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US3839878A - Apparatus for controlling refrigerator defrost apparatus - Google Patents

Apparatus for controlling refrigerator defrost apparatus Download PDF

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Publication number
US3839878A
US3839878A US00316912A US31691272A US3839878A US 3839878 A US3839878 A US 3839878A US 00316912 A US00316912 A US 00316912A US 31691272 A US31691272 A US 31691272A US 3839878 A US3839878 A US 3839878A
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US
United States
Prior art keywords
temperature
defrost
refrigerator
predetermined value
temperatures
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US00316912A
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English (en)
Inventor
A Tilmanis
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Whirlpool International BV
Original Assignee
US Philips Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from AU48079/72A external-priority patent/AU459546B2/en
Application filed by US Philips Corp filed Critical US Philips Corp
Application granted granted Critical
Publication of US3839878A publication Critical patent/US3839878A/en
Assigned to WHIRLPOOL INTERNATIONAL B.V. reassignment WHIRLPOOL INTERNATIONAL B.V. ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: U. S. PHILIPS CORPORATION, A DE CORP.
Anticipated expiration legal-status Critical
Assigned to WHIRLPOOL INTERNATIONAL B.V. reassignment WHIRLPOOL INTERNATIONAL B.V. ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: U. S. PHILIPS CORPORATION
Expired - Lifetime legal-status Critical Current

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Classifications

    • 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
    • F25D21/002—Defroster control
    • F25D21/006—Defroster control with electronic control circuits
    • 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
    • F25B2700/00—Sensing or detecting of parameters; Sensors therefor
    • F25B2700/21—Temperatures
    • F25B2700/2117—Temperatures of an evaporator
    • 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
    • F25D2400/00—General features of, or devices for refrigerators, cold rooms, ice-boxes, or for cooling or freezing apparatus not covered by any other subclass
    • F25D2400/04—Refrigerators with a horizontal mullion
    • 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
    • F25D2700/00—Means for sensing or measuring; Sensors therefor
    • F25D2700/12—Sensors measuring the inside temperature
    • F25D2700/122—Sensors measuring the inside temperature of freezer compartments

