US3633374A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Refrigerator with self-regulating heaters
Assignee: Motors Liquidation Co
•
Filing: 1970-02-06
•
Granted: 1972-01-11
•
Expires: 1990-02-06
Abstract
Abstract In the preferred form a refrigerator is provided with positive temperature coefficient thermistors acting either as heaters alone or in series with a small electric heater for preventing condensation of moisture adjacent the door openings and for evaporating melted frost and also to prevent freezing of the water delivery means of the icemaker provided in the refrigerator as well as preventing freezing of defrost water in the drainage means or the evaporator and to control the heating temperature of the butter compartment to maintain the butter at proper spreading consistency, and to heat the fluid motor of the control switch to assure control in accordance with the temperature of the thermosensitive element.
Inventors
- 👤 James A Canter
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 23:18
CPC Classifications
F; F25; F25D; F25D11/00; F25D11/02; F25C; F25C1/00; F25C1/22; F25C1/25; F25D17/00; F25D17/04; F25D17/06; F25D17/062; F25D17/065; F25D21/00; F25D21/002; F25D21/04; F25D21/14; F25D23/00; F25D23/12; F25D23/123; G; G05; G05D; G05D23/00; G05D23/19; G05D23/20; G05D23/24; G05D23/2401; F25C2400/00; F25C2400/10; F25D2400/00; F25D2400/04
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
222 words
A refrigerator including a cabinet having below freezing and above freezing compartments to be kept cool, insulated partition means separating said compartments including a mullion exposed to the outside air, refrigerating means including an evaporator for cooling said compartments respectively to below and above freezing temperatures and incidentally accumulating frost upon said evaporator, means for periodically defrosting said evaporator, drainage means for disposing of the defrost water from said evaporator, an icemaker in said below freezing compartment provided with water delivery means for delivering water thereto, said cabinet being provided with a butter compartment for cooling butter preferably at a slightly higher temperature than the temperature in the above freezing compartment, wherein the invention comprises self-controlling positive temperature coefficient thermistor heaters associated with said bUtter compartment and said drainage means and said water delivery means and said icemaker and said mullion each of said thermistor heaters connected across the refrigerator power supply conductors so as to be continually energized, said thermistor heaters operative for supplying a small amount of heat in said locations at low temperatures to prevent freezing of the water in said drainage means and said water delivery means and to prevent the condensation of the water vapor upon said mullion and to maintain said butter compartment at temperatures the desired amount above the temperatures of said above freezing compartment.
Claim 2
Dependent Claim
222 words
A refrigerator including a cabinet having below freezing and above freezing compartments to be kept cool, insulated partition means separating said compartments including a mullion exposed to the outside air, refrigerating means including an evaporator for cooling said compartments respectively to below and above freezing temperatures and incidentally accumulating frost upon said evaporator, means for periodically defrosting said evaporator, drainage means for disposing of the defrost water from said evaporator, an icemaker in said below freezing compartment provided with water delivery means for delivering water thereto, said cabinet being provided with a butter compartment for cooling butter preferably at a slightly higher temperature than the temperature in the above freezing compartment, wherein the invention comprises self-controlling positive temperature coefficient thermistor heaters associated with said bUtter compartment and said drainage means and said water delivery means and said icemaker and said mullion each of said thermistor heaters connected across the refrigerator power supply conductors so as to be continually energized, said thermistor heaters operative for supplying a small amount of heat in said locations at low temperatures to prevent freezing of the water in said drainage means and said water delivery means and to prevent the condensation of the water vapor upon said mullion and to maintain said butter compartment at temperatures the desired amount above the temperatures of said above freezing compartment.
Claim 3
Dependent Claim
133 words
A refrigerator including a cabinet having a below freezing compartment, refrigerating means for cooling said compartment to below freezing temperatures, an icemaker in said below freezing compartment provided with water delivery means for delivering water thereto, wherein the improvement comprises a positive temperature coefficient thermistor heater connected across the refrigerator power supply conductors so as to be continually energized, said thermistor heater in heat transfer with said water delivery means for said icemaker, said thermistor heater connected in parallel circuit with the icemaker thereby causing a sharply reduced lower current when said thermistor heater rises to temperatures to and above a range of 40* to 50* F., said thermistor heater operative for supplying a small amount of heat thereto at low temperatures to prevent the freezing of water in said water delivery means.
Claim 4
Dependent Claim
133 words
A refrigerator including a cabinet having a below freezing compartment, refrigerating means for cooling said compartment to below freezing temperatures, an icemaker in said below freezing compartment provided with water delivery means for delivering water thereto, wherein the improvement comprises a positive temperature coefficient thermistor heater connected across the refrigerator power supply conductors so as to be continually energized, said thermistor heater in heat transfer with said water delivery means for said icemaker, said thermistor heater connected in parallel circuit with the icemaker thereby causing a sharply reduced lower current when said thermistor heater rises to temperatures to and above a range of 40* to 50* F., said thermistor heater operative for supplying a small amount of heat thereto at low temperatures to prevent the freezing of water in said water delivery means.
