JP2001136768A - Control device for motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a driving gear for a motor, capable of reducing the number of connection wires connecting a drive part and a control part, in the driving gear for the motor provided with the drive part having a rotation sensor for the motor and its temperature sensor and the control part for controlling the motor in this drive part. SOLUTION: This driving gear for a motor is provided with a drive part 1 having a motor 3, a magnetic pole sensor 4 detecting a rotational speed of the motor 3 to generate a rotational speed signal A, and temperature sensors 6, 8 to 10, 14 detecting a temperature of the motor 3 to generate a temperature signal C, and a control part 2 drive controlling the motor 3, based on the rotational speed signal A and the temperature signal C, The drive part 1, having compound signal generation parts 5, 7, 11 to 13, 15 to 17 generating the rotational speed signal A and the temperature signal C into a single compound signal E, transmits this compound signal E to the control part 2 via a single cable K4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a motor driving device, and more particularly, to a driving unit having a rotation sensor for detecting the number of rotations of a motor and a temperature sensor for detecting the temperature of the motor, and a motor for the driving unit. And a control unit for controlling the motor.

[0002]

2. Description of the Related Art In an electric nursing bed apparatus, a back is raised, a knee is raised, etc., by operating a switch.

[0003] Such an apparatus includes a drive section 51 as shown in FIG. 5 and a control section 52 for controlling the drive section 51. The driving unit 51 includes a motor 53, a magnetic pole sensor 5
4, a thermistor (temperature sensor) 55, a control power input terminal T11, a pair of motor power input terminals T12 and T13, a magnetic pole sensor output terminal T14, a thermistor connection terminal T15,
And a ground terminal T16.

[0004] A pair of power input terminals (brushes) of the motor 53 are connected to a pair of motor power input terminals T12 and T13. A magnetic pole sensor 54 is provided near the sensor magnet fixed to the rotor of the motor 53. The power supply terminal of the magnetic pole sensor 54 is connected to the control power supply input terminal T11 and the ground terminal T16, and its output terminal is connected to the magnetic pole sensor output terminal T14. The magnetic pole sensor 54 generates and outputs a rotation speed signal (pulse signal) P according to a change in a magnetic field when the sensor magnet rotates.

[0005] A thermistor 55 is disposed near the heat generating portion of the motor 53. The thermistor 55 has one terminal connected to the thermistor connection terminal T15 and the other terminal connected to the ground terminal T1.
6 is connected. The thermistor 55 has a resistance value that decreases as the temperature of the motor 53 increases.

The control section 52 includes a motor power supply circuit 56, an arithmetic circuit 57, a switch 58, a constant voltage power supply circuit 59, a comparator 60, a resistor 61, a reference power supply Vref, and a control power supply output terminal T.
17, a pair of motor power output terminals T18 and T19, a magnetic pole sensor input terminal T20, a thermistor connection terminal T21, and a ground terminal T22.

[0007] Motor energizing circuit 56 and constant voltage power supply circuit 5
9 are connected to an external power supply V. The constant voltage power supply output terminal of the constant voltage power supply circuit 59 is connected to the arithmetic circuit 57 and the comparator 60. The constant voltage power supply output terminal of the constant voltage power supply circuit 59 is connected to the control power supply output terminal T17 and to the thermistor connection terminal T21 via the resistor 61.

A node N11 between the resistor 61 and the thermistor connection terminal T21 is connected to a non-inverting input terminal of the comparator 60. A reference voltage V is applied to an inverting input terminal of the comparator 60.
ref is connected. Output terminal of comparator 60, switch 5
8 and the magnetic pole sensor input terminal T20 are connected to the arithmetic circuit 57.

The arithmetic circuit 57 is connected to a motor energizing circuit 56, and the motor energizing circuit 56 is connected to a pair of motor power output terminals T18 and T19. The ground terminal T22 is grounded.

The drive unit 51 and the control unit 52 are connected by six cables K11 to K16. More specifically, the control power output terminal T17 and the control power input terminal T11 are connected by a control power cable K11. A pair of motor power output terminals T18 and T19 and a motor power input terminal T1
2 and T13 are connected by power supply cables K12 and K13.

The magnetic pole sensor input terminal T20 and the magnetic pole sensor output terminal T14 are connected by a rotation sensor cable K14. The thermistor connection terminal T21 and the thermistor connection terminal T15 are connected by a temperature sensor cable K15. The ground terminal T22 and the ground terminal T16 are connected by a ground cable K16.

