JP2001328487A - Control device for motor-driven housed type door mirror - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a control device for a motor-driven housed type door mirror capable of individually setting driving masking time and detecting masking time. SOLUTION: When a change-over switch SW1 is operated to apply forward voltage to a driving motor M1, a stabilized DC voltage V1 is outputted from a stabilizing power circuit 2. A switching means 4 is thereby put in an ON state to rotate the driving motor M1 in a forward direction, and the ON state is continued until the lapse of starting masking time set by a driving masking time setting circuit 7. Then in the case the rotation of the door mirror is locked and the rotation of the driving motor M1 is forcibly impeded, a locking current flowing at this time is detected by a detecting resistance, and the circuit is cut off after the lapse of detecting masking time. With this constitution, the starting masking time and detecting masking time can be individually set, so that the occurrence of malfunction can be prevented, and a burden on mechanical parts can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for controlling the operation of standing up and retracting an electrically retractable door mirror,
The present invention relates to a technique capable of reliably stopping a door mirror at a predetermined standing position and a storage position without imposing a load on mechanical parts.

[0002]

2. Description of the Related Art In general, a door mirror mounted on a vehicle and projected on a side portion of the vehicle for the purpose of visually observing a rear side is often obstructed when passing through a narrow road or entering a garage. In addition, an electric retractable door mirror having a function of switching a standing position (a position at the time of normal use) or a storage position (a folded position) by rotating a door mirror by a remote control operation is often used.

Further, in such an electric retractable door mirror, it is desired to control a rotation drive motor so that the rotation of the door mirror stops accurately at a predetermined standing position or a retracted position. When rotating to reach the standing position or the storage position, the rotation is forcibly stopped by mechanically locking, and the overcurrent flowing at this time is detected, and the rotation to the rotation driving motor is detected. The energization is stopped.

[0004] As a conventional control device for an electric retractable door mirror, for example, one disclosed in Japanese Patent Application Laid-Open No. 10-35362 (hereinafter referred to as a conventional example) is known. FIG. 7 is an explanatory diagram showing the configuration of the control circuit shown in the conventional example. As shown in FIG.
Is operated by operating the changeover switch SW10.
By rotating the drive motor M10 forward or backward, the door mirror (not shown) can be rotated to the storage position or the upright position.

[0005] Further, the drive motor M10 is rotated forward to rotate the door mirror toward the storage position, and when the door mirror reaches a predetermined storage position, the door mirror is locked and the rotation is forcibly stopped. Therefore, the driving motor M1
An overcurrent (hereinafter referred to as a lock current) flows through 0. As a result, the voltage across the overcurrent detection resistor R20 increases, so that the FE that operates as a switching element
T21 is shut off, and the supply of the power supply voltage to the driving motor M10 is stopped.

When the power supply voltage is applied to the drive motor M10 by operating the changeover switch SW10, an inrush current (transient current) which instantaneously reaches several times the steady-state current flows. Therefore, this inrush current is detected and FET
A predetermined time after power-on (this is referred to as a mask time) is set so that the FET 21 is kept on irrespective of the occurrence of overcurrent so that the power supply 21 is not interrupted. In the case of FIG. 7, it is determined by the magnitude of the collector current flowing through the capacitor C10 and the transistors Q10 and Q11.

The mask time occurs not only when the power is turned on but also when the power is turned off. That is, when the driving motor M10 is forcibly stopped and a lock current resulting therefrom flows, the current detection resistor R20 detects this overcurrent and does not immediately cut off the FET 21 but instead keeps a constant value. After the masking time. This can solve the problem that the drive motor M10 malfunctions in response to sudden noise.

FIG. 8 is a characteristic diagram showing a change in the current flowing through the drive motor M10 from the supply of the voltage to the drive motor M10 to the stop thereof. Flow, during which a steady current flows. The time indicated by t10 and t11 is the mask time.

However, in the above-described conventional control device, the mask time t10 set when the driving motor M10 starts rotating and the mask time t11 when the lock current is detected are necessarily set to the same time. If the mask time is set to be long, even after the door mirror reaches the retracted position or the upright position, the rotational force is further continued to be applied, so that a large load is imposed on the mechanical parts.

When the door mirror rotates with high torque and reaches the retracted position or the upright position and stops,
In this position, the switch may be firmly tightened.
Even if W10 is operated, the driving motor M10 does not rotate,
Troubles that cause malfunctions occur. For example, when the battery voltage is high, such as after running the vehicle at high speed, the door mirror rotates with a high torque to reach the storage position, or the upright position, and thereafter, when the temperature is low in the early morning, etc. When reversing the door mirror when the battery voltage is low, since the rotation torque is small,
There is a problem that the door mirror cannot be rotated.

