JPH025316A - Membrane switch and its manufacture - Google Patents

Abstract

PURPOSE:To realize a thin form and a low cost by arranging a click plate in a dome-form on the surface of an electrode sheet, and superposing the periphery of a hole formed on a fixed sheet contacted to the surface of the electrode sheet to the periphery of the click plate. CONSTITUTION:A spacer in a conventional membrane switch is omitted, and a fixed sheet 8 is connected directly on the surface of an electrode sheet 4, while a click plate 5 is to be held by the fixed sheet 8. The thickness of the fixed sheet 8 is made about 50mum. The whole rear side of the fixed sheet 8 is connected to the surface of a sheet 1a, and to the sheet 8, a hole 9 whose diameter is smaller than the outer diameter of the click plate 5 is formed, while the sheet 8 is contacted to the surface of the click plate 5 on condition that the periphery 9a of the hole 9 is superposed on the periphery 5a of the click plate 5. And around the hole 9 formed on the sheet 8, a hole 10 for ventilation striding on the sheet 4 and the periphery 5a of the click plate 5 is formed.

Description

DETAILED DESCRIPTION OF THE INVENTION "Field of Industrial Application" The present invention relates to a membrane switch used in a keyboard or the like to open and close an electric circuit, and a method for manufacturing the same.

``Prior Art'' Conventionally, membrane switches have been known in which printed patterned contacts are provided on a flexible sheet (membrane), examples of which are shown in FIGS. 6 and 7.

The membrane switch shown in these figures consists of a sheet 1 made of flexible insulating resin (for example, polyester resin). , lb
are laminated with spacers 2 interposed therebetween, and electrodes 3.3 are provided on the mutually opposing surfaces of each sheet la, lb. A click plate 5 is positioned above the electrodes 3 on the upper surface side of the electrode sheet 4. A spacer 6 having a thickness approximately equal to the height of the click board 5 is arranged around the click board 5, and a flexible decorative sheet 7 is adhered to the surface of the spacer 6.

The click plate 5 is made of an elastic material (for example, spring steel) and is elastically deformable, and is circular in plan view as shown in FIG. 7, and as shown in FIG. It has a dome shape that curves away from the electrode sheet 4 toward the center.

In the above-mentioned conventional membrane switch, as shown in FIG. 6(B), when the click plate 5 is pressed with a predetermined force or more from the front side of the decorative sheet 7, the click plate 5 is elastically deformed and reversed. As a result, the sheet 11 is pushed down and the electrodes 3.3 come into contact, and the circuit connected to these electrodes 3.3 becomes "closed".

In addition, such a membrane switch can be made thinner than the various conventional switches, requires fewer parts, and, moreover, the click plate 5 only flips when it is pressed with more than a predetermined force. This has the advantage that a so-called click sensation can be obtained and reliable operation can be performed.

"Problem to be Solved by the Invention" Incidentally, it is desirable for the membrane switch described above to be as thin as possible, but in the conventional membrane switch described above, the thickness is approximately equal to the height of the click plate 5. Since the spacer 6 is provided between the electrode sheet 4 and the decorative sheet 7, the thickness of the entire switch increases by the thickness of the spacer 6.

Furthermore, mounting the click board 5 onto the electrode sheet 4 is not necessarily easy, and requires troublesome work and a considerable amount of work time. It also became an obstacle.

This invention was made in view of the above circumstances, and its purpose is to provide a membrane switch that is thinner, easier to manufacture, and can reduce costs, and a method for manufacturing the same. .

"Means for Solving the Problems" The membrane switch of the present invention comprises a pair of insulating resin sheets laminated at intervals, and a pair of electrodes provided on opposing surfaces of the sheets. A click plate is arranged on the surface of the electrode sheet, and the click plate is held by a fixed sheet adhered to the surface of the electrode sheet, and the click plate is elastically deformable. The material is formed into a dome shape that is approximately circular in plan view and curves away from the electrode sheet from the periphery to the center, and the back surface of the fixed sheet is adhered to the surface of the electrode sheet. In addition, a hole having a diameter smaller than the outer diameter of the click board is formed in this fixing sheet, and the peripheral part on the back side of the hole is overlapped and bonded to the peripheral part on the front side of the click board. It is characterized by the fact that

Preferably, a hole is formed around the hole formed in the fixing sheet to vent air across the electrode sheet and the click plate.

