JPH0542638Y2 - - Google Patents

Description

[Detailed description of the invention] [Summary] In a transparent electrode switch panel having a front sheet provided with an edging portion that covers the outer periphery of a transparent electrode switch portion, a conductive layer is provided on the edging portion, and the edging portion is provided with a conductive layer. By connecting the transparent electrode switch section and ground through the discharge member, it is possible to prevent static electricity from entering the transparent electrode switch section.

[Industrial application field]

The present invention relates to a transparent electrode switch panel with anti-static measures.

For example, as audio equipment and other electrical components become more advanced, the number of switches increases, but in cars where space is limited, the space for operating the various switches and the space for displaying the functions of these switches are separate. It becomes difficult to secure. Therefore, in recent years, instead of switch operation buttons that occupy a large area, transparent front sheets have been developed that display these switch functions and can turn on and off the contacts, which are placed directly in front of the switch with transparent electrodes as contacts. There is a trend towards using electrode switch panels. The present invention refers to a structure in which static electricity countermeasures are applied to such a transparent electrode switch panel.

[Conventional technology]

FIGS. 6 and 7 are diagrams showing the structure of a conventional transparent electrode switch panel, with FIG. 6 being a partially sectional side view and FIG. 7 being a perspective view thereof.

Usually, the transparent electrode switch panel 10 includes a transparent electrode switch section 20 having lower and upper transparent electrodes 23 and 24, and a front sheet 30 that displays the functions of the transparent electrode switch section 20 and turns the electrodes on and off. Formed by combining. Further, the main parts of the transparent electrode switch section 20 include a base plate 21 made of acrylic resin or the like to ensure the strength of the entire switch panel, lower and upper electrode sheets 22 and 25 made of flexible polyester or the like, and oxidized It is composed of lower and upper transparent electrodes 23 and 24 made of a transparent conductor such as indium.

Here, the assembly procedure of the transparent electrode switch panel 10 will be explained. First, the lower electrode sheet 22 on which the lower transparent electrode 23 is formed is attached to the base plate 21 of an appropriate size by adhesive or the like. Further, an upper transparent electrode 24 that pairs with the lower transparent electrode 23 is formed on the electrode sheet 25 . This upper electrode sheet 25 is adhered to the lower electrode sheet 22 by a spacer 28, and the spacer 28 provides a certain clearance between the lower transparent electrode 23 and the upper transparent electrode 24. lastly,
Front sheet 30 with letters such as AM, FM printed on it
is attached to the upper electrode sheet 25 by adhesive or the like to complete the transparent electrode switch panel 10. In addition, in order to prevent the resistance of the transparent electrode switch from becoming unnecessarily high, a silver paste having a lower resistance than the transparent electrode is used on the outer periphery of the lower and upper transparent electrode sheets 22 and 25, as shown in FIG. Lower and upper wiring patterns 26, 2 printed with etc.
7 (However, in FIG. 8, the lower wiring pattern 26
(shown as a representative) are drawn out from the lower and upper transparent electrodes 23 and 24, respectively.
These wiring patterns 26 and 27 are further connected to circuit elements etc. via a flexible cable 70 (FIG. 7).

In FIG. 6, when the front sheet 30 is operated to turn on and off the lower and upper transparent electrodes 23 and 24, static electricity charged on the human body moves from the finger F through the surface of the front sheet 30 to the outer periphery. Between the insulating front plate 60 and the transparent electrode switch panel 10
Intrude into the interior from the space 32. After that, static electricity is removed from the lower and upper wiring patterns 26 and 27 on the outer periphery.
It enters the circuit and discharges into circuit elements through the flexible cable 70, causing malfunctions and electrostatic damage.

Conventionally, as a countermeasure for this, the upper electrode sheet 25
A front side pattern 29 printed with silver paste or the like is formed on the outer periphery of the front side (the side close to the front sheet 30), and a conductive wire (not shown) is connected from one end of the front side pattern 29.
etc. and connected it to ground. If this is done, it is expected that the static electricity that has entered from the gap 32 will reach the ground through the surface side pattern 29 closest to the front sheet 30 before entering the lower and upper wiring patterns 26 and 27.

[The problem that the idea aims to solve]

As mentioned above, it has been conventionally believed that the front side pattern 29 formed on the front side of the upper electrode sheet 25 is effective as a countermeasure against static electricity. However, upon actual confirmation, the following unexpected facts were revealed. In other words, even though the front side pattern 29 is closest to the source of static electricity,
The static electricity scattered in the air in step 2 enters the lower wiring pattern 26, the upper wiring pattern 27, and the front side pattern 29 with approximately the same probability. As a result, the following problems arise.

That is, even if the front side pattern 29 is provided, static electricity is not completely blocked, so there remains a possibility that malfunction of circuit elements or electrostatic damage may occur. Therefore, the withstand voltage of electrical components against static electricity is limited to a low value.

