JP5659951B2 - Input device - Google Patents

Description

  The present invention relates to static electricity countermeasures in an input device including a touch panel.

  In recent years, many printers, copiers, mobile phones, and the like have adopted touch panels that allow users to perform input operations by directly touching the surface. FIG. 4 is a perspective view of a conventional input device. FIG. 5 is a cross-sectional view showing a YY cross section of a conventional input device.

  Static electricity is likely to be generated on the surface of the touch panel 110, and the generated static electricity is discharged from the surface of the touch panel 110 to the inside of the input device 100 through the side surface and the surface of the housing 130. Inside the input device 100 is a substrate 120 on which an LED 122 serving as a light source of the touch panel 110, a touch sensor, a circuit for controlling the input device 100, and the like are arranged. Therefore, when static electricity reaches the substrate 120, a malfunction or failure of the input device 100 occurs.

  For this reason, in the conventional input device 100, an antistatic member such as an aluminum tape 150 is disposed in the middle of a discharge path from the surface of the touch panel 110 to the substrate 120 to absorb static electricity discharged from the surface of the touch panel 110 and input. The substrate 120 inside the apparatus 100 was prevented from reaching.

Japanese Patent Laid-Open No. 04-186277 Japanese Utility Model Laid-Open No. 05-0607020 Japanese Patent Application Laid-Open No. 11-149843

  However, when a static electricity countermeasure member such as the aluminum tape 150 is provided to take a static electricity countermeasure, it is necessary to secure a place where the static electricity countermeasure member is provided or a ground where the static electricity absorbed by the static electricity countermeasure member is provided. Therefore, the conventional input device 100 has a problem that its shape, size, design, and the like are restricted.

  On the other hand, in Patent Documents 1 to 3, countermeasures against static electricity are taken without providing an electrostatic countermeasure member. For example, in Cited Document 1, a connecting portion is provided to increase the creepage distance. Further, in Cited Document 2, a recess is provided on the surface of the light emitting element or the cover that covers the light emitting element, and a protruding piece that fits into the recess is provided on the housing. In Cited Document 3, two or more ribs are provided on the key rubber, and ribs that fit into the spaces between the ribs are provided on the case. However, none of the cited references 1 to 3 is a countermeasure against static electricity on the touch panel.

  In view of the above-described problems, an object of the present invention is to provide an input device capable of taking measures against static electricity on a touch panel without using an anti-static member.

  In order to achieve the above object, an input device of the present invention includes a touch panel, a substrate disposed behind the touch panel, and a housing, and the touch panel includes a plate-like insulating member, and the housing Has an extension part provided between the touch panel and the substrate, and a rib extending from the extension part, and the rib passes from the housing to the back of the substrate through an opening provided in the substrate. Extend to.

  According to the above configuration, since the rib extends from the extended portion of the housing to the back of the substrate through the opening provided in the substrate, the discharge path from the surface of the touch panel to the substrate is made sufficiently long, and electrostatic discharge Can be prevented from reaching the substrate from the surface of the touch panel. Accordingly, the substrate inside the input device can be protected from static electricity on the surface of the touch panel. Therefore, it is possible to take countermeasures against static electricity on the touch panel without using a countermeasure against static electricity.

In the above configuration, the substrate holding member that holds the substrate is further provided, the plate-like insulating member is translucent, and the substrate has a light emitting element on a surface opposite to a surface facing the touch panel. The light emitted from the light emitting element may be reflected by the inner surface of the substrate holding member and may enter the touch panel through the opening provided in the substrate.

  In the above configuration, the rib may have a cylindrical shape, and the height of the rib is higher on the shorter side than on the longer creepage distance from the surface of the touch panel to the substrate. It may be a thing.

  According to the present invention, since the rib extends from the extended portion of the housing to the back of the substrate through the opening provided in the substrate, the discharge path from the surface of the touch panel to the substrate is made sufficiently long, and electrostatic discharge Can be prevented from reaching the substrate from the surface of the touch panel. Accordingly, the substrate inside the input device can be protected from static electricity on the surface of the touch panel. Therefore, it is possible to take countermeasures against static electricity on the touch panel without using a countermeasure against static electricity.

