JP6892762B2 - Push button switch member and its manufacturing method - Google Patents

Description

The present invention relates to a member for a push button switch and a method for manufacturing the same.

As switches for a wide variety of devices such as in-vehicle devices, communication devices, audio devices, and household electric appliances, push button switch members having a pressing portion, a thin-walled movable portion, and a base portion (see, for example, Patent Documents 1 and 2) are used. The one used is known.

FIG. 11 shows a vertical cross-sectional view of a conventionally known push button switch member 101. The push button switch member 101 includes a pressing portion 110, a thin-walled movable portion 120 connected to the outer circumference of the pressing portion 110, and a base portion 130 connected to the outer circumference of the thin-walled movable portion 120. The push button switch 101 further includes a protruding portion 112 that projects downward from the lower surface of the pressing portion 110. The pressing portion 110 projects to one side (may be referred to as an upper side or a front side) with reference to the base portion 130. Further, the pressing portion 110, the thin-walled movable portion 120, and the base portion 130 are made of the same type of rubber-like elastic body.

Further, FIG. 12 shows a vertical cross-sectional view of another conventionally known push button switch member 102. The push button switch member 102 includes a pressing portion 140, a thin-walled movable portion 150 connected to the outer circumference of the pressing portion 140, and a base portion 160 connected to the outer circumference of the thin-walled movable portion 150. The push button switch 102 further includes a protruding portion 142 projecting downward from the lower surface of the pressing portion 140. The pressing portion 140 projects to one side (may be referred to as an upper side or a front side) with reference to the base portion 160. Further, the pressing portion 140, the thin-walled movable portion 150, and the base portion 160 are made of different rubber elastic bodies on the upper side and the lower side. Specifically, in the pressing portion 140, the thin-walled movable portion 150, and the base portion 160, the upper member 152 is made of a rubber-like elastic body having a higher hardness, and the lower member 154 is made of a rubber-like elastic body having a lower hardness.

According to the conventionally known push button switch members 101 and 102 described above, the thin-walled movable portions 120 and 150 are elastically deformed by downward pressing from the pressing portions 110 and 140 and the release operation thereof. Therefore, the push button switch members 101 and 102 are used as push-type switches.

Japanese Unexamined Patent Publication No. 7-12249 Japanese Unexamined Patent Publication No. 2009-117073

Conventionally known push button switch members 101 and 102 have excellent functions as push button switch members, but there is room for further improvement in order to make them more excellent push button switch members. The details will be described below.

When a downward pressure is applied to the pressing portions 110 and 140 of the push button switch members 101 and 102, the thin-walled movable portions 120 and 150 are deformed, and the pressing portions 110 and 140 are rapidly lowered toward the substrate accordingly. The switch turns on.

If it is desired to change the pressing operation feeling of the push button switch member 101, it is necessary to change the thickness and angle of the thin movable portion 120. However, in order to change the thickness and angle of the thin-walled movable portion 120, it is necessary to modify or remanufacture the molding die. Therefore, in the case of the conventional push button switch member 101, a great deal of labor and cost are required to change the pressing operation feeling.

Further, when it is desired to change the pressing operation feeling of the push button switch member 102, in addition to modifying or remanufacturing the molding die, an upper (front side) and / or lower (back side) rubber-like elastic body is used. Need to change. However, in order to manufacture the push button switch member 102, two types of rubber-like elastic bodies before cross-linking are laminated to form a laminated body, and the laminated body is placed in a heated mold and heat-pressed for cross-linking. .. Since the push button switch member 102 is manufactured by inputting a plurality of materials having different rubber hardness in order to manufacture one product, it takes more time and effort in manufacturing than the push button switch member 101 described above. And costly.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a push button switch member capable of exhibiting a desired pressing operation feeling more easily and at a lower cost.

[1] The push button switch member according to the embodiment for achieving the above object includes a pressing portion, a thin-walled movable portion connected to the outer periphery of the pressing portion, and a base portion connected to the outer periphery of the thin-walled movable portion. , The pressing portion protrudes to one side with respect to the base portion, and the pressing portion, the thin-walled movable portion and the base portion are made of the same type of rubber-like elastic body, and the rubber of at least a part of the thin-walled movable portion is formed. The hardness is higher in the range of 2% to 28% than the rubber hardness in other parts.

[2] In the push button switch member according to another embodiment, a part of the thin-walled movable portion having a higher rubber hardness includes a connecting portion between the thin-walled movable portion and the pressing portion, and a thin-walled movable portion and a base portion. It may be an intermediate region excluding the connecting portion with.

[3] In the push button switch member according to another embodiment, a part of the thin-walled movable portion having a higher rubber hardness may include at least a surface on the side of the pressing portion.

[4] In the push button switch member according to another embodiment, a part of the thin-walled movable portion having a higher rubber hardness may include at least a surface opposite to the pressing portion.

[5] In the push button switch member according to another embodiment, the push button switch member also includes a plurality of pressing portions and thin-walled movable portions, and some portions having a higher rubber hardness are formed into a plurality of thin-walled movable portions. It may be provided at different positions or only in some thin-walled movable parts.

[6] In the push button switch member according to another embodiment, the rubber-like elastic body may also contain silicone rubber.

[7] Further, the method for manufacturing a push button switch member according to an embodiment includes a pressing portion, a thin-walled movable portion connected to the outer periphery of the pressing portion, and a base portion connected to the outer periphery of the thin-walled movable portion, and presses the member. The portion protrudes to one side with respect to the base portion, and the pressing portion, the thin-walled movable portion and the base portion are made of the same type of rubber-like elastic body, and the rubber hardness of at least a part of the thin-walled movable portion is high. It is a method of manufacturing a push button switch member whose hardness is higher than the rubber hardness of other parts in the range of 2% to 28%. The push button switch member is formed by molding the pressing part, the thin-walled movable part and the base part with a rubber-like elastic body. It includes a forming step of forming the element body of the above, and an irradiation step of irradiating at least a part of the thin-walled movable part of the element body with an electron beam to make some parts of the body harder than other parts.

