JPH0114060B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a washer-linked intermittent wiper device configured so that the wiper always operates a set number of times when the washer is operated.

A conventional washer-linked intermittent wiper device was constructed as shown in FIG.

That is, in FIG. 1, 1 is a wiper motor, 2 is a fixed position stop switch, 3 is a motor drive relay, 4 is an intermittent wiper circuit section composed of a capacitor 4a, a resistor 4b, a transistor 4c, etc., and 5 is an intermittent wiper Start switch, 6 is capacitor 6a, 6b, transistor 6c, resistor 6d
7 is a washer motor, and 8 is a washer start switch. The time constant of the intermittent operation is determined by the resistor 4b and the capacitor 4a.

In order to reduce the size of such a configuration, chip parts such as resistors and transistors can be used, but aluminum electrolytic capacitors cannot be made smaller because they are not made into chips, and tantalum electrolytic capacitors cannot be made into chips. There are some types, but those with a large capacity are expensive and are at a significant disadvantage in terms of cost.

It is possible to reduce the capacitor capacity to make it as compact as possible, but in order to match the time constant, the resistance value must be increased, so the resistor 4b,
Since 6d is also a bias resistor for the transistors 4c and 6c, there is a limit to how the transistors can operate normally, and the resistance value cannot be made very large.

It is also possible to use Darlington-connected transistors as the transistors 4c and 6c, but since the collector-emitter saturation voltage is high, there will be a loss of voltage applied to the motor drive relay 3, and the voltage reduction characteristics as a circuit unit will be affected. Getting worse.

As described above, it has been extremely difficult to reduce the size of the conventional configuration.

The present invention aims to eliminate the above-mentioned conventional drawbacks and to provide a washer-linked intermittent wiper device that is inexpensive and can be downsized.

An embodiment of the present invention will be described below with reference to FIG. 2 of the drawings.

First, one embodiment shown in FIG. 2 will be explained. 9 is a battery, 10 is a wiper motor, 11 is a battery, and 11 is a wiper motor.
is a fixed position stop switch, 12 is a motor drive relay, 13 is a capacitor 13a, a variable resistor 13b,
Resistors 13c, 13d, transistors 13e, 13
In the intermittent operation circuit section constituted by f, the capacitor 13a is for the time constant of the intermittent time, the transistor 13e is a transistor for driving the motor drive relay 12, and the transistor 13f is for driving the bias circuit of the transistor 13e. The variable resistor 13b is the transistor 13 for
is the bias resistance of f. 14 is an intermittent wiper start switch and normally closed contact 1 is connected to battery 9.
4a and a normally open contact. Reference numeral 15 denotes a program operation circuit section, which includes a delay time constant capacitor 15a, a delay time constant resistor 15b, and a holding time constant capacitor 15.
c, holding time constant resistor 15d, capacitor 15c
It is composed of a charging transistor 15e for charging, a discharging resistor 15f, and a protective resistor 15g.

Further, 16 is an OR circuit for the signals of the intermittent operation circuit section 13 and the program operation circuit section 15, and a resistor 16 connected to the normally open contact of the intermittent wiper switch.
a, diodes 16b and 16c, and a resistor 16d. 17 is a washer motor,
18 is a watch start switch.

Regarding the operation of this configuration, when the wiper is in the stop position as shown in FIG. 2 and the intermittent wiper start switch 14 is in the closed position 14a, both ends of the capacitor 13a are charged to the power supply voltage. Here, switch the intermittent wiper start switch 1.
If you switch 4 to the normally open contact side, transistor 13
f, 13e immediately become conductive, the motor drive relay 12 turns on, and the wiper motor 10
is activated. When the wiper motor 10 operates, the normally open contact of the fixed position stop switch 11 closes, and the potential at point A becomes twice that of the battery 9, but the transistor 13
The charge of the capacitor 13a is discharged to the base circuit of f, and the potential at point A drops to almost zero potential. Next, when the wiper comes to the stop position, the normally closed contact of the fixed position stop switch 11 closes and the point A becomes a negative power supply potential, so the transistor 13f becomes non-conductive and the wiper enters a rest period. Eventually, the capacitor 13a is charged by the variable resistor 13b, and when point A becomes a positive potential, the transistor 13f becomes conductive again and the wiper operates.