It is a perspective view of the input device concerning a 1st embodiment. It is sectional drawing which shows the XX cross section of the input device which concerns on 1st Embodiment. It is sectional drawing of the input device which concerns on 2nd Embodiment. It is a perspective view of the conventional input device. It is a figure which shows the YY cross section of the conventional input device.

Embodiments of the present invention will be described below with reference to the drawings.
<First Embodiment>

  FIG. 1 is a perspective view of the input device according to the first embodiment. FIG. 2 is a sectional view showing an XX section of the input device according to the first embodiment. The input device 1a includes a touch panel 10, a substrate 20, a housing 30, and a substrate holder 40 (substrate holding member). In the input device 1a, the user can input an operation by touching the surface of the touch panel 10.

  The touch panel 10 is a capacitive touch panel, and includes an acrylic plate 11 (a plate-like insulating member), a sensor layer 12, and a light diffusion sheet 13. Note that the present invention is not limited to this, and for example, a touch panel such as a resistive film type can be used.

  The acrylic plate 11 is a plate-like insulating member having translucency. In addition, if it is a plate-shaped insulating member having translucency, it can be used in place of the acrylic plate 11. For example, plate glass may be used.

  Various characters and figures are printed on the back surface of the acrylic plate 11. For example, the user can recognize that the user can perform an input operation by touching a predetermined surface area of the touch panel 10 by printed characters and graphics. Note that these characters and figures may be printed on the surface of the acrylic plate 11. Furthermore, it may replace with printing of a character and a figure, and may affix the printing sheet on which the character and the figure were printed previously on the surface or back surface of the acrylic board 11. FIG.

  The sensor layer 12 is formed between the acrylic plate 11 and the light diffusion sheet 13. In addition, the sensor layer 12 includes a touch sensor circuit unit 12a that detects whether or not an input operation is performed on a predetermined surface region of the touch panel 10 (for example, a surface region located immediately above an opening 21 described later). As this touch sensor circuit part 12a, the electrode part comprised by a sensor wire can be mentioned, for example. The touch sensor circuit unit 12a is connected to a controller (not shown). When the user touches a predetermined surface area of the touch panel 10, a capacitance change occurs and the frequency of the pulse signal input to the sensor wire changes. The controller detects the coordinate position touched by the user based on this frequency change.

  The light diffusion sheet 13 is provided on the back surface side of the touch panel 10, diffuses light incident from behind the touch panel 10, and is a predetermined surface region of the touch panel 10 (for example, a surface located directly above the touch sensor circuit unit 12a). Area). The light diffusion sheet 13 suppresses the occurrence of bright spots, dots, bright lines, light unevenness and the like in the surface area of the touch panel 10.

  The substrate 20 is disposed close to the back of the touch panel 10 by the substrate fixing member 33. An opening 21 is provided in the substrate 20. Hereinafter, the surface facing the touch panel 10 is referred to as the surface of the substrate 20, and the surface opposite to the surface of the substrate 20 is referred to as the back surface of the substrate 20. On the back surface of the substrate 20, an LED 22 (light emitting element) for causing a predetermined surface region of the touch panel 10 to emit light is provided.

  The housing 30 includes an extension part 31 and a rib 32. The housing 30 is made of resin, and for example, polycarbonate or ABS resin is used as the material.

  The extension part 31 is a part of the housing 30 and is provided between the touch panel 10 and the substrate 20. The extending portion 31 is in contact with the back surface of the touch panel 10 and is provided close to the substrate 20. Further, the extending part 31 completely covers the surface of the substrate 20. In addition, it is not limited to this, The extension part 31 may be provided in the vicinity of the back surface of the touch panel 10, and may be in contact with the surface of the board | substrate 20. FIG.