Definitions

  • F25 d 21/06 monitor the temperature of the evaporator coil and [58] Field of Search 62/80, 208 213 156 the storage space. When the difference in these temperatures exceeds a predetermined value, and one of [56] References Cited the monitored temperatures is less than a predeter- UNITED STATES PATENTS mined value, the defrost operation will be initiated. 2,7l9,406 10/1955 Tobey...l 62/155 4 c'iaifii's'fi'brawnig' 91556;
  • This invention relates to automatic defrosting systems for refrigerators, especially domestic and food display refrigerators, but is not limited thereto.
  • Automatic defrosting apparatus of the kind at present in common use operates on a fixed time cycle so that defrosting occurs at fixed time intervals.
  • the build-up of frost on the evaporator is quite variable as it depends upon many factors including, among others, the ambient air temperature, ambient air humidity, the frequency with which the refrigerator door is opened and the nature of the goods stored in the refrigerator chamber.
  • a defrosting system which operates on a fixed time cycle is generally inefficient as the fixed interval between successive operations may be either too short or too long according to the particular conditions obtaining.
  • the fixed time interval is the shortest time likely to be required so that, in most cases, defrosting occurs more often than is necessary and this involves excessive expenditure of power and higher food keeping temperatures because the waste heat absorbed within the refrigerator during each defrost cycle must be removed during the next succeeding refrigeration cycle.
  • Such a control system is subject to the disadvantage that in some circumstances, e.g., when the ambient temperature is low and the refrigerator is only lightly loaded, the evaporator coil temperature may fall to the predetermined low temperature while the temperature in the storage compartment is still sufficiently low and possibly at an optimum value. In such circumstances, an unnecessary defrost cycle would be initiated with consequent wastage of power, and an unnecessary increase would occur in the temperature of the stored food or other material.
  • the temperature of the evaporator coil may never fall to the predetermined value required to initiate a defrost cycle. In such a situation, the system would eventually fail due to excessive build-up of frost.
  • the present invention broadly provides the method of controlling the operation of refrigerator defrost apparatus comprising continuously or periodically sensing the temperature of, or closely adjacent to, the evaporator coil and the temperature of a storage space of the refrigerator, and automatically initiating operation of said defrost apparatus when the difference between said two temperatures exceeds a predetermined value and, a selected one of said two temperatures is less than a predetermined temperature.
  • the said storage space may be a freezing chamber or a refrigerator chamber so that in a typical refrigerator of the so-called two-temperature type, the said temperature sensing means for'the storage space may be located in or near either the freezing chamber or the refrigerated chamber thereof.
  • this temperature sensing means is arranged in the path of circulated air shortly after it has passed over the evaporator coil so that in the case of a two-temperature refrigerator, it is advantageously arranged at or near the position at which the cold air entersthe freezing chamber.
  • the invention also provides apparatus for the aforesaid purpose comprising means for continuously or pe riodically sensing the temperature of, or closely adjacent to, the evaporator coil of the refrigerator, means for continuously or periodically sensing the temperature of a storage space of the refrigerator, and means controlled by saidtemperature sensing means for initi ating operation of said defrost apparatus when, the difference between said two temperatures exceeds a predetermined value and, a selected one of said temperatures is less than a predetermined temperature.
  • the duration of operation of the defrost apparatus is controlled by timing means in the known manner, that is to say, the defrost cycle is of uniform duration, though the invention is not limited thereto as alternatively, means also of aknown kind may be used to terminate the defrost cycle and restart the compressor when the temperature in the storage compartment rises to a predetermined value, or the evaporator is fully defrosted.
  • frost builds up on the evaporator coil, it exercises a progressively increasing insulating effect, so that eventually the rate of heat inflow to the storage space exceeds the rate at which heat is extracted therefrom by the evaporator. In such circumstances, the temperature of the evaporator coil progressively falls while the temperature of the storage space progressively increases, so that, for both reasons, the difference between these temperatures progressively increases.
  • the temperature sensing means for the evaporator coil is preferably mounted in contact with the coil, it may alternatively be mounted out of contact therewith but in such close proximity thereto, that during each refrigeration cycle, said sensing means is progressively covered by the layer of frost which accumulates on the coil and is thus insulated thereby from the circulated air.
  • This temperature difference therefore may be utilised to effect the start of a defrost cycle when the difference rises to a predetermined value.
  • the temperatures of both the storage chamber and the evaporator coil may both be initially at or aboutthe ambient temperature, and in such circumstances, the temperature of the evaporator coil is normally reduced more rapidly than that of the storage chamber so that the said predetermined temperature difference may be reached while the temperature of the storage chamber is still relatively high.
  • a defrosting cycle could occur during the starting-up operation when it is not only not required, but is undesirable.
  • a further necessary condition for initiating a defrost cycle is that the temperature of either the evaporator coil or the storage space, and preferably the latter, is less than a predetermined temperature.
  • the temperature sensing means may be of any convenient type, e.g., thermistors or thermal bulbs, and any appropriate means controlled thereby may be provided for initiating a defrost cycle when the predetermined control conditions are satisfied.
  • the said apparatus preferably comprises an electrical control circuit having two switches connected in series with means operable, when the circuit is completed by the closure of both switches, to initiate a defrost cycle.
  • the said apparatus also includes means controlled by a sensor for the temperature of either the evaporator coil or the storage space for turning on one of said switches when the respective temperature falls below a predetermined temperature and vice versa, and means controlled by a sensor for the temperature of the storage space and by a sensor for the temperature of the evaporator coil for turning the other said switch when the difference between such temperatures exceeds a predetermined temperature and vice versa. Consequently, during the defrost cycle, the lastmentioned switch at least, is automatically turned off as the temperature differential between the evaporator coil and the storage space, progressively decreases.
