JPS646496Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] The present invention relates to an anti-glare mirror for a vehicle, and more specifically, the reflectance of the mirror is varied depending on the brightness of headlight light emitted by a following vehicle, The present invention relates to a drive circuit for an anti-glare mirror that performs anti-glare.

[Conventional technology]

Conventional anti-glare mirrors for vehicles use a liquid crystal panel on the mirror surface, and a light sensor is attached to a part of the mirror housing.When strong light from a following vehicle is detected, the mirror surface becomes a low-reflection mirror. There are known devices that control voltage application (or voltage application cut-off) to improve the rate.

Furthermore, a configuration as shown in FIG. 3 is also known. Figure 3 shows a configuration that switches between anti-glare and non-dimming. In the figure, BT is a battery, CVC is a constant voltage circuit, EC is an electrochromism, A/1 is a relay with contact a, _SW1 ,
SW ₂ is a changeover switch. The same configuration is a switch
When SW ₁ is open, the mirror is used as one with high reflectivity. Then, switch SW ₁ is closed and electrochromism EC is connected via constant voltage circuit CVC.
By driving the mirror, the reflectance of the mirror is made low. That is, normally, electrochromism EC is in a short-circuited state due to contact a of relay A/1, and contact a is switched by closing switch SW ₂ , and voltage is applied to electrochromism EC via constant voltage circuit CVC. This is applied to cause the mirror surface to have an anti-glare action, so-called low reflectance.

[Problem that the invention attempts to solve]

However, in such an anti-glare mirror drive circuit that utilizes electrochromism (hereinafter referred to as EC), when switch SW ₁ is opened and the battery power is turned off, EC is in a short-circuited state. , by turning on switch SW ₁ and turning on switch SW ₂ , the switch is switched from non-dimming to dimming, and switching between the ground level and a positive DC voltage at a certain value Therefore, when the battery power is turned off, the memory characteristic of EC disappears, and when the power is turned on,
A drawback of EC is that it takes time to switch from anti-glare to non-dimming.

Moreover, since only one type of voltage was supplied to the EC during anti-glare, the rise response speed during anti-glare was particularly slow, and a method of applying a high voltage in advance could be considered.
According to this, the lifespan of EC will be significantly shortened, so
It's not a special plan.

The present invention was created by focusing on these conventional problems, and it takes full advantage of the features of EC and minimizes the rise time when switching from anti-glare to non-anti-glare. The object of the present invention is to provide an EC drive circuit that can provide an anti-glare mirror that is both durable and has a long life.

[Means for solving problems]

The above-mentioned problems include a timer circuit that operates for a predetermined time at the same time the anti-glare signal is transmitted, a switching circuit that operates according to the timer circuit, and a switch circuit that supplies current to the EC while the timer circuit is operating. 2 positive DC constant voltage circuit, a switching circuit that operates while the anti-glare signal is being transmitted, and a first positive DC constant voltage circuit that is supplied to the EC while the anti-glare signal is being transmitted after the timer operation ends. This problem can be solved by configuring it with a voltage circuit.

[Effect]

At the same time that the anti-glare signal is output, the timer circuit operates to supply a high voltage to the EC for a predetermined time via the second constant voltage circuit, and after the predetermined time has elapsed, the anti-glare signal continues. While I'm there, I'm number one.
A low voltage is supplied to the EC via the constant voltage circuit in place of the high voltage mentioned above to speed up the rising reaction speed of the EC mirror during anti-glare, and to switch to a lower voltage after a certain period of time. In this way, we are trying to extend the lifespan of EC.

〔Example〕

The present invention will be described in detail below with reference to FIGS. 1 and 2. FIG. 1 shows a specific circuit configuration, and the same reference numerals as in FIG. 3 have the same functions. In Figure 1, 1 is a power switch, 2 is a switching circuit for switching between a dimming state and a non-dazzling state, 3 is a timer circuit, 4 is a switching circuit that operates only when the timer circuit is operating, and 5 is a switching circuit for switching between a dimming state and a non-dazzling state. A second constant voltage circuit 6 supplies current to the EC 7 while the timer circuit 3 is in operation, and a first constant voltage circuit 6 supplies current to the EC 7 while the anti-glare signal is being output after the timer circuit 3 ends. Further, a, b ₁ and b ₂ are the contacts of the switching circuits 2 and 4, respectively, GCS is the anti-glare control signal output circuit, Tr ₁ is a transistor that is turned on by its output signal, and Tr ₂ is the output signal of the timer circuit 3. It is a transistor that is turned on by

In FIG. 1, the operation will be explained as follows. First, the first constant voltage circuit 6 is activated by turning on the switch _SW1 . However, when the anti-glare control signal output circuit GCS is a non-dimming signal, switching circuits 2 and 4 do not operate, so each contact maintains the state shown in Figure 1, so the first constant voltage The output of circuit 6 is not output to EC7. In other words, this state is the non-dazzle state,
Indicates a state where the reflectance of the EC mirror is high (bright).

