JP2801180B2 - Gasket for electromagnetic wave shielding - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gasket for shielding electromagnetic waves, which is sandwiched between gaps of a conductive casing and shields electromagnetic waves passing through the gap.

[0002]

2. Description of the Related Art Conventionally, as this kind of gasket for electromagnetic wave shielding, for example, as shown in FIG. 5 (A), an end of the gasket is formed around a side surface of a core material 32 formed in a rod shape by an elastic material. Conductive cloth 34 woven by conductive fibers
(For example, U.S. Pat. No. 4,857,668).

In addition, instead of the above-described conductive cloth 34, there has also been proposed one in which a wire mesh is covered around the side surface of the core material 32 (for example, Japanese Patent Application Laid-Open No. 2-296396).

[0004]

However, the above-described conventional gaskets for shielding electromagnetic waves (hereinafter, also simply referred to as gaskets) have the following problems. First, when the core material 32 is formed of a material such as a sponge or the like whose volume itself becomes small when compressed, the gasket is formed of the conductive casings 36a and 36b as illustrated in FIG. 5B. When used in a gap,
The core material 32 tries to shrink entirely in the compression direction.
Since the surface on the side not in contact with the second conductive casings 36a and 36b cannot be shrunk by the conductive cloth 34 or the wire mesh, the conductive cloth 34 or the wire mesh is eventually placed inside the compressed core material 32. As a result, the conductive cloth 34 and the wire mesh are creased and deteriorated. In an extreme case, the conductive cloth 34 or the wire mesh may be cracked, and the original shielding effect may not be obtained.

[0005] Further, when such a gasket is mounted on the mating portion of the conductive casing that opens and closes, the core material 32 is deformed by the folds generated in the conductive cloth 34 and the wire mesh, and the elasticity of the gasket itself is increased. That is, there is a problem that the restoring force gradually decreases, and the adhesion to the conductive housing deteriorates.

On the other hand, when the core material 32 is made of a material such as elastic rubber whose volume itself does not change much when compressed, the gasket is made of a conductive casing as shown in FIG. When used between the gaps 36a and 36b, the core material 32 shrinks not only in the compression direction but also expands in the direction perpendicular to the compression direction. There is a problem that stress is generated and the durability of the conductive cloth 34 and the wire mesh is reduced.

When such a gasket is mounted on the mating portion of the conductive casing which opens and closes, the core material 32 and the conductive material are opened and closed by the above-mentioned stress while the conductive casing is opened and closed many times. There is also a problem that a positional shift occurs with the cloth 34 or the like, the shape of the gasket itself does not return to its original shape, and the adhesion to the conductive housing deteriorates.

On the other hand, when a conductive cloth 34 or a wire mesh woven with conductive fibers is used as the conductive covering material as in the above-mentioned conventional gasket, the conductive covering material and the conductive casing are used. Do not make complete surface contact, and there is a limit to complete conduction between the gaps and the mating portions of the conductive housing. In addition, when the conductive cloth 34 is used as the conductive covering material, fine dust is generated from the conductive cloth 34, and when the wire mesh is used as the conductive covering material, the metal of the wire mesh is used. Since dust or pollen in the air may enter between the wires, it cannot be used in a clean room such as a semiconductor factory.

The present invention has been made in view of such problems, and has excellent durability and shape restoring properties.
It is an object of the present invention to provide a high-performance electromagnetic shielding gasket that can be used anywhere.

[0010]

That Means for Solving the Problems] The present invention according to claim 1 which has been made in order to achieve the above object, Ri by <br/> the elastic member, core cross-section is formed in a columnar shape of a rectangle Material, and a sheet-shaped conductive covering material covered around the side surface of the core material, and for shielding electromagnetic waves sandwiched by a gap between one side and the other side of the conductive housing. In the gasket, the conductive coating material is formed by laminating a metal layer on a film material made of synthetic resin ,
Its two side edges meet at the center of one side of the core
Wrapped around the side of the core so that the conductive
The covering material and the core material are the four side surfaces of the core material.
In this case, the side surface where the both side edges are aligned and the side surface are opposite.
It is glued only on the two sides with the opposite side.
In the conductive coating material, both side edges were matched
On the surface of the mating portion opposite to the core material, the core material
A double-sided adhesive tape that is narrower than the width covers the mating part.
The electromagnetic wave shielding gasket.
The double-sided adhesive tape secures the conductive casing.
The present invention provides a gasket for electromagnetic wave shielding , which is bonded and fixed to one side .