In this device, when the switch 58 is manually operated, an operation signal S11 based on the operation is input to the arithmetic circuit 57, and a control signal S12 corresponding to the operation signal S11 is output from the arithmetic circuit 57 to the motor energizing circuit. It is output to 56. Then, based on the control signal S12, the drive current is supplied from the motor energizing circuit 56 to the motor 53 by the power supply cable K1.
2, K13. Then, when the motor 53 is driven to rotate, the magnetic pole sensor 54 generates a rotation speed signal (pulse signal) P corresponding to the rotation angle (rotation speed) of the rotor,
The signal is output to the arithmetic circuit 57 via the rotation sensor cable K14. Then, the feedback control signal S13 based on the rotation speed signal P is output from the arithmetic circuit 57 to the motor energizing circuit 56. Thereby, the rotation speed of the motor 53 is feedback-controlled.

When the temperature of the motor 53 rises, the potential of the node N11 is a potential obtained by dividing the constant voltage Vcc generated by the constant voltage power supply circuit 59 by the resistor 61 and the thermistor 55. Falling down like value. Then, the temperature of the motor 53 rises and the node N11
Is lower than the reference power supply Vref, the comparator 60 outputs an L-level comparison signal S14.

When the L-level comparison signal S14 is continuously input to the arithmetic circuit 57 for a predetermined period of time, it is determined that the motor 53 is in an abnormally heated state, and the L-level energization permission / non-permission signal (energization cutoff signal). S15 is output to the motor energization circuit 56. Then, the supply of the drive current from the motor energizing circuit 56 to the motor 53 is stopped. Therefore, when the motor 53 generates heat abnormally, such as when the rotation of the motor 53 is suppressed (locked) by an abnormal load, further generation of heat is prevented.

Thereafter, when the temperature of the motor 53 decreases and the potential of the node N11 becomes higher than the reference power supply Vref, the comparator 60 outputs the H-level comparison signal S14. When an H-level comparison signal is input to the arithmetic circuit 57, it is determined that the temperature of the motor 53 is normal, and an H-level energization permission / non-permission signal (energization permission signal) S15 is sent to the motor energization circuit 56. Is output. Then, the motor energizing circuit 56 can supply a driving current to the motor 53.

[0016]

By the way, in the electric nursing care bed apparatus and the like, the position of the control unit 52 and the position of the drive unit 51 are far from each other due to its structure. And in the above-mentioned device, in order to connect the drive part 51 and the control part 52,
Since six cables K11 to K16 are required, there is a problem that the cost of the cables K11 to K16 increases. Also, the cables K11 to K16 required by the device
Weight becomes heavy.

An object of the present invention is to provide a motor driving apparatus including a driving unit having a motor rotation sensor and a motor temperature sensor, and a control unit for controlling the motor of the driving unit. It is an object of the present invention to provide a motor drive device capable of reducing the number of connections for connecting the motors.

[0018]

SUMMARY OF THE INVENTION In order to solve the above problems, an invention according to claim 1 includes a motor, a rotation sensor for detecting a rotation speed of the motor and generating a rotation speed signal, and
A motor drive device comprising: a drive unit having a temperature sensor that detects a temperature of the motor and generates a temperature signal; and a control unit that drives and controls the motor based on the rotation speed signal and the temperature signal. The driving unit includes a composite signal generation unit that converts the rotation speed signal and the temperature signal into one composite signal, and transmits the composite signal to the control unit via one connection. I do.

According to a second aspect of the present invention, in the motor driving apparatus according to the first aspect, the temperature signal is a signal whose potential changes according to the temperature of the motor, and the rotation speed signal is A signal whose level is inverted in accordance with the rotation angle of the motor, wherein the composite signal generation unit generates a one-shot pulse signal based on a rise or fall of the rotation speed signal; An OR circuit having a pulse signal and the temperature signal as input signals is provided, and the composite signal is a signal based on an output signal of the OR circuit.

According to a third aspect of the present invention, in the driving apparatus for a motor according to the second aspect, the composite signal generating section includes:
An essential point is to provide an operational amplifier that amplifies an output signal of the OR circuit and outputs the amplified signal as the composite signal.

The invention described in claim 4 is the first to third aspects of the present invention.
In the motor driving device according to any one of the above, the control unit includes a separation circuit unit that separates the composite signal into a signal based on the rotation speed signal and a signal based on the temperature signal. And

The invention according to claim 5 is the invention according to claims 1 to 4
5. The motor driving device according to claim 1, wherein the rotation sensor is provided near a sensor magnet fixed to a rotor of the motor, and the level is inverted according to a change in a magnetic field when the sensor magnet rotates. The temperature sensor comprises a thermistor having a resistance value that changes in accordance with a change in the temperature of the motor, and a resistor having a constant resistance value. The point is that the divided voltage is divided into a temperature signal.

