JP2001187968A - Gasket for electric and electronic apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gasket for an electric and electronic apparatus improved in rigidity, shape stability and assembling property so that the hardness is easily adjustable and capable of reducing the cost for product or the like. SOLUTION: A thin frame-like base material 4 is nipped by opposed ribs 3 which are circumferential walls of a vertical pair of casings 1 and 2 for forming an electric and electronic apparatus such as a cellphone, and an elastic body 5 consisting of silicone rubber to be elastically in contact with the opposed ribs 3 of the casings 1 and 2 is screen printed on both upper and lower surfaces of the base material 4 in an endless frame shape. Since the elastic body 5 is integrally composed to the base material 4 having stable properties to form the gasket, the rigidity, shape stability and handling property of the gasket are remarkably improved, and it is also expectable that the positioning work or assembling work can be performed further more smoothly, quickly and easily.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gasket for an electric / electronic device used for a portable telephone or the like.

[0002]

2. Description of the Related Art In recent years, various functions have been required for electric and electronic devices such as mobile phones which have been actively researched and developed. One of them is a dustproof and waterproof function. When a dustproof or waterproof function is provided to this type of electric / electronic device, (1) a pair of upper and lower housings 1 and 2 forming the electric / electronic device
When assembling, a method of interposing a frame-like gasket 10 made of various rubbers between these opposing opening peripheral surfaces to absorb slight irregularities and gaps in the frame-like gasket 10
(See FIG. 7), (2) a string-like gasket 11 (see FIG. 8) made of various rubbers is stretched and attached to the peripheral surface of the opening of one housing 2,
Thereafter, a method of assembling the pair of housings 1 and 2 and compressing the string-like gasket 11 with them to absorb irregularities and gaps in the string-like gasket 11 is used.

[0003] (3) The housings 1 and 2 of the electric and electronic equipment are A
In the case of a synthetic resin such as BS or PC, as shown in FIG. 9, two colors of an olefin-based elastomer 12 are molded on the peripheral surface of the opening of one housing 2 and then a pair of housings 1 and 2 are assembled. A method is adopted in which the elastomer 12 inserted therein is compressed, and the elastomer 12 absorbs fine irregularities and gaps.

[0004]

Conventionally, the above-described methods have been employed to provide a dust-proof or waterproof function to electric and electronic equipment such as a cellular phone. There's a problem. First, in the case of the methods (1) and (2), the rubber frame-shaped gasket 10 and the string-shaped gasket 11 are simply interposed between the opening peripheral surfaces of the pair of housings 1 and 2, so that the rigidity and the shape are reduced. The stability is very poor, which may cause difficulty in assembling, or may make assembly impossible at worst. Further, in the case of the method (3), although the problems of the methods (1) and (2) can be solved to some extent, since the synthetic resin and the elastomer 12 are combined and integrated, materials such as heat resistance can be used. Is very limited. Also, it is actually difficult to adjust the hardness of the elastomer 12.
In addition, burrs are generated on the parting line of the mold during molding of the housings 1 and 2, and a large problem that the cost of the product and the mold becomes extremely high is newly caused.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and improves rigidity, shape stability and assemblability, can easily adjust hardness, and can reduce the cost of products and the like. It is intended to provide a gasket for electric and electronic equipment.

[0006]

According to the present invention, in order to achieve the above object, a gasket is provided between a plurality of housings forming an electric / electronic device.
A base material is sandwiched between the opposing ribs of the plurality of housings, and elastic bodies that are in contact with the opposing ribs of the housings are provided on both surfaces of the base material in substantially endless linear shapes.

[0007] The base material may be a polyester resin film, and the elastic body may be silicone rubber. Further, an electromagnetic wave generation source is provided on the base material, and a conductive layer is formed on the inner surface of the housing covering the electromagnetic wave generation source so that the conductive layer can be brought into contact with the elastic body, and the conductive particles are dispersed in the elastic body. It can also be blended.

Here, the electric and electronic equipment in the claims includes at least OA equipment, cordless phones, portable telephones, electric switches, remote control switches and the like. The linear shape of the elastic body includes a linear shape, a band shape, a shape similar to these, and the like. The cross-sectional shape of this elastic body is substantially semi-circular, substantially rectangular, substantially semi-track, substantially semi-elliptical,
Or, a shape similar to these can be used.

