JP2004148896A - Wiper device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wiper device capable of suppressing temperature rise caused by heat generation of motor windings even when a motor for driving a wiper is locked when performing intermittent operations, and resinifying a motor gear portion. <P>SOLUTION: This wiper device comprises a timer A11 to output the operation command signal according to the signal from a wiper switch 5 when the intermittent operation is selected, and a timer B12 to output the wiper motor drive signal to a wiper motor 1 based on the operation command signal. The timer B12 stops the wiper motor drive signal if the AS signal from a sliding contact switch 2 to indicate the operational position of the wiper motor 1 indicates the OFF-state of a contact which is the stop position of the wiper motor 1, or stops the wiper motor drive signal in a predetermined time t2 after the operation command signal is detected if the AS signal does not indicate the OFF-state. The timer 1 outputs the operation command signal after a predetermined time t1 if the wiper motor drive signal is stopped. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a wiper device, and more particularly to control of a wiper device driven by an electric motor.
[0002]
[Prior art]
A wiper device for a vehicle, when a driver switches off the switch during operation, regardless of the position of the wiper blade at that time, the wiper blade is moved to a predetermined position that does not hinder driving. Acts to stop after moving.
The wiper device is usually a motor device including a rotary DC motor and a speed reduction mechanism, a control device for controlling the operation of the motor device, and a link for converting the rotation operation of the output rotation shaft of the motor device into a swing operation of the wiper arm. It is composed of a mechanism (for example, see Patent Document 1).
[0003]
FIG. 5 shows a basic circuit configuration of a conventional wiper device. In FIG. 5, reference numeral 1 denotes a wiper motor composed of a DC motor, a high-speed driving brush-side power supply terminal Hi for high-speed rotation, a low-speed driving brush-side power supply terminal Lo for low-speed rotation, and the other end of the armature coil. And a terminal connected to the brush. Reference numeral 2 denotes a sliding contact switch, which is composed of a rotating electrode 21 and a fixed electrode 22 that are linked to the rotation of the motor 1. When the rotating electrode 21 makes one rotation, the wiper arm performs one reciprocating swinging operation, and the wiper arm is attached to the tip of the wiper arm at a position where there is no electrical contact between the rotating electrode 21 and the fixed electrode 22. The blade is set in a predetermined position that does not hinder operation. Reference numeral 3 denotes a wiper driving power supply, reference numeral 6 denotes a wiper power supply relay for turning on / off the wiper power supply, reference numeral 7 denotes a motor rotation speed switching relay for switching the motor rotation speed between high and low, and reference numeral 8 denotes an auto stop (AS). ) Power supply. Reference numeral 10 denotes a motor device for a vehicle wiper. The wiper power supply relay 6 and the motor rotation speed switching relay 7 are turned on and off by supplying current to respective relay coils through wiring (not shown).
[0004]
The operation of the wiper device will be described. When the motor rotation speed switching relay 7 is connected to either the Hi side or the Lo side in advance and the wiper power supply relay 6 is turned on, the wiper driving power supply 3 drives the wiper motor 1 at a high speed via the motor rotation speed switching relay 7. Power supply terminal Hi on the brush side or the power supply terminal Lo on the low-speed drive brush side. Since the brush on the other end of the armature coil is connected to the ground (GND) via the terminal e, a current flows through the armature coil, and the wiper motor 1 rotates at high or low speed.
[0005]
On the other hand, when the wiper power supply relay 6 is turned off, the supply of power from the wiper drive power supply 3 to the wiper motor 1 is stopped. However, when power is supplied from the auto stop power supply 8 to the rotary electrode 21 of the sliding contact switch 2 and the rotary electrode 21 and the fixed electrode 22 are electrically connected depending on the rotational position of the wiper motor 1, A power supply voltage supplied from the auto stop power supply 8 is applied as an auto stop signal (hereinafter abbreviated as an AS signal) to the Lo terminal of the wiper motor 1 on the low speed drive brush side via the wiper power supply relay 6, An electric current flows through the armature coil, and the wiper motor 1 rotates at a low speed. Then, when the rotational position of the wiper motor 1 changes and the electrical connection between the rotating electrode 21 and the fixed electrode 22 is cut off, the AS signal is at the ground level because the fixed electrode 22 is grounded via the resistor R1. As a result, the rotation of the wiper motor 1 stops.
