Indicating refrigerant liquid saturation point
US4841734A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 12, 1987 |
| Grant date | Jun 27, 1989 |
| Priority date | — |
| Expiry date | Nov 12, 2007 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB60H2001/3277
- WIPO fieldTransport
- WIPO sectorMechanical engineering
Abstract
A refrigerant control system employing a "self-heated" thermistor disposed in the high pressure refrigerant line to sense refrigerant temperature from the condenser as it enters the expansion valve or capillary. The voltage drop is detected across a resistor in series with the thermistor and converted to saturation pressure from known refrigerant properties. A microprocessor de-energizes the compressor and turns on the condenser fan when excessive saturation pressure is detected. An optional second thermistor senses actual refrigerant temperature for comparison with the saturation temperature to determine sub-cooling and the microprocessor disables the compressor in the event of excessive or insufficient sub-cooling.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.