JP2009032588A - Switch device - Google Patents

Abstract

An object of the present invention is to improve the click characteristics and reduce the thickness.
A switch device 1 is arranged for covering a contact portion 5A on a substrate 3 so as to be substantially centered, and for a switch made of a flexible bowl-shaped conductive material that can be contacted and separated from the contact portion 5A. A dome 7, a light-reflective dome presser sheet 9 that places and holds the switch dome 7 at a predetermined position on the substrate 3, and an upper sheet 17 having a dot portion 15 that faces the apex of the switch dome 7. A spacer 11 having a hole 11A disposed around the switch dome 7 below the upper sheet 17, and the upper sheet 17 and the dome presser sheet 9, and the dome presser And a light emitter 13 that irradiates the sheet 9.
[Selection] Figure 1

Description

  The present invention relates to a switch device, and in particular, a switch device including a light emitting body having a light emitting function such as an LED or an EL, and is a thin switch excellent in click characteristics for operation incorporated in a small electronic device such as a mobile phone. Relates to the device.

  In general, a key switch 101 for operation used in a mobile electronic device typified by a mobile phone is basically the same as that shown in, for example, Patent Document 1, and as shown in FIG. In addition, it is incorporated in the housing 103 of the electronic device. In addition to the above mobile phone, the electronic device includes, for example, a digital camera, a PDA, an MD (trade name), a CD (trade name) player, or other electronic devices.

  Further, inside the housing 103, one contact portion 107A made of a conductive material is provided on a printed wiring board 105 such as a PCB (Printed Circuit Board) or an FPC (Flexible Printed Circuit). The other contact portion 107B is annularly provided around the portion 107A.

  A switch dome 109 (metal dome) made of a bowl-shaped conductive material is disposed on each of the contact portions 107A and 107B. That is, the switch dome 109 is flexible so as to be able to contact and separate from the one contact portion 107A, and is placed with its outer periphery connected to the other contact portion 107B. The switch dome 109 is formed by processing, for example, a stainless steel or copper-based metal plate as a conductive material. Further, the switch dome 109 is disposed so as to cover one contact portion 107A substantially at the center, that is, the other contact portion 107A is located on the center direction side of the bowl-shaped concave surface. The dome 109 for switch is positioned by being pressed on the substrate 105 by sticking the convex surface side of the bowl shape with a dome presser sheet 111 made of, for example, a resin sheet.

  The dome presser sheet 111 is made of, for example, PET (polyethylene terephthalate) as a base material and reflects light, a sheet material 111A (light diffusion sheet), and, for example, an acrylic or silicon-based adhesive coated on one surface of the sheet material 111A. The pressure-sensitive adhesive layer 111B that holds the switch dome 109 is the same as the pressure-sensitive adhesive attached to the surface of the substrate 105 as it is.

  Further, in the key switch 101, for example, a key mat 113 as an actuator for pushing the switch dome 109 is disposed above the dome presser sheet 111 at a position separated from the printed wiring board 105.

  The key mat 113 is obtained by attaching a hard plastic such as polycarbonate to a silicon rubber or urethane sheet. The key mat 113 has a protruding dot portion 115 for pushing the switch dome 109.

  The key mat 113 is provided inside the housing 103, and is assembled using a positioning hole or the like so that the dot portion 115 of the key mat 113 is directly or indirectly positioned directly above the switch dome 109. It is done.

  A light emitter 117 such as an LED is mounted on the substrate 105. The light from the light emitter 117 is reflected by the dome presser sheet 111, so that the light emitter 117 serves as a backlight.