  The rib 32 is a part of the housing 30 that extends from the extending portion 31 to the opening 21 of the substrate 20, and extends from the extending portion 31 of the housing 30 to the back of the substrate 20 through the opening 21. The rib 32 has a cylindrical shape. Further, the rib 32 may have a tapered shape. As will be described later, the rib 32 has a height set in advance based on a creeping distance from the surface of the touch panel 10 to the substrate 20.

  Further, a reflection film for improving the reflectance of light, such as an aluminum vapor deposition film, may be formed on the inner surface of the rib 32. By so doing, the reflected light incident on the inner surface of the rib 32 can be further reflected and more light can be incident on the back surface of the touch panel 10, so that the utilization efficiency of the light emitted from the LED 22 can be improved.

  The substrate holder 40 is a resin member that holds the substrate 20, and at least the inner surface thereof is white. Therefore, the inner surface of the substrate holder 40 can reflect the light emitted from the LED 22. A part of the reflected light enters the back side of the touch panel 10 through the inside of the rib 32. Note that a reflective film for improving the reflectance of light, such as an aluminum vapor deposition film, may be formed on the inner surface of the substrate holder 40.

  In such an input device 1a, static electricity may be generated on the surface of the touch panel 10 due to operation input by the user or the like. Since the touch panel 10 includes the insulating acrylic plate 11, electrostatic discharge does not occur directly from the surface of the touch panel 10 to the substrate 20. However, static electricity on the surface of the touch panel 10 is discharged through a discharge path formed along the surface of an insulating member such as the touch panel 10 or the housing 30. Generally, such a discharge phenomenon is called creeping discharge. In addition, among the discharge paths formed by creeping discharge, the length of the discharge path that has the shortest linear distance from the surface of the touch panel 10 to the substrate 20 is called the creeping distance. If this creepage distance is sufficiently long, even if static electricity on the surface of the touch panel 10 is creepingly discharged, it will not reach the substrate 20. Therefore, the substrate 20 inside the input device 1 a can be protected from static electricity generated on the surface of the touch panel 10.

  In the present embodiment, by extending the rib 32 from the extended portion 31 of the housing 30 to the back of the substrate 20 through the opening 21, the creepage distance from the surface of the touch panel 10 to the substrate 20 is increased, and the surface of the touch panel 10 is increased. And a length necessary to electrically insulate the substrate 20 from each other. For example, in the conventional input device 100 as shown in FIG. 5, when static electricity generated on the surface of the touch panel 110 is creeping, the substrate 120 passes from the surface of the touch panel 110 to the side surface, between the touch panel 110 and the housing 130. Will be reached.

  On the other hand, in the present embodiment, the discharge path when static electricity is creeping discharged is as indicated by an arrow A in FIG. That is, when static electricity generated on the surface of the touch panel 10 is creepingly discharged, the surface from the surface of the touch panel 10 to the side surface, between the touch panel 10 and the housing 30 (for example, the surface on the side toward the extending portion 31 of the light diffusion sheet 13, The surface of the housing 30 and the extension part 31 on the side facing the light diffusion sheet 13) and the inner surface of the rib 32 reach the substrate 20 via the tip surface and the outer surface.

  Thus, in the present embodiment, the creepage distance can be increased by an amount from the inner surface of the rib 32 via the tip surface and the outer surface, compared to the discharge path in the conventional input device 100. Moreover, the height of the rib 32 is set so that the creepage distance between the surface of the touch panel 10 and the substrate 20 can secure a length necessary for electrically insulating the two. Therefore, even if static electricity on the surface of the touch panel 10 is creepingly discharged, it cannot reach the substrate 20 inside the input device 1a. Accordingly, the substrate 20 inside the input device 1a can be protected from static electricity on the surface of the touch panel 10. Therefore, it is possible to take countermeasures against static electricity on the touch panel 10 without using an anti-static member such as an aluminum tape as in the prior art.

