JP2000287471A - Motor drive control circuit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a motor drive control circuit which is free from malfunctioning and can control the drive of the motor securely. SOLUTION: A lead relay L whose drive coil LC is excited by a locking current generated when a motor M is locked and whose lead switch LS is turned on/off by the excited drive coil LC, and a relay circuit Re whose exciting coil RC is demagnetized when the lead switch LS is turned on/off and whose movable contact RS is turned off by the demagnetization of the exciting coil RC to cut off current application to the motor M, are provided. As a result, the locking state of the motor M is detected by the lead relay L and the current application to the motor M is cut off by the relay circuit Re in accordance with the detection of the lead relay L. Therefore, the locking state of the motor M can be judged clearly without variation in comparison with the judgement in the case of current control using electronic components, so that the drive of the motor M can be controlled securely without malfunctioning.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a circuit for controlling the driving of motors such as a motor for an electric retractable door mirror, a motor for a power window, a motor for a power seat and a motor for a power antenna of an automobile. More particularly, the present invention relates to a motor drive control circuit that can surely perform drive control of a motor without malfunction, that is, can surely shut off power supply to the motor.

[0002]

2. Description of the Related Art An electric retractable door mirror of an automobile, for example, as an apparatus equipped with a motor drive control circuit of this type will be described below with reference to FIG. In FIG. 5, reference numeral 1 denotes a mirror base fixed to a door (not shown) of an automobile. The mirror base 1 is equipped with an electronic unit 2.

The electronic unit 2 includes a shaft holder 20 fixed to the mirror base 1 and a shaft 21 provided (fixed) integrally with the shaft holder 20.
A gear case 22 and a cover 23 rotatably mounted around the axis of the shaft 21 on the fixed member side of the shaft 21 and the shaft holder 20, a motor M housed in the cover 23 and the gear case 22; And a speed reduction mechanism 24 and a clutch mechanism 25.
The speed reduction mechanism 24 and the clutch mechanism 25 described above are interposed between the motor M and the shaft 21. A stopper mechanism (not shown) is interposed between the rotating member side and the fixed member side of the gear case 22 and the like (cover 23, motor M, reduction mechanism 24, clutch mechanism 25) of the electronic unit 2. ing. A mirror assembly 3 is attached to the rotating member.

The mirror assembly 3 includes a mirror body 30 having a mirror surface (mirror surface) on a front surface, and a heater (for example, PT) provided on the back surface of the mirror body 30.
It comprises a C-plane heating element 31, a mirror holder 32, a mirror housing 33 having an opening on the front surface, and a power unit 34 mounted in the mirror housing 33. The above-mentioned mirror body 30 and the like (including the heater 31 and the mirror holder 32) are attached to the above-mentioned power unit 34 so as to be tiltable up, down, left and right, and are arranged at the front opening of the above-mentioned mirror housing 33.

The above-mentioned mirror base 1 and electronic unit 2
A door mirror is composed of the mirror assembly 3 (including a fixed member, a rotating member, a motor M, and the like). The door mirrors are attached to the left and right doors of the vehicle, respectively.

Here, when the motor M is energized, the motor M is driven and the driven object moves, and in this example, the mirror assembly 3 rotates from the standing position to the storage position or from the storage position to the standing position. . When the mirror assembly 3 reaches a predetermined storage position or a standing position, the mirror mechanism 3 is physically immovable by the stopper mechanism, and the motor M is locked. At this time, by the operation of the motor drive control circuit (not shown), the power supply to the motor M is cut off, the drive of the motor M is stopped, and the mirror assembly 3 is stopped at the predetermined storage position or the upright position. I do. An example of this type of motor drive control circuit is disclosed in Japanese Patent Application Laid-Open No. 10-285005.

[0007]

However, the above-mentioned conventional motor drive control circuit uses a so-called electronic component, which detects when the motor M is locked and cuts off the power supply to the motor M by using the electronic component. It is a current control type. For this reason, depending on the capacity of the motor M, there may be variations in detection when the motor M is locked or when power is cut off to the motor M,
In addition, the threshold value of the electronic component changes due to dust, water, and the like. As a result, there is a risk of malfunction, and there is a problem in reliably controlling the drive of the motor, that is, shutting off the power supply to the motor.

