US3807189A - Method of and apparatus for defrosting absorption - Google Patents

Method of and apparatus for defrosting absorption Download PDF

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Publication number
US3807189A
US3807189A US00283191A US28319172A US3807189A US 3807189 A US3807189 A US 3807189A US 00283191 A US00283191 A US 00283191A US 28319172 A US28319172 A US 28319172A US 3807189 A US3807189 A US 3807189A
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Prior art keywords
inert gas
liquid
trap
absorber
refrigerant
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US00283191A
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English (en)
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N Eber
A Asher
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Sarlab AG
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Sarlab AG
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B15/00—Sorption machines, plants or systems, operating continuously, e.g. absorption type
    • F25B15/10—Sorption machines, plants or systems, operating continuously, e.g. absorption type with inert gas
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25D—REFRIGERATORS; COLD ROOMS; ICE-BOXES; COOLING OR FREEZING APPARATUS NOT OTHERWISE PROVIDED FOR
    • F25D21/00—Defrosting; Preventing frosting; Removing condensed or defrost water
    • F25D21/06—Removing frost

Definitions

  • F25b 15/10 The structure embodies a siphon which renders it [58] Field of Search 62/490, 476, 277, 110 inoperable to block the'circulation of inert gas in its circuit responsive to accumulation of liquid above a [56] References Cited first level in the trap-and subsequently renders it UNITED STATES PATENTS operable to block the circulation of inert gas I 993 129 N19 Baird 62,110 ,X responsive to accumulation of liquid above a second 2:269:102 H1942 h 62 10 X level in the trap.
  • Absorption refrigeration apparatus of the inert gas type are often provided in which the liquid trap referred to above is absent. In such apparatus it then becomes necessary to provide such a liquid trap to flow hot refrigerant in a path of flow which by-passes the condenser. This often'impairs the desirable operating characteristics of the generator or boiler unit which is objectionable.
  • We accomplish this by providing structure including a trap having a pair of upstanding legs, one of which is connected in the inert gas circuit and the other of which is connected to receive vapor from the boiler or generator unit and condenser therein.
  • the structure embodies a siphon which renders it inoperable to block the circulation of inert gas in its circuit responsive to accumulation of condensate above a first level in the trap and subsequently renders it operable to block the circulation of inert gas responsive to accumulation of condensate above a second level in the trap.
  • the siphon functions to remove the liquid therefrom and render the structure inoperable to block the circulation of inert gas in its circuit.
  • FIG. 1 we'have shown our invention in connection with a hermetically sealed absorption refrigeration system of a uniform pressure type in which an auxiliary pressure equalizing gas is employed.
  • Aircooled systems of this type are well known and include a cooling unit or evaporator structure E which is arranged to abstract heat from the thermally insulated interior of a refrigerator cabinet 60.
  • Refrigerant fluid Refrigerant fluid
  • a suitable absorbent such as water, for example, which is introduced into coil 20 through a conduit 19.
  • the hydrogen or inert gas which is practically insoluble and weak in refrigerant, is returned to evaporator structure E in'a path of flow which includes conduit 32, the lefthand leg 37 of a U-shaped trap 36 and an elongated tube 33.
  • the elongated tube 33 forms the inner passageway 30b of the gas heat exchanger 30 and extends lengthwise within the evaporator structure E and inert gas weak in refrigerant passes from the upper open end thereof into the presence of refrigerantfluid for downward flow through the evaporator structure .E.
  • Refrigerant vapor is liquefied in the condenser 25 by surrounding cooling air which flows over the fins 24 and liquefied refrigerant is returned to the evaporator structure through the conduit 26 to complete the refrigerating cycle.
  • Liquid refrigerant flows by gravity in the evaporator structure E, the refrigerant flowing in parallel flow with the inert gas in a low temperature section 28 and then in a higher'temperature section 29 changer 62. Circulation of abosrption solution in the manner just described is due to raising of liquid to a high level in boiler pipe from which liquid can flow by gravity to the upper end of the absorber coil 20.
  • the parts of the generator or boiler G are enveloped by a body of insulation 63 retained in a shell or casing 64.
