Patent · US Expired

Linear actuator

US6118360A · kind A · utility

47Cited by
32References
17Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMar 16, 1999
Grant dateSep 12, 2000
Priority date
Expiry dateMar 16, 2019

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG05B2219/50109
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A linear actuator includes a plurality of magnetic plates and a ferrite core with a conductive cover which are mounted on the actuator body to generate a permanent magnetic field. The linear actuator also includes a metal bobbin which has an outer surface and which is formed with an aperture that defines an inner surface for the bobbin. Further, the bobbin is formed with a gap which extends along its length and which intersects the bobbin from its inner to its outer surface. An insulating insert is placed in the gap. Finally, a winding is wrapped around the outer surface of the bobbin to form an electromagnetic coil, and the coil on the bobbin is slidingly mounted on the actuator to receive the ferrite core through the bobbin's aperture. Electrical current can then be selectively applied to the winding to interact with the permanent magnetic field and thereby cause reciprocating motion of the coil. Due to the gap in the bobbin, an induced current which would otherwise hinder the desired reciprocating motion of the coil does not form on the outer surface of the bobbin. Due to the conductive cover, the response time of the coil to the applied current is reduced. In this manner, preci…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.