JP2010149655A - Door mirror control device - Google Patents

Abstract

A door mirror control device capable of performing stable detection corresponding to a voltage fluctuation range of a DC power supply is provided.
A door mirror control device includes a first control circuit for supplying a drive motor with a current in a direction from a standing position toward a retracted position, and a second current for supplying a current in a direction from the retracted position toward the standing position. The control circuit 2 includes a switch SW1 to drive and control the door mirror, and the first and second control circuits are turned on by the overcurrent detection circuits 5 and 6 that detect the overcurrent flowing through the drive motor and the switching operation. Electronic switch elements Q1 and Q2 for energization to start energization, electronic switch elements Q3 and Q4 for cutoff forcibly turning off the electronic switch element for energization based on the detected voltage, and electronic switch for energization in response to the switching operation The element is changed from off to on and the energizing electronic switch element is changed from on to off with a delay from forced off by the cutoff electronic switch element. And a delay circuit 3,4.
[Selection] Figure 1

Description

  The present invention relates to an improvement in a door mirror control device that drives and controls a vehicle door mirror between a standing position and a retracted position.

  Conventionally, the door mirror control device includes a first control circuit that supplies a current in a direction from the standing position to the retracted position to the drive motor via the power supply line, and a door mirror in the direction from the retracted position to the standing position. And a second control circuit for supplying current to the drive motor via the power supply line, and by switching operation of a changeover switch for switching the connection state of the power supply line to the DC power source, The door mirror is driven and controlled between the direction opposite to the direction (see, for example, Patent Document 1).

  The first control circuit and the second control circuit are an overcurrent detection circuit that detects an overcurrent flowing through the drive motor by converting it into a detection voltage, and is turned on simultaneously with the switching operation to energize the drive motor. And a cutoff electronic switch element for forcibly turning off the conduction electronic switch element based on the detected voltage. In the overcurrent detection circuit, a so-called PTC thermistor whose resistance increases as the temperature rises is used as a shunt resistor.

According to this conventional door mirror control device, when the rotation of the drive motor reaches the storage position from the standing position and is locked, or when the driving motor rotates from the storage position to the standing position and is locked, the lock current (restraint Current) is detected and the current flowing to the drive motor is cut off.
JP 2002-127824 A

  However, in this conventional door mirror control device, when the detection voltage level of the cutoff electronic switch is set corresponding to the high voltage level of the DC power supply, the DC power supply voltage fluctuates and the voltage level of the DC power supply becomes a low voltage level. In this case, even if the door mirror is locked, the lock current flowing through the drive motor is relatively small with respect to the lock current when the DC power supply is at a high voltage, making it difficult to detect the lock current when the DC power supply is at a low voltage. Cause false detection.

  On the other hand, if the detection voltage level of the electronic switch for interruption is set corresponding to the low voltage level of the DC power supply, the door mirror is locked when the DC power supply voltage fluctuates and the DC power supply voltage level becomes high. Since the lock current flowing in the drive motor is relatively large with respect to the lock current when the DC power supply is at a low voltage, the detection of the lock current when the DC power supply is at a high voltage becomes sensitive, which causes false detection.

  In addition, in the case where a PCT thermistor is used as the shunt resistor, since the resistance rapidly increases when the temperature of the PTC thermistor exceeds a predetermined value, the environmental temperature is determined from the predetermined value of the PTC thermistor. The lower it is, the longer it takes for the temperature of the PTC thermistor to reach a predetermined value due to self-heating of the PTC thermistor based on the lock current, and the detection of the current flowing through the drive motor becomes insensitive.

  On the other hand, the closer the environmental temperature is to the predetermined value, the shorter the time until the temperature of the PTC thermistor reaches the predetermined value due to the self-heating of the PTC thermistor based on the lock current, and the overcurrent flowing to the drive motor is reduced. Sensitivity becomes sensitive.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a door mirror control device capable of performing stable detection corresponding to a voltage fluctuation range of a DC power supply.

