US2281770A - Defrosting system - Google Patents

Defrosting system Download PDF

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US2281770A
US2281770A US374885A US37488541A US2281770A US 2281770 A US2281770 A US 2281770A US 374885 A US374885 A US 374885A US 37488541 A US37488541 A US 37488541A US 2281770 A US2281770 A US 2281770A
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conduit
refrigerant
compressor
cooling unit
defrosting
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US374885A
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Anthony F Hoesel
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Peerless of America Inc
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Peerless of America Inc
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25BREFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B47/00Arrangements for preventing or removing deposits or corrosion, not provided for in another subclass
    • F25B47/02Defrosting cycles
    • F25B47/022Defrosting cycles hot gas defrosting
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25DREFRIGERATORS; COLD ROOMS; ICE-BOXES; COOLING OR FREEZING APPARATUS NOT OTHERWISE PROVIDED FOR
    • F25D21/00Defrosting; Preventing frosting; Removing condensed or defrost water
    • F25D21/002Defroster control
    • F25D21/008Defroster control by timer

Definitions

  • the present invention relates to hot gas defrosting of cooling units which are utilized to cool compartments to temperatures below 32 F.
  • the invention contemplates the use of the refrigerant compressor hot gas discharge in order to supply sufficient heat to the cooling unit in order to defrost-the same. It also contemplates the use of means whereby the time functioning of such defrosting system is under the adjustable control of manually operated time switch means, whereby the operator may manually initiate the various necessary functions, for the defrosting, by merely flipping a switch handle to a given time designation previously determined as being suflicient to complete the defrosting cycle. Upon the elapse of the given time, the refrigeration system then automatically resumes its previous normal operation.
  • An object, of the invention is to provide an improved system of semi-automatic hot gas defrosting of low temperature cooling units.
  • Another object, of the invention is to provide means for vaporizing, before entrance into the compressor, of the returned refrigerant fluid, which is condensed in the cooling unit due to its surrender of heat thereto.
  • FIG. 1 is a diagrammatic elevational view of a refrigerating system embodying the invention.
  • a cooling unit 2 comprised of a nested volatile refrigerant conduit circuit 3 upon which fins 4 are mounted in heat transfer relationship, is situated within a casing 5 through which, and over the exterior surfaces of the cooling unit 2, a fan 6, driven by the motor 1, forces an air circulation as indicated by the arrows.
  • the casing 5 has a drain 8, usually connected to a sewer, to get rid of the defrosted moisture during the defrosting period.
  • the refrigerant compressor 9 is driven by means of the motor I 0 and evacuates refrigerant fluid, in vapor phase, from the conduit ll.
  • the compressed vapor is forced into the discharge 'conduit I2 from whence it enters a condenser l3, wherein, during normal functioning, it surrenders its heat and becomes condensed to its liquid phase.
  • the liquid receiver I4 receives this liquid, which is then led by means of the liquid conduit l5 to an expansion valve it which tends, during normaloperation, to feed refrigerant fluid, under reduced pressure, to the refrigerant inlet conduit I! connected to the conduit circuit 3.
  • a suction conduit It serves to lead the refrigerant fluid from the outlet of the conduit circuit 3.
  • the discharge conduit [2 and the refrigerant inlet conduit ll are connected by means of the bypass conduit 2
  • the above comprises the refrigerant circulation system.
  • An electric timing switch 24 of which there are numerous suitable types commercially available at present and so well known, in the art, that in the present instance it is presumed sufficient to represent the same diagrammatically and with proper functional description, comprises a casing 25 containing clock mechanism, not shown, which is wound up by means of the timing handle 26 being moved in a clockwise direction so that the pointer 21 stops at some particular predetermined point of the graduated face, which is usually graduated in minutes of operation.
  • the timing handle 26 is shown in the stopped position. Assume it to be moved to say the 5 minute graduation, then the timing handle gradually moves counterclockwise so that at the lapse of 5 minutes the timing handle 26 is again in its present stopped position.