  • each of said temperature sensors is a thermistor and each of said switches is preferably an electronic switch to one of which both thermistors are connected, while one of the thermistors is connected to the other switch.
  • potentials which correspond respectively to the temperature of the evaporator coil and to the temperature of the storage space are continuously applied to one of said switches which is adjusted so as to switch its output from the position to l position when the temperature difference increases to the aforesaid predetermined value.
  • the potential of one of the said thermistors, or of a further thermistor arranged preferably in the storage compartment, is connected to the second electronic switch and when the temperature of this thermistor falls below a predetermined value, this second switch switches to its 1 position.
  • FIG. 1 is a diagram showing in side elevation certain parts of a typical domestic refrigerator
  • FIG. 2 is a diagram of one defrost control circuit according to the invention.
  • the refrigerator diagrammatically shown therein comprises an outer case 10, a frozen food storage chamber 12 and a refrigerated food storage chamber 14, each of these chambers being normally closed at the front by a door.
  • the refrigeration system is conventional and includes a sealed refrigerating unit 16, comprising an electric motor and a compressor, an evaporator 18 arranged adjacent to frozen food chamber 12, a condenser 20 and a fan 22 operated in unison with the compressor to circulate the cold air.
  • the illustrated refrigerator also includes defrosting means of a conventional kind including a defrost timer 24.
  • This timer when actuated, opens switches to effect de-energisation of the sealed unit 16 and fan 22 for a pre-set time interval and also causes the heater 26 to be energized until its circuit is interrupted by the thermostat 28 when the temperature of the evaporator rises to a predetermined value, all in the usual manner.
  • this invention is concerned with the method of, and means for, starting a defrost cycle and in the illustrated apparatus this is achieved by closing a starting switch (not shown) for the timer 24.
  • the starting switch is controlled by two thermistors 36 and 38 which are connected by conductors 37 and 39 respectively, to electronic control means diagrammatically indicated at 34 in the figure.
  • These thermistors are of the negative temperature coefficient (NTC) type so that they develop potentials which increase as their respective temperatures decrease.
  • the thermistor 36 is arranged in contact with the coil of the evaporator 18 while the thermistor 38 is arranged withinthe frozen food storage chamber 12.
  • FIG. 2 One suitable control circuit is shown in FIG. 2, in which the thermistor 36 is connected in series with a resistance 40 between leads 42 and 43 from the output of a power transformer 44, the lead 42 having a diode 45 and a resistance 46 arranged in series therewith while a zener diode 47 is connected across the leads in parallel with condenser 48 to stabilize the voltage applied to the thermistors.
  • the other thermistor 38 is similarly arranged in series with a resistance 49 between the leads 42 and 43.
  • the thermistor 36 is connected by conductor 50 to an integrated circuit forming an electronic switch 52 while the thermistor 38 is similarly connected by conductor 54 to the same switch and is also connected by conductor 55 to a second electronic switch 56.
  • a relay driver 60 e.g., a silicon controlled rectifier, connected between the leads 42 and 43 in series with a relay winding RL and a normally closed switch 28 controlled by a thermostat responsive to the temperature of the evaporator 18.
  • the switch 52 is arranged to switch to its 1 rail or condition when the temperature difference between the thermistors 38 and 36 exceeds a predetermined value, and vice versa, while the switch 56 switches to its 1 rail or condition when the temperature of the thermistor 38 is less than a predetermined value.
  • the relay driver is activated whereby the circuit of relay winding RL is completed and this relay operates to close the aforesaid starter switch for the timer 24.
  • the switch 52 switches back to its 0 rail or condition during the defrost cycle and generally the switch 56 also returns to its 0 condition.
  • the relay RL when operated, remains energised until the thermostat switch 28 automatically opens consequent upon the increasing temperature of the evaporator.
  • De-energisation of the relay RL does not cause the timer to be de-energised as the latter includes a by-pass switch which is automatically closed when the timer commences to operate and which remains closed until the pre-set time cycle is completed when the compressor motor and fan are automatically restarted.
  • the invention provides an improved method of and apparatus for automatically controlling refrigerator defrost apparatus so that defrosting occurs only when this is required due to excessive frost build-up and not, as is usual, at fixed time intervals.
  • the defrost control is directly responsive to the particular thermal conditions which are indicative of a need for defrosting as contrasted with the known demand system which operates when the evaporator temperature falls to a predetermined value and with a known indirect method which involves sensing variations in air flow consequent upon frost build-up.
  • Apparatus for controlling the operation of refrigerator defrost apparatus comprising, means for continuously sensing the temperature of the evaporator coil of the refrigerator, means for continuously sensing the temperature of a storage space of the refrigerator, and means controlled by said temperature sensing means for initiating operation of said defrost apparatus when the difference between said two temperatures exceeds a predetermined value and, a selected one of said temperatures is less than a predetermined temperature
  • said means for initiating defrost including an electrical control circuit comprising two normally turned off electronic switches arranged in series with means operable, when energized to initiate operation of said defrost apparatus, and including means responsive to said two temperature sensing means to cause one of said electronic switches to turn on when the difference between the two temperatures sensed thereby exceeds said predetermined value, and vice versa, and means responsive to a selected one of said temperature sensing means to cause the other said electronic switch to turn on when the temperature sensed thereby is less than the said predetermined temperature, and vice versa.
  • said automatic defrost apparatus comprises timing means which determine the duration of operation of the defrost apparatus.
  • Apparatus according to claim 1 including means responsive to the temperature of a storage space of the refrigerator for terminating operation of the defrost apparatus when the temperature of the storage space rises to apredetermined value.
  • each of said temperature sensing means is a thermistor.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Physics & Mathematics (AREA)
  • Mechanical Engineering (AREA)
  • Thermal Sciences (AREA)
  • General Engineering & Computer Science (AREA)
  • Defrosting Systems (AREA)
US00316912A 1971-12-23 1972-12-20 Apparatus for controlling refrigerator defrost apparatus Expired - Lifetime US3839878A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
AUPA749471 1971-12-23
AU48079/72A AU459546B2 (en) 1972-10-23 1972-10-23 Method of and apparatus for controlling refrigerator defrost apparatus