In addition, in this case, static electricity is caused by wiring pattern 2.
6, 27, the width of the front side pattern 29 is set to the width of the wiring pattern 2.
It is also possible to make the resistance lower by making the width wider than the width of 6 and 27. However, as the pattern width becomes wider, the display space on the front sheet 30 decreases, so it is not a good idea to apply it to electrical equipment inside a car where space is limited.

The present invention has been developed in view of the above-mentioned problems, and completely prevents static electricity from entering the transparent electrode switch section 20, thereby preventing malfunction of circuit elements and electrostatic damage, and reducing display space. The purpose of the present invention is to provide a transparent electrode switch panel that will never cause problems.

[Means to solve the problem]

FIG. 1 is a side view showing, in partial cross section, the principle structure of the present invention. Note that detailed description of the inside of the transparent electrode switch section 20 (FIG. 6) is omitted here.
Further, components similar to those described above are designated by the same reference numerals.

In order to solve the above problems, the present invention provides lower and upper transparent electrodes 23 and 2 made of transparent conductors.
4 (FIG. 6)
and lower and upper wiring patterns 2 drawn out from these transparent electrodes 23 and 24 and formed on the outer periphery of the transparent electrode switch section 20.
6, 27 (FIG. 6) and has an opaque border 40 that can cover and hide these wiring patterns 26, 27. 40 by printing,
Further, a conductive layer 41 having a lower resistance than the wiring patterns 26 and 27 and a discharge member 50 that electrically connects the conductive layer 41 and the ground are provided.

Preferably, the edging portion 40 is formed on the outer periphery of the back surface of the front sheet 30 in such a way as to completely cover the wiring patterns 26 and 27 so that the wiring patterns 26 and 27 do not spoil the aesthetic appearance. It is formed. In this case, the front sheet 30
This front sheet 3
0 is larger than the transparent electrode switch part 20, and the border part 40 is made larger than the wiring pattern 2.
6.27. Further, a conductive layer 41 is provided on this edge portion 40, and this conductive layer 41
One end is electrically connected to earth E by a discharge member 50.

Furthermore, preferably, the edging portion 40 is constituted by an edging pattern 42 made of a conductive material, and this edging pattern 42 itself forms the conductive layer 41.

[Effect]

In FIG. 1, the conductive layer 41 is
Since the front sheet 30 is placed close to the surface of the front sheet 32 and protrudes from the outer periphery of the transparent electrode switch section 20, static electricity from the surface of the front sheet 30 is conductive before scattering into the air in the front sheet 32 (FIG. 6). It is absorbed into layer 41. Furthermore, since the conductive layer 41 has a wider pattern width than the lower and upper wiring patterns 26, 27 (FIG. 6), it has a lower resistance than these wiring patterns 26, 27, and thus absorbs static electricity more easily. Become.

The static electricity absorbed by the conductive layer 41 in this way passes through the discharge member 50 and is all discharged to the earth E, making it possible to prevent static electricity from entering the transparent electrode switch section 20. Moreover, since the conductive layer 41 is formed on the border 40 that is normally formed on the transparent electrode switch panel 10, the display space will not be reduced.

Furthermore, since this conductive layer 41 is formed by printing to overlap the edge portion 40, the edge portion 41 serves as a base substrate for forming this type of conductive layer.
For this purpose, a thin sheet-like member made of a non-conductive material may be prepared. Since such members can be inexpensive, the occupied area can be reduced and costs can be reduced.

Furthermore, the above-described conductive layer 41
Taking advantage of the fact that it is formed overlappingly by printing,
By adjusting the resistance value of the edging portion 40 consisting of the edging pattern 42 and the like to be lower than that of the wiring patterns 26 and 27, the edging portion 40 and the conductive layer 41 can be used in common. Man-hours are saved.

〔Example〕

FIGS. 2 and 3 are views showing an embodiment of the present invention, with FIG. 2 being a partially sectional side view and FIG. 3 being an assembled perspective view thereof.

Here, the front sheet 30 is used as the edging portion 40.
The conductive layer 41 is provided by printing a grounding pattern 45 such as silver paste on top of an insulator edging pattern 42 printed in advance on the back side of the substrate. In this case, since the grounding pattern 45 comes into contact with the conventional front side pattern 29, its resistance is further reduced and the static electricity from the finger F is reliably absorbed by the grounding pattern 45. At one end of the part of the grounding pattern 45 that protrudes from the outer periphery of the transparent electrode switch part 20, a metal foil such as a band-shaped aluminum foil, which has a lower resistance than a conductive wire and does not take up much space, is attached as a discharge member 50. 52 are connected. Furthermore, this metal foil 52 passes through a hole 51 provided in the front plate 60 and passes through the conductor chassis 5.
5, and this chassis 55 is finally connected to earth E. Therefore, the static electricity absorbed by the grounding pattern 45 passes through the metal foil 52 and reaches the chassis 55 connected to the ground E, so it does not have any effect on the transparent electrode switch section 20 or the circuit elements. Furthermore, since the grounding pattern 45 is not visible from the front (FIG. 3), it does not cause any visual inconvenience.

