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Publication numberUS2471655 A
Publication typeGrant
Publication dateMay 31, 1949
Filing dateDec 28, 1943
Priority dateDec 28, 1943
Publication numberUS 2471655 A, US 2471655A, US-A-2471655, US2471655 A, US2471655A
InventorsRundell Theodore W
Original AssigneePhilco Corp
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Automatic ice maker
US 2471655 A
Abstract  available in
Previous page
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Claims  available in
Description  (OCR text may contain errors)

May 3l, 1949. T. w. RUNDELL l 2,473,555 v AUTOMATIC ICE MAKER Filed Dec. 28, 1943 5 SheetsSheet l nllllm ay 3l, 1949. T. w. RUNDELL l 2471v655 AUTOMATIC ICE MAKER Filed Dec. 28., 1943 5 Sheets-Sheet 2 May 3l, 1949c 3 Sheets-Sheet 3 Filed Dec. 28, 1943 Patented May 31, 1949 I sTATEs PATENT ori-ICE AUTOMATIC ICE MAKER Theodore W. Rundell, Abington, Pa., assignor, by mesne assignments, to Philco Corporation, Philadelphia, Pa., a corporation of Pennsylvania Application December 28, 1943, Serial No. 515,958

UNITED This invention relates to refrigeration, and

has especial reference to a method and apparatus for th'e automatic production of ice masses.

More particularly, the invention is concerned with a method of and apparatus for the automatic and sequential freezing of ice masses for same in readily available form.

In domestic-refrigerators now in general use, it is common to provide a freezing chamber withv in which separate ice trays are inserted, each lled with water to be frozen into masses commonly called cubes. After the cubes have been formed, it is necessary to remove the tray from the refrigerator, and to free the cubes from the tray by the use of warm water, or some like expedient. Following this, the tray must be refilled and returned to the refrigerator for a re-initiation of the freezing cycle.

Such a process is not `only time-consuming and inconvenient, but in addition, is disadvantageous as all of the ice cubes must be freed from a container, even though the user may require only a small number thereof. Moreover, ice obtained in this way cannot readily be stored for future use, since the film of water present upon the freed cubescauses them vto freeze together upon replacement within the freezing chamber. Still further, the ice tray is generally tightly bonded to the supporting surface of the freezing compartment and, as a consequence,

l s claims. (ci. (sz- 2) domestic consumption, and the storing of the dispensing said masses, one by one, Without wastage of the remaining masses and without ren quiring removal of the latter from the freezing compartment.

The invention also contemplates the provision of an ice making apparatus in which ice production is automatically discontinued when the storage capacity of the unit has been reached.

A further object relates to a novel method of and apparatus for producing freely accessibleice cubes, for storage as set forth, said method and requires the use of levers or other special devices to effect removal thereof. These and other difficulties have recently given rise to a very considerable commercial demand for refrigerators capable of automatic and continuous formation of ice. and of maintaining the ice in such a condition. that it may be removed piece by piece, as and when required.

It is, therefore, a primary object of the present invention to overcome the aforesaid dimculties by the provision of a method of and apparatus for the automatic freezing, freeing, and storing ofv a readily accessible supply of ice.

More particularly, it is. an object of the invention to provide an apparatus in which ice forming `molds are automatically supplied withwater to be frozen, and in which thermo-sensitive 'means is-provide'dfor freeing the frozen masses from the mold member, after the completion of the freezing cycle.

Still more particularly, the present invention has as an object, the provision of ice making apparatus having a bi-metallic member for freeingthe frozen masses from the mold, and for apparatus functioning .in continuous cycle until the storage container is fully loaded.

A more specific object of the invention is to y provide means for breaking the bond between-the ice masses and the mold members, by use of a -bimetallic thermo-sensitive disk arranged asone wall portion of the mold member.

The invention further contemplates the prol vision of apparatus of the general -type setforth1 which is exceedingly compact and enables location of the operating components and supply system exteriorly of the freezing. chamber.

It is also an object toprovide an apparatus of thetype set forth, which embodies novel means for preventing'premature freezingof the water to be delivered to the ice molding members. 'I'hese and other objects and advantages will be best understood by a consideration of the following description in conjunction. with the accompanying drawings, in which:

Fig. 1 is a perspective view of a'refrigerator embodying the invention, portions being broken away for the sake of clarity in illustration;

Fig. 2 is an enlarged sectional view of a portion of the apparatus illustrated in Fig. 1;

Fig. 3 is a sectional view taken on line 33 of Fig. 2;

Fig. 4 is anenlarged sectional View of the ice molding member and certain associated apparatus;

Fig. 5 is a fragmentary perspective view, illustrating certain details of the mold member;

Fig. 6 is a view in perspective of the loi-metallic Fig. '7 is a perspective view of one of the ice masses produced in accordance with the present invention, and

Fig. 8 is a perspective view illustrating one feature of the invention.