  • a single pole double throw switch comprised of stationary contacts 29 and 30 and a contact arm 3
  • the electrical conduits 35 and 36 leading to a suitable source of electrical energy, connect to the compressor motor ID.
  • the electrical conduit 31 connects conduit 35 with the fulcrum 32 of the contact arm 3! which is in electrical circuit therewith.
  • An electricalconduit 38 connects with the conduit 36 and one side of the coil circuit in the solenoid valve 22.
  • the other side of the coil circuit, of the solenoid valve 22, is connected to the stationary contact 30 by means of the electrical conduit 39.
  • the electrical heating element 20 is connected to the electrical conduits 3G and 39 by means of the conduits l and ll respectively.
  • the fan motor I connects to electrical conduit 38 by means of the conduit 42, and also connects to the stationary contact 29 by means of the conduit 43.
  • the above comprises the electrical wiring systern.
  • the compressor motor I 0 and the fan motor 1 are in operation.
  • the solenoid valve 22 is in closed position and the electrical heating element 20 is deenergized.
  • any returning refrigerant liquid will thereby become vaporized and the temperature of the fluid, passing through the conduit II and into the compressor 9, will be substantially the same. as that passing during normal operation. This ensures the compressor discharge fluid as being of such temperature as will do eiiicient defrosting.
  • the timing handle After the proper time lapse, depending upon the original positioning of the timing handle 26, the timing handle is automatically returned to its original position, as shown, and the contact arm 3
  • the circuit, in the conduit 43, is reestablished and the fan motor I again starts.
  • the circuit, in the conduit 39 is broken, thereby closing the solenoid valve 22 and deenergizing the electrical heating element 20.
  • a suction line conduit connected to the inlet of a compressor normally discharging compressed vapor into a conduit concharging into a refrigerant inlet conduit of the cooling unit, over the exterior surfaces of which an air circulation is maintained by a motor driven fan and upon which exterior surfaces a frost progressively accumulates
  • a by-pass conduit connected to said compressor discharge, and ahead of said condenser, and also connected to the refrigerant inlet between the said refrigerant pressure reducing means and the cooling unit
  • a normally closed solenoid valve in said by-pass conduit, electrical heating means disposed in heat transfer relationship with the refrigerant passing through the suction line conduit and normally de-energized, an electrical time switch normally maintaining a current supply to the fan motor.
  • manually operated means to set said time switch for a given time lapse during which the current suppl to said fan motor is interrupted, and during which time lapse the time switch the solenoid valve to open position allowing the compressor discharge fluid to enter the inlet of said cooling unit, said time switch, during said time lapse, also energizing said electrical heat; ing means.
  • a cooling unit normally discharging refrigerant vapor into a suction line conduit connected to the inlet of a compressor normally discharging compressed vapor into a conduitconnecting the compressor with a condenser from which a refrigerant liquid conduit leads to a refrigerant pressure reducing means normally discharging into a refrigerant inlet conduit of the cooling unit, over the exterior surfaces of which an air circulation is maintained by a motor driven fan and upon which exterior surfaces a frost progressively accumulates.

Description

y 1942- A. F. HOESEL 2,281,770
DEFROSTING SYSTEM Filed Jan. 17, 1941 &
- 2o 1 9 4l L Inventor Patented May 5, 1942 DEFBOSTING SYSTEM Anthony F. Hoesel, Chicago, 111., assignor to Peerless of America, Incorporated, Chicago, Ill.,
corporation of Illinois Application January 17, 1941, Serial No. 374,885
4 Claims. The present invention relates to hot gas defrosting of cooling units which are utilized to cool compartments to temperatures below 32 F.