[8] In the method for manufacturing a push button switch member according to another embodiment, further, a part of the thin-walled movable portion having a higher rubber hardness includes a connecting portion between the thin-walled movable portion and the pressing portion and a thin-walled movable portion. An intermediate region excluding the connecting portion between the base portion and the base portion may be used, and the intermediate region may be irradiated with an electron beam in the irradiation step.

[9] In the method for manufacturing a push button switch member according to another embodiment, a part of the thin-walled movable portion having a higher rubber hardness includes at least a surface on the side of the pressing portion, and at least in the irradiation step. The surface on the side of the pressing portion may be irradiated with an electron beam.

[10] In the method for manufacturing a push button switch member according to another embodiment, a part of the thin-walled movable portion having a higher rubber hardness includes at least a surface opposite to the pressing portion, and in the irradiation step, At least the surface opposite to the pressing portion may be irradiated with an electron beam.

[11] In the method for manufacturing a push button switch member according to another embodiment, and in the irradiation step, even if the electron beam is irradiated from both the side surface of the pressing portion and the surface opposite to the pressing portion. good.

[12] In the method for manufacturing the push button switch member according to another embodiment, and in the irradiation step, the irradiation dose of the electron beam may be in the range of 25 kGy to 800 kGy.

According to the present invention, it is possible to provide a push button switch member capable of exhibiting a desired pressing operation feeling more easily and at a lower cost.

FIG. 1 shows a vertical cross-sectional view (1A) and a plan view (1B) of the push button switch member according to the first embodiment, respectively. FIG. 2 shows a flowchart of a method for manufacturing a push button switch member according to the first embodiment. FIG. 3 shows a method of manufacturing a push button switch member according to the first embodiment. FIG. 4 shows a method of manufacturing the push button switch member according to the second embodiment. FIG. 5 shows a vertical sectional view (5A) and a plan view (5B) of the push button switch member according to the third embodiment, respectively. FIG. 6 shows a vertical sectional view (6A) and a plan view (6B) of the push button switch member according to the fourth embodiment, respectively. FIG. 7 shows a vertical sectional view (7A) and a plan view (7B) of the push button switch member according to the fifth embodiment, respectively. FIG. 8 shows a plan view (8A, 8B) of the push button switch member according to the modified example. FIG. 9 shows a vertical cross-sectional view of the element body for the push button switch member used in each Example and each Comparative Example. FIG. 10 shows the evaluation results of each Example and each Comparative Example. A vertical cross-sectional view of a conventionally known push button switch member is shown. A vertical cross-sectional view of another conventionally known push button switch member is shown.

Next, the push button switch member and the manufacturing method thereof according to the present invention will be described with reference to the drawings. It should be noted that each embodiment described below does not limit the invention according to the claims. Moreover, not all of the elements and combinations thereof described in each embodiment are essential for the solution of the present invention. In each embodiment, for components having the same basic configuration and features, the same reference numerals may be used across the embodiments, and the description may be omitted.

(First Embodiment)
First, the push button switch member according to the first embodiment will be described.

FIG. 1 shows a vertical cross-sectional view (1A) and a plan view (1B) of the push button switch member according to the first embodiment, respectively.

As shown in FIG. 1, the push button switch member 1 according to the first embodiment includes a pressing portion 10, a protruding portion 12, a thin-walled movable portion 20, and a base portion 30. The pressing portion 10, the thin-walled movable portion 20, and the base portion 30 are preferably made of the same type of rubber-like elastic body. Further, the pressing portion 10 may be made of a material (any of a rubber-like elastic body, a thermoplastic resin, or a thermosetting resin) different from the material constituting the thin-walled movable portion 20 and the base portion 30. In that case, the pressing support portion located below the pressing portion 10 and connected to the thin-walled movable portion 20 may be formed of the same type of rubber-like elastic body as the thin-walled movable portion 20. In the present application, the pressing support portion can be interpreted as being included in the pressing portion 10 in a broad sense. Therefore, in a form in which the pressing portion 10, the thin-walled movable portion 20, and the base portion 30 are made of the same type of rubber-like elastic body, a hard resin portion is provided above the pressing portion 10 and the rubber-like elasticity is provided below the portion. It may include both a form including a body-made pressing support portion and a form in which the entire pressing portion 10 is made of a rubber-like elastic body. The pressing portion 10, the thin-walled movable portion 20, and the base portion 30 may be separately molded and joined, or may be integrally molded. In the present specification, the meaning of "consisting of the same type of rubber-like elastic body" means that the materials of the rubber-like elastic body before or during molding are the same.

In the first embodiment and other embodiments described later, the rubber-like elastic body preferably includes urethane rubber, isoprene rubber, ethylene propylene rubber, natural rubber, ethylene propylene diene rubber, and nitrile rubber, in addition to silicone rubber. Examples of thermosetting elastomers such as (NBR) or styrene-butadiene rubber (SBR), thermoplastic elastomers such as urethane-based, ester-based, styrene-based, olefin-based, butadiene-based, and fluorine-based, or composites of the above. it can. Among these illustrated rubber-like elastic bodies, silicone rubber is particularly preferable. Further, the rubber-like elastic body may contain a filler such as silica.