With particular reference to Fig. 1 of the drawings. the reference character 2 designates, generally, a domestic refrigerator of the mechanical type including an outer shell 3, which may be of any well known type and construction. and an inner metal shell or liner member 4 which forms the walls of the food storage space indicated at 5, said space preferably being tted with suitable shelves (not shown). Vertical and horizontal breaker strips 6 and 1, respectively, of low thermal conductivity, are fitted around the forward marginal edge of the cabinet opening; while thermal insulation, indicated at 8, completely surrounds the inner liner member. that the cabinet is provided with a door adapted to seat in the plane of the breaker strips 6 and 'I, said door having been omitted from the drawing for the sake of clarity in illustration. As revealed by the broken-away portions of the cabinet shells,

there is a machinery compartment 9 located beneath the food storage space, which compartment houses the compressor unit indicated at I0. A horizontal floor member I I divides the machinery compartment from the upper portions of the cabinet, the insulation 8 being continued thereacross. As the particular refrigerant flow circuit employed to effect cooling of the food storage space forms no part of the present invention, such flow passages and the connections thereto have not been illustrated in the drawings.

In the embodiment illustrated, a double thickness partition I2 provides a floor for the food storage compartment (this partition preferably being of the type known commercially by the trade name Thermopane) and a gasket I3, best seen in Fig.. 2, -is interposed between the partition -members and the adjacent wall portions of the inner liner 4. Mounted beneath this partition is a lowtemperature evaporator designated generally by the reference character I4, which comprises a horizontal floor I5, vertical side walls I6 and a central vertical wall I1, dividing the space within said evaporator into a pair of compartments maintained at freezing temperatures. As shown in Fig. 2./ the evaporator is provided with an outwardly turned flange portion I8 at the free edge of each of the vertical walls I6, by means of which the evaporator is supported in the cabinet by connections eiected at I9 in the general plane of the partition member I2.

In accordance with the invention, and as rst briefly described in connection with Figs. 1, 2 and 3, the novel apparatus of the present invention comprises a plurality of ice molding members or cups 20 formed in the lower wall of the evaporator I 4, to which cups water is fed from a storage tank 2l located within the food storage compartment 5, the level of the water in the cups being determined and maintained by some suitable float valve mechanism indicated generally by the cylindrical housing 22. The operating cycle, as will be fully described hereinafter, includes lling of the cups 20 to the desired level, freezing of the contents thereof, and subsequent extrusion or forcing out of the ice masses from the cups by means of a temperature responsive element. This upward movement automatically conditions the mechanism to permit the iniiow of additional water to fill the space left It will be understood' by the raising of the 'ice block, after which the freezing cycle is re-initiated. Walls 23 and 23a extend upwardly from the floor of the'evaporator,

. said walls running from the forward to the rearv ward edge of the evaporator in general parallelism with the side walls I5 and closely adjacent to the cups 20. A pair of cover. members 24-24 are slidingly supported in the evaporator side wall and the partitions 23 and 23a define an enclosed space around the cups 20. 'I o obtain access to the frozen ice masses, the cover members may be drawn forwardly (see Fig. 8), suitable handles 24a being provided for .the purpose.

Describing the ice forming and storing apparatus with more particularity, and with special reference to Figs. 2 to 6 inclusive, it will appear that water is delivered from the storage tank 2l (maintained at a temperature above freezing) to a downwardly extending pipe 25, and into the aforesaid float chamber 22. While areservoir has been illustrated and described which is adapted to be placed within the food storage area, it will be clear that the inlet line 25 of the -water supply feed apparatus could be directly connected with the house' water supply, if such is. desired. From the float chamber, as best seen in Fig. 3, a passage 26 delivers the water to a supply header 21, -whichis arranged centrally beneath the cupped portion of the evaporator I4 to supply water to all the cups, by means of upwardly extending short connections 28. Each of these connection passages 28 passes upwardly through a vertically arranged hollow conduit 29, the lower end of which passes through the floor I I and is in open communication with the motor-compressor` com partment.

