JPS6039308Y2 - Washer interlocking wiper drive device - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] The present invention is a washer-linked wiper mainly suitable for vehicles, which has a function to operate the wiper motor a fixed number of times in conjunction with the turning on of the washer switch in the wiper motor drive device. This relates to a drive device.

[Prior art]

A wiper drive device having a washer interlocking function is configured to operate the wiper motor for a predetermined operating time after a predetermined delay time when a washer switch is turned on.

Here, the one delay time is necessary so that the wiper blade does not operate before the washer motor is sufficiently operated, and the wiper motor is stopped during this delay time.

On the other hand, it is necessary to set the actuation time to be sufficiently long for one delay time.

Known techniques, such as Japanese Utility Model Publication No. 52-20817, suggest that the delay time and activation time described above be realized by one common capacitor.

When obtaining delay time and activation time with one capacitor,
Since the charging time constant and the discharging time constant are significantly different, it is not easy to adjust the time constant circuit to satisfy the rain constant, and if the washer switch ON time changes and the capacitor's charge changes, the discharging time also changes. As a result, each time the washer switch is operated, the operating time of the wiper blade changes depending on the operation.

[Purpose of invention]

In view of the above points, an object of the present invention is to provide a washer-linked wiper drive device that can obtain a constant wiper operating time after the washer switch is closed, regardless of the length of time the washer switch is turned on. It is something to do.

〔Example〕

An embodiment of the present invention will be described below based on the drawings.

In the attached drawings, 1 is an onboard battery, 2 is an ignition switch, 3 is a wiper fuse, 4 is a 3-brush wiper motor, 4a is a motor interlocking contact for automatically stopping the wiper blade in a fixed position, 5 is a wiper operation selection switch,
6 is a washer motor, 7 is a washer switch, and 8 is a washer-linked wiper drive device according to the present invention.

In this embodiment, the washer interlocking wiper drive device 8
is configured to particularly control the intermittent operation of the wiper motor 4 and the washer interlock operation, and the high speed interlock operation and the low speed interlock operation of the wiper motor 4 are configured to control each brush of the wiper motor 4 when the selection switch 5 is switched to the corresponding selection position. The energizing path is connected to the

The washer interlocking wiper driving device 8 includes a first transistor Tr1, a capacitor C1, a diode D2, a resistor R1,
It consists of a well-known wiper intermittent drive device made up of R7, R8 and an electromagnetic relay RL, and a washer interlocking control device made up of other circuit elements that utilize the electromagnetic relay RL.

Tr2 is a second transistor connected in parallel with the first transistor Tr1, R3 and R6 are voltage dividing resistors that form a bias for the second transistor Tr2, C3 is an operating time setting capacitor connected in parallel with the bias circuit, and Tr3 is a third transistor.
It is a transita.

The resistors R2 and R1 constitute a bias circuit that supplies a base current to the third transistor Tr3 when the washer switch 7 is turned on, and includes a delay capacitor C2.

C4 is a capacitor for noise protection, and C4 is a current limiting resistor with a small value.

Dl is a reverse surge absorption diode.

First, intermittent wiper operation will be explained in the embodiment shown in the figures below.

When the ignition switch 2 is closed and the selection switch 5 is in the stop position, the contact of the electromagnetic relay RL and the fixed position stop contact 4
Since a is at the position shown in the figure, the point a of capacitor C1 is OV.
, point b is charged to the power supply voltage VB.

Next, when the selection switch 5 is moved to the intermittent position, the base current of the transistor Tr1 flows, the transistor Tr becomes conductive, the relay RL is energized, and the wiper motor 4 starts rotating.

When the wiper motor 4 starts rotating, the fixed position stop contact 4a moves to the power supply side, and while the wiper motor 4 is rotating, the point a of the capacitor C1 becomes VB and the point b becomes about IV.

When the wiper motor 4 completes one rotation, the fixed position contact 4a moves to the ground side again, so the point a of the capacitor C1 becomes OV, point b
The point becomes -(VB-1)V, the transistor Tr1 is cut off, the electromagnetic relay RL is deenergized, and the power supply to the wiper motor 4 is cut off.

At the same time, a short circuit for dynamic braking is formed, and the wiper motor 4 immediately stops.

Thereafter, since the capacitor C3 is charged by the resistor R1, the potential at point b of the capacitor C1, which has become -(VB-i)V, gradually increases.

When the potential at point b reaches approximately 1■, transistor Tr1 becomes conductive, electromagnetic relay RL is energized, and wiper motor 4 is activated again.
begins to rotate.