According to the first aspect of the present invention, the rotational speed signal and the temperature signal are combined into a single composite signal by the composite signal generating section of the driving section, and transmitted to the control section via a single connection. . Therefore, the number of connections for connecting the drive unit and the control unit is reduced.

According to the second aspect of the present invention, when a rotation speed signal whose level is inverted according to the rotation angle of the motor rises or falls, a one-shot pulse signal is generated by the multivibrator and input to the OR circuit. Is done. Therefore,
Even if the motor stops when the rotation speed signal is at the H level, the signal input to the OR circuit when the motor stops is at the L level. This allows the output signal of the OR circuit when the motor stops to
Regardless of the rotation angle of the motor, the signal can be a signal corresponding to the temperature signal.

According to the third aspect of the present invention, since the output signal of the OR circuit is amplified by the operational amplifier and output as the composite signal, the voltage level of the signal is hardly reduced, and the control unit has high accuracy. Can be transmitted.

According to the fourth aspect of the invention, the composite signal is separated into a signal based on the rotation speed signal and a signal based on the temperature signal by the separation circuit of the control unit. Accordingly, the drive of the motor is controlled based on the separated signals.

According to the fifth aspect of the present invention, when the rotor rotates, a change in the magnetic field generated by the sensor magnet rotating with the rotor is detected by the magnetic pole sensor, and the level is inverted according to the change in the magnetic field. Is generated. When the temperature of the motor changes, the resistance of the thermistor changes. A predetermined voltage is divided by the thermistor and the resistance, and the divided voltage is used as a temperature signal.

[0028]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS. FIG. 1 shows a motor driving device. The motor driving device includes a driving unit 1,
And a control unit 2 for controlling the driving unit 1.

The driving section 1 includes a motor 3, a magnetic pole sensor 4 as a rotation sensor, a monostable multivibrator (hereinafter simply referred to as a multivibrator) 5, a thermistor 6, resistors 7 to 13, operational amplifiers 14 and 15, diodes 16 and 1.
7, control power input terminal T1, a pair of motor power input terminals T2, T3, composite signal output terminal T4, and ground terminal T5
Is provided. In this embodiment, the thermistor 6, the resistors 8 to 10, and the operational amplifier 14 constitute a temperature sensor. Further, in the present embodiment, the multivibrator 5, the resistors 7, 11 to 13, the diodes 16, 17 and the operational amplifier 15 constitute a composite signal generation unit.

A pair of power input terminals (brush) of the motor 3
Are connected to a pair of motor power input terminals T2 and T3. A magnetic pole sensor 4 is provided near the sensor magnet fixed to the rotor of the motor 3. The power supply terminals of the magnetic pole sensor 4 include a control power supply input terminal T1 and a ground terminal T5.
And its output terminal is connected to the multivibrator 5. The magnetic pole sensor 4 generates a rotation speed signal (pulse signal) A according to a rotor rotation angle (rotation speed) according to a change in a magnetic field when the sensor magnet rotates together with the rotor.
And outputs the signal A to the multivibrator 5 (see FIG. 2).

The power terminal of the multivibrator 5 is connected to the control power input terminal T1 and the ground terminal T5, and its output terminal is connected to the control power input terminal T1 via the resistor 7 and to the anode of the diode 16. Have been. The multivibrator 5 outputs a one-shot pulse signal B, which becomes H level for a predetermined time according to the rise of the rotation speed signal A, to the diode 16 (see FIG. 2).

A thermistor 6 is located near the heat generating portion of the motor 3.
Is arranged. The thermistor 6 has one terminal connected to the control power supply input terminal T1 via the resistor 8, and the other terminal connected to the ground terminal T5. This thermistor 6 is a motor 3
When the temperature rises, the resistance value decreases.

The node N1 between the thermistor 6 and the resistor 8 is
The resistor 9 is connected to an inverting input terminal of the operational amplifier 14. The output terminal of the operational amplifier 14 is connected to its own inverting input terminal via the resistor 10. The non-inverting input terminal of the operational amplifier 14 is connected to the ground terminal T5. That is, the operational amplifier 14 is subjected to negative feedback, and the operational amplifier 14 and the resistors 9 and 10 constitute a first inverting amplifier. The output terminal of the operational amplifier 14 is
It is connected to the anode of the diode 17.

The cathodes of the diodes 16 and 17 are connected, and the node N2 is connected to the ground terminal T5 via the resistor 11. That is, the diode 1
An OR circuit in which both anodes serve as input terminals and the node N2 serves as an output terminal is constituted by 6, 17 and the resistors 7, 11.