The door mirror control device according to claim 1, wherein the door mirror is moved from the retracted position to the standing position by supplying a current in a direction from the standing position to the retracted position to the drive motor via the power supply line. A second control circuit for supplying a current in a direction to the drive motor via the power supply line, and a storage position from a standing position by a switching operation of a changeover switch that switches a connection state of the power supply line to a DC power supply. In the door mirror control device that drives and controls the door mirror between the direction toward and the direction opposite to the direction,
The first control circuit and the second control circuit are an overcurrent detection circuit that detects an overcurrent flowing through the drive motor by converting it into a detection voltage, and is turned on by the switching operation to energize the drive motor. An energizing electronic switch element to be started; a shut-off electronic switch element forcibly turning off the energizing electronic switch element based on the detection voltage; and the energizing electronic switch element from off to on in response to the switching operation. And a delay circuit that changes the current-carrying electronic switch element from on to off with a delay to forced-off by the cutoff electronic switch element.

  The door mirror control device according to claim 2, wherein the energizing electronic switch element is a field effect transistor, the blocking electronic switch element is a switching transistor element, and the delay circuit includes a capacitor and a resistance element. The collector of the switching transistor element is connected to the gate of the field effect transistor through the resistance element, and the emitter of the switching transistor element is connected to the source of the field effect transistor through the power supply line. And connected to the voltage application terminal of the drive motor through a diode provided in the middle of the power supply line, and the overcurrent detection circuit is interposed between the voltage application terminal and the drain of the field effect transistor. The shunt resistor is arranged and occurs at both ends of the shunt resistor. A bleeder resistor that divides the voltage, and a capacitor that is provided in parallel with the bleeder resistor and applies a voltage generated at both ends of the bleeder resistor to the base of the switching transistor as the detection voltage, and both ends of the resistor element A diode is connected in parallel to the diode, the anode of the diode is connected to the collector of the switching transistor, and the cathode of the diode is connected to the gate of the field effect transistor.

  According to the present invention, when the power is turned on by operating the changeover switch, the electronic switch element for energization is instantaneously turned on without being delayed through the delay circuit. Regardless of the low voltage level or the high voltage level, the energizing electronic switch element can be reliably turned on.

  On the other hand, when an overcurrent is detected, the energizing electronic switch element is turned off with a predetermined time delay after the shut-off electronic switch element is turned on. Even if it is set according to the voltage level, when overcurrent is detected, the overcurrent detection is delayed and transmitted to the energizing electronic switch element, so that the detection of the lock current at high voltage of the DC power supply becomes sensitive. Can be prevented.

  Embodiments of a door mirror control device according to the present invention will be described below with reference to the drawings.

  FIG. 1 is an explanatory view showing an embodiment of a door mirror control device according to the present invention. In FIG. 1, reference numeral E is a DC power source such as an automobile battery, reference numeral SW1 is a changeover switch, and reference numeral M is a drive. The motor, reference numeral 1 is a first control circuit, and reference numeral 2 is a second control circuit.

  A plus terminal of the DC power source E is connected to the fixed contact X1 and also to the fixed contact X2 via the power supply line L1. The negative terminal of the DC power supply E is connected to the fixed contact X3 and the fixed contact X4 through the power supply line L2.

  The changeover switch SW1 has interlocking segments SWa and SWb, the interlocking segment SWa is connected to the power supply line L3, and the interlocking segment SWb is connected to the power supply line L4. The first control circuit 1 is provided on the power supply line L3 side, and the second control circuit 2 is provided on the power supply line L4 side. The power supply line L3 is connected to the voltage application terminal Ma of the drive motor M through the diode D1, and the power supply line L4 is connected to the voltage application terminal Mb of the drive motor M through the diode D2.

  The first control circuit 1 has a function of rotating the drive motor M in a direction in which a door mirror (not shown) is directed from the standing position toward the storage position, and the second control circuit 2 is configured such that the door mirror is directed from the storage position to the standing position. It has a function of rotating the drive motor M in the direction.