According to the first aspect of the present invention, OA equipment,
When assembling electric and electronic devices such as radios, mobile phones, electrical switches, and remote control switches, a gasket base material with good shape stability is interposed between the opposing ribs of multiple housings. The elastic bodies such as the polymerized elastic bodies are compressed to absorb irregularities and gaps between the opposing ribs. The dust-proof, drip-proof and water-proof functions of the electric and electronic equipment are ensured by this absorbing action.

According to the invention of claim 2, polyethylene terephthalate, polybutylene terephthalate, 1,4-cyclohexyl dimethylene terephthalate, polyethylene naphthalate, PET / P
Since a polyester resin film made of BT, PET / PC, etc. is used, it has high tensile strength, excellent dimensional stability, flex resistance, and electrical insulation, and a temperature of approximately −20 to 80 ° C. The flexibility and mechanical properties hardly change within the range. Among these polyester resin films, 1,4 cyclohexyl dimethylene terephthalate and polyethylene naphthalate can be expected to have high heat resistance. When polyethylene terephthalate is selected, since polyethylene terephthalate is crystalline, it is stable to light and heat, and has high resistance to acids, weak alkalis, and oxidizing agents. Further, since silicone rubber is used as the elastic body of the gasket, it has excellent heat resistance and cold resistance, and can be used in a wide temperature range. Further, since there are few double bonds in the material components, excellent weather resistance, ozone resistance, and electrical characteristics can be obtained.

According to the third aspect of the present invention, the conductive layer of the housing electrically connected to the conductive elastic body reflects and attenuates or attenuates unnecessary electromagnetic waves from the electromagnetic wave generation source, thereby reducing the size of the housing. Contain electromagnetic waves. Therefore, it is possible to effectively protect the components of the electric / electronic device from electromagnetic waves, radio waves, and magnetic fields.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of the present invention will be described below with reference to the drawings. A gasket for an electric / electronic device according to the present embodiment is shown in FIGS. 1, 2 (a) and 2 (b). As described above, the base member 4 is sandwiched between the opposing ribs 3 which are the peripheral walls of the pair of upper and lower housings 1.2 forming an electric / electronic device such as a mobile phone. Each of the wide elastic members 5 elastically contacting with 3 is printed in a frame shape.

The pair of housings 1 and 2 are formed by using a PC or the like having good strength, dimensional accuracy, impact resistance, and electrical characteristics. A plurality of locking claws (not shown) and screw holes (not shown) are appropriately formed on the opposing ribs 3 and the like of the other housing 1, and these screw holes are engaged at the time of assembling or screwed into a fastener (not shown). You. The material of the housings 1 and 2 is mainly made of PC, but is not limited thereto. For example, ABS, PA, P
ES or the like can also be used.

The substrate 4 is formed in a thin frame shape using a polyester resin film, a polyimide film, or the like having excellent dimensional stability and the like. Further, the elastic body 5 is made of, for example, silicone rubber, NBR, styrene butadiene rubber, ethylene propylene rubber, fluorine rubber, or the like, and is screen-printed in a substantially semi-elliptical cross section to fit the pair of housings 1 and 2 together. The elastic modulus and the thickness that can absorb the dimensional tolerance (general dimensional tolerance) of about 0.1 mm at the time are secured. When the elastic body 5 is made of liquid rubber, a liquid rubber having elastic properties is drawn in a frame shape on the base material 4, and the liquid rubber is heated and hardened to form the elastic body 5.

In the above configuration, when the electric and electronic equipment is to be provided with a dust-proof and water-proof function, when the pair of housings 1 and 2 are overlaid and assembled, the opening of the opposing rib 3 of the pair of housings 1 and 2 facing each other. The base member 4 is interposed between the peripheral surfaces, the pair of housings 1 and 2 are assembled with screws or the like, and the elastic members 5 of the base member 4 are crushed. What is necessary is just to fill the slight irregularities and gaps between them.

According to the above configuration, the base material 4 having stable properties
Since the gasket is formed by integrating the elastic body 5 into the gasket, the rigidity, shape stability, and handleability of the gasket are remarkably improved, and the positioning operation and the assembling operation can be greatly facilitated, speeded up, and facilitated. . Further, since the separate elastic body 5 made of silicone rubber or the like is screen-printed on the base material 4, the adjustment of the hardness of the elastic body 5 is very easy, and the housing 1
No burrs are generated on the parting line of the mold during the molding of 2, and the problems of extremely high cost of the product and the mold are not caused. Further, the material is not limited from the viewpoint of heat resistance and the like. Further, since the elastic body 5 has a thick band shape corresponding to the cross-sectional shape of the opposing rib 3, uniformity of the compression distribution of the elastic body 5 and improvement of the degree of adhesion can be greatly expected. Furthermore, since a simple screen printing method is used to form the elastic body 5, it is possible to simplify the operation, reduce the printing pressure, or increase the thickness of the elastic body layer.