Thereafter, this process is repeated, and the wiper motor 4 operates intermittently.

In this intermittent operation, the time period during which the wiper motor is stopped can be freely set using the resistor R1 and the capacitor C1.

Note that the resistor R3 is for current limitation, and the diode D2 is for protection between the emitter and the emitter of the transistor Tr1.

Next, the wiper motor is activated in conjunction with the washer switch.

This section explains the washer-linked operation.

Ignition switch 2 is closed and selection switch 5 is set to O.
At the FF level, capacitors C2 and C3 are in a discharged state.

Turn on washer switch 7.

(closed), the delay capacitor C2 starts to be charged at the same time as the washer motor 6 starts rotating, and after a predetermined delay time, the base potential of the transistor Tr3 reaches approximately (VB
-0, 5) V, transistors Tr3 and Tr2 become conductive, energize electromagnetic relay RL, and wiper motor 4 starts rotating.

Since the delay capacitor C2 is connected in parallel with the base and emitter of the transistor Tr, the charging voltage is fixed at a constant value.

On the other hand, when transistor Tr3 becomes conductive, capacitor C3
is charged instantly (as mentioned above, the value of resistor R6 is small) and becomes fully charged immediately.

Therefore, no matter how long the time that the switch is closed, the charge on the capacitor C3 does not increase any further and remains constant.

Next, when the washer switch 7 is opened, the transistor Tr
3 is instantaneously interrupted when the delay capacitor C2 is slightly discharged through the resistor R1, but the charge in the capacitor C3 flows as the base current of the transistor Tr2 through the bias circuit consisting of the voltage dividing resistors R3 and R. In order to continue, the wiper motor 4 continues to rotate for a predetermined period of time.

When the fully charged capacitor C3 is discharged by a predetermined amount as described above, the transistor Tr2 is turned off and the electromagnetic relay RL is deenergized, and the wiper motor 4 rotates to the stop position and stops.

Here, the delay time from when the washer switch 7 is turned on until the wiper motor is activated can be freely set using the resistor R2 and the capacitor C2.

Also, after opening washer switch 7, electromagnetic relay R
The wiper motor operating time until L is deenergized can be freely set by resistor R3 and capacitor C3.

Moreover, in setting this operating time, the length of the closing time of the washer switch 7 and the length of the delay time caused by the resistor R2 and the capacitor C2 have no influence at all.

In addition, in this embodiment, when the intermittent operation of the wiper motor 4 and the washer-linked operation are operated simultaneously, and even when only the washer-linked operation is stopped after a while, the capacitor C1 is drained at the moment the wiper motor 4 stops. Since point a is 0■ and point 6 is -(VB-1)V, the transistor Tr□ is first in a cutoff state, so there is an advantage that the intermittent operation after the washer interlocking operation is stopped starts from the rest time.

[Effect of idea]

As described above, in this invention, the electromagnetic relay that was conventionally used for special drives such as intermittent wiper operation can be used for washer-linked wiper drive, and it is constructed with an extremely small number of parts. It has the advantage of being small, inexpensive, and highly reliable.

Furthermore, since the circuit is configured to start driving the wiper motor after a predetermined delay time after the washer switch is turned on, and to charge the operating time setting capacitor, the washer switch can be used regardless of the length of time the washer switch is turned on. An excellent effect is that the wiper motor can continue to be driven for a certain period of time after opening.

[Brief explanation of the drawing]

The accompanying drawing is an electrical wiring diagram showing one embodiment of the device of the present invention. 4... Wiper motor, 5... Wiper operation selection switch, 6... Washer motor, 7
...Washer switch, RL...Electromagnetic relay, Tr, ...First transistor, Tr
2...Second transistor, Tr3...
Third transistor, R3, R6... Voltage dividing resistor, C
3...Resistance for setting operating time, R2...
Resistor, C2...Delay capacitor.

Claims (1)

[Claims for Utility Model Registration] A wiper drive device including an electromagnetic relay that drives a wiper motor, and a first transistor that connects in parallel to the first transistor and energizes the electromagnetic relay. a voltage dividing resistor that supplies the base current of the second transistor; an operating time setting capacitor connected in parallel with the voltage dividing resistor; and a parallel connection of the voltage dividing resistor and the capacitor. A third transistor is connected in series to the circuit, a Niwanobu capacitor is connected substantially in parallel between the pace emitters of the third transistor, and the delay capacitor is connected by turning on a switch that operates the washer motor. a resistor that supplies a base current of the third transistor.