US2850883A

US2850883A - Refrigerating apparatus

Info

Publication number: US2850883A
Application number: US502791A
Authority: US
Inventors: Lawrence A Philipp
Original assignee: American Motors Corp
Current assignee: American Motors Corp
Priority date: 1955-04-21
Filing date: 1955-04-21
Publication date: 1958-09-09
Anticipated expiration: 1975-09-09

Description

Sept 9, 1958 l.. A. PHlLlPP 2,850,883

REFRIGERATING APPARATUS Filed April 21, 1955 2 Sheets-Sheet 1 Sept. 9, 1958 L. A. PHILIPP 2,850,883 f REFRIGERATING APPARATUS Filed April 21, 1955 2 sheets-sheet 2 I'J. l "'z Y 359;??? f- 66 'II'INIIIIII'I'IIIIIIL INVENTOR. dh/E//K' Fla /PP 1T l n ,mbsf i states @tt REFRIGERATENG APPARATUS Lawrence A. Philipp, Detroit, Mich., assigner to American Motors Corporation, Detroit, Mich., a corporation of Maryland Application Apri-1121, 1s ss, serai No. 502,791

1 cnam. (crm- 1an The present invention pertains to refrigerating apparatus and more particularly to a cooling of the compressor and condenser used in such apparatus.

One of the objects of my invention is to provide an improved arrangement for dissipating the heat of condensation from a refrigerant condensing element.

Another object of my invention is to provide an improved arrangement for controlling the flow of air over a refrigerant motor-compressor unit and refrigerant condenser assembly.

It is another object of the present invention to provide a condenser having suciently large surface area to provide for the effective cooling and condensing of the refrigerant vapors by the natural flow of air` thereover and being so arranged that only a portion of the cooling air will ow therefrom to provide cooling of a motor compressor unit.

It isanother object of the present invention to provide a condenser arranged in two sections havinga combined surface cooling area for effective cooling and condensing refrigerant vapor by natural ow of air thereacross and when the ambient temperature attains a predetermined high value to provide a forced circulation of cooling air over one section of the condenser to effect full cooling and .condensing of the refrigerant therein requiring little or no cooling as the refrigeranty is conducted through the other section of the condenser.

It is another object of the present invention to provide a motor operated fan for forced circulation of airV across a motor-compressor unit and a portion of a condenser whereby the fan is thermostatically controlled to operate only when the ambient temperature attains a predetermined high value.

Further objects and advantages of the present invention 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.

ln the drawings:

Fig. 1 is a front view of a refrigerator embodying features of my invention and showing a portion thereof broken away;

Fig. 2 is a side View of the refrigerator showing a portion thereof broken away;

Fig. 3 is a view in cross section taken along line 3-3 of Fig. l

Fig. 4 is a view in cross section taken along line 4-4 of Fig. l;

Fig. 5 is a diagrammatic illustration of the refrigeration system embodying features of my invention; and

Fig. 6 is a diagrammatic illustration of the controls in a wiring diagram embodying features of my invention.

Referring to the drawing, the numeral 20 designates in general a refrigerator cabinet having a food storage compartment 22 and a machine compartment 24. The food storage compartment 22 is adapted for the storage of frozen foods, ice cream and the like, and is formed within an inner sheet metal liner 26 supported in :spaced relation Qto an outer sheet metal casing or wrapper 2S of the cabinet 20. VInsulation 29 is interposed between the liner 26 and the casing 28. The food storage compartment has an opening at the topthrough which access-to the interior of the compartment may be had, and which opening is closed .by suitable lids or closure members 30.

The cabinet 20 rests upon and is secured to a supporting frame 32 which comprises

rails

34, 36 and 37. The

rails

34 and 36 extend parallelto a front wall 38 and rear Wall 40 of the outer sheet metal .casing 28 of the cabinet. The rail 37 extends parallel to end wall 42 of the casing 28 to join one end of

rails

34 and 36 whose opposite ends are not connected to provide access opening 44 to a space or passageway 46 formed within the frame 32 between the bottom of the cabinet and oor. The space or passageway 46 is in open communication with the machine compartment 24 whose walls include end wall 42, front wall 38, rear wall 40 of the outer casing 28 and a sheet metal partitional wall 50. Access to the machine compartment 24 is provided by opening 52 formed in front wall 38 of the casing. A guard grill or screen 54 is placed across the opening52.

To refrigerate the food storage compartment 22 there is provided a refrigerating system designated in general by the numeral 60, comprising a hermetically sealed motorcompressor unit 62, a condenser 64 consisting of two

sections

66 and 68, refrigerant evaporating coils 70 serpentined about and bonded in thermal heat exchange relation to the exterior surface of the inner sheet metal liner 26, and an accumulator 72.

The motor-compressor unit 62 is secured on frame 74 which rests upon supporting guide rails 76. The frame is slideable on the rails 76 to facilitate the placement of the unit 62 into the machine compartment, or for its removal from the machine compartment. The rails 76 extend between the supporting

frames rails

34 and 36 and are secured thereto. Also supported on the frame 74 by a bracket 78 is a motor 80 having a shaft` 82 upon which is secured a fan 84.