[0006]
Therefore, when the wiper power relay 6 is turned off, the wiper motor 1 always advances to the position where the electrical connection between the rotating electrode 21 and the fixed electrode 22 is cut off, regardless of the rotational position of the wiper motor 1 at that time. Then, the wiper blade is stopped by moving the wiper blade to a predetermined position where the operation is not hindered.
Further, the wiper device may have an intermittent operation function of intermittently operating the wiper motor 1. The intermittent operation is performed so that the wiper drive power supply 3 is intermittently applied at a cycle longer than the cycle of the wiper blade making one reciprocation, regardless of whether the wiper switch 5 is at the Hi side or the Lo side. This can be realized by operating the wiper power supply relay 6.
[0007]
[Patent Document 1]
JP 2001-37288 A (pages 8, 9; FIGS. 1 and 2)
[0008]
[Problems to be solved by the invention]
By the way, in such a conventional wiper device, when the load on the motor for driving the wiper is large and the motor cannot operate, the wiper device (motor) is locked and the lock current continues to flow through the motor winding, and the motor winding is stopped. A situation such as heating of the wire occurs. Such a situation occurs, for example, in winter, when the windshield surface is covered with snow, and the wiper blade freezes, or when the snow bites between the glass surface and the wiper blade, the wiper arm cannot swing. to be born. If the heat generation of the motor winding continues for a long time, the motor winding and the motor device harness will be damaged. Generally, when the lock of the wiper device is performing the intermittent operation, the detection is often delayed, and in particular, the detection is often delayed by the rear window wiper.
[0009]
In order to avoid this, conventionally, a method of inserting a circuit breaker or the like in series with the motor has been adopted. Alternatively, assuming that the time during which the lock current flows is not so long, for example, a lock for one or two hours does not cut off the wiring inside the motor, but a method of giving a certain degree of lock strength is set such that the wire is cut off after that. Had been taken.
However, in such a method, although the motor itself can be protected, if the temperature rise becomes large, the resin may be melted and deformed due to a high temperature. In addition, there is a problem that it is difficult to convert the gear housing into resin.
[0010]
The present invention solves this problem, and can suppress a rise in temperature due to heat generation of a motor winding even when a motor for driving a wiper is locked during an intermittent operation, and the motor gear portion is made of resin. It is an object of the present invention to realize a wiper device capable of performing such operations.
[0011]
[Means for Solving the Problems]
To achieve the above object, the present invention provides a wiper motor having a wiper motor operating position detecting means for detecting an operating position of a wiper motor corresponding to a position of a wiper blade attached to a wiper arm and outputting a wiper motor operating position signal. In a wiper device that controls a stop position of the wiper motor in accordance with a wiper motor operation position signal output by an operation position detection unit, a switch unit that outputs an intermittent operation signal when an intermittent operation is selected, and an output of the switch unit First command means for outputting an operation command signal when an intermittent operation signal is detected; and a wiper motor drive signal for driving the wiper motor based on the operation command signal output by the first command means. And second command means for performing the first command, When the operation command signal from the command means is detected, the wiper motor drive signal is output.When the wiper motor operation position signal from the wiper motor operation position detection means is in an operation stop state, the wiper motor drive signal is stopped. If the wiper motor operating position signal from the wiper motor operating position detecting means does not enter the operation stop state, the wiper motor driving signal is stopped after a predetermined time from the detection of the operation command signal, and the first command means When the intermittent operation signal is detected when the wiper motor drive signal is stopped, the operation command signal is output after a second predetermined time.
