US2784563A

US2784563A - Ice making apparatus

Info

Publication number: US2784563A
Application number: US278928A
Authority: US
Inventors: Marshall W Baker
Original assignee: Motors Liquidation Co
Current assignee: Motors Liquidation Co
Priority date: 1952-03-27
Filing date: 1952-03-27
Publication date: 1957-03-12
Anticipated expiration: 1974-03-12

Description

March 12, 1957 M. w. BAKER ICE MAKING APPARATUS Filed March 27, 1952 4 Sheets-Sheet l IN VEN TOR.

BY Mamba/l M Baker March 12, 1957 w, BAKER 2,784,563

ICE MAKING APPARATUS Filed March 27, 1952 4 Sheets-Sheet 2 INVENTOR. allars/m/l W. Baker B Fig. 3 x W144 ,M%M.

March 12, 1957 M. w. B H-5R 2,784,563

ICE MAKING APPARATUS Filed March 27, 1952 4 Sheets-Sheet 5 a 34 Q Fig.5

so as 2 3 Fig. 6. l7

3:; 2 26 23 INVENTOR. Marsha/l W Baker 0 62a BY March 12, 1957 Filed Mar ch 27, 1952 M. W. BAKER ICE MAKING APPARATUS 4 sheets sheet 4 /2 Fig IN V EN TOR.

Marsho/l W Baker United States Patent ICE MAKING APPARATUS Marshall W. Baker, Dayton, Ohio, assignor to General Motors Corporation, Dayton, Ohio, a corporation of Delaware Application March 27, 1952, Serial No. 278,928 12 Claims. c1. 62-7)- The present invention relates to a refrigerating apparatus and particularly to an ice cube maker.

An object of my invention is to provide improvements in automatic, self-contained, compact ice cube making and storage apparatus to insure efficient operation thereof in the production of clear, sanitary ice cubes.

Another object of my invention is to reduce to a minimum the interval of time between an ice releasing operation and an ice forming operation in an ice cube making apparatus of the type which produces solid ice cubes of a size to be placed in glasses containing drinks to be chilled.

Another object of my invention is to provide an improved freezing member for an ice cube making apparatus wherein the low temperature employed to freeze a layer or slab of ice thereon is concentrated and substantially retarded from being transmitted to other elements in the apparatus.

Another object of my invention is to provide a water distributor for directing a film of water over a freezing member in an ice cube making apparatus which can be readily disassembled and removed from the apparatus .for thoroughly cleaning the same,

Further objects and advantages of the present inven- 2 tion will be apparent from the following description, reference being had to the accompanying drawings, wherein a preferred form of the present invention is clearly shown.

in the drawings: 7

Figure 1 is a perspective view of an ice cube maker cabinet having portions thereof broken away to show various elements in the cabinet;

Figure 2 is an enlarged front view of the ice maker cabinet shown in Figure 1 partly in section and partly in elevation;

Figure 3 is a top view of the ice cube maker on a reduced scale with the top cover thereof removed;

Figure 4 is an enlarged fragmentary vertical sectional view taken on the line 4-4 of Figure 3 showing a part of the ice thickness control for the ice cube maker;

Figure 5 is a view of the under side of the freezing member in the ice cube maker and is taken on the line 5-5 of Figure 2;

Figure 6 is an enlarged sectional view taken on the line 6-6 of Figure 5 showing refrigerant passages in the freezing member;

Figure 7 is an enlarged fragmentary sectional view of a water distributing member in the ice cube maker and is taken on the line 7-7 of Figure 2;

- element 47 disposed thereabove.

"ice

Figure 8 is a bracketed view of the water distributing member disassembled from the cabinet and showing end plugs removed from the header thereof;

Figure 9 is a diagrammatic view of various elements of the ice cube maker and shows an electrical circuit therefor;

Figure 10 is a front perspective view of a modified form of ice cube maker;

Figure 11 is a fragmentary vertical sectional view of the modified ice cube maker and is taken on the line 11-11 of Figure 10; and

Figure 12 is a fragmentary vertical sectional view taken on the line 1212 of Figure ll showing an arrangement of harvesting ice cubes from the modified ice cube maker disclosed in Figure 10.

