JPS62259314A - Covering member for keyboard - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a cover member for a keyboard, particularly a cover for a keyboard which is useful for manual use of keys in which a large number of push button members are individually attached to one substrate. It is related to members.

(Prior Art) Conventionally, a keyboard cover member 9 carrying movable contacts arranged opposite to an array pattern of fixed contacts provided on a printed circuit board has a push button part 7 and a push button base part 8 connected and integrated. However, this type of keyboard cover member 9 as shown in FIG. After a movable contact made of vulcanized conductive rubber is buried in a cavity corresponding to the arrangement pattern of fixed contacts (not shown), unvulcanized insulating rubber is placed on top of the movable contact and heated. Because the push button parts 7 and the push button base part 8 are connected and integrated by pressing, it is possible to create a keyboard cover member 9 as shown in FIG. In order to obtain this, a new mold must be prepared, and when creating this mold, it is necessary to take into account the expansion and contraction of the molded product that will affect the entire keyboard cover member after molding, as well as the expansion and contraction during use. A new trial-and-error mold design was carried out.

Not only does R1 construction require inspection, but it is also 20
A large keyboard cover member mold of about 50 Cfn requires a geometrically higher total mold cost than a small one (about 5 XIOσ), and a large press machine must be prepared. There was a disadvantage.

Furthermore, in order to manufacture a keyboard cover member with push button parts of different hues, which has been in demand recently, it is necessary to simultaneously place unvulcanized insulating rubber of the required hue in the cavity and then heat and pressurize it. Therefore, the hues tend to mix at the boundary, so the product does not have the intended hue boundary, and the yield is extremely poor, making it unsuitable for high-mix, low-volume production, resulting in high costs. .

(Structure of the Invention) The present invention relates to a cover member for a keyboard that solves the above-mentioned disadvantages.The present invention relates to a cover member for a keyboard that solves the above-mentioned disadvantages. It is characterized by being fixed with.

That is, as a result of various studies conducted by the present inventors on an inexpensive manufacturing method for a keyboard cover member that can accommodate high-mix, low-volume production, the inventors of the present invention have developed a method for manufacturing a keyboard cover member in which a large number of push button parts are connected to and integrated with a push button base member. Instead of molding them in a mold, prepare a large number of push button members, place them on a board that has been punched in a desired pattern, apply adhesive to the second If it is fixed to the board using the adhesive force of the adhesive, there will be no need for molds that have been manufactured each time for each array pattern of array contacts, and the associated costs will be eliminated. If the component is fixed to the board using an adhesive, this installation cost can be reduced, so the desired keyboard cover member can be obtained at a low cost, and with this method, it is possible to make holes in the board by drilling. The present invention was completed based on the discovery that a cover member for a keyboard having an arbitrary pattern can be obtained by this method, and thus it can be readily adapted to high-mix, low-volume production.

The shape, material, and color tone of the push button member constituting the keyboard cover member of the present invention may be those used for the push button portion of a known keyboard cover member of this type, and therefore, it has a sliding portion. Elastella is an inverted bowl-shaped elastic rubber rod.

The elasticity of the push button is made of a metal plate, and push buttons with different sizes, strokes, loads, appearances, etc. can be appropriately selected and used in combination. This elastic push button member is made of natural rubber or diene-based synthetic rubber such as polybutadiene, polyisoprene, SBR, neoprene, etc.
It may be made of synthetic rubber such as ethylene-propylene, urethane, polyester, or silicone, or a combination thereof, which is heat resistant.

It is best to use silicone rubber, which has excellent weather resistance and electrical insulation properties.On the other hand, if a metal plate is used, stainless steel, phosphor bronze, beryllium copper, or those plated with gold or silver may be used. The plate-like body may be pressed into an inverted bowl shape and given elasticity using a disc spring. Note that it is optional to apply a suitable primer to the bonding portion with the silicone rubber in order to improve the adhesion with the silicone rubber, which will be described later.

Further, this push button member may be made entirely insulating or entirely conductive, but usually the contact part is conductive and the dome part is insulating.
These are compression molding and injection molding.

It may be made by counting a large number of pieces using a known method such as transfer molding.

