Solenoid device with stable activation
US8416041B2 · kind B2 · utility
Inventor
Key dates
| Filing date | Aug 19, 2011 |
| Grant date | Apr 9, 2013 |
| Priority date | — |
| Expiry date | Aug 19, 2031 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01F7/1607
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A solenoid may include a core having a junction surface; a plunger having a junction surface and located adjacent to the core; a shading ring located proximate to an interface between the core junction surface and the plunger junction surface, the shading ring having an outside diameter slightly smaller than the diameter of the core, and operable to produce a concentration of magnetic attraction within an annular range of the interface between a center of the interface and a location of the shading ring; wherein a contact region between the core junction surface and the plunger junction surface is substantially smaller than the respective junction surfaces and located proximate to the annular range of the concentration of magnetic attraction.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.