The pressing portion 10 projects to one side with reference to the base portion 30. In this embodiment, one side is the upper side or the front side corresponding to the side opposite to the circuit board when the push button switch member 1 is installed on the circuit board or the like. However, in the first embodiment and other embodiments described later, the pressing portion 10 is a cylindrical constituent member having a circular shape in a plan view. Depending on the installation location of the push button switch member 1, it may be referred to in another direction such as the left side or the right side instead of the upper side or the front side. A member made of a thermoplastic resin, a thermosetting resin, a silicone rubber having a hardness higher than that of the pressing portion 10, metal, glass, or the like may be formed on the surface of the pressing portion 10.

The protruding portion 12 is a member that protrudes from the lower side (or back side) of the pressing portion 10 toward the circuit board or the like. When the push button switch member 1 is incorporated into the push button switch, the protruding portion 12 comes into contact with a component (for example, an electrode, a metal dome, or another type of switch) arranged directly under the pressing portion 10 to turn on the switch.・ It becomes a part that can be turned off. The protruding portion 12 is a cylindrical member having a circular plan view shape in the first embodiment and other embodiments described later. The protruding portion 12 may be integrated with the pressing portion 10 or may be a separate body. When the protruding portion 12 is separate from the pressing portion 10, for example, the protruding portion 12 is preferably adhered to the back side of the pressing portion 10. Further, the protruding portion 12 may be made of a conductive substance (for example, a metal or a conductive rubber-like elastic body).

The thin-walled movable portion 20 is a member connected to the outer circumference of the pressing portion 10. The thin-walled movable portion 20 is preferably formed to be thinner than the pressing portion 10 and the base portion 30. The thin-walled movable portion 20 is an elastically deforming member that elastically deforms when the pressing portion 10 is pressed toward a circuit board or the like and returns to its original shape when the pressing on the pressing portion 10 is released.

The rubber hardness of at least a part 22 of the thin-walled movable portion 20 is higher in the range of 2% to 28% than the rubber hardness of the other parts other than the part 22. Here, the rubber hardness refers to the rubber hardness measured by a type A durometer conforming to JIS K 6253. In other figures including FIG. 1, some parts 22 are displayed in light ink (gray color) in order to distinguish them from other parts. In the cross-sectional views of FIGS. 1 and 1 and subsequent sections, hatching such as diagonal lines is omitted from the viewpoint of making some parts 22 easier to see. The region having a higher rubber hardness than the other parts of the thin-walled movable portion 20 also includes both the upper surface (front surface) and the lower surface (back surface). “Other location” means an electron beam non-irradiated region that is not irradiated with an electron beam, which will be described later. Therefore, the other portions are at least the thin-walled movable portion 20 and the base portion 30 that have not been subjected to the hardening treatment without irradiating the electron beam. The pressing portion 10 may be formed of a material different from that of the thin-walled movable portion 20 and the base portion 30, and in that case, the pressing portion 10 is not included in other portions. Instead of the electron beam, vacuum ultraviolet rays having a central wavelength of 172 nm may be used to increase the hardness of the thin-walled movable portion 20.

In this embodiment, the entire region of the thin-walled movable portion 20 is referred to as "at least a part of the portion". Therefore, the thin-walled movable portion 20 has a higher rubber hardness in the range of 2% to 28% than the pressing portion 10 and the base portion 30. Here, the reason why the rubber hardness of some parts 22 is higher than the rubber hardness of other parts in the range of 2% to 28% is as follows. First, when the value is smaller than 2%, the difference between the rubber hardness of some parts 22 and the rubber hardness of other parts is too small, and it is difficult to enhance the feeling of pressing operation. On the other hand, if the value is larger than 28%, the difference between the rubber hardness of some parts 22 and the rubber hardness of other parts is too large, and the durability of the thin-walled movable portion 20 may be lowered. There is. Therefore, the rubber hardness of some parts 22 is made higher in the range of 2% to 28% as compared with other parts. This will be described later with reference to Examples and FIG.

The base portion 30 is connected to the outer circumference of the thin-walled movable portion 20. The base portion 30 is a portion for fixing the push button switch member 1 to a circuit board or the like when the push button switch member 1 is incorporated into the push button switch. In the first embodiment and other embodiments, the top view shape of the base portion 30 is a quadrangle. The base portion 30 may be formed with holes, protrusions, or the like for mounting.

Next, a method of manufacturing the push button switch member according to the first embodiment will be described.

FIG. 2 shows a flowchart of a method for manufacturing a push button switch member according to the first embodiment. FIG. 3 shows a method of manufacturing a push button switch member according to the first embodiment. FIG. 3A is a vertical cross-sectional view after the element body forming step, FIG. 3B is a vertical cross-sectional view of the element body when irradiating an electron beam in the irradiation step, and FIG. 3C is a vertical cross-sectional view. It is a vertical cross-sectional view of a member for a push button switch after an irradiation process.

In the method for manufacturing a push button switch member according to the first embodiment, the pressing portion 10, the thin-walled movable portion 20, and the base portion 30 are formed of a rubber-like elastic body to form a base body 1a for the push button switch member 1. In step S100, at least a part 22 of the thin-walled movable part 20 in the element body 1a is irradiated with an electron beam to make the part 22 harder than the other parts (pressing part 10 and base part 30). The irradiation step S200 and the like are included. The method for manufacturing the push button switch member 1 may further include other steps as long as the forming step S100 and the irradiation step S200 are included.

(1) Formation step S100
As shown in FIG. 3A, the forming step S100 is a step of forming the pressing portion 10, the thin-walled movable portion 20, and the base portion 30 with a rubber-like elastic body to form the element body 1a of the push button switch member 1. is there. However, the pressing portion 10 may not be included.