More specifically the invention contemplates the use of the refrigerant compressor hot gas discharge in order to supply sufficient heat to the cooling unit in order to defrost-the same. It also contemplates the use of means whereby the time functioning of such defrosting system is under the adjustable control of manually operated time switch means, whereby the operator may manually initiate the various necessary functions, for the defrosting, by merely flipping a switch handle to a given time designation previously determined as being suflicient to complete the defrosting cycle. Upon the elapse of the given time, the refrigeration system then automatically resumes its previous normal operation.
While the use of hot compressor discharge gas, for defrosting, is rather old in the art, all previous systems necessitated manual attendance to start and stop the various necessary functions in a somewhat given sequence, and
then after the lapse of sufficient time, to then reverse the previous operations so that the system would then be in normal function.
An object, of the invention, is to provide an improved system of semi-automatic hot gas defrosting of low temperature cooling units.
Another object, of the invention, is to provide means for vaporizing, before entrance into the compressor, of the returned refrigerant fluid, which is condensed in the cooling unit due to its surrender of heat thereto.
Other objects, of the invention, will be more fully disclosed in the following specification and claims:
In the drawing, the figure is a diagrammatic elevational view of a refrigerating system embodying the invention.
Referring to the drawing, a cooling unit 2, comprised of a nested volatile refrigerant conduit circuit 3 upon which fins 4 are mounted in heat transfer relationship, is situated within a casing 5 through which, and over the exterior surfaces of the cooling unit 2, a fan 6, driven by the motor 1, forces an air circulation as indicated by the arrows.
The casing 5 has a drain 8, usually connected to a sewer, to get rid of the defrosted moisture during the defrosting period.
The refrigerant compressor 9 is driven by means of the motor I 0 and evacuates refrigerant fluid, in vapor phase, from the conduit ll.
The compressed vapor is forced into the discharge 'conduit I2 from whence it enters a condenser l3, wherein, during normal functioning, it surrenders its heat and becomes condensed to its liquid phase. The liquid receiver I4 receives this liquid, which is then led by means of the liquid conduit l5 to an expansion valve it which tends, during normaloperation, to feed refrigerant fluid, under reduced pressure, to the refrigerant inlet conduit I! connected to the conduit circuit 3. A suction conduit It serves to lead the refrigerant fluid from the outlet of the conduit circuit 3.
Interposed, between the suction conduit I8 and the conduit II, is a hollow casing I9 containing an electrical heating element 20, whose function will be described later.
The discharge conduit [2 and the refrigerant inlet conduit ll are connected by means of the bypass conduit 2| in the circuit of which is placed a solenoid valve 22.
The above comprises the refrigerant circulation system.
An electric timing switch 24, of which there are numerous suitable types commercially available at present and so well known, in the art, that in the present instance it is presumed sufficient to represent the same diagrammatically and with proper functional description, comprises a casing 25 containing clock mechanism, not shown, which is wound up by means of the timing handle 26 being moved in a clockwise direction so that the pointer 21 stops at some particular predetermined point of the graduated face, which is usually graduated in minutes of operation.
The timing handle 26 is shown in the stopped position. Assume it to be moved to say the 5 minute graduation, then the timing handle gradually moves counterclockwise so that at the lapse of 5 minutes the timing handle 26 is again in its present stopped position.
Included within the casing 25 is a single pole double throw switch comprised of stationary contacts 29 and 30 and a contact arm 3| oscillating, about the fulcrum 32, to establish an electrical circuit with either contact 29 or .30 depending upon the position of the timing handle 26.
Whenever the timing handle 26 is moved to on" position, clockwise, the contact arm 3| swings to the right and establishes contact with the stationary contact 30. This contact persists until the timing handle 26 returns to off position, as shown, at which time the contact arm 3! then swings to the left and establishes contact with the stationary contact 29, as shown.
The electrical conduits 35 and 36, leading to a suitable source of electrical energy, connect to the compressor motor ID. The electrical conduit 31 connects conduit 35 with the fulcrum 32 of the contact arm 3! which is in electrical circuit therewith.