The purpose of these'conduits is to conduct suicient heat from the compressor upwardly to the region of the tubing 28, to insure that freezing will not occur in said tubes, that is, below the level of the lower wall of the cups 20. In addition, and to further insure delivery of warm water to the cups 20 (for a purposewhich will appear later) the supply header 21 is located closely adjacent to the top wall II of the machine compartment.

Making reference to Fig. 4, the members 2li are each surrounded by a space 30, which is a part of the refrigerant evaporator circuit and provides for rapid freezing of the Water delivered to the cups. In order to maintain a more constant temperature in the vicinity of the cups 20, the refrigerant ow passages 30 are preferably arranged so as to constitute a portion of the refrigerant inlet supply header.Y Although the refrigerant will be, at least to some extent, active in this zone, this arrangement will maintain the passages 30 in a substantially ooded condition, thereby serving to maintain a more constant temperature throughout the operating cycle.

Although any convenient form of evaporator circuit may be employed, there has been illustrated an evaporator of the type having a balanced central feed to the bottom wall thereof (through passage 3I appearing in Fig. 2) afterl which the refrigerant passes upwardly through parallel connections 32 to the exhaust headers 33, one of which is illustrated in Fig. 3.

Still with reference to Fig. 4,- it will be 'seen' that the cups 20 are of generally frustro-conical configuration and are provided with a lower lcylindrical part 34. Within this cylindrical-por- `larged ow passages g l, cent portions 38 of the evaporator', as by means of Welding. A centrally bored plug member 39 has threaded engagement with the inside surface of the sleeve 35 and the water supply pipe 28 is mounted within said plug and is secured as by means of the weld indicated at 40. Plug 39 f has a lower annular extension 4l of reduced size, to which is secured the upper end of conduit 29. A gasket is shown at42, being interposed between plug 39 and the flanged portion of sleeve 35; vand a threaded collar 43 serves to maintain l the desired gasket pressure. Y Y

As illustratedin Figs. 4 to 6, inclusive, a bimetal thermo-sensitive disk 44 is positioned in the lower portion of each of the cups 29, plug member 39 being shaped to provide a seat for the disk when said disk is in the position shown in full lines. This disk is movable with a snapaction between the upper and lower positions shown in Fig. 4 in dotted and full lines, respectively. The upper portion of sleeve 35 is formed so as to overlie the adjacent edges of the bi-metal disk, as shown at d5, in order tomaintain the disk in the proper position and to provide a reaction point for its over-center toggle action. The bi-metal element carries a valve member 46'flxed to the lower surface thereof, which is adapted to cooperate `with a valve vseat 41 to control the passage of water through the delivery system. It will be understood that this valve is carried upwardly when the disk mo'ves to the position shown l in dotted lines.

As best seen in Fig. 5, each of the disks has a number of apertures 48, through which water l is delivered to the cup as will be described.' Plug member 39 is fitted with upstanding projections 49 for registry with the aperturesV 48 when the disk moves to its lower position. These projections serve to close the openings 48 when the disk is in its lower position, in order to prevent formation of ice in the disk apertures. As may be seen from a comparison of Figs. and 6, the cup 29 has a projection 50- which is adapted to cooperate with a slot 5| formed in the edge of the bi-metal disk. Cooperation between the elements 50 and 5| prevents rotation of the disk within its seat 45, which rotative movement would deexample in the neighborhood of from 0 to 15 F. The existence of this predetermined minimum temperature operates to raise the thermo-sensitive disk to its upper position (shown in dotted lines) thereby opening the valve i6 and the ports 48. Water now flows from the supply tank 2l and is delivered to the cups through pipes .25

and 28, as described, under regulation lby the float valve device 22 and as indicated at 5B in Fig. 4.

The water thus introduced to the cupsl will be warm as compared to the temperature of said cup and of the disk 44, byvirtue of the heat exchange taking place through the conduit 29, and also due to the fact that the water -supply-header' 21 is located immediately above the machine compartment. When the cup has been completely lled with relatively warm water, to the level indicated at 56 in Fig. 4, the temperature of the bi-metaldisk 44 will be raised sufliciently to cause it to snap back to its lower position shown in fulllines, thereby closing the valve 46 against its` seat 41, and plugging the disk flow ports 48 to prevent formation of ice therein. It will be understood that bi-metal disks are not new inthe fart, per se, but that the characteristics of the disk must be predetermined so as to cause it to snap between its upper and lower positionsin stroy` the desired registry between the water flow apertures 48vand the projections 49. Y

In assembling the cup structure, the bi-metal disk is first snapped into position beneath the overhanging portions of the sleeve 35,' and the plug 39 threaded into said sleeve, after which the resultant'assembly is tt'ed within the flange portion 34 of the cup. Application of the pipes 28 andI 29 and the 'collar 43 completes the assembly.

