Control apparatus for two-speed, single phase compressor
US3978382A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 16, 1974 |
| Grant date | Aug 31, 1976 |
| Priority date | — |
| Expiry date | Dec 16, 1994 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01H50/323
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
The disclosure describes a refrigerant compressor of the type driven by a single phase motor capable of operating at a low speed and a high speed, the motor including a run winding, a 2-pole start winding and a 4-pole start winding. First and second temperature sensors are located adjacent the windings for detecting any change in temperature of the windings. A current transformer is used in combination with the temperature sensors to protect the motor windings. If the temperature or current conduction of any of the windings exceeds a predetermined value, a control device operates a switch in a pilot circuit that turns off the motor before damage from excessive heat or current can occur. A unique contactor assembly utilizing both electrical and mechanical interlocks interconnects the windings to provide two speed operation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.