  The changeover switch SW1 has a function of switching the connection state of the power supply lines L3 and L4 to the DC power source E. When the interlocking piece SWa is connected to the fixed contact X1 and the interlocking piece SWb is connected to the fixed contact X4, a positive voltage is applied to the voltage application terminal Ma of the drive motor M and a negative voltage is applied to the voltage application terminal Mb of the drive motor M. Is applied. When the interlocking piece SWa is connected to the fixed contact X3 and the interlocking piece SWb is connected to the fixed contact X2, a negative voltage is applied to the voltage application terminal Ma of the drive motor M and the voltage application terminal Mb of the drive motor M. A + voltage is applied.

  By the switching operation of the selector switch SW1, the voltage polarity of the DC power source E with respect to the drive motor M is switched, and the door mirror is driven and controlled between a direction from the standing position toward the storage position and a direction opposite to this direction.

  The first control circuit 1 and the second control circuit 2 are overcurrent detection circuits 5 and 6 for detecting an overcurrent flowing through the drive motor M by converting it to a detection voltage VK, and an energizing electronic switch element Q1 having a function described later. Q2, switching electronic switching elements Q3 and Q4 having functions to be described later, and switching electronic switching elements Q1 and Q2 from off to on in response to the switching operation and switching electronic switching elements Q3 and Q4 And delay circuits 3 and 4 for changing the current-carrying electronic switch elements Q1 and Q2 from on to off after being forcibly turned off.

  The energizing electronic switch elements Q1 and Q2 have a function of being turned on in response to a switching operation by the changeover switch SW1 and starting energization to the drive motor M. The energizing electronic switch elements Q1 and Q2 have, for example, field effect Type transistor (FET).

  The cutoff electronic switch elements Q3 and Q4 have a function of forcibly turning off the energization electronic switch elements Q1 and Q2 based on the detection voltage of the overcurrent detection circuits 5 and 6, and the cutoff electronic switch elements Q3 and Q4 are For example, it is composed of a switching transistor.

  Delay circuit 3 includes a capacitor C3, a resistance element Rx, and a Zener diode ZD1. Delay circuit 4 includes a capacitor C4, a resistance element Ry, and a Zener diode ZD2.

  One side of the capacitor C3 is connected to the power supply line L3, and the other side is connected to the collector terminal of the cutoff electronic switch element Q3 via the resistance element Rx. The Zener diode ZD1 has its anode terminal connected to the power supply line L3, its cathode terminal connected to the other side of the capacitor C3, and connected to the collector terminal of the shut-off electronic switch element Q3 via the resistor element Rx. . The resistor element Rx is provided with a diode Dx in parallel.

  One side of the capacitor C4 is connected to the power supply line L4, and the other side is connected to the collector terminal of the cutoff electronic switch element Q4 via the resistance element Ry. The Zener diode ZD2 has its anode terminal connected to the power supply line L4, its cathode terminal connected to the other side of the capacitor C4, and connected to the collector terminal of the cutoff electronic switch element Q4 via the resistance element Ry. . The resistor element Ry is provided with a diode Dy in parallel. The cathode of the Zener diode ZD1 is connected to one side of the common resistor R5 via the resistor element Rx. The cathode of the Zener diode ZD2 is connected to the other side of the common resistor R5 via the resistor element Ry.

  The source of the energizing electronic switch element Q1 is connected to the power supply line L3. The drain of the energizing electronic switch element Q1 is connected to the voltage application terminal Ma of the drive motor M via the shunt resistor R01. The source of the energizing electronic switch element Q2 is connected to the power supply line L4. The drain of the energizing electronic switch element Q2 is connected to the voltage application terminal Mb of the drive motor M via the shunt resistor R02.

  The emitter of the cutoff electronic switch element Q3 is connected to the power supply line L3, and the collector of the cutoff electronic switch element Q3 is connected to the gate of the energizing electronic switch element Q1 via the resistance element Rx. The emitter of the blocking electronic switch element Q4 is connected to the power supply line L4, and the collector of the blocking electronic switch element Q4 is connected to the gate of the energizing electronic switch element Q2 via the resistance element Ry.