[0012]
As a result, intermittent operation of the wiper at a predetermined time interval can be realized, and even if the operation of the wiper is stopped for some reason and the wiper motor is locked, the motor winding and the circuit are intermittently operated. Only the current flows. For this reason, a configuration for protecting the motor and the circuit is not required, and the device can be manufactured at a low cost. Further, since the heat generation of the motor can be suppressed, the housing, gears, and the like of the wiper device can be made of resin, and the weight of the device can be reduced. Since the lock of the wiper motor tends to be left as it is during the intermittent operation, it is very useful to suppress the heat generation of the motor during the intermittent operation.
[0013]
The first predetermined time is set to be slightly longer than a time in which the wiper blade performs one reciprocating operation.
Thus, the reciprocating operation can be reliably performed without stopping the wiper blade halfway. Further, when the wiper motor is locked, the flowing current can be reduced as much as possible, and accordingly, the heat generation of the motor can be suppressed and the wiper device can be made of resin. Note that “slightly longer” in the “first predetermined time” mainly means a time during which the wiper blade does not stop halfway.
[0014]
High-speed driving means for driving the wiper motor at high speed, low-speed driving means for driving the wiper motor at low speed, and control means for commonly realizing the functions of the first command means and the second command means. It is characterized by.
As a result, the number of components can be reduced by using a common control means, and the wiper device can be realized at a lower cost.
[0015]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of a wiper device according to the present invention will be described in detail with reference to the accompanying drawings. In the present embodiment, when the wiper device (wiper motor) is locked when the intermittent operation is selected, current is intermittently supplied to the wiper motor to suppress a temperature rise due to heat generation of the motor winding. For example, the motor gear portion can be made of resin. In the following description, the wiper motor is included in the configuration of the wiper device.
[0016]
[Wiper device]
FIG. 1 shows a basic circuit configuration of the wiper device AP of the present embodiment. In FIG. 1, reference numeral 1 denotes a wiper motor composed of a DC motor, a high-speed drive brush side power supply terminal Hi for high-speed rotation, a low-speed drive brush side power supply terminal Lo for low-speed rotation, and the other end of the armature coil. And a terminal connected to the brush.
Reference numeral 2 denotes a sliding contact switch, which is composed of a rotating electrode 21 and a fixed electrode 22 that are interlocked with the rotation of the wiper motor 1. When the rotating electrode 21 makes one rotation, the wiper arm performs one reciprocating swinging operation, and the wiper blade operates at a position where there is no electrical contact between the rotating electrode 21 and the fixed electrode 22 so as not to hinder operation. It fits in the position. Reference numeral 3 denotes a power supply for driving a wiper that applies a positive voltage, reference numeral 4 denotes a control circuit, reference numeral 5 denotes a wiper switch that controls the control circuit 4 to turn on / off the wiper, and reference numeral 6 turns on / off the power supply of the wiper motor 1. Reference numeral 7 denotes a motor rotation speed switching relay for switching the rotation speed of the motor between high and low. The wiper motor 1 and the sliding contact switch 2 form a motor device for a vehicle wiper represented by reference numeral 10. For convenience, the reference numerals in FIG. 1 are the same as those in FIG.
[0017]
FIG. 2 shows a circuit diagram of the control circuit 4 of the present embodiment. In FIG. 2, reference numeral 11 denotes a timer A, reference numeral 12 denotes a timer B, reference numeral 13 denotes a power supply for detecting a wiper position for supplying a positive power supply, R1 and R2 are resistors, C is a capacitor, G1 is an inverter, G2 is an AND gate, and Q is It is an npn transistor (switching transistor).
[0018]
The sliding contact switch 2 in FIG. 1 is a wiper motor operating position detecting means in the claims, the wiper switch 5 is a switch means in the claims, and the timer A11 in FIG. 2 is a first command means in the claims. In addition, the timer B12 corresponds to the second command means in the claims.