An object of the present invention is to provide a motor drive control circuit capable of reliably performing motor drive control without malfunction.

[0009]

According to the present invention, in order to achieve the above object, a drive coil is excited by a lock current generated when a motor is locked, and a reed switch is turned on.
Or a reed relay that turns off, and a relay circuit that turns off a movable contact when a reed switch of the reed relay is turned on or off to turn off a movable contact and cut off power supply to the motor. I do.

As a result, the motor drive control circuit of the present invention detects the locked state of the motor by the reed relay,
By the relay circuit based on the detection of this reed relay,
Since the current supply to the motor is cut off, the determination of the locked state of the motor is less scattered and clear as compared with the current control by electronic components. For this,
The drive control of the motor can be reliably performed without malfunction.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Three examples of the embodiment of the motor drive control circuit according to the present invention will be described below with reference to FIGS. FIG. 1 is a circuit diagram showing a first embodiment of the motor drive control circuit of the present invention. This example describes a motor drive control circuit for an electrically retractable door mirror of a motor vehicle that rotates a mirror assembly from a standing position to a storage position or from a storage position to a standing position. In the figure, the same reference numerals as those in FIG.

As shown in FIG. 1, a motor drive control circuit (a circuit composed of a motor M, a reed relay L, a relay circuit Re, and the like) of the present invention in the first embodiment is a polarity converter for changing the polarity of a power supply. It is electrically connected to an electrical switch (not shown) of the switch mechanism via connectors A1, A2 and the like.

That is, one terminal A1 of this connector is connected to one terminal X of a motor M by a positive temperature coefficient thermistor PTC described later.
The other terminal A2 of the connector is connected to the other terminal Y of the motor M via a drive coil LC of a reed relay L described later.

The above-mentioned positive temperature coefficient thermistor PTC is an element that increases the resistance value when the circuit is short-circuited and reduces the circuit current, and may or may not be provided particularly at a position other than that shown in FIG.

In FIG. 1, Re is a relay circuit.
The relay circuit Re has an exciting coil RC and an ON state when the exciting coil RC is in an excited state to energize the motor M, and an OFF state when the exciting coil RC is in a demagnetized state. The motor M includes a movable contact RS for interrupting power supply to the motor M, and a resistor RR for self-holding a relay for holding the exciting state of the exciting coil RC.

One terminal of the excitation coil RC is connected to one terminal A1 of the connector and the positive temperature coefficient thermistor PTC via a starting capacitor C, and the other terminal of the excitation coil RC is connected to the connector. Connected to the other terminal A2. One terminal of the movable contact RS is connected to one terminal A1 of the connector and the positive temperature coefficient thermistor PTC, and the other terminal of the movable contact RS is connected to one terminal X of the motor M. I have. Further, one terminal of the resistor RR is connected between the capacitor C and the exciting coil RC, and another terminal of the resistor RR is connected between the movable contact RS and one terminal X of the motor M. Have been.

In FIG. 1, L is a reed relay.
The reed relay L includes a drive coil LC whose magnetic field strength is increased by a lock current generated when the motor M is locked, and a drive coil LC whose magnetic field strength is increased by the lock current. Turn on the excitation coil R
A normally open type reed switch LS in which the excitation state of C is in a demagnetized state, and a situation in which the strength of the magnetic field of the drive coil LC is increased by the rush current when the motor M is started and the reed switch LS is turned on. And a capacitor CN for erasing the motor rush current for prevention. The above-mentioned drive coil LC is wound independently and is arranged close to the above-mentioned reed switch LS. Note that the above-described motor rush current erasing capacitor CN is unnecessary if the reed switch LS is not turned on even if the strength of the magnetic field of the drive coil LC becomes large to some extent due to the rush current when the motor M is started. is there.

One terminal of the drive coil LC is connected to the other terminal Y of the motor M, and the other terminal of the drive coil LC is connected to the other terminal A2 of the connector. Further, the above-described reed switch LS is connected in parallel to the excitation coil RC. Further, the above-mentioned motor rush current elimination capacitor CN is connected in parallel to the drive coil LC.