Further, if the mask time is set short in order to solve the above-mentioned problem, a problem arises in which a rush current flowing when the power is turned on is detected and the circuit is cut off.

On the other hand, the voltage of a battery mounted on a vehicle fluctuates greatly due to running conditions and the surrounding environment.
Therefore, the current (steady-state current and lock current) flowing through the driving motor M10 driven by using this battery as a power supply is
When the battery voltage is high, the steady current and the lock current are both increased when the battery voltage is high. Conversely, when the battery voltage is low, both the steady current and the lock current are low.

FIG. 9 shows the relationship between the battery voltage and the driving motor M1.
FIG. 6 is a characteristic diagram showing a relationship with a current flowing to 0 (reference numeral S1 is a steady current, reference numeral S2 is a lock current). When the battery voltage increases, the current flowing to the drive motor M10 changes so as to increase.

The current detecting resistor R2 shown in FIG.
Since the lock current value detected at 0 is not always constant but fluctuates due to ambient conditions and the like, for example, as shown in FIG. The level fluctuates in the range of currents Ia-1 to Ia-2.

Therefore, as shown at point P101 in FIG.
When the battery voltage is low and the current detection level is increasing, at a battery voltage lower than this, although the lock current is flowing through the drive motor M10, this is not detected, and the drive current is not detected. A trouble that voltage is continuously applied to the motor M10 occurs.

As shown at point P102 in FIG. 9, when the battery voltage is high and the current detection level is falling, a steady current is supplied to the driving motor M10 at a battery voltage higher than this. In spite of flowing (unlocked), this current is detected as a lock current, and a malfunction of shutting down the circuit occurs.

Furthermore, when the battery voltage rises, the lock current also rises with this, and the door mirror rotates with high torque, so that there is a problem that a large load is imposed on mechanical parts during locking.

As shown in FIG. 10, the current flowing through the drive motor M10 (the steady current S3 and the lock current
4) also varies depending on the ambient temperature. The current increases when the ambient temperature is low, and decreases when the ambient temperature is high. Therefore, when the ambient temperature rises and the current detection level rises to the point P103 or higher, it is not possible to detect the occurrence of lock even though the drive motor M10 is locked. Conversely, when the ambient temperature decreases and the current detection level decreases, the point P10
If the value is less than 4, a problem occurs in that the lock current is detected despite the steady current flowing through the drive motor M10.

[0019]

As described above, in the conventional electric retractable door mirror control device,
There were the following issues. (A) The mask time at the start of the rotation of the door mirror is the same as the mask time after the door mirror reaches the predetermined storage position or the upright position and the lock current is detected by the drive motor M10. If you set a longer time,
When a strong force is applied during locking, a large load is imposed on mechanical parts. Conversely, when the mask time is set short, an inrush current at the start of rotation is detected and the drive motor M1 is detected.
A trouble occurs that the rotation of 0 stops.

(B) Since the detected value of the lock current is not constant at all times, despite the steady-state current flowing due to fluctuations in the battery voltage of the vehicle and changes in the ambient temperature,
A trouble occurs in which the generation of the lock current is detected, and the lock current is not detected despite the flow of the lock current.

(C) When the battery voltage rises, the lock current increases and the rotational torque of the door mirror increases, so that excessive force acts on the mechanical parts when the door mirror is locked, damaging the mechanical parts. There are drawbacks.

The present invention has been made to solve such a conventional problem. It is an object of the present invention to separately set a mask time at the time of starting and a mask time at the time of stopping rotation. A drive control apparatus for an electric retractable door mirror capable of reliably detecting a lock current and stopping rotation of a drive motor even when a battery voltage fluctuation or an ambient temperature change occurs. is there.

[0023]

In order to achieve the above object, the invention described in claim 1 of the present application has a function of rotating a door mirror mounted on a vehicle to a storage position or an upright position by electric operation. In a control device for controlling the rotation drive of the electric retractable door mirror, a drive motor for rotating the door mirror to the storage position or the upright position, and switching the polarity of a DC power supply mounted on the vehicle,
A changeover switch that supplies a power supply voltage to the drive motor, the changeover switch, a switching unit that is provided between the drive motor and switches on and off the drive motor, the changeover switch, A current detection unit installed between the drive motor and a lock current flowing through the drive motor; and a current detection unit installed on the drive motor side of the changeover switch;
A stabilized power supply circuit that outputs a voltage of the same polarity irrespective of the connection polarity of the changeover switch; and a drive circuit that is driven by the output voltage of the stabilized power supply circuit. And a switching control means for controlling the switching means to be cut off with a masking time at the time of detection when a lock current is detected by the current detection means.

