US4484050A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electric cooking oven having a temperature sensing device with output compensation
Assignee: Sanyo Electric Co Ltd
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Filing: 1983-07-18
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Granted: 1984-11-20
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Expires: 2003-07-18
Abstract
Abstract An electric cooking oven for use a normal cooking mode and defrost mode is provided which comprises a detector for detecting a temperature of a food body during cooking thereof, the detector comprising a thermistor which detachably attached to the food body to sense the temperature thereof. A circuit is provided for compensating the gradient of the output characteristics of the temperature detector to increase the gradient of the output characteristic curve of the resistance of the thermistor as a function of temperature in when the thermistor is operating in a temperature range in which it has a low accuracy of temperature sensing.
Inventors
- 👤 Atsushi Horinouchi
- 👤 Satoshi Koide
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 14:26
CPC Classifications
H; H05; H05B; H05B6/00; H05B6/64; H05B6/6447; H05B6/645; H05B6/6452; G; G01; G01K; G01K7/00; G01K7/16; G01K7/22; G01K7/24; G01K7/25; G01K2207/00; G01K2207/02; G01K2207/06
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
207 words
An electric cooking oven comprising means for accommodating a food body to be cooked, means for heating said food body, means for detecting the temperature of said food body during the cooking thereof, said detecting means comprising a thermistor which is detachably attached to the food body to sense the temperature thereof wherein the thermistor has an output characteristic curve of resistance as a function of temperature with a first temperature range in which the error range of the resistance of the thermistor relative to the temperature is smaller than a predetermined value and a second temperature range in which the error range of the resistance of the thermistor relative to the temperature is larger than the predetermined value, an electric circuit means for converting the temperature sensed by the thermistor to an electric signal, a control means for controlling the electric power supplied to the heating means in response to the temperature signal from said circuit means to cook the food body under temperature control, instruction means for operating the thermistor in said second temperature range, and changing means for changing the characteristic curve to thereby increase the gradient of the characteristic curve of the resistance when the thermistor is operating in the second temperature range.
Claim 2
Dependent Claim
207 words
An electric cooking oven comprising means for accommodating a food body to be cooked, means for heating said food body, means for detecting the temperature of said food body during the cooking thereof, said detecting means comprising a thermistor which is detachably attached to the food body to sense the temperature thereof wherein the thermistor has an output characteristic curve of resistance as a function of temperature with a first temperature range in which the error range of the resistance of the thermistor relative to the temperature is smaller than a predetermined value and a second temperature range in which the error range of the resistance of the thermistor relative to the temperature is larger than the predetermined value, an electric circuit means for converting the temperature sensed by the thermistor to an electric signal, a control means for controlling the electric power supplied to the heating means in response to the temperature signal from said circuit means to cook the food body under temperature control, instruction means for operating the thermistor in said second temperature range, and changing means for changing the characteristic curve to thereby increase the gradient of the characteristic curve of the resistance when the thermistor is operating in the second temperature range.
Claim 3
Dependent Claim
27 words
An electric cooking oven according to claim 1, wherein the temperature range in which the gradient of the characteristic curve is increased is a defrost temperature range.
Claim 4
Dependent Claim
27 words
An electric cooking oven according to claim 1, wherein the temperature range in which the gradient of the characteristic curve is increased is a high temperature range.
Claim 5
Dependent Claim
44 words
An electric cooking oven according to any one of claims 1, 2 or 3 wherein said changing means comprises resistor means connected in series with the thermistor wherein the resistance of the resistor means is changed depending on the cooking mode of the oven.
Claim 6
Dependent Claim
25 words
An electric cooking oven according to claim 4, wherein said resistor means comprises two fixed resistors connected in parallel relation through a first switching means.
Claim 7
Dependent Claim
24 words
An electric cooking oven according to claim 5, wherein said first switching means is a transistor controlled by the output of the control means.
Claim 8
Dependent Claim
28 words
An electric cooking oven according to claim 6, wherein said changing, means further comprises an additional resistor connected in parallel with the thermistor through a second switching means.
Claim 9
Dependent Claim
28 words
An electric cooking oven according to claim 7, wherein said second switching means is controlled by the output of the control means synchronized with the first switching means.
Claim 10
Dependent Claim
54 words
An electric cooking oven according to claim 8, wherein said control means comprises a comparator circuit having one input terminal connected with the thermistor, another input terminal connected to receive a temperature reference signal and an output terminal thereof connected with means for producing a signal to control said first and second swiching means.
Claim 11
Dependent Claim
37 words
An electric cooking oven according to claim 9, wherein said means for producing a signal to control said first switching means and the second switching means is responsive to the instructions from a keyboard of the oven.
Claim 12
Dependent Claim
35 words
An electric cooking oven according to claim 1, wherein said control means is operable in either a defrost mode or a normal cooking mode in response to the instructions fed thereto from said instruction means.
Claim 13
Dependent Claim
15 words
An electric cooking oven according to claim 1, wherein said heating means is a magnetron.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-11-20 | 1988-05-21 | 1988-11-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-11-20 | 1992-05-21 | 1992-11-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-11-20 | 1996-05-21 | 1996-11-20 | $7700.00 | Window Closed / Lapsed |