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Publication numberUS3040539 A
Publication typeGrant
Publication dateJun 26, 1962
Filing dateApr 27, 1960
Priority dateApr 27, 1960
Publication numberUS 3040539 A, US 3040539A, US-A-3040539, US3040539 A, US3040539A
InventorsRichard S Gaugler
Original AssigneeGen Motors Corp
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Refrigerating apparatus
US 3040539 A
Abstract  available in
Images(2)
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Claims  available in
Description  (OCR text may contain errors)

June 26, 1962 R. s. GAUGLER 3,040,539

' REFRIGERATING APPARATUS Filed April 27, 1960 2 Shets-Sheet 1 JNVENTOR. Rib/70rd S. Gaug/er Fig.2 BYWX.%

His Attorney June 26, 1962 R. s. GAUGLER REFRIGERATING APPARATUS 2 Sheets-Sheet 2 Filed April 2'7, 1960 P type ductor semiwon N type -conducfor semi r m M m 6 m s d m (m m n '10 4 4 m His Attorney atcnt 3,sit,539 Patented June 26, 1952 3,64%,539 REFRIGERATING APPARATUS Richard S. Gaugler, Dayton, Ohio, assignor to General Motors Corporation, Detroit, Mich, a corporation of Delaware Filed Apr. 27, 1960, fier. No. 25,075 7 Claims. (Cl. 62-3) In constructing thermoelectric couples it is very important to obtain uniformity in the size of the elements and uniformity in the resistance of the elements so as to facilitate assembly of a large number of the thermocouples into a single panel in which all elements operate at maximum elficiency. A thermoelectric couple with a lower than average junction resistance, that is, a small resistance between one of the elements and the connecting bar, while operating in the panel, is not being used at its most efiicient current rating due to the larger junction resistance of the other couples. The measured differential temperature for that particular couple is then considerably less than its maximum temperature differential. On the other hand, a couple with a large junction resistance is actually operating at a higher current, in the panel, than at the current where its maximum temperature dilferential will occur. Therefore, neither the couple with the low junction resistance nor the couple with the high junction resistance, is operating at its most efiicient current. This causes a reduction in the measured temperature differential for both couples. The overall effect is that the panel willnot attain a differential as large as predicted by theory because the actual temperature differential is less than the arithmetic mean of the theoretical temperature differentials.

It is an object of this invention to provide an improved construction and arrangement of the thermoelectric units which provides for uniformity in size and which reduces the electrical resistance of each couple to a Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawings wherein preferred embodiments of the present invention are clearly shown.

in the drawings:

FIGURE l is a perspective view showing a refrigerator cabinet embodying the invention.

FIGURE 2 is a sectional view taken substantially on line 22 of FIGURE 3 with parts broken away.,

FIGURE 3 is a horizontal sectional view taken substantially on line 3-3 of FIGURE 2.

FIGURE 4 is an enlarged fragmentary elevational view with parts broken away showing the construction of the thermocouples.

Referring now to the drawings wherein a preferred form of the invention is shown, reference numeral 10 designates a refrigerator cabinet having an access opening vvlnch is adapted to be closed by means of a door 14 pivotally supported on the cabinet 10 by hinge means 16 secured to the lower edge of the door 14, a shown in FIGURE 2 of the drawings.

A first thermoelectric cooling panel assembly 20 is mounted adjacent the upper rear of the main food storage compartment 22 and a second thermoelectric cooling panel assembly, generally designated by the reference numeral 24, is arranged in the bottom wall of the food storage compartment 22 for refrigerating ice trays and the like.

Each of the cooling panel assemblies consists of a plurality of thermocouples of the type shown in FIG- URE 4, which are connected in electrical series relationship by copper straps 30. Each thermocouple consists of an n type semi-conductor element 34 and a p type semi-conductor 36. These individual semi-conductors have attached thereto mounting elements 38 which are soldered to the semi-conductor elements 34- and 36. An ultrasonic soldering gun is preferably used for this soldering operation.