In addition, in the method for manufacturing a membrane switch of the present invention, the click plate is adhered to a fixing sheet, and then the fixing sheet is adhered to the electrode sheet. By positioning and overlapping a jig sheet with holes of the same diameter on the back side of the fixing sheet, the periphery of the back side of the hole formed in the fixing sheet can be aligned with the hole formed in the jig sheet. The click plate is exposed on the inside, and the outer peripheral edge of the click board is pressed against the periphery of the exposed hole in the fixed sheet through the hole formed in the jig sheet to be bonded. It is something.

"Embodiments" Examples of the present invention will be described below with reference to FIGS. 1 to 5. Note that parts common to the conventional membrane switch described above are given the same reference numerals to simplify the description.

Figure m1 is a sectional view showing a schematic configuration of a membrane switch according to an embodiment of the present invention, and Figure 2 is a plan view thereof. In the membrane switch of this embodiment, the spacer 6 in the conventional membrane switch shown in FIG.
The fixing sheet 8 holds a click plate 5 similar to the click plate 5 in a conventional membrane switch.

The fixing sheet 8 may be the same as the conventional decorative sheet 7, but it can also be made of, for example, inexpensive polyethylene terephthalate (PET) resin, and if it is too thick, the click feeling will be impaired. If it is too thin, it may not be possible to secure the fixing strength of the click plate 5, so it is preferable to set it to about 50 μm. The entire back surface of the fixed sheet 8 is adhered to the surface of the sheet is, and a hole 9 with a smaller diameter than the outer diameter of the click plate 5 is formed in the fixed sheet 8. and the peripheral part 9a of the hole 9 is the peripheral part 5a of the click plate 5.
It is designed to be glued to the surface while being superimposed on the surface.

Furthermore, a hole 10 having a smaller diameter than the hole 9 is formed in the vicinity of the hole 9 formed in the fixed sheet 8 . This hole 10 is located in such a position that it spans both the periphery M+ 5a of the click board 5 and the sheet 11 of the electrode sheet 4 when the fixed sheet 8 is adhered to the sheet 18 and the periphery 5a of the click board 5. It is provided as an air vent for letting air escape from the inside to the outside when the click board 5 is pressed and reversed.

In the membrane switch with the above configuration, the number of parts is reduced by omitting the spacer 6 in the conventional membrane switch, and the work to attach the spacer 6 can be omitted, so the manufacturing cost can be reduced accordingly. can be achieved. In addition, in this membrane switch, although the click plate 5 is raised above the electrode sheet 4, the overall thickness can be made thinner than that of a conventional membrane switch by omitting the spacer 6, making it suitable for a wide range of applications. This makes it possible.

In this membrane switch, the peripheral edge 5 of the click plate 5 is attached to the fixed sheet 8! An air vent hole 10 is provided across both the and seat 11, and internal air leaking when the click plate 5 is reversed is allowed to escape through the hole 10, so that there is no rebound due to an increase in internal air pressure.
Therefore, reliable opening/closing operations can be performed, and the same operating feeling as a conventional membrane switch can be obtained.

In addition, in conventional membrane switches, the click plate 5 is hidden behind the decorative sheet 7, so it is necessary to display some kind of display on the surface of the decorative sheet 7 to indicate the presence of the click plate 5. In the membrane switch of this embodiment, since the click plate 5 is raised and exposed, the click plate 5 has the advantage that its position is naturally clear without any special display.

Note that it may be possible to cover the entire upper surface of the click board 5 with the fixing sheet 8 without providing the holes 9 in the fixing sheet 8, but in such a case, the fixation at the peripheral edge 5a of the click board 5 may be There is a risk that the sheet 8 may lift up or wrinkle, and in that case, the fixed sheet 8 deforms together with the switch operation and the click plate 5, causing it to sag during long-term use. It's scary and unrealistic. In this respect, in the membrane switch of this embodiment, the fixing sheet 8 is provided with a hole 9, and only the peripheral portion 9a of the hole 9 is provided at the peripheral edge 5 of the click plate 5! There is no such fear because the material is bonded to the surface.

Next, the procedure for mounting the click board 5 onto the electrode sheet 4 will be explained with reference to FIGS. 3 and 4.

These figures show a large number (eight in the illustrated example) of click boards 5.
. . , in a desired arrangement at once. Note that in these figures, illustration of the holes 10 formed in the fixed sheet 8 is omitted.

In this case, a workbench 16 having a rubber sheet 15 attached to its upper surface and a jig sheet 17 for positioning the click plates 5 are used. The jig sheet 17 has holes 18 having a diameter approximately equal to the outer diameter of the click plate 5, that is, a diameter larger than the holes 9 formed in the fixed sheet 8, in a desired arrangement. It is a resin sheet (thickness is preferably about 1 mm in diameter) formed into a shape, and a release paper 19 is adhered to the back side of the sheet.

