JPS58112855A - Drive mode control device for wiper - Google Patents

Abstract

PURPOSE:To provide the automatic selection of various drive modes of a wiper by furnishing an optical sensor to detect the amounts of rainfall and snow optically. CONSTITUTION:An optical sensor 1 is furnished at a part 2a corresponding to the wiping face of a wiper of a car body 2, and consists of a light-emitting part 3 and a light-receiving part 4 arranged with a facing interval. A hood 5 is provided with an opening window 6, while on the side of the car body 2 facing the opening window 6, a drain port 7 for rain and snow is formed, and the light-emitting part 3 and the light-receiving part 4 are connected to an electric circuit. Raindrops pass the opening window 6, and are led between the light- emitting part 3 and the receiving part 4 to the drain port 7. The wiper is operated in various modes of intermittence, low-speed, and high-speed in accordance with this passing amount of rain and snow.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a wiper drive mode control device that automatically selects various drive modes of vehicle wipers, such as intermittent mode, low speed mode, and high speed mode, depending on the amount of rainfall and snow.

Conventional 1 This type of device has a portion corresponding to the wiper wiper surface, for example 7.
So-called raindrop sensors that detect the impact force of raindrops as vibrations are installed at appropriate locations on the four-door window glass, and the intermittent drive of the wiper is controlled in accordance with the output of this sensor.

However, in such a conventional device, it is necessary to extract a vibration component corresponding to the impact force of raindrops as a vibration component of the vehicle body, and it is necessary to select a detection plate that receives raindrops with a considerably high natural frequency. Therefore, the mass of the detection plate must be reduced or the elastic modulus must be increased. In particular, reducing the mass is greatly influenced by the mass of the raindrops, and a small amount of standing water will substantially lower the natural frequency of the detection plate, making it impossible to obtain stable performance of the raindrop sensor.

In addition, between the detection plate and the vehicle body, a damper has been interposed between the detection plate and the vehicle body in order to attenuate the high frequency components of vibrations of the vehicle body, but providing such a damper requires that its vibration characteristics be matched to the vibration characteristics of the vehicle body. However, the problem was that selecting a damper was troublesome.

Sarani, Conventional device (: The raindrop sensor used detects vibration components according to the frequency of raindrops colliding with the detection plate, so it is difficult to determine the size of individual raindrops, and In the case of snowfall, the impact force is so small that it is almost impossible to detect.

The present invention has been made by focusing on such conventional problems, and includes an optical sensor for optically detecting the amount of rainfall and snow at the wiper wiper surface area of a vehicle. It is an object of the present invention to provide a wiper drive mode control device that automatically selects various wiper drive modes.

The present invention will be described below with reference to the drawings.

@Figures 1 to 3 are diagrams explaining the present invention in detail.

First, to explain the configuration, reference numeral 1 in FIG. It is formed by the light receiving section 4. These light emitting section 3 and light receiving section 4 are covered with a hood 5,
This hood 5 has an opening window 6 formed therein. A rain and snow discharge lower part is formed in the vehicle body 2 facing the opening window 6, and the light emitting section 3 and the light receiving section 4 are connected to an electric circuit (two in series), which will be described later.

Next, an example of the electric circuit shown in FIG. 2 will be described.

The light emitting unit 3 constituting the optical sensor 1 is a light emitting diode LD.
The anode of this light emitting diode is connected to a constant voltage source Vcc (not shown), and the cathode thereof is grounded via a resistor Ro.

Further, the light receiving section 4 constituting the optical sensor 1 is formed by an array of elements such as a phototransistor n, and the collector of the phototransistor PT is connected to the anode of the light emitting diode Φ.

Reference numeral 8 denotes an external optical compensation circuit, and this external optical compensation circuit 8
has a transistor T1 for impedance conversion, the collector of which is connected to the line Vlc of a constant voltage source Vco via a resistor R1, and the emitter thereof is grounded via a resistor R2. transistor T
The pace of 1 is the connection point of resistor Rs and capacitor C1 (
: connected, and one end of capacitor C1 is grounded, while
The resistor Ri is connected to the grounded emitter 6 of the phototransistor PT via a resistor R4. Note that the collector of the transistor T1 is connected to the base f2 of the transistor n.

Reference numeral 9 denotes a first stage amplifier, one end of a capacitor C2 of this first stage amplifier 9 is connected to the upstream side of the resistor & of the external optical compensation circuit 8, and the other end of the capacitor C2 is connected to a transistor T.
Connected to pace 2. The base of the transistor T2 is connected to its collector via a resistor Rs, the collector of which is connected via a resistor to the line vL, the collector of which is connected to ground.

