Automatic air conditioning system with variable displacement compressor, for automotive vehicles
US4894999A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 30, 1989 |
| Grant date | Jan 23, 1990 |
| Priority date | — |
| Expiry date | Mar 30, 2009 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF04B2207/03
- WIPO fieldTransport
- WIPO sectorMechanical engineering
Abstract
An automatic air conditioning system for automotive vehicles with a variable displacement compressor comprises a sensor for detecting an intake air temperature of air flowing through the evaporator placed just behind the evaporator, a control valve for the compressor essentially changing the discharge of said compressor on the basis of the difference between the intake air temperature and its target value, and a CPU for changing the target value of the intake air temperature. When the CPU does not receive a signal indicative of a requirement for quick-cooling, the target value is set to a freezing start possible temperature defined by an intake air temperature such that the freezing of the evaporator starts, and when the CPU receives the signal indicative of a requirement for quick-cooling, the target value is set to a predetermined temperature lower than the freezing start possible temperature. Thus, the automatic air conditioning system is capable of maintaining a high displacement of refrigerant in spite of the lowering of suction pressure of the compressor, related to the dropping of the intake air temperature, when the quick-cooling is required.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.