PSC motor start system
US5053908A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 29, 1989 |
| Grant date | Oct 1, 1991 |
| Priority date | — |
| Expiry date | Nov 29, 2009 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01H2061/004
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A motor winding system having a main winding and a start winding circuit with a start winding and a PTC resistor in series therewith wherein the resistor is electrically removed from the circuit at a predetermined time after motor starting and remains in this state until motor shut off. The start winding circuit also includes a bimetallic switch in series with the resistor and a series circuit of a capacitor and an electromagnet in parallel with the resistor and switch. At motor start up, current from the main power source is applied across the main winding and the start winding circuit heats up the resistor and causes an increase in the resistance thereof. Also, current through the switch and PTC heat causes the bimetallic element to snap or move when it has reached a predetermined temperature to open the start winding circuit. Meanwhile, low current passes through the capacitor and electromagnet winding, energizing the electromagnet and causing the bimetallic element to be attracted and latched to the electromagnet after predetermined movement.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.