An electricalconduit 38 connects with the conduit 36 and one side of the coil circuit in the solenoid valve 22. The other side of the coil circuit, of the solenoid valve 22, is connected to the stationary contact 30 by means of the electrical conduit 39.
The electrical heating element 20 is connected to the electrical conduits 3G and 39 by means of the conduits l and ll respectively.
The fan motor I connects to electrical conduit 38 by means of the conduit 42, and also connects to the stationary contact 29 by means of the conduit 43.
The above comprises the electrical wiring systern.
With the timing handle 26 in the off position, as shown, the compressor motor I 0 and the fan motor 1 are in operation. The solenoid valve 22 is in closed position and the electrical heating element 20 is deenergized.
During the operation of the compressor 9 and the normal circulation of refrigerant within the refrigerant conduit circuit 2, there will occur a progressive accumulation of frost upon the exterior surfaces of the conduit 3 and the fins 4 mounted thereon. After a sufficient accumulation of frost, it will then become necessary to defrost these surfaces.
The operator now moves the timing handle 26, in a clockwise direction, for some predetermined time lapse. The contact arm 3| now swingsto make contact with the stationary contact 31!. The fan motor 1 now stops and the electrical circuit is now established in both the electrical heating element 20, which now heats up, and the solenoid valve 22, which now opens.
The compressor 9, being still in operation,-
discharges hot compressed refrigerant vapor into the discharge conduit [2. Since the solenoid valve 22 is open, the hot compressed vapor passes through the conduits 2i and I! to the conduit circuit 3 in which it surrenders heat, thereby sufliclently elevating the temperature of the con-, duit 3 and flns [to defrost the same.
During this stage, the pressures in the conduit 3 become much greater than the normal, therefore no refrigerant liquid is fed through the expansion valve l6, but the hot vapor condenses within the conduit 3 and eventually passes into the suction conduit 18 in liquid phase.
It is obvious that, if liquid refrigerant passes into the compressor 9 which is conceded to be bad practice, it will among other deleterious results, naturally result in a reduced amount of work and the temperature of the discharge, to "the discharge conduit i2, will be such that it will be incapable of being an efficient defrosting agent.
Since the returned refrigerant fluid is under the influence of the heat generated by the electrical heating element 20, any returning refrigerant liquid will thereby become vaporized and the temperature of the fluid, passing through the conduit II and into the compressor 9, will be substantially the same. as that passing during normal operation. This ensures the compressor discharge fluid as being of such temperature as will do eiiicient defrosting.
After the proper time lapse, depending upon the original positioning of the timing handle 26, the timing handle is automatically returned to its original position, as shown, and the contact arm 3| swings to and makescontact with the stationary contact 29. The circuit, in the conduit 43, is reestablished and the fan motor I again starts. The circuit, in the conduit 39 is broken, thereby closing the solenoid valve 22 and deenergizing the electrical heating element 20.
The system is now in normal operation until such time as it is desired to again defrost the cooling unit. At such time, all the operator needs to do is flip the timing handle 26 to its proper time position, without giving any part of the system any further attention, since it will always automatically restore to normal function after the defrosting time lapse.
From the above, it will be noted that I have provided a defrosting system which operates with a minimum of attention and which tends to maintain a constant temperature of discharge fluid leading from the compressor.
While the drawing and specification show a particular embodiment of the invention, it is understood that various modifications may be employed without departing from the spirit and scope of the invention which is to be limited only to the claims hereto appended.
I- claim:
1. The method of defrosting a cooling unit Upon the exterior surfaces of which a progressive frost accumulation occurs during the circulation of a volatile refrigerant therethrough by means of a compressor normally evacuating refrigerant vapor from said cooling unit and discharging the compressed vapor into a condenser wherein it surrenders heat and becomes liquified prior to again normally entering said cooling unit, which comprises periodically conducting the discharge of said compressor, prior to its liquefaction in said condenser, to the cooling unit wherein it tends to surrender heat, for the defrosting function, and becomes liquified and then reheating the liquid refrigerant, issuing from said cooling unit, in order to vaporize the same before its entrance into said compressor, the said heated vapor being at substantially the same pressure as that obtaining within the cooling unit.
