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Publication numberUS3289426 A
Publication typeGrant
Publication dateDec 6, 1966
Filing dateFeb 17, 1966
Priority dateFeb 17, 1966
Publication numberUS 3289426 A, US 3289426A, US-A-3289426, US3289426 A, US3289426A
InventorsDean Music Earl
Original AssigneeDean Music Earl
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Lubricating refrigeration systems
US 3289426 A
Abstract  available in
Images(2)
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Claims  available in
Description  (OCR text may contain errors)

Dec. 6,. 19%6 E. D. MUSIC EEWAZG LUBRICATING REFRIGERATION SYSTEMS Filed Feb. 17, 1966 2 Sheets-Sheet l I? LEE-5T2 mviimog. EAQL 0, Mus/ 0 Dec. 6, 1966 E. D. MUSIC 3389 426 LUBRICATING REFRIGERATION SYSTEMS Filed Feb. 17, 1966 2 Sheets-Sheet B INVENTOJ 5/4131 0o Mus/c W Q WQZW United States Patent 3,289,426 LUBRICATING REFRIGERATION SYSTEMS Earl Dean Music, 416 S. Main, Elk City, ()kla. Filed Feb. 17, 1966, Ser. No. 548,113 12 Claims. (Cl. 6277) This is a continuation-in-part of applicants co-pending application of the same title, Serial No. 430,984, filed February 8, 1965.

This invention relates to an improved method and apparatus for lubricating a refrigeration system.

As is well known in the art, most refrigeration systems utilized in homes and commercial buildings utilize a compressor, condenser, evaporator and an expansion device between the condenser and the evaporator. As is also well known, such refrigeration systems periodically require the addition of oil for lubrication of the compressor and the motor driving the compressor.

In the past it has been the practice to pump the refrigeration system down in order to lubricate the compressor and motor, which action requires a substantial period of time. Also, pumping the system down and sucking lubricating oil into the system almost invariably leaves a slight amount of air and moisture in the refrigeration system. Further, servicemen frequently get dirt in the compressor during the lubrication of the compressor as it has been practiced in the past.

The present invention contemplates a novel method of lubricating a refrigeration system having a compressor, comprising the steps of partially filling a container assembly with lubricant for the refrigeration system; forcing refrigerant of the type used in the refrigeration system under pressure through the container assembly above the lubricant therein to remove substantially all of the air from the container assembly. The container assembly is then inverted and the lowermost end of the inverted container assembly is connected to the suction side of the compressor. Refrigerant is then applied to the container assembly under a pressure greater than the suction pressure of the compressor to fill the space above the lubricant in the inverted container assembly and force lubricant from the container into the compressor suction until the desired amount of lubricant has been supplied to the refrigeration system.

The present invention also contemplates a novel system for lubricating a refrigeration system having a compressor, While the refrigeration system is in operation, comprising an invertible container assembly having an upper end and a lower end and having inlet and outlet connectors on the upper end thereof. A supply of lubricant is contained in the container assembly and partially fills the container assembly, and a hose is connected to the outlet of the container assembly, and to the suction side of the compressor. Means are provided, such as in the form of a bottle of refrigerant and a control valve, for forcing refrigerant under pressure through the upper portion of the container assembly and the hose when the container assembly is in an upright position to remove air from the upper portion of the container assembly and the hose, and for filling the space above the lubricant for forcing the lubricant from the container and through the hose into the suction of the compressor when the container is in an inverted position.

An object of the invention is to decrease the cost of lubricating a refrigeration system which has been in operation.

Another object of the invention is to minimize the time required for lubricating a refrigeration system.

A further object of the invention is to lubricate a refrigeration system without injecting air or moisture into the refrigeration system.

Another object of the invention is to lubricate a refrigeration system while the refrigeration system is in operation.

A still further object of this invention is to provide a system for lubricating a refrigeration system which utilizes primarily readily available equipment, is economical and will have a long service life.

Other objects and advantages of the invention will be evident from the following detailed description when read in conjunction with the accompanying drawings which illustrate the invention.

In the drawings:

FIG. 1 is a diagrammatic view of a refrigeration system and my invention applied thereto.

FIG. 2 is a vertical sectional view through one form of lubricant container utilized in the present invention.

FIG. 3 is a vertical sectional view through a modified form of lubricant container assembly utilized in the present invention.