According to a second aspect of the present invention, there is provided a control for controlling the rotational drive of an electrically retractable door mirror having a function of rotating a door mirror mounted on a vehicle to a retracted position or an upright position by electric operation. In the device, a first connection terminal, and a second connection terminal, the drive motor for rotating the door mirror to the storage position or the upright position, and the polarity of the DC power supply mounted on the vehicle is switched, A switch for supplying a forward voltage or a reverse voltage to the drive motor; and a switch for turning the drive motor on between the switch and a first connection terminal of the drive motor. , A first switching means for switching off, a first current detection means for detecting that a lock current has flowed in the driving motor, and the first switching means for applying a forward voltage. And a first rectifying element for applying a forward voltage to the drive motor by bypassing the switching means and the first current detection means, wherein the changeover switch and a second rectifier of the drive motor are provided. A second switching means for switching the drive motor on and off, a second current detection means for detecting that a lock current has flowed through the drive motor, and a reverse direction between the connection terminal and the connection terminal. A second rectifying element for applying a reverse voltage to the drive motor while bypassing the second switching means and the second current detecting means at the time of applying a voltage, and further comprising: A stabilized power supply circuit which is installed on the driving motor side and always outputs a voltage of the same polarity regardless of the connection polarity of the changeover switch; At the time of voltage application, the second switching means is turned on with a startup mask time, and when a lock current is detected by the second current detection means, the second switching means is held with a detection mask time. Control to shut off the switching means,
In addition, when the reverse voltage is applied, the first switching means is turned on with a start-up mask time, and when the lock current is detected by the first current detection means, the detection-time mask time is set. Switching control means for controlling to cut off the first switching means.

According to a third aspect of the present invention, the switching control means includes a start-up mask time setting circuit for continuously outputting a turn-on detection signal for the start-up mask time from power-on. Is output, forcibly turning on at least one of the first switching means and the second switching means.

According to a fourth aspect of the present invention, the switching control means outputs a lock current detection signal after the detection time mask time has elapsed after the first current detection means detects the occurrence of the lock current. A second detection-time mask time setting circuit, and a second detection-time mask time setting circuit that outputs a lock current detection signal after the detection time mask time elapses after the occurrence of the lock current is detected by the second current detection means. And a lock current detection signal output from the first and second detection-time mask time setting circuits.
And turning off the second switching means.

According to a fifth aspect of the present invention, the switching control means includes a reference voltage generating circuit that outputs an output voltage of the stabilized power supply circuit or a voltage obtained by dividing the output voltage as a reference voltage. A start-up mask time setting circuit for continuously outputting a turn-on detection signal for the start-up mask time from power-on, and a detection-time mask time elapse after a lock current is detected by the first current detection means. A first detection mask time setting circuit for outputting a lock current detection signal later, a lock current detection signal output from the first detection mask time setting circuit, and a reference voltage output from the reference voltage generation circuit And a first comparing means for comparing the input signal and an input detection signal output from the start-time mask time setting circuit, and are turned on, and the output signal of the first comparing circuit is applied. A first switching means for supplying an output signal which is turned off when the lock current is supplied to the first switching means, and a detection time mask time lapse after a lock current is detected by the second current detection means. A second detection mask time setting circuit for outputting a lock current detection signal later, a lock current detection signal output from the second detection mask time setting circuit, and a reference voltage output from the reference voltage generation circuit And a second comparing means for comparing the input signal with the ON-state detection signal output from the start-up mask time setting circuit, and turning on when the output signal of the second comparison circuit is supplied. And second switching means for supplying an output signal to be turned off to the second switching means.

According to a sixth aspect of the present invention, at least one of the first switching means and the second switching means limits a current flowing through the driving motor to a predetermined threshold value or less. A switching element having a function is provided.

The invention according to claim 7 is characterized in that the output voltage of the stabilized power supply circuit is increased or decreased in accordance with the increase or decrease of the output voltage of the DC power supply. An eighth aspect of the present invention is characterized in that the output of the stabilized power supply circuit decreases as the ambient temperature increases, and changes as the ambient temperature decreases.

According to the present invention having the above-described structure, when the changeover switch is operated to apply a DC voltage to the drive motor in the forward or reverse direction, when the DC voltage is applied, the startup mask time is reduced. The switching means is turned on. As a result, until the startup mask time elapses, even if an overcurrent occurs, it is possible to avoid the trouble of detecting the overcurrent and interrupting the circuit. Further, a detection time mask time setting circuit is provided, and the time required from the detection of the lock current of the driving motor to the actual cutoff of the circuit is defined as the detection time mask time, and the start time mask time described above. Can be set separately.