In this embodiment, a grounding pattern 45 made of silver paste as a conductive layer 41 is overprinted on the existing edging pattern 42. It is also possible to use only the edging pattern 42 which has been adjusted to have low resistance from the beginning by appropriately mixing conductive carbon or the like. In this case, since the edging pattern 42 itself forms the conductive layer 41, the number of man-hours is saved.

FIG. 4 is a partial cross-sectional side view of a first application example of the present invention, and FIG. 5 is a partial cross-sectional side view showing a second application example of the present invention.

In FIG. 4, the present invention is applied to a transparent electrode switch portion in which the surface side pattern 29 is not formed on the surface side of the upper electrode sheet 25, and in FIG. 5, the lower and upper electrode sheets 22 made of polyester etc. , 25, the present invention is applied to a transparent electrode switch section in which lower and upper electrode plates 35 and 36 made of thin glass or the like are provided instead of the lower and upper electrode plates 35 and 36 made of thin glass or the like. Even if there is no surface side pattern 29 as shown in FIG. 4, the thickness of the grounding pattern 45 can be increased to form a grounding pattern 45 having the same resistance as the embodiment of the present invention (FIG. 2). Transparent electrode switch panel 10
With this configuration, static electricity is reliably absorbed by the grounding pattern 45, making it possible to apply the present invention. In addition, as shown in FIG. 5, there is no base plate 21, and instead, electrode plates 35 and 36 for forming transparent electrodes 23 and 24 have a certain strength. However, the fourth
The present invention can be applied by using a grounding pattern 45 similar to that shown in the figure.

[Effect of idea]

As explained above, according to the present invention, a transparent electrode switch panel is realized that completely prevents static electricity from entering the switch section from the front sheet, thereby preventing malfunction of circuit elements and electrostatic damage. It becomes possible to do so. Furthermore, as a result of a voltage resistance test against static electricity, the voltage resistance increased by more than 1.5 times, confirming an improvement in safety.

Furthermore, since the border is used as a countermeasure against static electricity, the display space will not be reduced and the appearance will not be spoiled.

Furthermore, since the conductive layer for guiding static electricity to the ground is formed by printing on the border, an inexpensive non-conductive sheet-like member may be prepared as the border. The occupied area can be saved and costs can be reduced. Furthermore, by adjusting the resistance value of the edging part to a relatively low resistance so that the edging part and the conductive layer can be used in common, the number of man-hours can be saved.

[Brief explanation of the drawing]

Fig. 1 is a side view showing the principle structure of the present invention in partial cross section, Fig. 2 is a side view showing an embodiment of the present invention in partial cross section, and Fig. 3 is an assembled perspective view of one embodiment of the present invention. FIG. 4 is a side view showing a first application example of the present invention in partial cross section; FIG. 5 is a side view showing a second application example of the present invention in partial cross section; FIG. 7 is a side view showing the structure of a conventional transparent electrode switch panel in partial cross section, FIG. 7 is a perspective view showing the structure of a conventional transparent electrode switch panel, and FIG. 8 is a part showing the structure of transparent electrodes and wiring patterns. FIG. DESCRIPTION OF SYMBOLS 10... Transparent electrode switch panel, 20... Transparent electrode switch part, 21... Base plate, 22...
Lower electrode sheet, 23... Lower transparent electrode, 24...
... Upper transparent electrode, 25 ... Upper electrode sheet, 26
... lower wiring pattern, 27 ... upper wiring pattern, 30 ... front sheet, 40 ... edging section, 41 ... conductive layer, 45 ... grounding pattern, 50 ... discharge member, 55 ... chassis .

Claims (1)

[Claims for Utility Model Registration] 1. Transparent electrode switch section 20 having lower and upper transparent electrodes 23 and 24 made of a transparent conductor.
The lower and upper wiring patterns are drawn out from the lower and upper transparent electrodes 23 and 24 and are larger than the lower and upper wiring patterns 26 and 27 formed on the outer periphery of the transparent electrode switch section 20. 26, 27, and a front sheet 30 having an opaque border 40 capable of covering and concealing 26 and 27, the front sheet 30 is formed by printing to overlap the border 40, and the lower and upper wiring A transparent electrode switch panel characterized by being provided with a conductive layer 41 having a lower resistance than the patterns 26 and 27, and a discharge member 50 electrically connecting the conductive layer 41 and ground. 2. The transparent electrode switch panel according to claim 1, wherein the edging portion 40 is composed of an edging pattern 42 made of a conductive material, and the edging pattern 42 itself forms the conductive layer 41.