JP3200278B2 - Motor controller - 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 controller for controlling a DC motor such as a DC motor for an automobile door mirror, a DC motor for driving a wiper of an automobile, and a DC motor for driving a sunroof of an automobile.

[0002]

2. Description of the Related Art Conventionally, a motor controller used for controlling a DC motor for a door mirror of an automobile is composed of a relay, a capacitor, a resistor, and a positive characteristic thermistor called a posistor. When a positive or negative input voltage is input and a relay is turned on, the motor controller drives a DC motor for a door mirror, which can be rotated forward and backward, in one direction to store a door mirror of an automobile or put it in use. When an excessive lock current flows due to a return or a state in which the DC motor for the door mirror is restrained, the relay is turned off by increasing the resistance value of the posistor and the DC motor for the door mirror is stopped. This motor controller can also be used to control a DC motor such as a DC motor for driving a wiper of an automobile and a DC motor for driving a sunroof of an automobile.

[0003]

In the above motor controller, when a positive or negative input voltage is input and a relay is turned on, a DC motor for a door mirror which can be rotated forward and reverse is driven in one of the directions. When the door mirror is retracted or returned to the use state, and the door mirror DC motor is in a locked state and an excessive lock current flows, the relay is turned off by increasing the resistance of the posistor and the door mirror DC motor stops. So
If the positive input voltage and the negative input voltage are repeatedly input at short time intervals because the temperature of the posistor does not decrease rapidly, the temperature of the posistor remains elevated and the current of the DC motor is limited to a small value. As a result, the control of the DC motor is disabled and the control of the door mirror is disabled. Further, since a relay having mechanical contacts is used, the life of the relay is short and reliability is low.

[0004] It is an object of the present invention to provide a motor controller which can solve the above problems and can always control a DC motor accurately and improve reliability.

[0005]

In order to achieve the above object, according to the first aspect of the present invention, a first input terminal and a second input terminal to which positive and negative input voltages are inputted, and both ends of the first and second input terminals are provided. A first semiconductor switching element that is connected to the first input terminal and one terminal of the DC motor and is turned on when a negative input voltage is input, and both ends of which are connected to the second input terminal and the other terminal of the DC motor. A second semiconductor switching element that is connected and turned on when a positive input voltage is input, a first capacitor connected between an input terminal of the second semiconductor switching element and the first input terminal, A first resistor connected between the second input terminal and an input terminal of the second semiconductor switching element; and a first resistor connected in parallel with the first resistor and through which a discharge current of the first capacitor flows.
Rectifier element, a first discharge current limiting resistor connected in series with the first capacitor, and connected between an input terminal of the first semiconductor switching element and the second input terminal. A second capacitor, a second resistor connected between the first input terminal and the input terminal of the first semiconductor switching element, and a second resistor connected in parallel with the second resistor. A second rectifier element through which the discharge current of the capacitor flows, a second discharge current limiting resistor connected in series with the second capacitor, and one terminal of the DC motor and the first input terminal. A third rectifying element connected between the third input terminal, a fourth rectifying element connected between the other terminal of the DC motor and the second input terminal, and a positive input voltage applied to the first input terminal. Input between the terminal and the second input terminal A first current detection resistor for detecting a current flowing through the third rectifying element, the DC motor and the second semiconductor switching element, and a first integration circuit for integrating a detection voltage of the first current detection resistor. And the integrated voltage of the first integration circuit, which is connected in parallel with the first resistor, is turned on when the integrated voltage becomes a predetermined level or more, and turns off the second semiconductor switching element. A third semiconductor switching element, the first semiconductor switching element, the DC motor and the fourth semiconductor switching element when a negative input voltage is input between the first input terminal and the second input terminal; A second current detecting resistor for detecting a current flowing through the rectifying element of
A second integration circuit for integrating the detection voltage of the current detection resistor, and an integration voltage of the second integration circuit, which is connected in parallel with the second resistance, and is higher than a predetermined level. And a fourth semiconductor switching element for turning on the first semiconductor switching element.

[0006]

When a positive input voltage is input between the first input terminal and the second input terminal, the input voltage is input to the input terminal of the second semiconductor switching element through the first capacitor. As a result, the second semiconductor switching element is turned on, current flows through the third rectifying element, the DC motor, and the second semiconductor switching element, and the DC motor rotates in one direction. The first current detection resistor detects a current flowing through a third rectifying element, the DC motor, and the second semiconductor switching element, and a detection voltage of the first current detection resistor is integrated by a first integration circuit. You. The third semiconductor switching element is turned on when the integrated voltage of the first integrating circuit is input and the integrated voltage becomes a predetermined level or more, and turns off the second semiconductor switching element. Further, the input voltage of the second semiconductor switching element decreases as the first capacitor is charged, and is turned off when the first capacitor is charged to a predetermined level. The DC motor stops when the second semiconductor switching element is turned off, and the first capacitor discharges through the second rectifying element and the first discharge current limiting resistor.