The node N2 is connected to the inverting input terminal of the operational amplifier 15 via the resistor 12. Operational amplifier 1
The output terminal 5 is connected to its own inverting input terminal via a resistor 13. The non-inverting input terminal of the operational amplifier 15 is connected to the ground terminal T5. That is, the operational amplifier 1
5 is a negative feedback, the operational amplifier 15 and the resistor 1
2 and 13 constitute a second inverting amplifier. The output terminal of the operational amplifier 15 is a composite signal output terminal T4
It is connected to the.

The control unit 2 includes a motor energizing circuit 21, an arithmetic circuit 22, a switch 23, a constant voltage power supply circuit 24, a comparator 2
5, inverting buffer 26, buffer 27, on / off switches 28 and 29, capacitors 30 and 31, operational amplifier 3
2, 33, a reference power supply Vref1 to Vref3, a control power output terminal T6, a pair of motor power output terminals T7 and T8, a composite signal input terminal T9, and a ground terminal T10. In the present embodiment, the arithmetic circuit 22, the comparator 25, the inversion buffer 26, the buffer 27, the on / off switches 28 and 29,
The capacitors 30, 31, the operational amplifiers 32, 33, and the reference power supplies Vref1 to Vref3 constitute a separation circuit unit.

Motor energizing circuit 21 and constant voltage power supply circuit 2
4 are connected to an external power supply V. This constant voltage power supply circuit 59 generates a constant voltage Vcc. The constant voltage power supply output terminal of the constant voltage power supply circuit 24 includes a power supply input terminal of the arithmetic circuit 22, a comparator 25, an inversion buffer 26, a buffer 27, operational amplifiers 32 and 33, and a control power supply output terminal T.
6 is connected.

The composite signal input terminal T9 is connected to the inverting input terminal of the comparator 25. A reference voltage Vref1 is connected to a non-inverting input terminal of the comparator 25. The output terminal of the comparator 25 is connected to the arithmetic circuit 22. The output terminal of the comparator 25 is connected to a control signal input terminal of an on / off switch 28 via an inversion buffer 26. The on / off switch 28 is connected to the inversion buffer 2
6 is turned on when the control signal G output from 6 is at the H level,
Turns off when L level.

The composite signal input terminal T9 is connected to a non-inverting input terminal of the operational amplifier 32 via an on / off switch 28. The node N3 between the on / off switch 28 and the non-inverting input terminal of the operational amplifier 32 is grounded via the capacitor 30.

The output terminal of the operational amplifier 32 is connected to its own inverting input terminal. The output terminal of the operational amplifier 32 is connected to a non-inverting input terminal of the operational amplifier 33 via an on / off switch 29. The node N between the on / off switch 29 and the non-inverting input terminal of the operational amplifier 33
4 is grounded via a capacitor 31. The arithmetic circuit 22 is connected to an on / off switch 2 via a buffer 27.
9 connected to the control signal input terminal of the
9 turns on when the control signal I output from the arithmetic circuit 22 and input via the buffer 27 is at the H level, and turns off when the control signal I is at the L level.

The output terminal of the operational amplifier 33 is connected to its own inverting input terminal. The output terminal of the operational amplifier 33 is connected to the arithmetic circuit 22. This arithmetic circuit 2
2 is connected to reference voltages Vref2 and Vref3 and a switch 23.

The arithmetic circuit 22 is connected to the motor energizing circuit 21 and operates the operation signal S1 output from the switch 23, the comparison signal F output from the comparator 25, and the operational amplifier 3.
S2, S3, K based on the output signal J
Is output to the motor energizing circuit 21.

More specifically, the arithmetic circuit 22 includes a switch 2
A control signal S2 for energizing the motor 3 is output to the motor energizing circuit 21 in accordance with the operation signal S1 output from the motor 3.
Further, the arithmetic circuit 22 outputs a feedback control signal S3 for controlling a drive current value supplied to the motor 3 to the motor energizing circuit 21 in accordance with the comparison signal F output from the comparator 25.

The arithmetic circuit 22 has a comparator (not shown), and the potential of the output signal J of the operational amplifier 33 is equal to the reference voltage V.
If it is lower than ref2, it is determined that the motor 3 is in an abnormal heat generation state, and an L level energization permission / non-permission signal (energization cutoff command signal) K is output to the motor energization circuit 21. afterwards,
When the potential of the output signal J of the operational amplifier 33 becomes higher than the reference voltage Vref3, the arithmetic circuit 22 determines that the temperature of the motor 3 is normal, and outputs an H level energization enable / disable signal (energization enable signal) K to the motor. Output to the energizing circuit 21. still,
The reference voltage Vref2 is set lower than the reference voltage Vref3 (see FIG. 3).