  • the outlet end of the condenser 25 is connected by a conduit'35 to the gas circuit, as at the conduit 31, for example, so that any non-condensable gas which may pass into the condenser can flow to the gas circuit and not be trapped in the condenser.
  • the refrigerator system can be controlled by a thermal bulb 65 which is affectedby a temperature condition of evaporator section 29.
  • the thermal bulb 65 is connected by a conduit 66 to a control device 67 which is connected in one of the conductors 10 for supplying electrical energy to the heating element 11.
  • the thermal bulb 65 and conduit 66 form part of an expansible fluid thermostat which is charged with a suitable vola-- tile fluid and responds to changes in a temperature condition affected by high temperature evaporator section 29 to operate control device 67 and connect and disconnect the heating element 11 to and from the source of electrical supply.
  • the refrigerating effect produced by the upper evaporator section 28, which 'is adapted to be operated 'at temperatures substantially below freezing, is primarily utilized to effect cooling of an upper freezer space which is defined by a partition 68 and the thermally insulated walls of the cabinet 60.
  • the refrigerating effect produced by the lower evaporator section 29, which is adapted to be operated at a higher temperature than that of evaporator section 28, and also desirably below freezing, is primarily utilized to cool air in an unfrozen food storage space below the partition 68.
  • the conduit 26 for conducting liquid refrigerant from condenser 26 to the evaporator structure E is heat conductively connected to both the evaporator sections 28 and 29.
  • liquid refrigerant is effectively pre-cooled before flowing into the presence of inert gas at the extreme upper end of the evaporator structure E.
  • a plurality of fins or heat transfer members 69 may be secured thereto in any suitable manner.
  • the refrigerator cabinet 60 is only diagrammatically illustrated, it will be understood that the top freezer space is provided with a separate closure member (not shown) from that provided for the unfrozen food storage space. While frost accumulates on both the evaporator sections 28 and 29, suchaccumulation of frost takes place much more slowly in the freezer space than in the unfrozen food storage space because the need for gaining access into the former is considerably less than that for the latter. When a layer of frost of considerable thickness is allowed to accumulate on the lower evaporator section 29, the efficiency of the refrigeration apparatus is reduced considerably and the apparatus operates for longer periods of time to maintain the unfrozen food storage space at a desired low temperature than otherwise would be necessary.
  • inert gas weak in refrigerant flows from the upper end of the absorber coil 20 through conduit 32 into the left-hand leg 37 of trap 36 which is connected thereto.
  • Inert gas weak in refrigerant flows from the U-shaped trap 36 to the upper end of the evaporator section 28 through the elongated tube 33, the lower end 41 of which is disposed in the left-hand leg' 37 of the trap.
  • the right-hand leg 38 of the U-shaped trap 36 is arranged to receive from the generator or boiler G vapor expelled from absorption solution therein. As shown, this is accomplished by flowing expelled vapor from the upper part 39 of boiler pipe 15 to the right-hand leg 38 of trap 36 in a path of flow which includes conduits 40 and 42. Y
  • the vapor expelled from solution in'the generator or boiler G and flowing therefrom includes refrigerant vapor and accompanying water vapor.
  • An air-cooled rectifier (not shown), which is well known, can be provided in the vapor line 23.
  • the water vapor is condensed in the rectifier and drains back to the boiler pipe 15.
  • some expelled refrigerant vapor and accompanying water vapor is diverted from the vapor line 23 into the conduits 40 and 42. Such diverted vapor diffuses slowly into the U-shaped trap 36 and continuously condensestherein.
  • the liquid level in the trap 36 continues to rise during defrosting. And the rate at which this liquid level rises can be adjusted by the dimensions selected for the conduit 42 which extends upward from the right-hand leg 38' of the trap 36 and forms a part thereof.
  • the conduit 42 extends upward a short distance from a vertical position which is more or less the same as the vertical position of the lower end 41 of the elongated tube 33.
  • the conduit 42 has a cross-sectional area which is considerably smaller than that of the remaining part of the righthand leg 38 of the trap 36.
  • a siphon 43 is connected to the left-hand leg 37 of the trap 36.
  • the highest point 44 of the siphon is [0- I cated at a suitable level above the lower end 41 of the elongated tube 33.
  • liquid is siphoned from the trap 36 through the left-hand arm of the siphon into the absorber vessel 21, thereby enabling inert gas weak in refrigerant to return from absorber coil to the evaporator structure E.
