JPH05262204A - Cloud remover - Google Patents

Abstract

PURPOSE:To provide a cloud detecting remover of wide applicable range by utilizing an ultrasonic wave. CONSTITUTION:An ultrasonic wave transmitter 10 provided in a right lower edge part in a surface of glass 100 to transmit a surface wave propagated on the surface, driving power source 20 of vibration-exciting this ultrasonic wave transmitter by a high frequency of ultrasonic wave region and capable of adjusting this vibratory excitation energy and an ultrasonic wave receiver 30 for receiving the surface wave propagated on the glass surface are provided to detect a cloud of the glass surface through surface wave attenuation detection by this ultrasonic wave receiver, and by increasing vibratory excitation energy by the driving power source 20, water drips on the surface of the glass 100 are scattered and removed by the surface wave.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a defrosting device for window glass of vehicles and the like.

[0002]

2. Description of the Related Art As a conventional technique for removing fogging on window glass of a vehicle or the like, there are a method of blowing warm air to a glass surface using an air conditioning duct in a vehicle, a method of introducing outside air, and the like.
As for the rear window, a structure is adopted in which water is removed by energizing the glass on which heat rays are arranged.

[0003]

The above-mentioned conventional method for removing fogging has the following drawbacks. (A) In the case of a method of sending warm air to the glass surface Comfort of the vehicle interior by air conditioning is impaired by hot and cold air.

When exposed to cold outside air to cause severe fogging, and when quick defoaming is required, the temperature of warm air is low and it takes a long time to remove the fogging.

It is difficult to apply a sufficient amount of warm air to the window portion that needs to be particularly defrosted. (B) In case of removing fogging by heat rays It is necessary to use a special glass window containing heat rays.

[0006] The field of view is obstructed by the heat rays.

[0007]

The present invention takes the following means in order to solve the above problems. (1) An ultrasonic wave transmitting means which is provided at an edge portion of the surface of the glass body and transmits a surface wave propagating on the surface of the glass body, and a driving power supply which vibrates the ultrasonic wave transmitting means at a high frequency in an ultrasonic range. And a defrosting device for a glass body, wherein the surface wave is used to scatter and remove water drops on the surface of the glass body. (2) An ultrasonic wave transmitting unit that is provided at the edge of the surface of the glass body and transmits a surface wave that propagates on the surface of the glass body, and the ultrasonic wave transmitting unit is vibrated at a high frequency in the ultrasonic range, and
The driving power source capable of adjusting the excitation energy and ultrasonic wave receiving means for receiving a surface wave propagating on the glass body surface are provided, and the surface wave attenuation is detected by the ultrasonic wave receiving means to fog the surface of the glass body. To detect and remove the water droplets on the surface of the glass body by the surface waves to increase the excitation energy of the drive power source. (3) The fogging detection / removal device for a glass body according to the item (2), wherein a reflector is installed in the surface wave propagation path between the ultrasonic wave transmitting means and the ultrasonic wave receiving means.

[0008]

[Action]

(1) In the above means, when ultrasonic waves are generated by the ultrasonic wave transmitting means, the surface of the glass body (elastic body such as glass or plastics) vibrates by the surface acoustic waves of ultrasonic vibration. Therefore, the water particles on the surface are vibrated and scattered, and the cloudiness is removed.

In this way, the glass body can be easily defrosted. (2) In the above means, the ultrasonic wave transmitting means is driven from the drive power source with a predetermined power. Then, the surface of the glass body becomes a surface acoustic wave of ultrasonic vibration and reaches the ultrasonic wave receiving means.
The ultrasonic wave receiving means receives the incident surface acoustic wave, detects the attenuation of the surface wave from the level thereof, and detects the fogging on the surface of the glass body.

When the fog on the surface of the glass body is detected, the ultrasonic wave transmitting means is driven from the driving power source with electric power larger than the predetermined electric power. Then, the same action as in (1) above is performed, and the haze of the glass body is removed. In this way, the fogging of the glass body can be easily detected and removed. (3) In the above means, the surface acoustic wave from the ultrasonic wave transmitting means propagates through the glass body, is reflected by the reflector, and then propagates through the glass body again to reach the ultrasonic wave receiving means. Therefore, when the reflector is provided at an appropriate position, a wider area on the surface of the glass body becomes the surface wave propagation path.

