JP3172610B2 - Motor control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a motor control device.

[0002]

2. Description of the Related Art Conventionally, a voltage from a power supply is controlled by a transistor to adjust a value of a voltage applied to a motor coil, which will be described with reference to FIGS.

In FIGS. 3 and 4, reference numeral 1 denotes a rotor formed by a permanent magnet, 2 denotes a fixed armature for applying a magnetic field generated by a current flowing through a motor coil 3 to the rotor 1, and 4 denotes a rotor. 1 is a Hall element that magnetically detects the rotational position of 1 and outputs, for example, + (plus) for N poles and − (minus) for S poles, 5 is a power supply for driving the motor, and 6 is A signal transmission unit 7 for transmitting a control signal for changing the number of rotations of the motor is a circuit ground.

[0004] Q1 and Q2 are NPN type transistors,
Q3 and Q4 are PNP-type transistors and constitute a bridge circuit. Q5 is an NPN transistor that varies the internal resistance and adjusts the value of the voltage applied to the bridge circuit in response to the control signal input via OP2.

[0005] OP1 is an operational amplifier for amplifying and shaping the output of the Hall element 4, and OP2 is an operational amplifier for driving Q5 and operates as a buffer.

R1 is a resistor for applying a constant voltage to the Hall element 4, and R2 and R3 are resistors for applying an output from the OP1 to the bridge circuit. INV1 is an inverting circuit for inverting the polarity of the input signal.

The voltage from the power supply 5 is applied to the collector of the transistor Q5 and to the Hall element 4 via the resistor R1. At this time, when a control signal is sent from the signal sending unit 6 to rotate the motor, the control signal is input to the base of the transistor Q5 via the operational amplifier OP2, and the transistor Q5 responds to the control signal to cause the collector-emitter to respond. The internal resistance between them is varied. Therefore, the voltage applied to the collector of the transistor Q5 is output after being adjusted by the internal resistance between the collector and the emitter.

On the other hand, the Hall element 4 always detects the rotational position of the rotor 1, and outputs + when it is the N pole and − when it is the S pole. Then, after the waveform is shaped by the operational amplifier OP1, the voltage is applied to the bases of the transistors Q1 and Q3 via the resistor R2, the polarity is inverted by the inverting circuit INV1, and then the transistors Q2 and Q4 are connected via the resistor R3.
Applied to the base.

At this time, the Hall element 4 detects the N pole,
When the + output is sent, a + voltage is applied to the bases of the transistors Q1 and Q3, and a-voltage is applied to the bases of the transistors Q2 and Q4. Accordingly, the collector and emitter of the transistors Q1 and Q4 are turned ON, and the voltage from the transistor Q5 is applied to the transistor Q1, the motor coil 3, and the transistor Q4.

When the Hall element 4 detects the S pole and a negative output is sent, a negative voltage is applied to the bases of the transistors Q1 and Q3 and a positive voltage is applied to the bases of the transistors Q2 and Q4. As a result, the collector and emitter of the transistors Q2 and Q3 are turned on, and the voltage from the transistor Q5 is changed to the transistor Q2, the motor coil 3, and the transistor Q
3 is applied.

Therefore, a signal as shown in FIG.
When output from P1, a voltage as shown in FIG. 5B is applied between the terminals of the motor coil 3 (between a and b). That is, when the Hall element 4 detects the N pole, the current flows from the point a to the point b via the motor coil, and when the S element detects the S pole, the current flows from the point b to the point a. Therefore, since the direction of the current flowing through the motor coil 3 is switched according to the rotational position of the rotor 1, the rotor 1 continuously rotates in the same direction (the direction of arrow A).

As a result, the control signal is
When the signal is as shown in FIG. 5C, the voltage applied between the terminals of the motor coil 3 (between a and b) is a voltage as shown in FIG. That is, the rotation speed of the rotor 1 is adjusted by the control signal.

[0013]

In the above conventional device, a transistor Q5 for controlling the number of rotations of the motor is required in addition to the transistor used in the bridge circuit, so that the number of transistors increases and the saturation voltage of the transistor increases. The resulting power loss was increasing.

[0014] The present invention aims to provide a motor <br/> over motor controller capable of controlling the number of rotation motor by a transistor using a bridge circuit.

[0015]

The present invention achieves the above object.
In order to achieve this, in a motor control device that continuously rotates the rotor in the same direction by switching the current flowing through the motor coil by a bridge circuit formed of transistors in the forward and reverse directions in response to the rotational position of the rotor,
Signal transmission for sending a control signal to change the rotation speed
Means leaving a detecting means for detecting a rotational position of the rotor, the
The signal transmission means based on the detection signal from the detection means
Switching the control signal sent from the
Then, the above control signal is switched by the switched control signal.
While providing control means for controlling the driving of the ridge circuit,
The bridge circuit, based on the control signal,
Change the internal resistance of the transistor and mark the motor coil.
The value of the applied voltage is varied .

[0016]

Therefore, according to the present invention, the rotation is detected by the detecting means.
Detects the rotational position of the trochanter and controls based on the detected signal
Means for controlling the control signal transmitted from the signal transmitting means.
Switching between positive and negative, and the switched control
By controlling the driving of the bridge circuit with signals
The bridge circuit based on the control signal.
Motor coil by varying the internal resistance of the transistor
The value of the voltage applied to the motor to change the number of rotations of the motor
And the voltage applied to the motor coil
The pressure can be a square wave.