Therefore, when the key mat 113 is pushed by a human finger, the vicinity of the apex of the switch dome 109 is pushed down from above the dome presser sheet 111. The switch dome 109 is pushed in so that the vicinity of the top of the dome 109 is inverted and recessed, and comes into contact with one of the contact portions 107 </ b> A and becomes conductive, and the key switch 101 is turned on to emit light from the light emitter 117. Light is reflected by the dome presser sheet 111. Further, as described above, when the switch dome 109 is inverted and recessed, a click feeling can be obtained. The key switch 101 is required to have good operation feeling and high conductivity.
JP 2006-127799 A

  By the way, in recent years, electronic devices have been reduced in size and thickness. However, when the structure of the conventional key switch 101 is used, the total thickness of the electronic device becomes thick, and the electronic device cannot be housed in the thinned housing 103. There was a problem.

  For example, the above-described key mat 113 or the like has a thickness of 1 mm or more, which makes it difficult to reduce the thickness. Further, in the case of Patent Document 1, since the switch portion has a thick structure, it is disadvantageous for thinning. For example, it is practically difficult to manufacture the key switch 101 having a total thickness of 1 mm or less.

  In the conventional configuration, the key mat 113 and the substrate 105, the switch dome 109, the dome presser sheet 111, and the like, which are components, need to be individually incorporated in the housing 103, which increases the manufacturing cost. It was.

  An object of the present invention is to provide a switch device that has excellent click characteristics and can be thinned.

In order to solve the above-mentioned problems, a switch device according to the present invention is arranged so as to cover a contact portion on a substrate substantially at the center, and is a flexible bowl-shaped conductive material that can be contacted and separated from the contact portion. A switch dome consisting of
A light-reflective dome presser sheet that places and holds the switch dome at a predetermined position on the substrate;
An upper sheet having a dot portion facing the apex of the switch dome;
A spacer having a hole disposed around the switch dome below the upper sheet;
A light emitter that is disposed between the upper sheet and the dome presser sheet and irradiates the switch dome;
It is characterized by comprising.

  In the switch device according to the present invention, the total thickness from the substrate to the upper sheet is preferably 1 mm or less in the switch device.

  Further, according to the switch device of the present invention, in the switch device, the thickness of the switch portion from the substrate passing through the apex portion of the switch dome to the surface of the upper sheet, and from the substrate positioned at the spacer to the surface of the upper sheet The difference from the thickness of the spacer portion is preferably 0 mm or more and 0.5 mm or less.

  In the switch device according to the present invention, it is preferable that an inner diameter of the hole of the spacer is 0.5 mm or more larger than a diameter of the switch dome.

  In the switch device according to the present invention, in the switch device, it is preferable that the light emitter is disposed at a position of 0.5 mm or more and less than 5 mm from an outer peripheral edge of the switch dome.

  As can be understood from the means for solving the above-described problems, according to the present invention, the switch device equipped with a light emitter such as an LED has an upper sheet having a dot portion facing the apex of the switch dome. In addition, by using a structure using a spacer having a hole disposed around the switch dome below the upper sheet, it can be easily housed in a thin electronic device. Moreover, although the total thickness is less than 1 mm, it is possible to irradiate and reflect the light of the illuminant to the dome presser sheet on the dome for the switch, although it is thin. It can be set as the outstanding switch apparatus.

  Embodiments of the present invention will be described below with reference to the drawings.

  1 and 2, the switch device 1 according to this embodiment is used in a mobile phone, a digital camera, a PDA, an MD (trade name), a CD (trade name) player, or other electronic devices. Is.

  Further, the switch device 1 includes one contact portion 5A made of a conductive material on a printed wiring board 3 such as a PCB (Printed Circuit Board) or an FPC (Flexible Printed Circuit), and the one contact portion 5A. The other contact portion 5B is annularly provided around the.

