JPH01238480A - Motor stop device - Google Patents

Abstract

PURPOSE:To add the stopping function of a motor without providing an exclusive terminal for stopping the motor by detecting that a signal exceeding the output signal range of a speed detector is input as a stop command signal thereby to stop the motor. CONSTITUTION:A motor speed detector 30 is limited in its output signal range to a predetermined level. A stop command detector 40 detects that a signal exceeding the output signal range of the detector 30 is present as a stop command signal at the output of the detector 30. The stop command signal is generated by forcibly setting a terminal 80 to a low level. A conduction switching circuit 26 stops a motor by the output of the detector 40.

Description

[Detailed description of the invention] Industrial applications The present invention relates to a motor stopping device.

BACKGROUND OF THE INVENTION In recent years, recording/reproducing devices using magnetism or light have become increasingly multifunctional, and motors installed in these devices are required to have higher added value. When creating high added value, elemental technologies such as circuit technology, including IC, are essential, and IC
Functions such as stopping the motor can be easily and inexpensively added.

As a conventional technique for stopping a motor, the simplest method is to stop power supply to the motor when a stop command signal is input.

A conventional motor stopping device will be described below with reference to the drawings.

FIG. 2 is a circuit diagram of a conventional motor stopping device.

In FIG. 2, reference numerals 1 to 3 indicate motor drive coils, one end of each of which is commonly connected. The drive coil 1
The other end is grounded through a series circuit of a capacitor 4 and a resistor 5, and is also connected to the collectors of drive transistors 11 and 14. The other end of the drive coil 2 is grounded through a series circuit of a capacitor 6 and a resistor 7, and is also connected to the collectors of drive transistors 12 and 15. The other end of the drive coil 3 is grounded through a series circuit of a capacitor 8 and a resistor 9, and is also connected to the collectors of drive transistors 13 and 16. The emitters of the drive transistors 11 to 13 are commonly connected to the positive power supply line, and the emitters of the drive transistors 14 to 16 are commonly grounded via a resistor 17. Reference numerals 20 to 22 are position detectors for the movable element, each of which has a common positive input electrode connected to the positive power supply line via a resistor 18, and a common negative manual electrode connected to the ground via a resistor 19. . Each output electrode of the position detectors 20-22 is connected to the human power of amplifiers 23-25, respectively, and each output of the amplifiers 23-25 is inputted to an energization switching circuit 26, respectively. The output of the energization switching circuit 26 is connected to the drive transistors 11 to 1.
6 bases.

Here, each of the components 11 to 26 is the motor driving means 1.
It constitutes 0.

On the other hand, 60 is a frequency generator, which is connected to a terminal 70 via a series circuit of a capacitor 61 and a resistor 62, and the terminal 70 is connected to an inverting input of a differential amplifier 131. The non-inverting input of the differential amplifier 131 is connected to resistors 138 and 139.
The output is connected to terminal 80.

A parallel circuit of a capacitor 64 with a resistor 63 is inserted between the terminals 70 and 80. The output of the differential amplifier 131 is connected to one input of a phase difference detector 53 via a comparator 51 having hysteresis. The phase difference detector 53
The other input of is connected to the reference oscillator 52. The output of the phase difference detector 53 is input to the energization switching circuit 26 via a buffer circuit 54.

Here, each of the components 51 to 54 constitutes a torque command signal generator 50.

Further, 100 is a stop command signal input terminal, and the terminal 100 is connected to a non-inverting input of a comparator 101 whose inverting input is biased to a reference power source 102.
The output is input to the energization switching circuit 26.

The operation of the conventional motor stopping device configured as described above will be described below.

In FIG. 2, when the input signal to the stop command signal input terminal 100 is High compared to the reference power supply 102, the comparator 1
The output of 01 becomes High. At this time, it is assumed that the energization switching circuit 26 operates to drive the motor normally.