[0019]
[Operation of wiper device]
FIG. 3 is a time chart when the wiper device AP of this embodiment is performing intermittent control (during normal operation), and FIG. 4 is a time chart when the wiper device AP is locked. 3 and 4, (a) shows the output signal of the wiper switch 5 input to the C terminal of the control circuit 4, (b) shows the OUT signal of the timer A11, and (c) shows the sliding signal appearing at the B terminal of the control circuit 4. An auto stop signal (hereinafter referred to as an AS signal) indicating electrical contact between the rotating electrode 21 and the fixed electrode 22 of the moving contact switch, (d) is an inverse signal of the AS signal output from the inverter G1, (e) ) Is an integrated signal obtained by integrating the reverse signal of the AS signal by the resistor R2 and the capacitor C, (f) is the output of the AND gate G2 to which (c) and (e) are inputted, and (g) is the OUT signal of the timer B12. It is.
[0020]
The operation in the case where the wiper device AP of this embodiment is performing intermittent control will be described with reference to FIGS. 1, 2 and 3. FIG.
When the wiper switch 5 is turned on, the switch output signal of the wiper switch 5 in FIG. 3A rises from a low level to a high level. This switch output signal is input to the IN1 terminal of the timer A11, and the timer A11 detects this rising and outputs a positive pulse signal of FIG. 3B to OUT. This pulse signal is input to the SET terminal of the timer B12, and the OUT of the timer B12 becomes high level. This OUT is input to the base of the npn transistor Q to make the npn transistor Q conductive. The collector of the npn transistor Q is connected to the wiper driving power supply 3 via the coil of the wiper power supply relay 6 via the terminal A of the control circuit 4, so that when the npn transistor Q becomes conductive, current flows through the coil of the wiper power supply relay 6. Flows, and the wiper power supply relay 6 is turned on.
[0021]
It is assumed that the motor rotation speed switching relay 7 is switched to Hi or Lo in advance by controlling the current flowing through the coil through a line (not shown). This causes the wiper motor 1 to rotate at the Hi or Lo rotational speed.
[0022]
The rotating electrode 21 of the sliding contact switch 2 stopped at a position where there is no electrical contact between the rotating electrode 21 and the fixed electrode 22 moves with the rotation of the wiper motor 1, and eventually the rotating electrode 21 and the fixed electrode 22. Comes in contact with The rotating electrode 21 is connected to a positive voltage wiper position detecting power supply 13 via a resistor R1 via a terminal c of the vehicle wiper motor device 10 and a terminal B of the control circuit 4, and the fixed electrode 22 is connected to the vehicle wiper. The terminal e of the motor device 10 is grounded. Therefore, as shown in FIG. 3C, the AS signal which is the level of the rotating electrode 21 is at a high level at a position where the rotating electrode 21 and the fixed electrode 22 are not in contact, and at the time when the rotating electrode 21 and the fixed electrode 22 are contacted. It goes to low level and returns to high level when there is no contact again. A signal obtained by inverting the AS signal by the inverter G1 is a signal shown in FIG.
[0023]
FIG. 3E shows a waveform obtained by integrating the AS inversion signal by the resistor R2 and the capacitor C. As shown in FIG. 3F, the AND gate G2 outputs a pulse signal representing the rising of the AS signal, which is the logical product of the integrated waveform and the AS signal, to the timer B12 as a reset pulse. This pulse is input to the RESET terminal of the timer B12, whereby the OUT of the timer B12 becomes low level.
[0024]
When OUT of the timer B12 becomes low, the npn transistor Q becomes non-conductive, current does not flow through the coil of the wiper power supply relay 6, and the wiper power supply relay 6 is turned off. Thus, the rotation of the wiper motor 1 is stopped in a state where the rotating electrode 21 and the fixed electrode 22 of the sliding contact switch 2 are not in contact with each other.
[0025]
The signal from the OUT of the timer B12 is also input to the IN2 of the timer A11. When the wiper device AP is performing the intermittent control, the timer A11 detects the fall of the signal from the OUT of the timer B12, and after counting a predetermined time t1 second from this, outputs the positive pulse of FIG. Output a signal. A series of operations are performed again by the pulse signal. This predetermined time t1 corresponds to a first predetermined time indicated in the claims.
