Printhead which minimizes stray magnetic flux

Details Printhead which minimizes stray magnetic flux Printhead which minimizes stray magnetic flux

1987-11-16

1989-11-14

Wiecking, David A.

Printing

Selective or progressive

Bed and platen machines

101 9329, 400121, 4001572, B41J 310

Patent

active

048799475

ABSTRACT:
A dot matrix type printer head in which delays in the release of print hammers are eliminated by providing release coils only in alternate hammer positions, or alternatively, activating at one time only release coils in one of even-numbered and odd-numbered hammer positions. A rear yoke and a permanent magnet affixed to a lower leg of the rear yoke are provided in common for all hammer positions. An upper leg of the rear yoke is divided into a plurality of pole pieces. Hammer elements are provided having lower ends rigidly affixed to the rear yoke at positions adjacent the permanent magnet and upper ends retractable against pole faces of corresponding pole pieces by the magnetic force of the permanent magnet. In a first preferred embodiment of the invention, release coils are provided around only even-numbered or odd-numbered pole pieces. In a second preferred embodiment, release coils are provided around all pole pieces, but only release coils in even-numbered or odd-numbered hammer positions are driven simultaneously. In either case, stray magnetic flux which causes a delay in the release of a print hammer interposed between two previously activated print hammers is eliminated.

REFERENCES:
patent: 3941051 (1976-03-01), Barrus et al.
patent: 4033444 (1977-07-01), Beery
patent: 4044668 (1977-08-01), Barrus et al.
patent: 4280404 (1981-07-01), Barrus et al.
patent: 4386563 (1983-06-01), Farb
patent: 4513661 (1985-04-01), Melissa et al.

Affiliated with

Also associated with

Rating

Printhead which minimizes stray magnetic flux does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Printhead which minimizes stray magnetic flux, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Printhead which minimizes stray magnetic flux will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-1847082