JPH09150632A - Light blocking device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light blocking device which can apply to a three- dimentionally curved rear window. SOLUTION: This device has a transparent case 14 with a closed space 19, a required amount of electrostatic particles housed in the closed space 19, light blocking electrodes 24, 25 comprising transparent electrodes provided on at least one of a pair of faces opposing in a horizontal direction across the closed space 19 of the transparent case 14, and light transmitting electrodes 27 comprising transparent electrodes provided on the part forming the bottom of the closed space 19 of the transparent case 14. Light is blocked by placing a voltage of antipole to the electrostatic particles 21 across the light blocking electrodes 24, 25 to make the light blocking electrodes 24, 25 absorb the electrostatic particles 21. Light blocking efficiency is reduced by placing a voltage of antipole to the electrostatic particles 21 across the light transmitting electrodes 27 to make the light transmitting electrodes 27 absorb the electrostatic particles 21.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light-shielding device used for a rear window, a sun visor of an automobile, a window of a building, etc., and particularly when these rear windows have a three-dimensional curved surface shape. The present invention also relates to a light-shielding device that can deal with.

[0002]

2. Description of the Related Art Conventionally, as a light-shielding device of this type, as shown in FIG.
A light shielding device as shown in 7 is disclosed. This light-shielding device includes, in a transparent case 1, an electrostatic actuator 5 having a film-shaped stator 2 and a moving member 3, and film-shaped polarizing plates 6A and 6B. These polarizing plates 6A, 6
One polarizing plate 6A of B is fixed to the inner surface of the case 1, and the other polarizing plate 6B is fixed to the mover 3 of the electrostatic actuator 5.

On the stator 2 of the electrostatic actuator 5, three-phase electrodes 7a, 7b, 7c ... 7a, 7b, 7c are formed in a comb shape.
, While the mover 3 is made of a dielectric material and has no electrodes. The electrodes 7a, 7b, 7c ... 7a,
A high voltage is applied to 7b, 7c, ... By periodically switching the polarities, and a suction generated between the voltage applied to the electrodes 7a, 7b, 7c and the voltage generated in the mover 3 by electrostatic induction. The repulsive force causes the mover 3 to move relative to the stator 2 in the directions indicated by arrows X1 and X2 in the figure. This mover 3
The position of the movable side polarizing plate 6B with respect to the fixed side polarizing plate 6A can be adjusted by moving the.

The polarizing plates 6A and 6B have the same structure, and as shown in FIG. 18, a rectangular first polarization plane 8 in which a polarization line a is provided in a horizontal direction on the transparent rectangular film.
And rectangular second polarization planes 9 provided with polarization lines a in the vertical direction in the figure are alternately provided. As shown in FIG. 19, when the first polarization plane 8 and the second polarization plane 9 of the polarizing plates 6A and 6B overlap each other, light is easily transmitted, that is, the light blocking rate is low (the light transmission rate is high. ) State, as shown in FIG. 20, the first polarization plane 8 of the polarization plate 6A and the second polarization plane 9 of the polarization plate 6B are overlapped with each other, and the second polarization plane 9 of the polarization plate 6A and the first polarization plane of the polarization plate 6B are overlapped with each other. The state in which the polarization planes 8 overlap is a state in which it is difficult for light to pass therethrough, that is, a state in which the light blocking rate is high (the light transmittance is low). Therefore, in this light blocking device, the light blocking ratio can be adjusted by driving the electrostatic actuator 5 and adjusting the overlapping amount of the first polarization plane 8 and the second polarization plane 9.

[0005]

However, since the above-mentioned conventional shading device is provided with the film-shaped stator 2, the mover 3 and the polarizing plates 6A and 6B, the window portion has a two-dimensional curved surface shape or a spherical shape. However, it cannot be applied when the shape of the window is a three-dimensional curved surface. That is, in this light-shielding device, it is necessary to slide the film-shaped moving element 3 with respect to the film-shaped stator 2 as described above, but two three-dimensional curved surface-shaped films are superposed in a close contact state. In this case, one film cannot slide with respect to the other film. Therefore, this type of shading device cannot be attached in close contact with a window having a three-dimensional curved surface shape.

Further, if the above-mentioned conventional shading device is forcibly attached to a window having a three-dimensional curved surface, the following problems will occur. That is, when the conventional shading device is attached to the rear window of a three-dimensional car, there is a space (gap) between the shading device and the window glass. The shadow from the light from the player may appear twice.

On the other hand, recently, window glasses having a three-dimensional curved surface shape are sometimes used in the rear windows of automobiles and the like, and therefore, there is an increasing demand for a light-shielding device that can handle such a three-dimensional curved surface shape.

The present invention has been made in order to solve the above problems in the conventional light-shielding device, and an object thereof is to provide a light-shielding device that can be used for a window having a three-dimensional curved surface shape. It was made as.