FIG. 4 is a diagrammatic view of a portion of a refrigeration system of the type shown in FIG. 1, showing use of the modified container assembly.

Referring to the drawings in detail, and particularly FIG. 1, reference character It] generally designates a typical refrigeration system comprising a compressor 12 and a motor 14 for the compressor constructed as an integrated unit, such as in a hermetically sealed unit. The discharge 16 of the compressor 12 is connected by a suitble conduit 18 to a condenser 20. Refrigerant is condensed in the condenser 20 by the cooling action of air forced over the condenser by a motor driven fan 22. The condensed refrigerant is conveyed through a capillary tube 24 to an evaporator 26. The refrigerant is vaporized in the evaporator 26, thus absorbing heat, and is returned to the suction 28 of the compressor 12 through a suitable conductor 34).

A conventional service valve 32 is interposed in the tube 30. One port 34 of the service valve 32 is connected to that portion of the tube 30 leading to the evaporator 26, and a port 36 of the service valve is connected to an extension 30a of the tube 30 leading to the suction 28 of the compressor 12. The service valve 32 is also provided with what is normally considered a service port 38 and an operating stem 40. In one position of the stem 40, the ports 34 and 36 are placed in communication and the service port 38- is isolated for the normal operation of the refrigeration system 10. When the stem 40 is threaded a short distance into the service valve 32, the service port 38 is connected to the ports 34 and 36, and when the stem 40 is threaded all the way into the service valve 32, the service port 38 is connected to the port 36, but the port 34 is closed off.

The present invention contemplates a novel container assembly 42 connected to the service port 38 of the service valve 32 by a tube or hose 44, and to a bottle 46 of refrigerant by means of a hose 48. The refrigerant in the bottle 46 will be the same type of refrigerant used in the refrigeration system 10 and may be, for example, dichlorodifiuoromethane, sold under the tradename of Freon. The refrigerant in the bottle 46 will be at a pressure higher than the pressure of the refrigerant in the system 10 at the suction side 28 of the compressor 12. For example, the pressure of Freon-22 at the suction 28 of the compressor 12 may be 78 p.s.i. with an outside temperature of and the pressure of the refrigerant in the bottle 46 may be p.s.i. under the same atmospheric conditions. It should also be noted here that a suitable hand-operated valve 50 is interposed in the hose 48 between the bottle 46 and the container 42 for controlling the flow of the refrigerant from the bottle 46.

The container assembly 42 is shown in detail in FIG. 2 and comprises any suitably-shaped container 51 of sufiicient strength to withstand the maximum pressure to be applied thereto from the bottle 46. In the embodiment shown in FIG. 2, the container 51 is a cylindrical metal can having an externally threaded neck 52 at the upper end 54 thereof. A suitable cap 56 is threaded for screwing onto and off of the neck 52 and is provided with a sight glass 58 in the top thereof. The sight glass 58 may be any suitable transparent material sealed in a mating aperature 60 in the cap 56 in order that the operator of the system can see into the container 51, as will be more fully set forth below.

An inlet connector 62 extends through a mating aperture 64 in one wall of the cap 56 and is preferably turned downwardly at its inner end 66 to approximately the lower end of the neck 52. The connector 62 is secured and sealed in the aperture 64 in any suitable manner, such as by welding 68. The outer end 70 of the connector 62 is externally threaded for connection with the hose 48 by suitable hose connector, not shown in detail.

An outlet connector 72 is secured in a mating aperture 74 in the opposite wall of the cap 56 in any suitable manner, such as by welding 76. The outer end 78 of the connector 72 is also externally threaded for connection with the hose 44. Finally, a supply of lubricant 80 is deposited in the container 51, partially filling the container 51.

In use of the present invention, the inlet connector 62 of the container assembly 42 is connected to the refrigerant bottle 46 by the hose 48, and one end of the hose 44 is connected to the discharge connector 72 of the container. The container assembly 42 is then held in an upright position as indicated by the dashed lines in FIG. 1 and the valve 50 is momentarily opened. It will then be seen that refrigerant from the bottle 46 will pass through the hose 48 and into the upper portion of the container assembly 42 through the inlet connector 62. This refrigerant will then pass out through the outlet connector 72 and through the hose 44. The refrigerant thus passed through the hose 48, the container assembly 42 and the hose 44 will clear the upper portion of the container assembly above the level of the lubricant 80, as well as the hoses 48 and 44, of air and moisture which may be entrained therein. It will also be evident that these portions of the system will then be filled with vapor ized refrigerant and such conditions will be maintained at least momentarily.