In FIG. 1, R is a resistor for discharging the starting capacitor C. One terminal of this discharge resistor R is
The other terminal of the discharging resistor R is connected to one terminal A1 of the connector and the positive temperature coefficient thermistor PTC.
The connector is connected to the other terminal A2 side. The potentials applied to both terminals A1 and A2 of the connector are reverse voltages applied during storage and recovery, and each time the capacitor C
Is discharged, the capacitor C
Is unnecessary. However, when the discharge resistor R is provided, the capacitor C in the storage direction or the return direction may not be activated when the capacitor C is operated in the same direction in the storage direction or the return direction. Can be prevented, and the reliability is improved.

Although the above-mentioned motor drive control circuit is shown in one of the left and right mirror assemblies 3, the same motor drive control circuit is actually provided in other mirror assemblies. Have been.

Next, the operation of the motor drive control circuit according to the first embodiment of the present invention will be described. First, operate the electronic switch to connect both terminals A1,
A voltage is applied to A2. For example, when operating the return rotation, a positive voltage is applied to one terminal A1 and a negative voltage is applied to the other terminal A2. Then, at the moment of the voltage application, a current flows from one terminal A1 of the connector → the positive characteristic thermistor PTC → the capacitor C → the exciting coil RC → the other terminal A2 of the connector. At this time, since the excitation coil RC that has been in the demagnetized state is in the excited state, the movable contact RS that has been in the OFF state is turned on. For this reason, one terminal A1 of the connector →
Positive thermistor PTC → movable contact RS → motor M → drive coil LC and motor rush current elimination capacitor CN
→ Current also flows through the path of the other terminal A2 of the connector. As a result, a current flows in the motor M in the direction indicated by the solid arrow, and the motor M
Rotates forward, and the mirror assembly 3 returns and rotates from the storage position to the standing position.

Then, when a predetermined time has elapsed, the capacitor C is charged, and no current is supplied from the capacitor C to the exciting coil RC. However, since a part of the current from the movable contact RS flows through the self-holding resistor RR, the exciting coil RC, and the other terminal A2 of the connector, the current in the above-described path is excited. State is self-maintained. As a result, even when no current is supplied from the capacitor C, the excited state of the exciting coil RC is held by itself, so that the movable contact RS maintains the ON state, and the motor M continues to rotate forward.

The value of the magnetic field strength of the drive coil LC for turning on the above-described reed switch LS (impression value)
Is defined by the product of the number of coil turns and the current value in the coil, and is set to be obtained by a lock current generated when the motor M is locked. For this reason, even if a current flows through the drive coil LC during the rotation of the motor M, the reed switch LS is turned off since the strength of the magnetic field of the drive coil LC is smaller than the impressed value. And the exciting coil RC is in the excited state. Also, even if an inrush current occurs when the motor M starts,
Since the inrush current is erased by the motor inrush current erase capacitor CN, the strength of the magnetic field of the drive coil LC is
Since the state is smaller than the impression value, the reed switch LS
Is in the OFF state, and the exciting coil RC is in the excited state.

When the mirror assembly 3 reaches a predetermined standing position, the mirror mechanism 3 is physically immovable by the stopper mechanism, the motor M is locked, and the forward rotation of the motor M is stopped. At the same time,
The current flowing in the above-described path becomes large due to the lock current due to the lock of the motor M (for example, the current during normal operation is 0.
25A and the lock current is 1.5A). Since this lock current flows through the drive coil LC, the strength of the magnetic field of the drive coil LC becomes larger than the impressed value, and the reed switch LS is turned on. As a result, the exciting coil R
Since the current flowing to the C side is short-circuited to the reed switch LS side, the exciting coil RC which has been in the excited state is demagnetized. Accordingly, the movable contact RS that has been in the ON state is turned off, and the power supply to the motor M is cut off. That is, no current (lock current) flows through the motor M in the above-described path, and the return rotation operation of the mirror assembly 3 is completed.

Here, when the voltage applied between both terminals A1 and A2 of the connector disappears, the electric charge charged in the starting capacitor C is discharged via the discharging resistor R.

