Low temperature latching solenoid
US4295111A · kind A · utility
Inventors
Key dates
| Filing date | Nov 29, 1979 |
| Grant date | Oct 13, 1981 |
| Priority date | — |
| Expiry date | Nov 29, 1999 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01F7/124
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
Disclosed is a magnetically latching solenoid including a pull-in coil and a delatching coil. Each of the coils is constructed with a combination of wire materials, including material of low temperature coefficient of resistivity to enable the solenoid to be operated at cryogenic temperatures while maintaining sufficient coil resistance. An armature is spring-biased toward a first position, that may extend beyond the field of force of a permanent magnet. When voltage is temporarily applied across the pull-in magnet, the induced electromagnetic forces overcomes the spring force and pulls the armature to a second position within the field of the permanent magnet, which latches the armature in the pulled-in position. Application of voltage across the delatching coil induces electromagnetic force which at least partially temporarily nullifies the field of the permanent magnet at the armature, thereby delatching the armature and allowing the spring to move the armature to the first position.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.