the stop 29, and has broken the ice free, the first set of contacts 70 and 71 of switch 69 are brought into engagement by the cam 68 to close a second motor energizing circuit which will assure continued operation of the motor 21 even though the thermostat switch 65 opens after discharge of the ice pieces from the mold. Subsequently, and after tray 3 has been returned to its horizontal position, the cam 68 by means of the projection 7.?. energizes the valve 60 by contact of the switch arm 71 with the switch arm 73. The duration of encrgization of the solenoid valve 60 is timed to introduce a measured charge of water into the tray 3 or more specifically into the molds 6 and distribution of the water throughout the molds is accomplished by means of the recessed surfaces 76 in the dividers separating the various molds 6 as shown in Fig. 4. Continued rotation of the cam 68 finally opens the motor circuit controlled by the switch arms 70 and 71 when the tray 3 has returned to its normal ice making position thus completing an ice making and harvesting cycle. I

Switch 66 is adapted to be opened and thus prevent energization of the motor circuit by the thermostat switch 65 when the receptacle 11 is full of ice pieces 'or when the receptacle 11 has been removed from the refrigerator compartment. The means for Operating this switch will become more apparent from a consideration of Figs. 1 and 4 where it will be seen that this normally closed switch 66 including a switch button 75 is arranged to be opened during each ice making cycle through rotation of a crank arm 76 by the cam member 77 carried by the shaft.24. As the cam member 77 rotates the crank arm 76 is moved into engagement with the switch button 75 and at the same time a feeler arm 78 connected to the crank arm 76 is raised from a position within the receptacle 11 to an elevated position above the receptacle 11. Continued rotation of the cam member 77 permits the arm 78 to again drop back into the receptacle 11 and in contact with the fresh layer of ice pieces discharged from the tray 3 during the cycling of the ice maker. When the amount of ice in the receptacle 11 builds up to the point where the switch arm is maintained in an elevated position by the ice in the receptacle, the crank arm 76 continues to contact the switch button 75 regardless of the position of cam member 77 thus holding the switch 66 in the open position so that the motor energizing circuit including the thermostat 65 is open and remains open until a supply of ice pieces in the receptacle 11 is again depleted to the point where the feeler arm 78 can drop to position permitting the closing of the switch 66,

In order to prevent cycling of the ice maker and discharge of ice pieces from the tray whenever the container or receptacle 11 is removed from the refrigerator, there is provided an actuating member 81 pivotally supported on the housing 22 and spring biased for movement in a counterclockwse direction to a position in which it will maintain the feeler arm 78 in an elevated position whenever the receptacle 11 is removed from the refrigerated compartment. This actuating member 81 is otherwise retained in the position shown in Fig. 1 of the drawing by contact with the slide 82 carried on one edge of the receptacle 11. Thus it will be seen that when the receptacle 11 is removed from its normal ice receiving position, counterclockwise rotation of the member 81 will move the feeler arm upwardly to open the switch 66 thereby preventing energization of the motor 21. With the receptacle 11 in position within the refrigerated compartment, the actuator 81 is rendered ineffective so that the operation of the switch 66 is under control of the amount of ice in the receptacle as sensed by the feeler arm 78.

While there has been shown and described a particular embodment of the present invention, it will be obvious to those skilled in the art that various changes and modifications may be made therein without departing from the invention, and it is intended by the appended claims to cover all such changes and modifications which fall within the true spirit and scope of the invention.

What I claim as new and desire to secure by Letters Patent of the United States is: v 1. An ice maker comprising a flexible tray, means for supporting said tray for tilting movement thereof about an axs adjacent one side of said tray between a horizontal ice making position and a tilted ice ejecting position, drive means operably connected to one end of said tray for rotating said tray to said tilted position, said drive means including a drive shaft, an arm carried by said shaft, a cam pin on said arm, and a cam member connected to said tray, a stop for engaging the other end of said tray and limiting the movement of said other end during operation of said drive means to cause flexng of said tray when rotated to the tilted position, and energy storing means for biasing said tray away from said tilted position, said cam member including a cam surface permitting said energy storing means to subject said tray to a jarring action following the flexing thereof to release any ice pieces remaining in said tray.

2. An ice maker comprising a flexible tray, means for supporting said tray for tilting movement thereof about an aXis adjacent one side of said tray between a horizontal ice making position and a tilted ice ejecting position, drive means engaging one end of said tray for rotating said tray to said tilted position, a stop for engaging the other end of said tray and limiting the movement of said other end during operation of said drive aseaes t means to cause tflexing of said tray when rotated .to the tilted position, and energy s toring means for biasing said tray away from said tilted position, and means for momentarily-disengagng said drive means from said tray when said tray is in the tilted position whereby said energy storing means subjects said tray to a sharp impact to release any ice pieces remaining in said tray.

3. An ice maker comprising a flexible tray, means for supporting said tray for tilting movement thereof about one side of said tray between a horizontal ice making position and a tilted ice ejecting position, drive means engaging one end of said tray for rotating said tray to said tilted position, a stop for engaging the other end of said tray and limiting the movement of said other end during operation of said drive means to cause flexing of said tray when rotated to the tilted position, a spring operable upon movement of said tray to its tilted position to bias said tray away from said tilted position, said drive means including release and reengaging means operable when said tray is in the tilted position whereby said energy storing means in cooperation with said drive means subjects said trayto an impact upon movement of said tray away from said stop to release any ice pieces remaining in said tray.