As soon as the valve 50 is closed, the end 82 of the hose 44 is connected to the service port 38 of the service valve 32, and the container assembly 42 is inverted as shown in full lines in FIG. 1. The stem 40 of the service valve 32 is operated to place the service port 38 in communication with the ports 34 and 36, and the valve 50 is opened. The higher pressure refrigerant in the bottle 46 will then flow through the hose 48 into What is now the lower end of the container assembly 42 and then upwardly through the lubricant to the space in the container above the lubricant. The refrigerant thus forces the lubricant 80 through the outlet connector 72, hose 44, service valve 32 and hose portion a into the suction 28 of the compressor 12. The operator observes the sight glass 58 during this operation and will thus be able to tell when all of the lubricant 80 has been removed from the container assembly 42. As soon as all of the lubricant 80 is forced into the compressor 12, the stem of the service valve 32 is turned to the position where the ports 34 and 36 are in communication but the service port 38 is isolated. As soon thereafter as possible, the valve is closed to close off the bottle 46 from the container assembly 42.

Upon completion of the above operation, the hoses 44 and 48 may be disconnected from the service valve 32 and container assembly 42. The cap 56 of the container assembly is then removed and a new supply of lubricant 80 placed in the container 51. The lubricant 80 will normally be a high grade mineral lubricant. When the desired quantity of lubricant is deposited in the container 51, the cap 56 is threaded back onto the neck 58 and suitable protector caps (not shown) are then preferably placed over the outer ends 70 and 78 of the connectors 62 and 72 to prevent the entrance of dirt into the container assembly 42. The lubrication system will then be ready for another service job at a different location. It will be readily understood, however, that the cap 56 may be permanently secured on the container 51 and the entire container assembly disposed of at the completion of a service job.

It may also be noted at this point that the amount of lubricant in the container 51 may be easily designed to be the normal amount of lubricant added to a refrigeration system of the type being serviced, in which event the entire amount of lubricant 80 is forced into the refrigeration system in the manner set forth above. On the other hand, the container 51 may be large and more lubricant 80 contained therein than is normally placed in a refrigeration system 10. In this latter event, the operator would need to time the injection of lubricant into the refrigeration system or provide a transparent graduated scale in the side wall of the container 51.

An alternate embodiment of the invention is illustrated in FIGS. 3 and 4. This embodiment of the invention utilizes a modified container assembly which includes a container portion 102 and a valve portion 104. The container portion 102 is a sealed container 106 preferably in the form of a metal can of the type presently used for storing small amounts of refrigerant under pressure. The container 106 includes an externally threaded neck 108 on the upper end thereof forming a connector for the valve portion 104, as will be described. The upper end of the connector 108 is closed by a sealing material 110, in the conventional manner, which may be pierced by a piercing valve. The container 106 also includes an annular projection 112 positioned concentrically around the connector 108 in the usual fashion. The lubricant supply 80 is vacuum-packed in the container 106 and only partially fills the container 106. By being vacuumpacked, the container 106 is less likely to have moisture condensed therein when the container is stored under varying climatic conditions and, of course, the container then also contains a very nominal amount of air.

The valve portion 104 preferably comprises what is known as a double port, piercing-type valve, such as is manufactured by Watsco, Inc. of Hialeah, Florida, under the designation Twin Port, Can Tap Valve. The valve 104 includes a body portion 114 having externally threaded connectors 116 and 118 on the opposite sides thereof forming ports 120 and 122 for the valve. The lower end 124 of the valve is internally threaded for connection with the externally threaded connector 108 of the contanier 106. The lower end of the valve 104 also includes a sealing ring 126 positioned to seal the upper end 110 of the connector 108 when the upper end 110 is pierced by the stern 128 of the valve, as will be more fully set forth below.