On the other hand, the substrate constituting the keyboard cover member of the present invention is said to have punched through holes for arranging the above-mentioned push button members, and this is made of polyester, polycarbonate, polyacrylate, polyarylate, polyimide,
It may be made of plastic such as silicone rubber, rubber, metal plate, metal foil, or a laminated combination of these as appropriate.The size of this board can be determined according to the intended use of the keyboard. However, if the thickness is less than 10u, it is too thin and transportation becomes inconvenient;
If the thickness is more than 00 μm, the material cost will be high and the punching process will be difficult, so it is desirable to have a thickness in the range of 10 to 2,000 tm.

This preferable range is 75 to 300μ. This board hole punching process can be done by punching, laser processing, biku blade processing, etc., but the number of holes is limited.

The placement depends on the intended use of the keyboard cover member.

Any pattern determined by usage conditions or molding shrinkage after assembly may be used, and the hole size 15 is determined by the first hole size.
When placing it from above on the board 3 as shown in the figure, the dome inner diameter is 12
When arranging from below to the movable contact 11 on the board 3 as shown in Fig. 2, there is no need to worry about the occurrence of hangnails in the hole part of the board during punching or the possibility of contact with the dome part of the push button member 1 when pressing. 0.05~5.
It is preferable to set the outer diameter 14 of the leg 0wa, preferably 0.2 to 2.0 m larger than the hole diameter 15, in order to secure the bonding area between the push button member leg 2 and the substrate 3. 0
It is preferable to take a larger value, preferably 2.0 to 4.0 m. Further, the outer shape of the keyboard cover member of the present invention may be cut with an outer shape punching blade or laser cut during or after punching.

Although this base material is usually electrically insulating, it may be conductive or semiconductive to prevent static electricity, prevent static electricity damage, and shield electromagnetic waves; In order to do this, it can be made of plastic or rubber kneaded with conductive carbon black, carbon fiber, metal powder, metal fiber, etc., or the base material itself can be made of a metal plate, but this can be made of an insulating material. It may be made of aluminum coated with conductive paint, vacuum-deposited or plated with metal, or laminated with conductive material.

The keyboard cover member of the present invention is made by arranging the push button members described above in the holes of a substrate in which through holes are arranged by the above-described punching process, and fixing them with an adhesive.

The keyboard cover member of the present invention is made by arranging the single push button switch member described above in the hole of the base material which has been subjected to the punching process described above, and fixing them with an adhesive. Rubbers such as natural rubber, 5BR1 recycled rubber, polyisobutylene, and block rubber, monomers such as acrylic acid, methacrylic acid, acrylamide, vinyl acetate, and styrene, mainly consisting of acrylic esters having 1 to 1.2 carbon atoms. These include acrylic resins copolymerized with silicone rubber and silicone resins obtained by the condensation reaction of a hydrolyzate of silicone rubber and organochlorosilane. Any type may be used, and when classified by state, they are organic solvent type, emulsion type, hot melt type, and aqueous solution type, but in reality, any type may be selected depending on the materials of the push button switch member and the base material. This is also a hot melt type processed into a sheet, with the same type of base material,
Alternatively, it may be a multilayer structure made of a double-sided tape type in which different materials are laminated on one or both sides. The adhesive may be applied to the entire surface of the base material by a casting method, a topping method, etc., and if necessary, a cover film may be laminated and holes may be punched.

In addition, in the keyboard cover member of the present invention, the push button member and the punched board are fixed by applying adhesive, so there is no positional shift during key presses, and from a functional point of view, it is better than conventional keyboard cover members. A cover member that is no different from the known continuous and integrated keyboard cover member is provided, but the push button member and the substrate are coated with a suitable primer such as a silane coupling agent or a titanate coupling agent in advance. You can also optionally process it.

Regarding the application of this adhesive to the push button member and the board, it is possible to apply it to the entire board surface or only to the periphery of the hole or to the leg part of the push button member on the board side using a casting method, topping method, printing method, etc. before or after punching the hole. However, if necessary, this board may be provided with a cover film layer 10. to prevent dirt, dust, etc. from adhering to the adhesive exposed area after fixing the push button member. (For example, polyester film, polypropylene film, polyethylene film, high quality paper, kraft paper, release paper, powder, bead fiber, adhesive, etc., appropriately selected) may be provided to remove tackiness. The application of this adhesive is usually in the order of 0.005 to 20, preferably 0.
．． The length should preferably be about 0.4 to 0.3 m, and adhesive fixing can be performed efficiently.