In the first embodiment, the rubber-like elastic body contains silicone rubber. The forming step S100 is preferably a step of heating a silicone rubber containing a cross-linking agent to form a connecting body of the pressing portion 10, the thin-walled movable portion 20, and the base portion 30. Further, as a modification, the forming step S100 is a step of irradiating a silicone rubber element body 1a composed of a pressing portion 10, a thin-walled movable portion 20 and a base portion 30 and containing no cross-linking agent with an electron beam to form the molding step S100. Is also good. Since the cross-linking agent and the electron beam have the effect of promoting the cross-linking of the silicone rubber, an appropriate molding method can be selected according to the type of the push button switch member 1 and the properties of the raw material. As a method for molding the pressing portion 10, the thin-walled movable portion 20, and the base portion 30, a method using a molding die can be preferably selected.

Further, when the protruding portion 12 is integrated with the pressing portion 10, the protruding portion 12 can also be integrally formed with the pressing portion 10 and the like. On the other hand, when the protruding portion 12 is separate from the pressing portion 10, for example, the protruding portion 12 may be adhered to the pressing portion 10 after molding the element body 1a. The adhesion may be carried out in the forming step, or may be carried out in the step by providing another step. In the first embodiment, the protruding portion 12 is a separate body from the pressing portion 10, and is adhered to the pressing portion 10 in the forming step.

(2) Irradiation step S200
As shown in FIG. 3B, the irradiation step S200 is a step of irradiating a part 22 of the element body 1a with an electron beam e to increase the hardness of the part 22. In the irradiation step S200 of this embodiment, the electron beam e is irradiated from the side (which may be referred to as the upper side or the front side) where the pressing portion 10 protrudes. By adjusting the acceleration voltage of the electron beam e, the depth of a part of the portion 22 (in the first embodiment, the depth reaching the back side of the thin-walled movable portion 20) can be adjusted. The acceleration voltage of the electron beam e can be changed depending on the thickness of the thin-walled movable portion 20 and the depth of a part 22 to be formed, and can be, for example, 200 kV to 500 kV.

In the irradiation step S200, the irradiation dose of the electron beam e is preferably in the range of 25 kGy to 800 kGy. Here, the preferable irradiation dose of the electron beam e is set in the range of 25 kGy to 800 kGy for the following reasons. When the irradiation dose is 25 kGy or more, the progress of cross-linking by the electron beam e becomes sufficient. As a result, the feeling of pressing operation of the push button switch member 1 tends to be sufficiently enhanced. The irradiation dose is more preferably 100 kGy or more. On the other hand, when the irradiation dose is 800 kGy or less, the risk of excessive progress of cross-linking by the electron beam e can be reduced, and the durability of the thin-walled movable portion 20 can be easily maintained. In addition, in order to increase the irradiation dose, the electron beam e may be irradiated to the same position a plurality of times.

(Second Embodiment)
Next, the push button switch member and the manufacturing method thereof according to the second embodiment will be described. The method for manufacturing the push button switch member according to the second embodiment is basically the same as the push button switch member according to the first embodiment, but the irradiation direction of the electron beam in the irradiation step is different. Specifically, in the irradiation step of this embodiment, the electron beam is irradiated from both the front side and the back side of the thin-walled movable portion. Since the push button switch member manufactured by the method for manufacturing the push button switch member according to the second embodiment has the same configuration as the push button switch member according to the first embodiment, its description and illustration will be omitted. ..

FIG. 4 shows a method of manufacturing the push button switch member according to the second embodiment. FIG. 4 corresponds to FIG. 3 (b).

The method for manufacturing the push button switch member according to the second embodiment is different from the case where the irradiation direction of the electron beam e in the irradiation step S200 is different from that of the push button switch member according to the first embodiment. Specifically, in the irradiation step S200, electrons are emitted from both the side surface (upper surface) of the pressing portion 10 and the surface opposite to the pressing portion 10 (lower surface) to the entire thin-walled movable portion 20. Irradiate the line e. By such an irradiation step S200, not only the upper surface of the thin-walled movable portion 20 but also the lower surface can be made harder. Further, not only the front surface (that is, the upper surface) and the back surface (lower surface) of the thin-walled movable portion 20 but also the middle-walled portion can be hardened by short-time irradiation.

(Third Embodiment)
Next, the push button switch member and the manufacturing method thereof according to the third embodiment will be described. In the push button switch member according to the third embodiment, the hardness of only a part of the thin-walled movable portion is higher than the hardness of other parts (the portion of the thin-walled movable portion excluding the part, the pressing portion and the base portion). In that respect, it differs from the first embodiment. Further, in the method for manufacturing a push button switch member according to the third embodiment, an electron beam is irradiated only to a part of a thin-walled movable portion and a surface on the pressing portion side (also referred to as a front surface or an upper surface). It differs from the first embodiment in that it is used. Other than these points, since they are common to the first embodiment, the description and illustration of the common parts will be omitted.

FIG. 5 shows a vertical sectional view (5A) and a plan view (5B) of the push button switch member according to the third embodiment, respectively.

The push button switch member 2 according to this embodiment has hardness in an intermediate region 50 excluding the connecting portion 25 between the thin-walled movable portion 20 and the pressing portion 10 and the connecting portion 26 between the thin-walled movable portion 20 and the base portion 30. It is provided with some higher points 22. In this embodiment, the intermediate region 50 is located at an intermediate position away from the connecting portion 25 and the connecting portion 26 in the thin-walled movable portion 20, but may be any range region as long as the connecting portion 25 and the connecting portion 26 are not included. .. The intermediate region 50 has a higher hardness in the rubber hardness range of 2% to 28% than other portions such as the thin-walled movable portion 20 excluding the intermediate region 50, the pressing portion 10 and the base portion 30. When the pressing portion 10 is made of another material, the intermediate region 50 has a higher hardness than the portion of the thin-walled movable portion 20 and the base portion 30 other than the intermediate region 50. This also applies to other embodiments.