The valve stem 128 is threaded into the bore or valve chamber 130 of the valve and is normally retained in place in the valve by a cap portion 132 threaded around the upper end of the valve body 114. A suitable handle 134 is secured to the upper end of the valve stem 128 for turning the valve stem and thus raising and lowering the valve stem in the valve body, as will be described. The valve 104 also includes a locking ring 136 threadedly secured around the valve body 114 below the connectors 116 and 118 for engagement with the annular projection 112 on the container 106 in the usual manner. It should also be noted here that the valve 104 is shown as being almost completely formed of a plastic material, although it will be understood that the valve may be formed of any desired material which will withstand the pressure to be encountered.

In use of the modified container assembly 100, the lubricant 80 is first vacuum-packed in the container 106 in the manner described to remove substantially all of the air from the container and minimize the possibility of moisture condensing in the container during transportation and storage. When it is desired to lubricate a re frigeration system, the valve 104 is threaded onto the connector 108 of the container 106, and the locking ring 136 is threaded down into engagement with the projection 112 to firmly secure the valve 104 on the container 106. It will, of course, be understood that the valve stem 128 is retracted into the body 114 while the valve is being secured on the container.

The container assembly 100 is then connected to the refrigeration system as partially shown in FIG, 4. It will there be noted that the hose 48 leading from the refrigerant supply is connected to the connector 118 of the valve 104, and one end of the hose 44 is secured to the opposite connector 116 of the valve. During this initial portion of the operation, the opposite end 82 of the hose 44 is not connected to the service valve 32.

While the container assembly 100 is retained in an upright position as illustrated by the dashed lines in FIG. 4, the valve 50 is momentarily opened to pass a charge of refrigerant through the hose 48; the part 122 of the valve 104; the valve chamber 130; the opposite port 120 of the valve 104, and through the hose 44 to remove air and moisture from the hoses 47 and 44 and the valve 104. During the operation just described, the valve stem 128 may either be in a retracted position removed from the end 110 of the container connector 108, or the pointed end of the stem 128 may be in a piercing position extending partially through the end 110 of the connector 108. In either event, the valve chamber 130 is closed from the interior of the container 106. As long as the lower, pointed end of the valve stem 128 is in a position extending into the end 110 of the connector 108, the sealing ring 126 effectively prevents communication between the valve chamber 130 and the container 106.

The container assembly 100 is then inverted to the full line position shown in FIG. 4, and the end 82 of the hose 44 is connected to the service port 38 of the service valve 32, while the service valve 32 is maintained in a position to close the service port 38 from the ports 34 and 36. The piercing valve 104 is then operated by turning the handle 134 to pierce the seal 110 in the connector 108 of the container 106 and then to withdraw the pointed end of the stem 128 into the valve chamber to provide communication between the valve chamber 130 and the interior of the container 106. When such communication is established, the valve 50 is opened for a short period of time to direct high pressure refrigerant through the hose 48, the port 122 of the valve 104, the valve chamber 130 and into the container 106 to fill the space in the container which will then be above the level of the lubricant 80 in the inverted container. As soon as a supply of the high pressure refrigerant is thus introduced into what is then the upper end of the container 106, the valve 50 is closed and the service valve 32 is operated to provide communication between the service port 38 and the port 36 communicating with the suction of the compressor 12 through the hose portion 30a. As soon as this lastdescribed communication is established, the high pressure refrigerant in the top of the container 106 forces the lubricant 80 through the upper end 110 of the container connector 108; the valve chamber 130; the port 120; the hose 44, the service valve 32, and the hose portion 301; into the suction 28 of the compressor 12. The lubricant 80 will thus be introduced into the refrigeration system in only a matter of minutes; whereupon the service valve 32 is again operated to close off the service port 38 from either of the ports 34 or 36 in the manner described above.

In the embodiment of the invention illustrated in FIGS. 3 and 4, the piercing valve 104 will, of course, be used in a large number of successive lubricating jobs. Since the lubricant in this embodiment is vacuum-packed in the container 106, the container 106 will normally be disposed of after being used in a lubricating operation and a new container 106 will be required for the next lubricating job. However, the container 106 could be saved and returned to the supplier of the vacuum-packed lubricating oil for reuse 'by rescaling the upper end 110 of the connector 108. Insofar as the service man is concerned, however, a new container 106 containing the vacuum-packed lubricant 80 will be used in each lubricating job, assuming the container 106 is sized to retain the desired amount of lubricant 80 for the particular refrigeration system being lubricated. In the event the container 106 being used contains a larger or excessive amount of lubricant 80, the valve 104 may be moved to the position illustrated in FIG. 3 when the service man determines the desired amount of lubricant 80 has been ejected into the refrigeration system. In this position of the valve 104, as previously noted, the seal 126 effectively seals the valve chamber 130 from the interior of the container 106. Thus, the container 106 could then be used in a subsequent lubricating job by following the same operating procedure outlined above.