Next, when performing a storing operation, a negative voltage is applied to one terminal A1 and a positive voltage is applied to the other terminal A2.
Other terminal A2 of connector → Excitation coil RC → Capacitor C
→ Positive characteristic thermistor PTC → Current flows to one terminal A1 of the connector. At this time, the exciting coil RC is excited and the movable contact RS is turned on, so that the other terminal A2 of the connector → the drive coil LC and the capacitor CN for eliminating the inrush current of the motor → the motor M → the movable contact RS → the positive characteristic. Current also flows through the path from the thermistor PTC to one terminal A1 of the connector. As a result, a current flows in the motor M in the direction of the dashed arrow, and the motor M rotates in the reverse direction, and the mirror assembly 3 rotates from the standing position to the storage position.

Then, when a predetermined time has elapsed, the capacitor C is charged, and no current is supplied from the capacitor C to the exciting coil RC. A part of the current of the excitation coil RC → the self-holding resistor RR → the movable contact RS →
Since the current flows from the positive characteristic thermistor PTC to one terminal A1 of the connector, the excitation state of the excitation coil RC is maintained by itself. As a result, even when no current is supplied from the capacitor C, the excited state of the exciting coil RC is maintained by itself, so that the movable contact RS maintains the ON state, and the motor M continues to rotate in the reverse direction.

Even if a current flows through the drive coil LC during the rotation of the motor M, the reed switch LS is turned off since the strength of the magnetic field of the drive coil LC is smaller than the impressed value. State, and even if an inrush current occurs when the motor M is started, the strength of the magnetic field of the drive coil LC is smaller than the impressed value due to the action of the motor inrush current canceling capacitor CN. The reed switch LS is in the OFF state. As a result, the exciting coil RC is in the excited state, and there is no possibility that the operation of the circuit will cause any trouble.

When the mirror assembly 3 reaches the storage position at a predetermined position, the mirror assembly 3 is physically immovable by the stopper mechanism, the motor M is locked, and the reverse rotation of the motor M is stopped. At the same time,
Since the current flowing in the above-described path becomes large due to the lock current due to the lock of the motor M, the strength of the magnetic field of the drive coil LC becomes larger than the impressed value, and the reed switch LS
N. As a result, the current flowing to the exciting coil RC side is short-circuited to the reed switch LS side, so that the exciting coil RC is in a demagnetized state, the movable contact RS is in an OFF state, and the power supply to the motor M is cut off. The current (lock current) stops flowing through the motor M, and the return rotation operation of the mirror assembly 3 is completed.

Here, when the voltage applied between both terminals A1 and A2 of the connector disappears, the electric charge charged in the starting capacitor C is discharged through the discharging resistor R.

As described above, the motor drive control circuit of the present invention in the first embodiment detects the locked state of the motor M by the reed relay L including the drive coil LC and the reed switch LS, and detects the reed relay L. The energization to the motor M is cut off by a relay circuit Re including an exciting coil RC, a movable contact RS, and a self-holding resistor RR based on the following equation. Compared with, there is no variation and it is clear. Therefore, the drive control of the motor M can be reliably performed without malfunction.

FIG. 2 shows a first embodiment of the motor drive control circuit according to the present invention.
FIG. 9 is a circuit diagram showing a modification of the embodiment. This modified example has the circuit diagram shown in FIG. 1 described above, that is, the drive coil LC is wound separately and independently of the reed switch LS, and is arranged close to the reed switch LS. On the other hand, the drive coil LC is wound around the outside of the reed switch LS, and the same operation and effect as those of the circuit diagram shown in FIG. 1 can be achieved.

FIG. 3 shows a second embodiment of the motor drive control circuit according to the present invention.
FIG. 2 is a circuit diagram illustrating the embodiment. In the drawing, the same reference numerals as those in FIGS. 1, 2 and 5 denote the same components. The motor drive control circuit of the present invention in the second embodiment uses a normally closed reed switch LS 'and eliminates the motor inrush current erasing capacitor CN.

The above-described reed switch LS 'is normally in the ON state (when the strength of the magnetic field of the drive coil LC is smaller than the moving value), and the strength of the magnetic field of the driving coil LC is larger than the moving value. Then, the transistor is turned off and is connected in series to the self-holding resistor RR. That is, one terminal of the reed switch LS 'is connected to the other terminal of the self-holding resistor RR, and the other terminal of the reed switch LS' is connected between the movable contact RS and one terminal X of the motor M. It is connected to the.

