JP3107710B2 - Speed sensitive intermittent wiper device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wiper device for wiping raindrops attached to a windshield of an automobile, and more particularly to a vehicle speed-sensitive intermittent wiper device capable of automatically changing an intermittent rest time of a wiper according to a vehicle speed. It is.

[0002]

2. Description of the Related Art As a conventional vehicle speed-responsive intermittent wiper device, as disclosed in Japanese Patent Application Laid-Open No. 56-60749, a vehicle speed signal is input, and the intermittent idle time of the wiper is changed linearly with a change in vehicle speed. It is common.

[0003]

However, the amount of rainfall hitting the windshield does not change linearly with changes in vehicle speed, and therefore, it is not possible to wipe out raindrops in all vehicle speed ranges with proper intermittent downtime. Was. There is an example of using a rainfall sensor or the like as a method of setting the intermittent pause time according to the rainfall, but this has a disadvantage that it is expensive. Accordingly, an object of the present invention is to provide a vehicle speed-sensitive intermittent wiper that can be wiped with an appropriate intermittent downtime according to a change in the amount of rain hitting a windshield due to a change in vehicle speed, and can suppress a cost increase due to the addition of a rainfall sensor or the like. It is to provide a device.

[0004]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a vehicle speed sensitive intermittent wiper device in which the intermittent idle time of the wiper is variable according to the vehicle speed. Means for determining the ratio of the magnitude of the vector sum to the vehicle speed in the horizontal direction to the vertical drop speed of the raindrop; one cycle of the wiper when the vehicle is stopped is divided by the above ratio; and the operating time of the wiper is calculated from the divided value. , A means for calculating the intermittent pause time of the wiper during traveling, and a means for controlling the wiper in accordance with the calculated intermittent pause time.

[0005]

The amount of rain falling on the windshield is proportional to the vector sum of the falling speed of the rain (vertical direction) and the vehicle speed (horizontal direction). The magnitude of this vector sum is equivalent to the length of the hypotenuse of a right-angled triangle having two sides at right angles to the rain fall speed and the vehicle speed. Therefore, by adjusting the intermittent operation cycle of the wiper so as to be inversely proportional to the vector sum, it is possible to wipe off rain with an appropriate intermittent rest time according to a change in vehicle speed. The relationship between the intermittent pause time and the vehicle speed obtained as described above does not have a linear change characteristic as in the related art, but a fractional function change characteristic.

[0006]

1 shows a basic configuration of a vehicle speed sensitive intermittent wiper device according to the present invention. Reference numeral 1 denotes a control unit, in which a microcomputer 2, input interfaces 3 to 6, and an output interface 7 are incorporated. The wiper switch 10 includes an intermittent volume 11 and an intermittent mode switch 12, and signals of the volume 11 and the mode switch 12 are input to the microcomputer 2 via input interfaces 3 and 4, respectively. The volume 11 is manually adjusted by the driver according to the amount of rainfall. Mode switch 12
Is operated by the driver to various positions such as "stop", "intermittent", "low speed", "high speed", etc. When the driver operates "intermittently", an intermittent pause time described later is automatically set according to the vehicle speed. adjust. The vehicle speed sensor 13 is a sensor for detecting a vehicle speed, and a vehicle speed signal is input to the microcomputer 2 via the input interface 5. The wiper motor 14 is a motor for wiping the wiper, and is controlled by the microcomputer 2 via the output interface 7. The operation signal of the wiper motor 14 is input to the microcomputer 2 via the input interface 6,
The time when the motor 14 is stopped is detected. Therefore, the motor 1
The period from the stop of 4 to the start of the next drive is the intermittent pause time.

Next, a description will be given of a method of calculating the intermittent rest time of the wiper in the intermittent wiper device according to the present invention. Rainfall impinging on the windshield 20 of a motor vehicle running at the vehicle speed V _v, as shown in FIG. 2, it is proportional to the vector sum V _B of the falling velocity V _R and the vehicle speed V _v of rain. The fall velocity V _R of rain are those obtained empirically, for example, about 6.4 m / sec. This value V _R is stored in advance in the microcomputer 2 memory. The magnitude of the vector sum V _B is given by the following equation.

[Number 1] (referred to as rainfall coefficient _{k) V B = (V R} 2 + V v 2) 1/2 ... (1) the ratio of the rainfall in rainfall and when the vehicle is stopped during running is as follows.

## EQU2 ## k = V _B / V _R = (V _R ² + V _v ² ) ^1/2 / V _R (2) The rainfall coefficient k is as shown in FIG. 3 when the vehicle is stopped (V _v = 0). 1
This is an irrational function characteristic that increases as the vehicle speed increases.