In this way, the intermittent wiper operation is performed by the intermittent operation of the transistor 13f, and the intermittent operation time of the transistor 13f is determined by the variable resistor 13b and the capacitor 13a.

Further, when the washer start switch 18 is closed, the washer motor 17 is operated to spray the washer fluid onto the front window. At the same time, charging of the delay time constant capacitor 15a starts, and when a certain potential is reached, the charging transistor 15e becomes conductive, and charging of the holding time constant capacitor 15c starts. When the charging potential of the holding time constant capacitor 15c exceeds a certain value, the transistor 13f becomes conductive via the diode 16c of the OR circuit 16, and the transistor 13e also becomes conductive, turning on the motor drive relay 12 and operating the wiper motor 10. do. The operating time of the wiper motor 10 is determined by the operating time of the transistor 13f, and the operating time of the transistor 13f is determined by a time constant determined by the holding time constant capacitor 15c and the resistor 15d.

In the above configuration, since the motor drive relay 12 is driven in two stages by the transistors 13e and 13f, high resistance can be used as the resistors 13b and 15d of the bias circuit of the transistor 13f, and therefore the capacitors 13a and 15c have a small capacity. , small and low-cost capacitors can be used.

In addition, there is no need to use transistors with high h _FE , which is advantageous in terms of price. Furthermore, since the normally closed contact 14a of the intermittent wiper start switch is connected to the battery 9, even if the intermittent wiper start switch is switched to the normally closed contact side and then immediately switched to the normally open contact side during the period when the wiper is not operating, the intermittent wiper start switch When wiper start switch 14 is turned off, capacitor 1
3a is charged instantly and the potential at point A returns to its initial state, so the intermittent wiper start switch 1 is immediately turned on.
4 is closed, the wiper motor 10 continues to operate.

Since the washer-linked intermittent wiper device of the present invention is configured as described above, the long-term intermittent wiper operation and the washer-linked wiper operation time can be set by increasing the resistance value instead of the capacitor capacity, and by using a transistor with high h _FE . It is less expensive because there is no need to use a switch, and the capacitor capacity can be reduced, which is advantageous in terms of miniaturization, and it is also advantageous in terms of cost. Furthermore, by providing a normally closed contact for the intermittent wiper start switch connected to the battery, Even if the intermittent wiper start switch is repeatedly opened and closed quickly, as long as it is closed, the wiper will always operate, which has the advantage of being effective for vehicle operation and ensuring safety, and is of great practical value.

[Brief explanation of drawings]

FIG. 1 is an electrical circuit diagram of a conventional washer-linked intermittent wiper device, and FIG. 2 is an electrical circuit diagram showing an embodiment of the washer-linked intermittent wiper device of the present invention. 9... Battery, 10... Wiper motor, 1
DESCRIPTION OF SYMBOLS 1... Fixed position stop switch, 12... Motor drive relay, 13... Intermittent operation circuit section, 13a...
Capacitor, 13b...Variable resistor, 13c, 13
d...Resistor, 13e, 13f...Transistor,
14... Intermittent wiper start switch, 14a...
Normally closed contact, 15...Program operating circuit section, 15
a... Capacitor for delay time constant, 15b... Resistor for delay time constant, 15c... Capacitor for holding time constant, 15d... Resistor for holding time constant, 15e... Charging transistor, 15f... Discharging resistor, 15g
...protective resistor, 16...OR circuit, 16a...resistor, 16b, 16c...diode, 16d...
Resistor, 17... Washer motor, 18... Watcher start switch.

Claims (1)

[Claims] 1 A wiper motor, a fixed position stop switch that operates at the position of the wiper motor, a relay that drives the wiper motor, a first transistor that drives the relay, and a second transistor that drives the base of the first transistor. a transistor, a resistor with one end connected to a power source, a capacitor with the other end of the resistor connected to a normally closed contact of the relay, and with which the second transistor is intermittently operated; and the other end of the resistor. and the base of the second transistor, an intermittent wiper start switch having a normally closed contact connected to the power supply and a normally open contact connected to the base of the second transistor, a washer motor, and a washer start switch for driving the washer motor. , a capacitor that is charged during the washer operation, a charging transistor that is operated by the charging potential of this capacitor, and a capacitor that is charged by the conduction of this charging transistor.
and another resistor connected to the base of the second transistor, which controls the charging potential of the capacitor so as to determine the operation time of the second transistor.