Balanced single phase alternating current induction motor
US4387330A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 19, 1980 |
| Grant date | Jun 7, 1983 |
| Priority date | — |
| Expiry date | Sep 19, 2000 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02P1/44
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A single phase alternating current induction type motor is operative at more than one voltage level using the same winding circuitry. The motor has a main winding comprising two serially connected sections similarly formed and physically disposed in slots of a slotted stator core to define a number of primary magnetic poles. A second phase winding, such as a start winding, displaced in phase from the main winding sections, is connected in series with one of the main winding sections and in parallel with the other of the main winding sections. A thermistor is permanently connected in series with the start winding, the thermistor increasing in temperature in response to current flow therethrough to a preselected point where the effectiveness of the second phase winding becomes substantially less than during starting conditions regardless of the operating voltage. In addition, the first phase winding is formed such that at all rated voltage levels of operation, a generally balanced MMF pattern is produced for the primary magnetic poles, both during start and run conditions. To enhance this balance, the two winding sections of the main winding may be bifilarly wound.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.