  Each of the contact portions 5A and 5B is provided with a switch dome 7 made of a conductive material that turns ON / OFF the conduction between the one contact portion 5A and the other contact portion 5B. For example, a metal dome as the switch dome 7 has a flexible saddle shape that can be brought into contact with and separated from the one contact portion 5A, and the outer periphery thereof is connected to the other contact portion 5B. Is. The switch dome 7 has a diameter A of, for example, 3.0 to 5.0 mm and a height B of, for example, 0.2 to 0.3 mm. The switch dome 7 is formed by processing a plate material made of, for example, stainless steel or copper metal as a conductive material. Further, the one contact portion 5A is covered so as to be substantially in the center, that is, the one contact portion 5A is located on the center direction side of the bowl-shaped concave surface. Accordingly, when the apex of the switch dome 7 is pressed downward, the vicinity of the apex is reversed so as to be depressed so as to come into contact with the one contact portion 5A and to be conducted. The switch dome 7 is positioned on the substrate 3 by a dome presser sheet 9 made of, for example, a resin sheet on the convex surface side of the bowl shape.

  The dome presser sheet 9 is made of, for example, PET (polyethylene terephthalate) as a base material and reflects light, and a sheet material 9A (light diffusion sheet), for example, an acrylic or silicon-based adhesive applied to one surface of the sheet material 9A. The pressure-sensitive adhesive layer 9 </ b> B that holds the switch dome 7 is the same as the pressure-sensitive adhesive attached to the surface of the substrate 3 as it is.

  Referring also to FIG. 2, a spacer 11 having a hole 11 </ b> A surrounding the switch dome 7 is disposed on the dome presser sheet 9. The outer shape of the spacer 11 may be a donut shape having a substantially circular shape, the plate-shaped spacer 11 may be provided with the hole 11A at a position where the switch dome 7 is disposed, or other It may be an outer shape.

  Further, a light emitter 13 such as an LED is mounted on the substrate 3. In this embodiment, a notch provided so that the irradiation light of the light emitter 13 faces the inner diameter side of the hole 11 </ b> A of the spacer 11. It is provided in the part 11B. Moreover, it is provided sideways so as to emit light toward the light reflecting dome presser sheet 9 on the switch dome 7. Therefore, the light emitted from the light emitter 13 is reflected by the dome presser sheet 9, so that the light emitter 13 serves as a backlight. The light emitter 13 is not limited to the above-described LED, and may be, for example, EL (electroluminescence) or another form of light emitter 13.

  In addition, above the dome presser sheet 9, a dot portion 15 for pressing the apex of the switch dome 7 downward is disposed at a predetermined position, and the upper sheet 17 includes the light emitter 13 and the spacer. 11 is interposed. The dot portion 15 acts as an actuator for pushing the apex portion of the switch dome 7 in order to turn on / off the conduction between the contact portion 5A and the contact portion 5B.

  With the above configuration, when the upper sheet 17 on the switch dome 7 is pushed in by a human finger, the dot portion 15 pushes down the vicinity of the apex of the switch dome 7 from above the dome presser sheet 9. The switch dome 7 is pushed in so that its apex portion is inverted and recessed, and is brought into contact with the contact portion 5A, so that the switch device 1 is turned on. When this switch is turned on, the light emitted from the light emitter 13 is reflected by the dome presser sheet 9. Further, as described above, when the switch dome 7 is inverted and recessed, a click feeling can be obtained.

  Next, Examples 1 to 9 based on the configuration of the switch device 1 of the above-described embodiment are created, and in order to compare with the switch device 1 of this embodiment, Comparative Examples 1 to 5 It was created. In addition, the same code | symbol is attached | subjected to the same member in each Example and each comparative example, detailed description is abbreviate | omitted, and a different point is mainly demonstrated in detail.

[Example 1]
As a constituent material of the switch device 1 of the first embodiment, the substrate 3 is a known printed wiring board, and the material of the substrate 3 is polyimide. The diameter A (referred to herein as “metal dome diameter”) of the switch dome 7 is 4.0 mm, and the height B is 0.23 mm.

  The material of the spacer 11 is “No. 507” manufactured by Nitto Denko Corporation. The thickness C of the spacer 11 is 0.3 mm, and the inner diameter D of the hole 11B of the spacer 11 (here, “spacer 11”). (Referred to as “diameter”) is 8 mm. Further, the light emitter 13 uses a side-emitting LED, and is a system in which light is emitted by being reflected upward at the switch dome 7 portion.

