Hybrid linear actuator
US4845392A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 10, 1983 |
| Grant date | Jul 4, 1989 |
| Priority date | — |
| Expiry date | Mar 10, 2003 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01F2007/163
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A linear actuator is a hybrid in that movement of the armature is influenced by the field of permanent magnets and the field of a coil when it is energized by direct current. The coil is fixed in a ferromagnetic shell and a pair of permanent magnets are fixed in the shell axially of the coil. The armature has a reduced diameter tip or end which is influenced by the magnets when the coil is deenergized and which enables the force on the armature to remain generally uniform over the working stroke of the armature. The linear actuator is shown operating a sleeve valve spring biased to closed position and opened relative to the metering cone by application of direct current to the coil. The effective magnitude of the current determines how much the valve opens.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.