[0009]

Therefore, according to a first aspect of the present invention, a transparent case having a closed space, a required amount of charged particles housed in the closed space, and a horizontal direction sandwiching the closed space of the transparent case are provided. A light-shielding electrode formed of a transparent electrode provided on at least one of a pair of opposing surfaces, a voltage having a polarity opposite to that of the charged particles is applied to the light-shielding electrode, and the charged particles are applied to the light-shielding electrode. It is intended to provide a light-shielding device characterized in that it is structured such that it is adsorbed and the charged particles are collected on a surface provided with a light-shielding electrode to shield light.

In the light-shielding device according to the first aspect, since the charged particles are adsorbed to the light-shielding electrode provided on the transparent case to prevent the transmission of light, the transparent case can have a three-dimensional curved surface shape. , A three-dimensional curved window or the like can be used.

According to a second aspect of the present invention, a transparent electrode composed of a transparent electrode is provided in a portion of the transparent case forming the bottom of the closed space, and a voltage having a polarity opposite to that of the charged particles is applied to the transparent electrode. The light-shielding device according to claim 1, wherein the light-shielding device is configured to be applied to adsorb the charged particles to the light-transmitting electrode and collect the charged particles at the bottom of the sealed space to reduce the light-shielding rate. It is a thing.

In the light-shielding device according to the second aspect, since the light-transmitting electrode is provided at the bottom of the hermetically sealed space, the charged particles adsorbed to the light-shielding electrode are adsorbed to the light-transmitting electrode to thereby make the hermetically sealed space. The light blocking rate can be reduced by concentrating on the bottom part of the.

The light-shielding electrode may be a plurality of strip-shaped transparent electrodes extending in the horizontal direction and arranged at intervals.
(Claim 3)

In the third aspect, since the light-shielding electrodes are arranged in a transparent case in a striped pattern, light rays can be transmitted to some extent even when the charged particles are adsorbed to the transparent electrode.

The light-shielding electrode has a plurality of strip-shaped transparent electrodes, which extend in the horizontal direction and are spaced apart from each other, on a pair of surfaces facing each other in the horizontal direction across the sealed space of the transparent case. The phase may be shifted so that the transparent electrodes provided on the other surface are located in the gaps between the transparent electrodes provided on the one surface. (Claim 4)

According to the present invention, since the light-shielding electrodes provided on the other surface are located in the gaps between the light-shielding electrodes provided on the one surface, the light-shielding electrodes are shielded by the charged particles. The rate can be almost 100%.

The light-shielding electrode is a two-phase transparent electrode which is a plurality of strip-shaped transparent electrodes extending in the horizontal direction.
A configuration may be adopted in which one of a pair of horizontally facing surfaces of the transparent case is alternately arranged with a gap.
(Claim 5)

According to the present invention, the structure is simple in that the light-shielding electrode is provided only on one of a pair of opposing surfaces of the transparent case which are opposed to each other with the sealed space interposed therebetween.

The light-shielding electrode may be a sheet-shaped transparent electrode provided on one of a pair of horizontally facing surfaces of the transparent case. (Claim 6)

According to the present invention, since the light-shielding electrode is in the form of a sheet, the light-shielding rate when the charged particles are adsorbed to the light-shielding electrode becomes almost 100%.

When a voltage having a polarity opposite to that of the charged particles is applied to the light-shielding electrode, the polarity of the voltage applied to the light-shielding electrode may be periodically switched for a required period.
(Claim 7)

According to the present invention, when the voltage of the opposite polarity to the charged particles is applied to the light shielding electrode as described above, the polarity of the voltage applied to the light shielding electrode is periodically switched for a required period. Therefore, the charged particles are agitated and fluidized to be adsorbed to the light shielding electrode with a uniform thickness.

When a voltage having a polarity opposite to that of the charged particles is applied to the light-transmitting electrode, the polarity of the voltage applied to the light-shielding electrode and / or the light-transmitting electrode is periodically switched for a required period. May be (Claim 8)

In the eighth aspect, when the voltage having the opposite polarity to the charged particles is applied to the light transmitting electrode as described above, it is applied to the light shielding electrode and / or the light transmitting electrode for a required period. Since the polarity of the voltage is periodically switched, the charged particles are agitated and fluidized, and are quickly adsorbed to the light-transmitting electrode.

[0025]

BEST MODE FOR CARRYING OUT THE INVENTION Next, embodiments of the present invention shown in the drawings will be described in detail. A shading device 10 according to a first embodiment of the present invention shown in FIGS. 1 and 2 is a shading device for a rear window 12 of an automobile 11. In the figure, A indicates the outside of the passenger compartment and B indicates the inside of the passenger compartment.

This shading device 10 is shown in FIGS. 2 (A) and 2 (B).
As shown in FIG. 3, a resin transparent case 14 fixed to a glass rear window 12 is provided, and this transparent case 14 covers the entire three-dimensional curved rear window 12.

As shown in FIG. 3, the transparent case 14 is composed of a plate 16 and a cover plate 17, and the plate 16 and the cover plate 17 are the above-mentioned rear window 1.
It has a three-dimensional curved surface shape that closely adheres to 2.

The plate 16 is made of a transparent resin material and is a plate-like member having a three-dimensional curved surface shape that fits the shape of the rear window 12 and having a substantially constant plate thickness.