2. The method of defrosting a cooling unit upon the exterior surfaces of which a progressive frost accumulation occurs during the circulation of a volatile refrigerant therethrough by means of a compressor normally evacuating refrigerant vapor from said cooling unit and discharging the compressed vapor into a condenser wherein it surrenders heat and becomes liquefled prior to again normally entering said cooling unit, which comprises periodically conducting the discharge of said compressor, prior to its liquefaction in .said condenser, to the cooling unit wherein it tends to surrender heat, for the defrosting function, and becomes liquefied and then reheating the liquid refrigerant, issuing from said cooling unit, in order to vaporize the same beforeits entrance into said compressor.
3. In a mechanical refrigerating system having a cooling unit normally discharging refrigerant vapor into ,a suction line conduit connected to the inlet of a compressor normally discharging compressed vapor into a conduit concharging into a refrigerant inlet conduit of the cooling unit, over the exterior surfaces of which an air circulation is maintained by a motor driven fan and upon which exterior surfaces a frost progressively accumulates, the combination of a by-pass conduit connected to said compressor discharge, and ahead of said condenser, and also connected to the refrigerant inlet between the said refrigerant pressure reducing means and the cooling unit, a normally closed solenoid valve in said by-pass conduit, electrical heating means disposed in heat transfer relationship with the refrigerant passing through the suction line conduit and normally de-energized, an electrical time switch normally maintaining a current supply to the fan motor. manually operated means to set said time switch for a given time lapse during which the current suppl to said fan motor is interrupted, and during which time lapse the time switch the solenoid valve to open position allowing the compressor discharge fluid to enter the inlet of said cooling unit, said time switch, during said time lapse, also energizing said electrical heat; ing means.
4. In a mechanical refrigerating system having a cooling unit normally discharging refrigerant vapor into a suction line conduit connected to the inlet of a compressor normally discharging compressed vapor into a conduitconnecting the compressor with a condenser from which a refrigerant liquid conduit leads to a refrigerant pressure reducing means normally discharging into a refrigerant inlet conduit of the cooling unit, over the exterior surfaces of which an air circulation is maintained by a motor driven fan and upon which exterior surfaces a frost progressively accumulates. the combination 7 of a by-pass conduit connected to said com-- pressor discharge, and ahead of said condenser, and also connected to the refrigerant inlet between the said refrigerant pressure reducing means and the cooling unit, a normally closed solenoid valve in said by-pass conduit, electrical heating means disposed in heat transfer relationship with the refrigerant passing through the suction line conduit and normally de-energized, an electrical time switch normally maintaining a current supply to the fan motor, manually operated means to set said time switch for a given time lapse during which the current supp to said fan motor is interrupted, and during which time lapse the time switch energizes the solenoid valve to open position allowing the compressor discharge fluidto enter the inlet of said cooling unit, said time switch} during said time lapse, also energizing said electrical heating means, and the said-time switch automatically reestahlishing said fan motor current circuit and de-energizing said solenoid valve and said electrical heating means after the time lapse.
ANTHONY F. HOESEL.