4. An automatic ice maker comprising a rgid supporting member, a flexible tray including a plurality of spaced molds, means for supporting one edge of said tray on said supporting member for pivotal movement of said tray about an axis extending parallel to one side of said tray between a normal substantially horizontal ice forming position and a raised ice ejecting position, means for introducing a charge of water into said molds when said tray is in the horizontal position comprising aspout pivotally supported adjacent the opposite side of said tray and having spring means normally biasing its outlet end over said opposite sideedge, said spout being provided *With a cam surfaceengaged by said opposite side of said tray during movement of said tray fromcither of its positions to the other for moving saidvspout out of the path of said tray, a stop .for engaging one end of said tray when the said tray approaches the ice ejecting position for limiting the travel of said one end, a spring mounted on said trayadjacent said one end of said tray and engageable with said support for biasing said one end away from said stop, drive means connected to the other end of said tray for transferring said tray from either of said positions to the other, said drive means comprising a drive shaft having a crank arm thereon, a campin on said arm, a cam member Secured to the other end of said tray, said cam member including a first surface for biasing said other end of said tray downwardly toward said supporting member when said tray is in the ice forming position, a second surface which upon rotation of` said shaft causes said tray first to pivot to a point where said one `end is in engagement with saidstop and said tray is flexed to distortsaid molds to attleast partially release ice pieces from said molds, said second surface terminating in a shoulder, a third surface spaced from said second surface for Contacting said pin after it leavessaid shoulder, disengag ement of said pin and said second surface permitting said spring to snap said tray away from said stop to a position in which said tray is supported by said third cam surface resting on said pin thereby subjects said tray to a sharp impact to release any ice piece remaining in said molds, a tray return lever between said arni and ,i said cam member and pivotally secured to said tray at a. point normally above and offset from said axis, said lever including a closed slot for receiving sadcam pin and an end 'wall engaged by said pin when said tray engages said spout for returning said tray to its horizontal position.

5. An automatic ice maker comprising a rigid supporting member including side and end walls defining a cell having an open top, a flexible tray including a plurality of spaced molds the walls of which flex upon flexing of said tray, means for supporting said `'tray -onsaid sup porting member for pivotal movement of said tray about 'an akis ,below one' side of said tray between a substantially horizontal ice forming position in which at least the lower portion of said tray is disposed in said cell and a substantially vertical ice ejecting position, said cell being adapted to receive a charge of water to be frozen into a body of ice conforming to the bottom contour of said tray, means for introducing a charge of water into said molds when said tray is in the horizontal position comprising a spout pivotally supported adjacent the opposite side of said tray and having spring means normally biasing its outlet over said opposite side, said spout having cam surfaces engaged by said opposite edge of said tray during movement thereof from either of its positions to the other for moving said spout out of the path of said tray, a stop for engaging one end of said tray whentsaid tray approaches the ice ejecting position, a spring mounted adjacent said one end of said tray biasng said one end away from said stop, drive means connected to the other-.end of said tray for moving said tray from one of said positions to the other, said drive means comprising a motor and a drive shaft having a .crank arm thereon and means controlling the operation of said motor for rotating said arm in one direction through one revolution of said shaft, a cam pin on said arm, a cam member secured to the other end of said tray and including slots therein forming a cam path for receiving said pin and for pivoting said tray about said axis upon rotation of said drive shaft, said cam path including a cam surface engaged by said pin during rotatior of said shaft for first rotating said tray to a :point where said one end is in engagement with said stop and said tray is twisted to distort the walls of said molds and thereafter momentarily releasing the drive means thereby permitting said spring to snap said tray away from said stop.

6. An automatic ice maker comprising a rgid supporting member, a fiexible tray comprising a plurality of transversely extending spaced molds of arcuate cross section, means for supporting said tray on said supporting member for pivotal movement of said tray about an axis extending along and adjacent to one side of said tray between a substantially horizontal ice forming position ,and a substantially vertical ice ejecting position, means for introducng a charge of water into said molds when said tray is in the horizontal position comprising a spout pivotally supported adjacent a second side of said tray and having means normally biasing its outlet end .over said second side, said spout having a cam surface engaged by said second side of said tray during movement thereof from either of its limiting positions to the other for moving said spout out of the path of said tray, a stop for engaging one end of said tray during movement of said ,tray to the ice ejecting position, energy storing means operable upon movement of said tray to said ice ejecting position, drive means connected to the other end of said tray for moving said tray from either of said positions to the other, said dri've means comprising a drive shaft having an arm thereon 'and means for rotating said arm in one direction through one complete revolution of said shaft, a cam pin on said arm, a cam member Secured to the otherend of said tray and including slots therein forming a cam path for receiving said pin and imparting pivotal movement to said tray upon rotation of said drive shaft, said cam path including a first surface for biasing said other, end of said tray downwardly toward said supporting member when .said

tray is in the ice forming position, a second surface adapted upon rotation of said shaft to cause said tray first to pivot to a point where said one end is in engagement with said stop and said tray is flexed to distort said molds and at least partially release ice pieces from said molds, said second surface terminating in a shoulder, a third cam surface spaced from said second surface for Contacting said pin after it rides off said shoulder, disengagement of said pin and said second surface permitting said energy storing means to snap said tray away from said stop to a position in which said tray is supported by said third cam surface testing on said pin and thereby release any ice pieces remaining in said molds, said third surface terminating in an open-end slot adjacent the upper wall of said cam member whereby said pin becomes disengaged from said cam path upon further rotation of said shaft, a tray return lever disposed between said arm and said cam member and pivotally Secured to said tray at a point offset from said 'axis, said lever including a closed slot for receiving said cam pin and an end wall engaged by said pin after said pin becomes disengaged from said cam path for moving said tray past said spout to a point at which said pin can again enter said cam path through said open-end slot and into engagement with said first cam surface.

References Cited in the file of this patent UNITED STATES PATENTS