The motor energizing circuit 21 is connected to a pair of motor power output terminals T7 and T8, and receives the motor 3 based on a control signal S2, a feedback control signal S3, and an energization enable / disable signal K input from the arithmetic circuit 22. To supply the drive current.

The ground terminal T10 is grounded. The drive unit 1 and the control unit 2 are connected by five cables K1 to K5. Specifically, the control power output terminal T6 and the control power input terminal T1 are connected by a control power cable K1.
A pair of motor power output terminals T7, T8 and motor power input terminals T2, T3 are connected by power supply cables K2, K3.

The composite signal input terminal T9 and the composite signal output terminal T4 are connected by a composite signal cable K4.
The ground terminal T10 and the ground terminal T5 are connected to a ground cable K5.
Connected.

The thermistor 6, the resistors 8 to 10, and the operational amplifier 14 adjust the voltage of the temperature signal C output from the operational amplifier 14 when the temperature of the motor 3 rises abnormally to the H level of the one-shot pulse signal B. It is set to be lower than the voltage at the time.

Next, the operation of the motor driving device constructed as described above will be described with reference to FIGS. “Operation in Normal Time when Motor 3 is at Low Temperature (at Time t1 in FIGS. 2 and 3)” Now, switch 23 is manually operated, and operation signal S1 based on the operation is input to arithmetic circuit 22,
A control signal S2 corresponding to the operation signal S1 from the arithmetic circuit 22
Is output to the motor energizing circuit 21. Then, a drive current based on the control signal S2 is supplied from the motor energizing circuit 21 to the motor 3 via the power supply cables K2 and K3. Then, when the motor 3 is driven to rotate, a rotation speed signal (pulse signal) A corresponding to the rotation angle (rotation speed) of the rotor is generated by the magnetic pole sensor (rotation sensor), and the signal A is transmitted to the multivibrator 5. Is entered. Then, the one-shot pulse signal B is output from the multivibrator 5 according to the rise of the rotation speed signal A.

On the other hand, the temperature signal C, which is the output signal of the operational amplifier 14, that is, the potential of the node N1 obtained by dividing the constant voltage Vcc by the resistor 8 and the thermistor 6 is inverted and current-amplified by the first inverting amplifier. The signal is normal motor 3
Is low and the potential of the thermistor 6 is high, so that the potential becomes low.

The one-shot pulse signal B and the temperature signal C
Are input to the anodes of the diodes 16 and 17, respectively, that is, input to the OR circuit, and the OR output signal D is output to the second inverting amplifier. Then, the OR output signal D
Are inverted by the second inverting amplifier and current-amplified, and output as a composite signal E to the comparator 25 and the on / off switch 28 of the control unit 2 via the composite signal cable K4. The composite signal E is a one-shot pulse signal B
Is a signal whose potential is lower than the reference voltage Vref1 only when is output.

As a result, the comparison signal F output from the comparator 25 goes high in synchronization only when the one-shot pulse signal B is output. The comparison signal F as the extracted signal is output to the arithmetic circuit 22 and inverted via the inverting buffer 26 to become the control signal G, which is output to the control signal input terminal of the on / off switch 28.

Therefore, the on / off switch 28 is turned off only when the one-shot pulse signal B is output.
As a result, the signal at the node N3 has its falling edge based on the one-shot pulse signal B removed from the composite signal E,
The inverted phase temperature signal H has a substantially opposite phase to the temperature signal C, and has a high potential.

On the other hand, a control signal I is input to the on / off switch 29 from the arithmetic circuit 22 via the buffer 27. The control signal I is different from the control signal G in that the H level period (ON period) is the L level period (OFF period).
Is set to be short.

Therefore, the output signal J output from the operational amplifier 33 is substantially the same as the negative-phase temperature signal H, and the control signal I is H
When the signal is at the level, the signal is sampled and held, and has a high potential.

Then, the arithmetic circuit 22 determines that the potential of the output signal J is higher than the reference voltage Vref3 and that the temperature of the motor 3 is normal.
1 is an H level energization permission / non-permission signal (energization permission signal)
K is output.

The arithmetic circuit 22 detects the number of rotations of the rotor (rotation angle) based on the comparison signal F output from the comparator 25.
, A feedback control signal S3 corresponding to the rotor speed is output.