A part of the portion 22 is an upper region from the surface of the thin-walled movable portion 20 on the pressing portion 10 side (also referred to as the upper surface or the front surface) to approximately half of the wall thickness. However, a part of the portion 22 may be a portion formed over the entire area of the thin-walled movable portion 20 in the thickness direction, and the surface of the thin-walled movable portion 20 opposite to the pressing portion 10 (lower surface, back surface). It may be a lower region from (also referred to as) to about half the wall thickness. Further, the part 22 may be a region up to any depth in the entire region in the thickness direction. Further, some of the locations 22 may exist not only at one location but also at two or more locations.

The push button switch member 2 according to this embodiment can be manufactured through the same manufacturing process as the push button switch member 1 according to the first embodiment. However, the irradiation step S200 is different from that of the first embodiment. In the irradiation step S200 of this embodiment, the electron beam e is concentrated in the intermediate region 50, and only that portion is altered so as to have a higher hardness. Further, the irradiation time of the electron beam e is made shorter, or the acceleration voltage of the electron beam e is made lower, so that the irradiation dose of the electron beam e is made smaller than that of the first embodiment. As a result, the hardness of the thin movable portion 20 is increased only to about the upper half of the wall thickness. The irradiation direction of the electron beam e (direction from top to bottom in the figure) is the same as that of the first embodiment.

In this way, since the push button switch member 2 has a high hardness only in the intermediate region 50 excluding the connecting portions 25 and 26, for example, the thin-walled movable portion 20 is removed from the connecting portions 25 and 26 with long-term use. It is less likely that the push button switch member 2 will be torn and the push button switch member 2 cannot be used. That is, increasing the hardness of only the intermediate region 50 contributes to prolonging the life cycle in addition to enhancing the pressing operation feeling of the push button switch member 2. Further, since the push button switch member 2 only forms a part of the portion 22 from the front surface of the intermediate region 50 to the intermediate position of the wall thickness, the push button switch component (metal) is formed on the back side of the thin movable portion 20. It is possible to reduce the possibility that the thin-walled movable portion 20 is scratched or torn from the contact (dome, electrode, etc.).

(Fourth Embodiment)
Next, the push button switch member and the manufacturing method thereof according to the fourth embodiment will be described. The push button switch member according to the fourth embodiment has a structure in which the push button switch member according to the first embodiment and the push button switch member according to the third embodiment are connected in the horizontal direction. Since the push button switch member according to the fourth embodiment is common to that of the first embodiment except for the above points, the description and illustration of the common parts will be omitted.

FIG. 6 shows a vertical sectional view (6A) and a plan view (6B) of the push button switch member according to the fourth embodiment, respectively.

As shown in FIG. 6, the push button switch member 3 according to the fourth embodiment includes a first switch component 3a having a pressing portion 10a, a protruding portion 12a, and a thin movable portion 20a, and a pressing portion 10b and a protruding portion 12b. It has a structure in which the second switch component 3b provided with the thin-walled movable portion 20b and the second switch component 3b are connected in the horizontal direction in a form sharing the base portion 30.

The thin-walled movable portion 20a of the first switch component 3a includes a part portion 22a in which the entire region thereof is made harder than the other portions (pressing portion 10a and base portion 30). On the other hand, the thin-walled movable portion 20b of the second switch component 3b has an intermediate region 50b made harder than other portions (the region other than the intermediate region 50b of the thin-walled movable portion 20b, the pressing portion 10b and the base portion 30). A part of the portion 22b is provided. As described above, the push button switch member 3 includes some portions 22a and 22b whose length direction and thickness direction are different from each other. In the present application, such a form is referred to as "a form in which the pattern of some parts is different". That is, "a form in which the pattern of some parts is different" means that when one thin-walled movable portion 20a and another thin-walled movable part 20b are compared, some of the parts 22a and 22b formed there. It means that the positions or sizes are not the same, but different forms.

The push button switch member 3 has basically the same manufacturing method as the push button switch member manufacturing method according to the first embodiment, that is, the element body (pressing portion) corresponding to the push button switch member 3 in the forming step S100. It can be manufactured by a method of forming 10a, 10b, a molded body including thin-walled movable portions 20a, 20b, and a base portion 30), and forming some portions 22a, 22b in the subsequent irradiation step S200. In order to form some of the locations 22a and 22b having different morphologies from each other, it is preferable to change the region to be irradiated with the electron beam e and the irradiation dose at the time of formation.

(Fifth Embodiment)
Next, the push button switch member and the manufacturing method thereof according to the fifth embodiment will be described. The push button switch member according to the fifth embodiment is a third switch having a second switch component in which only the intermediate region is hardened and a thin-walled movable portion in which none of the thin-walled movable parts is hardened. It is common to the push button switch member according to the fourth embodiment except that the parts are replaced. Therefore, the description and illustration of the common part will be omitted.

FIG. 7 shows a vertical sectional view (7A) and a plan view (7B) of the push button switch member according to the fifth embodiment, respectively.

As shown in FIG. 7, the push button switch member 4 according to the fifth embodiment includes a first switch component 4a having a pressing portion 10a, a protruding portion 12a, and a thin movable portion 20a, and a pressing portion 10c and a protruding portion 12c. It has a structure in which the third switch component 4c provided with the thin-walled movable portion 20c is connected in the horizontal direction in a form sharing the base portion 30.

