GB1280067A - Improvements in or relating to printing machine control arrangements - Google Patents

Abstract

1280067 Stepping motor control POLYGRAPH LEIPZIG KOMBINAT FUR POLYGBAPHISOHE MASCHINEN UND AUSRUSTUNGEN VEB 5 June 1970 27311/70 Heading H2J [Also in Division B6] Stepping motors M, having respective windings a-b, c-d, connected to control outputs y 1 -y 1 , y 2 -y 2 perform complete revolutions in response to an input pulse X, Fig. 9. The two windings are energized at once and current in them is sequentially reversed for stepping by 90 degree intervals. In Fig. 9, line B is normally at a potential L, and A at zero potential, with outputs y 1 , y 2 energized. A pulse at X gives a potential at A through " AND " gate 30, and " OR " gate 31 which passes through " AND " gate 39 back to 31 to render the potential A stable until the potential at B changes. The potential at A also passes through amplifier 32 and interchanges the potentials at y 1 , y 1 with the help of " NOT " gate 33, and after a delay provided at 34 passes through amplifier 35 to similarly interchange the potentials at y 2 , y 2 . After a further delay at 37 the signal causes " NOT " gate 38 to change its state, so that the potential at B goes to zero, causing the potential at A to go to zero, and be held as before by the operation of gates 31, 39. The change in potential at A causes y 1 and y 1 to interchange, followed sequentially by y 2 , y 2 in the manner described above, and after a further delay the potential at B again rises and the circuit is sensitive to further pulses at X, the motors having made one revolution in four steps. The input of control network 29 may be connected to a monostable multivibrator (40) Fig. 10 (not shown) to give a pulse of definite duration, or to an adjustable astable multivibrator (42), Fig. 11, (not shown), for continuous operation, or the multivibrator (42) may be incorporated in a circuit having an " AND " gate (43), a " NOT " gate (45) and a counter (44) Fig. 12 (not shown) so that a determined number only of pulses passes to 29, the potential at (C) disappearng after the required pulse count is reached. Fig. 13 shows a switching network for a set of stepping motors in each one of a number of inking devices in a printing press, motors M1.1.1, 1.1.2-MX.1.1- X 1.2, being in locations 1-X in one inking device, and motors M1.1.1,1.1.2-M1.X.1-1.X.2 being in corresponding locations in successive inking devices. Switches DA1-DAX connect one side of the windings of all the motors in inking devices 1-X to the control 29, and switches SA1-SAX similarly connect corresponding motors in position 1-X in each inking device, so that motors in given locations in a selection of the inking devices can be energized. The motor windings may be coupled to a pulse counter 6, Fig. 15, (not shown), or an indicating disc (49), Figs. 16, 17 (not shown), may be fitted. Indicating motors may be fitted on a control panel. Applications of stepping motors to a printing press, see Division B6, are given, Figs. 1-8, 18 (not shown).