Then, the control signal S2, the energization permission signal K,
A drive current is supplied to the motor 3 from the motor energizing circuit 21 based on the feedback control signal S3. More specifically, based on the control signal S2 and the energization permission signal K,
A drive current is supplied from the motor energizing circuit 21 to the motor 3. Further, based on the feedback control signal S3, the drive current amount is controlled, and the rotation speed of the motor 3 is feedback-controlled. "Operation when motor 3 generates abnormal heat (at time t2 in FIGS. 2 and 3)" When the temperature of motor 3 rises, the resistance value of thermistor 6 decreases and is the output signal of operational amplifier 14. The potential of the temperature signal C increases.

Then, when the one-shot pulse signal B is not output, the potential of the OR output signal D becomes the temperature signal C
Rises with an increase in the potential of. Therefore, when the one-shot pulse signal B is not output, the potential of the composite signal E falls according to the rise of the temperature signal C.

Then, the potential of the negative-phase temperature signal H falls as the temperature signal C rises. Then, the operational amplifier 33
Output signal J falls stepwise in response to the fall of the negative-phase temperature signal H.

When the potential of the output signal J becomes lower than the reference voltage Vref2 (at timing t11 in FIG. 3), the arithmetic circuit 22 determines that the motor 3 is in an abnormal heat generation state. L for the energizing circuit 21
Level energization permission / non-permission signal (energization cutoff command signal) K
Is output.

Then, the supply of the drive current from the motor energizing circuit 21 to the motor 3 is stopped based on the energization cutoff command signal K regardless of the control signal S2. Therefore, the motor 3
The further generation of heat is prevented. “Operation when the motor 3 returns to the normal state (at time t3 in FIGS. 2 and 3)” When the supply of the driving current to the motor 3 is stopped and the temperature of the motor 3 falls, the resistance value of the thermistor 6 Rises, and the potential of the temperature signal C, which is the output signal of the operational amplifier 14, drops.

Then, the potential of the OR output signal D falls as the potential of the temperature signal C falls. Therefore, the potential of the composite signal E rises as the temperature signal C falls. Then, the potential of the negative-phase temperature signal H rises according to the fall of the temperature signal C.

Then, the potential of the output signal J output from the operational amplifier 33 rises stepwise in accordance with the rise of the negative-phase temperature signal H. Then, in the arithmetic circuit 22, the output signal J
Is higher than the reference voltage Vref3 (at the timing t12 in FIG. 3), it is determined that the temperature of the motor 3 is normal, and the arithmetic circuit 22 sends the H signal to the motor energizing circuit 21.
A level energization permission / non-permission signal (energization permission signal) K is output.

Then, the control signal S2 and the energization permission signal K
, A driving current is supplied from the motor energizing circuit 21 to the motor 3 again. Also, the feedback control signal S3
, The driving current amount is controlled, and the rotation speed of the motor 3 is feedback-controlled.

Next, the characteristic effects of the above embodiment will be described below. (1) The rotational speed signal A and the temperature signal C are converted into one composite signal E by the multivibrator 5, the resistors 7, 11 to 13, the diodes 16, 17 and the operational amplifier 15, and one composite signal cable is transmitted to the control unit 2. Output via K4.
The composite signal E is supplied to an arithmetic circuit 22, a comparator 25, an inverting buffer 26, a buffer 27, and on / off switches 28 and 2.
9, a signal F based on the rotation speed signal A and a signal J based on the temperature signal C are separated by the capacitors 30 and 31, the operational amplifiers 32 and 33, and the reference power supplies Vref1 to Vref3. Then, the motor energizing circuit 21 is controlled based on the signals F and J, and a driving current is supplied to the motor 3. Therefore, the number of connections (cables) connecting the drive unit 1 and the control unit 2 is reduced. As a result, the cost of the cables K1 to K5 is reduced. Also, the cables K1 to K required by the device
5, the weight of the device is reduced, and the weight of the device is reduced.

(2) When the rotation speed signal A whose level is inverted according to the rotation angle of the motor 3 rises, the multivibrator 5 generates a one-shot pulse signal B and inputs it to the OR circuit. Therefore, even if the motor 3 stops when the rotation speed signal A is at the H level, the signal input to the OR circuit when the motor 3 stops is at the L level. As a result, the motor 3
The OR output signal D of the OR circuit at the time of stoppage can be a signal corresponding to the temperature signal C regardless of the rotation angle of the motor 3. As a result, even if the motor 3 stops when the rotation speed signal A is at the H level, the temperature information is transmitted to the control unit 2.