'It shouldbe noted that a ring 52, of rubber y or the like, -surrounds the top of each of the cups 20 and is provided with an annular lip 53 extending somewhat into the cup opening, said lip having a number of slots formed thereabout. This ring is maintained in position by an apertured plate 54, provided with downwardly turned portions adapted to engagev the ring. As shown in Fig. 2, the plate 54 is secured to the fixed A evaporator structure.

4 The operation of the device is as follows:

Let it be considered first that the evaporator i4 is operating. and that nolwater has as yet been delivered to the cups 20; in such4 circumvalve device.

response -to the differential temperatures existingt during `theoperating cycle. The-disk is further of a type which is capable of exerting an upward force sufficient to break the bond existing between the ice iock and the mold member, and'to raise said block upwardly a distance equal to the complete travel of said disk.

Due to the action of the evaporator portions 39, the liquid contained in the cup 20 is then frozen, during which time the disk remains in its lower position until completion of Vthe freezing operation.l This maintenance of the lower disk position is readily accomplished, by virtue of the fact that at the freezing point heat abstracted by the evap- -orator is primarily effecting a change of state in v positionfreeing the bond between the ice and the mold andextruding or forcing the ice block'upwardly until it projects out of the cup. The reference numeral 51 appearing in Fig. 4,l indicates a dot and dash representation of the position of the i-ce block after it has been raised. Asthe ice block is raised, the resilient lip portion 53 is forcedl backwardly out of the cup opening under the infiu'ence' of the rising block and thereafter returns to the position illustrated, in which it Will maintain the mass of ice in its raised position, without the support of disk member 44.

At this period in the operating cycle, water will again flow into the cup 20 in the manner described above, completely filling the space between the raised block of ice and the sidewalls of the cup, to the level determined by the float The slots 53a are provided in the lip edge, in order to insure proper operation of the level-determining device, by maintaining the area immediately above the water in the cups at atlrnospheric pressure throughout the operating stance the evaporator circuit, lincluding the en- 30, willlower the temperature of the cups 20.'. and therefore the disks 44 to some predetermined minimum temperature, for

cvcle. From this point on the cycle is repeated. with the thermo-sensitive disk snapping to its lower position and the freezing of the water being reinitiated. The cyclic operation of the mechanism will continue until a cylinder of `.ice is formed in each cup, which projects upwardly a distance suflcient to make contact with the horizontally extending shelf 24, shown in Fig. 2. An

l removed (in which connection see Fig. 8) by sliding said shelf forwardly out of contact with the upper portions of the cylinders of ice, the above described cycle will recommence, thereby freeing the ice block from the cup and permitting the ready removal thereof. It will be understood, of

course, that the cover member 24 is drawn for- Wardly .only a sufficient distance to expose and free the number of ice cubes desired, the balance of said cubes remaining in contact with the under surface of the cover. When the ice has been removed from any cup and the shelf is repositioned, an accumulation of ice is again built up in said cup to the leVel of the shelf.

From the foregoing description, it will be seen that the invention provides a completely automatic apparatus for the sequential production of ice, said apparatus further serving-to store the ice in readily available form, and accessible position. The proportions of the ice blocks may be varied, as desired, but said blocks are preferably of such a size that one thereof is adequate for use with the ordinary tumbler. Further, it will be seen that the invention is capable of automatic automatic termination of the process by virtue of a restraining force created by the dimensional increase of said ice mass.

2. A method for the cyclic production of ice,

which comprises supplying water to an icemold ing receptacle, freezing said water to form an ice mass, freeing the mass from the mold member automatically in response to the temperature of the mass and effecting positive movement of the mass toward a barrierand partially out of the mold member, effecting additional inflow of water to be frozen, freezing said additional water While in contact with the previously frozen mass to effect a bond therewith, effecting controlled cyclic repetition of the aforesaid steps until said mass Amakes contact with the barrier, and utilizing the restraining force so created to effect automatic termination of the process.