  • the liquid collected in the trap 36 essentially constitutes absorption liquid or solution which is rich in refrigerant.
  • Such liquid siphoned from the trap 36 into absorber vessel 21 flows therefrom through conduit 22 a to the pump 16 which operates at its normal operating temperature when defrosting is being effected.
  • liquid condensate formed in the condenser 25 and introduced into the evaporator structure E through the conduit 26 does not evaporate in the evaporator structure but simply flows through the evaporator sections 28 and 29, outer passage 30a of the gas heat exchanger 30 and conduit 31 into the absorber vessel 21.
  • the interval of time during which defrosting takes place can be increased or decreased by changing the relative vertical positions of the lower end 41 of the elongated tube 33 and the overflow point 44 of the siphon 43 and by increasing or decreasing the cross-sectional area of the conduit 42. Further, by changing the shape of the trap 36 and parts connected thereto, it is also possible to increase or decrease the interval of time between two successive defrosting periods.
  • FIG. 2 illustrates another embodiment of our invention in which parts similar to those shown in FIG. 1 are referred to by the same reference numerals.
  • the embodiment of FIG. 2 differs from FIG. 1 in that inert gas weak in refrigerant flows directly from the looped coil 20 to the upper end of the evaporator section 28 through a conduit 51 and elongated tube 33.
  • Inert gas rich in refrigerant flowsfrom the outer passage 30a of the gas heat exchanger 30 to the absorber vessel 21 through a conduit 50 having a U-shaped trap 52.
  • a siphon is provided for the trap 52, its short leg 53 being connected to the bottom of the trap and its long leg 55 being connected to the absorber vessel 21.
  • liquid in the trap is siphoned to the absorber vessel 21.
  • the liquidaccumulating in the U-shaped trap 52 comprises unevaporated refrigerant passing from the evaporator structure, as explained above, and absorption liquid which has condensed in the outer passage 30a of the gas heat exchanger.
  • the quantity of liquid accumulating in the U-shaped trap 52 increases slowly during normal operation of the refrigeration apparatus when the inert gas circulates in its circuit at a normal rate and is not blocked or interrupted. But when the normal circulation of inert gas is interrupted and blocked, theentire quantity of condensed refrigerant formed in the condenser 25 and introduced into the evaporator structure E flows therethrough and the gas heat exchanger 30 and conduit 50 into the U-shaped trap 52'. When this occurs the liquid level in the U- shaped trap 52 rises rapidly. 7
  • An advantage of the embodiment of FIG. 2 is that, when defrosting is being effected, absorption liquid or solution rich in refrigerant flows from the absorber vessel 21 to the pump 16, thereby maintaining the latter and the riser tube 17 at its intended operating'tempera-' ture.
  • liquid accumulated in the U-shaped trap 36 comprises condensate which flows downward in the right-hand leg 38 of the trap and also condensate which is formed inthe elongated tube 33 and flows downward in the left-hand leg 37 thereof. Since the rate at which condensate is formed in the elongated tube 33 increases and decreases with changes in the temperature of ambient air, this can adversely affect the manner in which defrosting takes place. Most important, the defrosting periods will not occur at'regular intervals of time. In order to overcome this disadvantage which is present in the embodiment of FIG. 1, we have provided another embodiment of our invention which is illustrated in FIG. 3 and in which parts similar to those shown in FIG. 1 are referred to by the samereference numerals.
  • a conduit or tube 58 which is connected at 58 to the extension 57, includes a horizontally extending part 58a inclined downward to the connecting point 58 and a vertical part 58! extending downward in the left-hand leg 37 of the U-shaped trap 36.
  • the vertical part 58b of the conduit or tube 58 corresponds to the lower end 41 of the elongated tube 33 in FIG. 1 and that the circulation of inert gas in its circuit will be blocked by liquid inthe same manner in FIG. 3 as in FIG. 1.
  • any condensate formed in the elongated tube 33 in FIG. 3 cannot flow to the U-shaped trap 36 but instead will flow downward through the extension 57 into the absorber vessel 21.
  • FIG. 4 A further embodiment of the invention is illustrated in FIG. 4, in which parts similar to those shown in FIG. 3 are referred to by the same reference numerals.
  • FIG. 4 the upper end of the absorber through a conduit 70 is connected to the elongated inner tube 33 of the gas heat exchanger 30'. Inert gas weak in refrigerant'passes this way from the absorber 20 to the evaporator section 28.