As a result, it is possible to prevent a malfunction due to an inrush current generated at the time of turning on the power by setting a long mask time at the time of driving, and to set a short mask time at the time of detection, so that after the lock current detection, In addition, the force unnecessarily applied to the mechanical parts can be reduced.

Further, the DC voltage output from the stabilized power supply circuit increases or decreases as the battery voltage increases or decreases or as the ambient temperature fluctuates. Therefore, the lock current detection level set based on this DC voltage changes. I do. Therefore, even if a change in the battery voltage or a change in the ambient temperature occurs, the occurrence of the lock current can be reliably detected.

[0033]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing a configuration of a control device for an electric retractable door mirror according to the present invention, and FIG.
This specific circuit diagram is shown.

As shown in the figure, the control device 1 is connected to a battery (DC power supply) E1 mounted on a vehicle, and is connected to a changeover switch SW1 for switching the polarity and outputting a signal, and to a rear stage of the changeover switch SW1. A stabilizing power supply circuit 2 which always outputs a DC voltage of the same polarity regardless of the connection state of the changeover switch SW1, and a rearwardly arranged side mirror (not shown) which is arranged at the subsequent stage of the changeover switch SW1. A drive motor M1 for moving the door mirror to a standing position or a storage position.

Further, a connection terminal T1 of the driving motor M1 is provided.
A current detecting resistor R3 (current detecting means) and a switching means 3 are disposed between the switch R1 and the switch SW1, and a diode D4 ( Rectifier) is installed. Similarly, the connection terminal T of the drive motor M1
2 and a changeover switch SW1, a current detecting resistor R4 (current detecting means) and a switching means 4 are arranged, and a diode D5 is connected to bypass the series connection of the resistor R4 and the switching means 4. (Rectifier element) is installed.

When starting rotation of the drive motor M1, a start-up mask time setting circuit 7 for setting a time for continuously applying a voltage to the drive motor M1 (start-up mask time); Detection mask time setting circuit 8 for setting the time (detection mask time) required from when the lock current is detected to flow through the motor M1 to when the supply of the voltage to the drive motor M1 is actually cut off. , 9
And a reference voltage generating circuit 10, comparator circuits (comparing means) 11 and 12, and flip-flop circuits (switching means) 13 and 14.

The changeover switch SW1 has the contacts x1, y
1, z1 and a switch unit having contacts x2, y2, and z2. When the contacts x1 and z1 and the contacts x2 and z2 are connected, respectively, a driving motor M1 is connected. , A reverse voltage is applied to the drive motor M1 when the contacts y1 and z1 and the contacts y2 and z2 are respectively connected. Note that a PTC element 5 for current limitation is provided at a stage subsequent to the contact z1.

The stabilized power supply circuit 2 has four diodes D
1-1, D1-2, D2-1, D2-2, a diode bridge circuit 6, a resistor R1, a Zener diode ZD1 for stabilizing the output voltage, and a capacitor for smoothing the output voltage C1 and a resistor R2. Then, a stabilized DC voltage V1 is output.

The start-up mask time setting circuit 7 includes a resistor R1
3 and a diode D3 connected in parallel to the resistor R13. A stabilized power supply circuit is provided at both ends of the series connection circuit of the resistor R13 and the capacitor C4. 2 is applied. The connection point (P1) between the resistor R13 and the capacitor C4 is connected to the flip-flop circuit 1
3, 14 are connected.

The detection mask time setting circuit 8 includes a resistor R5
And a series connection circuit of R6 and an end of the resistor R5.
A DC voltage V1 is applied between the resistor R3 and the switching means 3, and an end of the resistor R6 is applied. Further, the resistors R5 and R6 have an extremely large resistance value as compared with the resistor R3. Further, a connection point between the resistors R5 and R6 is connected to a series connection circuit of the resistor R11 and the capacitor C2, and a connection point between the resistor R11 and the capacitor C2 is connected to the comparator circuit 11.

Similarly, the detection mask time setting circuit 9 includes a series connection circuit of resistors R9 and R10.
Is connected between the resistor R4 and the switching means 4, and a DC voltage V1 is applied to an end of the resistor R9. The resistances of the resistors R9 and R10 are extremely large as compared with the resistance R4. Further, a series connection circuit of a resistor R12 and a capacitor C3 is connected to a connection point (P2) between the resistors R9 and R10.
3 is connected to the comparator circuit 12.

The reference voltage generating circuit 10 includes resistors R7 and R8
, And outputs a voltage obtained by dividing the DC voltage V1 output from the stabilized power supply circuit 2 at a ratio of two resistors R7 and R8 to the comparator circuits 11 and 12 as a reference voltage. The voltage dividing ratio between the resistors R7 and R8 is larger than the voltage dividing ratio between the resistors R6 and R5 (or the voltage dividing ratio between the resistors R9 and R10). That is, (R7 / R
8)> (R6 / R5).

