JPH0621149Y2 - Key top sheet for membrane switch - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a key top sheet for a membrane switch in which a pressing operation projection is integrally formed on the surface of an operation panel.

[Conventional technology]

BACKGROUND ART Conventionally, as a key top sheet for forming a pressing operation projection on a surface thereof, there is provided a key top sheet in which the pressing operation projection is fitted to a surface sheet.

[Problems to be solved by the device]

In the above-mentioned conventional key top sheet, the pressing operation projections that are manually operated are molded separately, so a mold for molding the pressing operation projections is required.

Further, the formed pressing operation projection has an additional work of fitting on the surface sheet, and there is a problem that the number of steps increases in proportion to the number of pressing operation projections. Further, since there is a problem such as falling off depending on the accuracy of the fitting portion of the pressing operation projection, processing with high accuracy is required. On the other hand, the operation surface including the pressing operation projection is printed with an arbitrary design, and each component is printed in different colors and different characters, which further increases the number of steps. As a result, the cause of a decrease in yield due to defective printing increases, and there is a drawback when the cost becomes high. Further, not only the wall thickness of the formed pressing operation projection is thick, but also the surface sheet to which the pressing operation projection is fitted must be thickened to prevent the surface sheet from falling off. Therefore, when the pressing operation force of the key top sheet becomes heavy and it becomes difficult to obtain a good tactile sensation, there is a drawback. In addition, when used in the operation of a sheet-shaped membrane switch, due to the shape of the key top sheet, assembly, etc., the failure rate was high even when it remained closed.

The present invention eliminates such drawbacks, and an object of the present invention is to provide an inexpensive key top sheet for a membrane switch, which is easy to operate.

[Means for Solving the Problems]

In order to achieve the above object, in the present invention, a pushing operation projection 1 that is operated artificially is formed by embossing, and a spacer 8 and a switch pushing portion 10 are provided between a back sheet 4 and a membrane switch 11. To do.

That is, a thin surface sheet 2 having a pressing operation projection 1 on the front surface and a recess 12 on the back surface by embossing,
A thin backsheet 4 that is attached to the back surface of the topsheet 2 and has a through hole 3 through which air passes in a position facing the center of the recess 12 and a space 5 formed between the backsheet 4 and the recess 12. The spacer 6 made of a thin sheet having a filler 6 to be attached, and a notch 7 that is largely cut out so as not to overlap the space 5 around the through hole 3 on the back sheet 4 side and a spacer inside the notch 7. Has the same thickness as 8,
It is composed of an annular switch pressing portion 10 having an inner circumference 13 which is slightly larger than the outer edge 9 of the space 5.

Further, the switch pressing portion 10 may be integrally formed so as to be bridged with the spacer 8.

Further, the spacer 8 and the switch pressing portion 10 may be attached to the upper surface of the backsheet 4.

[Action]

In the present invention, the pressing operation projection 1 is formed on the thin surface sheet 2 by embossing, and the filling material 6 is sealed between the recess 12 formed on the back surface of the pressing operation projection 1 and the back sheet 4. It has increased rigidity.

According to the key top sheet of the present invention, the pressing operation projection 1 is formed integrally with the topsheet 2, and the operation feeling of the pressing operation projection 1 is arbitrarily adjusted by the shape, the material of the filling material 6 and the like. it can.

Further, the through hole 3 prevents the peeling of the back sheet 4 from sticking because the air pressure in the space 5 becomes excessive due to the temperature change and the pressing force applied to the pressing operation projection 1. The spacer 8 slightly separates the back sheet 4 and the membrane switch 11 from each other, so that the key top sheet or the membrane switch 11 is deformed when attached, the filler 6 is contracted and deformed when it is loaded, and the membrane switch 11 is unintentionally pressed. Prevent closure.

The switch pressing portion 10 is provided in the notch portion 7 of the spacer 8 and distributes the pressing force applied to the membrane switch 11 to the outer edge 9 from the pressing operation projection portion 1, and the membrane switch 11
This is a stable operation.

〔Example〕

 The present invention will be described in detail below with reference to the drawings.

FIG. 1 is a sectional view showing a key top sheet for a membrane switch of the present invention.

The topsheet 2 is composed of a laminate material in which a printing layer 14 for graphic color printing or the like is arranged between a material 15 to be printed made of transparent polyester or polycarbonate and a reinforcing sheet material 16 made of PET or the like.