Referring to the drawings, for illustrating my improvements, I have shown in Figure 1 thereof an ice cube making apparatus including a cabinet comprising a bottom insulated wall 11, a back insulated wall 12, upright insulated

walls

13, 14 and 15, a horizontal insulated wall 16, an insulated front wall 17 and an insulated removable cover or top wall 18 forming a compartment 20 within the cabinet. Compartment 20 is horizontally elongated at its upper portion with respect to its lower portion and therefore extends over a noninsulated machine compartment 21 provided in the cabinet. The insulated cabinet walls are of usual or conventional structure wherein the insulating material thereof is disposed between an outer metal shell or panels and an inner metal liner for the compartment 20. An inclined unitary freezing member, generally represented by the reference character 23, is stationarily mounted, preferably at an angle of approximately 15, in the upper portion of the insulated compartment 20 above the machine compartment 21. The freezing member 23 includes a plate portion comprising two superimposed and brazed together plates 26 and 27 (see Figure 6) the lower of which is embossed to provide refrigerant expansion or conveying passages 28 between the plates. These

plates

26 and 27 are formed of a metal of high heat conductivity such for example as brass. The marginal edges of the brazed together

plates

26 and 27 are bonded, such as by soldering the same, to the inner edge portions 31 of a mounting frame 32 (see Figure 6). Outer edge portions of mounting frame 32 along the two sides thereof are raised and flanged outwardly as at 33 and are bolted or otherwise suitably secured to angle iron members 34 attached to the com partment metal liner (see Figures 5 and 6). Mounting frame 32 is preferably formed of a material of relatively low heat conductivity such for example as stainless steel or a suitable insulating material. By making the frame 32 of a material having lower heat conducting properties than the plate portion of member 23, better concentration of a low temperature is obtained and transmittal of this low temperature to other elements is materially reduced. A metal cover 36 is also secured to the angle iron members 34 and is spaced from the plate portion of member 23. Cover 36 is provided with an opening 37 (see Figures 2, 3 and 4) which receives a part of a thermostatic means. This thermostatic means comprises a substantially U-shaped in cross-section arm 41 having its one end pivotally secured to a bracket 42, welded upon cover 36, by a pin or the like 43 (see Figure 4). The other end of arm 41 carries a feeler receptacle 44 containing a coiled tube 46 and a coiled electrical heating Heating element 47 is a one-half to five watt capacity electric heater. An adjustable lock screw arrangement, of any suitable or desirable construct-ion, is located between the ends of arm 41 for regulating the distance between the feeler receptacle 44 and the flat face of plate portion of freezing member 23. For example receptacle 44 may be adjusted to produce a slab of ice of from %-inch thickness to %-inch thickness. Tube 46 has its end at the coiled portion thereof sealed and has its other end connected to an expansible and contractable element 49 located in a suitable or conventional electric snap switch 50 (see Figure 9). The coiled heating element 47 has wire connections with a low voltage electric circuit to be hereinafter described.

Freezing member 23 forms a part of a closed refrigerating system and the refrigerant expansion or evaporating passages 28 between the

plates

26 and 27 of this member has a plurality of conduit connections with a refrigerant translating device. The refrigerant translating device of the refrigerating system is mounted within machine compartment 21 and comprises a motor-compressor unit 51 connected by conduit 52 with a condenser -53 (see Figure 9), which may be cooled in any suitable or conventional manner. Condenser 53 is connected to a receiver 54. A conduit 56 connects receiver 54 with the passage 28 in plate member 23. A thermostatic expansion valve 57 interposed in conduit 56 has a thermal bulb 58 and tube 59 connected thereto for operating the same as is conventional in the art. The outlet of passage 28 in member 23 is connected, by a conduit 61, to the intake side of the compressor of motor-compressor unit 51. Another conduit 62 is connected with the passage 28 in plate member 23 and this conduit extends from the top of receiver 54. A solenoid actuated valve 63 is interposed in conduit 62 and normally closes this conduit to prevent its communication with the freezing member 23 during refrigeration thereof. By referring to Figure of the drawings it will be noted that conduit 62 is secured to and extends around four sides of member 23 as at 62a for a purpose to be hereinafter described. It should also be noted that conduit 56 is secured to conduit 62a, as at 56a, along the top and bottom sides of member 23 so as to provide a head exchanger for refrigerant therein prior to its flow to and past valve 57 particularly during a freezing cycle.