From the foregoing it will be apparent that by use of the present invention a refrigeration system may be lubricated while the refrigeration system is in operation. The service valve may be easily manipulated to connect all of the ports therein while lubricant is being forced into the compressor and maintain the normal flow of refrigerant through the refrigeration system. Since the refrigeration system does not need to be pumped down, the minimum time will be required to lubricate the refrigeration system. It will also be apparent that in use of the present invention no air, moisture or dirt will be introduced into the refrigeration system.

Changes may be made in the combination and arrangement of parts or elements, as well as in the steps and procedures, heretofore set forth in the specification and shown in the drawings without departing from the spirit and scope of the invention as defined in the following claims.

What is claimed is:

1. A method of lubricating a refrigeration system having a compressor comprising:

partially fill-ing a container with lubricant for the refrigeration system;

forcing refrigerant under pressure through the container above the lubricant therein to remove substantially all of the air from the container; inverting the container; connecting the then lowermost end of the inverted container to the suction side of the compressor; and

applying refrigerant to the container under a pressure greater than the suction pressure of the compressor to force lubricant from the container into the compressor suction until the desired amount of lubricant has been supplied to the refrigeration system.

2. A method of lubricating a refrigeration system having 'a compressor, comp-rising:

partially filling a container with lubricant for the refrigeration system;

connecting a hose to the upper end of the container;

forcing refrigerant under pressure through the container above the lubricant therein to remove substantially all of the air from the container and said hose;

inverting the container;

connecting said hose to the suction side of the corn pressor; and

applying refrigerant to the container under a pressure greater than the suction pressure of the compressor to force lubricant from the container through said hose into the compressor suction until the desired amount of lubricant has been supplied to the refrigeration system.

3. A method of lubricating a refrigeration system having a service valve interposed in the connect-ion of the evaporator to the compressor of the system, and wherein the service valve has a service port, comprising:

connecting a bottle of refrigerant gas under a pressure greater than the pressure at the suction side of the compressor to the top of a container partially filled with lubricant;

connecting one .end of a hose to the top of said container;

discharging a quantity of refrigerant from the bottle through the top of said container and hose to remove air therefrom;

connecting the opposite end of said hose to the service port of the service valve;

inverting said container;

opening the service valve to communicate the service port with the compressor;

passing refrigerant from the bottle through said inverted container and hose into the refrigeration system until the desired amount of lubricant has been forced from said container into the refrigeration system; then operating the service valve to isolate the service port from the refrigeration system.

4. A method of lubricating an operating refrigeration system having a service valve interposed in the connection of the evaporator to the compressor of the system, and wherein the service valve has a service port, comprising:

connecting a bottle of refrigerant gas under a pressure greater than the pressure at the suction side of the compressor to the top of a container partially filled with lubricant;

connecting one end of a hose to the top of said eontainer;

discharging a quantity of refrigerant from the bottle through the top of said container and hose to remove air therefrom;

connecting the opposite end of said hose to the service port of the service valve;

inverting said container;

opening the service valve to communicate the service port with the compressor and the evaporator of the refrigeration system;

passing refrigerant from the bottle through said container and hose into the refrigeration system until the desired amount of lubricant has been forced from said container into the refrigeration system; then operating the service valve to isolate the service port from the refrigeration system.

5. A system for lubricating a refrigeration system having a compressor while the refrigeration system is in operation, comprising:

an invertible container having an upper end and a lower end and having inlet and outlet connectors on the upper end thereof;

a supply of refrigeration lubricant partially filling the container;

a hose for connecting the outlet of the container to the suction side of the compressor; and

means for forcing refrigerant under pressure through the upper portion of the container and said hose when the container is in an upright position to remove air from the container and hose, and for forcing the lubricant from the container through the hose into the suction of the compressor with refrigerant when the container is in an inverted position.

6. A system as defined in claim wherein said container has a cap secured on the upper end thereof, and said inlet and outlet connectors are secured in sadi cap.

7. A system as defined in claim 6 characterized further to include a sight glass in said cap to indicate the removal of lubricant from the container when the container is inverted.