[0011]

In the gasket for shielding electromagnetic waves according to the present invention , the sheet-shaped conductive coating material is provided on both sides thereof.
One turn so that the edges meet at the center of one side of the core
Wrapped around the side of the core material with conductive coating
The adhesive between the core and the core is made of the conductive material on the four sides of the core.
The side where the both edges of the cladding material meet and the side
It is considered on two sides, the opposite side. Soshi
With conductive coating material,
The surface opposite to the core of the wedging part (that is,
On the opposite side), both sides are narrower than the width of the core
An adhesive tape is stuck so as to cover the mating portion.
You.

[0012] Such a gas for shielding electromagnetic waves of the present invention.
The bracket is a double-sided adhesive tape attached to the surface of the conductive coating material.
Adhesive on one side of the conductive housing
In the gap between one side of the conductive housing and the other side
You. Then, due to the elasticity of the core material formed of the elastic material, the conductive coating material covered around the side surface comes into close contact with the conductive housing and passes through the gap between one side and the other side of the conductive housing. Ru Nodea that it is possible to shield the electromagnetic waves. In addition, both
Since the width of the surface adhesive tape is smaller than the width of the core material,
The covering material can be securely brought into close contact with the conductive housing.

Here, in the electromagnetic wave shielding gasket of the present invention , the conductive covering material and the core material are made of four core materials.
The sides of the conductive coating material are aligned
Side and the side opposite to the side
Because you have to look bonding, only the inner both surfaces in contact with the conductive housing of the electrically conductive coating material is adhered to the core material
Te, the surface not in contact with the conductive housing in those the gasket, the conductive coating material and the core material and is not bonded.

Therefore, according to the gasket for electromagnetic wave shielding of the present invention , when the core material is formed of a material such as sponge, the volume of which itself becomes small when compressed, the gasket is formed by the conductive casing. Even if compressed,
Conductive coating material that will be bent inward of the core
Since the conductive coating material is gradually curved outward without deterioration , the conductive coating material does not deteriorate. Further, since the core material can expand and contract in a well-balanced manner without being hindered by the conductive coating material, the original elasticity of the gasket can be maintained for a long period of time. There is no deterioration in adhesion to the housing.

When the core material is made of a material such as elastic rubber whose volume itself does not change much when compressed, the gasket is compressed by the conductive casing and the core material becomes conductive. even bulge on the side not in contact with the body, the adhesion and the core member and the conductive covering material at its face side not
There therefore, both the positional relationship is not applied extra stress to the conductive coating material was varied smoothly. Then, when the gasket is no longer compressed, the positional relationship between the core material and the conductive coating material quickly returns to the original state, so that the resilience of the gasket itself does not decrease.

That is, according to the gasket for shielding electromagnetic waves of the present invention , excellent durability and resilience can be obtained irrespective of the expansion and contraction characteristics of the core material. And the book
In the gasket for shielding electromagnetic waves according to the present invention, the conductive coating material is formed by laminating a metal layer on a film material made of synthetic resin.

[0017] Thus, a conductive housing and the conductive coating material can be completely surface contact with the metal layer, between gap of the conductive housing to be able to conduct at lower resistance state . And since the conductive coating material is formed by laminating a metal layer on a film material made of synthetic resin, even if the gasket is compressed due to its flexibility, it is possible to prevent the metal layer from being cracked, Also, even if a crack occurs in the metal layer, the crack remains only partially and does not spread.

Further, since the conductive coating material is formed by laminating a metal layer on a synthetic resin film material,
No fine dust is generated from the conductive coating material, and no foreign matter such as dust or pollen in the air adheres to the conductive coating material. Thus, according to the electromagnetic shielding gasket, as in the semiconductor factory of the clean room, such as dust from entering Ru it can be used safely in place do not.