Means is provided for flowing a film of water over the freezing member 23. This means comprises a header in the form of a tube 66 having a plurality of aligned small holes or orifices 67 therein along its length (see Figures 7 and 8). The metal tube or header 66 also has openings therein which fit over a pair of upstanding hollow feeder studs 68 welded or otherwise suitably secured to the frame 32 of member 23, and attached thereto by screws or the like 69. The open ends of tube 66 are closed by rubber or the like plugs 71. These plugs 71 are pressed into the-ends of tube 66 and the upright side walls of frame 32 of member 23 from a socket-like means into which the header tube 66 firmly fits. The upright side walls on frame 32 of member 23 retain the plugs 71 in place at the ends of tube 66 to seal its ends. Suitable washers may be placed between screws 69 and header 66 and between header 66 and the frame 32 to prevent leakage at these points. Studs 68 each have an opening 72 therein to permit water flowing from suitable supply pipes to circulate into the header or manifold tube 66 (see Figure 7). Water supply pipes 73 are connected to studs 68 in any suitable or conventional manner and these pipes communicate with a centrifugal water pump 76 of any suitable or desirable construction located in the bottom of a water sump receptacle 77. An electric motor 78, below receptacle 77 and outside of compartment 20, is employed to operate the water pump 76. A valve 81, actuated by a float 82, controls the flow of water through a water main 83 into the sump '77. A combined water strainer and flow meter 84 of any suitable or conventional construction is interposed in main 83 to restrict the amount of water passing to valve 81.. The strainer prevents foreign matter from entering the float valve 81 and the meter part of element 84 permits a maximum flow rate of gallons per hour with water pressure of 10 to 80 pounds per square inch. Receptacle or sump 77 is also provided with a siphon pipe 86 for a purpose to be hereinafter described. A relatively flat funnel-like memwater splash and this baffle moves about its hinged support when a slab of ice is released from the freezing member 23.

In the upper left hand portion of compartment 20 (see Figure 2) there is mounted, approximately at an angle 7% an ice dissector, cutter or grid, generally represented by the reference character 90 and which comprises a frame 91 having sets of

cross wires

92 and 93 extending in opposite directions to one another. The set of wires 92 of this ice cutting grid are disposed above the set of wires 93 and extend in a direction parallel to the direction of travel of a slab of ice to be released from member 23. The other set of grid wires 93 are located below wires 92 and extend transversely across the frame 91. Below icc cutter 90 there is a storage bin 96 (see Figure 1) for receiving ice cubes from the cutter 90. Bin 96 is closed by a horizontal swingable insulated door 97 and access to ice cubes within the bin, after opening door 97, is had by pulling out the top of a hinged inner compartment or bin door 98 (see Figures 1 and 2). Side wings provided on bin door 98 (see Figure l) prevent spilling of ice cubes from bin 96 onto the floor when door 98 is opened. A drain pipe 99 leads from the bottom of bin 96 to convey water, entering the bin from sump 77 and water from melting ice in bin 96, out of the cabinet. A thermal bulb 101 (see Figure 9) is disposed Within bin 96 at a position to be contacted by and responsive to a predetermined accumulation of ice cubes therein. A tube 102 has its one end connected to bulb 101 and has its other end connected with an expansible and contractablc element, such as a bellows, mounted in a bin thermostatic switch 103 of any desirable or conventional construction. Bulb 101, tube 102 and the bellows in switch 103 are charged with a suitable fluid and then sealed to form a temperature responsive unit for controlling the operation of ,switch 103. A switch 105 (see Figures 2 and 3), having contacts 106 and 107 (see Figure 9) one of which is mounted on a movable arm 103, is associated with the ice cutter 90. Arm 108 is disposed in the path of and is adapted to be struck and moved by a cake or slab of ice released from member 23 and slidable there-from onto the grid or cutter for a purpose to be presently described.

Electrical circuit The 115 volt power mains indicated at L and L1 lead to a low voltage, say, for example, an 11 volt transformer 116. A wire 117 leads from transformer 116 to the heater 47 .of thermostatic switch 50. A wire 118 leads from transformer 116 to contact 106 of switch 105. When

contacts

106 and 107 are closed wire 118 leads to the other side of heater 47 of switch 50. A resistance jumper wire 119 by-passes switch in wire 118 and continuously energizes heater 47 with approximately one-half watt current. This is an auxiliary feature and provides the feeler receptacle 44 of the ice thickness thermostat with a small amount of heat to at all times insure that the interior 'therof will remain dry. A branch wire 121 leads from wire 117 to wires 92 of the ice cutter 90 and a branch wire 122 leads from wire 118 to wires 93, which are connected in series with wires 92, to continuously energize the dissector or ice severing grid 90. The wires and connections just described complete the low voltage circuit incorporated in the present ice cube maker. The volt circuit includes a wire 126 branched from power main L and leading into the bin thermostat switch 103. Another wire 127 branches from power main L1 and also leads into the bin thermostat switch 103. The

