Patent · US Expired

Electromagnetic actuator

US4945331A · kind A · utility

1Cited by
2References
7Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJul 25, 1989
Grant dateJul 31, 1990
Priority date
Expiry dateJul 25, 2009

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB41J9/38
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

An electromagnetic actuator for driving a hammer of an impact printer includes a solenoid and an armature which is attracted thereby. In a state of standby for printing, no current is supplied to the solenoid, and the armature holds the hammer in an urge-accumulated state. Upon supply of a current to the solenoid, the armature is attracted toward the core, and the hammer head in that state is released so as to be impacted against a platen, thereby effecting a printing operation. If the current is shut off with the armature attracted by the core of the solenoid, the armature returns to its original position. To effect a speedy return at that juncture, a return leaf spring having a resilient bent portion is interposed between the core and the armature.

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