FIGS. 3 (a) and 3 (b) show a second embodiment of the present invention. In this case, the base material 4A is a flexible printed circuit board, The outer periphery of the base material 4A on which the base 6 is formed is extended outwardly and sandwiched between the opposing ribs 3 of the pair of housings 1 and 2, and the outer periphery of the upper and lower surfaces of the base material 4A is Each of the elastic members 5 elastically contacting the ribs 3 is screen-printed in a frame shape. The other parts are the same as those in the above-described embodiment, and a description thereof will be omitted. It is apparent that the same effects as those of the above embodiment can be expected in this embodiment, and that the number of parts can be reduced by omitting the base material 4 and the elastic body 5 which are dedicated products. Also,
This is extremely useful when it is difficult to sandwich the base material 4 made of a PET film or the like between the opposing ribs 3 of the pair of housings 1 and 2.

Next, FIGS. 4A and 4B show a third embodiment of the present invention. In this case, the base material 4B is not shown as a plurality of rubber key members 7. A resin film having a circuit pattern is provided, and the outer peripheral portion of the base material 4B is extended outward to be sandwiched between the opposing ribs 3 of the pair of housings 1 and 2, and the outer peripheral portions of the upper and lower surfaces of the base material 4B are formed. Is enclosure 1
Each of the elastic members 5 elastically contacting the two opposing ribs 3 is screen-printed in an endless frame shape. The other parts are the same as those in the above-described embodiment, and a description thereof will be omitted.

FIGS. 5 (a) and 5 (b) show a fourth embodiment of the present invention. In this case, a plurality of elastic ribs are provided on the upper surface of the base member 4 so as to be in contact with the opposing ribs 3 of the housing 1. FIG. Each of the elastic members 5 is screen-printed in a thin frame shape, and a plurality of elastic members 5 elastically in contact with the opposing ribs 3 of the housing 2 are also screen-printed in a thin frame shape on the lower surface of the substrate 4. The plurality of elastic bodies 5 on each surface of the substrate 4 are formed in the same cross-sectional shape or different cross-sectional shapes as necessary. The same applies to the thickness of the plurality of elastic bodies 5. The other parts are the same as those in the above-described embodiment, and a description thereof will be omitted. In this embodiment, the same operation and effect as those of the above embodiment can be expected, and moreover, a plurality of large and small elastic bodies 5 having different sizes are formed in a fitted state inside and outside each surface of the base material, so that dust-proofing of the electric / electronic equipment is prevented. It is clear that the waterproof function can be greatly enhanced.

FIGS. 6 (a) and 6 (b) show a fifth embodiment of the present invention. In this case, a signal transmitting portion and the like are formed on a base material 4A made of a flexible printed circuit board. A plurality of electromagnetic wave sources 8 are mounted, and a thin conductive layer 9 is formed on the inner surface of the housing 1 covering the electromagnetic wave source 8 by a vapor deposition method, a sputtering method, or the like.
The conductive particles are dispersed and blended into the elastic body 5. As the conductive particles, silver particles, nickel particles, carbon fiber particles and the like are used. The other parts are the same as those in the above-described embodiment, and a description thereof will be omitted. In this embodiment, the same operation and effect as those of the above embodiment can be expected, and furthermore, since the electromagnetic wave from the electromagnetic wave generation source 8 can be shielded, malfunction of the electronic component is induced or normal function is deteriorated. Nothing.

In the above embodiment, a pair of upper and lower housings 1 is provided.
-Although 2 was shown, it is not limited to this. For example, the housing 1 may be single or may be divided into a plurality. Further, the elastic body 5 may or may not be completely frame-shaped. The elastic body 5 is preferably completely endless, but may be substantially recognized as endless as long as the dustproof and waterproof functions can be ensured. Further, the above embodiments can be combined as appropriate. For example, the base material 4 of the fourth embodiment
Can be used as the base material 4A of the second embodiment or the base material 4B of the third embodiment.