[0026]
As described above, while the wiper switch 5 is on, the wiper motor 1 makes one rotation and the wiper blade makes one reciprocating operation at intervals of t1 seconds. Assuming that the time for one reciprocation of the wiper blade is 3 seconds, t1 is about 7 seconds.
[0027]
Next, an operation when the wiper device AP of this embodiment is locked will be described with reference to FIGS. 1, 2, and 4. FIG.
[0028]
When the wiper switch 5 is turned on, the switch output signal of the wiper switch 5 rises from a low level to a high level in FIG. This switch output signal is input to the IN1 terminal of the timer A11, and the timer A11 detects this rising and outputs a positive pulse signal of FIG. 4B to OUT. This pulse signal is input to the SET terminal of the timer B12, the OUT of the timer B12 becomes high level, the npn transistor Q conducts, a current flows through the coil of the wiper power relay 6, and the wiper power relay 6 is turned on. As a result, the wiper motor 1 rotates. The rotating electrode 21 of the sliding contact switch 2 moves with the rotation of the wiper motor 1, and the rotating electrode 21 and the fixed electrode 22 come into contact with each other. Up to this point, the operation is the same as in the case of the intermittent control in FIG.
[0029]
In this state, it is assumed that the load applied to the wiper motor 1 is increased due to, for example, the accumulation of snow between the glass surface and the wiper blade, and the motor cannot operate. In such a case, the lock current continues to flow through the motor winding, and the motor winding generates heat. In order to avoid this, in the present embodiment, the time when the output OUT is at the high level is counted from the time when the timer B12 is set to the time when the timer starts counting and is reset until the counter is reset.
[0030]
In a normal operation in which the lock does not occur, the wiper motor 1 makes one rotation in a predetermined time, whereby the AS signal changes and a reset pulse is input from the AND gate G2 to the RESET terminal of the timer B12. However, if a pulse is not input to the RESET terminal even after a predetermined time during which the wiper motor 1 makes one rotation for the first time when the timer B12 counts, in this embodiment, the timer B12 is longer than the time when the wiper motor 1 normally makes one rotation. After a predetermined time t2, the reset is forcibly performed, the output OUT is turned low, the npn transistor Q is turned off, and the wiper power supply relay 6 is turned off. As a result, the rotation of the wiper motor 1 stops. Assuming that the time for the wiper motor 1 to make one rotation and the wiper blade to make one reciprocation is 3 seconds, t2 is set to about 4 seconds. This predetermined time t2 corresponds to a second predetermined time indicated in the claims. The signal from the OUT of the timer B12 is also input to the IN2 of the timer A11. The timer A11 outputs the positive pulse signal of FIG. 3B to the OUT after a predetermined time t1 seconds from the fall of the OUT signal of the timer B12. Is output.
[0031]
Thus, at the time of locking, a series of operations is repeated in a cycle of time (t1 + t2), and during this time, a current flows for a time t2 when the OUT signal of the timer B12 becomes high. Therefore, even if the wiper device AP is locked, the ratio of the time during which the lock current flows through the motor winding is t2 / (t1 + t2), which makes it possible to suppress heat generation of the motor.
[0032]
By the way, in order to switch the wiper operation, a control means is provided at the front to execute the switching between the high-speed drive function and the low-speed drive function of the wiper motor, and in addition to switching by the driver's switch operation, the wiper motor is switched in accordance with the vehicle speed. The switching of the rotation speed or the switching of the intermittent interval may be performed. When such a control means is provided, the functions of the timer A11 and the timer B12 are shared by the control means, so that the number of parts can be reduced and the wiper can be realized at lower cost. Benefits are obtained.
[0033]
As described above, the present invention has been described along one embodiment, but the present invention is not limited to this embodiment, and various measures can be considered without departing from the spirit of the present invention. For example, in the above description, the wiper power supply relay 6 and the motor rotation speed switching relay 7 are used for switching the motor on / off and the motor rotation speed. However, this can be replaced by a two-circuit, three-contact switch. . In the above description, the wiper device has been described based on the vehicle. However, the wiper device of the present invention can be applied to not only vehicles but also ships and the like.