As a matter of course, the reinforcing sheet material 16 having a single-sided adhesive is used and adhered to the printing layer 14. The surface sheet 2 is formed with a pressing operation projection 1 on the front surface 20a and a recess 12 on the opposite back surface 20b by embossing. The back sheet 4 made of a PET film or the like is adhered to the reinforcing sheet material 16 which is the back surface 20b of the top sheet 2. Further, at a position facing the center of the recess 12 of the topsheet 2, a through hole 3 serving as an air inlet / outlet of the backsheet 4 is provided, and the recess 1
The pressure of the air in the space 5 formed by the back sheet 4 and the back sheet 4 is kept equal to the outside air, and the deformation of the pressing operation projection 1 due to the air pressure and the peeling between the top sheet 2 and the back sheet 4 do not occur. To be done.

A filler 6 made of PET, acrylic, silicone rubber, epoxy, UV, gel or the like is sealed in the space 5 and transmits an artificial pressing force to the pressing operation projection 1 to the back sheet 4. By changing the hardness range by selecting the filler 6, it is possible to adjust the feeling of operation in combination with the flexibility of the key top sheet.

Further, with respect to the filling material 6, it is possible to eliminate the need to make a special molding die by filling the liquid material with the recess 12 as a die. The spacer 8 separates the key top sheet from the membrane switch 11 which is closed by the pressing operation of the key top sheet, and provides a notch 7 larger than the outer edge 9 of the recess 12 formed in the top sheet 2. , A gap corresponding to the thickness of the spacer 8 is formed, and as shown in FIGS. 2a and 2b, the filler 6 is deformed at the time of unexpected solidification, so that the backsheet 4 is located at the center or the outer peripheral side of the space 5. When the membrane switch 11 is attached to the membrane switch 11, the protrusion is formed so that it is not closed regardless of the operation.

3a and 3b are layout explanatory views of the spacer 8 and the switch pressing portion 10. In FIG. 3 a, the switch pressing portion 10 is provided in the notch portion 7 of the spacer 8 and the outer edge 9 of the recess 12 formed in the back surface 20 b of the topsheet 2.
It is arranged further outside and is configured so as not to be affected by the deformation of the back sheet 4 by the filler 6.

FIG. 3b shows that the spacer 8 and the switch pressing portion 10 are integrally formed by the same sheet and are bridged with connecting portions 17 on all four sides, which facilitates the molding of the key top sheet or the assembling of the membrane switch 11. It is something to do. Of course, the spacer 8 and the switch pressing portion 17
Is disposed on the back sheet 4.

[Effect of device]

According to the present invention, the pressing operation projection 1 that serves as a switch operation portion is formed by embossing the surface sheet 2, and the conventional pressing operation projection 1 single die and Assembling work is unnecessary and inexpensive key top sheets can be supplied. In addition, the space 5 of the key top sheet
Depending on the selection of the filler 6 to be sealed to the
It is possible to manufacture key tops that are easy to operate. Further, by providing the spacer 8 on the upper surface of the membrane switch 11, the key top sheet and the membrane switch 11 are separated from each other, and the membrane switch 11 is closed accidentally due to the careless deformation of the membrane switch 11 and the deformation at the time of solidification of the filling material 6. Therefore, it is effective in eliminating the occurrence of defects.

Further, by providing the switch pressing portion 10 in the cutout portion 7 of the spacer 8, there is an effect that the membrane switch 11 can be stably closed by the pressing operation of the pressing operation projection 1.

[Brief description of drawings]

FIG. 1 is a cross-sectional explanatory view of a key top sheet for a membrane switch of the present invention. FIG. 2 is an explanatory view of a modified example of the molding of the filling material 6, and FIG. 3 is an explanatory view of the arrangement of the spacer 8 and the switch pressing portion 10. 1 ... Pressing operation protrusion, 2 ... Surface sheet 3 ... Through hole, 4 ... Back sheet 5 ... Space, 6 ... Filler 8 ... Spacer, 10 ... Switch pressing section 11 ... Membrane switch

Claims (3)

[Scope of utility model registration request] 1. A thin surface sheet having a pressing operation projection on the front surface and a recess formed on the back surface by embossing, and a thin sheet adhered to the back surface of the surface sheet to pass air to a position facing the center of the recess. A thin backsheet having through holes,
A filling material sealed in a space formed between the back sheet and the recess, and a notch that is largely cut out so as not to overlap the space around the through hole on the back sheet side. A spacer made of a thin sheet having a portion, and an annular switch pressing portion having the same thickness as the spacer inside the cutout portion and forming an inner circumference slightly larger than the outer edge of the space portion, A key top sheet for a membrane switch, characterized in that a sheet-shaped membrane switch is closed by pressing a protrusion for pressing operation. 2. The key top sheet for a membrane switch according to claim 1, wherein the switch pressing portion is integrally formed so as to bridge the spacer. 3. The key top sheet for a membrane switch according to claim 1, wherein the spacer and the switch pressing portion are attached to the upper surface of the back sheet.