wires

126 and 127 extend from switch 103 to the electric motor of the motor-compressor unit 51 to cause continuous operation of this unit, which is interrupted only by actuation of switch 103 in response to a predetermined accumulation of ice cubes within the storage bin 96. A branch wire 128 leads from wire 127, between switch 103 and unit 51, and is connected to a movable arm 129 of the ice thickness thermostat switch 50. A second branch wire 131 leads from wire 126, between switch 103 and unit 51, and is connected to a wire 132 which enters one side of a solenoid in valve 63. Wire 132 extends to the water pump motor 78. A wire 133 extends from pump motor 78 and is connected to a contact 134 of the ice thickness thermostat switch 50. The other contact 136 of switch 50 is connected by a wire 137 with the solenoid in valve 63. The contact on arm 129 of switch 50 is adapted to alternately engage or disengage the

contacts

134 and 136 in response to temperature conditions in the feeler receptacle 44 associated with the freezing member 23.

Operation Assuming that the ice cube maker is properly connected to a source of water supply, to a drain and its electrical circuit is now energized by plugging an extension cord, leading from the cabinet, into an electrical outlet. Electric current flows from the mains L and Li through switch 103 to the motor-compressor unit 51 to cause operation thereof. Simultaneously therewith electric current flows from transformer 116 through

wires

117 and 118 and

branch wires

121 and 122 to continuously energize the ice cutter 90 by directing 30 to 35 watts of current into the

resistance wires

92 and 93 to heat these wires. A small amount of current, one-half watt, flows through by-pass resistance 119 to the heating element 47 in the ice thickness feeler member or receptacle 44. At this same time electric current also flows through wire 128, arm 129, of the ice thickness thermostat switch 50, contact 134, then through wire 133 to water pump motor 7 8. The circuit is completed back to power main L from motor 78 through

wires

132, 131 and 126. Water fills receptacle 77 to a predetermined level under control of fioat valve 81. Solenoid valve 63 is closed while motor 78 operates. The pump 76 lifts water, from receptacle 77, by Way of the pipes 73, into header 66. Water is distributed in the form of a film upon the freezing plate portion of member 23 by the plurality of distributing orifices 67. The compressor of unit 51 withdraws refrigerant vapor from the passages 28 in the plate portion of freezing member 23, to cause chilling of this part of the freezing member, compresses the same and forwards the compressed refrigerant to condenser 53 Where it is cooled and liquefied in any suitable manner, such as by circulating room air over the condenser. Refrigerant liquefied in condenser 53 fiows into receiver 54 where it is further cooled and collected. Liquid refrigerant enters conduit 56 and flows through the portions 56a thereof to expansion valve 57. Liquid refrigerant is directed into the passage 28 of member 23,

by expansion valve 57, where it vaporizes, in removing heat from the plate portion of this member, and the evaporated refrigerant is returned through conduit 61, to the compressor of unit 51. The refrigerating eflect produced by member 23 causes water from the film thereof flowing over its plate portion to freeze and accumulate thereon in the form of a layer or slab of ice. When the thickness of the layer or slab of ice on member 23 reaches the feeler receptacle 44 its temperature overcomes the small amount of heat imparted, by resistor 119, to heating element 47 and cools the coiled portion of tube 46. When the temperature of tube 46 is lowered to the desired point, in accordance with a predetermined thickness of accumulation of ice on member 23 element 49 of switch 50 will contract and cause movement of switch arm 129 away from contact 134 and into engageter per hour from the receptacle.