[0022]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of a gasket for electric and electronic equipment according to the present invention will be described below. Example 1 First, a base material 4 having a thickness of 75 μm was annealed to remove distortion and the like, and the base material 4 was formed in a predetermined shape, and an alignment hole was formed in a predetermined position of the base material 4 in a predetermined shape. The substrate 4 was punched, and the substrate 4 was set on a screen printer. As the substrate 4, a polyester film (Lumirror, manufactured by Toray Industries, Inc.) was used.

After the substrate 4 was set on the screen printing machine, a plurality of elastic bodies 5 were printed on the upper surface of the substrate 4 in a frame shape by silk screen printing. As the elastic body 5,
Silicone-based RTV rubber (trade name: KE-1800, manufactured by Shin-Etsu Chemical Co., Ltd.) was used in a ratio of 100 parts by weight of liquid A, 10 parts by weight of liquid B, and 2 parts by weight of liquid C. The plurality of elastic bodies 5 are arranged in two rows, and the interval between the rows is 0.
5 mm. Each elastic body 5 has a width of 0.5 mm and a thickness of 100
μm. The thickness of the silk screen emulsion is 10
It was set to 0 μm.

After a plurality of elastic members 5 were screen-printed on the upper surface of the substrate 4, the substrate 4 was taken out from the screen printer, and the substrate 4 was set in an infrared hot air oven at 90 ° C. for 5 minutes and dried. Then, the same operation as the above operation was performed on the lower surface of the base material 4, and these operations were repeated twice to produce a gasket for an electric / electronic device. When the characteristics of the gasket for electric and electronic devices thus manufactured were confirmed, the width of the elastic body 5 inside the base material 4 was 0.74 mm, the width of the outer elastic body 5 was 0.83 mm,
The thickness of the gasket including the base material 4 was 0.58 mm, and the hardness of the elastic body 5 was 35 ° (JIS A).

Next, using a resin, the length is 90 mm and the width is 6 mm.
A simple casing 2 having a thickness of 0 mm and a height of 20 mm was molded, and a flat plate having a thickness of 3 mm was simply molded using the same resin, and a gasket for an electric / electronic device manufactured between the casing 2 and the flat plate was sandwiched. Thereafter, screws having a diameter of 2 mm were screwed into the four corners of the housing 2 and the flat plate, respectively, to test the waterproofness. As a result of the test, extremely good waterproofness was confirmed. Although the rib width of the housing 2 was set to 3 mm, positioning at the time of mounting was very simple, and positioning could be performed in only a few seconds.

Example 2 First, a flexible printed circuit board having a thickness of 0.35 mm was used as a base material 4A. The base material 4A was formed in a predetermined shape, and an alignment hole was formed in a predetermined position of the base material 4A in a predetermined shape. The substrate 4A was set in a screen printer. The base material 4A was gold-plated after copper etching on a polyimide film having a thickness of
It was manufactured by forming a wiring layer of μm in a linear pattern having a pitch of 0.5 mm and a pitch of 1 mm.

After setting the substrate 4A on the screen printing machine, a plurality of elastic bodies 5 were printed in a frame shape on the upper surface of the substrate 4A by silk screen printing. As the elastic body 5, a rubber obtained by diluting a conductive silicone-based RTV rubber (trade name: KE-3492, manufactured by Shin-Etsu Chemical Co., Ltd.) with kerosene to a volume ratio of 200% was used. The plurality of elastic bodies 5 are 2
The rows were arranged, and the interval between the rows was 0.5 mm. Each elastic body 5 has a width of 0.5 mm and a thickness of 100 μm. The silk screen emulsion had a thickness of 100 μm.

After the plurality of elastic members 5 were screen-printed on the upper surface of the substrate 4A, the substrate 4A was taken out from the screen printing machine, and the substrate 4A was set in an infrared hot air oven at 90 ° C. for 5 minutes and dried. Then, the same operation as above was performed on the lower surface of the base material 4A, and these operations were repeated twice to produce a gasket for electric / electronic equipment. When the characteristics of the manufactured gasket for electric and electronic equipment were confirmed, the width of the elastic body 5 inside the base material 4A was 0.68 mm, the width of the elastic body 5 outside was 1.12 mm,
The thickness of the gasket including the base material 4A was 1.05 mm, and the hardness of the elastic body 5 was 50 ° (JIS A).