US374885A 1941-01-17 1941-01-17 Defrosting system Expired - Lifetime US2281770A (en)

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Cited By (32)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2440146A (en) * 1944-11-07 1948-04-20 Kramer Trenton Co Defrosting mechanism in refrigerating apparatus
US2452102A (en) * 1944-11-06 1948-10-26 Colvin Templeton Inc Refrigerating system defrosted by hot liquid refrigerants
US2455421A (en) * 1946-06-03 1948-12-07 Advance Mfg Inc Control means for air conditioning apparatus
US2463027A (en) * 1945-03-09 1949-03-01 Kramer Trenton Co Refrigeration apparatus arranged for periodic defrosting
US2494480A (en) * 1946-04-29 1950-01-10 C V Hill & Company Inc Self-service refrigerated case having a defrosting system
US2509099A (en) * 1947-06-30 1950-05-23 U S Thermo Control Co System for controlling the operation of refrigeration units
US2522199A (en) * 1948-07-19 1950-09-12 Tyler Fixture Corp Refrigerator defrosting mechanism
US2525560A (en) * 1949-02-04 1950-10-10 Ed Friedrich Inc Low-temperature defrosting system
US2526379A (en) * 1949-03-09 1950-10-17 Gen Electric Defrosting arrangement for refrigerating systems
US2534032A (en) * 1944-08-19 1950-12-12 Kollsman Paul Refrigerator defrosting system
US2555161A (en) * 1947-06-03 1951-05-29 C V Hill & Company Inc Refrigerating system with defrosting arrangement
US2583271A (en) * 1947-12-13 1952-01-22 Harvey H Mellion Freezer defroster
US2608834A (en) * 1950-04-21 1952-09-02 Westinghouse Electric Corp Refrigerating apparatus
US2641112A (en) * 1947-08-09 1953-06-09 Muffly Glenn Refrigerator-cabinet defrosting
US2662380A (en) * 1951-02-06 1953-12-15 Frez O Mat Corp Automatic defrosting system for refrigeration machines
US2701455A (en) * 1952-07-23 1955-02-08 Dole Refrigerating Co Heated plate unit for defrosting systems
US2704924A (en) * 1951-08-15 1955-03-29 Kramer Trenton Co Refrigerating system provided with combined load balancing and reevaporating means
US2719406A (en) * 1953-04-29 1955-10-04 Seeger Refrigerator Co Refrigerator defrost systems
US2737030A (en) * 1951-12-21 1956-03-06 Nash Kelvinator Corp Refrigerating system having defrosting arrangement
US2745255A (en) * 1952-07-30 1956-05-15 American Motors Corp Defrosting refrigerating apparatus
US2800773A (en) * 1952-07-31 1957-07-30 Morris W Crew Hot gas defroster control for refrigerators
US2801523A (en) * 1952-05-15 1957-08-06 Charles C Hansen Defrosting apparatus for refrigeration systems
US2863300A (en) * 1955-10-28 1958-12-09 Gen Motors Corp Refrigerating apparatus
US2894374A (en) * 1949-02-04 1959-07-14 Muffly Glenn Defrosting control in refrigeration system
US2942432A (en) * 1950-08-09 1960-06-28 Muffly Glenn Defrosting of evaporator
US3010288A (en) * 1959-09-21 1961-11-28 Gen Motors Corp Refrigerating apparatus
US3453838A (en) * 1967-03-10 1969-07-08 Dunham Bush Inc Refrigeration system
US4176526A (en) * 1977-05-24 1979-12-04 Polycold Systems, Inc. Refrigeration system having quick defrost and re-cool
WO1982001935A1 (en) * 1980-11-26 1982-06-10 Oy Huurre A method and equipment for defrosting the vaporiser of compressor refrigeration machinery
EP0161338A1 (en) * 1984-03-23 1985-11-21 KKW Kulmbacher Klimageräte-Werk GmbH Air-water heat pump
US5065584A (en) * 1990-07-30 1991-11-19 U-Line Corporation Hot gas bypass defrosting system
WO2015062662A1 (en) * 2013-10-31 2015-05-07 Arcelik Anonim Sirketi Refrigerator with an improved defrost circuit and method for controlling the refrigerator

