US4285207A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Air conditioning apparatus comprising refrigerant shortage sensor
Assignee: Bosch Corp
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Filing: 1979-07-23
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Granted: 1981-08-25
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Expires: 1999-07-23
Abstract
Abstract A float operated switch (21) is actuated when the level of refrigerant fluid in a reservoir (11) is below a predetermined value to produce an electrical signal. The signal is delayed by 10 to 30 seconds and applied to a switch circuit (54) to disengage an electromagnetic clutch (63) and thereby de-energize a compressor (64). The clutch (63) is also disengaged by the action of a thermal switch (61) when the temperature in a space which is being air conditioned drops below a predetermined value. The operation of the float operated switch (21) is inhibited when the sensed temperature is below the predetermined value and also when a motor which drives the compressor (64) is not operating to prevent erroneous de-energization of the compressor (64).
Inventors
- 👤 Hiroyuki Sugiura
- 👤 Ryota Hasegawa
- 👤 Teruo Nakamura
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 21:50
CPC Classifications
G; G05; G05D; G05D23/00; G05D23/19; G05D23/275; B; B60; B60H; B60H1/00; B60H1/32; B60H1/3204; B60H1/3225; F; F25; F25B; F25B49/00; F25B49/005; G01; G01F; G01F23/00; G01F23/30; G01F23/64; G01F23/72; G01F23/74; F25B2500/00; F25B2500/22; F25B2500/222; F25B2700/00; F25B2700/04
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
141 words
An air conditioning apparatus including a motor driven compressor and a refrigerant reservoir connected to the compressor, characterized by comprising: level sensor means for producing an electrical signal when a refrigerant level in the reservoir is below a predetermined value; level switch means for normally controlling the compressor to be motor driven and for controlling the compressor to be not motor driven in response to the electrical signal; p1 delay means connected between the level sensor means and the level switch means for delaying the electrical signal for a predetermined length of time; and temperature sensor means for controlling the compressor to be motor driven only when a sensed temperature is above a predetermined value; the temperature sensor means comprising means for inhibiting the level sensor means from producing the electrical signal when the sensed temperature is below the predetermined value.
Claim 2
Dependent Claim
141 words
An air conditioning apparatus including a motor driven compressor and a refrigerant reservoir connected to the compressor, characterized by comprising: level sensor means for producing an electrical signal when a refrigerant level in the reservoir is below a predetermined value; level switch means for normally controlling the compressor to be motor driven and for controlling the compressor to be not motor driven in response to the electrical signal; p1 delay means connected between the level sensor means and the level switch means for delaying the electrical signal for a predetermined length of time; and temperature sensor means for controlling the compressor to be motor driven only when a sensed temperature is above a predetermined value; the temperature sensor means comprising means for inhibiting the level sensor means from producing the electrical signal when the sensed temperature is below the predetermined value.
Claim 3
Dependent Claim
22 words
An apparatus as in claim 1, in which the level sensor means comprises a float and a switch actuated by the float.
Claim 4
Dependent Claim
25 words
An apparatus as in claim 1, further comprising operation sensor means for sensing motor operation and enabling the level sensor means only in response thereto.
Claim 5
Dependent Claim
26 words
An apparatus as in claim 1, in which the temperature sensor means comprises a thermal switch which is connected in series with the level switch means.
Claim 6
Dependent Claim
27 words
An apparatus as in claim 4, further comprising a power source which is connected across the series combination of the level switch means and the thermal switch.
Claim 7
Dependent Claim
35 words
An apparatus as in claim 5, in which the level sensor means is adapted to be powered by the power source, the thermal switch being connected between the power source and the level sensor means.
Claim 8
Dependent Claim
21 words
An apparatus as in claim 1, in which the temperature sensor means is connected in parallel with the level sensor means.
Claim 9
Dependent Claim
15 words
An apparatus as in claim 1, in which the temperature sensor means comprises a thermistor.
Claim 10
Dependent Claim
15 words
An apparatus as in claim 1, in which the temperature sensor means comprises hysteresis means.