Next, when switch 1 is on and the anti-glare control signal output circuit GCS outputs an anti-glare signal, transistor Tr ₁ is turned on and relay A/1 is activated.
The contact a switches. At the same time, timer circuit 3 is activated, transistor Tr ₂ is turned on, and relay B/2 is activated.
is activated. As a result, the contacts b ₁ and b ₂ are switched, and the second constant voltage circuit 5 is activated. As a result,
The output of the constant voltage circuit 5 is connected to EC via contacts b ₂ and a.
7, the potential of the O terminal becomes higher than the potential of the R terminal, EC7 is colored, and the reflectance of the EC mirror decreases, resulting in a dark state.

Next, when the timer circuit 3 completes the timer measurement, the transistor Tr ₂ is turned off, and the relay B/2 is also deenergized, so that the contacts b ₁ and b ₂ are returned to their original state, and the connections shown in FIG. 1 are established. However, relay A/
1 is in operation while the anti-glare signal continues, so its contact a also remains switched. accordingly
The O terminal of EC7 is switched from the constant voltage circuit 5 to the output of the constant voltage circuit 6, and the output voltage of the constant voltage circuit 6 is applied until the anti-glare signal disappears, and the EC mirror maintains a low reflectance state (this condition indicates the mirror's anti-glare condition).

In this case, the voltage of the constant voltage circuit 5 shall be higher than the voltage of the constant voltage circuit 6, and the time of the timer shall be extremely short so as not to affect the life of the EC 7.

Next, the schematic structure of the EC mirror will be explained with reference to FIG. Figure 2 is a cross-sectional view of the EC mirror plate. In the figure, 8 is transparent glass, 9 is a transparent electrode (ITO), and 10 is a reduction colored film, such as WO ₃ or MoO _2. be. Reference numeral 11 denotes an electrolyte layer, for example, the liquid type is made of LiClO ₄ /propylene carbonate, and the solid type is made of Ta ₂ O ₅ , ZrO ₂ or the like. 12
is an oxidized colored film (PTPA), such as CrO ₂ , Ni
[CH] ₂ , Rh[OT] ₂ , etc. 13 is glass, 1
4 constitutes a mirror surface part (mirror) made of aluminum (Al, Cr).

Now, (+) is attached to the transparent electrode 9 on the oxidized colored film 12 side.
When a potential is applied and the transparent electrode 9 on the reduction colored film 10 side is set to a (-) potential, the oxidized colored film is oxidized and colored. On the other hand, the reduction colored film 10 is reduced and colored. That is, by setting the oxidation colored film 12 side to a (+) potential and the reduction colored film 10 side to a (-) potential,
EC mirrors have low reflectance.

Moreover, by setting the oxidation colored film 12 side to a (-) potential and the reduction colored film 10 side to a (+) potential,
The oxidized colored film 12 is reduced and becomes transparent, and the reduced colored film 10 becomes oxidized and transparent. That is, the oxidized colored film 12 is set to (-) potential, and the reduced colored film 10 is set to (+) potential.
By setting the potential, the EC mirror has a high reflectance. Furthermore, like a capacitor, the EC7 has the property of storing the supplied electric charge, so it is clear from the illustrated circuit operation that it can be utilized to the maximum extent.

[Effect of idea]

As is clear from the above-described embodiments, according to the present invention, the second constant voltage circuit supplies a high voltage to the EC for a predetermined period of time using a timer at the same time that the anti-glare signal is output, and the time elapsed time using the timer. Later, while the anti-dazzling signal continues, the first constant voltage circuit supplies a voltage lower than the voltage mentioned above to the EC, so the rising reaction speed of the EC mirror during anti-glare can be controlled. The advantage is that it can be done quickly. Furthermore, since the voltage is switched to a lower voltage after a predetermined period of time has elapsed, the life of the EC will not be adversely affected.

[Brief explanation of the drawing]

Figure 1 is an EC drive circuit for an anti-glare mirror to explain an embodiment of the present invention, Figure 2 is a cross-sectional structural diagram to explain the configuration of an EC mirror, and Figure 3 is a diagram of a conventional anti-glare mirror. It is an EC drive circuit diagram. 1... Switch, 2, 4... Switching circuit, 3... Timer circuit, 5... Second constant voltage circuit, 6... First constant voltage circuit, 7... Electrochromism (EC), 8
...Transparent glass, 9...Transparent electrode, 10...Reduction colored film, 11...Electrolyte layer, 12...Oxidation colored film, 13...
Glass, 14...Al(Cr).

Claims (1)

[Scope of utility model registration request] The anti-glare mirror drive circuit uses a mirror that uses electrochromism and a power switch that changes the reflectance of the mirror to prevent glare depending on the brightness of the headlights emitted by the following vehicle. a timer circuit that outputs an activation signal for a predetermined time at the same time that the anti-glare signal is output; a switching circuit that is activated by the timer circuit; and a second circuit that supplies current to the electrochromism while the timer circuit is activated. a DC constant voltage circuit; a switching circuit that operates while the anti-glare signal is being transmitted; and a first circuit that supplies current to the electrochromism while the anti-glare signal is being transmitted after the timer circuit has finished timing. An electrochromic anti-glare mirror comprising a constant voltage circuit and configured to apply a high voltage to the electrochromic for a predetermined period of time during anti-glare, and thereafter apply a low voltage.
Chromism drive circuit.