Patent · US Expired

Print head having a wear resistant rotational fulcrum

US4802776A · kind A · utility

21Cited by
9References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 1, 1987
Grant dateFeb 7, 1989
Priority date
Expiry dateSep 1, 2007

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB41J2/28
  • WIPO fieldTextile and paper machines
  • WIPO sectorMechanical engineering

Abstract

A print head having magnetic members attracted by a permanent magnet while resiliently deflecting resilient members connected to one ends thereof associated with corresponding solenoids adapted to selectively release the associated magnetic members by cancelling the magnetic attracting force of the permanent magnet, so that the magentic member is actuated by the energy stored in the resilient members to drive printing elements into a printing position. To reduce the moment of inertia of the magnetic member, the magnetic pole surface of the permanent magnet or a yoke mounted on the permanent magnet is contacted with one end of the magnetic member to form a fulcrum for the rotation of the magnetic member. The magnetic pole surface of the permanent magnet or yoke on the permanent magnet and at least the fulcrum portion of the magnetic member are provided with hardened wear-resistant layers formed, for example, by plating with nickel, thereby achieving a higher resistance to wear. The wear of the magnetic pole surface of the fulcrum and of the magnetic member are reduced thereby avoiding non-uniformity of the moment of force in the magnetic members, as well as the resilient force in th…

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