Method and apparatus for monitoring a transport refrigeration system and its conditioned load
US4949550A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 4, 1989 |
| Grant date | Aug 21, 1990 |
| Priority date | — |
| Expiry date | Oct 4, 2009 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF25B2600/23
- WIPO fieldOther consumer goods
- WIPO sectorOther fields
Abstract
A monitor for a transport refrigeration unit in which the temperature of the air discharged by the unit into a load space is compared with the temperature of air returning to the unit, to provide a signal DI responsive to the algebraic difference. Signal DI, which represents the actual conditioning mode, is compared with a commanded conditioning mode signal provided by a thermostat associated with the transport refrigeration unit, and also with predetermined reference values, to detect incorrect operating modes, as well as significant loss of refrigerant capacity. Timers initiate resettable time delays in response to such detections, after which warning and shut-down signals are respectively provided when certain time delays are allowed to expire. Logic signals provided by the monitor are logically related when the monitor shuts the system down to drive diagnostic display which indicates the cause of shut down.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.