The comparator circuit 11 includes an amplifier A1, a capacitor C5, and a resistor R14. The comparator circuit 11 outputs a voltage (lock current detection signal) output from the detection mask time setting circuit 8 and an output from the reference voltage generation circuit 10. Compare with reference voltage. If the reference voltage is higher, an "H" level signal is output. Conversely, if the voltage output from the detection time masking section 8 is higher, an "L" level signal is output. Output.

The comparator circuit 12 includes an amplifier A2 and a resistor R15. The comparator circuit 12 includes a voltage (lock current detection signal) output from the detection mask time setting circuit 9 and a reference voltage output from the reference voltage generation circuit 10. Compare. If the reference voltage is higher, an "H" level signal is output. If the voltage output from the detection time masking section 9 is higher, an "L" level signal is output.

In the flip-flop circuit 13, when both the set input "S" and the reset input "R" are at "H" level (that is, both "S bar" and "R bar" are "L").
Level), the output “Q” operates so as to be at the “H” level. The “S bar” input is connected to the output end of the start-up mask time setting unit 7 and the “R bar” Is connected to the output terminal of the comparator circuit 11. Further, a capacitor C6 is provided.

Similarly to the flip-flop 13, when the set input “S” and the reset input “R” are both at the “H” level, the output “Q” is at the “H” level. It works to become.
The “S bar” input includes a start-up mask time setting unit 7.
The output terminal of the comparator circuit 12 is connected to the “R bar” input.

The switching means 3 comprises an FET 15 and resistors R16 and R18, and supplies a voltage obtained by dividing the "Q" output of the flip-flop circuit 13 by the two resistors R16 and R18 to the gate of the FET 15. .

The switching means 4 comprises an FET 16 and resistors R17 and R19, and supplies a voltage obtained by dividing the "Q" output of the flip-flop circuit 14 by the two resistors R17 and R19 to the gate of the FET 16. . Also,
A noise removing element Z1 is arranged between both ends (T1, T2) of the driving motor M1.

Next, the operation of the present embodiment configured as described above will be described. Here, as an example of the operation,
The operation when the door mirror is in the upright position, a forward voltage is applied to the drive motor M1, the door mirror is rotated in the forward direction, and the door mirror is moved to the storage position will be described.

When the operator operates the changeover switch SW1 to switch between the contacts x1 and z1 and the contacts x2 and z2, the voltage output from the battery E1 becomes
The power is supplied to the stabilized power supply circuit 2. The stabilized power supply circuit 2 stabilizes and smoothes the supplied voltage to convert the DC voltage V1
Is output.

Since this DC voltage V1 is applied to the start-up mask time setting section 7, the start-up mask time setting section 7
The voltage at the connection point P1 between the resistor R13 and the capacitor C4 gradually increases with time. That is, when the change-over switch SW1 is turned on, an “L” level signal (a turn-on detection signal) is output, and this signal reaches the “H” level after the elapse of the start-up mask time (referred to as t1).

Therefore, "S" of the flip-flop circuit 14
The "bar" input is supplied with an "L" level signal and is connected at time t1.
After the elapse, the signal is switched to the “H” level signal. At this time,
Since the reference voltage output from the reference voltage generation circuit 10 is higher than the voltage output from the mask time setting unit 9 at the time of detection, the output voltage of the comparator circuit 12 is at the “H” level, and therefore, the flip-flop circuit An “H” level signal is input to 14 “R bar”.

Therefore, the "Q" output of the flip-flop circuit 14 is switched from the power-on (the changeover switch SW1).
Is switched to “H” level until the time t1 elapses, and thereafter, a signal holding this output is output. By this output, F of the switching means 4
ET16 is turned on, and a forward current flows through the driving motor M1. That is, the contact x1, the contact z1, the PTC element 5,
Since current flows in a loop through the path of the diode D4, the drive motor M1, the FET 16, the current detection resistor R4, the contact z2, and the contact x2, the drive motor M1 starts rotating in the forward direction.

At this time, the "Q" output is maintained at "H" level irrespective of the "R bar" input of the flip-flop circuit 14 until the time t1 (mask time at start-up) elapses from the power-on. Therefore, it is possible to prevent a malfunction in which the inrush current at the time of turning on the power is detected and the rotation of the driving motor M1 is stopped.

Thereafter, when the door mirror reaches a predetermined storage position and the rotation of the driving motor M1 is forcibly stopped, a lock current flows through the driving motor M1. As a result, the voltage generated across the resistor R4 increases,
The voltage at the connection point P2 between the resistors R9 and R10 of the detection mask time setting circuit 9 rises, and the resistor R12 and the capacitor C3
The voltage value at the connection point P3 gradually increases with a time constant determined by the resistance value of the resistor R12 and the capacitance of the capacitor C3.