(3) The OR output signal D of the OR circuit is
Since the current is amplified by the inverting amplifier (the operational amplifier 15) and output to the control unit 2 as the composite signal E, the voltage level of the signal does not easily decrease. As a result, for example, a reduction in the voltage level of the signal due to external noise or wiring resistance is reduced, and the composite signal E is transmitted to the control unit 2 with high accuracy.
As a result, malfunctions are reduced.

(4) The reference voltage Vref2 is equal to the reference voltage Vref3.
When the voltage is set lower and the potential of the signal J based on the temperature signal C becomes lower than the reference voltage Vref2, the motor energizing circuit 21 is unable to supply the drive current to the motor 3, and thereafter, the potential of the signal J becomes higher than the reference voltage Vref3. When it becomes higher, the motor energizing circuit 21 can supply a drive current to the motor 3. As a result, when the motor 3 enters an abnormal heat generation state, the motor 3
Is stopped until its temperature is low enough.

The above embodiment may be modified as follows. The driving unit 1 according to the above embodiment includes a driving unit 41 shown in FIG.
May be changed to The configuration of the driving unit 41 will be described by describing different points from the driving unit 1. The output terminal of the multivibrator 5 is connected to the composite signal output terminal T4. A node N between the thermistor 6 and the resistor 8
1 is connected to the composite signal output terminal T4. That is,
By connecting the node N1 to the output terminal of the multivibrator 5, a wired OR circuit is formed in which the node N1 and the output terminal of the multivibrator 5 are input terminals, and a connection point (node) N5 is an output terminal. .
In this case, the thermistor 6 and the resistor 8 constitute a temperature sensor, and the multivibrator 5 constitutes a composite signal generator. The thermistor 6 and the resistor 8 are set such that the voltage at the node N1 when the temperature of the motor 3 is low is lower than the voltage when the one-shot pulse signal B is at the H level.

Thus, the rotation speed signal A generated by the magnetic pole sensor 4 and the temperature signal L generated at the node N1 are
The signal is combined into one composite signal M by the wired OR circuit, and is output to the control unit via one composite signal cable K4. Therefore, the number of connections (cables) connecting the drive unit 1 and the control unit is reduced. In addition, in this case, the operational amplifiers 14 and 15 having low heat resistance become unnecessary, and the number of elements constituting the driving unit 41 is reduced as compared with the above embodiment.

In this case, since the composite signal M has a different waveform from the composite signal E of the above embodiment, the control unit 2
Needs to be changed so that the composite signal M can be separated into a signal based on the rotation speed signal A and a signal based on the temperature signal L.

In the above embodiment, the control unit 2 is provided with the separation circuit unit for separating the composite signal E into a signal based on the rotation speed signal A and a signal J based on the temperature signal C. You may. In this case, for example, if the state where the potential of the composite signal E is equal to or lower than a predetermined value (for example, the reference voltage Vref2) continues for a predetermined time (a period longer than the H level period of the one-shot pulse signal B), the motor 3 is in an abnormally heated state It is determined that there is, and the supply of the drive current to the motor 3 is stopped. Further, a pulse in which the potential of the composite signal E is lower than a predetermined value (for example, the reference voltage Vref1) is detected to detect the number of revolutions. As described above, even if the composite signal E is not separated, the same effect as in the above embodiment can be obtained.

In the above-described embodiment, the magnetic pole sensor 4 is provided as a rotation sensor. However, the rotation sensor may be changed to another rotation sensor as long as the rotation signal A can be generated according to the rotor rotation angle (rotation speed). For example, a disk having a radial slit formed on the rotor rotation shaft may be fixed, and a photo interrupter may be provided instead of the magnetic pole sensor 4 to generate a rotation speed signal according to the rotor rotation angle (rotation speed). . Even in this case, the same effect as in the above embodiment can be obtained.

In the above-described embodiment, the thermistor 6 is used as the temperature sensor. However, the temperature sensor may be changed to another temperature sensor as long as the temperature signals C and L whose potential changes according to the temperature of the motor 3 can be generated. . Even in this case, the same effect as in the above embodiment can be obtained.

The technical ideas other than the claims that can be understood from the above embodiments will be described below together with their effects. (A) a driving unit including a motor, a rotation sensor for detecting a rotation speed of the motor and generating a rotation speed signal, and a temperature sensor for detecting a temperature of the motor and generating a temperature signal; A drive unit, comprising: a composite signal generation unit that converts a signal and the temperature detection signal into one composite signal, and outputs the composite signal via one connection.

In this manner, the rotational speed signal and the temperature signal are combined into a single composite signal by the composite signal generation section of the drive section, and are output via a single connection. Therefore, the number of necessary connections is reduced.