The push button switch member 4 includes a part of the portion 22a only in the thin-walled movable portion 20a of the first switch component 4a. The part of the portion 22a is a portion where the entire region of the thin-walled movable portion 20a is harder than the other portions (pressing portion 10a and base portion 30). On the other hand, the thin-walled movable portion 20c of the third switch component 4c is not hardened at all and does not have a portion corresponding to a part of the portion 22a. As described above, the push button switch member 4 includes a part 22a only in a part of the switch parts (the first switch part 4a in this embodiment), and the other switch parts (the third in this embodiment). A form in which a part of the switch component 4c) is not provided is also referred to as "a form in which the pattern of some parts is different" in the present application. That is, "a form in which the pattern of some parts is different" means that when one thin-walled movable portion 20a is compared with another thin-walled movable part 20c, the position or size of some parts formed therein is compared. It means that they are not the same, but have different forms.

The push button switch member 4 has basically the same manufacturing method as the push button switch member manufacturing method according to the first embodiment, that is, the element body (pressing portion) corresponding to the push button switch member 4 in the forming step S100. 10a, 10c, a molded body including the thin-walled movable portions 20a, 20c and the base portion 30), and in the subsequent irradiation step S200, a part of the portion 22a is formed only on one of the thin-walled movable portions 20a. can do.

(Other embodiments)
Although the preferred embodiments of the present invention have been described above, the push button switch member according to the present invention can be variously modified and implemented as described below without being restricted by the respective embodiments.

Pressing portions 10, 10a, 10b, 10c (referred to as pressing portion 10 and the like), protruding portions 12, 12a, 12b and 12c (referred to as pressing portion 12 and the like), thin-walled movable portions 20, 20a, 20b and 20c in each of the above-described embodiments. Each shape of the base portion 30 (referred to as a thin-walled movable portion 20 or the like) is an example, and each shape can be various according to the application or the like. Further, the plan-view shapes of the pressing portion 10 and the like, the protruding portion 12 and the like, and the thin-walled movable portion 20 and the like do not have to be the same. The plan view shape of the outer edge portion (connecting portions 26, 26b connected to the base portion 30) of the thin-walled movable portion 20 or the like may be a quadrangle. Furthermore, the cross-sectional visual shapes of the pressing portion 10 and the like, the protruding portion 12 and the like, the thin-walled movable portion 20 and the like do not have to be the same. On the contrary, each plan view shape or each cross-sectional view shape of the pressing portion 10, the protruding portion 12, the thin-walled movable portion, etc. may be the same circle or the same quadrangle.

Further, some of the locations 22, 22a and 22b are examples, and can be formed at various positions or sizes according to the intended use and the like. Hereinafter, modification examples of some parts will be described.

FIG. 8 shows a plan view (8A, 8B) of the push button switch member according to the modified example.

In the push button switch member 5 according to the first modification shown in FIG. 8 (8A), the upper region 51 from a position substantially intermediate in the length of the thin-walled movable portion 20 to the connecting portion 25 connected to the pressing portion 10 is another portion. It is a part 22 having a higher hardness than (a region other than the upper region 51 of the thin-walled movable portion 20, a pressing portion 10 and a base portion 30). On the other hand, in the push button switch member 6 according to the second modification shown in FIG. 8 (8B), the lower region 52 from the position substantially intermediate in the length of the thin-walled movable portion 20 to the connecting portion 26 connecting with the base portion 30 is other. (Area other than the lower region 52 of the thin-walled movable portion 20, the pressing portion 10 and the base portion 30), the hardness is higher than that of the portion 22. As described above, the part 22 may be formed in the intermediate region 50 of the thin-walled movable portion 20 as in the third embodiment, or may be formed in the upper region 51 or the lower region 52. Further, when increasing the hardness of the upper region 51 or the lower region 52, a) the hardness may be increased in all directions of the wall thickness, and b) the surface (upper surface or surface) on the pressing portion 10 side may be increased in hardness. It is not necessary to increase the hardness of the surface (lower surface or back surface) on the opposite side of the surface (lower surface or back surface), or c) the surface on the opposite side of b) is not required to be increased in hardness to increase the hardness of the surface on the pressing portion 10 side. good.

Further, when forming a part 22 of the above a), the electron beam e can be irradiated from the pressing portion 10 side and / or the opposite side of the thin-walled movable portion 20. On the other hand, when forming a part 22 of the above b) and the above c), the electron beam e can be irradiated from the pressing portion 10 side and the opposite side of the thin-walled movable portion 20, respectively.

In the above-described fourth embodiment, the number of each of the pressing portions 10a and 10b and the thin-walled movable portions 20a and 20b is only two, but the number may be three or more. This also applies to the fifth embodiment. Further, in the fourth embodiment and the fifth embodiment, the push button switch members 3 and 4 sharing the base portion 30 are illustrated, but the base portion 30 is provided for the first switch component 3a and the second switch component 3b, respectively. Or the base portion 30 may be provided on the first switch component 4a and the third switch component 4c, respectively.

In each of the above-described embodiments, the rubber-like elastic body contains silicone rubber, but it does not necessarily have to contain silicone rubber. The rubber-like elastic body may be a material that can increase the rubber hardness by irradiation with an electron beam e and that is elastically deformable and suitable for switch operation.

Further, the components of the push button switch members 1 to 6 (referred to as push button switch members 1 and the like) in each embodiment and each modification can be arbitrarily combined with each other unless they cannot be combined. For example, the push button switch member 5 (see FIG. 8 (8A)) according to the first modification is the first switch component 3a or the second switch component 3a or the second switch member 3 (see FIG. 6) of the push button switch member 3 according to the fourth embodiment. It may be substituted for the switch component 3b. Similarly, the push button switch member 6 (see FIG. 8 (8B)) according to the second modification is the first switch component 4a or the first switch component 4a or the push button switch member 4 (see FIG. 7) according to the fifth embodiment. 3 It may be substituted for the switch component 4c.