By attaching the mounting elements 38 to the relatively fragile semi-conductor materials 34 and 36, it is possible to support the resulting assembly by means of the mounting elements 38 without causing injury to the semiconductor material. By virtue of the construction shown, it is possible to machine the ends of the semi-conductor subassemblies so as to make them all of'uniform length. Furthermore, the arrangement makes it possible to utilize screws 40 for securing the thermocouples to the straps 30 which connect the thermocouples in series electrical relationship. Each of the straps 30 is silver plated as shown at 32 and each of the mounting elements 38 is provided with a silver plating or coating 42 which further improves the contact between the copper straps 30 and the thermocouples.

For purposes of illustration reference has been made to use of silver coatings 32 and 42 for reducing the resistance at the point where the copper straps 39 engage the ends of the thermocouple units whereas other materials such as platinum or gold which serve as good conductors could be used in lieu of the silver. One of the reasons for using silver or the equivalent is that silver oxide is an excellent conductor and, therefore, any oxidation which might take place on the silver at the point of contact between the straps 30 and the thermocouples would not increase the electrical resistance whereas copper oxide is a very poor conductor and if the elements 38 and 30 were made of plain copper Without any silver coating, any

' slight oxide which might form on the copper would materially reduce the efficiency of the thermoelectric 'couples. For purposes of illustration the silver coatings 32 and 42 have been shown as confined to the contacting sides of the elements 30 and 38 whereas the entire elements could be silver coated or silver plated.

After the thermocouples and the copper straps have been assembled, the space between the adjacent thermocouples isfilled by means of Freon filled polyurethane foam 44 of the type disclosed in application Serial No. 809,702, filed April 29, 1959. This foam material is rigid and provides the necessary thermal and electrical insulation between the hot and cold ends of the thermocouples and firmly adheres to the surfaces of the thermocouples and adjacent metallic parts to form a very rigid panel. The Freon used in the cells of the polyurethane is preferably an insoluble retained halogenated hydrocarbon which is an excellent heat insulating medium having a coefficient of heat transfer considerably less than that of air.

panel 2d are bonded to an anodized aluminum plate 59 and the warm ends are bonded to another anodized alumia num plate 52. Y

The bonding is doneby means of an adhesive which is prepared by mixing epoxy resin with a polymeric catalyst. Other bonding mediums could be used if desired. The anodic film on the aluminum plates provides the necessary electrical insulation between the ends of the thermocouples and the plate. The resistance of the anodic film is supplemented by the resistance of the film of epoxy adhesive so that the resulting structure is electrically insulated but heat can readily pass between the thermocouples and the plates bonded to the hot and cold junctions of the thermocouples.

As best shown in FIGURE 2 of the drawings, the thermocouple assembly 20 consists of a block or unit which removably fits into an aperture 60 formed .in the back wall of the cabinet 22. Corrugated metallic fins 62 are secured to the inside plate 50 and serve to form a plurality of air flues 64 which facilitate the flow of convection air currents in thermal exchange relationship with the cold junctions of the thermocouples. The plate 52 has corrugated fins 54 secured thereto which are enclosed by means .of a channel shaped sheet metal element 66 which forms with the plate 52 a vertically extending air flue adjacent the backside of the thermocouples. A blower 68 located beneath the bottom Wall of the compartment 22 serves to forcefully circulate air in thermal exchange relationship with the hot side of the thermocouple assembly. Metallic duct means 70 serves to pull the air downwardly past the heat radiating fins 54 and into the blower inlet 72. The air is discharged through the blower outlet 74 towards the side air outlet grill 76.

The thermocouple assembly 24 located in the bottom wall of the food compartment is used for refrigerating one or more ice trays 80 and consists of an upper plate 82 on which the ice trays rest and. a lower plate84 to which heat dissipating fins 86 are secured. The fan 63 serves to pull air in over the fins 86 as well as over the fins 54.

