John S Reece

US Patent:

41375130, Jan 30, 1979

Filed:

Oct 27, 1977

Appl. No.:

5/846082

Inventors:

John W. Reece - Sunnyvale CA
Victor J. Italiano - Ithaca NY
Leslie L. Crump - Trumansburg NY

Assignee:

NCR Corporation - Dayton OH

International Classification:

H01F 716

US Classification:

335219

Abstract:

A matrix print wire solenoid has a small diameter print wire which wire is propelled against printing paper and inking ribbon by the linear motion of the solenoid plunger, to which the print wire is attached, in an improved impact printer having a plurality of solenoids positioned in a row for use in dot matrix printing. The solenoid features a low cost construction, a reduction in size, and increased operating speed, and has pole pieces which are separated by an inner gap and which pieces are aligned with a coil bobbin which provides a guide surface for the armature plunger. The space between the plunger and a forward bushing or spacer is occupied by a coil spring which has one end seated over a portion of the armature and the other end seated against the face of the bushing. The coil bobbin defines an air gap between one pole piece and the armature.