EP 0384095 B1 19930901 - MATRIX NEEDLE PRINTHEAD OF THE PRE-TENSED TYPE
Title (en)
MATRIX NEEDLE PRINTHEAD OF THE PRE-TENSED TYPE
Publication
Application
Priority
EP 89730039 A 19890220
Abstract (en)
[origin: EP0384095A1] A matrix needle print head, in particular of the pretensioned design, has a baseplate (1) of low-retentivity material, an annular permanent magnet (2), a spacing ring (3), a spring (4) which is radially outwardly clamped in each case and to which an armature body (6) is attached and can be pretensioned in each case against the core (7) of an electromagnetic coil (8) arranged in each case on the baseplate (1), it being possible to eliminate the magnetic flux generated by the permanent magnet (2) by supplying the electromagnetic coil (8) with current and it being possible to push the armature body (6), to which a printing element (4a) is attached, against a recording carrier and, if appropriate, a secondary magnetic flux circuit being formed to the main magnetic flux circuit (9) formed via the permanent magnet (2) via a short-circuit body. <??>In order to avoid a power-reducing influencing of adjacent electromagnetic coils by their magnetic fields, it is proposed according to the invention to surround each electromagnetic coil (8) on its circumference (8a) partially or completely with low-retentivity materials (11). <IMAGE>
IPC 1-7
IPC 8 full level
B41J 2/28 (2006.01)
CPC (source: EP US)
B41J 2/28 (2013.01 - EP US)
Designated contracting state (EPC)
AT BE CH DE FR GB IT LI NL
DOCDB simple family (publication)
EP 0384095 A1 19900829; EP 0384095 B1 19930901; AT E93773 T1 19930915; DE 58905472 D1 19931007; JP H02292051 A 19901203; US 5073051 A 19911217
DOCDB simple family (application)
EP 89730039 A 19890220; AT 89730039 T 19890220; DE 58905472 T 19890220; JP 3129090 A 19900209; US 48116690 A 19900220