GB1224697A - Electric driving arrangement using a stepping motor - Google Patents

Abstract

1,224,697. Control of stepping motors. PHILIPS ELECTRONIC & ASSOCIATED INDUSTRIES Ltd. 11 Sept., 1969 [14 Sept., 1968], No. 44945/69. Heading H2J. When a controller ,l0 receives a forward or reverse starting signal, it generates a pulse E which is transmitted to ring counter 3 through gate 4, and sets a bi-stable switch 6 to open a gate 5. Simultaneously, the controller 10 transmits a signal U to the ring counter 3 which commences counting in the desired direction. A stepping motor 1 is accelerated to its next position in which a photo-electric pulse generator 12-14 develops pulse G which is applied to the ring counter through gates 5 and 4. The ring counter further advanced so that the motor moves to its succeeding position. The pulses G are applied to controller 10 to be counted and compared with the number of steps the motor is to travel. A number of steps before the motor reaches the desired stopping position, the controller 10 develops a deceleration pulse F which changes over the switch 6. The next pulse G does not pass through the gate 5 but is applied to a delay circuit 7 which produces a signal T, the delay time of this circuit being greater than the interval between two successive pulses G at this stage. Pulse gate 8 now passes the pulses G through OR- gate 9 and the gate 4 to the ring counter 3 whereby the motor is decelerated since it tends to be retained in its preceding position. When the time between two successive pulses G exceeds the delay time of the circuit 7, the gate 8 is closed and the motor assumes a speed which depends upon the delay time, but it cannot step backward. The controller 10 the develops a signal W to close the gate 4 and stop the ring counter 3, the motor being stopped within a single step.