FIG. 4 is a time chart showing the operation of the wiper at the time of stopping and running. T _W is the operation time of the wiper, T _O is the intermittent halt time at vehicle speed 0 (when stopped), and T _V is the intermittent halt time at vehicle speed V _v .
The wiper operation time T _W is a time required for the wiper to reciprocate once and is a constant value. In order to obtain an even wiper amount of the wiper irrespective of the change in vehicle speed, it is necessary to set the interval between the rainfall hitting the windshield during one cycle (T _O + T _W ) when stopping and the one cycle (T _V + T _W ) during running. What is necessary is to make the rainfall hitting the windshield equal. Since the total rainfall for one cycle when the vehicle is stopped is proportional to _{V R × (T O + T} W), the total rainfall for one cycle at the time of running is proportional to _{V B × (T V + T} W),

V _R × (T _O + T _W ) = V _B × (T _V + T _W ) (3) Rewriting the above equation gives the following equation.

(Equation 4) From the equation (4), the intermittent pause time T _{V at the} vehicle speed V _v is obtained by the following equation.

(Equation 5)

[0009] above relationship between the intermittent pause time T _V and the vehicle speed V _v determined as equation is a fractional function change characteristics as shown in FIG. That is, in the low vehicle speed range, the intermittent pause time decreases significantly as the vehicle speed increases, whereas in the high vehicle speed range, the intermittent pause time hardly changes even when the vehicle speed increases. The driver can judge the amount of rainfall and adjust the intermittent volume 11 to change the characteristics in a plurality of stages as A to D. This is a case where the rainfall increases in order from A to D in FIG.

[0010] In the above description has been sought rainfall coefficient k from equation (2), instead of this, by using the inclination angle θ of the vector V _B relative to the horizontal, it may be determined rainfall coefficient k by the following equation.

In this case, equation (5) can be rewritten as follows.

[Equation 7] _{T V = (T O + T} W) sin θ-T W However, this formula also, Chigae what representation method, calculation method is substantially
This is similar to equation (5).

Equations (1) to (5) represent the intermittent pause time T _V
This is merely an example for determining the intermittent pause time, and the intermittent pause time may be determined by other methods. For example, the intermittent operation time T _V during traveling may be obtained by dividing the intermittent operation period T _O + T _W when the vehicle is stopped by the rainfall coefficient k. Also, instead of the rainfall coefficient k, the rain fall velocity V
Using vector sum V _B between the _R and the vehicle speed V _v, by dividing the intermittent operation period T _O + T _W at stop at the magnitude of the vector sum V _B, may be obtained intermittent pause time in the vehicle speed V _v .

[0012]

As is apparent from the above description, according to the present invention, the set value V corresponding to the vertical drop speed of the raindrop is obtained.
_R and horizontal vehicle speed V _V Vector obtains the magnitude of the sum V _B, since the adjustment the intermittent pause period T _V of the wiper so as to be inversely proportional to the magnitude of the vector sum V _B, rain proper intermittent pause time T _V in accordance with the vehicle speed change between Can be dispelled. Also,
It is not necessary to use a special sensor such as a rainfall sensor.
Since the intermittent suspension period can be obtained according to the above, there is an advantage that the configuration can be made inexpensively.

[Brief description of the drawings]

FIG. 1 is a basic configuration diagram of a vehicle speed sensitive intermittent wiper device according to the present invention.

FIG. 2 is a diagram showing a rainfall hitting a windshield of an automobile.

FIG. 3 is a diagram illustrating a relationship between a rainfall coefficient and a vehicle speed.

FIG. 4 is a time chart showing the operation of the wiper when the vehicle is stopped and running.

FIG. 5 is a diagram illustrating a relationship between an intermittent pause time and a vehicle speed.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Control unit 2 Microcomputer 10 Wiper switch 11 Intermittent volume 12 Intermittent mode switch 13 Vehicle speed sensor 14 Wiper motor

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-59-137858 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B60S 1/04-1/44

Claims (1)

(57) [Claims] Vector of 1. A vehicle speed sensitive intermittent wiper apparatus with variable intermittent pause time of the wiper in accordance with the vehicle speed, the set value V _R and the horizontal direction of the vehicle speed V _V corresponding to the falling velocity of the vertical raindrop the size of the sum V _B, and means for determining the ratio k of the set value V _R corresponding to the falling velocity of the vertical raindrops, one period T _o + T _W the ratio k of the wiper at the time of vehicle stop
And the operation time T _{W of the} wiper is calculated from the above divided value.
By subtracting, and means for calculating the intermittent pause time T _V of the wiper at the time of running, vehicle speed sensitive type, characterized in that a means for controlling the wiper according to the calculated intermittent pause time T _V Intermittent wiper device.