The starting capacitor C has a capacitance value that can prevent malfunction due to the rush current of the motor M. That is, when the power is turned on, when the motor M starts rotating, a high current (rush current) momentarily flows through the circuit, and the strength of the magnetic field of the drive coil LC becomes larger than the impressed value, so that the reed switch LS ' During this time (while the inrush current is flowing in the circuit), the starting capacitor C having a capacitance value enough to excite the exciting coil RC through the starting capacitor C is used.

Next, the operation of the motor drive control circuit according to the second embodiment of the present invention will be described. First, operate the electronic switch to connect both terminals A1,
A voltage is applied to A2. For example, when operating the return rotation, a positive voltage is applied to one terminal A1 and a negative voltage is applied to the other terminal A2. Then, at the moment of the voltage application, a current flows from one terminal A1 of the connector → the positive characteristic thermistor PTC → the capacitor C → the exciting coil RC → the other terminal A2 of the connector. At this time, since the excitation coil RC that has been in the demagnetized state is in the excited state, the movable contact RS that has been in the OFF state is turned on. For this reason, one terminal A1 of the connector →
Current also flows through the path of the positive characteristic thermistor PTC → movable contact RS → motor M → drive coil LC → other terminal A2 of the connector. As a result, a current flows in the motor M in the direction of the solid line arrow, the motor M rotates forward, and the mirror assembly 3 returns to the standing position from the storage position and rotates.

When the power is turned on, when the motor M starts to rotate, a high current flows momentarily in the circuit, and the strength of the magnetic field of the drive coil LC becomes larger than the impressed value.
Even when S 'is in the OFF state, current is supplied to the exciting coil RC through the capacitor C during this time, so that the exciting coil RC is in the excited state.

Then, when the motor M rotates, the current value in the circuit decreases, so that the strength of the magnetic field of the drive coil LC becomes smaller than the impressed value, and the reed switch LS '
Changes from the OFF state to the ON state. When the reed switch LS 'is turned on, a part of the current from the movable contact RS, which is the current in the above-described path, is reed switch LS' → self-holding resistor RR → exciting coil R
Since the current flows from C to the other terminal A2 of the connector, the exciting state of the exciting coil RC is maintained by itself. As a result, even if the capacitor C is charged after a predetermined period of time and the current is no longer supplied from the capacitor C to the excitation coil RC, the excitation state of the excitation coil RC is maintained as described above. As a result, the movable contact RS maintains the ON state, and the motor M continues to rotate forward.

When the mirror assembly 3 reaches the predetermined standing position, the mirror mechanism 3 is physically immovable by the stopper mechanism, the motor M is locked, and the forward rotation of the motor M is stopped. At the same time,
The current flowing in the above-described path becomes large due to the lock current due to the lock of the motor M (for example, the current during normal operation is 0.
25A and the lock current is 1.5A). Since this lock current flows through the drive coil LC, the strength of the magnetic field of the drive coil LC becomes larger than the impressed value, and the reed switch LS 'is turned off. As a result, the current for self-holding flowing from the movable contact RS to the exciting coil RC side is cut off by the reed switch LS ', so that the exciting coil RC in the excited state is demagnetized. Accordingly, the movable contact RS that has been in the ON state is turned off, and the power supply to the motor M is cut off. That is, no current (lock current) flows through the motor M in the above-described path, and the return rotation operation of the mirror assembly 3 is completed.

Here, when the voltage applied between both terminals A1 and A2 of the connector disappears, the electric charge charged in the starting capacitor C is discharged through the discharging resistor R.

Next, when performing a storing operation, a negative voltage is applied to one terminal A1 and a positive voltage is applied to the other terminal A2.
Other terminal A2 of connector → Excitation coil RC → Capacitor C
→ Positive characteristic thermistor PTC → Current flows to one terminal A1 of the connector. At this time, the exciting coil RC is excited and the movable contact RS is turned on, so that the other terminal A2 of the connector → the drive coil LC → the motor M → the movable contact RS →
Current also flows through the path from the positive characteristic thermistor PTC to one terminal A1 of the connector. As a result, a current flows in the motor M in the direction of the dashed arrow, and the motor M rotates in the reverse direction, and the mirror assembly 3 rotates from the standing position to the storage position.

