Abstract: A circuit for controlling nozzle heads in inkjet printers includes a first plurality of nozzles disposed in a row forming an angle relative to a horizontal and to a line direction, respectively, wherein the nozzles of the first plurality of nozzles exhibit a defined distance from each other, and wherein the nozzles of the first plurality of nozzles are to be shot off without a time delay, and a second plurality of nozzles disposed in the row forming the angle relative to the horizontal and to the line direction, respectively, and electronically distinguished from the first plurality of nozzles, wherein the nozzles of the second plurality of nozzles exhibit a defined distance from each other, and wherein the nozzles of the second group of nozzles are disposed interleaved relative to the first plurality of nozzles.

Abstract: An apparatus to regulate the speed of pulse width modulated electric motors 1 has a coder 3 on the shaft 2, the signals from which are used as feedback signals in the regulation circuit, and are transmitted to a regulator 4 with a microprocessor 5, from the output control lines 6, 7 to an amplifier 8, and the amplifier 8 feeds the electric motor 1.To reduce the quantity of hardware components of the regulator 4, and in particular to save time in the CPU even at relatively low setpoint speeds, and to achieve a more rapid and more precise regulation overall, the invention proposes that the regulator 4 comprises a microprocessor 5 connected to the coder 3, wherein the microprocessor 5 is connected by means of a data and address bus 9 to a peripheral control component 10, and that the microprocessor 5 can be loaded by means of the data and address bus 9 with programs 11 for regulating the "off" time of the pulse curve.

Abstract: A switching signal, either for the switching off of the print head (20), or for a lowering of the operating frequency, or for a switching-on/switching-off control of a blower motor, is employed in connection with an installation of a temperature surveillance of a print head (20) or of a hammer block based on an electromagnetic coil construction. In order to achieve a more precise, a quicker and a more individual measurement determination, the electromagnetic coil (3), coordinated to each print element (1), is in each case switched during a current-passing pause to a primary constant current source generating a voltage (U.sub.p). A coil voltage drop (U.sub.s) at the electromagnetic coil (3) generates a reference signal (26) at the comparator (27) setting the temperature limit. The reference voltage (U.sub.ref) is received as a binary logic signal in an intermediate data memory storage (30).

Abstract: A drive system for printers, in particular for matrix printers of a needle-type construction or hammer-type construction, exhibits an electromagnetic coil (L) coordinated to each printing element (6), as well as a magnetizable armature disposed opposite to each electromagnetic core (2), where the print element (6) is attached to the magnetizable armature, where the armature, in case of switched-off electromagnetic coil (L), is maintained in a rearward launching position, and where during a current-passing electromagnetic coil (L) the armature is launched with the print element (6) into a forward-disposed print position.

Abstract: A chopper circuit is provided for driving of electromagnets and/or step motor coils (8;26) in particular for a matrix printer, where the inductivity of the coil generates in connection with the applied voltage a maximum current, which current, however, is set lower by desired factor, whereby the current ripples (7a) are generated by chopping. These current ripples (7a) can be changed, that is, set to an optimum value depending on frequency inductivity and resistance of an electromagnetic coil (8) or, respectively, of a magnet coil winding (26).

Abstract: A d.c. motor is controlled by means of current pulses; each pulse ends by and in synchronism with an optical disk pulse. The period between respective two pulses is referenced to a particular period for determining the sign of a speed derivation, and the result is used to change the length of the pause between two current pulses for the motor. Digital counters are used for time-metering purposes and selection of the pause length between current pulses.

Abstract: The drive circuit for an electromagnetic actuator for the impact element in a printer includes a series circuit of a drive transistor and of a switching transistor there being a reference resistor interposed which together with a Zener diode serves as a current limiter for the current through the drive transistor and the electromagnetic element. The two transistors are controlled in that each of the base electrodes is serially connected to the emitter collector path of a control transistor and the two control transistors in turn are connected to monostable multivibrators which are triggered concurrently but furnish pulses of different duration such that the switching transistor is turned off before the drive transistor. The current limiting permits utilization of residual electromagnetic energy from the preceding actuation pulse without incurring undue losses.

Abstract: A pivoted ink ribbon guide in front of a matrix print head is positioned by a lever linkage which translates the four different combinations of energization stages of two solenoids into four different alignment positions for a multi-colored ink ribbon.