[0017]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is an explanatory diagram showing an electric configuration of a motor control device according to one embodiment of the present invention, and FIG. 2 is a waveform diagram showing each operation of the motor control device according to one embodiment of the present invention.
(A) is a control signal, (b) is an operational amplifier OP3
(C) is the output signal of the operational amplifier OP1,
(D) shows the output signal of the selector S1, (e) shows the output signal of the operational amplifier OP4, and (f) shows the inter-terminal voltage applied between the terminals of the motor coil 3 (between a and b). FIG.
In FIG. 7, the same parts as those in FIGS. 3 and 4 are denoted by the same reference numerals.

In FIG. 1, the operational amplifier OP3 and the resistors R4 and R5 constitute an inverting amplifier for inverting the polarity of the control signal from the signal transmitting section 6, and the operational amplifier OP4 and the resistors R6 and R7 control the control signal from the selector S1. This constitutes an inverting amplifier for inverting the polarity of a signal. The selector S1 is constituted by an analog switch, and selects two input signals in response to an output signal from the operational amplifier OP1. Resistance R8,
R9 is for applying a control signal to the bridge circuit, and resistors R10 and R11 are for dividing the voltage from the power supply 5 to generate a reference voltage for inverting the polarity of the control signal.

The control means is constituted by transistors forming a bridge circuit.

The voltage from power supply 5 is applied to transistors Q1 and Q
2 and the Hall element 4 via the resistor R1. At this time, when a control signal as shown in FIG. 2A is transmitted from the signal transmitting unit 6 to rotate the motor, the control signal is input to one input terminal of the selector S1, and the operational amplifier OP3 and the resistor After the polarity is inverted to a signal as shown in FIG. 2B by the inverting amplifier composed of R4 and R5, the signal is input to the other input terminal. On the other hand, the Hall element 4 constantly detects the rotational position of the rotor 1 and outputs + for the N pole and-for the S pole, and the operational amplifier OP1 shapes the waveform to a signal as shown in FIG. After that, it is input to the selector S1.

At this time, the Hall element 4 detects the N pole,
Is output, the selector S1 inputs the control signal input to one input terminal to the bases of the transistors Q1 and Q3 via the resistor R5, and uses the inverting amplifier composed of the operational amplifier OP4 and the resistors R6 and R7. After inverting the polarity to a signal as shown in 2 (e),
The signal is input to the bases of the transistors Q2 and Q4 via the resistor R9. That is, a positive control signal is applied to the bases of the transistors Q1 and Q3.
The control signal of the negative electrode is input to the base of the fourth.
Therefore, the internal resistance between the collector and the emitter of the transistors Q1 and Q4 changes in response to the control signal,
The voltage from the power supply 5 is adjusted by the transistors Q1 and Q4 and applied to the motor coil 3.

[0023] The Hall element 4 detects the S pole, - the output when is delivered selector S1 is other control signals of the polarity inversion after input via a resistor R 8 to the input terminal transistor Q1, After being input to the base of Q3, the polarity is inverted to a signal as shown in FIG. 2E by an inverting amplifier composed of an operational amplifier OP4 and resistors R6 and R7, and then input to the bases of transistors Q2 and Q4 via a resistor R9. Let it. That is, the transistors Q1 and Q3
, A negative control signal is input to the bases thereof, and a positive control signal is input to the bases of the transistors Q2, Q4. Therefore , the internal resistance between the collector and the emitter of the transistors Q2 and Q3 changes in response to the control signal, and the voltage from the power supply 5 is adjusted by the transistors Q2 and Q3 and applied to the motor coil 3.

That is, when the Hall element 4 detects the N pole, the current flows from the point a to the point b via the motor coil, and when the S pole is detected, the current flows from the point b to the point a.

Accordingly, the direction of the current flowing through the motor coil is switched according to the rotational position of the rotor 1, so that the rotor 1 rotates continuously in the same direction, and the internal resistance of the bridge circuit varies in response to the control signal, so that the motor 1 The rotation speed can be controlled by a control signal.

[0026]

As described above, according to the present invention, the bridge
The internal resistance of the transistors that make up the circuit
The value of the voltage applied to the motor coil is
The rotation speed can be changed, and
The voltage applied to the coil can be a square wave
Voltage control to change the motor speed.
It is not necessary to provide a separate transistor for
The power loss caused by the saturation voltage of the
And the power loss that occurs when driving the motor
Can also be reduced, and with it,
The motor can be driven to rotate.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing an electric configuration of a motor control device according to one embodiment of the present invention.

FIG. 2 is a waveform chart showing each operation of the motor control device according to one embodiment of the present invention.

FIG. 3 is an explanatory diagram showing an internal configuration of a motor.

FIG. 4 is an explanatory diagram showing an electrical configuration of a motor control device as a conventional example.

FIG. 5 is a waveform chart showing each operation of a motor control device as a conventional example.

[Explanation of symbols]

 Reference Signs List 1 rotor 2 fixed armature 3 motor coil 4 hall element 5 power supply 6 signal transmission section 7 brand

Claims (1)

(57) [Claims] 1. A motor control device for continuously rotating the rotor in the same direction by switching forward and reverse in response to current supplied to the motor coil by a configured bridge circuit to the rotational position of the rotor by the transistor, the rotor Sends a control signal to change the rotation speed
Signal transmitting means, detecting means for detecting the rotational position of the rotor, and the signal transmitting means based on a detection signal from the detecting means.
Switching the control signal sent from the
Then, the above control signal is switched by the switched control signal.
Control means for controlling the driving of the ridge circuit, while the bridge circuit is provided based on the control signal.
Change the internal resistance of the transistor and mark on the motor coil.
A motor control device wherein the value of a voltage to be applied is varied .