After a lapse of a predetermined time (this is referred to as a detection-time mask time t2), the voltage at the point P3 exceeds the reference voltage output from the reference voltage generation circuit 10, and the output of the comparator circuit 12 is inverted. . That is, the output of the comparator circuit 12 is switched from the “H” level to the “L” level after a lapse of time t2 since the detection of the lock current. Therefore, the "R" input of the flip-flop circuit 14 is switched from the "H" level to the "L" level.

As a result, the "Q" output of the flip-flop circuit 14 is set to the "L" level, so that the FET 16
Is turned off, and the voltage supply to the driving motor M1 is stopped. This state is maintained until the changeover switch SW1 is operated next time.

On the other hand, the changeover switch SW1 is set to the contact y
1, when connected to the z1 side and the contacts y2, z2 side, only the rotation direction of the drive motor M1 changes, and otherwise operates in the same procedure as described above. That is, the detection mask time setting circuit 8, the comparator circuit 11, the flip-flop circuit 13, and the switching means 3 operate to rotate the driving motor M1 in the reverse direction and move the door mirror from the storage position to the standing position. Can be done.

In the above-described embodiment, the start-up mask time t1 can be set by the time constant determined by the resistor R13 and the capacitor C4 constituting the start-up mask time setting circuit 7. The time constant determined by the resistor R12 and the capacitor C3 forming the time setting circuit 9 and the time constant determined by the resistor R11 and the capacitor C2 forming the masking time setting circuit 8 in the detection time, Since t2 can be set, the start-up mask time t1 and the detection-time mask time t2 can be set separately.

Accordingly, by setting the start-up mask time t1 to be long, it is possible to prevent malfunction due to an inrush current when the power is turned on. Further, by setting the detection mask time t2 to be short, the time during which the current continues to flow after the door mirror is locked can be shortened, so that it is possible to avoid the trouble of continuously applying excessive force to mechanical parts. it can. This will be described in more detail with reference to FIG.

FIG. 3 is an explanatory diagram showing a state of a change in a current value after a power supply voltage is applied to the driving motor M1 until the locking current flows to the driving motor M1 and the motor stops. As shown, immediately after the application of the power supply voltage, an inrush current i1 that is several times the steady-state current flows. However, the time during which the inrush current i1 is equal to or higher than the current detection level Ia is shorter than the start-up mask time t1, so that the generation of the inrush current does not interrupt the circuit. Also,
The driving motor M1 is forcibly stopped, and the lock current i2
Flows, the circuit is interrupted after the detection mask time t2 has elapsed since the detection of the flow of the lock current. Since the mask time t2 at the time of detection is set to a time shorter than the mask time t1 at the time of activation, an excessive force is not continuously applied to the mechanical parts.

Further, even when the noise current i3 is generated while the driving motor M1 is rotating, the generation time of the noise current i3 is shorter than the mask time t2 at the time of detection, so that a malfunction due to the influence of noise is caused. Can be prevented from occurring.

As described above, in the electric retractable door mirror control device according to the present embodiment, the start-up mask time t1
And the detection-time mask time t2 can be set separately, so that malfunction can be prevented, and the load on the mechanical parts can be reduced. Therefore, even when the door mirror is in the retracted state when the battery voltage is high, such as after high-speed running, and when the door mirror is in the upright state when the battery voltage is low, such as early in the morning when the temperature is low, the door mirror can be reliably rotated. .

The gate voltages of the FETs 15 and 16 are
(Gate cutoff voltage)-(limit current) × (resistance R
3, the resistance value of the resistor R4), when the current flowing through the driving motor M1 reaches the limit current, the FET1
Since the gate voltages of the FETs 5 and 16 become smaller than the cutoff voltage, the FETs 15 and 16 operate in a direction in which they are turned off.
Then, the current flowing through the driving motor M1 decreases,
Since the gate voltage increases again, the operation is performed so that the motor current increases. Then, by repeating this operation, the lock current of the driving motor M1 can be suppressed to the limited current or less.

As a result, normally, as shown in FIG. 4A, the lock current rises as the battery voltage rises, but as shown in FIG. When the lock current reaches a predetermined limit current, further increase can be suppressed.
Therefore, the rotational torque of the driving motor M1 can be suppressed, and the application of unnecessary force to the mechanical parts can be prevented.