Publications (1)

Publication Number Publication Date
US3839878A true US3839878A (en) 1974-10-08

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Application Number Title Priority Date Filing Date
US00316912A Expired - Lifetime US3839878A (en) 1971-12-23 1972-12-20 Apparatus for controlling refrigerator defrost apparatus

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US (1) US3839878A (es)
JP (1) JPS4870939A (es)
DE (1) DE2262039B2 (es)
ES (1) ES409911A1 (es)
FR (1) FR2164789B1 (es)
GB (1) GB1404210A (es)
IT (1) IT976129B (es)

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4086780A (en) * 1975-09-09 1978-05-02 Bosch-Siemens Hausgerate Gmbh Refrigerating apparatus, in particular two-temperature refrigerator
US4142374A (en) * 1977-09-16 1979-03-06 Wylain, Inc. Demand defrost time clock control circuit
US4790143A (en) * 1987-10-23 1988-12-13 Thermo King Corporation Method and apparatus for monitoring a transport refrigeration system and its conditioned load
US4843833A (en) * 1984-03-06 1989-07-04 Trw Canada Limited Appliance control system
US4903500A (en) * 1989-06-12 1990-02-27 Thermo King Corporation Methods and apparatus for detecting the need to defrost an evaporator coil
DE4400634A1 (de) * 1994-01-12 1995-07-13 Licentia Gmbh Kühlgerät mit beheizbarem Verdampfer
US5460010A (en) * 1993-02-23 1995-10-24 Sanyo Electric Co., Ltd. Refrigerator
US5666816A (en) * 1994-11-30 1997-09-16 Samsung Electronics Co., Ltd. Defrosting method and apparatus for refrigerator using GA-fuzzy theory
US6205800B1 (en) * 1999-05-12 2001-03-27 Carrier Corporation Microprocessor controlled demand defrost for a cooled enclosure
US6606870B2 (en) 2001-01-05 2003-08-19 General Electric Company Deterministic refrigerator defrost method and apparatus
US20040244389A1 (en) * 2003-06-09 2004-12-09 Denvir Kerry J. Integrated refrigeration control
US20060242973A1 (en) * 2003-04-04 2006-11-02 Bsh Bosch Und Siemens Hausgerate Gmbh Refrigeration device and operating method for the same
US20070006600A1 (en) * 2003-04-04 2007-01-11 Bsh Bosch Und Siemens Hausgeråte Gmbh Refrigeration device with adaptive automatic defrosting and corresponding defrosting method
US20080196424A1 (en) * 2007-02-20 2008-08-21 Behr America, Inc. Rear evaporator core freeze protection method