.3 ment with contact 136. When'arm 129 disengages contact 134, of switch 50, the circuit to water pump motor 78 is broken or opened and when this arm engages contact 136 the circuit to the solenoid valve 63 is made or closed. Energization of the solenoid in valve 63 causes valve 63 to open and hot gaseous refrigerant is therefore circulated from the receiver 54 and condenser 53, through conduit 62, conduit portions 62a and thence through the passage or passages 28 in the freezer plate portion of member 23 and thereafter back to the compressor of unit 51 which continues to operate. The hot refrigerant gas first warms all four sides of freezing member 23, by flowing through conduit portions 62a, and thereafter warms inner portions thereof by its flow through passages 28. The thermostatic switch 50 therefore serves as a means responsive to a predetermined accumulation or thickness of ice on member 23 to simultaneously stop the flow of water over the freezing plate, to render the refrigerating means ineffective and torender the heating means, hot refrigerant gas line 62, effective. Heat of the gaseous refrigerant flowing around the edges of the plate portion of member 23 and through the refrigerant passages 28 therein melts and breaks the bond between the slab of ice previously formed on member 23. This released slab of ice moves otf the inclined freezing member 23 by sliding therefrom onto the inclined ice dissector or severing grid 90.

As soon as the water pump motor 78 stops operating, water flowing over the member 23 and water contained in the pipes 73 drains into the sump or receptacle 77 to raise the level of the body of water therein to a point above the uppermost portion of siphon pipe 86. This renders the siphon pipe 86 effective and substantially all of the water in the water sump is siphoned out of receptacle 77.' The siphon pipe 86 is made large enough with respect to the rate of flow of water into receptacle 77, through valve 81, and with respect to the flow of water through meter 84 that the water contained in receptacle 77 when pump 76 stops is withdrawn from the receptacle at a much greater rate of flow than that which water can enter the same. For example, when float valve 81 is opened wide, meter 84 permits only 14 gallons of water per hour to enter receptacle 77 while siphon pipe 86 is capable of removing 90 to gallons of wa- Valve 81 insures an adequate supply of Water in receptacle 77, for circulation to the water distributing header 66, under normal conditions or during a freezing cycle while siphon pipe 86 insures the drainage of substantially all water from the receptacle 77 after each freezing cycle. The draining of water from receptacle 77, after each freezing cycle, removes minerals from receptacle 77 and conveys the same down the pipe 86 to bin 96 and through drain pipe 99 to thus insure the production of pure, glistening clear ice cubes at each freezing cycle.

As the slab of ice slides onto grid 90 it strikes the movable arm 108 of switch and causes the contact 107 carried thereby to engage contact 106. Closing of

contacts

106 and 107 causes the flow of about 5 watts of electric current, around resistor 119, through

wires

117 and 118 to the heating element 47 of the ice thickness thermostat. Heat generated by the electric heating element 47 rapidly warms the coiled portion of tube 46 to thereby cause expansion of element 49 of switch 50. This provides a means of reducing the time between the removal of a slab of ice from member 23 and a subsequent ice slab freezing cycle since the arm 129 of switch 50 will be quickly moved to engage contact 134, after the slab of ice leaves the member 23. In other words the interval of time between a warming cycle and a refrigerating cycle is reduced to a minimum to insure rapid production of ice cubes. Movement of arm 129 away from contact 136 of switch 50 deenergizes the solenoid valve 63 to cause closing thereof and the engagement of arm 129 with switch contact 134 again greases energizes the water circulating pump motor 78. Heat of the one set of wires 92 in grid 90 cuts, dissects or severs the slab of icereceived thereby and resting thereon into a plurality'of long narrow slabs which fall through the space between wires 92 onto the set of wires 93. The heat of wires 93 theafter cuts, dissects or severs the plurality of long narrow slabs of ice resting thereon into a plurality of ice cubes or cubelets which fall through grid 90 intothestorage bin 96. The size of the ice cubes or cubelets is 1% inches by 1 /2 inches and of a thickness between inch and inch as determined by the adjustment of the distance between feeler receptacle 44 and the flat top of member 23. These ice cubes or cubelets can then be harvested from the cabinet by opening the insulated door 97 and bytilting the inner bin door 98 forwardly as shown in Figure 1 of the drawings. The freezing cycles and the ice releasing cycles continue until such time as the storage bin becomes substantially full of ice cubes. When ice cubes accumulate in bin 96 to the point where they will contact the bin thermostat bulb 101 the bin thermostat switch 103 is actuated to open the electric circuit leading to motor-compressor unit 51 and other elements in the 115 volt circuit of the ice cube maker. Operation of the ice cube maker will be re-established automatically after a sufiicient number of ice cubes have been removed from the storage bin thereof or have melted so as to lower the level of the ice cubes below the thermostat bulb 101.