Next, examples of the present invention will be described with reference to the drawings. However, the present invention is not limited to the following examples.

(Examples 1 to 8 and Comparative Examples 1 to 8)
(1) Form of Element Body for Push Button Switch Member FIG. 9 shows a vertical cross-sectional view of the element body for the push button switch member used in each Example and each Comparative Example.

The element body 1b was made of silicone rubber. Here, the diameter a of the cylindrical pressing portion 10 constituting the element body 1b is 3.5 mm. The height b from the top surface of the pressing portion 10 of the body 1b to the bottom surface of the base portion 30 is 2.6 mm. The distance c from the bottom surface of the protruding portion 12 to the bottom surface of the base portion 30 is 0.8 mm. The thickness d of the base portion 30 is 0.7 mm. The diameter e of the lower opening surface of the thin-walled movable portion 20 is 5.2 mm. The wall thickness of the thin movable portion 20 is 0.23 mm. In order to confirm the effect of the irradiation dose of the electron beam, a plurality of element bodies 1b were formed. Although not shown, a PET film having a thickness of 100 μm was placed under the base portion 30 so that the base portion 30 would not expand excessively when the pressing portion 10 was pressed.

(2) Method for Manufacturing Element Body of Push Button Switch Member First, the element body 1b shown in FIG. 9 was formed by a method corresponding to the forming step S100 in the first embodiment. KE-951-U (product number) manufactured by Shin-Etsu Chemical Industry Co., Ltd. as the first curable silicone rubber composition for forming the element body 1b and KE manufactured by the same company as the second curable silicone rubber composition. -78 VBS (product number) is mixed at a weight ratio of 90:10, and with respect to 100 parts by mass of this mixture, 2 parts of C-8 (product number) manufactured by the same company as a vulcanizing agent and KE manufactured by the same company as the first pigment. -COLOR-W2 (product number) 0.5 parts by mass and 0.005 parts by mass of KE-COLOR-MB (product number) manufactured by the same company as the second pigment were added. The element body 1b was molded using a mold. After the molding, the protruding portion 12 was adhered to the lower surface of the pressing portion 10 to complete the element body 1b.

(3) Method for increasing hardness of thin-walled movable portion The thin-walled movable portion 20 of the element body 1b was irradiated with an electron beam under various conditions. An electron beam irradiation device (model: EC250 / 30/90LS) manufactured by Iwasaki Electric Co., Ltd. was used for electron beam irradiation. The electron beam was irradiated from the front side of the element body 1b, assuming that the side on which the pressing portion 10 protrudes is the front side. The acceleration voltage of the electron beam was set to 250 kV so that the entire thin-walled movable portion 20 could reach a part of the portion 22 and the electron beam could reach from the front surface to the back surface of the thin-walled movable portion 20. The processing speed of electron beam irradiation was set to 5 m / min. Here, the processing speed refers to the speed at which the stage on which the push button switch member is placed passes through the electron beam irradiation position. The irradiation dose of the electron beam can be adjusted by the beam current of the electron beam, the processing speed, and the number of passages of the electron beam irradiation position.

The irradiation dose of the electron beam was changed in 16 steps within the range of 0 to 3000 kGy to complete the push button switch member. Comparative Example 1 when no electron beam was irradiated (irradiation dose: 0 kGy), Example 1 when the irradiation dose was 25 kGy, Example 2 when the irradiation dose was 50 kGy, and the case where the irradiation dose was 100 kGy. Example 3, Example 4 when irradiated with an irradiation dose of 200 kGy, Example 5 when irradiated with an irradiation dose of 300 kGy, Example 6 when irradiated with an irradiation dose of 600 kGy, and a case where an irradiation dose of 700 kGy was irradiated. Example 7, the case of irradiating an irradiation dose of 800 kGy is Example 8, the case of irradiating an irradiation dose of 900 kGy is Comparative Example 2, the case of irradiating an irradiation dose of 1000 kGy is Comparative Example 3, and the case of irradiating an irradiation dose of 1100 kGy is Comparative Example 4. Comparative Example 5 was given an irradiation dose of 1200 kGy, Comparative Example 6 was given an irradiation dose of 1500 kGy, Comparative Example 7 was given an irradiation dose of 2000 kGy, and Comparative Example 8 was given an irradiation dose of 3000 kGy. ..

(4) Evaluation of Elementary Body For a plurality of elemental bodies 1b produced under the above conditions, the rubber hardness of each thin-walled movable portion 20 and the pressing portion 10 are pressed to completely buckle and deform the thin-walled movable portion 20. The maximum load (= peak load) required for this was measured. A hardness measuring instrument (model: MD-1capa) manufactured by Polymer Meter Co., Ltd. was used for measuring the rubber hardness. Rubber hardness refers to rubber hardness measured by a Type A durometer conforming to JIS K 6253. The rubber hardness was measured at two points for each sample, and the average value was taken as the rubber hardness of the sample. An automatic load tester (model: MAX-1KN-S-1) manufactured by Nippon Measurement System Co., Ltd. was used to measure the peak load. The rubber hardness and the peak load measured in the above manner correspond to the numbers of the "before irradiation" items of the "rubber hardness" and the "peak load" in FIG. 10 shown later.