  If the rib 32 is higher than necessary, for example, the light of the LED 22 reflected by the inner surface of the substrate holder 40 is likely to be blocked by the rib 32, so that the light irradiated on the back surface of the touch panel 10 is reduced. There arises a problem that the utilization efficiency of the emitted light is lowered. However, if the height of the rib 32 can be appropriately determined based on the creepage distance necessary for protecting the substrate 20 from electrostatic creeping discharge as in the present embodiment, the reflected light blocked by the rib 32 can be reduced. Since the number can be reduced, the utilization efficiency of the light emitted from the LED 22 can be improved.

In the present embodiment, the extending portion 31 completely covers the surface of the substrate 20, but as a modification thereof, the creeping distance from the surface of the touch panel 10 to the substrate 20 is reduced from electrostatic creeping discharge. The extension 31 may cover a part of the surface of the substrate 20 as long as a sufficient length for protection can be secured.
Second Embodiment

  Further, the height of the ribs 32 may not be uniform as long as the creepage distance from the surface of the touch panel 10 to the substrate 20 can secure a length that can sufficiently protect the substrate 20 from electrostatic creeping discharge. FIG. 3 is a cross-sectional view of the input device according to the second embodiment. In addition, about the member which is common in 1st Embodiment, the same code | symbol is attached | subjected and the description is abbreviate | omitted.

  In the input device 1b, the rib 32b on the short side is higher than the rib 32a on the side where the creepage distance from the surface of the touch panel 10 to the substrate 20 is long. The heights of the ribs 32a and 32b are set so that the creepage distance from the surface of the touch panel 10 to the substrate 20 can secure a length that can sufficiently protect the substrate 20 from electrostatic creeping discharge. In addition, on the back surface of the substrate 20, the LEDs 22 are arranged close to the ribs 32 a on the longer creepage distance side. Other than that, the configuration is the same as that of the first embodiment.

  In this way, the reflected light blocked by the rib 32 can be reduced. Accordingly, it is possible to protect the substrate 20 from static electricity on the surface of the touch panel 10 and to allow more reflected light to enter the touch panel 10 at the same time. Therefore, the utilization efficiency of the light emitted from the LED 22 can be further improved.

  In the above, this invention was demonstrated based on embodiment. These embodiments are exemplifications, and various modifications may be made to each component and combination of processes, and it is understood by those skilled in the art that they are within the scope of the present invention.

1a, 1b, 100 Input device 10, 110 Touch panel 11 Acrylic plate (plate-like insulating member)
DESCRIPTION OF SYMBOLS 12 Sensor layer 12a Touch sensor part 13 Light-diffusion sheet 20, 120 Board | substrate 21, 121 Opening 22, 122 LED (light emitting element)
30, 130 Housing 31 Extension part 32 Rib 33 Substrate fixing member 40, 140 Substrate holder (substrate holding member)
150 Aluminum tape (electrostatic countermeasure material)

Claims (6)

A touch panel, a substrate disposed on one side of the touch panel, and a housing,
The touch panel has a plate-like insulating member,
The housing includes an extending portion provided between the touch panel and the substrate, and a rib extending from the extending portion,
The input device according to claim 1 , wherein the rib extends from the housing to a surface opposite to a surface of the substrate facing the housing through an opening provided in the substrate. A substrate holding member for holding the substrate;
The plate-like insulating member is translucent,
The substrate is provided with a light emitting element on the surface opposite to the surface facing the touch panel,
2. The input according to claim 1, wherein light emitted from the light emitting element is reflected by an inner surface of the substrate holding member and is incident on the touch panel through the opening provided in the substrate. apparatus. The input device according to claim 1, wherein the rib protrudes from a surface opposite to a surface of the substrate facing the housing. The input device according to claim 1, wherein the height of the rib is preset based on a creeping distance from the surface of the touch panel to the substrate. The input device according to claim 1, wherein the rib has a cylindrical shape. 6. The input according to claim 1, wherein the height of the rib is higher on a side shorter than a side having a long creepage distance from the surface of the touch panel to the substrate. apparatus.

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