First, as shown in FIG. 4(a), the holes 9 and
... is formed in the same arrangement as the holes 18 in the jig sheet 17 described above, by applying an adhesive over the entire top surface of the fixing sheet 8 with its back side facing the top side, Place it on the rubber sheet 15 on the workbench 16,
Place the jig sheet 17 on top of the fixed sheet B,
Temporarily glue them together.

At this time, the holes 9 of the fixed sheet 8 and the jig sheet 1
A positioning member 20 is installed upright from the workbench 16 so that each 18 formed in the
．． 20 (see FIG. 3) to position both. As a result, the peripheral portions 9a on the back side of the holes 9 of the fixed sheet 8 are exposed inside the holes 18 of the jig sheet 17.

Then, as shown in FIGS. 3 and 4, the click board 5 is turned upside down (that is, curved downward), and the click board 5 is exposed inside the hole 18 through the hole 18. Press against the peripheral part 9& of the hole 9 of the fixing sheet 8. As a result, as shown in FIG. 4(B), the peripheral edge 5a on the front side of the click board 5 is pressed against the peripheral edge 9a on the back side of the hole 9 of the fixing sheet 8, and these are applied to the upper surface of the fixing sheet 8. It is attached with the adhesive that was used. Note that when the click board 5 is pressed, the rubber sheet 15 deforms and the center part of the click board 5 becomes the rubber sheet 1.
Since the click plate 5 is slightly sunk into the inside of the click plate 5, the click plate 5 is not deformed or damaged.

After pasting all the click plates 5 to the fixing sheet 8 through the holes 1B as described above, work the fixing sheet 8 with the click plates 5 attached together with the jig sheet 17. Remove from the table 16 and jig sheet 17
is peeled off from the fixed sheet 8. At this time, the jig sheet 17
Since the release paper 19 is adhered to the back surface of the jig sheet 17, the jig sheet 17 can be easily peeled off. by this,
The click boards 5 are left bonded to the fixing sheet 8 as shown in FIG. 4(c). Further, the adhesive remains on the upper surface of the fixing sheet 8 as it is.

Therefore, this fixed sheet 8 is reversed, and each click board 5 is
The electrodes 3.3... are positioned and stacked on the electrode sheet 4 on which the electrodes 3, 3... are provided in the same arrangement as the arrangement, and the fixing sheet 8 is pressed onto the surface of the electrode sheet 4, and the above adhesive is applied. If they are adhered as is, each click board 5 is mounted on the electrode sheet 4, and a membrane switch is completed.

According to the above procedure, the click board 5 can be accurately positioned with respect to the fixed sheet 8, and a large number of click boards 5 can be mounted at once in a desired arrangement, resulting in excellent workability. Therefore, the working time can be greatly shortened, and together with omitting the spacer 6, the manufacturing cost can be significantly reduced.

In the above embodiment, a hole 10 is provided in the fixing sheet 8 as an air vent to remove air from inside the click board 5; however, even if the hole 10 is not provided, air will naturally leak out and the click board If it is expected that 5 will be easily reversed, they may be omitted. For example, the fixing sheet 8 may not be bonded to the peripheral edge 5a of the click board 5 over the entire circumference of the click board 5, but may be bonded partially at intervals in the circumferential direction of the click board 5. In other words, an example is shown in FIG. As shown in the figure, if the hatched parts are closed at the adhesive portions 20 and the click board 5 and the fixing sheet 8 are bonded together using only those adhesive portions 20, the click board 5 will be deformed. When it is turned over, air can be expected to be pushed out and leak from the non-bonded parts.

In addition, when the hole 10 is provided, a hole may also be provided in the peripheral portion 5a of the click plate 5 exposed through the hole IO, and air may be allowed to escape through the hole and the hole 10 described above.

Also, in the mounting procedure described above, when adhering each click board 5 to the fixing sheet 8, the adhesive is not applied to the entire surface of the fixing sheet 8, but the area around the holes 9... 9
a...or the periphery 5 of the click board 5...!・・・
・Only apply adhesive to the entire surface of the fixing sheet 8 when adhering the fixing sheet 8 to which the click board 5 is attached to the electrode sheet 4. Appropriate changes can be considered, such as applying the same (in this case, the release paper 19 provided on the back surface of the jig sheet 17 can be omitted).