In addition, the gasket for electromagnetic wave shielding of the present invention
In the unit, the gasket is fixedly adhered to the conductive casing
Double-sided adhesive tape to cover the mating part of the conductive coating material.
It is provided as follows. For this reason, double-sided adhesive tape
It is the role of bonding and fixing the gasket to the conductive case
But not the joints of the conductive coating
It will also play a role.

Therefore, the gasket for electromagnetic wave shielding of the present invention
According to the sheet, a conductive coating material is wound around the side of the core material.
And can be manufactured with
It does not require the addition of special reinforcing members
And high durability can be obtained. In addition, the power supply of the present invention
Magnetic shield gaskets do not touch conductive enclosure
Do not bond the conductive coating and the core only on the surface.
Of both surfaces of the conductive coating material that contact the conductive housing.
Since the side is bonded to the core material, durability is further improved
Can be.

As described above, according to the gasket for shielding electromagnetic waves of the present invention , although it can be easily manufactured,
Not, it is possible to obtain a superior durability and resilience, a high performance that can conduct between gap of the conductive enclosure with lower resistance state, can exhibit everywhere.

[0022]

Embodiments of the present invention will be described below with reference to the drawings. First, FIG. 1 is an explanatory diagram for explaining a configuration of an electromagnetic wave shielding gasket of a first embodiment to which the present invention is applied.

As shown in FIG. 1A, the electromagnetic shielding gasket 2 of this embodiment is made of an elastic foam material (for example, a member formed of sponge-like chloroprene or polyurethane), and has a rectangular cross section. And a sheet-like conductive covering material 6 provided around the side surface of the core material 4.

As shown in FIG. 1B, the conductive coating material 6 is formed by laminating a polyvinyl chloride (PVC) 8, a polyethylene terephthalate (PET) 10, and an aluminum foil 12, respectively. The thickness of each material is 100 μm for PVC 8, 25 μm for PET 10, and 12 μm for aluminum foil 12, respectively.

The conductive coating material 6 is gently wound around the core material 4 so that both side edges in the unfolded state meet at the center of the upper surface of the core material 4 in FIG. The material 4 is adhered and fixed by double-sided adhesive tapes 14 and 16 attached to the bottom surface and the upper surface, respectively. Further, a double-sided adhesive tape 18 for attaching the gasket 2 to a conductive casing to be described later is attached to a surface of the conductive coating material 6 on the mating portion 17 side. Is set to be smaller than the width. And double-sided adhesive tape 18
A release paper 20 is adhered to the surface of.

As shown in FIG. 1A, the width of the double-sided pressure-sensitive adhesive tapes 14, 16 for bonding the core material 4 and the conductive coating material 6 is formed to be substantially the same as the width of the core material 4. However, it may be set smaller than the width of the core material 4. The reason why the conductive coating material 6 is gently wound around the core material 4 is to prevent the conductive coating material 6 from being stressed. Therefore, on the two surfaces where the conductive coating material 6 is not adhered to the core material 4, a slight clearance is provided between the conductive coating material 6 and the core material 4 as shown in FIG. .

The gasket 2 configured as described above is
For example, as shown in FIG.
Is adhered and fixed to the main body 22a as one side by a double-sided adhesive tape 18 from which the release paper 20 has been peeled off. And
In this state, as shown in FIG. 2 (B), other conductive enclosure
When the lid 22b as one side is closed in the direction of the arrow, the gasket 2 is compressed, and the conductive coating material 6 comes into close contact with the main body 22a and the lid 22b of the conductive housing, respectively.
Electromagnetic waves that pass between the joints (that is, gaps) between the lid and the lid 22b are cut off.

In the gasket 2 of this embodiment,
Since the width of the double-sided adhesive tape 18 to be attached to the main body portion 22a of the conductive housing is smaller than the width of the core material 4,
When the lid 22b of the conductive casing is closed, as shown in FIG. 2 (B), the conductive coating material 6 securely adheres to the main body 22a of the conductive casing.