Then, when the motor M rotates, the current value in the circuit decreases, so that the strength of the magnetic field of the drive coil LC becomes smaller than the impressed value, and the reed switch LS '
Changes from the OFF state to the ON state. When the reed switch LS 'is turned on, a part of the current in the above-described path and from the other terminal A2 of the connector is changed from the exciting coil RC to the self-holding resistor RR to the reed switch L.
Since the current flows from S ′ → movable contact RS → positive temperature coefficient thermistor PTC → one terminal A1 of the connector, the excitation state of the excitation coil RC is self-held. As a result, even if the capacitor C is charged after a predetermined period of time and the current is no longer supplied from the capacitor C to the excitation coil RC, the excitation state of the excitation coil RC is maintained as described above. As a result, the movable contact RS maintains the ON state, and the motor M continues to rotate forward.

When the mirror assembly 3 reaches the storage position at the predetermined position, the mirror assembly 3 is physically immovable by the stopper mechanism, the motor M is locked, and the reverse rotation of the motor M is stopped. At the same time,
Since the current flowing in the above-described path is increased by the lock current due to the lock of the motor M, the strength of the magnetic field of the drive coil LC becomes larger than the impressed value, and the reed switch LS 'is turned off. As a result, the self-holding current flowing to the exciting coil RC side is cut off by the reed switch LS ', so that the exciting coil RC that has been in the excited state is demagnetized. Along with that, the movable contact RS that was in the ON state
Is turned off, the power supply to the motor M is cut off, and no current (lock current) flows through the motor M in the above-described path, and the return rotation operation of the mirror assembly 3 is completed.

Here, when the voltage applied between both terminals A1 and A2 of the connector disappears, the electric charge charged in the starting capacitor C is discharged via the discharging resistor R.

As described above, the motor drive control circuit of the present invention in the second embodiment can achieve the same functions and effects as those of the first embodiment. In particular, the second embodiment eliminates the need for a motor rush current elimination capacitor, and accordingly can reduce the number of components.

FIG. 4 shows a third embodiment of the motor drive control circuit according to the present invention.
FIG. 2 is a circuit diagram illustrating the embodiment. In the drawing, the same reference numerals as those in FIGS. 1, 2, 3, and 5 denote the same components. This third
The motor drive control circuit of the present invention in the embodiment is different from that of the second embodiment in that the delay means for delaying the excitation state of the excitation coil RC by a predetermined time after the reed switch LS 'is turned off is a reed relay L. It is provided in. This delay means comprises a capacitor C 'and a resistor R' connected in parallel with the reed switch LS '. The capacitor C 'and the resistor R' are connected in series.

Hereinafter, the operation of the third embodiment will be described. The operation of the third embodiment is different from that of the second embodiment in that the capacitor C '
And an operation of a delay means comprising a resistor R '.

That is, when the mirror assembly 3 is stopped at a predetermined position by the stopper mechanism, the lock current of the motor M flows through the circuit, so that the strength of the magnetic field of the drive coil LC becomes larger than the impressed value, and the reed switch LS ' Is OF
It becomes F. As a result, the voltage applied to the exciting coil RC and the self-holding resistor RR via the reed switch LS 'is cut off. At the same time, since a voltage is applied to the self-holding resistor RR and the exciting coil RC through the capacitor C 'of the delay means and the resistor R', the exciting coil RC continues to maintain the excited state, and the movable contact The power supply voltage is continuously applied to the motor M through the RS. After a lapse of a predetermined time, the capacitor C 'of the delay means is charged, so that the voltage applied to the exciting coil RC decreases, and finally, the exciting coil RC in the excited state becomes the demagnetized state. Become. As a result, the movable contact RS is turned off, the power supply to the motor M is cut off, and the mirror assembly 3 stops at a predetermined position. On the other hand, when the power supply to the motor M is cut off, the magnetic field of the drive coil LC becomes small or zero, and the reed switch LS 'is turned on.
The voltage charged in the capacitor C 'of the delay means is discharged through the resistor R' of the delay means and the reed switch LS '.

