Browse Prior Art Database

Linear Electromagnetic Print Wire Actuator

IP.com Disclosure Number: IPCOM000040134D
Original Publication Date: 1987-Sep-01
Included in the Prior Art Database: 2005-Feb-01
Document File: 3 page(s) / 47K

Publishing Venue

IBM

Related People

Harris, RH: AUTHOR [+2]

Abstract

A linear electromagnetic actuator for wire matrix impact print mechanisms is described. The actuator has a low mass armature and a design that generates maximum print wire force at the beginning of the stroke. A working gap is at the center of the electromagnetic coil instead of at the end poles, and a simplified structure lends itself to easy automatic assembly. Fig. 1 illustrates a horizontal cross-sectional elevational view taken through a single linear electromagnetic actuator structure. A print wire 1 is attached to a movable armature 2 which is in the form of a soft silicon iron ring of low mass. An insert 3 is molded on either face of the ring armature 2 to act as a guide.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 53% of the total text.

Page 1 of 3

Linear Electromagnetic Print Wire Actuator

A linear electromagnetic actuator for wire matrix impact print mechanisms is described. The actuator has a low mass armature and a design that generates maximum print wire force at the beginning of the stroke. A working gap is at the center of the electromagnetic coil instead of at the end poles, and a simplified structure lends itself to easy automatic assembly. Fig. 1 illustrates a horizontal cross-sectional elevational view taken through a single linear electromagnetic actuator structure. A print wire 1 is attached to a movable armature 2 which is in the form of a soft silicon iron ring of low mass. An insert 3 is molded on either face of the ring armature 2 to act as a guide. The ring 2 and the plastic guide element 3 ride within a bore 12 traversing the center of the electromagnetic coil 9 which is wound on a plastic molded bobbin 13. A stator of soft silicon containing iron is shown as stator 5 in the general form of two L-shaped legs. The L-shaped legs of stator 5 are originally formed in a unitary structure with a small bridge connecting them across the gap where the pole faces 4 on the ends of the L- shaped pieces appear in Fig. 1. Fig. 2 illustrates the fact that the two L-shaped members 5, when viewed end-on, are originally joined by a small bridge of material 11 which is machined away during assembly, thus forming the end faces 4 and separating the two L-shaped legs 5 of the stator.

(Image Omitted)

Stator assembly 5 consists of soft electromagnetically permeable iron or sintered iron and is originally joined in a single piece, as stated. The insert is placed in a mold to be surrounded with thermoplastic in a proper configuration to form a winding bobbin 13 on which the electromagnetic winding 9 may be placed. The center of the stator assembly is then drilled and reamed to a precision diameter. The drilling removes the bridge element 11, shown in Fig. 2, and forms the two opposite pole faces 4 in the stator 5 elements...