Next, using a resin, the length is 90 mm and the width is 6 mm.
A simple case 2 having a thickness of 0 mm and a height of 20 mm is formed, a flat plate having a thickness of 3 mm is formed easily using the same resin, and a conductive layer 9 is formed on the inner surface of the flat plate, which is a rear surface. And the flat plate and the produced gasket for electric and electronic equipment are sandwiched between them.
Each screw having a diameter of m was screwed and tested for waterproofness.
As a result, a very good waterproof property could be obtained. Although the rib width of the housing 2 was set to 3 mm, positioning at the time of mounting was extremely simple, and positioning could be performed in a few seconds. As for the conductivity, a value of 15Ω or less could be obtained between the elastic patterns, and a current could smoothly flow from the flat plate having the conductive layer 9 on the inner surface to the base material 4A.

[0030]

As described above, according to the first aspect of the present invention, the base material is sandwiched between the opposing ribs of the plurality of housings, and the elastic members that are in contact with the opposing ribs of the housing are substantially provided on both surfaces of the base material. Since the gasket is provided in an endless linear shape, the rigidity, shape stability, and assemblability of the gasket can be improved. Further, the hardness of the elastic body can be easily adjusted, and furthermore, it is possible to reduce the product cost and the like of the electric / electronic device. According to the invention as set forth in claim 3, an electromagnetic wave generation source is provided on the base material, and a conductive layer is formed on an inner surface of a housing covering the electromagnetic wave generation source so that the conductive layer can be brought into contact with the elastic body;
Since the conductive particles are dispersed and blended in the elastic body, the electromagnetic waves from the electromagnetic wave generation source can be shielded. Therefore, it is possible to suppress malfunctions of the components of the electric / electronic device and to suppress a decrease in the normal function of the electric / electronic device.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional explanatory view showing an embodiment of a gasket for an electric / electronic device according to the present invention.

FIG. 2 is a schematic explanatory view showing an embodiment of a gasket for an electric / electronic device according to the present invention, wherein FIG. 2 (a) is a perspective view and FIG.
FIG. 3 is a sectional view taken along line bb in FIG.

FIG. 3 is a schematic explanatory view showing a second embodiment of a gasket for an electric / electronic device according to the present invention, wherein FIG. 3 (a) is a perspective view, and FIG.
The figure is a sectional view taken along the line bb in FIG.

FIG. 4 is a schematic explanatory view showing a third embodiment of a gasket for an electric / electronic device according to the present invention, wherein FIG. 4 (a) is a perspective view, and FIG.
The figure is a sectional view taken along the line bb in FIG.

FIG. 5 is a schematic explanatory view showing a fourth embodiment of the gasket for electric / electronic equipment according to the present invention, wherein FIG. 5 (a) is a perspective view, and FIG.
The figure is a sectional view taken along the line bb in FIG.

FIG. 6 is a schematic cross-sectional explanatory view showing a fifth embodiment of a gasket for an electric / electronic device according to the present invention.

FIG. 7 is an exploded perspective view showing a conventional housing and its frame-shaped gasket.

FIG. 8 is a perspective explanatory view showing a conventional string-shaped gasket.

FIG. 9 is an explanatory perspective view showing a conventional two-color molded housing.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 housing 2 housing 3 opposing rib 4 base material 4A base material 4B base material 5 elastic body 6 circuit pattern 7 key member 8 electromagnetic wave generation source 9 conductive layer

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Hitoshi Ando 4-5-2 Nihonbashi Honcho, Chuo-ku, Tokyo Shin-Etsu Polymer Co., Ltd. F-term (reference) 3J040 AA01 AA12 BA01 EA15 EA17 EA25 FA06 HA15 4E360 AB02 AB13 AB33 BA02 BA08 BC05 CA02 ED07 ED23 ED27 FA02 FA09 GA11 GA34 GA52 GA53 GB97 GC08

Claims (3)

[Claims] 1. A gasket for an electric / electronic device having a gasket provided between a plurality of housings forming an electric / electronic device, wherein a base material is sandwiched between opposing ribs of the plurality of housings, and is provided on both surfaces of the base material. A gasket for an electric / electronic device, wherein elastic bodies that come into contact with opposed ribs of the housing are provided in substantially endless linear shapes. 2. The gasket according to claim 1, wherein said base material is a polyester resin film, and said elastic body is silicone rubber. 3. An electromagnetic wave generating source is provided on the base material, and a conductive layer is formed on an inner surface of the housing covering the electromagnetic wave generating source so that the conductive layer can be brought into contact with the elastic body. 3. The gasket for an electric / electronic device according to claim 1, wherein the particles are dispersed and blended.