As described above, the third embodiment has the following features.
Since the delay means is provided, the load of the motor M becomes large due to a malfunction due to a rush current of the motor M generated when the power is turned on, and a loss of a mechanical part such as the electronic unit 2 while the mirror assembly 3 is rotating. Malfunction in the event of a failure can be reliably prevented.

In the third embodiment, the resistor R 'of the delay means has a function of discharging the capacitor C' of the delay means and a function of reducing the current discharged from the capacitor C '. . The resistor R 'of the delay means is not always necessary if the contact capacity of the reed switch LS' is sufficient. Further, as the delay means, other than the above-mentioned capacitor C 'and resistor R' may be used.

In the first, second, and third embodiments, the motor for the electric retractable door mirror of the motor vehicle that rotates the mirror assembly from the standing position to the storage position or from the storage position to the standing position. Although the drive control circuit has been described, the motor drive control circuit of the present invention can also be applied to a motor drive control circuit such as a power window motor, a power seat motor, or a power antenna motor.

In the above-described second and third embodiments, the drive coil LC is wound separately and independently of the reed switch LS ', and is disposed close to the reed switch LS'. However, in the present invention, the drive coil LC may be wound outside the reed switch LS '.

[0053]

As is apparent from the above description, the motor drive control circuit of the present invention detects the locked state of the motor by the reed relay, and based on the detection of the reed relay, cuts off the power supply to the motor by the relay circuit. Therefore, the determination of the locked state of the motor has no variation and is clear as compared with the current control by the electronic component.
Therefore, the drive control of the motor can be reliably performed without malfunction.

[Brief description of the drawings]

FIG. 1 is an electric circuit diagram showing a first embodiment of a motor drive control circuit of the present invention.

FIG. 2 is an electric circuit diagram showing a modified example of the first embodiment of the motor drive control circuit of the present invention.

FIG. 3 is an electric circuit diagram showing a second embodiment of the motor drive control circuit of the present invention.

FIG. 4 is an electric circuit diagram showing a third embodiment of the motor drive control circuit of the present invention.

FIG. 5 is a partially broken and partially transparent plan view schematically showing a general electric retractable door mirror.

[Explanation of symbols]

3 ... Mirror assembly (driven body), M ... Motor, L ...
Reed relay, LC: drive coil, LS, LS ': reed switch, Re: relay circuit, RC: excitation coil, R
S: movable contact, RR: self-holding resistor, A1, A2: connector, C: starting capacitor, CN: motor rush current erasing capacitor, R: discharging resistor, PTC: positive characteristic thermistor, C ': delay means , R ': resistance of delay means.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H02P 1/22 B60J 1/17 A

Claims (5)

[Claims] When a motor is energized, the motor is driven to move a driven object, and the driven body reaches a predetermined position and cannot be physically moved, so that the motor is locked. In a motor drive control circuit that sometimes shuts off the current to the motor, the strength of the magnetic field of the drive coil increases due to a lock current generated when the motor is locked, and the reed switch is turned off.
N. A motor drive, comprising: a reed relay that performs N. When a reed switch of the reed relay is turned on, an exciting coil is demagnetized and a movable contact is turned off to cut off the power supply to the motor. Control circuit. 2. When the motor is energized, the motor is driven to move the driven object, and the driven body reaches a predetermined position and cannot be physically moved, so that the motor is locked. In a motor drive control circuit that sometimes shuts off the current to the motor, the strength of the magnetic field of the drive coil increases due to a lock current generated when the motor is locked, and the reed switch is turned off.
A motor drive, comprising: a reed relay that performs FF; and a relay circuit that, when a reed switch of the reed relay is turned off, deactivates an exciting coil to turn off a movable contact and cut off current supply to the motor. Control circuit. 3. The motor according to claim 2, wherein the reed relay is provided with delay means for delaying an excitation state of the excitation coil by a predetermined time after the reed switch is turned off. Drive control circuit. 4. The motor drive control circuit according to claim 3, wherein said delay means is a capacitor connected in parallel with said reed switch. 5. The motor drive control circuit according to claim 3, wherein said delay means comprises a capacitor and a resistor connected in parallel with said reed switch.