Should the orifices 67 of water distributing header or manifold 66 become clogged with foreign matter or corroded the header 66 together with its end plugs are removed from its retaining socket means, member 23. This is done by removing the screws 69 and lifting upward on header tube 66 to slide the same, with its end plugs intact, off its upstanding feeder mounting studs 68. Thereafter the plugs 71 are removed from tube 66 to open both ends thereof (see Figure 8) whereupon a bottle or the like cleaning brush may be inserted into, passed through and reciprocated within the tube 66. Any dirt, foreign matter or corrosion in the vicinity of holes or orifices 67 will be removed and the water dis tributing member may thereafter be reassembled.

In Figures 10, 11 and 12 I show a modified arrangement for collecting and harvesting ice cubes produced in a cube maker of the type herein disclosed. In this modified showing, the ice cube maker 140 is provided with a horizontal hinged door 141 which closes an opening 142 (see Figure 11) in the front of the cabinet. Behind door 141 there is disposed two horizontally spaced apart removable trays or the like 143 (see Figure 12) mounted upon a support 144. Support 144 has openings 146 therein at the sides of trays 143. A large storage tray 147, having a front member 148 closing another opening 149 in the front of cabinet 140 (see Figure 11), is

supported upon tracks 151 located at the bottom of the storage bin. In this form of my invention ice dissected or cut into cubes by grid 90 fall into the trays 143. These trays 143 may be removed and employed as serving trays as frequently as desired to thus eliminate the necessity of a waiter or waitress scooping up the ice cubes in a serving scoop or tray. The ice trays 143 may be left in position in the cabinet and upon being filled with ice cubes additional ice cubes dropping from grid 90 will overflow the trays 143 and fall through the openings 146 in support 144. The extra or additional overflowing ice cubes drop into the tray 147 where they may be stored until a demand therefor arises. Means such as the bin thermostat switch 101 shown in Figure 9 of the drawings may be provided to prevent continued pro duction and accumulation of ice cubes in tray 147 in this modified form of apparatus if desired.

From the foregoing it should be apparent that I have provided a sanitary ice cube maker or apparatus which produces, automatically, large quantities of solid crystal clear ice cubes or cubelets. By warming the ice thickness responsive thermostat switch as soon as a slab of ice is removed from the freezing member of the apparatus I reduce the period of time between an effective freezing cycle and an ice slab removing cycle to a minimum. Also by providing the ice thickness thermostatic means with an adjustment the thickness of ice cubes or cubelets produced by the present apparatus may be varied. Since the ice cutter or dissector is continuously energized it is at all times ready to receive a slab of ice from the freezing member and effective to cut or sever the slab of ice into a plurality of ice cubelets or cubes. 7

While the form of embodiment of the invention as herein disclosed constitutes a preferred form, it is to be understood that other forms mi 'ht be adopted, as may come within the scope of the claims which follow.

What is claimed is as follows:

1. An ice making apparatus comprising, a cabinet, a plate within said cabinet, means for flowing water over said plate, means for refrigerating said plate to freeze water flowing thereover into a slab of ice thereon, means for heating said plate, said plate heating means being normally ineffective during refrigeration of said plate and while water is flowing thereover, thermostatic means responsive to a predetermined thickness of the slab of ice formed on the plate to simultaneously stop the flow of water over said plate, to render said refrigerating means ineffective and to render said heating means effective for breaking the bond between the slab of ice and the plate whereby the slab of ice slides off said plate, means within said cabinet for receiving the slab of ice slid 01f said plate and for dissecting the same into a plurality of ice blocks, means for applying heat to said thermostatic means, and means actuated solely in response to the slab of ice engaging same as it slides off said plate for controlling said heat applying means.

2. An ice making apparatus comprising, a cabinet, a plate within said cabinet, means for flowing water over said plate, means for refrigerating said plate to freeze water flowing thereover into a slab of ice thereon, means for heating said plate, said plate heating means being normally inelfective during refrigeration of said plate and while water is flowing thereover, thermostatic means responsive to a predetermined thickness of the slab of ice formed on the plate to simultaneously stop the flow of water over said plate, to render said refrigerating means ineffective and to render said heating means effective for breaking the bond between the slab of ice and the plate whereby the slab of ice slides off said plate, means within said cabinet for receiving the slab of ice slid off said plate and fordissecting the same into a plurality of ice blocks of predetermined size, means for applying heat to said thermostatic means, means actuated solely in response to the slab of ice engaging same as it slides off said plate for controlling said heat applying means, and said thermostatic means being adjustable toward and away from said plate to vary the thickness of a slab of ice to be formed thereon whereby ice blocks of a different size than said first named ice blocks can be produced by said apparatus.