Claim 5
Dependent Claim
92 words
A refrigerator including a compartment to be kept cool, refrigerating means including an evaporator for cooling said compartment, means for periodically defrosting said evaporator, drainage means for disposing of the defrost water from said evaporator, wherein the improvement comprises a positive temperature coefficient thermistor heater connected across the refrigerator power supply conductors so as to be continually energized, said thermistor heater in heat transfer with said drainage means for supplying a small amount of heat in said location at low temperatures to prevent the freezing of the water in said drainage means.
Claim 6
Dependent Claim
92 words
A refrigerator including a compartment to be kept cool, refrigerating means including an evaporator for cooling said compartment, means for periodically defrosting said evaporator, drainage means for disposing of the defrost water from said evaporator, wherein the improvement comprises a positive temperature coefficient thermistor heater connected across the refrigerator power supply conductors so as to be continually energized, said thermistor heater in heat transfer with said drainage means for supplying a small amount of heat in said location at low temperatures to prevent the freezing of the water in said drainage means.
Claim 7
Dependent Claim
110 words
A refrigerator including a cabinet having a compartment to be kept cool, refrigerating means for cooling said compartment to suitable refrigerating temperatures, said cabinet also being provided with a butter compartment for storage of butter, wherein the improvement comprises a self-controlled positive temperature coefficient thermistor heater connected across the refrigerator power supply conductors so as to be continually energized, said thermistor heater in heat transfer with said butter compartment providing a sharp drop in current flow as the temperature rises to and above the range of about 45* to 55* F. to maintain said butter compartment at temperatures a desired amount above the temperature normally maintained in said refrigerating compartment.
Claim 8
Dependent Claim
110 words
A refrigerator including a cabinet having a compartment to be kept cool, refrigerating means for cooling said compartment to suitable refrigerating temperatures, said cabinet also being provided with a butter compartment for storage of butter, wherein the improvement comprises a self-controlled positive temperature coefficient thermistor heater connected across the refrigerator power supply conductors so as to be continually energized, said thermistor heater in heat transfer with said butter compartment providing a sharp drop in current flow as the temperature rises to and above the range of about 45* to 55* F. to maintain said butter compartment at temperatures a desired amount above the temperature normally maintained in said refrigerating compartment.
Claim 9
Dependent Claim
129 words
A refrigerator including a cabinet having a compartment to be kept cool, refrigerating means for cooling said compartment and incidentally cooling surfaces of the cabinet around the door of the compartment exposed to the outside air, wherein the improvement comprises a positive temperature coefficient thermistor heater in heat transfer with said portion of said surfaces of said cabinet around the door exposed to outside air said thermistor heater connected across the refrigerator supply conductors so as to be continually energized, said thermistor heater operative for supplying a small amount of heat thereto at low temperatures to prevent the condensation of moisture upon said exposed surfaces while reducing the current flow in said thermistor heater at outside air temperatures above approximately 90* F. to prevent overheating of said cabinet surfaces.
Claim 10
Dependent Claim
129 words
A refrigerator including a cabinet having a compartment to be kept cool, refrigerating means for cooling said compartment and incidentally cooling surfaces of the cabinet around the door of the compartment exposed to the outside air, wherein the improvement comprises a positive temperature coefficient thermistor heater in heat transfer with said portion of said surfaces of said cabinet around the door exposed to outside air said thermistor heater connected across the refrigerator supply conductors so as to be continually energized, said thermistor heater operative for supplying a small amount of heat thereto at low temperatures to prevent the condensation of moisture upon said exposed surfaces while reducing the current flow in said thermistor heater at outside air temperatures above approximately 90* F. to prevent overheating of said cabinet surfaces.
Claim 11
Dependent Claim
140 words
A refrigerator including a cabinet having a compartment to be kept cool, refrigerating means for cooling said compartment, a thermostatic switch having an operatIng fluid motor in the form of a bellows and a thermosensitive bulb in the form of a long closed tube connected thereto containing a volatile liquid for controlling said refrigerating means, wherein the improvement comprises positive temperature coefficient thermistor heater connected across the refrigerator supply conductors so as to be continually energized, said thermistor heater in heat transfer with said fluid motor bellows to maintain said bellows at temperatures slightly higher than said thermosensitive tubing, said thermistor heater reducing its heating effect when its temperature rises to the range of 50* to 60* F. for ensuring that the thermostatic switch and the refrigerator means are continuously controlled in accordance with the temperature of the thermosensitive tubing.
Claim 12
Dependent Claim
140 words
A refrigerator including a cabinet having a compartment to be kept cool, refrigerating means for cooling said compartment, a thermostatic switch having an operatIng fluid motor in the form of a bellows and a thermosensitive bulb in the form of a long closed tube connected thereto containing a volatile liquid for controlling said refrigerating means, wherein the improvement comprises positive temperature coefficient thermistor heater connected across the refrigerator supply conductors so as to be continually energized, said thermistor heater in heat transfer with said fluid motor bellows to maintain said bellows at temperatures slightly higher than said thermosensitive tubing, said thermistor heater reducing its heating effect when its temperature rises to the range of 50* to 60* F. for ensuring that the thermostatic switch and the refrigerator means are continuously controlled in accordance with the temperature of the thermosensitive tubing.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-01-10 | 1975-07-12 | 1976-01-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-01-10 | 1979-07-12 | 1980-01-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-01-10 | 1983-07-12 | 1984-01-11 | $7700.00 | Window Closed / Lapsed |