The usual power pack 90 is mounted beneath the bottom wall of the cabinet and serves to supply direct current to the thermocouples in accordance with well known practice. Since the details of construction of the power pack form no part of the invention and since power packs of the type required are well known, the power pack needs no further description. The plates 82 and 84 are secured to the thermocouples disposed therebetween in the same manner as the plates 50 and 52- are secured to the thermocouples used in making the cooling panel assembly 20.

By virtue of the above described arrangement, it is obvious that highly efiicient thermoelectric panels are produced wherein all thermocouples have substantially equal resistance so as to provide for optimum performance at the designed current flow. Any variation in the resistance in any of the semi-conductor units or elements 34 or 36 can be compensated for by varying the length of the units or elements without varying the final overall length of the element and the mounting elements 38 attached to the ends of the elements.

While the embodiments of the present invention as herein disclosed, constitute preferred forms, it is to be understood that other forms might be adopted.

What is claimed is as follows:

1. In a thermoelectric refrigerator, a plurality of thermocouples each comprising one p and one u type semi-conductor unit, means connecting a plurality of said units in electrical series relationship to form blocks of thermocouples having hot and cold junctions on opposite sides of said blocks,'heat and electrical insulating foam material filling the voids between said units, and a pair of aluminum plates having anodic films thereon secured to opposite sides of said blocks by means of an epoxy resin adhesive, said anodic film and said epoxy resin adhesive serving to electrically but not thermally insulate said plates from said thermocouples.

2. In a thermoelectric refrigerator, a plurality of thermocouples each comprising one p and one u type semi-conductor unit, each of said semi-conductor units having a semi-conductor element secured to a pair of support members by means of solder, all of said units being silver plated, copper straps having silver plating thereon connecting a plurality of said units in electrical series relationship to form blocks of thermocouples having 'hot and cold junctions on opposite sides of said blocks, heat and electrical insulating foam material filling the voids between said units, a pair of aluminum plates having anodic films thereon secured to opposite sides of said blocks by means of an epoxy, resin adhesive, said anodic film and said epoxy resin adhesive serving to electrically but not thermally insulating said plates from said thermocouples.

3. In a thermoelectric refrigerator, a plurality of thermocouples each comprising one p and one u type semi-conductorunit, each of said semi-conductor units having a semi-conductor element secured to a pair of support members by means of solder, all of said units being of equal lengths, the ends of said units being silver plated, copper straps having silver plating thereon con necting a plurality of said units in electrical series rela tionshipto form blocks of thermocouples having hot and cold junctions on opposite sides of said blocks, heat and electrical insulating material filling the voids between said units,-and a pair of aluminum plates having anodic films thereon secured to opposite sides of said blocks by means of an epoxy resin adhesive, said anodic film and said epoxy resin adhesive serving to electrically but not thermally insulating said plates from said thermocouples.

4. In a thermoelectric refrigerator, a plurality of thermocouples each comprising one p and one n type semi-conductor unit connected in series electrical relationship, each of said semi-conductor units including a semiconductor element secured to a pair of support members by means of solder, the ends of said units being silver plated, straps of conducting material having silver plating thereon connecting a plurality of said units in electrical series relationship to form panels of thermocouples having hot and cold junctions on opposite sides of said panels.

5. In a thermoelectric refrigerator, a plurality of thermocuples eachcomprising one p and one 11 type semiconductor unit, each of said semi-conductor units including a semi-conductor element sandwiched between a pair of support members, all of said units being of equal lengths, the ends of said units being silver plated, copper straps having silver plating thereon connecting a plurality of said units in electrical series relationship to form panels of thermocouples having hot and cold junctions on opposite sides of said panels.