[0034]
【The invention's effect】
As described above, according to the first aspect of the present invention, the intermittent operation of the wiper at a predetermined time interval can be realized, the operation of the wiper is stopped by some use, and the wiper motor is locked. However, even in the case where the electric current flows through the motor winding and the circuit, the current flows only intermittently. For this reason, a configuration for protecting the motor and the circuit is not required, and the device can be manufactured at a low cost. In addition, since the heat generated by the motor can be suppressed, the housing, gears, and the like of the wiper device can be made of resin, and the weight of the device can be reduced. Further, if the weight is reduced, improvement of fuel efficiency and the like can be achieved in a vehicle and the like. It should be noted that the lock of the wiper motor is easily left unattended during the intermittent operation of the wiper, and thus the present invention has a great effect on measures against heat generation during such lock.
[0035]
According to the second aspect of the present invention, the first predetermined time is set to be slightly longer than the time for which the wiper blade performs one reciprocating operation, so that the wiper blade reliably performs reciprocating operation without stopping halfway. be able to. Further, when the wiper motor is locked, the flowing current can be reduced as much as possible, and accordingly, the heat generation of the motor can be suppressed and the wiper device can be made of resin.
[0036]
According to the third aspect of the present invention, the number of parts can be reduced by using a common control means, and the wiper device can be realized at a lower cost.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a basic circuit configuration of a wiper device according to an embodiment of the present invention.
FIG. 2 is a circuit diagram of a control circuit according to the embodiment of FIG.
FIG. 3 is a time chart when the wiper device of the embodiment of FIG. 1 is performing intermittent control.
FIG. 4 is a time chart when the wiper device of the embodiment of FIG. 1 is locked.
FIG. 5 is a block diagram showing a basic circuit configuration of a conventional wiper device.
[Explanation of symbols]
AP Wiper device 1 Wiper motor 2 Sliding contact switch 3 Wiper drive power supply 4 Control circuit (control means)
Reference Signs List 5 wiper switch 6 wiper power supply relay 7 motor rotation speed switching relay 8 power supply for auto stop (AS) 10 motor device 11 for vehicle wiper 11 timer A
12 Timer B
13 Wiper position detecting power supply 21 Rotating electrode 22 Fixed electrode C Capacitor G1 Inverter G2 AND gate Q Npn transistor R1, R2 Resistance

Claims (3)

A wiper motor operating position detection unit that detects an operating position of the wiper motor corresponding to a position of the wiper blade attached to the wiper arm and outputs a wiper motor operating position signal;
In a wiper device that controls a stop position of the wiper motor according to a wiper motor operation position signal output by the wiper motor operation position detection unit,
Switch means for outputting an intermittent operation signal when intermittent operation is selected;
First command means for outputting an operation command signal when an intermittent operation signal output by the switch means is detected;
Second command means for outputting a wiper motor drive signal for driving the wiper motor to the wiper motor based on an operation command signal output by the first command means,
The second command means,
Outputting the wiper motor drive signal when detecting an operation command signal from the first command means;
When the wiper motor operation position signal from the wiper motor operation position detection means is in an operation stop state, the wiper motor drive signal is stopped,
When the wiper motor operating position signal from the wiper motor operating position detecting means does not enter the operation stop state, the wiper motor driving signal is stopped after a first predetermined time from detecting the operation command signal,
The first command means,
When the intermittent operation signal is detected when the wiper motor drive signal is in the operation stop state, outputting the operation command signal after a second predetermined time;
A wiper device. The wiper device according to claim 1, wherein the first predetermined time is set to be slightly longer than a time in which the wiper blade performs a single reciprocating operation. High-speed driving means for driving the wiper motor at high speed, low-speed driving means for driving the wiper motor at low speed, and control means for commonly realizing the functions of the first command means and the second command means. The wiper device according to claim 1 or 2, wherein:

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