3. An ice making apparatus comprising, a cabinet, a plate within said cabinet, means for flowing water over said plate, means for refrigerating said plate to freeze water flowing thereover into a slab of ice thereon, means for heating said plate, said plate heating means being normally ineffective during refrigeration of said plate and while water is flowing thereover, thermostatic means responsive to a predetermined thickness of the slab of ice formed on the plate to simultaneously stop the flow of water over said plate, to render said refrigerating means ineffective and to render said heating means effective for breaking the bond between the slab of ice and the plate whereby the slab of ice slides off said plate, means within said cabinet for receiving the slab of ice slid off said plate and for dissecting the same into a plurality of ice blocks, means continuously applying a predetermined amount of heat to said thermostatic means, and means actuated solely in response to the slab of ice engaging same as it slides off said plate for increasing the supply of heat to said thermostatic means above said predetermined amount continuously applied thereto.

4. An ice making apparatus comprising, a cabinet, a plate within said cabinet, means for flowing water over said plate, means for refrigerating saidplate to freeze water flowing thereover into a slab of ice thereon, means for heating said plate, said plate heating means being normally ineffective during refrigeration of said plate and while water is flowing thereover, thermostatic means responsive to a predetermined thickness of the slab of ice formed on the plate to simultaneously stop the flow of water over said plate, to render said refrigerating means ineffective and to render said heating means effective for breaking the bond between the slab of ice and the plate whereby the slab of ice slides off said plate, means within said cabinet for receiving the slab of ice slid off said plate and for, dissecting the same into a plurality of ice blocks of predetermined size, means continuously applying a predetermined amount of heat to said thermostatic means, means actuated solely in response to the slab of ice engaging same as it slides off said plate for increasing the supply of heat to said thermostatic means above said predetermined amount continuously applied thereto, and said thermostatic means being adjustable toward and away from said plate to vary the thickness of a slab of ice to be formed thereon whereby ice blocks of a different size than said first named ice blocks can be produced by said apparatus.

5. An ice making apparatus comprising in combination, a substantially flat plate, means for circulating water over said plate, means for refrigerating said plate to freeze water circulated thereover into a slab of ice thereon, means for heating said plate, control means maintaining said plate heating means ineffective while said refrigerating means and said water circulating means are effective, another control means substantially concurrently stopping said water circulating means, rendering said refrigerating means ineffective to cool said plate and rendering said heating means effective to break the bond between the slab of ice and said plate whereby the slab of ice slides off said plate, and means actuated solely in response to the slab of ice engaging same as it slides off the plate for causing operation of one of said control means.

6. An ice making apparatus comprising in combination, a substantially flat plate, means for circulating water over said plate, means for refrigerating said plate to freeze water circulated thereover into a slab of ice thereon, means for heating said plate, control means maintaining said plate heating means ineffective while said refrigerating means and said water circulating means are effective, another control means substantially concurrently stopping said water circulating means, rendering said refrigerating means ineffective to cool said plate and rendering said heating means effective to break the bond between the slab of ice and said plate whereby the slab of ice slides off said plate, an electric circuit for said means, a normally open switch, and means associated with said switch and engageable by the slab of ice as it slides off the plate for closing same and causing operation of one of said control means to govern the flow of electric current through said circuit to said water circulating, said heating and said refrigerating means.

7. An ice making apparatus comprising in combination, a plate having an inclined flat surface, means for circulating water over the inclined flat surface of said plate, means for refrigerating said plate surface to freeze water circulated thereover into a slab of ice thereon, control means for heating said plate, actuatable means maintaining said plate heating means inefiective while said refrigerating means and said water circulating means are effective, an-

lower end of said plate for dissecting the slab of ice slid off same, and means actuated solely in response to the slab' of ice engaging same as it slides off the plate for causing operation of one of said control means.

8. An ice making apparatus comprising in combination, a plate, means for flowing Water over said plate, means for refrigerating said plate to freeze water flowing thereover into a slab of ice thereon, means responsive to a predetermined thickness of the slab of iceformed on said plate for effecting release of the slab of ice from said plate and movement thereof from the plate, an electrically heated grid for receiving the slab of ice as it moves from said plate, said grid dissecting the slab of ice into a plurality of ice blocks and releasing the ice blocks from said grid, means for receiving and collecting the ice blocks released from said grid, means rendered effective in response to a predetermined accumulation of collected ice blocks for rendering said refrigerating means inoperative, and means for continuously energizing said grid irrespective of the effectiveness or inefiectiveness of said last named means.