8. Asystem as defined in claim 6 wherein said cap is threadedly connected to said container to facilitate replenishing the lubricant in the container.

9. A method of lubricating a refrigeration system having a compressor, comprising:

partially filling a container with lubricant for the refrigeration system; connecting one end of a hose to the container; passing refrigerant through the hose to clean the hose of air and moisture; inverting the container; filling the space above the lubricant in the inverted container with a supply of refrigerant under a pressure greater than the suction pressure of the compressor; and connecting the opposite end of the hose to the suction of the compressor, whereby said refrigerant under pressure forces the lubricant through the hose into the compressor while the compressor is in operation. 10. A method of lubricating a refrigeration system having a compressor and a service valve connected to the suction of the compressor, and wherein the service valve has a service .port, comprising:

vacuum packing lubricant for the refrigeration system in a sealed container wherein the container is only partially filled with lubricant;

securing a double ported, piercing valve to the container above the lubricant in the container;

connecting one end of a hose to one of the ports of the piercing valve;

passing refrigerant through the opposite port of the piercing valve, the piercing valve above the container and on through the hose to clear these members of air and moisture;

connecting the opposite end of the hose to the service port of the service valve While the service port of the service valve is closed;

piercing the container with the piercing valve above the level of lubricant in the container and communicating the interior of the container with the interior of the piercing valve while communicating a supply of refrigerant under a pressure greater than the suction pressure of the compressor to the interior of piercing valve through said opposite port;

closing said opposite port of the piercing valve;

inverting the container, whereby the supply of refrigerant formerly in the top of the container will pass through the lubricant in the container and again be above the lubricant in the container; and

opening the service port of the service valve to the compressor suction, whereby the refrigerant in the container forces the lubricant from the container through the piercing valve hose and service valve into the compressor suction.

11."A system for lubricating a refrigeration system having a compressor while the refrigeration system is in operation, comprising:

an invertible container assembly having an upper end and a lower end and having inlet and outlet connectors on the upper end thereof;

a supply of refrigeration lubricant partially filling the container assembly;

a hose for connecting the outlet of the container assembly to the suction side of the compressor; and

means for forcing refrigerant under pressure through the upper portion of the container assembly and said hose when the container assembly is in an upright position to remove air from the upper portion of the container assembly'and the hose and for filling the space in the container above the lubricant when the container is in an inverted position for forcing the lubricant from the container through the hose into the suction side of the compressor.

12. A system for lubricating a refrigeration system having a compressor while the refrigeration system is in operation, comprising:

9 a sealed container having refrigerant lubricant vacuumpacked therein partially filling the container, said container having a threaded connector thereon;

a double ported piercing valve sized to be connected References Cited by the Examiner UNITED STATES PATENTS Peo 62-77 Wood 6277 Shoemaker 62149 Haas 62-192 X Ehrens 6 2-292 Alexander 6277 ROBERT A. OLEARY, Primary Examiner.

l5 LLOYD L. KING, Examiner.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US2162537 *Nov 13, 1935Jun 13, 1939Houde Eng CorpRefrigerating system
US2214699 *Apr 8, 1939Sep 10, 1940Westinghouse Electric & Mfg CoRefrigeration method
US2499170 *Oct 15, 1947Feb 28, 1950Philco CorpCharging apparatus
US2680956 *Dec 19, 1951Jun 15, 1954Haskris CoPlural stage refrigeration system
US3093979 *Jan 19, 1961Jun 18, 1963Henry EhrensApparatus for storing and dispensing refrigerant gas
US3225554 *Nov 3, 1964Dec 28, 1965William O AlexanderPressure injector
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3443392 *Feb 14, 1968May 13, 1969Alexander William OProcess for restoration of burned out hermetic refrigeration system
US3873289 *Jan 2, 1974Mar 25, 1975Kenneth R WhiteAir conditioner servicing unit
US4288993 *Sep 24, 1979Sep 15, 1981U.S. Philips CorporationRefrigerator
US4698983 *Jun 11, 1986Oct 13, 1987Ruben HechavarriaModified compressor unit
Classifications
U.S. Classification62/77, 62/149, 62/174, 62/292
International ClassificationF25B31/00
Cooperative ClassificationF25B31/002
European ClassificationF25B31/00B