  • the inert gas rich in refrigerant vapor coming from the evaporator sections 28 and 29 through the gas heat exchanger 30' is conducted through conduit 71 to the left-hand leg 37 of the U-shaped trap 36.
  • the rich gas flows into the lower end 41 of a conduit 72, the other end o f which is connected to the absorber vessel 21 above the liquid therein so that the gas can flow into the lower end of the absorber 20.
  • extension 57 of the elongated tube 33 extends into the absorber vessel 21 below the liquid surface level therein. So does also an extension 73 of the outer conduit of the gas heat exchanger 30".
  • Absorption refrigeration apparatus of the inert gas type comprising a. interconnected parts including b. a gas circuit having a cooling element in which liquid refrigerantevaporates in the presence of inert gas to produce a refrigerating effect,
  • said means being rendered operable to block circulation of inert gas in its circuit responsive to the liquid therein reaching the second level
  • said blocking means embodying provisions for transferring liquid therefrom to another part of the apparatus responsive to the liquid therein reaching the third level.
  • Absorption refrigeration apparatus as set forth in claim 5 in which I a. said means for blocking circulation of inert gas comprises a trap having a pair of upstanding. legs arranged to collect the liquid, and
  • said inert gas circuit including at least one leg of said trap
  • said trap being rendered operable to block circulation of inert gas in its circuit responsive to the liquid therein reaching the second level.
  • said gas circuit includes an absorber and a vessel connected to receive liquid from said absorber, the outlet of said siphon being connected to discharge liquid to said vessel.
  • said gas circuit includes an absorber, first conduit means for flowing inert gas weak in refrigerant from said absorber to said cooling element and second conduit means for flowing inert gas rich in refrigerant from said cooling element to said absorber,
  • said means for blocking circulation of inert gas being constructed and arranged to block the circulation of inert gas in said first conduit means.
  • Absorption refrigeration apparatus as set forth in claim 9 in which a a. said absorber includes an absorber vessel connected to receive liquid from said absorber,
  • said cooling element comprising an elongated hollow member and one section of said first conduit means including piping extending lengthwise within said hollow member,
  • Absorption refrigeration apparatus as set forth in claim in which a. said gas circuit includes said cooling element and an absorber, first conduit means for flowing inert gas weak in refrigerant from said absorber to said cooling element and second conduit means for flowing inert gas rich in refrigerant from said cooling element to said absorber,
  • c. means including a vapor line and a condenser interconnecting said vapor expulsion unit and said cooling element,
  • said means for blocking circulation of inert gas comprising a trap having a pair of upstanding legs, one of said legs forming a part of said first conduit means of said gas circuit and the other of said legs being connected to receive vapor from said vapor expulsion unit, and
  • said first conduit means of said gas circuit including piping depending downward in said one leg of said trap and having the lower open end thereof below the level to which liquid can rise in said one leg.
  • Absorption refrigeration apparatus as set forth in claim 11 in which the other of said legs of said trap connected to receive vapor from said vapor expulsion unit, in an upward direction from a region at substantially the same level as the lower open end of said piping, has a cross-sectional area smaller than that of other parts of said trap.
  • Absorption refrigeration apparatus as set forth in claim 5 in which a. said gas circuit includes an absorber, first conduit means for flowing inert gas weak in refrigerant from said absorber to said cooling element and second conduit means for flowing inert gas rich in refrigerant from said cooling element to said absorber,
  • said means for blocking circulation of inert gas being constructed and arranged to block the 'circulation of inert gas in said second conduit means.
  • Absorption refrigeration apparatus as set forth in claim 13 in which a. said absorber includes an absorber vessel connected to receive liquid from said absorber,
  • said means for blocking circulation 'of inert gas comprising a trap in said second conduit means
  • Absorption refrigeration apparatus as set forth in claim 14 in which the discharge end of said siphon is connected to said absorber vessel.
  • Absorption refrigeration apparatus as set forth in claim 5 which includes a. a condenser for liquefying refrigerant vapor and a conduit for conducting liquid refrigerant from said condenser to said cooling element, Y

