US2070457A - Evaporator for refrigerating machines - Google Patents

Description

C. STEENSTRUP EVAPORATOR FOR REFRIGERATING MACHINES 2 Sheets-Sheet 1 Filed Dec. 6, 1934 IY1\/T"ltOY Christian Steenstv up,

b 8. EMMA/1M1 y is tormey;

Feb 9, 1937.

Feb. 9, 1937. c. STEENSTRUP EVAPORATOR FOR REFRIGERATING MACHINES 2 Sheets-Sheet 2 Filed Dec. 6, 1934 ITWVETTCOT. Christian SteenstPup,

by 6. mm His ttorney.

Patented Feb. 9, 1937 Christian Steenstrup, Schnectady, N. Y., assignor to General Electric Company, a corporation of New York Application December 6, 1934,-Serial No.756,244

6 Claims. (c1. 62-99) My invention relates to evaporators for refrigerating machines. i

It is an object of my invention to provide. an

evaporator for refrigerating machines having an improved arrangement for circulating refrigerant which will provide adequate ice freezing and air cooling capacity.

Another object of my invention is to provide an evaporator including an air cooling portion providing a compartment to be cooled and a shelf arranged within the compartment which shall occupy a minimum amount of space and shall afford an adequate circulation of air about the shelf.

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

For a better understanding of my invention reference may be had to the accompanying drawings in which Fig. 1 is a sectional view of a household refrigerator cabinet having an evaporator embodying myv invention; Fig. 2 is a detailed perspective view of a portion of the evaporator and shelf construction shown in Fig. 1, and Fig. 3 is a modified form of the evaporator.

Referring now to the drawings, in Fig. 1, I

have shown a household refrigerator including a cabinet having an outer metal wall l0 provided with a partition II. A food compartment I2 is formed above the partition H by an inner metal wall or liner l3 spaced from the outer wall Ill and from the partition II. The space between the inner wall l3 and the wall l0 and the partition II is filled with heat insulation l4, and the compartment I2 is provided with an insulated door or cover IS. A refrigerant conduit I6 is associated with the wall l3 to cool the compartment 12. In the construction illustrated the conduit I6 is secured in heat exchange relation to the outer surface of the wall l3 and provides a passage for refrigerant uti- 5 lized to cool the compartment l2. A refrigerated shelf I1 is secured within the compartment to support freezing trays or the like. In order to supply refrigerant to the conduit IS, a motor and compressor unit is arranged within acasing I'I mounted on supports i8 within the space below the partition H. Gaseous refrigerant is compressed by the compressor within the casing I1 and is discharged through a connection i9 communicating direct y with the discharge port of the compressor and enters a condenser is described and claimed in my copending apconduit 20 secured on the inner surface of the outer wall III of the cabinet. The refrigerant is partially liquefied within the conduit 20 and passes upwardly through a tube 2| to another condenser conduit 22 also secured to 5 L the inner surface of the outer wall it.

This condenser construction wherein the conduit is secured in heat exchange relationship to the outer wall of the refrigerator cabinet 10 plication, Serial No. 554,623, filed August 3, 1931, and assigned to General Electric Company, assignee of my present application.

The liquefied refrigerant condensed in the conduits 20 and 22 flows through a connection 23 to a receiver or float valve chamber 24. When a predetermined amount of liquid refrigerant has been collected in the chamber 24, a float valve therein operates to discharge the liquid through a connection 25 to the conduit IS. The liquid refrigerant is partially vaporized in the conduit 16 by the absorption of heat from the chamber I2, and a mixture of liquid and gaseous "refrigerant flows through the end 26 of the conduit l6 and into a U-shaped tube 21' connecting one end of a passage 28 in the shelf I! with a header 29 arranged within the insulation I4. The header 29 communicates with the other end of the passage 28 through a connection tube 30. The header 29 is arranged so that it will maintain a level of liquid refrigerant above the level of the shelf i1, thereby maintaining liquid refrigerant within the passage 28 at all times and flooding the same. The liquid and gaseous refrigerant entering the tube 21 induce .a circulationof refrigerant therein upwardly into the passage 28 and through the passage and the connection 30 to the header, liquid refrigerant from the header flowing down through the other leg of the U-shaped tube 21 and recirculating through the tube and the passage 28. The vaporized refrigerant collects within the header 2! and is withdrawn therefrom through a suction conduit 3| and returns to the casing H, the interior of the casing being at the low pressure" existing on the intake side of the compressor therein. L

The construction of the shelf l'! and the header 29 is clearly shown. in Fig. 2. The shelf l1 comprises a single sheet of metal, one-half of which is provided with indentations forming the sinuous passage 28. the two halves of the shelf being folded together and secured as by weldingabout the edges and between the indentations to sealthe passage. The upper half of the shelf 55 g is provided with upturned flanges 32, which are secured by bolts 33 to the inner wall 13. The

side 34 of the shelf, which is near the wall l3 is spaced therefrom in order to afford free circulation of air about the shelf. The path of circulation of the refrigerant during operation of the refrigerating machine is indicated by ar-' pressor.