On the other hand, the cover plate 17 is made of a transparent resin material like the plate 16 and is provided with a main body 17a which is a three-dimensional curved plate-like member conforming to the shape of the rear window 12. On the surface 17b of the main body 17a on the side facing the plate 16 in the horizontal direction, a plurality of vertical walls 18a, 18a, ... Which extend in the vertical direction in FIG. A plurality of lateral walls 18 extending in the left-right direction in FIG. 3 so as to be orthogonal to each other.
A partition wall 18 in the form of a lattice is formed so as to project from b, 18b.

The transparent case 14 is formed by integrally attaching the cover plate 17 to the plate 16, and the surfaces 16a and 17b of the plate 16 and the cover plate 17 which are opposed to each other in the horizontal direction, the vertical wall 18a of the partition wall 18 and The space surrounded by the lateral wall 18b constitutes the closed spaces 19 and 19. In this embodiment, since the partition wall 18 has a lattice shape,
In the transparent case 14, a plurality of closed spaces 19, 19 ... Which are horizontally long and thin and have a rectangular shape are formed in a matrix.

Each closed space 19, 19 ... Stores a required amount of charged particles 21. The charged particles 21
Is a small particle having a negative charge. Therefore, as will be described later, when the electrode has a positive charge, the attracting force acts on the charged particle 21, while when the electrode has a negative voltage, the repulsive force acts on the charged particle 21.

Electrodes are provided on the plate 16 and the cover plate 17. First, the plate 1
As shown in FIGS. 2 (A) and 2 (B), a surface 16 of the plate 16 that faces the sealed space 19 as described above.
a and one of the surfaces 17a of the cover plate 17
6a is provided with the first electrodes 24, 24 ... Which are transparent electrodes that constitute the P1 phase of the light shielding electrode. The P1 phase electrodes 24, 24 ... Are arranged in parallel with each other in a strip shape extending in the horizontal direction. Also, this P1 phase electrode 2
4, 24 ... have a constant width W, and each of the closed spaces 1
It is formed with the same pitch P so that four first electrodes 24 are present in each of 9, 19, .... This pitch P is set to be twice the width W of the electrodes 24.
24. The distance between them is equal to the width W of the electrode 24.

On the other hand, the main body 17 of the cover plate 17
a side facing the cover 16, that is, the partition wall 1
On the surface 17b on the side where 8 is provided, the second electrodes 25, 25 ... Which are transparent electrodes forming the P2 phase of the light shielding electrode are provided. The P2-phase electrodes 25, 25 are strip-shaped extending in the horizontal direction, and are provided on the plate 16 as P1.
Having the same width W as the phase electrodes 24, 24 ... And P1
They are arranged at the same pitch P as the phase electrodes 24. Also,
As shown in FIGS. 2A and 2B, the cover plate 17
Of the P2-phase electrodes 25, 25 ...
.. are arranged so as to be shifted in phase by a width W, and the gaps between the adjacent P1 phase electrodes 24, 24 ... and the P2 phase electrodes 25, 25. The gap between the adjacent P2 phase electrodes 25 and the P1 phase electrode 24
Are facing each other.

Further, in the cover plate 17, the upper surface of the lateral wall 18b of the partition wall 18, that is, the entire surface of the portion forming the bottom wall of the elongated rectangular closed space 19 is a transparent electrode of T phase. The third electrode 27 constituting the above is disposed. The T-phase electrode 27 is in the shape of an elongated strip like the P1-phase electrode 24 and the P2-phase electrode 25, and has a width equal to the amount of protrusion of the partition wall 18 from the main body 17a.

The electrodes 24, 25, 27 are transparent electrodes made of indium-titanium oxide, and have the same translucency as the plate 16 and the cover plate 17.

The P1 phase electrodes 24, 24 ... Are connected to each other, and are connected to the control means 35 via an electric wire 31. Further, the P2 phase electrodes 25, 25 ... Are also connected to each other, and are connected to the control means 35 via the electric wire 32.
Further, the T-phase electrodes 27, 27 ... Are also connected to each other, and are connected to the control means 35 via the electric wire 33. The control means 35 applies a voltage to the electrodes 24, 25, 27 of the P1 phase, P2 phase, and T phase with a desired waveform based on a signal from an operation switch 36 provided in the vehicle compartment.

Next, the operation of the light shielding device of the first embodiment having the above structure will be described. As shown in FIG. 4, from time t ₀ to time t ₁ , the operation switch 36 is “off”.
The voltage applied to the P1 phase electrode 24 and the P2 phase electrode 25 is “0”. On the other hand, a “+” voltage is fixedly applied to the T-phase third electrode 27. In this state, as shown in FIG. 2B, the negatively charged charged particles 21 in each closed space 19 are attracted to the T-phase electrode 27 provided at the bottom. Therefore,
As indicated by an arrow F, light is easily transmitted from the vehicle exterior A to the vehicle interior B, and the light blocking rate is low (high light transmission) (open state).

