Richard L. Wagner
Architects in Bellevue, WA
License number
Oregon 3711
Issued Date
Feb 16, 1996
Expiration Date
Dec 31, 2015
Category
Architecture
Address
Address
Bellevue, WA 98004
Professional information
Segmented-Ring Magnet Print Head
US Patent:
4225250, Sep 30, 1980
Filed:
Oct 10, 1978
Appl. No.:
5/949876
Inventors:
Richard E. Wagner - Bellevue WA
Verivada Chandrasekaran - Kirkland WA
Edward D. Bringhurst - Seattle WA
Verivada Chandrasekaran - Kirkland WA
Edward D. Bringhurst - Seattle WA
Assignee:
Tally Corporation - Kent WA
International Classification:
B41J 312
US Classification:
400124
Abstract:
A print head for a serial dot matrix printer comprising a sandwich structure including a base plate, a segmented-ring magnet, a print hammer disc and face plate is disclosed. The segmented-ring magnet comprises a ring formed of a magnetic material having spaced apart, magnetized, regions (segments). The print hammer disc is formed of a magnetically permeable, resilient material and has a plurality of inwardly projecting arms (hammers), each of which is aligned with a magnetized segment. Mounted on the hammers are print blades, which are aligned with radial slots formed in the face plate. Each print blade includes a dot-printing tip that projects orthogonally outwardly from the blade, and lies in a central aperture in the face plate. Mounted on the base plate, in line with each hammer, is a post having a coil mounted thereon. When the coils are de-energized, the magnetic field formed at the tips of the posts is adequate to overcome the spring force of the related hammer, whereby the air gap therebetween is closed and the hammer is cocked.