On the other hand, the speed of the motor is detected by a frequency generator 60, and the detected speed signal is amplified and then input to the input of a comparator 51, that is, the torque command signal generator 50, and the output of the torque command signal generator 50 is energized. It acts on the switching circuit 26 to control the motor drive torque. As a result, the motor is controlled to a constant speed.

Here, the reference power supply 102 is connected to the stop command signal input terminal 100.
If a low signal is input to comparator 1, then comparator 1
The output of 01 becomes Low, and at this time the energization switching circuit 2
6 is assumed to operate to stop driving the motor, the power supply to the motor is stopped and the motor is stopped.

Problems to be Solved by the Invention However, in the above configuration, a dedicated terminal for inputting a stop command signal], OO is required, and the IC of the circuit is
This will lead to an increase in the number of terminals.

Increasing the number of terminals is disadvantageous in terms of price, and increasing the number of terminals by adding a relatively simple motor stop function as described above is not very efficient when trying to increase the added value of motors by using ICs. This is not a good method.

In view of the above-mentioned problems, the present invention provides a motor stopping device that does not provide a dedicated terminal for inputting a stop command signal, but uses terminals for other functions, and allows input of a stop command signal. .

Means for Solving the Problems In order to solve the above problems, a motor stopping device of the present invention includes a multi-phase motor drive coil, a motor drive means for sequentially energizing the drive coils and applying a drive torque to the motor. , a motor speed detector whose output signal range is constrained within a predetermined level, and detecting that a signal exceeding the output signal range of the speed detector is input as a stop command signal to the output of the speed detector. A stop command detection circuit and an output of the stop command detection circuit are configured to stop the supply of driving torque to the motor of the motor driving means.

Effect of the present invention With the above-described configuration, by inputting the motor stop command signal from the output terminal of the speed detector, it is possible to add a motor stop function without increasing the number of terminals, and in particular, by using an IC. It is possible to not only reduce the price but also efficiently increase the added value of the motor.

EXAMPLE Hereinafter, a motor stopping device according to an example of the present invention will be described with reference to the drawings.

FIG. 1 shows a circuit diagram of a motor stopping device according to an embodiment of the present invention.

In FIG. 1, parts having the same functions as those of the conventional motor stopping device shown in FIG. 2 are designated by the same reference numerals, and their explanations will be omitted.

One end of the frequency generator 60 is grounded, and the other end is connected to a terminal 70 via a series circuit of a capacitor 61 and a resistor 62, and the terminal 70 is connected to a non-inverting input of the differential amplifier 31. The inverting input of the differential amplifier 31 is connected to a resistor 38.39.
The output is connected to the base of transistor 32.

The emitter of the transistor 32 is connected to the base of a transistor 33, and the emitter of the transistor 33 is grounded. The collectors of the transistors 32 and 33 are commonly connected to the cathode of a diode 34. The anode of the diode 34 is connected to the resistor 35 and the diode 3.
6.37 to the positive feed line, and the anode of the diode 34 is connected to the terminal 80. A parallel circuit of a resistor 63 and a capacitor 64 is inserted between the terminals 70 and 80.

Here, each of the components 31 to 3 constitute a speed detector 30, and the terminal 80 is connected to the output of the speed detector 30.

The output of the speed detector 30 is transmitted to a torque command signal generator 50.
is input to the energization switching circuit 26 via
The collector of 1 is grounded.

The emitter of the transistor 41 is connected to the base of a transistor 42, and the emitter of the transistor 42 is connected to the positive power supply line via a constant current source 43 and grounded via diodes 44-46. Note that the ground side of the diodes 44 to 46 is a cathode, and the emitter side of the transistor 42 is an anode.

The collector of the transistor 42 is grounded via a resistor 47 and connected to the base of a transistor 48 whose emitter is grounded, and the collector of the transistor 48 is connected to the positive feed line via a constant current source 49. It is input to the energization switching circuit 26.

Here, each of the components 41 to 4 constitute a stop command detection circuit 40.

The operation of the motor stopping device configured as above will be described below.