  In Example 1, “spacer diameter” − “metal dome diameter” (DA) is 4.0 mm.

  Further, the upper sheet 17 is made of PET (polyethylene terephthalate), and “Model Number; HSL” manufactured by Teijin DuPont Films Ltd. is used. The thickness E of the upper sheet 17 is 0.1 mm. The height F of the dot portion 15 is 0.2 mm, and the material of the dot portion 15 is a UV curable resin.

  Moreover, as a manufacturing method of the switch apparatus 1 of Example 1, printing for a design was performed on the back surface side (lower side in FIG. 2) of the upper sheet 17, and further UV printing resin was printed and 0.2 mm. A dot portion 15 having a height F is created.

  Further, the switch dome 7 is disposed at a predetermined position of, for example, the substrate 3 as a printed wiring board manufactured by a known method. A dome presser sheet 9 is attached from above the switch dome 7 and the substrate 3. At this time, the light emitter 13 is connected to the substrate 3. Further, for example, a double-sided adhesive sheet as the spacer 11 is affixed on the dome presser sheet 9. The spacer 11 is provided with a hole 11A in accordance with the position of each dome presser sheet 9.

  Next, as described above, the upper sheet 17 provided with the dot portions 15 is bonded from above the dome presser sheet 9 and the spacer 11 on the substrate 3, thereby creating a test sample of the switch device 1 of Example 1. Is done. The finished thickness H at this time, that is, the total thickness G from the substrate 3 to the upper sheet 17 is 0.8 mm.

  In this embodiment, “the thickness of the switch portion” means a thickness at a position passing through the apex portion of the switch dome 9, and corresponds to the total thickness G. Further, “the thickness of the spacer portion” means the thickness H in the spacer portion. In Example 1, the difference (G−H) between “the thickness of the switch portion” and “the thickness of the spacer portion” is 0.2 mm.

  Further, the distance J from the outer peripheral edge of the switch dome 7 (herein, “metal dome edge”) to the light emitter 13 is 1.0 mm.

[Example 2]
As a constituent material of the switch device 1 of Example 2, the height F of the dot portion 15 is 0.1 mm, and the difference (GH) between the “switch portion thickness” and the “spacer portion thickness”. Is 0.0 mm. The rest is the same as in the first embodiment. Therefore, the finished thickness H (total thickness) is 0.6 mm.

Example 3
As a constituent material of the switch device 1 of the third embodiment, the height F of the dot portion 15 is 0.5 mm, and the difference between the “switch portion thickness” and the “spacer portion thickness” (GH). Is 0.5 mm. The rest is the same as in the first embodiment. Therefore, the finished thickness H (total thickness) is 1.0 mm.

Example 4
As a constituent material of the switch device 1 according to the fourth embodiment, the material of the dot portion 15 is silicon rubber. Therefore, the finished thickness H (total thickness) is 0.8 mm.

Example 5
As a constituent material of the switch device 1 of the fifth embodiment, the material of the dot portion 15 is a thermosetting epoxy resin, and the other components are the same as those of the first embodiment. Therefore, the finished thickness H (total thickness) is 0.8 mm.

Example 6
As a constituent material of the switch device 1 of the sixth embodiment, the spacer diameter D is 5 mm, and the “spacer diameter” − “metal dome diameter” (DA) is 1 mm. The rest is the same as in the first embodiment. Therefore, the finished thickness H (total thickness) is 0.8 mm.

Example 7
As a constituent material of the switch device 1 of Example 7, the spacer diameter D is 20 mm, and the “spacer diameter” − “metal dome diameter” (DA) is 16 mm. The rest is the same as in the first embodiment. Therefore, the finished thickness H (total thickness) is 0.8 mm.

Example 8
As a constituent material of the switch device 1 of the eighth embodiment, the distance J from the outer peripheral edge of the switch dome 7 to the light emitter 13 is 0.5 mm, and the other configuration is the same as the first embodiment. Therefore, the finished thickness H (total thickness) is 0.8 mm.