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5151035A (en) * 1974-10-30 1976-05-06 Mitsubishi Electric Corp Reizokono chakusokenchikairo
JPS5195643A (en) * 1975-02-20 1976-08-21 Reikyakukino chakusokenchikairo
DE2616175A1 (de) * 1976-04-13 1977-10-27 Bosch Siemens Hausgeraete Kuehlgeraet, insbesondere haushaltskuehlschrank o.dgl.
IT1155313B (it) * 1982-04-20 1987-01-28 Indesit Dispositivo di sbrinamento per un apparecchio frigorifero
FR2538518B1 (fr) * 1982-12-22 1986-04-04 Elf Aquitaine Procede et dispositif de surveillance et de commande d'un evaporateur
GB2133867B (en) * 1983-01-21 1986-06-11 Newtech Controls Ltd Defrost control means
GB2456744A (en) * 2007-08-30 2009-07-29 Ebac Ltd Auto-defrost refrigeration apparatus

Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2719406A (en) * 1953-04-29 1955-10-04 Seeger Refrigerator Co Refrigerator defrost systems
US2994209A (en) * 1959-02-26 1961-08-01 Gen Motors Corp Frostless refrigerator
US3018637A (en) * 1960-02-17 1962-01-30 Gen Motors Corp Refrigerator with defrost means
US3029611A (en) * 1959-11-16 1962-04-17 Gen Motors Corp Refrigerating apparatus with defrosting means
US3063250A (en) * 1960-08-19 1962-11-13 Gen Motors Corp Refrigeration apparatus with defrost control means
US3222882A (en) * 1964-01-17 1965-12-14 Texas Instruments Inc Refrigeration temperature and frost control
US3277662A (en) * 1965-02-23 1966-10-11 Westinghouse Electric Corp Refrigeration system defrost control
US3363429A (en) * 1966-03-11 1968-01-16 Motorola Inc Temperature control circuit for refrigeration system
US3474638A (en) * 1968-03-25 1969-10-28 Gen Electric Electronic refrigeration system defrost control
US3553975A (en) * 1967-08-07 1971-01-12 Sanyo Electric Co Refrigerator temperature and defrosting control
US3681933A (en) * 1970-08-20 1972-08-08 Dynamics Corp America Defrost control

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2669848A (en) * 1952-10-21 1954-02-23 Fujii Minoru Automatic refrigerating defrosting control
FR1450981A (fr) * 1965-10-21 1966-06-24 Texas Instruments Inc Dispositif de réglage pour appareil de réfrigération
CA844775A (en) * 1967-11-09 1970-06-16 H. Ting Youn Defrost control apparatus

Patent Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2719406A (en) * 1953-04-29 1955-10-04 Seeger Refrigerator Co Refrigerator defrost systems
US2994209A (en) * 1959-02-26 1961-08-01 Gen Motors Corp Frostless refrigerator
US3029611A (en) * 1959-11-16 1962-04-17 Gen Motors Corp Refrigerating apparatus with defrosting means
US3018637A (en) * 1960-02-17 1962-01-30 Gen Motors Corp Refrigerator with defrost means
US3063250A (en) * 1960-08-19 1962-11-13 Gen Motors Corp Refrigeration apparatus with defrost control means
US3222882A (en) * 1964-01-17 1965-12-14 Texas Instruments Inc Refrigeration temperature and frost control
US3277662A (en) * 1965-02-23 1966-10-11 Westinghouse Electric Corp Refrigeration system defrost control
US3363429A (en) * 1966-03-11 1968-01-16 Motorola Inc Temperature control circuit for refrigeration system
US3553975A (en) * 1967-08-07 1971-01-12 Sanyo Electric Co Refrigerator temperature and defrosting control
US3474638A (en) * 1968-03-25 1969-10-28 Gen Electric Electronic refrigeration system defrost control
US3681933A (en) * 1970-08-20 1972-08-08 Dynamics Corp America Defrost control