6. In a thermoelectric refrigerator, a plurality of thermocouples. each comprising one p and one u type semi-conductor unit, each of said semiconductor units comprising. a pair of support members and a semi-conductor element disposed in abutting relationship between said support member, all of said units being of equal length irrespective of variations in lengths of said semiconductor elements, the ends of said units being silver plated, copper straps having silver plating thereon conmeeting a plurality of said units in electrical series relationship to form blocks of thermocouples having hot and cold junctions on opposite sides of said blocks, heat and electrical insulating foam material filling the voids between said units and bonded to said units and to said connecting means to form a rigid panel.

7. In a thermoelectric device, a plurality of thermocouples each comprising one p and one u type semi conductor unit, each of said semi-conductor units comprising a pair of metallic support members and a semiconductor element sandwiched between said metallic support members, the free ends of said metallic support members being plated with a metal, the oxide of which is a good conductor of electricity, and connector means contacting said plated ends for connecting a plurality of said units in electrical series relationship to form panels of thermocouples having hot and cold junctions on opposite sides of said panels.

References Cited in the file of this patent UNITED STATES PATENTS Gaugler Ian; 29, 1957 Lindenblad i Aug. 5, 1958

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US2779066 *May 23, 1952Jan 29, 1957Gen Motors CorpInsulated refrigerator wall
US2846494 *Nov 30, 1955Aug 5, 1958Rca CorpThermoelectric devices
US2921973 *Apr 16, 1957Jan 19, 1960Westinghouse Electric CorpThermoelements and devices embodying them
US2932953 *Aug 10, 1956Apr 19, 1960Gen Electric Co LtdThermoelectric cooling units
US2932954 *Oct 17, 1958Apr 19, 1960Westinghouse Electric CorpIlluminating and heating and cooling panel member
US2942051 *Mar 11, 1958Jun 21, 1960Whirlpool CoRefrigerating apparatus
US2943452 *May 14, 1959Jul 5, 1960Westinghouse Electric CorpThermoelectric warming and cooling appliance
US2949014 *Jun 2, 1958Aug 16, 1960Whirlpool CoThermoelectric air conditioning apparatus
US2970449 *Apr 25, 1958Feb 7, 1961Whirlpool CoThermoelectric refrigerating apparatus
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3111166 *Apr 13, 1961Nov 19, 1963Gen ElectricPortable heating and cooling appliance
US3138934 *Nov 19, 1962Jun 30, 1964Kysor Industrial CorpThermoelectric heating and cooling system for vehicles
US3168816 *Dec 30, 1963Feb 9, 1965Gordon D PetrieThermoelectric refrigerator structure
US3172269 *Oct 31, 1962Mar 9, 1965Technical Operations IncThermoelectric refrigerator
US3177671 *Jun 12, 1963Apr 13, 1965Arvin Ind IncThermoelectric device
US3180100 *Sep 6, 1962Apr 27, 1965Borg WarnerThermoelectric refrigerating devices
US3214922 *Sep 14, 1964Nov 2, 1965Willi ZornSatchel
US3232063 *Jun 26, 1964Feb 1, 1966Whirlpool CoCooling plate and shelf structure
US3279955 *Jan 8, 1963Oct 18, 1966Gen Motors CorpMethod of forming electroplated thermoelectric junction and resultant article
US3306835 *Feb 4, 1965Feb 28, 1967Agatha C MagnusTreatment of substances with ultrasonic vibrations and electro-magnetic radiations
US3326726 *Mar 22, 1963Jun 20, 1967Gen Motors CorpThermoelectric array and method of manufacture
US3332807 *Jan 30, 1962Jul 25, 1967Borg WarnerThermoelectric assembly dielectric barrier comprising anodized layer and dimethyl silicone fluid