Here, in the gasket 2 of the present embodiment, the core material 4 and the conductive coating material are not provided on the surface of the conductive casing which does not contact the main body portion 22a and the lid portion 22b, that is, on the left and right surfaces in FIG. 6 is not bonded. Therefore, when the lid 22b of the conductive casing is closed, as shown in FIG. 2B, the conductive covering material 6 is gently curved outward without being bent inside the core material 4. Therefore, even if the lid 22b of the conductive casing is repeatedly opened and closed, the conductive covering material 6 does not deteriorate. In addition, since the core member 4 can be entirely expanded and contracted in the compression direction without being hindered by the conductive coating member 6, the original elasticity of the gasket 2 is maintained for a long period of time. And the adhesion between the main body portion 22a and the lid portion 22b of the conductive housing does not deteriorate.

Moreover, in the gasket 2 of this embodiment, since the surface of the conductive coating material 6 is an aluminum foil 12,
The conductive covering material 6, the main body 22a of the conductive housing, and the lid 2
The contact with the surface 2b is performed on the surface, so that the body 22a and the lid 22b can be more reliably conducted. The conductive coating material 6 has sufficient flexibility due to the PET 10 and the PVC 8 laminated on the inner side of the aluminum foil 12 and thus has excellent durability.

Further, since the conductive coating material 6 is formed by laminating the aluminum foil 12 on the PVC 8 and PET 10, fine dust is generated from the conductive coating material 6 or air is applied to the conductive coating material 6. No foreign matter such as dust or pollen inside adheres. Thus, according to the gasket 2, as in the semiconductor factory clean room, Ru can also be used in places where dust and the like must not be invaded.

In addition, in the gasket 2 of this embodiment,
Double-sided adhesive for mounting the gasket 2 on a conductive casing
As shown in FIG. 1A, the tape 18 is
It is provided so as to cover the contact portion 17. For this reason,
The adhesive tape 18 adheres the gasket 2 to the conductive casing.
Not only the role of fixing, but also the
It also plays the role of reinforcing the joining of the contact portion 17.
You.

Therefore, according to the gasket 2 of this embodiment,
It is manufactured by simply winding the conductive coating material 6 around the side surface of the core material 4.
And with such a simple configuration
High resistance without adding special reinforcement
You can gain longevity. In addition, the gasket of the present embodiment
In No. 2, contact is made between the main body 22a and the lid 22b of the conductive housing.
Do not bond the conductive coating material 6 and the core material 4 only on
And the surface of the conductive coating material 6 that contacts the conductive housing.
Inside of both are cored by double-sided adhesive tapes 14,16
Because it is bonded to the material 4, the durability can be further improved.
Wear.

As described above, the gasket 2 of this embodiment
According to it, despite being easy to manufacture,
Durability and resilience, and
The gap in the housing can be conducted with lower resistance
The high performance of that, be exhibited in Shin'yu Ru location
Wear.

[0035] In the embodiments described above, the chloroprene or polyurethane or the like to form the core member 4 by using a foam with a formed resilient spongy, elastic rubber such as a core 4, is compressed It may be formed of a material whose volume itself does not change much when it is formed. And in this case,
When the lid 22b of the conductive casing is closed, the core material 4 swells to the side not in contact with the main body part 22a and the lid 22b of the conductive casing. Since the coating material 6 is not bonded , the positional relationship between the two changes smoothly, so that no extra stress is applied to the conductive coating material 6. Further, when the lid 22b of the conductive casing is opened, the positional relationship between the core member 4 and the conductive covering material 6 returns to the original state promptly, so that the resilience of the gasket 2 itself does not decrease. is there.

Here, according to the gasket 2 of the first embodiment, the above-described excellent effects can be obtained. However, when the gasket 2 is mounted on a conductive casing, the gasket 2 is not used.
If a large bending stress is applied in the longitudinal direction, the aluminum foil of the conductive coating material 6 may be cracked.

