Starting device and circuit for starting single phase motors
US5561357A · kind A · utility
Inventor
Key dates
| Filing date | Apr 24, 1995 |
| Grant date | Oct 1, 1996 |
| Priority date | — |
| Expiry date | Apr 24, 2015 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02P1/44
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An auxiliary capacitance starting device is connected by only two wires to a capacitor start-induction run (CSIR) or permanent split capacitor (PSC) motor. The device includes an auxiliary start capacitor and an electro-mechanical switching relay that has a current sensing coil wound over a voltage sensing coil and a set of normally closed contacts. The relay is energized first by a current level (amperage) and then latches into an energized mode by voltage, necessarily in that order. The auxiliary start capacitor is electrically connected to the motor circuit in parallel to the start and run winding by two non-polarized leads and in series with the current sensing coil. The voltage sensing coil is connected across the normally closed contacts and senses no voltage as long as the contacts are closed. As the motor gains speed (RPM), the current (amperage) increase through the current sensing coil and when it reaches a preset threshold, the current sensing coil opens the contacts which have a voltage across them when opening which voltage is sensed by the voltage sensing coil of the relay and latches the relay contacts open until power to the motor is removed. The components and circ…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.