When the voltage of the battery E1 increases,
Diode D1-2 Constituting Diode Bridge Circuit 6
Since the current flowing through (D1-1) increases and the Zener voltage (the voltage across Zener diode ZD1) increases, the DC voltage V1 generated in the stabilized power supply circuit 2 increases. Accordingly, the reference voltage (the voltage obtained by dividing the DC voltage V1 by the resistors R7 and R8) output from the reference voltage generation circuit 10 also increases.

Therefore, as shown in FIG.
The current detection level Ia changes in accordance with the voltage fluctuation of. As a result, according to the voltage fluctuation of the battery E1,
Even when the normal current and the lock current flowing through the drive motor M1 rise and fall, the current detection level Ia rises and falls with this, so that the current detection level Ia
When the current fluctuates in the range of Ia-1 to Ia-2, the normal current is erroneously detected as the lock current, or even though the lock current is flowing, the current is not detected. The problem of continuing can be avoided.

Similarly, as shown in FIG. 6, even when the normal current and the lock current fluctuate due to a change in the ambient temperature, the lock current detection level Ia changes with this. Even if it fluctuates in the range of the detection levels Ia-1 to Ia-2, the problem of erroneous detection of the lock current and the normal current can be avoided.

In the above-described embodiment, an example has been described in which the switching means 3 and 4 are configured using the FETs 15 and 16. However, the present invention is not limited to this, and other switching elements may be used. It is also possible.

[0070]

As described above, in the control apparatus of the electric retractable door mirror according to the present invention, the mask time at the time of activation and the mask time at the time of detection can be set separately, so that the mask at the time of activation can be set. By setting the time to be long and the detection-time mask time to be short, it is possible to prevent a malfunction due to an inrush current generated at the time of starting and to stop the rotation of the door mirror without imposing a load on mechanical parts.

Further, even when the output voltage of the DC power supply (battery) fluctuates, the detection level for detecting the generation of the lock current fluctuates accordingly, so that the generation of the lock current can be ensured. Can be detected. Furthermore, even when the ambient temperature changes, the lock current detection level fluctuates accordingly, so that the occurrence of the lock current can be reliably detected.

Further, by setting a limiting current (threshold) in the switching means, the current flowing through the driving motor can be suppressed to a value equal to or less than the limiting current value. Even in this case, it is possible to suppress an increase in the rotational torque of the door mirror, and it is possible to reduce the occurrence of operation failure without applying unnecessary force to mechanical parts.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a control device for an electric retractable door mirror according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a specific circuit configuration of the control device for the electric retractable door mirror according to one embodiment of the present invention.

FIG. 3 is a characteristic diagram showing a change in a current flowing through a drive motor from when the power is turned on until the door mirror is locked.

4A and 4B are characteristic diagrams illustrating a state of a change in a lock current with respect to a change in a battery voltage. FIG. 4A illustrates a state when the current value is limited by a switching unit, and FIG.

FIG. 5 is a characteristic diagram illustrating a relationship between a change in a battery voltage and a change in a normal current and a lock current, and a state of a change in a current detection level.

FIG. 6 is a characteristic diagram showing a relationship between a change in an ambient temperature, a change in a normal current and a change in a lock current, and a state of a change in a current detection level.

FIG. 7 is a circuit diagram showing a configuration of a conventional example of a control device for an electric retractable door mirror.

FIG. 8 is an explanatory view showing a change in a value of a current flowing through a drive motor from when the power is turned on until a lock current is detected, according to a conventional example.

FIG. 9 shows a lock current when a battery voltage fluctuates,
FIG. 9 is a characteristic diagram illustrating a state of a change in a normal current.

FIG. 10 is a characteristic diagram illustrating a state of a change in a lock current and a normal current when the ambient temperature changes.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Controller 2 Stabilized power supply circuit 3, 4 Switching means 5 PTC element 6 Diode bridge circuit 7 Start-up mask time setting circuit 8, 9 Detection-time mask time setting circuit 10 Reference voltage generation circuit 11, 12 Comparator circuit (comparing means) 13, 14 Flip-flop circuit (switching means) 15, 16 FET R3, R4 Resistance (current detecting means) D4, D5 Diode (rectifying means) SW1 Switching switch M1 Driving motor T1, T2 Connection terminal

────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] February 13, 2001 (2001.2.1)
3)

[Procedure amendment 1]

[Document name to be amended] Drawing

[Correction target item name] Figure 2

[Correction method] Change

[Correction contents]

FIG. 2

Claims (8)

