Patent US4481789A successfully refreshed from Google Patents.
US4481789A
Expired / Lapsed
US
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Air conditioner for vehicles
Assignee: Churyo Engineering Co Ltd
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Filing: 1982-03-15
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Granted: 1984-11-13
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Expires: 2002-03-15
Abstract
Abstract An air conditioner for vehicles in which the temperature of an evaporator is detected and an ON-OFF control of the compressor is achieved to maintain the evaporator temperature at a pre-set temperature. The air conditioner has means for detecting the temperature of air flowing into the evaporator, and means for varying the pre-set temperature in such a manner that the pre-set temperature is increased as the detected air temperature is decreased and is decreased as the detected air temperature is increased.
Inventors
- 👤 Ryosaku Akimoto
- 👤 Nobuaki Ito
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 03:26
CPC Classifications
B; B60; B60H; B60H1/00; B60H1/32; B60H1/3204; B60H1/3205; B60H1/3211; B60H1/321; G; G05; G05D; G05D23/00; G05D23/19; G05D23/1927; G05D23/193; G05D23/1931; G05D23/20; G05D23/24; B60H2001/3236; B60H2001/3255; B60H2001/3261; B60H2001/3263; B60H2001/3269; B60H2001/327
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
184 words
An air conditioner for vehicles having means for detecting the temperature of an evaporator and adapted to effect ON-OFF control of a compressor to maintain the evaporator temperature at the same level as a pre-set temperature, characterized by comprising: means for detecting the air temperature of the air flowing into said evaporator; and means for varying said pre-set temperature in accordance with said air temperature such that said pre-set temperature is lowered as said air temperature becomes higher and is made higher as said air temperature becomes lower, said means for varying the pre-set temperature including: an input circuit having two temperature detection elements for detecting the temperature of air flowing into said evaporator and a temperature detection element for detecting the temperature of said evaporator, and adapted to produce a reference voltage V A which increases as the air temperature is increased and a voltage V B which decreases as the evaporator temperature is increased; and a comparator circuit for receiving said voltages V A and V B and adapted to produce an output for effecting an ON-OFF control of said air compressor.
Claim 2
Dependent Claim
184 words
An air conditioner for vehicles having means for detecting the temperature of an evaporator and adapted to effect ON-OFF control of a compressor to maintain the evaporator temperature at the same level as a pre-set temperature, characterized by comprising: means for detecting the air temperature of the air flowing into said evaporator; and means for varying said pre-set temperature in accordance with said air temperature such that said pre-set temperature is lowered as said air temperature becomes higher and is made higher as said air temperature becomes lower, said means for varying the pre-set temperature including: an input circuit having two temperature detection elements for detecting the temperature of air flowing into said evaporator and a temperature detection element for detecting the temperature of said evaporator, and adapted to produce a reference voltage V A which increases as the air temperature is increased and a voltage V B which decreases as the evaporator temperature is increased; and a comparator circuit for receiving said voltages V A and V B and adapted to produce an output for effecting an ON-OFF control of said air compressor.
Claim 3
Dependent Claim
29 words
An air conditioner as claimed in claim 1, wherein said input circuit consists of a bridge circuit including two thermistors constituting said temperature detection elements and other two resistors.
Claim 4
Dependent Claim
48 words
An air conditioner as claimed in claim 1, wherein said voltage V A has an upper limit value V 0 , and means are provided for maintaining said voltage V A at the upper limit level V 0 when the air temperature is higher than a predetermined level.
Claim 5
Dependent Claim
37 words
An air conditioner as claimed in claim 1, wherein said upper limit voltage V 0 is provided by a constant voltage diode connected between a point at which said voltage V A is obtained and the ground.
Claim 6
Dependent Claim
59 words
An air conditioner as claimed in claim 1, wherein a switch is disposed between the point at which said voltage V A is obtained and a positive D.C. voltage power supply, thereby to make it possible to maintain said voltage V A at said upper limit level V 0 regardless of the temperature of air flowing into said evaporator.
Claim 7
Dependent Claim
27 words
An air conditioner as in claim 1, wherein said input circuit comprises a bridge circuit including two thermistors forming said temperature detection elements and two other resistors.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-11-13 | 1988-05-14 | 1988-11-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-11-13 | 1992-05-14 | 1992-11-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-11-13 | 1996-05-14 | 1996-11-13 | $7700.00 | Window Closed / Lapsed |