Next, when the operation switch 36 is set to "ON" at time t ₁ , the voltage applied to the T-phase electrode 27 becomes "0". At this time, the voltage applied to the P1 and P2 phase electrodes 24 and 25 is also "0".
However, this state continues during the (waiting period) of the short required time α. During this waiting period, the charged particles 21
The electrodes 24, 25, and 27 are not attracted to any of them, and can freely move in the closed space 19.

Next, the period from time t ₂ to time t ₃ is
A “+” voltage is fixedly applied to the P1 phase electrode 24 and the P2 phase electrode 25. Therefore, as shown in FIG. 2A, the charged particles 21 in each closed space 19 having a negative charge are attracted to the electrode 24 or the electrode 25. In this state, as shown by the arrow F in the figure, the light beam that is about to pass through the light blocking device 10 is blocked by the charged particles 21 that are adsorbed and collected by the electrodes 24 and 25, so that from the outside A side of the vehicle compartment. The light incident on the vehicle interior B is reduced, and the light shielding rate is high (low light transmittance) (open state).

[0040] If set to "off" the operation switch 36 at time t _3, the P1-phase electrodes 24 and P2 phase electrodes 2
The voltage applied to 5 switches from "+" to "0".
On the other hand, the voltage applied to the T-phase electrode 27 switches from "0" to "+". Therefore, after the time t ₂ described above, P
The charged particles 21 adsorbed on the 1-phase and P2-phase electrodes 24, 25 are separated from these electrodes 24, 25, adsorbed on the T-phase electrode 27, and collected at the bottom of each closed space 19. Therefore, the time t ₃ or later, the open state shown in FIG 2 (B). At time t ₄ after the elapse of the predetermined time β, the voltage applied to the T-phase electrode 27 also becomes “0”.

Thus, the shading device 10 of the first embodiment.
In the configuration, the charged particles 21 housed in each closed space 19 are adsorbed to the electrodes 24, 25 and 27 to adjust the light blocking rate, and the sheet shape is adjusted like the conventional light blocking device shown in FIG. Since it is not necessary to slide the member of
The transparent case 14 can have a three-dimensional curved surface shape, and even with the three-dimensional curved rear window 12, the light blocking rate can be adjusted by switching the operation switch 36.

FIG. 5 shows a second embodiment of the present invention. The second embodiment has a configuration in which the second electrodes 25, 25, ... Which constitute the P2 phase in the first embodiment are eliminated.
That is, the surface 16a of the plate 16 and the surface 16a of the plate 16 of the surface 17a of the cover plate 17 which are opposed to each other in the horizontal direction with the hermetically-sealed space therebetween have a strip shape extending in the horizontal direction and constitute a P1 phase. First electrodes 24, 24 ...
Are provided at equal intervals. In addition, the cover plate 17
The third electrode 27 constituting the T phase having the same width as the protruding amount of the partition wall 18 is provided on the entire upper surface of the lateral wall 18b of the partition wall 18 forming the bottom of the closed space 19. Since the other structure of the second embodiment is similar to that of the first embodiment, the same elements are designated by the same reference numerals and the description thereof will be omitted.

Next, the operation of the second embodiment will be described. As shown in FIG. 6, from time t ₀ to time t ₁ , the operation switch 36 is set to “OFF”, and P
The voltage applied to the one-phase electrode 24 is “0”. On the other hand, a “+” voltage is fixedly applied to the T-phase electrode 27. In this state, as shown in FIG.
Since the charged particles 21 in each closed space 19 are adsorbed and concentrated on the T-phase electrode 27 arranged at the bottom of each closed space 19, as shown by the arrow F, light is easily transmitted and shielded. Low open rate.

Next, after the operation switch 36 is set to "ON" at time t ₁ , the electrodes 24 and 27 are turned on during the waiting period α.
The voltage applied to the both becomes "0", and the charged particles 21 are not attracted to any of the electrodes 24 and 27, and can move freely in the closed space 19.

Next, the period from time t ₂ to time t ₃ is
A "+" voltage is fixedly applied to the P1 phase electrode 24,
The voltage applied to the T-phase electrode 27 is “0”. Therefore, as shown in FIG. 5 (A), the charged particles 21 in each closed space 19 are adsorbed by the electrode 24 of the P1 phase, so that the charged particles 21 are incident from the outside A of the vehicle compartment as indicated by an arrow F in the figure. The light beam is adsorbed and collected on the P1 phase electrode 24.
Since it is blocked by 1, the closed state has a high light blocking rate.
However, in the second embodiment, as described above, the plate 16
Since the electrodes are not provided on the cover plate 17 side so as to face the gaps between the electrodes 24, 24 disposed on the cover 24, the light blocking rate in the closed state is about half that in the first embodiment.

[0046] If set to "off" the operation switch 36 at time t _3, the voltage applied to the electrodes 24 of the P1-phase switches from "0" to "+". On the other hand, the T-phase electrode 27
The voltage applied to is switched from "0" to "+".
Therefore, the time t ₂ after the charged particles 21 that has been adsorbed on the electrode 24 of P1 phase, away from the electrode 24, is attracted to the electrode 27 of the T-phase, gathered in the bottom of each sealed space 19,
The open state as shown in FIG. At time t ₄ after the time β has elapsed, the voltage applied to the T-phase electrode 27 also becomes “0”.