  The overcurrent detection circuit 5 includes a shunt resistor R01, a first voltage dividing resistor element R1, a second voltage dividing resistor element R3 as a bleeder resistor, and a capacitor C1. The shunt resistor R01 is disposed between the voltage application terminal Ma of the drive motor M and the drain of the energizing electronic switch element Q1. The overcurrent detection circuit 6 includes a shunt resistor R02, a first voltage dividing resistor element R2, a second voltage dividing resistor element R4 as a bleeder resistor, and a capacitor C2. The shunt resistor R02 is disposed between the voltage application terminal Mb of the drive motor M and the drain of the energizing electronic switch element Q2.

  One side of the first voltage dividing resistor element R1 is connected to the voltage application terminal Ma of the drive motor M, the other side of the first voltage dividing resistor element R1 is connected to the base of the blocking electronic switch element Q3, and the second The voltage dividing resistor element R3 is connected to one side. The other side of the second voltage dividing resistor R3 is connected to the power supply line L3. Capacitors C1 are connected in parallel to both sides of the second voltage dividing resistor element R3.

  One side of the first voltage dividing resistor element R2 is connected to the voltage application terminal Mb of the drive motor M, the other side of the first voltage dividing resistor element R2 is connected to the base of the blocking electronic switch element Q4, and the second The voltage dividing resistor element R4 is connected to one side. The other side of the second voltage dividing resistor R4 is connected to the power supply line L4. A capacitor C2 is connected in parallel on both sides of the second voltage dividing resistor element R4.

  According to the embodiment of the present invention, when the changeover switch SW1 is operated to connect the interlocking segments SWa and SWb to the fixed contacts X1 and X4, the charging current from the DC power source E is indicated by arrows a1 to a3, the connection point S1, and the arrow a4. , A5 through the capacitor C4, the gate voltage of the energizing electronic switch element Q2 increases instantaneously, and the energizing electronic switch element Q2 is immediately turned on.

  As a result, the direction of the arrow Y1 from the positive side of the DC power supply E via the fixed contact X1, the interlocking piece SWa, the diode D1, the drive motor M, the shunt resistor R02, the energizing electronic switch element Q2, the interlocking piece SWb, and the fixed contact X4. Current flows toward the negative side of the DC power supply E, for example, the door mirror is driven from the retracted position toward the standing position.

  Next, when the door mirror reaches the standing position, the rotation of the drive motor M is forcibly stopped. However, since a current continues to flow through the drive motor M as a lock current (restraint current), it occurs at both ends of the shunt resistor R02. The voltage V increases.

  When the voltage dividing resistance value by the first voltage dividing resistor element R2 and the second voltage dividing resistor element R4 exceeds the detection voltage VK, the cutoff electronic switch Q4 is turned on from off, but the capacitor C4 constituting the delay circuit 4 And the resistance element Ry cause a discharge current to flow through the arrow b1, the connection point S1, and the emitter of the cutoff electronic switch element Q4.

  Therefore, the gate voltage of the energizing electronic switch element Q2 decreases with a delay from the change of the cutoff electronic switch Q4 from OFF to ON. That is, the energizing electronic switch element Q2 is turned off with a delay from the turning-off electronic switch Q4 changing from OFF to ON.

  Next, when the changeover switch SW1 is operated to connect the interlocking segments SWa and SWb to the fixed contacts X3 and X2, the charging current flows to the capacitor C3 via the connection point S2 and the arrow C1, and the energizing electronic switch element Q1. Immediately increases, and the energizing electronic switch element Q1 is immediately turned on.

  As a result, the direction of the arrow Y2 from the positive side of the DC power supply E via the fixed contact X2, the interlocking piece SWb, the diode D2, the drive motor M, the shunt resistor R01, the energizing electronic switch element Q1, the interlocking piece SWa, and the fixed contact X3. Current flows toward the negative side of the DC power source E, for example, the door mirror is driven from the standing position toward the retracted position.

  Next, when the door mirror reaches the retracted position, the rotation of the drive motor M is forcibly stopped. However, since the current continues to flow as a lock current (restraint current) in the drive motor M, it occurs at both ends of the shunt resistor R01. The voltage V increases.

  When the voltage dividing resistance value of the first voltage dividing resistor element R1 and the second voltage dividing resistor element R3 exceeds the detection voltage VK, the cutoff electronic switch element Q3 is turned on from off, but the capacitor constituting the delay circuit 3 A discharge current caused by C3 and the resistance element Rx flows through the arrow d1, the connection point S2, and the emitter of the cutoff electronic switch element Q3.