Others operate in the same manner as (2) above.

[0012]

Since the inventions of claims 1 and 2 can be easily understood and implemented from the invention of claim 3, one embodiment of the invention of claim 3 will be described with reference to FIGS.

Referring to FIG. 1, a windshield 100 of a passenger car.
The ultrasonic transmitter 10 is provided on the right side of the lower edge. The ultrasonic transmitter 10 is connected to a drive power source 20 with variable output. Further, a reflector 40 is provided at the center of the upper edge of the windshield 100. Further, the ultrasonic receiver 30 is provided on the lower left portion of the windshield 100.

The details of the transmitter 10 and the receiver 30 are shown in FIG.

A vibrator 12 having a vibration transmitting member 11 is arranged on the surface of the windshield 100 at a predetermined inclination, and the vibration transmitting member 11 is bonded with an adhesive 13. These are transmitters 10. The vibrator 12 is connected to the driving power supply 20.

A detection element 32 having a vibration transmission member 31
Are arranged on the surface of the windshield 100 with a predetermined inclination, and the vibration transmitting member 31 is adhered by the adhesive material 33. The detection element 32 is connected to the amplifier 34. These are receivers 3
It becomes 0.

As the vibrator 12 and the detection element 32, an electrostrictive element, a magnetostrictive element, etc., an electrostrictive element, a coil detector, etc. are used.

In the above, the drive power source 20 is the DC power source E.
Is a biased AC power supply in which an AC power supply Vo with variable amplitude is connected in series, and outputs a biased AC voltage v _o (see FIG. 6) of a frequency f (a simple AC power supply that does not have the DC power supply E according to the characteristics of the vibrator). May be). When this AC voltage is applied stepwise, the vibrator 12 causes mechanical strain and vibrates the vibration transmitting member 11 by its acceleration. This exciting force becomes an elastic wave of a longitudinal wave and propagates in the vibration transmitting member 11. The propagation velocity c ₂ is given by the equation (1) as a first approximation.

C ₂ = √ (E ₂ / ρ ₂ ) (1) where ρ _{2 is} the density of the transmitting member E ₂ is the Young's modulus of the transmitting member This vibration is transmitted to the glass 100 and becomes a surface wave. Propagate. The propagation velocity c is given by the equation (2) as a first approximation.

C = 0.92√ (G / ρ) (2) where ρ: density of glass G: lateral elastic modulus of glass At this time, the vibration transmission member 11 is against the surface of the glass 100. The vibration is more efficiently transmitted as a surface wave when the device is mounted at an angle of θ represented by the following formula (5).

This relationship will be described below. Let the thickness of the vibration transmission member 11 be r, and consider a wavefront perpendicular to the plate thickness. Figure 4
As shown in, when the wavefront when the vibration of the member 11 reaches the surface of the glass 100 is ab, the wave at the point a propagates to the glass 100 at this point and propagates at a velocity c. After that, the wave at point b is delayed by time t and the glass 10
A surface d of 0 is reached.

The required time t, ad of the wave propagating through bd now
If t = t 'is set as the required time t'of the wave propagating, the vibration of the member 11 will be transmitted to the glass 100 more efficiently. (The phase of the surface wave starting from point a and the phase of the wave at point d are in phase, and the wave phenomenon intensifies.) Therefore, t = bd / c ₂ = cot θ · r / c ₂ ……… (3) t ′ = ad / C = (r / sin θ) · (1 / c) ... (4) Equation (5) is obtained.

Θ = cos ⁻¹ (c ₂ / c) (5) When a predetermined ultrasonic burst signal is input to the transmitter 10 from the power supply 20, the inner surface of the windshield 100 is directed toward the reflection plate 40. The surface acoustic wave of the ultrasonic wave propagates toward ((A direction in FIG. 1)). This surface wave is reflected by the reflector 40 and propagates toward the receiver 30 (arrow B). The surface wave is received by the receiver 30. That is, the surface acoustic wave reaches the detector 32 via the transmission member 31, is converted into an electric signal by the detector 32, and is amplified and detected by the amplifier 34.