Since the shading device 10 of the second embodiment is also configured to adsorb the charged particles 21 in the closed space 19 to the electrodes 24 and 27 as in the case of the first embodiment, the shading rate is adjusted. The transparent case 14 can have a three-dimensional curved surface shape, and even with the three-dimensional curved rear window 12, the light blocking rate can be adjusted by turning on / off the operation switch 36. Further, as described above, since the P2 phase electrode 25 on the cover plate 17 side is omitted, the structure is simple as compared with the first embodiment.

FIG. 7 shows a third embodiment of the present invention. In the third embodiment, the plate 16 has an equal pitch,
The electrodes 24, 25, ... Which are arranged at equal intervals are connected to each other by the electrodes 24, 25, which are arranged every other electrode, and are respectively connected to P1.
Phase and P2 phase. Also, the cover plate 17 is
T-phase electrodes 27, 27 provided at the bottom of the closed space 19
.. only, and no electrode is provided on the main body 17a of the cover plate 17. The other structure of the third embodiment is the same as that of the above-described first embodiment. In the light shielding device of the third embodiment, the P1 phase, P2 phase and T phase electrodes 24, 25 having the same waveforms as those of the first embodiment shown in FIG.
By applying a voltage to 27, the light blocking rate can be adjusted.

8 and 9 show a fourth embodiment of the present invention. In the light shielding device according to the fourth embodiment, the surface 16 of the plate 16 facing the cover plate 17 is provided.
An electrode 40, which has a sheet shape substantially the same as the plate 16 and constitutes the P1 phase, is attached to a. Also,
The surface of the electrode 40 is also covered with a sheet-shaped insulating thin film 41.

On the other hand, the cover plate 17 is shown in FIG.
As shown in (A) and (B), a grid-like electrode 42 forming the T phase is provided. That is, the surfaces of the vertical walls 18 a and the horizontal walls 18 b of the partition wall 18 are covered with the electrodes 42 so that the entire circumference of each closed space 19 is surrounded by the electrodes 42. The electrodes 42 surrounding the closed spaces 19 are connected to each other.

The electrode 40 on the plate 16 side and the electrode 42 on the cover plate 17 side are connected to the control means 35, respectively, and a waveform voltage is applied to the electrodes 40, 42 as shown in FIG. By applying voltage respectively,
Adjust the shading rate.

First, a voltage of "+" is applied to the grid-shaped T-phase electrode 42 on the cover plate 17 side to plate 1
When a voltage of “0” is applied to the sheet-shaped P1 phase electrode 40 on the 6 side, the charged particles 21 are charged into the T phase electrode 42 as shown in FIGS. 8 (A) and 9 (B). Are attracted to and are collected on the surface of the partition wall 18. Therefore, as shown by an arrow F in FIG. 9B, the light beam is in an open state where it passes without being blocked by the charged particles 21.

On the other hand, when a voltage of "+" is applied to the sheet-shaped electrode 40 on the plate 16 side and the voltage of the grid-shaped electrode 41 on the cover plate 17 side is set to "0", FIG. As shown in B), the charged particles 2 in each closed space 19
No. 1 is attached to the plate 16 side, and as shown by an arrow F in the figure, a light ray incident from the outside A of the vehicle compartment is blocked by the charged particles 21, and the light blocking rate is close to 100%.

In the first to fourth embodiments, the waveform applied to the electrodes is not limited to the above.
For example, the first embodiment shown in FIGS. 1 to 3 and FIG.
In the third embodiment shown in FIG. 10, a voltage may be applied as shown in FIGS.

For example, in FIG. 10, as in the case of FIG. 4, the electrodes of the P1 phase and the P2 phase are started from time t ₂ after a required time α has elapsed since the operation switch 36 was set to “ON” at time t _1. Charged particles 2 by applying a "+" voltage to 24 and 25
1 at these electrodes 24, 25, but at time t ₂
From the time t ₂ 'to the electrode 2 for both P1 phase and P2 phase
"+" And "0" are alternately repeated in the time width γ for the voltage applied to 4, 25. The phases of the P1 phase and the P2 phase are set to be offset by the time width γ, and if one of the P1 phase electrode 24 and the P2 phase electrode 25 is “+”, the other is “−”. ". As described above, when the operation switch 36 is switched from “OFF” to “ON”, that is, when the light shielding device 10 is switched from the open state to the closed state, the electrodes 24 and 25 which are the light shielding electrodes.
When a pulse-like “+” and “0” are repeatedly applied to, the attraction force intermittently acts on the charged particles 21 in each closed space 19, so that the charged particles 21 are stirred and flow. However, the time t ₂ later, in the state in which fixedly high voltage to the electrodes 24, 25 is applied, becomes uniform thickness of the charged particles 21 adsorbed on the electrodes 24 and 25 located on each closed space 19, The distribution of the light blocking rate becomes uniform in the entire light blocking device 10. The application of the voltage shown in FIG. 10 is the same as the case shown in FIG. 4 in other points.