The .condenser plate section k66of the condenser-64 is adapted to be positioned within thespace 46 land includes refrigerant conduit'90 serpentined about and secured to a surface of a sheet metal lplate 92 which plateprovides a iinned surface. The sheet metal .plate 92 is suspended and secured in spaced parallel relation tothe bottom wall of the cabinet `20.by brackets 96. The conduit may be thermally bonded to the plate .92 by weld, straps, or by any vother well known means. The condenser section '68L is a continuation Vof the condenser section 66 and includes refrigerant conduit 98 Vserpentined to extend about the inner surface ofthe'front and rear walls ofthe outer sheet metal .casing 28. The conduit 9S is bonded in thermal heat exchange relation with the casing 2S. Y Y

Tov control tand Vregulate Vthelfoperationfor the ymotorcompressor unit 62 there is provided a thermostatic control which is responsive to the temperature of the food storage compartment 22. A second thermostatic control 112 is provided to control and regulate the operation of the fan 84. The thermostatic control 112 includes a switch mechanism 114 and a thermo-sensitive power element 116 positioned to be in close proximity to the shell of the motor-compressor unit 62. The switch mechanism and power element of the thermostatic control 112 are supported within and protected by a metallic shield 118 which is secured by leg 117 to the frame 74. The shield is formed with a front opening as at 120, and an open bottom as at 122. The opening 12) is arranged so that the thermo-sensitive power element is exposed to the direct heat radiation from the shell of the unit 62. The air after cooling the condenser and flowing upwardly into the machine compartment may enter through bottom opening 122 to influence or effect a modification of the influence of the shells heat upon the ythermo-sensitive power element.

In operation to cool the food storage compartment 22,

the vaporized or heat laden refrigerant is withdrawn from the evaporator into the accumulator wherein theliquid refrigerant is separated from the vaporized, the vaporized or gaseous refrigerant is .conducted into the motor compressor unit 62 to be compressed by` the compressor and discharged to flow through the condenser 64.- The refrigerant first flows through the plate section 66 and then the section 68 of the condenser to be cooled, condensed and then metered and conducted through a small diameter conduit to the evaporator coils 70.

Normally, during periods when the ambient temperature is preferably below 80 F., the condenser and motorcompressor unit may be effectively cooled by natural flow of air passing thereover. Air enters through opening 44 into the space 46 to flow over and around the condenser section 66 then passes upwardly into the machine compartment to cool the motor-compressor unit and passes through opening 52 outwardly to the atmosphere. Vaporous refrigerant in the section 68 of the condenser is cooled and condensed by the air circulating about the exterior of the cabinet. When the ambient temperature attains about 80 F. cooling by natural convection is ineffective for eicient operation and as the temperature of the refrigerant rises there is a corresponding rise in temperature in the motor-compressor unit to iniiuence and actuate the thermostatic control 112 to energize the motor 81) and operate the fan 84 for the forced circulation of air which is drawn through opening 52 into the machine compartment to cool the motor-compressor unit then pass through space 46 to cool the condenser section 66 to pass outwardly through opening 44 to the atmosphere. An opening 130 is formed in the front rail 34 to provide an additional access opening for circulation of air about the condenser 66.

The thermostatic control 112 is arranged to be connected in series with the thermostatic control 110 (see Fig. A6) so that the fans motor 80 will be energized during periods that the motor-compressor is operating. However, the fans motor 80 will only be energized whenever the ambient temperature rises so that cooling by natural convection is ineffective and forced circulation of air is essential.

The above arrangement is such that by forming a portion of the condenser to lie in the path of a channelled air stream and a portion of the condenser bonded to the eX- terior Wall of the cabinet to utilize the wall to radiate heat therefrom, there is a compact arrangement for providing a large surface area necessary when natural convection cooling is desired. Further this arrangement also permits the refrigerant to be consecutively cooled by air of the same temperature that is the air passing around the condenser section 66 does not serve to cool the exterior walls of the cabinet while the air cooling the exterior of the cabinet does not serve to cool the condenser section 66 and the motor-compressor unit. Also, as the air entering the space 44 only serves to cool the portion 66 of the condenser 64 it would not become so heated as to be in-` effective to cool the motor-compressor unit before passing to the atmosphere. However, when ambient temperature rises above F., the fan motor S0 is energized to operate the fan for passing air across the compressor unit then the condenser 66. The condenser 66 is so arranged that when forced air circulation is provided it will effectively cool and condense the compressed refrigerant therein so that little or no further cooling is required of the refrigerant as it passes through the condenser section 68 thereby permitting the exterior wall of the cabinet to be held at atmospherical temperature and heat leakage to the food compartment is held at a minimum.

Although only a preferred form of the invention has been illustrated, and that form described in detail, it will be apparent to those skilled in the art that various moditications may be made therein without departing from the spirit of the invention or from the scope of the appended claim.

I claim:

Refrigerating apparatus comprising a cabinet having a food storage compartment and a second compartment having an open bottom and an open side, refrigerating means for said food storage compartment including an evaporator, a motor-compressor unit, a condenser connected to said motor-compressor unit, said condenser having a first section and a second section connected in series relation, said first section being arranged in horizontal position in the lower part of said second compartment, said second section being bonded in thermal heat exchange relation to the outer wall of said cabinet and being isolated from said motor-compressor unit and the condenser first section, said motor-compressor unit being positioned in said second compartment adjacent to and above said condenser first section so that heat dissipated from said condenser first section passes by natural convection over said motor-compressor unit and out the open side of said second campartment, temperature responsive fan means for causing the circulation of air through the open side of said second compartment and oversad motor-compressor unit and then over said first section of said condenser and out the bottom side of said second compartment, and thermostatic means for controlling the operation of said fan means, said thermostatic means being arranged to be responsive to the environment temperature about said motor-compressor unit.

References Cited in the tile of this patent UNlTED STATES PATENTS Y 1,769,119 Davenport July 1, 1930 2,135,091 Newill Nov. 1, 1938 2,238,511 Thaxter Apr. 15, 1941 2,706,387 Swanson Apr. 19, 1955