EP 0306437 A3 19901017 - CHOPPER CIRCUIT FOR THE CONTROL OF COILS OF ELECTROMAGNETS OR STEP MOTORS, PARTICULARLY FOR A MATRIX PRINTER
Title (en)
CHOPPER CIRCUIT FOR THE CONTROL OF COILS OF ELECTROMAGNETS OR STEP MOTORS, PARTICULARLY FOR A MATRIX PRINTER
Publication
Application
Priority
DE 3727283 A 19870812
Abstract (en)
[origin: EP0306437A2] Such a chopper circuit is used for controlling electromagnetic and/or stepping motor coils (8; 26), particularly for a matrix printer, whose inductance, in conjunction with the applied voltage, generates a maximum current which is, however, adjusted to be reduced by a desired factor, it being possible to generate the current ripples (7a) by chopping. <??>These current ripples (7a) can now be varied as a function of the frequency, inductance and resistance of an electromagnetic coil (8) or of a magnetic coil winding (26), i.e. they can be optimised. <??>For this purpose, it is proposed that a current measuring device (10) with a current switch-off capability (11) be allocated in each case to a driver circuit (9) for the electromagnetic coil (8) and to a bridge circuit (27) for the stepping motor coil (26) and that digital control logic (12) be provided which generates a control signal (2), synchronised to a frequency transmitter (3) connected upstream, which control signal (2), alternately with the current switch-off device (11), acts as an on or off signal at the input (13) of the driver circuit (9) and of the bridge circuit (27). <IMAGE>
IPC 1-7
IPC 8 full level
H02P 8/12 (2006.01); H01H 47/32 (2006.01)
CPC (source: EP US)
H01H 47/325 (2013.01 - EP US)
Citation (search report)
- [Y] GB 2081942 A 19820224 - EXPLORATION LOGGING INC
- [X] EP 0087583 A1 19830907 - IBM [US]
- [A] EP 0212462 A2 19870304 - BSO STEUERUNGSTECHNIK GMBH [DE]
- [X] IBM TECHNICAL DISCLOSURE BULLETIN. vol. 27, no. 2, Juli 1984, NEW YORK US Seiten 1057 - 1058; W. Renz and H. Virag: "CLOCKED MAGNET DRIVER"
Designated contracting state (EPC)
AT BE CH DE FR GB IT LI NL
DOCDB simple family (publication)
EP 0306437 A2 19890308; EP 0306437 A3 19901017; DE 3727283 A1 19890223; DE 3727283 C2 19930617; JP S6464598 A 19890310; US 4989116 A 19910129
DOCDB simple family (application)
EP 88730168 A 19880728; DE 3727283 A 19870812; JP 20184388 A 19880812; US 23231188 A 19880812