3. Apparatus for forming and dispensing ice masses, said apparatus comprising a mold member adapted to receive water to be frozen into ice; means for sequentially and cyclically supplying water to said moldv member freezing said water, and at least partially extruding the ice thus formed from the mold member, said means including a thermo-sensitive element operative upon the completion of each freezing cycle to effect said extrusion of the ice and to reinitiate the Water supply.

production and dispensing of ice, without wastage of any of the ice produced, and without necessitating the removal of any ice from the freezing compartment except as and when needed.A

In the method aspect, the invention includes the novel concept involved in cyclically effecting: automatic and controlled water supply, followed by formation of ice and movement thereof to a free and accessible position, concurrently effecting additional iniiow of Water to be frozen and termination of the process when the storage capacity has been reached, by virtue of a restraining force created by the dimensional increase of the ice block itself. y

While a preferred structural embodiment of the invention has been illustrated, it Should be understood that the details thereof are merely illustrative, and that the invention contemplates such changes and modifications as may come within the scope of the annexed claims. The terms extrusion and "extruding herein are used in the broad sense of thoseterms to mean to thrust, force, press or push out.

I claim:

LA method for the cyclic production of ice, which comprises supplying water to an ice-molding receptacle, freezing said Water to form an ice mass, freeing the mass from the mold member automatically in response to the temperature of l the mass and effecting positive movement of said mass to a position in which at least a portion thereof is displaced from the freezing zone of said receptacle, supplying additional Water to the` molding receptacle, freezing said additional Water Vin contact with the mass previously frozen to eifect a bond therewith, effecting controlled cyclic repetition of the aforesaid steps until a mass of a desired size has been formed, and then effectingv 4. In apparatus for forming and dispensing ice masses, a, mold member adapted to receive water to `be frozen, means for freezingthe water to form an ice mass, a bimetallic thermo-sensitive element adapted to free said mass from the mold member and to effect movement thereof to an accessible position at the completion of the freezing cycle, and means for maintaining the mass in such position.

5. In ice forming apparatus, a refrigerated mold; means for supplying Water to the mold for conversion into ice; temperature responsive means at the bottom of the mold movable under differing temperature conditions between an extended position, wherein said means projects into the ice freezing area of the mold cavity, and a retracted position withdrawn from said area; and a valve controlling the said water supply and operatively associated with the temperature responsive means so as to provide for admission of water to the mold when the said means is extended and for exclusion of the water when the said means is retracted.

6. In ice forming apparatus, a refrigerated mold, means for supplying water to the mold for conversion into ice, a valve controlling said supply, and a temperature responsive device constituting a means for automatically displacing the ice in the mold after the entire water content of the mold has been frozen and for simultaneously actuating the valve to admit additional water to the mold, said device beingv operative under the influence of the relatively elevated temperature of the admitted water to return the valve to water excluding position.

7. In apparatus for the formation of ice by continuous cyclic operation, a refrigerated mold, means for supplying water to the mold for conversion into ice, avalve controlling said supply, a thermo-sensitive device in thermal association with the mold constituting a means for automatically displacingthe ice in said mold to afford space for additional water and for simultaneously actuating the valve to admit said water, said device being actuated to effect said displacement by relatively low temperatures occurring in vposition under the influence of relatively low temperatures occurring when rthe entire water content` of the mold is frozen, said means in the extended position projecting into the waterfreezing area of the mold cavity sovas to displace the body of ice in themold, said thermo-sensitive means being associated with the valve and operative when moving'l to said'extended position to effect opening of the valve for admission of additional water to the mold, and said ther-mo-y sensitive means being movable to a retracted DO sition withdrawn from said area oi' themoldcav- A 10 i ity under the influence of relatively' elevated temperatures occurring .as a result of said water admission and being operative in said retractive movement to eiect return o1' the valve to a closed position excluding water from the mold.


REFERENCES CITED The following references are of record in the ille of this patent:

UNITED STATES PATENTS Number Name Date 191,256 Riker May 29, 1877 1,788,393 Hull Jan. 13, 1931 2,026,227 .Foraker Dec. 31, 1935 2,077,820 Arp Apr. 20, 1937 2,145,773 Muiily Jan. 31, 1939 2,259,966 Gaston Oct. 14,` 1941A 2,296,327 .Barish Sept; 22, 194:2` lf2-,359,780

u Oct.. 10. 19a-1 Y

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Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2639594 *Aug 10, 1949May 26, 1953Watt John RFreezing machine
US2683359 *Aug 25, 1950Jul 13, 1954Francis Wm TaylorIce-making method and apparatus
US2747379 *Apr 9, 1952May 29, 1956Flakice CorpLaminae freezer
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U.S. Classification62/71, 62/353, 236/48.00R, 62/135, 62/356, 62/337, 236/93.00R, 62/75
International ClassificationF25C1/04
Cooperative ClassificationF25C1/04
European ClassificationF25C1/04