Example 9
As a constituent material of the switch device 1 of the ninth embodiment, the distance J from the outer peripheral edge of the switch dome 7 to the light emitter 13 is 4.5 mm, and the rest is the same as the first embodiment. Therefore, the finished thickness H (total thickness) is 0.8 mm.

[Comparative Example 1]
As a constituent material of the switch device of Comparative Example 1, the dot portion 15 is not printed on the upper sheet 17. The difference (GH) between “the thickness of the switch part” and “the thickness of the spacer part” is −0.05 mm. The rest is the same as in the first embodiment. Therefore, the finished thickness H (total thickness) is 0.55 mm.

[Comparative Example 2]
As a constituent material of the switch device of Comparative Example 2, the height F of the dot portion 15 is 0.8 mm, and the difference (G−H) between “the thickness of the switch portion” and “the thickness of the spacer portion” is 0.8 mm. The rest is the same as in the first embodiment. Therefore, the finished thickness H (total thickness) is 1.4 mm.

[Comparative Example 3]
As a constituent material of the switch device of Comparative Example 3, the spacer diameter is 4.5 mm, and “spacer diameter” − “metal dome diameter” (DA) is 0.5 mm. The rest is the same as in the first embodiment. Therefore, the finished thickness H (total thickness) is 0.8 mm.

[Comparative Example 4]
The switch device of Comparative Example 4 has the conventional structure shown in FIG. The thickness of the key mat 113 is 2.0 mm. The finished thickness H (total thickness) is 2.5 mm.

[Comparative Example 5]
As a constituent material of the switch device of Comparative Example 5, the distance J from the outer peripheral edge of the switch dome 7 to the light emitter 13 is 5.0 mm, and other than this is the same as Example 1. Therefore, the finished thickness H (total thickness) is 0.8 mm.

  Next, samples of the switch devices 1 of the above-described Examples 1 to 9 and Comparative Examples 1 to 5 were prepared, and click rate, durability, and luminance tests were performed on each sample. The test results of “Table 1” and “Table 2” were obtained.

  As a test method of the click rate, as shown in FIG. 3, a load-displacement curve when the switch dome 7 is pushed is shown. The operational feel is evaluated by a maximum value load (P1), a minimum value load (P2), and a stroke (S2). Specifically, the pushing force is evaluated by the maximum value P1, the buckling feeling is evaluated by the click rate [= (P1-P2) / P1], and the pushing depth is evaluated by S2. In general, it is known that the higher the click rate, the better the feel (= good click characteristics).

  Then, the click rate was evaluated using the commercially available load displacement measuring device with respect to the samples of Examples 1 to 9 and Comparative Examples 1 to 5. The number of samples was N = 100, and the average value was used.

  In addition, as a durability test method, 500,000 keystroke tests were performed on the samples of Examples 1 to 9 and Comparative Examples 1 to 5 using a keystroke tester. The number of samples was N = 50, and the condition of the sample after the test, specifically peeling, rubbing, misalignment, and continuity on the appearance was judged and judged. .

Moreover, as a luminance test method, the luminance was evaluated using “CS-100” manufactured by Konica Minolta on the samples of Examples 1 to 9 and Comparative Examples 1 to 5. Regarding luminance, 3.0 cd / m ² or more was regarded as acceptable.

  As can be seen from Table 1, when the difference (G−H) between “the thickness of the switch portion” and “the thickness of the spacer portion” is smaller than 0 μm, for example, as shown in Comparative Example 1, the click rate Is unsuitable because it decreases. Conversely, when the difference (G−H) between “the thickness of the switch portion” and “the thickness of the spacer portion” is greater than 0.5 mm, the keystroke durability decreases as shown in Comparative Example 2. . The reason for this is that positional deviation between the dot portion 15 and the switch dome 7 is likely to occur due to keystroke. Therefore, the difference (GH) between the “switch portion thickness” and the “spacer portion thickness” is preferably 0 mm or more and 0.5 mm or less.