Next, the keyboard cover member of the present invention will be explained with reference to the accompanying drawings. 1 to 4 are longitudinal cross-sectional views of essential parts of the keyboard cover member of the present invention. In FIG. In FIG. 2, the leg part 2 of the push button member 1 is adhesively fixed under the peripheral part of the through hole 4 of the substrate 3 with adhesive 5. In the figure, the leg part 2 of the push button member 1 is adhesively fixed to the side wall of the through hole part 4 of the board 3 at 5, and in FIG. The one shown is one that is fitted onto a protrusion 6 provided in the vicinity of 4 and fixed with adhesive 5, but the one in Fig. 2 has no fear of dust accumulation due to the step in the adhesive fixed part. Since there is no stroke change that reduces the thickness of the substrate and the adhesive, it is advantageous that the shape of the push button part used for the push button part of this type of keyboard cover member can be reused in its entirety.

The keyboard cover member of the present invention obtained in this way is different from the conventional keyboard cover member in that the push button base portion and the push button are connected and integrated to form a keyboard cover member on each side. Whereas it was necessary to use a mold designed for the cover member, a specific single or multiple standard push button members are used, and the board can also be punched out arbitrarily to match the arrangement pattern of the fixed contacts. This gives the advantage of being able to easily and inexpensively obtain a keyboard cover member with any pattern, which also enables high-mix, low-volume production and shortens delivery times. It also has the industrial advantage of improving production efficiency.

Next, examples of the present invention will be given.

Reference Example 1 (Production of push button member) Add 3 parts of acetylene black powder to 70 parts of silicone rubber compound KE742U (trade name manufactured by Shin-Etsu Chemical Co., Ltd.)
A conductive rubber containing 0 part of dicumyl peroxide and 0.5 part of dicumyl peroxide is molded at 50 kg/al at 170°C to make a conductive contact, which is then inserted into a predetermined movable contact of a mold for molding a push button member. After placing the mold in the appropriate position, add 100 parts of silicone rubber compound KE951U (part name manufactured by Shin-Etsu Chemical Co., Ltd.) to 1.5 parts of dicumyl peroxide.
and an insulating rubber compound containing 0.5 parts of colorant (white) and molded at 50 kg/aJ and 170°C to obtain an outer diameter in which the conductive contact and the insulating rubber are integrally molded. 9.5 cabinets, inner diameter 5-.

Dome inner diameter 8.7m, height 3.3m, thickness 0.8m
48 push button members for the cabinet are surrounded by thin parting lines with parallel spacing of 13 m in vertical rows and 15 cm in horizontal rows.A large number of 10 push button member precursors are produced. It was divided into 15 m rectangles using thin dividing lines.

Reference Example 2 100 parts of ethylene propylene rubber EPDM501A (trade name manufactured by Sumima Kagaku Kogyo ■), 40 parts of calcium carbonate, 3 parts of dicumyl peroxide, 1 part of vulcanization aid, 0.5 part of colorant (red) and paraffin. Charge the insulating rubber compound containing 40 parts of softener into the mold, 50 kg/c
nf, 170'C (7) conditions and produced a large number of 480 push button members in the same manner as in Reference Example 1, which were divided into rectangles each measuring 13 mm in length and 15 mm in width.

Reference Example 3 The same material as Reference Example 1 was used except that the colorant was black, and the conductive contact and insulating rubber were integrally molded under the same molding conditions. Inner diameter 10.0++
a. A large number of 260 push button members (26 XIO pieces) each with a dome inner diameter of 13.4 m, a height of 6-1, and a thickness of 0.8 m were produced, and each was divided into circles with a diameter of 18.4 mm. .

Reference Example 4 Same as Reference Example 3 except that the coloring agent was changed to blue, but the outside diameter was 8.0 m, the inner diameter was 5.0 m, and the dome inner diameter was 7.411I1.
1. Push button member 77 with a height of 3.0mm and a thickness of 0.7+nm
A large number of 0 pieces (77 pieces x 10 pieces) are produced, and these are made into 1 piece.
Each piece was divided into rectangles with a length of 10 mm and a width of 12 mm.

Example 1 A silicone pressure-sensitive adhesive KR-101-10 [part name manufactured by Shin-Etsu Chemical Co., Ltd.] was cast to a thickness of 0.10 m on a 100 x 100 x 0.15 m polyester sheet using a casting method.
After applying the coating to a polypropylene film, a polypropylene film is laminated, and then a punch is used to punch 16 holes with a diameter of 11.5 nm at a pitch of 15.5 an, in a pattern of 4 vertically and 4 horizontally.
After performing individual punching, the polypropylene film was peeled off.