Cited By (32)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2534032A (en) * 1944-08-19 1950-12-12 Kollsman Paul Refrigerator defrosting system
US2452102A (en) * 1944-11-06 1948-10-26 Colvin Templeton Inc Refrigerating system defrosted by hot liquid refrigerants
US2440146A (en) * 1944-11-07 1948-04-20 Kramer Trenton Co Defrosting mechanism in refrigerating apparatus
US2463027A (en) * 1945-03-09 1949-03-01 Kramer Trenton Co Refrigeration apparatus arranged for periodic defrosting
US2494480A (en) * 1946-04-29 1950-01-10 C V Hill & Company Inc Self-service refrigerated case having a defrosting system
US2455421A (en) * 1946-06-03 1948-12-07 Advance Mfg Inc Control means for air conditioning apparatus
US2555161A (en) * 1947-06-03 1951-05-29 C V Hill & Company Inc Refrigerating system with defrosting arrangement
US2509099A (en) * 1947-06-30 1950-05-23 U S Thermo Control Co System for controlling the operation of refrigeration units
US2641112A (en) * 1947-08-09 1953-06-09 Muffly Glenn Refrigerator-cabinet defrosting
US2583271A (en) * 1947-12-13 1952-01-22 Harvey H Mellion Freezer defroster
US2522199A (en) * 1948-07-19 1950-09-12 Tyler Fixture Corp Refrigerator defrosting mechanism
US2525560A (en) * 1949-02-04 1950-10-10 Ed Friedrich Inc Low-temperature defrosting system
US2894374A (en) * 1949-02-04 1959-07-14 Muffly Glenn Defrosting control in refrigeration system
US2526379A (en) * 1949-03-09 1950-10-17 Gen Electric Defrosting arrangement for refrigerating systems
US2608834A (en) * 1950-04-21 1952-09-02 Westinghouse Electric Corp Refrigerating apparatus
US2942432A (en) * 1950-08-09 1960-06-28 Muffly Glenn Defrosting of evaporator
US2662380A (en) * 1951-02-06 1953-12-15 Frez O Mat Corp Automatic defrosting system for refrigeration machines
US2704924A (en) * 1951-08-15 1955-03-29 Kramer Trenton Co Refrigerating system provided with combined load balancing and reevaporating means
US2737030A (en) * 1951-12-21 1956-03-06 Nash Kelvinator Corp Refrigerating system having defrosting arrangement
US2801523A (en) * 1952-05-15 1957-08-06 Charles C Hansen Defrosting apparatus for refrigeration systems
US2701455A (en) * 1952-07-23 1955-02-08 Dole Refrigerating Co Heated plate unit for defrosting systems
US2745255A (en) * 1952-07-30 1956-05-15 American Motors Corp Defrosting refrigerating apparatus
US2800773A (en) * 1952-07-31 1957-07-30 Morris W Crew Hot gas defroster control for refrigerators
US2719406A (en) * 1953-04-29 1955-10-04 Seeger Refrigerator Co Refrigerator defrost systems
US2863300A (en) * 1955-10-28 1958-12-09 Gen Motors Corp Refrigerating apparatus
US3010288A (en) * 1959-09-21 1961-11-28 Gen Motors Corp Refrigerating apparatus
US3453838A (en) * 1967-03-10 1969-07-08 Dunham Bush Inc Refrigeration system
US4176526A (en) * 1977-05-24 1979-12-04 Polycold Systems, Inc. Refrigeration system having quick defrost and re-cool
WO1982001935A1 (en) * 1980-11-26 1982-06-10 Oy Huurre A method and equipment for defrosting the vaporiser of compressor refrigeration machinery
EP0161338A1 (en) * 1984-03-23 1985-11-21 KKW Kulmbacher Klimageräte-Werk GmbH Air-water heat pump
US5065584A (en) * 1990-07-30 1991-11-19 U-Line Corporation Hot gas bypass defrosting system
WO2015062662A1 (en) * 2013-10-31 2015-05-07 Arcelik Anonim Sirketi Refrigerator with an improved defrost circuit and method for controlling the refrigerator

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