Patent US3844684A successfully refreshed from Google Patents.
US3844684A
Expired / Lapsed
US
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Preliminary compressor lubricating device
Assignee: Hitachi Ltd
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Filing: 1973-07-31
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Granted: 1974-10-29
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Expires: 1993-07-31
Abstract
Abstract A device for automatically actuating the compressor of an air conditioner for a motor vehicle by the engine of the motor vehicle to effect preliminary lubrication of sliding parts of the compressor upon starting of the engine, in case the engine speed is in a cranking speed range and the open air temperature is above a predetermined level. The device comprises a temperature sensor, an engine speed discriminating circuit and a temperature responsive circuit connected to an AND circuit, and closes a relay and engages an electromagnetic clutch when the engine speed is below 800 rpm and the open air temperature is above 10*C so as to connect the compressor to the engine to render the former operative.
Inventors
- 👤 S Kawamura
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 18:23
CPC Classifications
F; F04; F04B; F04B49/00; F04B49/06; B; B60; B60H; B60H1/00; B60H1/32; B60H1/3204; B60H1/3205; B60H1/3214; F04B39/00; F04B39/02; F04B39/0207; F04B49/10
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
142 words
A device for effecting preliminary lubrication of a compressor of an air conditioner for a motor vehicle adapted to be connected and disconnected to an engine of the motor vehicle through an electromagnetic clutch and provided with means for supplying lubricant to sliding parts of the compressor, comprising an engine speed discriminating circuit connected to an ignition circuit for the engine, a sensor for sensing the open air temperature, an open air temperature responsive circuit adapted to respond to the prevailing open air temperature, and an AND circuit connected to output terminals of the engine speed discriminating circuit and the temperature responsive circuit and producing a signal to a compressor starting relay to close the relay and engage the electromagnetic clutch when the engine speed is a cranking speed or idling speed and the open air temperature is above a predetermined level.
Claim 2
Independent Claim
142 words
A device for effecting preliminary lubrication of a compressor of an air conditioner for a motor vehicle adapted to be connected and disconnected to an engine of the motor vehicle through an electromagnetic clutch and provided with means for supplying lubricant to sliding parts of the compressor, comprising an engine speed discriminating circuit connected to an ignition circuit for the engine, a sensor for sensing the open air temperature, an open air temperature responsive circuit adapted to respond to the prevailing open air temperature, and an AND circuit connected to output terminals of the engine speed discriminating circuit and the temperature responsive circuit and producing a signal to a compressor starting relay to close the relay and engage the electromagnetic clutch when the engine speed is a cranking speed or idling speed and the open air temperature is above a predetermined level.
Claim 3
Dependent Claim
254 words
A device according to claim 1 wherein said engine speed discriminating circuit comprises a filter circuit connected to an ignition circuit of the motor vehicle and including a diode connected to the ignition circuit through a primary ignition pulse take-out line of the motor vehicle, a plurality of resistors and a capacitor, A transistor having a base connected to an output terminal of said filter circuit, a differentiating circuit including a capacitor connected to a collector of said transistor, an integrating circuit including a diode connected to said differentiating circuit, and a Schmitt circuit including a first transistor, a second transistor and a third transistor, said first transistor having a base connected to said integrating circuit and said third transistor having a collector connected to said AND circuit; said open air temperature responsive circuit comprises a Schmitt circuit including a first transistor and a second transistor, said first transistor having a base connected to said temperature sensor and said second transistor having a collector connected to said AND circuit; and said AND circuit comprises a first diode connected to said collector of said third transistor of said Schmitt circuit of said engine, a second diode connected to said collector of said second transistor of said Schmitt circuit of said open air temperature responsive circuit, a first transistor connected to said first and second diodes through a third diode and having a collector connected to a base of a second transistor having a collector connected to a compressor starting relay connected to the electromagnetic clutch.
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) | 1977-10-28 | 1978-04-29 | 1978-10-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-10-28 | 1982-04-29 | 1982-10-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-10-28 | 1986-04-29 | 1986-10-29 | $7700.00 | Window Closed / Lapsed |