[Claims] An electric retractable door mirror having a function of rotating a door mirror mounted on a vehicle to a retracted position or an upright position by an electric operation. The control device controls the rotational driving of the door mirror. Alternatively, a drive motor for rotating and driving to a standing position, a switch for switching the polarity of a DC power supply mounted on a vehicle to supply a power supply voltage to the drive motor, a changeover switch, and the drive motor Switching means for switching on and off the driving motor, a switching means disposed between the changeover switch and the driving motor, and a current for detecting that a lock current has flowed through the driving motor; Detecting means, which is provided on the drive motor side of the changeover switch, and which is connected to the connection polarity of the changeover switch. A stabilized power supply circuit that outputs a voltage of the same polarity, and driven by an output voltage of the stabilized power supply circuit. And a switching control means for controlling to shut off the switching means with a mask time upon detection when a lock current is detected by the control unit. 2. A control device for controlling the rotation drive of an electric retractable door mirror having a function of rotating a door mirror mounted on a vehicle to a storage position or an upright position by electric operation, comprising: a first connection terminal; A driving motor having a second connection terminal and rotating the door mirror to the retracted position or the upright position; and switching a polarity of a DC power source mounted on a vehicle to apply a forward voltage or a forward voltage to the driving motor. A switch for supplying a reverse voltage, a first switch for switching on and off of the drive motor between the switch and a first connection terminal of the drive motor. First current detecting means for detecting that a lock current has flowed through the drive motor;
And a first rectifying element that applies a forward voltage to the drive motor by bypassing the first switching means and the first current detecting means when a forward voltage is applied. A second switching means for switching the drive motor on and off, and a second switch for detecting that a lock current has flowed through the drive motor, between a second connection terminal of the drive motor and a second connection terminal of the drive motor. 2 current detection means,
And a second rectifying element that applies a reverse voltage to the drive motor while bypassing the second switching means and the second current detection means when applying a reverse voltage. A stabilizing power supply circuit that is installed on the drive motor side of the changeover switch and always outputs a voltage of the same polarity regardless of the connection polarity of the changeover switch; At the time of voltage application, the second switching means is turned on with a startup mask time, and when a lock current is detected by the second current detection means, the second switching means is held with a detection mask time. The switching means is controlled to be cut off, and when a reverse voltage is applied, the first switching means is turned on with a start-up mask time and the first switching means is turned on. Switching control means for controlling to shut off the first switching means with a masking time upon detection when the lock current is detected by the flow detection means. Control device. 3. The switching control means includes a start-up mask time setting circuit that continuously outputs a turn-on detection signal for the start-up mask time from power-on. 3. The control apparatus according to claim 2, wherein at least one of the first switching means and the second switching means is forcibly turned on. 4. The switching control means outputs a lock current detection signal after a detection time mask time has elapsed after the first current detection means detects the occurrence of a lock current.
A detection-time mask time setting circuit, and a second detection-time mask time setting circuit that outputs a lock current detection signal after the detection-time mask time has elapsed after the occurrence of the lock current is detected by the second current detection means. And the first and second
4. The first and second switching means are turned off by a lock current detection signal output from the detection time masking time setting circuit. Electric retractable door mirror control device. 5. The switching control means includes: a reference voltage generation circuit that outputs an output voltage of the stabilized power supply circuit or a voltage obtained by dividing the output voltage as a reference voltage; A start-up mask time setting circuit that continuously outputs a closing detection signal for the mask time; and a lock current detection signal is output after the detection-time mask time has elapsed after the first current detection means has detected the occurrence of the lock current. A first detection-time mask time setting circuit, a first detection-time mask time setting circuit, and a lock current detection signal output from the first detection-time mask time setting circuit, and a reference voltage output from the reference voltage generation circuit. And turning on when an input detection signal output from the start-up mask time setting circuit is supplied, and off when an output signal from the first comparing circuit is supplied. A first switching means for supplying an output signal to the first switching means, and a lock current detection signal is output after the detection time mask time has elapsed after the generation of the lock current is detected by the second current detection means. A second detection-time mask time setting circuit, a second lock-time detection signal output from the second detection-time mask time setting circuit, and a reference voltage output from the reference voltage generation circuit. And an output signal that is turned on when an input detection signal output from the start-up mask time setting circuit is supplied, and is turned off when an output signal of the second comparison circuit is supplied, The control device for an electric retractable door mirror according to claim 2, further comprising: a second switching unit that supplies the second switching unit. 6. At least one of the first switching means and the second switching means includes a switching element having a current limiting function of limiting a current flowing through the drive motor to a predetermined threshold value or less. The control device for an electric retractable door mirror according to any one of claims 2 to 5, wherein 7. The electric motor according to claim 1, wherein an output voltage of the stabilized power supply circuit is increased or decreased according to an increase or decrease of an output voltage of the DC power supply. Control device for retractable door mirror. 8. The output of the stabilized power supply circuit according to claim 1, wherein the output decreases as the ambient temperature rises and rises as the ambient temperature decreases.
The control device for an electric retractable door mirror according to any one of claims 1 to 7.