When a negative input voltage is input between the first input terminal and the second input terminal, the input voltage is input to the input terminal of the first semiconductor switching element through the second capacitor. As a result, the first semiconductor switching element is turned on, a current flows through the fourth rectifying element, the DC motor, and the first semiconductor switching element, and the DC motor rotates in the reverse direction. The second current detection resistor detects a current flowing through the fourth rectifying element, the DC motor, and the first semiconductor switching element, and a detection voltage of the second current detection resistor is integrated by a second integration circuit. The fourth semiconductor switching element is turned on when the integrated voltage of the second integration circuit is input and the integrated voltage becomes equal to or higher than a predetermined level, and turns off the first semiconductor switching element. Further, the input voltage of the first semiconductor switching element decreases as the second capacitor is charged, and is turned off when the second capacitor is charged to a predetermined level. The DC motor stops when the second semiconductor switching element is turned off, and the second capacitor discharges through the first rectifying element and the second discharge current limiting resistor.

[0008]

FIG. 1 shows an embodiment of the present invention. In this embodiment, semiconductor switching elements 21 and 22 composed of MOS field effect transistors, NPN transistors 23 and 24, rectifying elements 25 to 28 composed of diodes, capacitors 29 to 32, resistors 33 to 4
And input terminals 43 and 44 are connected to switches 45 and 46
Is connected to each of the movable sections. Switches 45, 46
Are fixedly connected to each other by an operation section of a driver's seat in an automobile. One of the fixed terminals 45a and 46b is connected to each other and connected to one output terminal of a battery in the automobile, and the other fixed terminals 45b and 46b are connected to each other. 46a are connected to each other and to the other output terminal of the battery in the vehicle. The resistors 39 and 40 are current detection resistors, and the resistors 33 and 34 are discharge current limiting resistors. The capacitor 31 and the resistor 41 constitute an integrating circuit, and the capacitor 32
The resistor 42 also forms an integrating circuit.

The MOS type field effect transistor 2
1 and 22 may use another semiconductor switching element, and the NPN transistors 23 and 24 may also use another semiconductor switching element. In addition, diodes 25 to
28 may use another rectifying element. The direct current motor 47 for the vehicle door mirror is used to store the door mirror and return to the use state by forward and reverse rotation. For example, the DC motor 47 stores the door mirror in the vehicle by reverse rotation and returns the door mirror to the use state by forward rotation.

The input terminal 43 is directly connected to the anode of the diode 25 and connected to the source of the field effect transistor 21 via the current detecting resistor 39. The input terminal 44 is directly connected to the anode of the diode 26. Field effect transistor 2 via current detection resistor 40
2 sources. The cathode of the diode 25 and the drain of the field effect transistor 21 are connected to one terminal of a DC motor 47 for an automobile door mirror, and the cathode of the diode 26 and the drain of the field effect transistor 22 are connected to the other terminal of the DC motor 47 for an automobile door mirror. Is done.

A resistor 3 is provided between the input terminals 43 and 44.
3, the capacitor 29 and the resistor 36 are connected in series, and the resistor 35, the capacitor 30 and the resistor 34 are connected in series. The anode of the diode 27 and the emitter of the transistor 23 are connected to the input terminal 43, and the cathode of the diode 27 and the collector of the transistor 23 are connected to a connection point between the resistor 35 and the capacitor 30. The gate serving as the input terminal of the field effect transistor 21 is a resistor 37
Is connected to a connection point between the resistor 35 and the capacitor 30, and a base serving as an input terminal of the transistor 23 is connected to a connection point between the capacitor 31 and the resistor 41. The capacitor 31 and the resistor 41 are connected in series between both ends of the current detection resistor 39, and the capacitor 31 is connected between the base and the emitter of the transistor 23.

An anode of the diode 28 and an emitter of the transistor 24 are connected to an input terminal 44, and a cathode of the diode 28 and a collector of the transistor 24 are connected to a connection point between the capacitor 29 and the resistor 36. The gate serving as the input terminal of the field effect transistor 22 is a resistor 3
8, a connection point between the capacitor 29 and the resistor 36 is connected, and a base serving as an input terminal of the transistor 24 is connected to a connection point between the capacitor 32 and the resistor 42. The capacitor 32 and the resistor 42 are connected in series between both ends of the current detection resistor 40, and the capacitor 32 is connected between the base and the emitter of the transistor 24. Note that the capacitor 2
A discharge resistor may be connected in parallel with 9, 30.