  The dot portion 15 attached to the upper sheet 17 can be used in any of the UV curable resin, thermosetting resin, and silicon rubber used this time, and the material of the dot portion 15 is not particularly limited. Moreover, the manufacturing method of the dot part 15 may be a coating method, a curing method, an adhesion method, or the like, and is not particularly limited.

  The inner diameter D (spacer diameter) of the annular portion 11B of the spacer 11 is preferably 0.5 mm or more than the diameter A (metal dome diameter) of the switch dome 7. As shown in Comparative Example 3, when it is smaller than 0.5 mm, the click rate decreases.

  Although there is no restriction | limiting in particular in the installation location of the spacer 11, in order to prevent malfunction of a key, it is more preferable to install between the upper sheet | seat 17 and the dome holding sheet | seat 9. FIG.

  Using a flexible printed circuit board (FPC) is more advantageous for reducing the total thickness of the switch device 1, but a rigid printed circuit board (RPC) can also be used. There is no particular restriction.

  In Comparative Example 4, the total thickness is too thick as compared with Examples 1 to 9, and is not suitable for thinning.

Further, the distance J from the outer peripheral edge of the switch dome 7 to the light emitter 13 is preferably 0.5 mm or more and less than 5 mm. As shown in Comparative Example 5, the luminance decreases when the distance J is 5.0 mm. In addition, light emission of the switch apparatus 1 of Example 1- Example 9 is 3.0 cd / m < ² > or more, and it turned out that the same light emission is possible without being inferior to a conventional thing.

  From the above, the switch device 1 according to this embodiment does not use the key mat 113 as in the prior art, and has the upper sheet 17 having the dot portion 15 facing the apex of the switch dome 7 and the upper sheet. By adopting a structure using the spacer 11 having a hole 11A arranged so as to surround the switch dome 7 below the switch 17, the total thickness can be reduced to 1 mm or less. It can be easily stored in the electronic device. Moreover, it has excellent characteristics such as click rate and durability. In addition, the light of the illuminant can be irradiated and reflected on the dome presser sheet 9 on the switch dome 7 although the thickness can be reduced as described above.

It is a fragmentary sectional view of the switch device of an embodiment of this invention. It is a top view when the upper sheet | seat of FIG. 1 is removed. It is a load displacement curve figure at the time of pushing the dome for switches. It is a fragmentary sectional view of the conventional switch apparatus.

Explanation of symbols

1 Switch device 3 Board (printed wiring board)
5A, 5B Contact point 7 Switch dome 9 Dome presser sheet 9A Sheet material (light diffusion sheet)
9B Adhesive layer 11 Spacer 11A Hole 11B Notch 13 Light emitter 15 Dot 17 Upper sheet

Claims (5)

A switch dome made of a flexible bowl-shaped conductive material which is arranged so as to cover the contact portion on the substrate substantially at the center and which can be contacted and separated from the contact portion;
A light-reflective dome presser sheet that places and holds the switch dome at a predetermined position on the substrate;
An upper sheet having a dot portion facing the apex of the switch dome;
A spacer having a hole disposed around the switch dome below the upper sheet;
A light emitter that is disposed between the upper sheet and the dome presser sheet and irradiates the dome presser sheet;
A switch device comprising:   The switch device according to claim 1, wherein a total thickness from the substrate to the upper sheet is 1 mm or less.   The difference between the thickness of the switch part from the substrate passing through the apex of the switch dome to the surface of the upper sheet and the thickness of the spacer part from the substrate located on the spacer to the surface of the upper sheet is 0 mm or more, The switch device according to claim 1, wherein the switch device is 0.5 mm or less.   4. The switch device according to claim 1, wherein an inner diameter of the hole of the spacer is 0.5 mm or more larger than a diameter of the dome for the switch.   4. The switch device according to claim 1, wherein the light emitter is disposed at a position of 0.5 mm or more and less than 5 mm from an outer peripheral edge of the switch dome.

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