FIG. 11 shows that in FIG. 10, the voltage applied to the electrodes 24 and 25 in both P1 phase and P2 phase as described above is “+” in the time width γ from the time t ₂ to the time t ₂ ′. And "0" are alternately repeated, and "-" and "0" are alternately and repeatedly applied to the T-phase electrode with a time width γ.

In this case, between the time t ₂ and the time t ₂ ′, the charged particle 21 has a P1 phase electrode 24 and a P2 phase electrode 25.
The suction force acts intermittently from the T-phase electrode 27.
The repulsive force acts intermittently from. Therefore, the charged particles 12
Is agitated more violently, and after the time t ₃ , the electrodes 24 and 25 are
In the state where a high voltage is fixedly applied to the electrodes, the thickness of the charged particles 21 adsorbed to the electrodes 24 and 25 located in the individual closed spaces 19 becomes more uniform, and the light blocking ratio becomes higher in the entire light blocking device 10. Become even.

10 and 11, in the first embodiment, when the operation switch 36 is switched from "ON" to "OFF", that is, before the shading device 10 is changed from the open state to the closed state, the charged particles 21 are discharged. 12 to 13, the charged particles 21 are also fluidized when the operation switch 36 is switched from “OFF” to “ON”, that is, when the closed state is switched to the open state. .

First, in FIG. 12, similar to FIG. 11,
When the operation switch 36 at time t ₁ is set to "on", from time t ₂ to time t ₂ ', with "0" and "+" for P1 phase, P2-phase electrodes 24, 25 The voltage is applied by switching the polarity, and the voltage is applied to the T-phase electrode 27 by switching the polarity between “0” and “−”. Also,
After the operation switch 36 at time t ₃ is set to "off", between times t ₄ ', it applies a voltage by switching the polarity of the electrode 25 of P1-phase electrodes 24 and P2 phase. I sanded, during the period from the time t ₃ to time t ₄ ', it is switching between "0" and "-1/2" the voltage at the time width γ.
Here, "-1/2" means 1/2 of "-" as described above.
It indicates that the voltage value is. In addition, the T-phase electrode 2
For 7, as in the case of FIG 11, after the operation switch 36 at time t ₃ is set to "off", fixedly voltage up to time t ₄ after a predetermined time gamma "+" A voltage is applied and then set to "0".

When a voltage is applied as shown in FIG. 12,
Before switching from the closed state to the open state, the polarity is periodically switched to the P1 phase electrode 24 and the P2 phase electrode 25 to apply a voltage, so that the repulsive force is intermittently applied to the charged particles 21. It acts and the electrification current 21 is fluidized. Therefore,
After the time t ₄ ′, the charged particles 21 do not remain on the electrodes 24 and 25, and surely gather at the bottom of each closed space 19 to obtain the desired translucency.

FIG. 13 shows the P1 phase electrode 24 and the P2 phase electrode 25 between time t ₂ and time t ₂ ′, which is performed when the operation switch 36 is set from “OFF” to “ON” in FIG. In contrast, the time width γ is “+” and “+1/2”
The polarity is changed over to apply a voltage. Other points of FIG. 13 are similar to those of FIG.

In the case of FIG. 13, the polarity is switched between the electrodes 24 and 25 of the P1 phase and the P2 phase to apply the voltage between the time t ₂ and the time t ₂ ′.
Fluidizes. In addition, since the voltage applied to the electrodes 24 and 25 of the P1 phase and the P2 phase does not become “0” also from the time t ₂ to the time t ₂ ′, the charged particle 21 electrode once attracted to the electrodes 24 and 25. Since it pulsates while being adsorbed on 24 and 25, it is possible to change from the open state to the closed state more quickly and reliably.

On the other hand, in the second embodiment shown in FIG. 5 and the fourth embodiment shown in FIG. 8, a voltage is applied to the P1 phase electrode 24 and the T phase electrode 27 with the waveforms shown in FIGS. You may apply. First, in FIG. 14, the period from time t ₂ to time t ₂ 'after the required time α is set as the operation switch 36 is "on" at time t _1, switch the polarity to the electrodes 24 of the P1-phase Apply voltage. That is, from time t ₂ to time t ₂ ′, the voltages “0” and “+” are alternately applied to the electrode 24 of the P1 phase with the time width γ. Therefore, in the case of FIG. 13, similarly to the case of FIG. 10 described above, the charged particles 2 are kept from the time t ₂ to the time t ₂ ′.
The fluid is fluidized because the suction force is intermittently applied to 1 to be stirred, and after time t ₂ ′, if a voltage of “+” polarity is fixedly applied to the electrode 24, each sealed space 19 The thickness of the charged particles 21 adsorbed on each of the electrodes 24 becomes uniform,
The distribution of the light blocking ratio of the light blocking device is made uniform. Other points of FIG. 14 are similar to those of FIG.

FIG. 15 shows that, between the time t ₂ and the time t ₂ ′ shown in FIG. 14, the polarity is set to “0” and “−1/2” for the T-phase electrode 27 with a time width γ. Switch to apply voltage. Further, in FIG. 15, after the operation switch 36 at time t ₃ is set to "off", the period until time t ₄ when the voltage of "+" to the electrode 27 of the T-phase is fixedly applied, A voltage is applied to the P1 phase electrode 24 by switching the polarity.