(5) Evaluation of push button switch members The rubber hardness and peak load of the thin-walled movable portion 20 were measured for 16 types of push button switch members manufactured by changing the irradiation dose. The measured rubber hardness and peak load correspond to the numbers in the "after irradiation" items of "rubber hardness" and "peak load" in FIG. 10 shown later. Further, with respect to the above 16 types of push button switch members, the return load, which is the load when the thin-walled movable portion 20 buckled and deformed after pressing starts to return, was also measured. For the measurement of the return load, the same device as the measurement of the peak load was used. In addition, a keystroke test was conducted on the push button switch member. The load in the keystroke test was 580 g, and the keystrokes were performed 150,000 times at a keystroke speed of 3 times / second. After that, it was confirmed whether or not the thin-walled movable portion 20 was torn.

FIG. 10 shows the evaluation results of each Example and each Comparative Example.

In Comparative Examples 7 and 8, since the thin-walled movable portion 20 was torn immediately after the peak load was measured, the peak load could not be measured and the keystroke test could not be performed. In the item of "presence or absence of tear" in FIG. 10, "○" indicates that the thin-walled movable portion 20 was not torn after the keystroke test, and "x" indicates that the thin-walled movable portion 20 was not torn after the keystroke test. Is shown. Further, in the item of "return residual rate" in FIG. 10, "○" indicates that the return residual rate was 55% or more after the keystroke test, and "Δ" indicates that the return residual rate was less than 55% after the keystroke test. “X” indicates that the thin-walled movable portion 20 was torn after the keystroke test, and the return residual rate could not be measured. The return residual rate is a numerical value indicating what percentage of the return load after the keystroke test is the return load before the keystroke test. The decrease in the returning force means that the force for returning the buckled push button switch to the non-buckled state by pushing is decreased. In this experiment, the return residual rate of 55% is a critical value at which the push button switch in the buckled state returns to the state before buckling.

As a result of various evaluations, as shown in FIG. 10, it is possible to increase the rubber hardness of some parts by irradiating the thin-walled movable portion 20 with an electron beam, and depending on the change in the peak load. It was confirmed that the feeling of pressing operation can be changed. Further, by setting the degree of making the rubber hardness of some parts higher than the rubber hardness of other parts (the rate of change of rubber hardness) to 2% or more, the peak hardness can be increased and the feeling of pressing operation can be changed. It was confirmed that it was possible. On the other hand, by setting the degree of making the rubber hardness of some parts higher than the rubber hardness of other parts (the rate of change of rubber hardness) to 28% or less, it is possible to suppress the deterioration of the durability of the thin-walled movable portion 20. It was also confirmed that it was possible. Further, in the case of Examples 1 to 8, in order to make the rubber hardness of some parts higher than the rubber hardness of other parts in the range of 2% to 28%, the irradiation dose of the electron beam is 25 kGy to 800 kGy. It was confirmed that it is preferable to keep it within the range. Further, by setting the irradiation dose of the electron beam to 100 kGy to 800 kGy, a good recovery residual rate could be obtained.

The push button switch member according to the present invention is used in various devices having a press-type key, such as a mobile communication device, a personal computer, a camera, an automobile, an in-vehicle electronic device, a home audio device, and a home electric appliance. It can be used to configure a push button switch.

1,2,3,4,5,6 ... Push button switch member, 1a, 1b ... Element body, 10,10a, 10b, 10c ... Pressing part, 20, 20a, 20b, 20c ... -Thin-walled movable parts, 22, 22a, 22b ... some parts, 25, 25b ... connecting parts, 26, 26b ... connecting parts, 30 ... base parts, 50, 50b ... intermediate Region, e ... electron beam.

Claims (6)

Pressing part and
A thin movable part connected to the outer circumference of the pressing part and
The base portion connected to the outer circumference of the thin-walled movable portion and
With
The pressing portion projects to one side with respect to the base portion.
The pressing portion, the thin-walled movable portion, and the base portion are made of the same type of rubber-like elastic body.
Wherein at least the rubber hardness of the partial portion of the thin movable portion high rather in the range of 2% to 28% than the rubber hardness of the other portions,
The part of the thin-walled movable portion having a higher rubber hardness is an intermediate region excluding the connecting portion between the thin-walled movable portion and the pressing portion and the connecting portion between the thin-walled movable portion and the base portion. , And at least a push button switch member including a surface on the side of the pressing portion. The push button switch member according to claim 1, wherein a part of the portion is an upper region in the intermediate region from the surface on the pressing portion side to half the wall thickness. The push button switch member according to claim 1 or 2 , wherein the rubber-like elastic body contains silicone rubber. It includes a pressing portion, a thin-walled movable portion connected to the outer periphery of the pressing portion, and a base portion connected to the outer periphery of the thin-walled movable portion, and the pressing portion projects to one side with reference to the base portion. The pressing portion, the thin-walled movable portion, and the base portion are made of the same type of rubber-like elastic body, and the rubber hardness of at least a part of the thin-walled movable portion is 2% to the rubber hardness of other parts. rather high 28% range, more high the part locations of the rubber hardness at the thin movable part is connected with the thin movable portion and the connecting portion between the pressing portion, and the thin movable portion and the base portion A method for manufacturing a push button switch member, which is an intermediate region excluding a portion and includes at least a surface on the side of the pressing portion.
A forming step of forming the pressing portion, the thin-walled movable portion, and the base portion with the rubber-like elastic body to form a base body of the push button switch member.
An irradiation step of the higher hardness than the thin movable portion of at least the said portion and irradiating an electron beam to a part of the location points of the other locations in the body,
A method for manufacturing a member for a push button switch including. The method for manufacturing a push button switch member according to claim 4, wherein the partial portion is an upper region from the surface on the pressing portion side to half the wall thickness in the intermediate region. The method for manufacturing a push button switch member according to claim 4 or 5 , wherein in the irradiation step, the irradiation dose of the electron beam is in the range of 25 kGy to 800 kGy.

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