Reference numeral 10 denotes a second stage amplifier, and the collector of the transistor T2 of the first stage amplifier 9 is connected to the non-inverting input terminal of the voltage comparator A1 via a capacitor Cs. This non-inverting input terminal is grounded via a resistor R7, and the inverting input terminal is grounded via a resistor k. Further, a resistor & is connected between the inverting input terminal and the output terminal of the voltage comparator A1.

The output end of the voltage comparator A1 is connected to one end of the resistor R1o that constitutes the smoothing circuit 11, and the other end is connected to the capacitor Ca.
One end C of the resistor R1 is connected through the prototype circuit formed by the IC51C4 and the resistors R11+R12.

The other end of this resistor R+s is connected to the non-inverting input terminal of the voltage comparator A2, and its inverting input terminal is connected to the output terminal.

The output terminal of the voltage comparator 2 is the voltage comparator A of the comparator circuit 12.
3 expansion/inversion input, output end (: connected via resistor RS4,
A resistor RM is connected between the output terminal and the non-inverting input terminal of the voltage comparator As. Further, the inverting input terminal of the voltage comparator A3 is grounded via a capacitor C7, and is also connected to the sliding end rj on the low voltage side of the variable resistor (2). One end of this variable resistor (2) is connected to the line VL, the other end is grounded via a resistor Rs, and the sliding end (r) on the high voltage side is connected to the inverting input terminal of the voltage comparator (4). Further, the output terminal of the voltage comparator As is connected to the transistor T through a resistor R17.
s, its emitter is grounded, and its collector is connected to one end of each of the excitation coils of the relays Rn and RY2 connected in parallel, and the other end of each excitation coil is connected to the line vL (two series). One end of the excitation coil of the relay RY3 is further connected to the line V1., and the other end is connected to the collector 32 of the transistor T4.The emitter of the transistor T4 is grounded; The inverting input terminal of the voltage comparator A4 is grounded via a capacitor C8, and the non-inverting input terminal is connected to one end of each of resistors R+s and Rw. The other end of the resistor R+a is connected to the output end of the voltage comparator A2 of the smoothing circuit 11, and the other end of the resistor R1e is connected to the output end C of the voltage comparator A2.
It is two tangents.

Each relay RYI, RY2. Each contact of RY3 8c+l
&2e $218Qs+80s constitutes a switching circuit 13 that selects the wiper drive mode, and this switching circuit 13 connects to the wiper drive circuit 14 (two tangents. Relay RY
One end of the normally closed contact 8c1 of I is connected to the intermittent amplifier h,
The other end is the normally open contact of relay RY2, normally closed contact scs
One end of each (=connected to each other. Also, the other end of the normally open contact is connected to the high-speed mode terminal It of the wiper drive motor M.
The normally closed contact & the other end of the wire are connected to the low speed mode terminal respectively. The upstream terminal 4 of the motor M is connected to the positive terminal side of the batch 9B (not shown) (to be connected to the B line B).
This B line is connected to the other contact of an auto-stop switch As whose one contact is grounded, and its common end is connected to the intermittent amplifier M.

Note that the power for the intermittent amplifier M is supplied from the B line.

Furthermore, one end of the normally closed contact of relay RYI is connected to relay R.
One end of the normally open contact So2 of Y3 is connected, and the other end is connected to the anode of the diode D1.

The anode of this diode D1 is connected to the intermittent amplifier M via a normally closed contact 802, and its cathode is grounded via a wiper switch. The cathode of the diode D2 is connected to the cathode of the diode D1, and the anode of the diode D2 is connected to the pace of the transistor TI via a resistor R21. The emitter of the transistor Ts is connected to the B line, and the collector thereof is connected to the line ML of the constant voltage power supply (2).

Next 1: The operation will be explained with reference to FIG.

For example, if it is necessary to drive the wipers during rain, first close the wiper switch (■). As a result, power is simultaneously supplied from the constant voltage power supply Vcc and battery B to each circuit. The raindrops pass through the opening window 6 and also pass between the light emitting section 3 and the light receiving section 4 to reach the discharge lower. As the raindrops pass, the light emitted from the light emitting diode W is scattered by the raindrops, so that the amount of light received by the transistor etc. decreases.