"Effects of the Invention" As explained in detail above, in the membrane switch of the present invention, a dome-shaped click plate is arranged on the surface of the electrode sheet, and the click plate is formed on a fixed sheet that is adhered to the surface of the electrode sheet. The click board is held by overlapping and bonding the surrounding area of the hole to the periphery of the click board, so it is not only possible to perform reliable operation by reversing the click board, but it is also possible to The spacer in the membrane switch is omitted, resulting in a thinner and cheaper membrane switch.

Furthermore, if a hole is provided around the hole in the fixed sheet for air venting, air can be reliably released from inside when the click board is pressed and turned over.
This has the effect of preventing repulsion due to an increase in internal air pressure, allowing reliable opening/closing operations, and providing the same operational feel as a conventional membrane switch.

Further, according to the manufacturing method of the present invention, after the click board is bonded to the fixed sheet, the fixed sheet is bonded to the electrode sheet, and the click board is bonded to the fixed sheet. , a jig sheet with a hole approximately the same diameter as the click board and a fixing sheet are overlapped to expose the periphery of the hole in the fixing sheet to the inside of the hole in the jig sheet, and the fixing sheet is exposed. Since the click plate is pressed and bonded to the periphery of the hole, the jig sheet allows accurate positioning of the click plate with respect to the fixing sheet, and also makes it possible to mount a large number of click plates at once. This has the effect of reducing the number of parts and reducing the manufacturing effort, thereby reducing the manufacturing cost.

[Brief explanation of the drawing]

1 to 5 show embodiments of this invention,
FIG. 1 is a sectional view showing a schematic configuration of a membrane switch according to an embodiment, FIG. 2 is a plan view thereof, and FIG. 3 is a perspective view for explaining the mounting process of a click board in the above embodiment.
4(a) to 4(c) are sectional views showing the mounting procedure in the order of steps, and FIG. 5 is a plan view of a click board of another embodiment. 6 and 7 show a conventional membrane switch, in which FIG. 6(a) is a sectional view showing its schematic structure, FIG. 6(b) is a sectional view in a pressed state, and FIG. It is a view taken along the line ■-■ in FIG. 6(a). 1i, lb...sheet, 3...electrode,
4...Electrode sheet, 5...Click board, 5m--periphery of click board, 8...Fixing sheet, 9...hole, 9a ...Peripheral part of the hole, 10 ...hole, 15 ... rubber sheet, 16 ... workbench, 17 ... jig sheet , 18... hole.

Claims (3)

[Claims] (1) Consisting of a pair of insulating resin sheets (1a, 1b) stacked at intervals, and a pair of electrodes (3, 3) provided on opposing surfaces of these sheets, respectively. A membrane switch in which a click plate (5) is disposed on the surface of an electrode sheet (4), and the click plate is held by a fixing sheet (8) adhered to the surface of the electrode sheet, The click board is made of an elastically deformable material and is formed into a dome shape that is approximately circular in plan view and curved away from the electrode sheet from the peripheral edge (5a) to the center, and the fixed sheet is formed on the back surface of the click board. is adhered to the surface of the electrode sheet, and a hole (9) having a diameter smaller than the outer diameter of the click plate is formed in this fixing sheet, and the peripheral part (9a) on the back side of the hole is formed in the fixing sheet. ) is a membrane switch which is overlapped and bonded to the peripheral edge of the front side of the click board. (2) Holes (9) formed in the fixed sheet (8)
A hole (10) for venting air is formed in a peripheral portion of the electrode sheet (4) and a peripheral portion (5a) of the click plate (5). The membrane switch described in item 1. (3) A fixed sheet (8) is formed on the peripheral edge (5a) on the front side of the dome-shaped click plate (5) placed on the surface of the electrode sheet (4) to be adhered to the surface of the electrode sheet. A method for manufacturing a membrane switch in which a click plate is held by the fixing sheet by overlapping and bonding the peripheral part (9a) on the back side of the hole (9), the method comprising:
After the click board was bonded to the fixed sheet, the fixed sheet was bonded to the electrode sheet, and when the click board was bonded to the fixed sheet, a hole (18) having approximately the same diameter as the click board was formed. By positioning and overlapping the jig sheet (17) on the back side of the fixing sheet, the peripheral part (9a) on the back side of the hole (9) formed in the fixing sheet is formed in the jig sheet. Hole (1
8), and press the periphery of the front side of the click board through the hole formed in the jig sheet against the periphery of the exposed fixing sheet hole to adhere it. A method for manufacturing a membrane switch.