(B) A separation circuit for separating a composite signal input from the outside via one connection into a signal based on a rotation speed signal and a signal based on a temperature signal is provided. And a control unit for controlling driving of an external motor based on the temperature signal.

In this manner, the composite signal input from the outside via one connection is separated into a signal based on the rotation speed signal and a signal based on the temperature signal by the separating circuit section, and the separated signals are respectively separated. The drive of the motor is controlled based on the signal. Therefore, the number of necessary connections is reduced.

(C) In the motor driving device according to claim 4, the separation circuit section converts the composite signal into the first signal.
A signal synchronized with the shot pulse signal is extracted, and the extracted signal is converted into a signal based on the rotation speed signal, and a component of the one-shot pulse signal is removed from the composite signal based on the extracted signal to generate the rotation speed signal. A motor drive device, characterized in that the signal is based on the following.

In this way, a signal synchronized with the one-shot pulse signal is extracted from the composite signal by the separation circuit, and the extracted signal is converted into a signal based on the rotation speed signal, and based on the extracted signal. The component of the one-shot pulse signal is removed from the composite signal to obtain a signal based on the rotation speed signal. Thus, the composite signal is separated.

[0082]

As described in detail above, according to the present invention,
In a motor drive device including a drive unit having a motor rotation sensor and a motor temperature sensor, and a control unit that controls the motor of the drive unit, the number of connections connecting the drive unit and the control unit is reduced. It is possible to provide a motor driving device that can be driven.

[Brief description of the drawings]

FIG. 1 is an electrical configuration diagram of a motor driving device according to an embodiment.

FIG. 2 is a waveform chart of a driving unit according to the embodiment.

FIG. 3 is a waveform chart in the control unit according to the embodiment.

FIG. 4 is an electrical configuration diagram of another example of a driving unit.

FIG. 5 is an electrical configuration diagram of a conventional motor driving device.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 drive unit 2 control unit 3 motor 4 magnetic pole sensor 5 monostable multivibrator 6 thermistor
7, 8, 11 to 13 ... resistor, 15, 32, 33 ... operational amplifier, 16, 17 ... diode, 22 ... arithmetic circuit, 25
... Comparator, 26 ... Reversal buffer, 27 ... Buffer, 2
8, 29: On / off switch, 30, 31, Capacitor, Vref1 to Vref3: Reference voltage, K1 to K5: Cable.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masahiro Takeda 390 Umeda, Kosai-shi, Shizuoka Asmo Co., Ltd. F-term (reference) 5H550 AA20 BB06 BB08 DD01 FF05 GG03 HA01 HA04 JJ02 LL06 LL39 MM06 5H571 AA20 BB05 BB07 FF06 GG06 HA HA04 HA16 JJ02 JJ06 LL06 LL36 MM06

Claims (5)

[Claims] A driving unit having a motor, a rotation sensor for detecting a rotation speed of the motor and generating a rotation speed signal, and a temperature sensor for detecting a temperature of the motor and generating a temperature signal; A motor driving device comprising: a control unit that controls the driving of the motor based on a rotation speed signal and the temperature signal; wherein the driving unit is configured to convert the rotation speed signal and the temperature signal into one composite signal. A control device for a motor, comprising: a signal generator; and transmitting the composite signal to the controller via a single connection. 2. The motor driving device according to claim 1, wherein the temperature signal is a signal whose potential changes in accordance with the temperature of the motor, and the rotation speed signal is in accordance with the rotation angle of the motor. The composite signal generation unit generates a one-shot pulse signal based on the rise or fall of the rotation speed signal; the one-shot pulse signal; and the temperature signal. And an OR circuit that receives the OR signal as an input signal, and wherein the composite signal is a signal based on an output signal of the OR circuit. 3. The motor driving device according to claim 2, wherein the composite signal generation unit includes an operational amplifier that amplifies an output signal of the OR circuit and outputs the amplified output signal as the composite signal. Drive circuit. 4. The motor driving device according to claim 1, wherein the control unit converts the composite signal into a signal based on the rotation speed signal and a signal based on the temperature signal. A motor driving device comprising a separation circuit unit for separating. 5. The motor driving device according to claim 1, wherein the rotation sensor is provided near a sensor magnet fixed to a rotor of the motor, and when the sensor magnet rotates. A magnetic pole sensor that generates a rotation speed signal whose level is inverted according to a change in the magnetic field of the motor. The temperature sensor includes a thermistor whose resistance changes according to a change in the temperature of the motor, and a resistor having a constant resistance. And a voltage divider that divides a predetermined voltage by the thermistor and the resistor and uses the divided voltage as a temperature signal.