9. An ice cube making apparatus including an inclined freezing plate, means for refrigerating said plate to form ice thereupon, an ice cube cutting device positioned to receive a slab of ice sliding by gravity from said freezing plate, 'a pump means for distributing water on said freezing plate, a circuit controlling said pump means, a thermostatically operable element supported above said freezing plate and designed for actuation when a slab of ice of predetermined thickness is formed on said plate, a switch means in said circuit controlled by said thermostatic element to stop said pump when an ice slab of a predetermined thickness is formed, a heating element adjoining said thermostatic element for artificially heating the same, and switch means actuated by said slab of ice and a circuit including said last named switch means and said heating element to heat the thermostatic element upon closing of said last named switch.

10. An ice cube forming device including an inclined freezing plate, an inclined ice cube cutting device positioned to receive a slab of ice sliding by gravity from said freezing plate, a pump for pumping water over said freezing plate, a thermostatic element supported above said freezing plate and actuated upon the building up of a slab of ice on said freezing plate of a predetermined thickness, 21 first switch actuated by said thermostatic element, a circuit including said first switch and said pumping unit to stop said pumping unit when said ice slab is of predetermined thickness, a heating element adjoining said thermostatic element, a switch upon said ice cutting device in the path of movement of a slab of ice moving onto the same, and a second circuit including said last named switch and said heating element and functioning to energize said heating element upon movement of the slab of ice onto said cutting device.

11. An ice making apparatus comprising, a plate, means for flowing water over said plate, means for refrigerating said plate to freeze water flowing thereover into a slab of ice thereon, means for heating said plate to break the bond between the slab of ice and the plate and to cause the slab of ice to slide off said plate, 'a thermostatic element responsive to a predetermined thickness of the slab of ice formed on the plate controlling at least one of said means, means for adjusting said thermostatic element toward and away from said plate to vary the thickness of a slab of ice formed thereon, and means hingedly supporting said thermostatic element whereby said element is free to swing away from said plate during sliding movement of a slab of ice on said plate.

12. An ice making apparatus comprising in combination,'an insulated housing, a substantially flat plate mounted in an inclined position Within the upper region of said housing, means for circulating a film ofwater downwardly across said plate, means for refrigerating said plate to freeze Water circulated thereacross into a layer of ice thereon, means for heating said plate to break the bond between the layer of ice and the plate to release the layer of ice therefrom in the form of a slab, a grid in said housing adjacent said plate for receiving the slab of ice released therefrom and for dissecting same into a plurality of ice pieces, a stonage bin below said grid within the lower region of said housing for receiving the dissected ice pieces,-

a thermostatic element associated with the side of said plate upon which the layer of ice is frozen, said thermostatic element being responsive to a predetermined thickness of the layer of ice formed on said plate for controlling at least one of said means, said thermostatic element being pivotally mounted for movement away from said side of said plate as a slab of ice is-released therefrom, and riieans for adjusting said thermostatic element relative to said side of said plate to vary the thickness of a layer of ice formed thereon whereby to change the size of ice pieces dissected by said grid.

Barrath Aug. 12, 1902 Zavarkin Oct. 29, 1918 12 Thomson Mar. 5, 1929 Taylor Dec. 8, 1936 Buchanan Oct. 25, 1938 Potter' Nov. 12, 1940 Schwimmer May 12, 1942 Langgaard June 23, 1942 Osborn Nov. 21, 1944 Jones Aug. 7, 1945 Williams Mar. 12, 1946 Pfeil May 13, 1947 Pfeil May 4, 1948 Kubaugh July 6, 1948 Crider Nov. 29, 1949 Munshower Oct. 17, 1950 Gaul Mar. 27, 1951 Leeson Apr. 17, 1951 Cobb July 24, 1951 Binder Nov. 6, 1951' Roberts Nov. 20, 1951 Pownall May 27, 1952 Drake Apr. 7, 19 53 Leeson July 21, 1953 Kattis Sept. 1, 1953 Ayres June 29, 1954 Hamlin Aug. 10, 1954 OTHER REFERENCES