Then, as a second embodiment, a gasket for electromagnetic wave shielding which can solve such a problem in handling will be described. As shown in FIG. 3A, the gasket 24 of the present embodiment is configured in exactly the same manner as the gasket 2 of the first embodiment, but the conductive coating 6
The only difference is that the cuts 26 are provided at equal intervals in advance on the two surfaces that are not in contact with the conductive casing.

The cut 26 is formed in the gasket 2
4 is provided in a direction perpendicular to the longitudinal direction,
Even if a bending stress is applied in the longitudinal direction of the gasket 24, the gasket 24 bends at the position of the cut 26, so that there is no fear that an unexpected crack is generated in the conductive coating material 6.

The gasket 2 constructed as described above
According to No. 4, even when the surface of the conductive casing that comes into contact has some irregularities, the surface of the conductive coating material 6 is easily deformed in accordance with the irregularities, so that the adhesion between the two may be impaired. Absent. Further, the operation of cutting the gasket 24 to a desired length becomes very easy.

Here, the gasket 24 illustrated in FIG. 3A has cuts 26 in two surfaces on the side not in contact with the conductive housing.
However, as shown in FIG. 3B, the cuts 26 may be provided on three surfaces of the conductive coating material 6 other than the surface on which the double-sided adhesive tape 18 is adhered.

The reason why the notches 26 are not provided on all four surfaces of the conductive coating material 6 is that the conductive coating material 6 has the cuts 2
This is because it is assumed that, after inserting the core material 4, the core material 4 is wound around the core material 4. For example, when the conductive coating material 6 is wound around the core material 4 and then the cut 26 is provided, the Ru can be in all surface incision 26.

The first embodiment and the second embodiment described above
In the gaskets 2 and 24 of the second embodiment, the conductive coating
In order not to give extra stress to the material 6, the conductive coating material
6 and the core material 4 are not bonded to each other on the two surfaces.
Although it was designed to provide dry clearance,
When the conductive coating material 6 has greater elasticity,
Connects the conductive coating material 6 and the core material 4 as shown in FIG.
Try to eliminate the clearance between the two sides
You may.

[0043] Also, in the gasket 2, 24 of the first and second embodiments, in terms of both the conductive coating material 6 is in contact with the conductive housing, the core 4 and the conductive coating material 6 And were bonded by double-sided adhesive tapes 14 and 16,
The adhesive is of course, not good even by adhesive.

[Brief description of the drawings]

FIG. 1 is an explanatory view illustrating a gasket for shielding electromagnetic waves according to a first embodiment.

FIG. 2 is an explanatory diagram illustrating a usage state of the electromagnetic wave shielding gasket of the first embodiment.

FIG. 3 is an explanatory view illustrating a gasket for an electromagnetic wave shield according to a second embodiment.

FIG. 4 is an explanatory diagram illustrating another embodiment.

FIG. 5 is an explanatory view for explaining a conventional electromagnetic shielding gasket.

[Explanation of symbols]

2,24 ... gasket for electromagnetic wave shielding 4,28
... core material 6 ... conductive coating material 8 ... polyvinyl chloride (PVC) 10 ... polyethylene terephthalate (PET) 12 ... aluminum foil 14,1 6,18 ... double-sided adhesive tape 17 ... mating portion

Claims (1)

(57) [Claims] 1. A Ri by the elastic member includes a cross-section core is formed in a columnar shape of a square material, and a sheet-like conductive coating material which is Kutsugae設around the sides of the core material, the conductive housing on one side and the electromagnetic shielding gasket for shielding the pinched electromagnetic waves in a gap between the other side of the body, the conductive coating material, as well is formed by laminating a metal layer on a film material made of a synthetic resin ,That
Both edges meet at the center of one side of the core
And the conductive covering material and the core material are wound around four sides of the core material.
Of the surfaces, the side surface where the both side edges are combined, and the side
Adhesive only on two sides, the side opposite to the side
In addition, both side edges thereof are joined by the conductive coating material.
The core material is provided on the surface of the mating portion opposite to the core material.
Double-sided adhesive tape narrower than the width of the
The electromagnetic shielding gasket is attached so as to cover the double-sided adhesive tape.
Adhesively fixed to one side of the conductive housing
And a gasket for shielding electromagnetic waves.