As a result, the signal obtained from check point (a) is
As shown in Figure (a), the signal LOC caused by the external light is a superposition of the signal LOC caused by the raindrop C; the signal W caused by the external light is formed by the resistor Rs y C+ of the external light compensation circuit 8. Since it is supplied to the pace of transistor T1 through the integrating circuit, the current of transistor T1 is
impedance changes. Therefore, the signal LIJ (Fig. 3~) at the check point (b) is opposite in phase to the signal W caused by the external light C, and from the check point (c) only the signal W due to the scattering of raindrops is amplified. can be obtained.

The signal LP from the raindrop C2 is smoothed by the smoothing circuit 11, and the voltage comparators As and A4 of the comparator circuit 12 compare the signal levels. In this case, when the output level of the smoothing circuit 11 is low, that is, when the amount of rainfall is small, the voltage comparator A
None of the outputs of l11A4 are inverted. therefore,
Since the excitation coils of relays RYI, RY2, and RY3 are not energized, each normally closed contact 5c11S
c2. sc! 1 remains closed, only the intermittent amplifier M operates and the wiper operates in an intermittent mode, and the wiper is driven in an intermittent mode by the action of the auto-stop switch A-.

Next, when the amount of rainfall increases and the output level of the smoothing circuit 11 rises slightly, the output of the voltage comparator As is inverted and the transistor T5 is turned on, so that each excitation coil of the relays RY'l 1RY2 is energized. Therefore, normally closed contact &1
opens, the normally closed contacts Fji:, 2 open, and the normally open contacts Fji:, 2 close. For this reason, intermittent Amp M stops working,
A current flows toward the low speed mode terminal of the motor M, and the wiper is driven in the low speed mode.

Further 4: When the amount of rainfall increases and the output level of the smoothing circuit 11 rises further, the output of the voltage comparator is inverted and the excitation coil of the relay RY3 is also energized by turning on the transistor T4. Therefore, by opening the normally closed contact &S and closing the normally open contact -, the high speed mode terminal HX of the motor M
Current flows in both directions and the wiper is driven in high speed mode.

In the case of snowfall, the operation is similar to that described above, except that the light from the light emitting diode LD is struck by lightning and the attenuation of the light is detected by the transistor PT. Further, in this embodiment, the optical sensor 1 is of a so-called transmission type, but it is of course possible to use a reflection type.

As explained above, according to the present invention, there is provided an opening window provided in the wiper-wiping surface area of the vehicle body to allow rain and snow to pass through, an optical sensor provided in the opening window to detect passage of rain and snow, and an optical sensor provided in the opening window to detect passage of rain and snow. It is equipped with a wiper that wipes the rain and snow in a mode that is set according to the amount of rain and snow detected by the sensor, so the wiper drive mode can be automatically selected depending on the size of raindrops and the frequency of collisions. (= Unlike conventional devices, the influence of vibration components of the vehicle body is removed, so there is no need to consider the natural frequency. Also, unlike conventional devices, the structure does not detect changes in rainfall as changes in vibration, so the damper Since there is no need to use the damper repeatedly, there is no risk of deformation of the damper or change in vibration characteristics due to repeated stress from external vibrations.In addition, detection can be performed not only during rain but also during snow.

[Brief explanation of the drawing]

Fig. 1 is a schematic configuration diagram of an optical sensor showing an embodiment of the present invention, Fig. 2 is an electric circuit diagram showing an embodiment using the optical sensor, and Fig. 3 (N, (b), (c) is a waveform diagram of the signal obtained from the optical sensor, and Fig. 3(a)
is a check point (a), and Figure 3 (b) is a check point (b)
, and FIG. 3(c) show those at check point H, respectively. DESCRIPTION OF SYMBOLS 1... Optical sensor, 3... Light emitting part, 4... Light receiving part, 6... Opening window, 11... Smoothing circuit, 12... Comparison circuit. Figure 1 Figure 3

Claims (2)

[Claims] (1) An aperture window installed in a portion of the vehicle body corresponding to the wiper wiper surface to allow rain and snow to pass through; an optical sensor installed in the aperture window to detect the passage of rain and snow; and an optical sensor to detect rain and snow. 1. A wiper drive mode control device comprising: a wiper that wipes in a mode set according to a passing amount. (2) An optical sensor formed by a light emitting part and a light receiving part, a smoothing circuit that smooths the output of this sensor by obtaining a signal corresponding only to the amount of passing rain and snow, and the output of this smoothing circuit. The wiper drive according to claim 1, characterized in that the wiper drive comprises a comparison circuit that compares the size with various predetermined setting values according to the size, and wipes the wiper in a selected mode based on the output of the comparison circuit. Mode control device.