| 摘要 |
A circuit arrangement for an asynchronous motor drive of controlled stepping, i.e. for control of the number of revolutions of asynchronous squirrel-cage motors, in which the output of the supply unit is connected to a potentiometer, the other terminal of which is connected to the common terminal of the abjusting resistors. The non-common terminal of one of the resistors is connected to one of the inputs of a switch-inductance, whereas the collector of a transistor is connected to the other input. The emitter of the transistor is connected to the negative pole of the supply unit, while one switching point of the switch-inductance is connected to one of the inputs of the NAND-gate having several inputs. There is a magnetic coupled control coil arranged in the system being common for the switch-inductance and the uncoupling coil, while there are as many circuits of identical layout consisting of the switch-inductances, the single abjusting resistors and the transistors, as the number of pulses required for the control. The NAND-gate is connected through a switch-amplifier to the control input of the inverter. |
