JPS6336199U - - Google Patents

Description

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing a case where the stepping motor drive amplifier according to this invention is implemented in a head positioning mechanism of a magnetic disk device, FIG. 2 is a circuit diagram showing the circuit configuration of the stepping motor drive amplifier according to this invention, Figures 3 and 4 are block diagrams showing the configuration of the second amplifier, Figure 5 is a time chart, Figure 6 is a block diagram showing another embodiment of the second amplifier, and Figure 7 is a time chart. , FIG. 8, and FIG. 9 are diagrams showing an example of the conventional method. In the figure, 12 is a winding selection circuit, 14 is a current outflow point of the first winding group, 15 is a current outflow point of the second winding group, 1
6 is a second amplifier, 20 is a switch circuit, 101,
102 is a control transistor, 103 is a common emitter resistor, and 104 and 105 are control amplifiers. Note that the same reference numerals in each figure indicate the same or corresponding parts.

Claims (1)

[Claims for Utility Model Registration] (1) A driving means for sequentially and cyclically passing current through each phase winding of a stepping motor to cause the stepping motor to continuously rotate in a desired rotational direction; A stepping motor drive amplifier comprising a driving means for stopping the stepping motor at an arbitrary angle by adjusting the magnitude of the current flowing through each phase winding of the stepping motor. A winding selection circuit that selects which winding to conduct current with the current inflow ends of the phase windings connected in parallel and connected to the positive terminal of the power supply. Each current outflow point is constructed by connecting the current outflow ends of a pair of windings in parallel to each other, and the current outflow ends of a pair of windings, which do not allow current to flow simultaneously due to the selection of the winding selection circuit described above, are connected to each other, and each collector is connected to each current outflow point. Each control transistor is connected to the connection point where each emitter of each control transistor is connected to each other, and the negative polarity terminal (ground) of the above power supply.
a common emitter resistor connected between each control transistor, each control amplifier connected to apply a respective control voltage to each base of each of the above control transistors, and a common emitter resistor connected between a second amplifier that generates a voltage that varies from one to the other, each of the control transistors being controlled by the output of each of the control amplifiers and connected to operate as a differential amplifier circuit by means of the common emitter resistor; A stepping motor drive amplifier comprising: a switching circuit that switches between short-circuiting and connecting the control transistors so that a saturation current flows through them. (2) The second amplifier is composed of a microprocessor and a digital-to-analog converter, and the microprocessor outputs a digital signal that continuously changes with respect to time. The stepping motor drive amplifier described in Section 1. (3) The stepping motor drive amplifier according to claim 1, wherein the second amplifier is constituted by an incompletely integrating function amplifier inputting a rectangular wave voltage. (4) The stepping motor drive amplifier according to claim 1, wherein the second amplifier inputs the tracking error of the magnetic disk device and generates a voltage that continuously changes with respect to time. .