Next, the operation of this embodiment will be described. When the movable sections of the switches 45 and 46 are switched to the fixed terminals 45a and 46a, the switch 4
When a positive voltage is input to the input terminals 43 and 44 via the fixed terminals 45a and 46a and the movable segments, and the movable segments of the switches 45 and 46 are switched to the fixed terminals 45b and 46b, the battery of the vehicle To switch 45,
A negative voltage is input to the input terminals 43 and 44 via the fixed terminals 45b and 46b and the movable segment.

When the switches 45 and 46 are switched to input a positive voltage to the input terminals 43 and 44, the input voltage is input to the gate of the field effect transistor 22 via the resistor 33, the capacitor 29 and the resistor 38. The field effect transistor 22 is turned on, and the diode 2
5, a current flows through the DC motor 47, the field effect transistor 22, and the current detection resistor 40, the DC motor 47 rotates forward, and the door mirror is returned to the use state.

In this case, as shown in FIG. 2, the current flowing through the DC motor 47 temporarily increases at the time of rising and then becomes a normal drive current value. When the state is restricted, the current value becomes excessive. However, the DC motor 4
7 is detected by a current detection resistor 40 and converted into a voltage.
And is added between the base and the emitter of the transistor 24.

When the integrated voltage of the integrating circuit, that is, the voltage of the capacitor 32 rises above a predetermined level, the transistor 24 turns on, the field effect transistor 22 turns off, and the DC motor 47 stops. Therefore, when the current flowing through the DC motor 47 becomes a predetermined value or more, the transistor 24 and the field-effect transistor 22 are turned off, the DC motor 47 is stopped, and no excessive current flows through the DC motor 47, so that the DC motor 47 is protected. You.

At the time of rising, a large current temporarily flows through the DC motor 47 as shown in FIG. 2, but at this time, the integration circuit 32 and the integrating circuit 32 are turned on so that the transistor 24 is not turned on.
42 time constants are set. Therefore, at the time of rising, the integrated voltages of the integration circuits 32 and 42 do not exceed a predetermined level, and the transistor 24 does not turn on. The capacitor 29 is charged by the input voltage through the resistors 33 and 36. When the capacitor 29 is charged to a predetermined level, the field effect transistor 22 is turned off and the DC motor 47 is turned off.
Stops. Also, the capacitor 30 discharges through the diode 27 and the resistor 34.

When the switches 45 and 46 are switched to input a negative voltage to the input terminals 43 and 44, similarly,
The input voltage is input to the gate of the field effect transistor 21 via the resistor 34, the capacitor 30, and the resistor 37, and the field effect transistor 21 is turned on. The diode 26, the DC motor 47, and the field effect transistor 2
A current flows through 1 and the current detection resistor 39, the DC motor 47 rotates in the reverse direction, and the door mirror is retracted.

In this case, the current flowing through the DC motor 47 temporarily increases at the time of rising and then becomes a normal current value, and the reverse rotation of the door mirror is fully performed, so that the DC motor 47 is restrained. Sometimes the current value is excessive. However, the current flowing through the DC motor 47 is detected by the current detecting resistor 39 and converted into a voltage. This voltage is integrated by an integrating circuit including the capacitor 31 and the resistor 41 and applied between the base and the emitter of the transistor 23.

When the integral voltage of the integrating circuit, that is, the voltage of the capacitor 31 rises above a predetermined level, the transistor 23 turns on, the field effect transistor 21 turns off, and the DC motor 47 stops. Therefore, when the current flowing through the DC motor 47 is equal to or more than a predetermined value, the transistor 23 and the field effect transistor 21 are turned off, the DC motor 47 is stopped, and the DC motor 47 is protected without an excessive current flowing through the DC motor 47. You.

At the time of rising, a large current temporarily flows through the DC motor 47.
The time constant of the integration circuits 31 and 41 is set so that 3 does not turn on. Therefore, at the time of rising, the integration circuit 3
The integrated voltages of 1, 41 do not exceed a predetermined level, and the transistor 23 does not turn on. The capacitor 30 is charged by the input voltage through the resistors 34 and 35. When the capacitor 30 is charged to a predetermined level, the field effect transistor 21 turns off and the DC motor 47 stops. Further, the capacitor 29 discharges through the diode 28 and the resistor 33.

In this embodiment, even when the switches 43 and 44 are repeatedly switched at short time intervals, the DC motor 47 can be accurately controlled and a semiconductor switching element is used without using mechanical contacts. This extends the life and increases reliability. The present invention is not limited to the above-described embodiment, and can be applied to a motor controller that controls a DC motor such as a DC motor for driving a wiper of an automobile and a DC motor for driving a sunroof of an automobile.