The sensitivity of the detector 32 is maximized when each inclination θ '(see FIG. 5) satisfies the equation (6), as in the case of the oscillator.

Θ ′ = cos ⁻¹ (c ₃ / c) (6) where, c ₃ is the propagation velocity in the transmission member 31 and the output of the receiver 30 attenuates the propagation path of the windshield 100. Is detected.

This attenuation is mainly due to the leakage of surface acoustic waves to the water particles adhering to the surface of the windshield 100, causing a flow in the water particles. That is, as shown in FIG. 3, the surface acoustic wave 50 is hardly attenuated on the interface with the atmosphere 60. However, at the interface with the water particles 70, there is wave propagation from the solid to the liquid, the vibration velocity decreases with the progress of the surface wave, and the vibration velocity has a spatial gradient, so that a specific angular direction A unidirectional flow to (arrow f) occurs. Therefore, the surface wave 50 is greatly attenuated.

Although the attenuation of each water particle 70 is small, the reduction of the surface wave propagation surface as a whole is clearly different depending on the presence or absence of water particles. Therefore, the presence or absence of fog is detected based on the level of the received wave in the dry state.

When the fog on the windshield 100 is detected, the output of the power supply 20 is increased. Then, the amplitude of the surface wave 50 increases and the vibration in the water particle 70 increases.
Therefore, the interfacial force between the water and the glass surface is broken, the water is scattered, and the cloudiness is removed (see FIG. 3).

In this way, the fog on the windshield 100 is detected and easily removed. Further, the surface wave is reflected by the reflector 40, so that the windshield 10
A wide range on 0 can be propagated. In other words, a transmitter with a narrow output aperture can remove a wide range of fog.

In the above, the reflector 40 and the receiver 30 are used, but the reflector 40 may not be used and the direct wave may be received. Alternatively, the cloudiness may be visually detected without using the receiver.

[0031]

As described above, the present invention has the following effects. Since it is possible to detect and remove fogging without obstructing the field of view of the glass body (window glass), it is possible to drive safely without imposing a burden on the driver of the vehicle. Since cloudiness detection and removal are performed independently of air conditioning,
You can always set comfortable air conditioning conditions. The object to which the defrosting device is applied is not a special glass body, but curved glass that is generally used on the front, rear, sides, etc. of vehicles. Since surface acoustic waves are used, it is possible to detect and remove fogging with high reliability without being affected by the external environment.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an embodiment of the invention of claim 3;

FIG. 2 is a detailed configuration diagram of a transmitter and a receiver section of the embodiment.

FIG. 3 is an explanatory view of the operation of the embodiment.

FIG. 4 is an explanatory view of the operation of the embodiment.

FIG. 5 is an explanatory view of the operation of the embodiment.

FIG. 6 is an explanatory view of the operation of the embodiment.

[Explanation of symbols]

 100 Windshield 10 Surface acoustic wave transmitter 40 Reflector 30 Surface acoustic wave receiver A, B Surface acoustic wave traveling direction 70 Water particle 60 Atmosphere 50 Surface acoustic wave toward water particle f Direction of water flow 20 Driving power source

Claims (3)

[Claims] 1. An ultrasonic wave transmitting means, which is provided at an edge portion of the surface of the glass body and transmits a surface wave propagating on the surface of the glass body, and the ultrasonic wave transmitting means is vibrated at a high frequency in an ultrasonic range. A defogging device for a glass body, comprising: a drive power source, and scattering and removing water droplets on the surface of the glass body by the surface wave. 2. An ultrasonic wave transmitting means which is provided at an edge portion of the surface of the glass body and which transmits a surface wave propagating on the surface of the glass body, and the ultrasonic wave transmitting means is vibrated at a high frequency in an ultrasonic range. Along with this, a driving power source capable of adjusting the excitation energy and an ultrasonic wave receiving means for receiving a surface wave propagating on the glass body surface are provided, and the glass body surface is detected by the surface wave attenuation detection by the ultrasonic wave receiving means. Is detected and the vibration energy by the drive power source is increased to scatter and remove water drops on the surface of the glass body by the surface waves. 3. The fogging detection removing device for a glass body according to claim 2, wherein a reflector is installed in the surface wave propagation path between the ultrasonic wave transmitting means and the ultrasonic wave receiving means.