In Fig. 3 I have shown a modification in which the liquid and gaseous refrigerant from the conduit I5 is injected into the leg of the U-shaped tube 2! which is connected to the header, thereby inducing a flow of refrigerant in the opposite direction through the shelf 28. When the connections are made in this manner the passage 28 is always completely filled with liquid refrigerant which may be superheated by the absorption of heat from articles placed on the shelf, but which will not be vaporized until the pressure is released as it flows upwardly past the point of injection of refrigerant from the conduit l6, at which point the vapor will flash out and rise to the header 29. In either of the modifications of my invention there is provided a rapid circulation of refrigerant through the freezing shelf l1 and an adequate freezing capacity is insured. At the same time the conduit l6, which is arranged on the three sides of the wall l3 other than the side on which -the shelf is mounted, provides adequate and uniform cooling of the compartment.

From the foregoing it will readily be apparentthat I have provided an improved evaporator for refrigerating machines having a shelf which requires a minimum amount of space within the compartment to be cooled, and provides an adequate circulation of refrigerant for cooling the air in the compartment and for freezing purposes.

While I have shown and described my invention as applied to a household refrigerating machine, I do not desire my invention to be limited to the particular construction shown and described, and I intend in the appended claims to cover all modifications within the spirit and scope of my invention.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. A flooded evaporator for refrigerating machines including a metal wall constituting a portion of the liner of 'a compartment to be cooled, means including a refrigerant conduit secured in heat exchange relation to said wall for cooling said compartment, means including a shelf having a refrigerant passage therein for supporting freezing trays and the like within said compartment, said shelf being arranged in the upper portion of said compartment and being spaced from said wall to provide circulation of air through said compartment and between said shelf and said wall, means including a refrigerant containing header for flooding the passage in said shelf, means including tubes for providing communication between said header and both ends of the passage in said shelf, and means providing communication between said conduit and one of said tubes for inducing a circulation of refrigerant through said shelf and for producing recirculation of refrigerant through said header and said shelf.

2. A flooded evaporator for refrigerating machines including a metal wall constituting a portion of the liner of a compartment to be cooled, means including a refrigerant conduit secured in heat exchange relation to said wall for cooling said compartment, means including a shelf comprising a single sheet of metal folded on itself and having indentations therein forming a refrigerant passage for supporting freezing trays and the like within said compartment, said shelf being arranged in the upper portion of said compartment and being spaced from said wall to provide circulation of air through said compartment and between said shelf and said wall, means including a refrigerant containing header for flooding the refrigerant passage in said shelf, means for providing communication between said header and both ends of the passage in said shelf, means providing communication between said conduit and said communicating means for inducing a circulation of refrigerant through said shelf and for producing recirculation of refrigerant through said header and said shelf.

3. A flooded evaporator for refrigerating machines including a metal wall forming a compartment to be cooled, means including a refrigerant conduit secured in heat exchange relation to said wall for cooling said compartment, means including a shelf having a refrigerant passage therein for supporting freezing trays and the like within said compartment, said shelf being arranged in the upper portion of said compartment and being spaced from said wall to provide circulation of air through said compartment and between said shelf and said wall, means including a refrigerant header and tubes connecting said header with the passage in said shelf for maintaining a level of liquid refrigerant above the level of the passage in said shelf, and means providing communication between said conduit and one of said tubes for inducing a circulation of refrigerant through said shelf and for producing recirculation of refrigerant through said header and said shelf.

4. A flooded evaporator for refrigerating machines including a metal wall forming a compartment to be cooled, means including a'refrigerant passage in heat exchange relation to said wall for cooling said compartment, means including a shelf having a refrigerant passage therein for supporting freezing trays and'the like within said compartment, said shelf being arranged in the upper portion of said compartment and being spaced from said wall to provide circulation of air through said compartment and between said shelf and said wall, means including a refrigerant header and connecting said header with the passage in said shelf for maintaining a level of liquid refrigerant above the level of the passage in said shelf, said last men tioned means further including a U-shaped passage extending downwardly from said header, and means providing communication between said passage in heat exchange relation with said wall and one leg of said U-shaped passage and injecting refrigerant upwardly into said one leg for producing recirculat on of refrigerant through said header and said she f.

5. A flooded evaporator for refrigerating machines including a metal wall forming a compartment to be cooled, means including a refrigerant passage arranged in heat exchange relation to said wall for cooling said compartment, means including. a shelf having a refrigerant passage therein for supporting freezing trays and the like within said compartment, said shelf being arranged in the upper portion of said compartment and being spaced from said wall to provide circulation of air through said compartment and between said shelf and said wall, means including a refrigerant header and connecting said header with the passage in said shelf for maintaining a level of liquid refrigerant above the level of the passage in said shelf, and means providing communication between said passage in heat exchange relation with said wall and said means connecting said header and shelf and injecting refrigerant into said connecting means toward the passage in said shelf for inducing a rapid circulation of refrigerant through said shelf and into said header and for producing recirculation of liquid refrigeran through said header and said shelf.

6. A flooded evaporator for refrigerating machines including a compartment having four metal side walls. means including a refrigerant conduit secured to three of said side walls for cooling said compartment, means including a shelf arranged near the fourth of said walls and having a refrigerant passage therein for supporting freezing trays and the like within said compartment, said shelf being arranged near the top of said compartment and being spaced from said fourth wall to provide circulation of air through said compartment and between said shelf and said fourth wall, means including a header communicating with both ends of the passage in said shelf for maintaining .a level of liquid refrigerant above the level of said shelf, and means providing communication between said conduit and said shelf for inducing a circulation of refrigerant through said shelf and for producing a recirculation of refrigerant through said shelf and said header.

CHRISTIAN STEENSTRUP.

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