Claim 11
Dependent Claim
140 words
An air conditioning apparatus including a motor driven compressor and a refrigerant reservoir connected to the compressor, characterized by comprising: level sensor means for producing an electrical signal when a refrigerant level in the reservoir is below a predetermined value; level switch means for normally controlling the compressor to be motor driven and for controlling the compressor to be to be not motor driven in response to the electrical signal; delay means connected between the level sensor means and the level switch means for delaying the electrical signal for a predetermined length of time; and operation sensor means for sensing motor operation and enabling the sensor means only in response thereto; the delay means comprising a time constant circuit including a resistor and a capacitor, the operation sensor means comprising means for discharging the capacitor in response to motor non-operation.
Claim 12
Dependent Claim
140 words
An air conditioning apparatus including a motor driven compressor and a refrigerant reservoir connected to the compressor, characterized by comprising: level sensor means for producing an electrical signal when a refrigerant level in the reservoir is below a predetermined value; level switch means for normally controlling the compressor to be motor driven and for controlling the compressor to be to be not motor driven in response to the electrical signal; delay means connected between the level sensor means and the level switch means for delaying the electrical signal for a predetermined length of time; and operation sensor means for sensing motor operation and enabling the sensor means only in response thereto; the delay means comprising a time constant circuit including a resistor and a capacitor, the operation sensor means comprising means for discharging the capacitor in response to motor non-operation.
Claim 13
Dependent Claim
146 words
An air conditioning apparatus including a motor driven compressor and a refrigerant reservoir connected to the compressor, characterized by comprising: level sensor means for producing an electrical signal when a refrigerant level in the reservoir is below a predetermined value; level switch means for normally controlling the compressor to be motor driven and for controlling the compressor to be not motor driven in response to the electrical signal; delay means connected between the level sensor means and the level switch means for delaying the electrical signal for a predetermined length of time; temperature sensor means for controlling the compressor to be motor driven only when a sensed temperature is above a predetermined value; the delay means comprising a time constant circuit including a resistor and a capacitor, the temperature sensor means comprising means for discharging the capacitor when the sensed temperature is below the predetermined value.
Claim 14
Dependent Claim
146 words
An air conditioning apparatus including a motor driven compressor and a refrigerant reservoir connected to the compressor, characterized by comprising: level sensor means for producing an electrical signal when a refrigerant level in the reservoir is below a predetermined value; level switch means for normally controlling the compressor to be motor driven and for controlling the compressor to be not motor driven in response to the electrical signal; delay means connected between the level sensor means and the level switch means for delaying the electrical signal for a predetermined length of time; temperature sensor means for controlling the compressor to be motor driven only when a sensed temperature is above a predetermined value; the delay means comprising a time constant circuit including a resistor and a capacitor, the temperature sensor means comprising means for discharging the capacitor when the sensed temperature is below the predetermined value.
Claim 15
Dependent Claim
132 words
An air conditioning apparatus including a motor driven compressor and a refrigerant reservoir connected to the compressor, characterized by comprising: level sensor means for producing an electrical signal when a refrigerant level in the reservoir is below a predetermined value; level switch means for normally controlling the compressor to be motor driven and for controlling the compressor to be not motor driven in response to the electrical signal; delay means connected between the level sensor means and the level switch means for delaying the electrical signal for a predetermined length of time; and temperature sensor means for controlling the compressor to be motor driven only when a sensed temperature is above a predetermined value; the temperature sensor means comprising a thermal switch which is connected in series with the level switch means.
Claim 16
Dependent Claim
132 words
An air conditioning apparatus including a motor driven compressor and a refrigerant reservoir connected to the compressor, characterized by comprising: level sensor means for producing an electrical signal when a refrigerant level in the reservoir is below a predetermined value; level switch means for normally controlling the compressor to be motor driven and for controlling the compressor to be not motor driven in response to the electrical signal; delay means connected between the level sensor means and the level switch means for delaying the electrical signal for a predetermined length of time; and temperature sensor means for controlling the compressor to be motor driven only when a sensed temperature is above a predetermined value; the temperature sensor means comprising a thermal switch which is connected in series with the level switch means.
Claim 17
Dependent Claim
27 words
An apparatus as in claim 12, further comprising a power source which is connected across the series combination of the level switch means and the thermal switch.
Claim 18
Dependent Claim
35 words
An apparatus as in claim 13, in which the level sensor means is adapted to be powered by the power source, the thermal switch being connected between the power source and the level sensor 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) | 1984-08-24 | 1985-02-23 | 1985-08-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-08-24 | 1989-02-23 | 1989-08-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-08-24 | 1993-02-23 | 1993-08-25 | $7700.00 | Window Closed / Lapsed |