Patent US3673381A successfully refreshed from Google Patents.
US3673381A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Thermostatless blanket control circuit
Assignee: Nortel Networks Ltd
•
Filing: 1971-10-26
•
Granted: 1972-06-27
•
Expires: 1991-10-26
Abstract
Abstract An overload protection circuit for an electric heating blanket is provided. A sensing element in the blanket is coupled to a neon-filled diode. When an overload condition is sensed the diode ceases to emit light and a bimetallic element in series with a light-responsive resistor causes a pair of contacts in series with the heating element to open.
Inventors
- 👤 George C Crowley
- 👤 Gordon S Carlson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 15:06
CPC Classifications
H; H05; H05B; H05B3/00; H05B3/20; H05B3/34; H05B3/342; G; G05; G05D; G05D23/00; G05D23/19; G05D23/1906; G05D23/1909; G05D23/20; G05D23/24; H02; H02H; H02H5/00; H02H5/04; H02H5/042; H02H5/043; H05B2203/00; H05B2203/014
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
152 words
An overload protection circuit for an electric blanket having a heating means and a sensing means which has a resistance that decreases with increasing temperature, the sensing means being located in proximity in said blanket to said heating means and electrically coupled in parallel with said heating means, comprising a diode filled with an ionizable gas which emitts radiation wen said gas is ionized; said diode being coupled in series with said sensing means, control means having a pair of overload contacts which are coupled in series with said heating means and radiation responsive means coupled to said control means and positioned to receive said radiation from said diode; said control means being constructed to control the opening and closing of said overload contacts in accordance with the condition of said radiation responsive means wherein said condition changes in accordance with the radiation received by said radiation responsive means from said diode.
Claim 2
Dependent Claim
152 words
An overload protection circuit for an electric blanket having a heating means and a sensing means which has a resistance that decreases with increasing temperature, the sensing means being located in proximity in said blanket to said heating means and electrically coupled in parallel with said heating means, comprising a diode filled with an ionizable gas which emitts radiation wen said gas is ionized; said diode being coupled in series with said sensing means, control means having a pair of overload contacts which are coupled in series with said heating means and radiation responsive means coupled to said control means and positioned to receive said radiation from said diode; said control means being constructed to control the opening and closing of said overload contacts in accordance with the condition of said radiation responsive means wherein said condition changes in accordance with the radiation received by said radiation responsive means from said diode.
Claim 3
Dependent Claim
36 words
An overload protection circuit as set forth in claim 1 wherein said radiation responsive means is a resistor which has a resistance that varies as a function of the radiation said resistor receives from said diode.
Claim 4
Dependent Claim
41 words
An overload protection circuit as set forth in claim 2 further comprising a blanket energizing switch means which has contacts that momentarily place line voltage across said resistor when said switch is being changed from its off and its on position.
Claim 5
Dependent Claim
40 words
An overload protection circuit as set forth in claim 1 wherein said control means is a bimetallic control element that is coupled in series with said radiation responsive means across said series combination of said diode and said sensing means.
Claim 6
Dependent Claim
36 words
An overload protection circuit as set forth in claim 4 wherein said radiation responsive means is a resistor which has a resistance that varies as a function of the radiation said resistor receives from said diode.
Claim 7
Dependent Claim
41 words
An overload protection circuit as set forth in claim 5 further comprising a blanket energizing switch means which has contacts that momentarily place line voltage across said resistor when said switch is being changed from its off to its on position.
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) | 1975-06-27 | 1975-12-27 | 1976-06-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-06-27 | 1979-12-27 | 1980-06-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-06-27 | 1983-12-27 | 1984-06-27 | $7700.00 | Window Closed / Lapsed |