US3753259A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Cooler and freezer failure warning system
Assignee: Individual
•
Filing: 1971-08-30
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Granted: 1973-08-14
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Expires: 1991-08-30
Abstract
Abstract Cooling failure warning system for a refrigerated food case or the like, including a source of a rectified, pulsating, supply signal, a source of a lower regulated signal supplied by the supply signal source, a temperature sensor installed in a selected location of the food case and responsively variable in resistance according to its sensed temperature, means responsive to the sensor resistance for producing a switch signal at a predetermined overtemperature condition, means responsive to the switch signal for producing a delayed switch signal, a temperature alarm device, and an alarm switch responsive to the delayed switch signal for applying the supply signal to energize the temperature alarm device. The warning system further includes fail-safe provisions for producing an alarm in the event of sensor failure. A power failure alarm device responsive to a loss of the regulated signal can also be included in the warning system.
Inventors
- 👤 R Donovan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 06:25
CPC Classifications
G; G01; G01K; G01K3/00; G01K3/005; F; F25; F25D; F25D29/00; F25D29/008; G01K1/00; G01K1/02; G01K1/024
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
130 words
A cooling failure warning system for a refrigerated food case and the like, said system comprising: a source of a rectified, pulsating, supply signal; temperature sensor means installed in a selected location of said food case, said sensor means being responsively variable in output in accordance with its sensed temperature; means responsive to said sensor means output and producing a switch signal for a sensor means output corresponding to a sensed temperature of at least a predetermined value higher than operationally normal for said food case; temperature alarm means; alarm switch means responsive to said switch signal for applying said supply signal to energize said temperature alarm means; and means for delaying said switch signal a predetermined period of time and accordingly the response of said alarm switch means thereto.
Claim 2
Dependent Claim
130 words
A cooling failure warning system for a refrigerated food case and the like, said system comprising: a source of a rectified, pulsating, supply signal; temperature sensor means installed in a selected location of said food case, said sensor means being responsively variable in output in accordance with its sensed temperature; means responsive to said sensor means output and producing a switch signal for a sensor means output corresponding to a sensed temperature of at least a predetermined value higher than operationally normal for said food case; temperature alarm means; alarm switch means responsive to said switch signal for applying said supply signal to energize said temperature alarm means; and means for delaying said switch signal a predetermined period of time and accordingly the response of said alarm switch means thereto.
Claim 3
Dependent Claim
45 words
The invention as defined in claim 1 further comprising means responsive to said sensor means output and producing said switch signal at a sensor means output corresponding to a sensed temperature of at least a predetermined value lower than operationally normal for said food case.
Claim 4
Dependent Claim
42 words
The invention as defined in claim 1, further comprising power alarm means, and means responsive to a loss of said supply signal of at least a predetermined amount and producing a power alarm signal for causing energization of said power alarm means.
Claim 5
Dependent Claim
130 words
The invention as defined in claim 1 further comprising a source of a regulated signal, and wherein said sensor means is responsively variable in output resistance in accordance with its sensed temperature, and said means responsive to said sensor means output for producing a switch signal includes a reference divider network energized by said regulated signal and having a first output signal obtained from a first selected point thereof, said sensor means being connected to said network to vary said first output signal according to the variation of said sensor means resistance, and amplifier means responsive to said first output signal for producing said switch signal at a sensor means resistance corresponding to a sensed temperature of at least a predetermined value higher than operationally normal for said food case.
Claim 6
Dependent Claim
51 words
The invention as defined in claim 4 further comprising timing switch means responsive to said switch signal for initiating production of a timed output signal from said delay means, said alarm switch means being responsive to said timed output signal to apply said supply signal to energize said temperature alarm means.
Claim 7
Dependent Claim
55 words
The invention as defined in claim 5 wherein said regulated signal source is supplied by said supply signal source, and further comprising power alarm means, and means responsive to a loss of said regulated signal of at least a predetermined amount and producing a power alarm signal for causing energization of said power alarm means.
Claim 8
Dependent Claim
72 words
The invention as defined in claim 5 further comprising means connected to a second selected point of said network to obtain a second output signal therefrom when said sensor means resistance is at least of a predetermined value corresponding to a sensed temperature of at least a predetermined value lower than operationally normal for said food case, said amplifier means being responsive to said second output signal to produce said switch signal.
Claim 9
Dependent Claim
72 words
The invention as defined in claim 4 further comprising means connected to a second selected point of said network to obtain a second output signal therefrom when said sensor means resistance is at least of a predetermined value corresponding to a sensed temperature of at least a predetermined value lower than operationally normal for said food case, said amplifier means being respoNsive to said second output signal to produce said switch signal.
Claim 10
Dependent Claim
51 words
The invention as defined in claim 8 further comprising timing switch means responsive to said switch signal for initiating production of a timed output signal from said delay means, said alarm switch means being responsive to said timed output signal to apply said supply signal to energize said temperature alarm means.
Claim 11
Dependent Claim
55 words
The invention as defined in claim 9 wherein said regulated signal source is supplied by said supply signal source, and further comprising power alarm means, and means responsive to a loss of said regulated signal of at least a predetermined amount and producing a power alarm signal for causing energization of said power alarm means.
Claim 12
Dependent Claim
169 words
A cooling failure warning system for a refrigerated food case and the like, said system comprising: a source of electric power, and electric signaling means connected to said source; temperature sensor means connected to said signaling means and adapted to be installed in a selected location in a food case to sense the ambient temperature, said sensor means being responsively variable in output in accordance with its sensed temperature; said signaling means including means connected to said sensor means and responsive thereto to produce a switch signal for a sensor means output corresponding to a sensed temperature of at least a predetermined value higher than operationally normal for said food case; adjustable timing means connected to said switch signal producing means for delaying transmission of said switch signal for a predetermined period of time; temperature alarm means; and alarm switch means connected to said timing means to receive said switch signal upon completion of the timing delay and responsive to said switch signal to energize said temperature alarm means.
Claim 13
Dependent Claim
169 words
A cooling failure warning system for a refrigerated food case and the like, said system comprising: a source of electric power, and electric signaling means connected to said source; temperature sensor means connected to said signaling means and adapted to be installed in a selected location in a food case to sense the ambient temperature, said sensor means being responsively variable in output in accordance with its sensed temperature; said signaling means including means connected to said sensor means and responsive thereto to produce a switch signal for a sensor means output corresponding to a sensed temperature of at least a predetermined value higher than operationally normal for said food case; adjustable timing means connected to said switch signal producing means for delaying transmission of said switch signal for a predetermined period of time; temperature alarm means; and alarm switch means connected to said timing means to receive said switch signal upon completion of the timing delay and responsive to said switch signal to energize said temperature alarm means.
Claim 14
Dependent Claim
53 words
The invention as defined in claim 11 wherein said sensor means comprises a plurality of discrete sensors adapted to be arranged in spaced relation and connected in series to the switch signal producing means; the latter being responsive to an overtemperature indication from any one of said sensors to produce a switch signal.
Claim 15
Dependent Claim
28 words
The invention as defined in claim 11 where the switch signal producing means is responsive to an open circuit in the sensor means to produce a switch signal.
Claim 16
Dependent Claim
44 words
The invention as defined in claim 11 further comprising power alarm means; and means responsive to a loss of power of at least a predetermined amount in said signaling means and producing a power alarm signal for causing energization of said power alarm means.
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) | 1976-08-13 | 1977-02-12 | 1977-08-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-08-13 | 1981-02-12 | 1981-08-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-08-13 | 1985-02-12 | 1985-08-14 | $7700.00 | Window Closed / Lapsed |