  Accordingly, the gate voltage of the energizing electronic switch element Q1 decreases with a delay from the change of the cutoff electronic switch Q3 from OFF to ON. That is, the energizing electronic switch element Q1 is turned off with a delay from the change of the cutoff electronic switch Q3 from OFF to ON.

  Since the delay circuits 3 and 4 are set to have a longer discharge time than the charge time, the energizing electronic switch elements Q1 and Q2 are turned on before the cutoff electronic switch elements Q3 and Q4 are turned on.

  According to this embodiment, when the selector switch SW1 is operated to turn on the power, the energizing electronic switch elements Q1 and Q2 are instantaneously turned on without being delayed through the delay circuits 3 and 4. Therefore, regardless of whether the overcurrent detection level is set to a low voltage level or a high voltage level, the energizing electronic switch elements Q1 and Q2 can be reliably turned on when the power is turned on.

  On the other hand, when an overcurrent is detected, the cutoff electronic switch elements Q3 and Q4 are turned on, and after a predetermined time, the energization electronic switch elements Q1 and Q2 are turned off. Therefore, even if the detection voltage level of the cutoff electronic switches Q3 and Q4 is set corresponding to the low voltage level of the DC power supply E, the overcurrent detection is delayed at the time of overcurrent detection, and the energization electronic switch elements Q1 and Q2 are delayed. Therefore, it is possible to prevent the detection of the lock current when the DC power source E is at a high voltage from becoming sensitive.

  Although the embodiment has been described above, as shown in FIG. 2, PTC thermistors PCT1 and PCT2 whose resistance values increase as the temperature rises can be used as the shunt resistors R01 and R02.

It is a circuit diagram of the door mirror control device concerning the present invention. It is a circuit diagram which shows the modification of the door mirror control apparatus shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... 1st control circuit 2 ... 2nd control circuit 3, 4 ... Delay circuit 5, 6 ... Overcurrent detection circuit E ... DC power supply M ... Drive motor SW1 ... Changeover switch Q1, Q2 ... Electronic switch element Q3, Q4 for electricity supply ... Electronic switch element for interruption

Claims (2)

A first control circuit for supplying a current in a direction from the standing position toward the retracted position to the drive motor via a power supply line; and a current in a direction in which the door mirror is directed from the retracted position to the standing position via the power supply line. And a second control circuit for supplying to the drive motor, and by a switching operation of a changeover switch for switching a connection state of the power supply line to a DC power source, a direction from the standing position to the storage position and a direction opposite to the direction In the door mirror control device for driving and controlling the door mirror between,
The first control circuit and the second control circuit are an overcurrent detection circuit that detects an overcurrent flowing through the drive motor by converting it into a detection voltage, and is turned on by the switching operation to energize the drive motor. An energizing electronic switch element to be started; a shut-off electronic switch element forcibly turning off the energizing electronic switch element based on the detection voltage; and the energizing electronic switch element from off to on in response to the switching operation. And a delay circuit that changes the current-carrying electronic switch element from on to off with a delay to forced-off by the shut-off electronic switch element.   The energizing electronic switch element is a field effect transistor, the blocking electronic switch element is a switching transistor element, the delay circuit includes a capacitor and a resistor element, and the collector of the switching transistor element is the resistor And an emitter of the switching transistor element is connected to the source of the field effect transistor via the power supply line and provided in the middle of the power supply line. The overcurrent detection circuit is connected to a voltage application terminal of the drive motor via a diode, and a shunt resistor disposed between the voltage application terminal and the drain of the field effect transistor, and the shunt resistor A bleeder resistor for dividing the voltage generated at both ends; A capacitor that is provided in parallel with the resistor and applies a voltage generated at both ends of the bleeder resistor to the base of the switching transistor as the detection voltage, and a diode is connected in parallel to both ends of the resistance element, 2. The door mirror control device according to claim 1, wherein an anode of the diode is connected to a collector of the switching transistor, and a cathode of the diode is connected to a gate of the field effect transistor.

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