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Mechanical Engineering (AREA)
  • Thermal Sciences (AREA)
  • General Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Sorption Type Refrigeration Machines (AREA)
  • Defrosting Systems (AREA)
  • Devices That Are Associated With Refrigeration Equipment (AREA)
US00283191A 1971-09-03 1972-08-23 Method of and apparatus for defrosting absorption Expired - Lifetime US3807189A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
SE11229/71A SE355407B (enrdf_load_stackoverflow) 1971-09-03 1971-09-03

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US3807189A true US3807189A (en) 1974-04-30

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US00283191A Expired - Lifetime US3807189A (en) 1971-09-03 1972-08-23 Method of and apparatus for defrosting absorption

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US (1) US3807189A (enrdf_load_stackoverflow)
JP (1) JPS5631491B2 (enrdf_load_stackoverflow)
AR (1) AR193666A1 (enrdf_load_stackoverflow)
AU (1) AU469316B2 (enrdf_load_stackoverflow)
BR (1) BR7205939D0 (enrdf_load_stackoverflow)
CH (1) CH546933A (enrdf_load_stackoverflow)
GB (1) GB1368186A (enrdf_load_stackoverflow)
HU (1) HU168857B (enrdf_load_stackoverflow)
IL (1) IL40187A (enrdf_load_stackoverflow)
PH (1) PH9786A (enrdf_load_stackoverflow)
SE (1) SE355407B (enrdf_load_stackoverflow)
ZA (1) ZA725737B (enrdf_load_stackoverflow)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3874193A (en) * 1973-03-02 1975-04-01 Electrolux Ab Absorption refrigerator with additional means for defrosting the refrigerator
US5729996A (en) * 1996-07-11 1998-03-24 Norcold, Inc. Vented drip tray for gas absorption refrigerators
US5865039A (en) * 1995-05-05 1999-02-02 Electrolux Siegen Gmbh Method for operating an absorption refrigeration unit as well as an absorption refrigeration unit
US8707716B1 (en) * 2011-12-14 2014-04-29 The Boeing Company Re-circulating defrosting heat exchanger

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS51115715A (en) * 1975-04-04 1976-10-12 Hitachi Ltd Signal transmitting and receiving coil
JP2691164B2 (ja) * 1993-09-24 1997-12-17 エノ産業株式会社 原木自動樹皮剥ぎ装置
KR102031615B1 (ko) 2017-03-28 2019-10-15 티디케이가부시기가이샤 자성 코어용 연자성 박대, 자성 코어, 코일 유닛 및 와이어리스 전력 전송 유닛

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1993129A (en) * 1932-07-19 1935-03-05 William F Baird Autodefrosting refrigeration apparatus
US2269102A (en) * 1938-02-19 1942-01-06 Servel Inc Refrigeration
US2468104A (en) * 1945-05-02 1949-04-26 Servel Inc Absorption refrigeration system, including defrosting apparatus and method
US3063257A (en) * 1959-11-13 1962-11-13 Whirlpool Co Defrosting apparatus for an absorption refrigerator
US3177675A (en) * 1961-03-20 1965-04-13 Electrolux Ab Defrosting arrangement and control for refrigeration apparatus
US3580004A (en) * 1967-11-17 1971-05-25 Electrolux Ab Apparatus for defrosting cooling units of absorption refrigeration systems
US3678699A (en) * 1969-09-29 1972-07-25 Electrolux Ab Absorption

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CH376530A (de) * 1959-07-10 1964-04-15 Stierlin Hans Verfahren und Einrichtung zum Abtauen des Verdampfers eines Absorptionskühlschrankes

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1993129A (en) * 1932-07-19 1935-03-05 William F Baird Autodefrosting refrigeration apparatus
US2269102A (en) * 1938-02-19 1942-01-06 Servel Inc Refrigeration
US2468104A (en) * 1945-05-02 1949-04-26 Servel Inc Absorption refrigeration system, including defrosting apparatus and method
US3063257A (en) * 1959-11-13 1962-11-13 Whirlpool Co Defrosting apparatus for an absorption refrigerator
US3177675A (en) * 1961-03-20 1965-04-13 Electrolux Ab Defrosting arrangement and control for refrigeration apparatus
US3580004A (en) * 1967-11-17 1971-05-25 Electrolux Ab Apparatus for defrosting cooling units of absorption refrigeration systems
US3678699A (en) * 1969-09-29 1972-07-25 Electrolux Ab Absorption

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3874193A (en) * 1973-03-02 1975-04-01 Electrolux Ab Absorption refrigerator with additional means for defrosting the refrigerator
US5865039A (en) * 1995-05-05 1999-02-02 Electrolux Siegen Gmbh Method for operating an absorption refrigeration unit as well as an absorption refrigeration unit
US5729996A (en) * 1996-07-11 1998-03-24 Norcold, Inc. Vented drip tray for gas absorption refrigerators
US8707716B1 (en) * 2011-12-14 2014-04-29 The Boeing Company Re-circulating defrosting heat exchanger

Also Published As

Publication number Publication date
PH9786A (en) 1976-03-17
IL40187A (en) 1975-04-25
AR193666A1 (es) 1973-05-11
JPS4836749A (enrdf_load_stackoverflow) 1973-05-30
JPS5631491B2 (enrdf_load_stackoverflow) 1981-07-22
BR7205939D0 (pt) 1973-07-17
HU168857B (enrdf_load_stackoverflow) 1976-07-28
AU469316B2 (en) 1976-02-12
AU4628772A (en) 1974-03-14
GB1368186A (en) 1974-09-25
DE2242342A1 (de) 1973-03-15
CH546933A (de) 1974-03-15
ZA725737B (en) 1973-05-30
SE355407B (enrdf_load_stackoverflow) 1973-04-16
DE2242342B2 (de) 1976-04-29
IL40187A0 (en) 1972-10-29

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