US4083197A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Air conditioner control system
Assignee: BorgWarner Automotive Electronic and Mechanical Systems Corp
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Filing: 1976-10-14
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Granted: 1978-04-11
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Expires: 1996-10-14
Abstract
Abstract A control system for air conditioning apparatus particularly of the type utilizing a variable displacement compressor, the capacity of which is modulated in response to a cooling demand control signal. More specifically, the capacity of the compressor is controlled in response to a first signal developed in response to the temperature of air within the space to be controlled and a second signal which is indicative of potential freezing of the evaporator coil. Both of these signals are applied to a control valve actuator which directly varies the capacity of the compressor in a modulated fashion above a predetermined combination of coil and air temperatures and reduces the capacity to zero when below said predetermined combination.
Inventors
- 👤 Andrew Peter Boehmer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 08:33
CPC Classifications
F; F25; F25B; F25B49/00; F25B49/02; F25B49/022
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
158 words
A control system for a space air conditioning apparatus of the type including a variable capacity compressor, a condenser, an expansion device and an evaporator all connected in closed circuit, series flow relation, and means for circulating air over said evaporator into the space to be conditioned, said system comprising: means for modulating the capacity of said compressor in response to: (1) the temperature of the air in the space to be conditioned and (2) the temperature of said evaporator, said last-named means including a control valve having a valve body and a moveable spool for controlling flow between inlet and outlet ports, a first spool actuator operated in response to the air space temperature and a second spool actuator operated in response to evaporator temperature, and means for coordinating the effect of said first and second spool actuators such that movement of the spool, and concomitant flow control, become an additive function of air and evaporator temperatures.
Claim 2
Dependent Claim
158 words
A control system for a space air conditioning apparatus of the type including a variable capacity compressor, a condenser, an expansion device and an evaporator all connected in closed circuit, series flow relation, and means for circulating air over said evaporator into the space to be conditioned, said system comprising: means for modulating the capacity of said compressor in response to: (1) the temperature of the air in the space to be conditioned and (2) the temperature of said evaporator, said last-named means including a control valve having a valve body and a moveable spool for controlling flow between inlet and outlet ports, a first spool actuator operated in response to the air space temperature and a second spool actuator operated in response to evaporator temperature, and means for coordinating the effect of said first and second spool actuators such that movement of the spool, and concomitant flow control, become an additive function of air and evaporator temperatures.
Claim 3
Dependent Claim
251 words
A control system for a space air conditioning apparatus of the type including a variable capacity compressor, a condenser, an expansion device and an evaporator all connected in closed circuit, series flow relation, and means for circulating air over said evaporator into the space to be conditioned, said system comprising: control means for modulating the capacity of said compressor in response to a control signal, said control signal being an additive function of: (1) the temperature of air in said space to be conditioned and (2) the temperature of said evaporator, said control means including a control valve for developing a pneumatic control signal for the modulation of said compressor; a first temperature sensor adapted to sense the temperature of air within the space to be conditioned and a second temperature sensor adapted to sense the temperature of said evaporator; means for combining the effects of variations in the respective temperatures sensed and applying the resultant to said control valve; said control valve including a valve body having fluid inlet and outlet ports, a moveable valve spool having means to control flow from said inlet port to said outlet port; a pair of pistons both being connected to said valve spool and means for applying a first pressure to one of said pistons and a second pressure to the other of said pistons, said first pressure being proportional to the temperature of air in the space to be conditioned and said second pressure being proportional to the temperature of said evaporator.
Claim 4
Dependent Claim
251 words
A control system for a space air conditioning apparatus of the type including a variable capacity compressor, a condenser, an expansion device and an evaporator all connected in closed circuit, series flow relation, and means for circulating air over said evaporator into the space to be conditioned, said system comprising: control means for modulating the capacity of said compressor in response to a control signal, said control signal being an additive function of: (1) the temperature of air in said space to be conditioned and (2) the temperature of said evaporator, said control means including a control valve for developing a pneumatic control signal for the modulation of said compressor; a first temperature sensor adapted to sense the temperature of air within the space to be conditioned and a second temperature sensor adapted to sense the temperature of said evaporator; means for combining the effects of variations in the respective temperatures sensed and applying the resultant to said control valve; said control valve including a valve body having fluid inlet and outlet ports, a moveable valve spool having means to control flow from said inlet port to said outlet port; a pair of pistons both being connected to said valve spool and means for applying a first pressure to one of said pistons and a second pressure to the other of said pistons, said first pressure being proportional to the temperature of air in the space to be conditioned and said second pressure being proportional to the temperature of said evaporator.
Claim 5
Dependent Claim
17 words
A control system as defined in claim 2 wherein the respective areas of said pistons are equal.
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) | 1981-04-10 | 1981-10-10 | 1982-04-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-04-10 | 1985-10-10 | 1986-04-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-04-10 | 1989-10-10 | 1990-04-11 | $7700.00 | Window Closed / Lapsed |