Next, the holes were made by inserting the legs of the 16 push button switch members obtained in Reference Example 1 into the holes of the processed polyester sheet, and adhering them to the polyester sheet with adhesive.
When I made the keyboard shown in Figure 2, the pushbutton switches passed a test of 1 million keystrokes.

Example 2 Acrylic pressure sensitive adhesive DA-672 (trade name manufactured by Nogawa Chemical ■) was applied to a 100 x 100 x 0.15 + m polyester sheet to a thickness of 0.07 mm by a casting method, and then a polypropylene film was laminated.
Next, 16 holes each having a diameter of 11.5 mm were punched out using a punch in a pattern of 4 holes vertically and 4 holes horizontally at a pitch of 15.5 mm, and then the polypropylene film was peeled off.

Next, the legs of the 16 push button switch members obtained in Reference Example 2 were inserted into the holes of the processed polyester sheet, and the legs were adhered to the polyester sheet adhesive, as shown in Fig. 2. When he created a new keyboard, the pushbutton switches passed a test of 1 million keystrokes.

Example 3 The acrylic side of the pressure-sensitive double-sided adhesive tape 5302 (trade name of Nitto Electric Industry Co., Ltd.) consisting of three layers of acrylic, intermediate base material, and silicone was laminated on a 120 x 350 Using a blade, 60 holes with an outer size of 1100 x 320 nm and a diameter of 16.0 mm were punched out in a pattern of 4 vertically and 15 horizontally with a pitch of 19.05III11.

Next, the holes were made by inserting and arranging 60 push button switch members obtained in Reference Example 3 into the holes of the processed polyester sheet and adhering them to the polyester sheet to make the keyboard shown in Figure 2. , this pushbutton switch is 100
Passed the keystroke test 10,000 times.

Example 4 Silicone adhesive KR-101-10 [mentioned above] was applied to a 120X80XO, 1m polycarbonate sheet by a casting method to a thickness of 0.08rItm, and then a polypropylene film was laminated thereon, using a punch. After punching 20 holes with a diameter of 9.0 aa in a pattern of 4 vertically and 5 horizontally at a pitch of 15.0 m, the propylene film was peeled off.

Next, to make this hole, insert and arrange 20 push button switch members obtained in Reference Example 4 into the holes of the processed polycarbonate sheet, adhere them to the polycarbonate sheet, and laminate a cover film on the exposed adhesive part. When I made a keyboard using this method, the push button switch passed a test of 1 million keystrokes.

[Brief explanation of drawings]

FIG. 1 shows a longitudinal sectional view of a main part of a keyboard cover member of the present invention, and FIGS. 2 to 4 show longitudinal sectional views of main parts of a keyboard cover member of another embodiment of the invention. 5 and 6 are perspective views of a conventionally known keyboard cover member. 1...Push button member. 2... Leg portion, 3... Substrate, 4... Hole portion, 5... Adhesive 5, 6... Protrusion, 7... Push button portion. 8...Push button base portion, 9...Keyboard cover member, 10...Cover film layer, 11...Movable contact outer diameter. 12...Dome inner diameter. 13... Outer diameter, 14... Leg outer diameter, 15... Hole outer diameter. Procedural amendment dated March 20, 1988 1. Indication of the case Patent Application No. 102286 of 1988 2. Name of the invention Keyboard cover member 3. Person making the amendment Relationship to the case Patent applicant name Shin-Etsu Polymer Co., Ltd. 4. Agent 7, contents of amendment l) Amend "Movable contact 11" in line 2 of page 7 of the specification to "Movable contact (blacked part in the figure)". 2) Change "During keystroke durability" on page 7, line 2 of the specification to "At keystroke time"
and correct it. 3) "5 on the periphery" on page 11 of the specification, lines 4 to 5
is corrected to ``apply adhesive 5, for example, room temperature curable silicone rubber KEI, 800A, B, C [name of part manufactured by Shin-Etsu Chemical Co., Ltd.] on the peripheral edge.'' 4) In page 11, line 8 of the specification, "5 on the side wall" is corrected to "5 on the side wall with adhesive." 5) Replace Figure 1 with the one on the separate sheet. that's all

Claims (1)

[Claims] 1. A cover member for a keyboard, characterized in that a push button member is fixed with an adhesive to the periphery of a substrate in which through holes are arranged in accordance with a push button arrangement pattern.