That is, in FIG. 15, from time t ₃ to time t ₄ , the voltages "0" and "-1/2" are alternately applied to the electrode 24 of the P1 phase with the time width γ. FIG.
When a voltage is applied as, while after setting to "off" the operation switch 36 until time t _4, the charged particles 2
The repulsive force acts intermittently on 1 and the charged particles 21 are fluidized in the closed space 19. Therefore, when the voltage is applied as shown in FIG. 15, after the operation switch 36 is set to “OFF”, the charged particles 21 do not remain on the P1 phase electrode 24, and in the open state, the required transparency is obtained. The luminous efficiency is surely obtained.

[0066] Figure 16, in FIG 15, after setting the operation switch 36 to "on" at time t _1, at a predetermined time width γ between the time t ₂ to time t ₂ 'and "0"" -1
The voltage is switched by 1/2 ". Therefore, when switching from the open state to the closed state, the charged particles 21 once attracted to the electrode 24 are retained in the state of being attracted to the electrode 24, so that the charged particles 21 are closed more quickly and reliably. 16 can be switched to the state, and the other points of FIG.

The present invention is not limited to the above embodiment, but various modifications can be made. For example, the light-shielding device of the above-described embodiment is for a rear window of an automobile, but the present invention is not limited to this, and can be applied to a sun visor of automobiles, a side window, a window of a building, or the like.

Further, it goes without saying that the light shielding device of the present invention is not limited to the window having the three-dimensional curved surface shape as in the above-mentioned embodiment, but can be applied to the window having the flat surface, the two-dimensional curved surface shape and the spherical curved surface shape. Nor.

[0069]

As is apparent from the above description, in the light-shielding device according to the first aspect, the light-shielding electrode provided on the transparent case adsorbs the charged particles to improve the light-shielding rate. Since it does not have a structure in which a sheet-like member slides like a light-shielding device, the transparent case can have a three-dimensional curved surface shape. Therefore, this shading device can be used for a window having a three-dimensional curved surface shape.

In the light-shielding device of the second aspect, since the light-transmitting electrode is provided at the bottom of the hermetically sealed space, the charged particles adsorbed to the light-shielding electrode are adsorbed to the light-transmitting electrode so that the bottom of the hermetically sealed space is absorbed. It is possible to reduce the light blocking rate by concentrating the light on the screen. Therefore, when the light-transmitting electrode is provided, the light-shielding rate can be switched between a closed state where the light-shielding electrode adsorbs the charged particles and a closed state where the light-transmitting device adsorbs the charged particles.

When the light-shielding electrodes are a plurality of strip-shaped transparent electrodes extending in the horizontal direction and arranged at intervals as in the third aspect, the light-shielding electrodes are arranged in a stripe shape in a transparent case. Since it is provided, the light beam can be transmitted to some extent even in the state where the charged particles are adsorbed on the transparent electrode.

According to a fourth aspect of the present invention, a plurality of strip-shaped transparent electrodes extending in the horizontal direction are arranged at intervals on a pair of horizontally facing surfaces of the transparent case that sandwich the closed space. In addition, when the light-shielding electrodes are formed by arranging the transparent electrodes provided on the other surface so that the transparent electrodes provided on the other surface are positioned in the gaps between the transparent electrodes provided on the one surface, When the charged particles are adsorbed on the working electrode, the light blocking rate can be made almost 100%.

When the light-shielding electrode is provided on only one surface of a pair of opposing surfaces of the transparent case which face each other with the closed space containing the charged particles interposed therebetween, the structure is Is simple and the manufacturing cost can be reduced.

When the light-shielding electrode is in the form of a sheet as in claim 6, the light-shielding rate when the charged particles are adsorbed to the light-shielding electrode is almost 100%.

As described in claim 7, when the voltage of the opposite polarity to the charged particles is applied to the light-shielding electrode, the polarity of the voltage applied to the light-shielding electrode is periodically switched for a required period. In this case, the charged particles are agitated and fluidized, and the charged particles are adsorbed to the light-shielding electrode with a uniform thickness, so that the distribution of the light-shielding ratio in the entire light-shielding device can be made uniform.

When a voltage having a polarity opposite to that of the charged particles is applied to the light-transmitting electrode as in claim 8, the polarity of the voltage applied to the light-shielding electrode and / or the light-transmitting electrode for a required period. In the case where the configuration is switched periodically, the charged particles separated from the light-shielding electrode are agitated and fluidized, and are quickly adsorbed to the light-transmitting electrode, so that switching from the closed state to the open state is performed. It can be done quickly and reliably.

[Brief description of the drawings]

FIG. 1 is a perspective view of an automobile equipped with a light shielding device according to the present invention in a rear window.

FIG. 2 shows the light shielding device according to the first embodiment, (A)
Is a schematic cross-sectional view taken along line II-II of FIG.
FIG. 2B is a schematic sectional view taken along line II-II in FIG. 1 showing a translucent state.