Cited By (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4086780A (en) * 1975-09-09 1978-05-02 Bosch-Siemens Hausgerate Gmbh Refrigerating apparatus, in particular two-temperature refrigerator
US4142374A (en) * 1977-09-16 1979-03-06 Wylain, Inc. Demand defrost time clock control circuit
US4843833A (en) * 1984-03-06 1989-07-04 Trw Canada Limited Appliance control system
US4879878A (en) * 1984-03-06 1989-11-14 Trw Canada, Ltd. Air damper assembly for refrigerator/freezer
US4790143A (en) * 1987-10-23 1988-12-13 Thermo King Corporation Method and apparatus for monitoring a transport refrigeration system and its conditioned load
US4903500A (en) * 1989-06-12 1990-02-27 Thermo King Corporation Methods and apparatus for detecting the need to defrost an evaporator coil
US5460010A (en) * 1993-02-23 1995-10-24 Sanyo Electric Co., Ltd. Refrigerator
DE4400634A1 (de) * 1994-01-12 1995-07-13 Licentia Gmbh Kühlgerät mit beheizbarem Verdampfer
US5666816A (en) * 1994-11-30 1997-09-16 Samsung Electronics Co., Ltd. Defrosting method and apparatus for refrigerator using GA-fuzzy theory
US6205800B1 (en) * 1999-05-12 2001-03-27 Carrier Corporation Microprocessor controlled demand defrost for a cooled enclosure
KR100455873B1 (ko) * 1999-05-12 2004-11-06 캐리어 코포레이션 냉각 수납부용 마이크로프로세서 제어식 주문형 제상
US6606870B2 (en) 2001-01-05 2003-08-19 General Electric Company Deterministic refrigerator defrost method and apparatus
US20060242973A1 (en) * 2003-04-04 2006-11-02 Bsh Bosch Und Siemens Hausgerate Gmbh Refrigeration device and operating method for the same
US20070006600A1 (en) * 2003-04-04 2007-01-11 Bsh Bosch Und Siemens Hausgeråte Gmbh Refrigeration device with adaptive automatic defrosting and corresponding defrosting method
US20040244389A1 (en) * 2003-06-09 2004-12-09 Denvir Kerry J. Integrated refrigeration control
US6851270B2 (en) * 2003-06-09 2005-02-08 Texas Instruments Incorporated Integrated refrigeration control
US20080196424A1 (en) * 2007-02-20 2008-08-21 Behr America, Inc. Rear evaporator core freeze protection method

Also Published As

Publication number Publication date
GB1404210A (en) 1975-08-28
IT976129B (it) 1974-08-20
FR2164789B1 (es) 1977-04-08
ES409911A1 (es) 1976-07-01
JPS4870939A (es) 1973-09-26
DE2262039A1 (de) 1973-07-05
FR2164789A1 (es) 1973-08-03
DE2262039B2 (de) 1980-01-17

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Date Code Title Description
AS Assignment

Owner name: WHIRLPOOL INTERNATIONAL B.V., TARWELAAN 58, 5632 K

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:U. S. PHILIPS CORPORATION, A DE CORP.;REEL/FRAME:005591/0657

Effective date: 19901113

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Owner name: WHIRLPOOL INTERNATIONAL B.V.

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:U. S. PHILIPS CORPORATION;REEL/FRAME:005978/0607

Effective date: 19901113

Owner name: WHIRLPOOL INTERNATIONAL B.V., NETHERLANDS

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:U. S. PHILIPS CORPORATION;REEL/FRAME:005978/0607

Effective date: 19901113