US4031352A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electric blanket
Assignee: C S OOSTERBERG Ltd Pty
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Filing: 1975-10-16
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Granted: 1977-06-21
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Expires: 1995-10-16
Abstract
Abstract An electric blanket assembly having a blanket whose heating elements are supplied from a low voltage supply source and a control circuit assembly adapted both to regulate the heating of the blanket and to disconnect the supply source from the heating elements under conditions of malfunction of the assembly. The control circuit includes temperature sensitive elements suitably located in the blanket and associated circuitry arranged to generate a control voltage which is selectable and reference voltage generating means which is also selectable. The control circuit also includes means to compare the control voltage and the reference voltage and to control current flow through the heating elements.
Inventors
- 👤 Cedric Siegfried Oosterberg
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 14:20
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; H05B1/00; H05B1/02; H05B1/0227; H05B2203/00; H05B2203/035
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
119 words
An electric blanket assembly including a blanket having elements adapted to be heated from an electric supply source and a control circuit assembly adapted to control current through the elements to regulate the heating of the blanket and further adapted to disconnect the supply source from the heating elements under conditions of malfunction of the blanket, characterised in that the control circuit assembly includes temperature sensitive elements suitably located in the blanket and arranged to generate a control voltage, timing means adapted to generate a reference voltage and regulating means to compare the control voltage and the reference voltage and to trigger a solid state switching device which is adapted to control the current through the blanket heating elements.
Claim 2
Dependent Claim
119 words
An electric blanket assembly including a blanket having elements adapted to be heated from an electric supply source and a control circuit assembly adapted to control current through the elements to regulate the heating of the blanket and further adapted to disconnect the supply source from the heating elements under conditions of malfunction of the blanket, characterised in that the control circuit assembly includes temperature sensitive elements suitably located in the blanket and arranged to generate a control voltage, timing means adapted to generate a reference voltage and regulating means to compare the control voltage and the reference voltage and to trigger a solid state switching device which is adapted to control the current through the blanket heating elements.
Claim 3
Dependent Claim
26 words
The electric blanket assembly claimed in claim 1 wherein the regulating means includes differential amplifier circuitry, zero crossing detector amplifier circuitry and an output pluse circuit.
Claim 4
Dependent Claim
35 words
The electric blanket assembly claimed in claim 2 wherein the control voltage is applied to one input of the differential amplifier and the reference voltage is applied to the other input of the differential amplifier.
Claim 5
Dependent Claim
29 words
The electric blanket assembly claimed in claim 3 in which the output pulse circuit is connected to the solid state switching device and is adapted to trigger the latter.
Claim 6
Dependent Claim
18 words
The electric blanket assembly claim in claim 4 in which the solid state switching device is a triac.
Claim 7
Dependent Claim
30 words
The electric blanket assembly as claimed in claim 1 wherein the reference voltage is of a ramp like nature and is arranged to be cyclic with a preset time period.
Claim 8
Dependent Claim
19 words
The electric blanket assembly as claimed in claim 1 wherein the temperature sensitive elements are negative temperature coefficient thermistors.
Claim 9
Dependent Claim
76 words
The electric blanket assembly claimed in claim 1 wherein the control circuit assembly includes means to disconnect the supply source from the heating elements under conditions of malfunction of the blanket which is connected to the control voltage generated by the temperature sensitive elements and which is adapted to operate a relay to disconnect the supply from the heating elements, and further including differential amplifier circuitry, zero crossing detector amplifier circuitry and an output pulse circuit.
Claim 10
Dependent Claim
26 words
The electric blanket assembly claimed in claim 8 in which the output pulses from the output pulse circuit act to trigger a solid state switching device.
Claim 11
Dependent Claim
18 words
The electric blanket assembly claimed in claim 9 in which the solid state switching device is a triac.
Claim 12
Dependent Claim
18 words
The electric blanket assembly claimed in claim 1 in which the control circuit assembly includes a visible alarm.
Claim 13
Dependent Claim
16 words
The electric blanket assembly claimed in claim 11 in which the alarm is a visible alarm.
Claim 14
Dependent Claim
16 words
The electric blanket assembly claimed in claim 11 in which the alarm is visible and audible.
Claim 15
Dependent Claim
24 words
The electric blanket assembly claimed in claim 13 wherein the control circuit assembly includes delay circuitry to delay the triggering of the audible alarm.
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) | 1980-06-20 | 1980-12-20 | 1981-06-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-06-20 | 1984-12-20 | 1985-06-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-06-20 | 1988-12-20 | 1989-06-21 | $7700.00 | Window Closed / Lapsed |