FIG. 3 is an exploded perspective view of a transparent case of the light shielding device according to the first embodiment.

FIG. 4 is a waveform diagram showing a voltage applied to the electrodes of the light shielding device according to the first embodiment.

FIG. 5 shows a light shielding device according to a second embodiment, (A)
Is a schematic cross-sectional view showing a light-shielding state, and (B) is a schematic cross-sectional view showing a light-transmitting state.

FIG. 6 is a waveform diagram showing a voltage applied to an electrode of the light shielding device according to the second embodiment.

FIG. 7 shows a light shielding device according to a third embodiment, (A)
Is a schematic cross-sectional view showing a light-shielding state, and (B) is a schematic cross-sectional view showing a light-transmitting state.

FIG. 8 shows a light shielding device according to a fourth embodiment, (A)
Is a schematic cross-sectional view showing a light-shielding state, and (B) is a schematic cross-sectional view showing a light-transmitting state.

9A and 9B show a transparent case of a light shielding device according to a fourth embodiment, where FIG. 9A is a partially exploded perspective view and FIG. 9B is an arrow of FIG.
It is the elements on larger scale seen from IX.

FIG. 10 is a waveform diagram showing another example of the voltage applied to the electrodes of the light shielding device according to the first embodiment.

FIG. 11 is a waveform diagram showing another example of the voltage applied to the electrodes of the light shielding device according to the first embodiment.

FIG. 12 is a waveform diagram showing another example of the voltage applied to the electrodes of the light shielding device according to the first embodiment.

FIG. 13 is a waveform diagram showing another example of the voltage applied to the electrodes of the light shielding device according to the first embodiment.

FIG. 14 is a waveform diagram showing another example of the voltage applied to the electrodes of the light shielding device according to the second embodiment.

FIG. 15 is a waveform diagram showing another example of the voltage applied to the electrode of the light shielding device according to the second embodiment.

FIG. 16 is a waveform diagram showing another example of the voltage applied to the electrode of the light shielding device according to the second embodiment.

FIG. 17 is a partial cross-sectional view showing an example of a conventional light shielding device.

18 is a plan view showing a polarizing plate of the light shielding device of FIG.

19 is a plan view showing a transparent state of the light shielding device of FIG.

20 is a plan view showing a light shielding state of the light shielding device of FIG.

[Explanation of symbols]

 12 Rear window 14 Transparent case 16 Plate 17 Cover plate 18 Partition wall 19 Closed chamber 21 Charged particles 24, 25, 27, 40, 42 Electrode 35 Control means 36 Operation switch

Claims (8)

[Claims] 1. A transparent case having a hermetically sealed space, a required amount of charged particles contained in the hermetically sealed space, and at least one of a pair of horizontally facing surfaces sandwiching the hermetically sealed space of the transparent case. A light-shielding electrode made of a transparent electrode is provided, and a voltage having a polarity opposite to that of the charged particles is applied to the light-shielding electrode so that the charged particles are adsorbed to the light-shielding electrode, and the light-shielding electrode is provided with A light-shielding device having a structure in which charged particles are collected to shield light. 2. A transparent electrode, which is a transparent electrode, is provided in a portion of the transparent case that forms a bottom portion of the closed space,
A voltage having a polarity opposite to that of the charged particles is applied to the transparent electrode,
2. The shading device according to claim 1, wherein the charged particles are adsorbed to the light-transmitting electrode, and the charged particles are collected at the bottom of the closed space to reduce the light blocking rate. 3. The light-shielding device according to claim 1, wherein the light-shielding electrode is a plurality of strip-shaped transparent electrodes extending in the horizontal direction and arranged at intervals. 4. The light-shielding electrode has a plurality of strip-shaped transparent electrodes extending in the horizontal direction and arranged at intervals on a pair of surfaces facing each other in the horizontal direction with the sealed space of the transparent case interposed therebetween. The phase shifter is provided so that the transparent electrodes provided on the other surface are located in the gap between the transparent electrodes provided on the one surface.
Alternatively, the light shielding device according to claim 2. 5. The light-shielding electrode comprises a plurality of strip-shaped transparent electrodes extending in the horizontal direction, which are two-phase transparent electrodes, and are provided on one of a pair of horizontally facing surfaces of the transparent case. The light-shielding device according to claim 1 or 2, wherein the light-shielding devices are arranged alternately at an opening. 6. The light-shielding electrode is a sheet-shaped transparent electrode disposed on one of a pair of surfaces of the transparent case that are opposed to each other in the horizontal direction, and is a sheet-shaped transparent electrode.
The light-shielding device according to. 7. A structure in which, when a voltage having a polarity opposite to that of the charged particles is applied to the light-shielding electrode, the polarity of the voltage applied to the light-shielding electrode is periodically switched for a required period. The shading device according to any one of claims 1 to 6. 8. A light-shielding electrode and / or a light-shielding electrode for a required period when a voltage having a polarity opposite to that of charged particles is applied to the light-transmitting electrode.
Alternatively, the polarity of the voltage applied to the translucent electrode is periodically switched, and the shading device according to any one of claims 2 to 7.