US4334541A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Thermal protective circuit for a hyperemia-inducing physiological sensor
Assignee: GE Medical Systems Information Technologies GmbH
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Filing: 1980-03-17
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Granted: 1982-06-15
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Expires: 2000-03-17
Abstract
Abstract A sensor for transcutaneous measurement of physiological phenomena of living tissues is provided with a thermostatically-controlled electric heater. The purpose of the heater is to induce local hyperemia to enable operation of the sensor. The heater is thermostatically controlled. An independent temperature sensor is provided to disable the heater in the event of catastrophic failure of the thermostat circuit.
Inventors
- 👤 Helmut Leist
- 👤 Georg J. Ullrich
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 22:00
CPC Classifications
A; A61; A61B; A61B5/00; A61B5/145; A61B5/1491; G; G05; G05D; G05D23/00; G05D23/19; G05D23/1927; G05D23/1928; G12; G12B; G12B7/00
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
105 words
A physiological sensor for the transcutaneous determination of physiological phenomena, comprising a heater element; a remote source of power for energizing the heater element; control means, including the power source, the heater element and a first temperature-responsive device, for thermostatically maintaining the temperature of the sensor substantially constant during normal use of the sensor; and safety means, including a second temperature-responsive device, for interrupting energization of the heater element by maintaining the heater element disconnected from the power source whenever, due to failure of the control means, the temperature of the sensor exceeds a predetermined ceiling level, until intervention by an operator restores energization conditions.
Claim 2
Dependent Claim
105 words
A physiological sensor for the transcutaneous determination of physiological phenomena, comprising a heater element; a remote source of power for energizing the heater element; control means, including the power source, the heater element and a first temperature-responsive device, for thermostatically maintaining the temperature of the sensor substantially constant during normal use of the sensor; and safety means, including a second temperature-responsive device, for interrupting energization of the heater element by maintaining the heater element disconnected from the power source whenever, due to failure of the control means, the temperature of the sensor exceeds a predetermined ceiling level, until intervention by an operator restores energization conditions.
Claim 3
Dependent Claim
25 words
Sensor in accordance with claim 2, wherein the safety means include a normally-closed temperature-sensitive switch cooperating with a latching relay which is resettable by hand.
Claim 4
Dependent Claim
20 words
Sensor in accordance with claim 2, wherein the safety means include an alloy link of the nature of a fuse.
Claim 5
Dependent Claim
17 words
Sensor in accordance with claim 3, wherein the melting point of the alloy link is 46.5° Centigrade.
References Cited (Backward Citations)
US1749718A
Cited
US3516411A
Cited
US4005700A
Cited
US4190053A
Cited
US4186294A
Cited
US4252123A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-06-14 | 1985-12-14 | 1986-06-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-06-14 | 1989-12-14 | 1990-06-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-06-14 | 1993-12-14 | 1994-06-15 | $7700.00 | Window Closed / Lapsed |