SU1444929A1 - Power amplifier for stepping motor control - Google Patents

Abstract

The invention relates to the field of electrical engineering and can be used to control the stepper motor time meters and electric clocks. The purpose of the invention is to increase reliability by limiting the voltages on the winding of a stepper motor. The device has two circuits, each of which consists of two last, - connectedly connected bipolar transistors 1 and 2 of the same conductivity type and a diode 3 connected between them. The collectors of the transistors 1 of both control circuits are connected via a resistor to the power bus, and the emitters of the transistors 2 are connected directly to the other power bus. The winding of the stepping motor 6 is connected to the emitters of transistors 1 of each control circuit, and parallel to it are connected in series and oppositely directed diodes 7 and 8, between which the junction point and collectors of transistors 1 are connected to Zener diode 9. There are pulses for controlling the device podgiots to the bases of transistors 2. 1 il.

Description

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The invention is relative / Oi to electric power machines and can be used in the electric drive of watch mechanisms, counters and mechanisms

The purpose of the invention is to increase reliability by limiting the voltages on the winding of a stepper motor.

In the drawing, an electrical circuit diagram of a power amplifier is shown.

The device contains two circuits, each of which consists of two series-connected bipolar transistors I and 2 of the same conductivity type and a diode 3 connected between 1 SHMI. The co-collectors of the transistors 1 of both circuits are connected via a single power supply bus across the resistor 4, and the emitters of the transistors 2 are connected directly to the other power supply bus. The bases of the transistors I are connected to the collectors of the transistors 2 and, through resistors 5, to the first power rail. The winding b of the stepper motor is connected to the emitters of the transistors 1 of each control circuit, and parallel to it are connected serially connected and oppositely directed diodes 7 and 8, between which the CO-junction point and collectors of transistors 1 are connected to a stabilizer ;-ron 9.

The input pulses for the control device are fed to the bases of the transistors 2.

The voltage is supplied from the power supply bus through a resistor 4 to the collectors of transistors 1, and through resistors 5 to their bases and collectors of transistors 2.

In the initial position, when there are no input pulses, at the bases of transistors 2 there is a positive level of voltage that keeps these transistors open in the open state. At the same time, the current flows through the following circuit: the first power bus, resistor 4, zener diode 9, diodes 7 and 8, diode 3, collector-ekstterter transistors 2, the second power bus. Due to the voltage drop across the diodes 3, the transistors 1 are in the closed state. There is no voltage on the winding of the stepper motor b, since the current passing through the diodes 7 and 8 has the same magnitude and the opposite voltage. When current flows through diodes 7 and 8, the last

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on; OAJA.Ts in open condition, shunt those; Sagam winding 6 stepper motor.

When the control pulse arrives at the base of transistor 2, this transistor locks and transistor 1 of the same circuit is unlocked. In this case, the current flows through the following circuit; the resistor 4, the collector-emitter of the transistor 1, the winding 6 of the stepping motor, the diode 3 and the collector-emitter of the transistor 2 of another circuit. In addition, a portion of the current after resistor 4 branches off, passing through Zener diode 9 and diode 8, creating a voltage drop across them. This voltage remains stable when the voltage on the power supply tires changes. Winding 6 stepper motor connected; : - -P iri le .- b but a chain of Zener diode 9 and diode 8 Chers: 3 open transistor collector-emitter of transistor Ciopa I. As a result of this: amg: the voltage across the winding 6 of the stepping motor is not dependent on the voltage variation on the power supply screws. After removing the control pulse, the device returns to its original position and the diodes 7 to B shunt the winding 6 of the stepping motor. On entering: the control pulse across the circuit, the processes in the device proceed in the same way, and the current through the winding b stepper motor is reversed.

Thus, pulses of alternating polarity and stabilized amplitude are formed in the winding of a stepper motor, and in the pause between them, the winding is short-circuited, thereby ensuring reliable operation of the stepping motor.

Claims (1)

Invention Formula A power amplifier for controlling a stepper motor, containing two circuits, each of which consists of two series-connected bipolar transistors of the same conductivity type and a diode connected between the transistors, the collectors of the first transistors of both circuits are connected through a resistor to the first power bus, the emitters of the second transistors are directly second, the stepper motor winding is connected to emitte31444929 frames of the first transistors, and the base of the gatekeeper, introduced a Zener diode and two These transistors are a control diode, connected in series with power amplifier inputs, t-counter and connected to the winding, which is stitched by the stepping motor, and the zener diode is switched by reliability between the connection point of the diodes and voltage across the winding dvi-resistor.