[0023]

As described above, according to the first aspect of the present invention, the first input terminal and the second input terminal to which positive and negative input voltages are input, and both ends of the first input terminal. And a first semiconductor switching element connected to one terminal of the DC motor and turned on when a negative input voltage is input, and a positive input voltage connected at both ends to the second input terminal and the other terminal of the DC motor. A second semiconductor switching element that is turned on at the time of input, a first capacitor connected between an input terminal of the second semiconductor switching element and the first input terminal, and a second input terminal; A first resistor connected between an input terminal of the second semiconductor switching element, a first rectifier connected in parallel with the first resistor, and through which a discharge current of the first capacitor flows; The first
A first discharging current limiting resistor connected in series with the first capacitor, a second capacitor connected between an input terminal of the first semiconductor switching element and the second input terminal, A second resistor connected between the first input terminal and the input terminal of the first semiconductor switching element; and a second resistor connected in parallel with the second resistor and through which the discharge current of the second capacitor flows. A rectifier element, a second discharge current limiting resistor connected in series with the second capacitor, and a third connected between one terminal of the DC motor and the first input terminal. A rectifier element, a fourth rectifier element connected between the other terminal of the DC motor and the second input terminal, and a positive input voltage between the first input terminal and the second input terminal. The third rectifying element, A first current detection resistor for detecting a current flowing through the DC motor and the second semiconductor switching element; a first integration circuit for integrating a detection voltage of the first current detection resistor; A third semiconductor switching element which is connected in parallel, turns on the second semiconductor switching element when the integrated voltage of the first integrating circuit is inputted and the integrated voltage becomes a predetermined level or more, and Detecting a current flowing through the first semiconductor switching element, the DC motor, and the fourth rectifying element when a negative input voltage is input between the first input terminal and the second input terminal; A second current detection resistor, a second integration circuit for integrating the detection voltage of the second current detection resistor, and a product of the second integration circuit connected in parallel with the second resistor. A fourth semiconductor switching element for turning on the first semiconductor switching element when a voltage is input and the integrated voltage becomes equal to or higher than a predetermined level and for turning off the first semiconductor switching element, so that the DC motor can always be accurately controlled. , Reliability can be improved.

[Brief description of the drawings]

FIG. 1 is a circuit diagram showing one embodiment of the present invention.

FIG. 2 is a diagram showing a drive current of a DC motor.

[Explanation of symbols]

 21, 22 Field-effect transistor 23, 24 Transistor 25-28 Diode 29-32 Capacitor 33-42 Resistance 43, 44 Input terminal

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-2-285985 (JP, A) JP-A-63-302793 (JP, A) JP-A-59-72995 (JP, A) JP-A-1- 1488693 (JP, A) Japanese Utility Model 52-91036 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) H02P 5/00-5/26 H02P ⁷ /00-7/34 B60R 1/06

Claims (1)

(57) [Claims] 1. A first input terminal and a second input terminal to which positive and negative input voltages are input, and a negative input voltage having both ends connected to the first input terminal and one terminal of a DC motor. A first semiconductor switching element that is turned on at the time of input, a second semiconductor switching element that is connected at both ends to the second input terminal and the other terminal of the DC motor, and that is turned on when a positive input voltage is input, A first capacitor connected between an input terminal of a second semiconductor switching element and the first input terminal; and a first capacitor connected between the second input terminal and the input terminal of the second semiconductor switching element. A first resistor connected thereto, a first rectifier element connected in parallel with the first resistor and through which a discharge current of the first capacitor flows,
A first discharging current limiting resistor connected in series with the first capacitor, and a second discharging current limiting resistor connected between the input terminal and the second input terminal of the first semiconductor switching element.
And a second capacitor connected between the first input terminal and the input terminal of the first semiconductor switching element.
, A second rectifier element connected in parallel with the second resistor, through which the discharge current of the second capacitor flows, and a second discharge current limiting resistor connected in series with the second capacitor. A third rectifying element connected between one terminal of the DC motor and the first input terminal; and a third rectifying element connected between the other terminal of the DC motor and the second input terminal. And a third rectifier element, the DC motor and the second rectifier element when a positive input voltage is input between the first input terminal and the second input terminal. A first current detection resistor that detects a current flowing through the semiconductor switching element; a first integration circuit that integrates a detection voltage of the first current detection resistor; and a first integration circuit connected in parallel with the first resistance. The integration voltage of the integration circuit is input and this integration voltage is A third semiconductor switching element that turns on when the level exceeds a certain level to turn off the second semiconductor switching element, and that a negative input voltage is applied between the first input terminal and the second input terminal. And a second current detection resistor for detecting a current flowing through the first semiconductor switching element, the DC motor, and the fourth rectifier element, and integrating a detection voltage of the second current detection resistor. A second integration circuit, which is connected in parallel with the second resistor, receives an integrated voltage of the second integration circuit, and turns on when the integrated voltage becomes equal to or higher than a predetermined level. A motor controller comprising: a fourth semiconductor switching element for turning off the semiconductor switching element.