In Figure 1, when the motor is normally driven,
At the output of the speed detector 30, that is, at the terminal 80, a signal having a frequency corresponding to the speed of the motor is generated. Based on this signal, the torque command signal generator 50 transmits a torque command signal necessary for driving the motor at a constant speed to the energization switching circuit 26, and the speed of the motor is controlled.

Here, due to the configuration of the speed detector 30, the voltage level of the signal generated at the terminal 80 is the sum of the base-emitter voltage of the transistor 33, the collector-emitter saturation voltage of the transistor 32, and the forward voltage of the diode 34. It will not drop below VL.

VL is approximately equal to twice the forward voltage of the diode,
It is about 1.5V.

On the other hand, the terminal 80 is connected to the stop command detection circuit 40, and therefore a voltage higher than VL (=1.5V) is always applied to the base of the transistor 41 forming the input thereof. As a result, the transistor 42 does not become conductive, so the transistor 48 is turned off, and its collector output, that is, the output of the stop command detection circuit 40 becomes High. The output of the stop command detection circuit 40 is Hi
If it is assumed that the energization switching circuit 26 normally operates to drive the motor when g h, the motor continues to be driven while being controlled at a constant speed.

Next, when the terminal 80 is forcibly set to Low by an external signal, the stop command detection circuit 40 determines that a stop command signal has been input, and sends a signal to the energization switching circuit 26 to stop driving the motor. Output. That is, when the base voltage of the transistor 41 becomes Low (ΣOV), the transistor 42 becomes conductive, the output current of the constant current source 43 turns on the transistor 48, and its collector output becomes Low. Therefore, the output of the stop command detection circuit 40 becomes Low, and at this time the energization switching circuit 26 operates to stop the power supply to the motor and stop the motor.

As described above, according to this embodiment, the output range of the speed detector 30 is restricted to VL (=1.5V) or more during normal motor drive, and the motor speed signal is processed in the output range of VL or more. On the other hand, when the motor is stopped, the following Low voltage (=OV) is forcibly applied to the output of the speed detector 30 as a stop command signal, and this is used to detect the stop command. By configuring the circuit 40 to detect and stop the motor, it is possible to add a motor stopping function without providing a dedicated terminal for stopping the motor, that is, without increasing the number of terminals.

Effects of the Invention As described above, the present invention provides a speed detector for a motor whose output signal range is restricted within a predetermined level, and a signal exceeding the output signal range of the speed detector that is used as a stop command signal to the speed detector. A stop command detection circuit is provided to detect input to the output of the speed detector, and the motor is stopped by the output of the stop command detection circuit, so that the output terminal of the speed detector and the stop command signal input terminal are It made commonality possible. Therefore, it is possible to add a motor stop function without having to provide a dedicated terminal for stopping the motor.In particular, when converting the circuit to an IC, it is not only possible to reduce the cost by reducing the number of terminals, but also to reduce the cost by reducing the number of terminals. By providing multiple functions, the terminals can be used effectively, and high layer efficiency and high added value can be achieved.

Note that the speed detection signal is necessary for motor speed control.
It has no particular meaning when stopping the motor. Therefore, there is no problem in the system even if the output terminal of the speed detector and the stop command signal input terminal are made common, and the stop command signal is forcibly inputted from the outside to the common terminal to stop the motor.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram of a motor stopping device according to an embodiment of the present invention, and FIG. 2 is a circuit diagram of a conventional motor stopping device. 1 to 3... Drive coil, 10... Motor drive means, 30... Speed detector, 40...
...Stop command detection circuit.

Claims (1)

[Claims] a motor drive coil of multiple phases; a motor drive means that sequentially energizes the drive coil to apply a drive torque to the motor; a motor speed detector whose output signal range is constrained within a predetermined level; a stop command detection circuit that detects that a signal exceeding the output signal range of the speed detector is input as a stop command signal to the output of the speed detector; and an output of the stop command detection circuit that drives the motor of the motor drive means. A motor stop device configured to stop torque supply.