US3351498 *Mar 29, 1963Nov 7, 1967Gen ElectricSeparately cartridged thermoelectric elements and couples
US3379577 *May 1, 1964Apr 23, 1968Cambridge Thermionic CorpThermoelectric junction assembly with insulating irregular grains bonding insulatinglayer to metallic thermojunction member
US3821881 *Jul 14, 1972Jul 2, 1974Mobile Metal Prod IncRefrigerator box with door mounted refrigeration unit
US3937028 *Sep 18, 1974Feb 10, 1976Compagnie Industrielle Des Telecommunications Cit-AlcatelModule for conditioning air by the peltier effect and air conditioning installations comprising such modules
US4029520 *May 28, 1974Jun 14, 1977Minnesota Mining And Manufacturing CompanyThermoelectric generators that incorporate self-segmenting thermoelectric legs
US4326383 *Aug 4, 1980Apr 27, 1982Koolatron Industries, Ltd.Compact thermoelectric refrigerator
US4587810 *Jul 26, 1984May 13, 1986Clawson Machine Company, Inc.Thermoelectric ice maker with plastic bag mold
US4738113 *Apr 25, 1986Apr 19, 1988The Cola-Cola CompanyCombination cooler and freezer for refrigerating containers and food in outer space
US4783967 *Jun 12, 1987Nov 15, 1988Portion Control Systems, Inc.Dispenser with temperature control
US4804118 *Nov 12, 1986Feb 14, 1989Portion Control Systems, Inc.Food dispenser with timer control
US4807441 *Jul 17, 1987Feb 28, 1989Allied-Signal Inc.Cooling system for a sealed enclosure
US4917179 *Sep 14, 1989Apr 17, 1990Beckman Instruments, Inc.Gold plated copper insert surrounded by bast aluminum body
US4961320 *May 19, 1988Oct 9, 1990Klaus GutmannConveying and storage device for thermosensitive products
US5070701 *Aug 1, 1989Dec 10, 1991Matsushita Electric Industrial Co., Ltd.Cooling apparatus
US5661979 *Apr 8, 1996Sep 2, 1997Deboer; EdSelf-contained refrigeration device for fruit
US5841064 *May 27, 1996Nov 24, 1998Matsushita Electric Works, Ltd.Peltier module
US6295820Mar 14, 2000Oct 2, 2001Delta T, LlcFruit chiller
US6619045Jul 10, 2002Sep 16, 2003Delta T, LlcFood chiller with improved cold air distribution
US6625991Jul 10, 2002Sep 30, 2003Delta T, LlcSpace saving food chiller
US6651445Jul 10, 2002Nov 25, 2003Delta T, LlcFood chiller with ductless air circulation
US6658858Jul 10, 2002Dec 9, 2003Delta T, LlcFood chiller with enclosing air duct system (SE-2)
US6763665Jul 10, 2002Jul 20, 2004Delta T, LlcFood chiller with optimized air flow
US8261572 *Jul 9, 2009Sep 11, 2012Samsung Electronics Co., Ltd.Food heat-exchange device and refrigerator having the same
US20100071874 *Jul 9, 2009Mar 25, 2010Samsung Electronics Co., Ltd.Food heat-exchange device and refrigerator having the same
US20100186423 *Jan 23, 2009Jul 29, 2010Prince Castle Inc.Hot or cold food receptacle utilizing a peltier device with air flow temperature control
DE1243702B *May 7, 1963Jul 6, 1967Kurt KoblischekTragbare Kuehltasche fuer Batteriebetrieb
EP0271704A2 *Nov 6, 1987Jun 22, 1988unitechnica Mobilkälte GmbHThermo-electric cooling device
WO1988009220A1 *May 2, 1988Dec 1, 1988Beckman Instruments IncImproved thermoelectric cooling design
WO1988009907A1 *Jun 2, 1988Dec 15, 1988Portion Control Systems IncDispenser with temperature control
WO1996012920A1 *Aug 9, 1995May 2, 1996Malia Francisco Javier AcostaEcological thermoelectric refrigerating system
WO2004034480A1 *Oct 5, 2002Apr 22, 2004Geiger JohannPeltier element
Classifications
U.S. Classification62/3.6, D15/81, 136/230, 136/225, 136/204, 136/237
International ClassificationF25D11/00, F25B21/02
Cooperative ClassificationF25B2321/0251, F25D11/00, F25B21/02
European ClassificationF25B21/02