Title: Gasket and electronic apparatus having the same
Abstract: A gasket that serves to shield electromagnetic waves from an electronic apparatus that has a housing that includes a first surface and a second surface opposite to the first surface, the gasket being squeezed into a perforation hole that perforates the first and second surfaces, and fixed onto the housing includes a lid part that contacts the first surface and serves as a flat spring, and an insertion part that is to be inserted into the perforation hole in the housing, and includes an engagement part, coupled with the support part, which at least partially projects from the perforation hole in the housing and contacts the second surface, wherein the engagement part includes a leg coupled with the the support part, and a foot that is coupled with the leg and forms an acute angle relative to the leg.
Patent Number: 6,906,255 Issued on 06/14/2005 to Inoke, et al.
| Inventors:
|
Inoke; Misao (Kawasaki, JP);
Ueda; Satoshi (Kawasaki, JP)
|
| Assignee:
|
Fujitsu Limited (Kawasaki, JP)
|
| Appl. No.:
|
722121 |
| Filed:
|
November 26, 2003 |
Foreign Application Priority Data
| Dec 19, 2002[JP] | 2002-367762 |
| Current U.S. Class: |
174/35GC |
| Intern'l Class: |
H05K 009/00 |
| Field of Search: |
174/35 R,35.GC
361/816,818
277/920
|
References Cited [Referenced By]
U.S. Patent Documents
| 5001297 | Mar., 1991 | Peregrim et al.
| |
| 5313016 | May., 1994 | Brusati et al.
| |
| 5532428 | Jul., 1996 | Radloff et al.
| |
| 5569877 | Oct., 1996 | Yumi.
| |
| 6218611 | Apr., 2001 | Bias.
| |
| 6225555 | May., 2001 | Sosnowski.
| |
| 6320120 | Nov., 2001 | Van Haaster.
| |
| Foreign Patent Documents |
| 8-274485 | Oct., 1996 | JP.
| |
Primary Examiner: Ngo; Hung V.
Attorney, Agent or Firm: Westerman, Hattori, Daniels & Adrian, LLP
Claims
1. A gasket that serves to shield electromagnetic waves from an electronic apparatus
that has a housing that includes a first surface and second surface opposite to
the first surface, said gasket being squeezed into a perforation hole that perforates
the first and second surfaces, and fixed onto the housing, said gasket comprising:
a lid part that contacts the first surface and serves as a flat spring; and
an insertion part that is to be inserted into the perforation hole in the housing,
wherein the insertion part includes:
a support part that extends from an approximate center of said lid part and is
accommodated into the perforation hole; and
an engagement part, coupled with the support part, which at least partially projects
from the perforation hole in the housing and contacts the second surface,
wherein the engagement part includes:
a leg coupled with the support part; and
a foot that is coupled with the leg and forms an acute angle relative to the
leg.
2. A gasket according to claim 1, wherein the leg diverges from an approximate
center of the support part.
3. A gasket according to claim 2, wherein the support part has a projection opposite
to the perforation hole.
4. A gasket according to claim 1, wherein the leg extends from the support part
and forms an acute angle relative to the support part.
5. A gasket that serves to shield electromagnetic waves from an electronic apparatus
that has a housing that includes a first surface and a second surface opposite
to the first surface, said gasket being squeezed into a perforation hole that perforates
the first and second surfaces, and fixed onto the housing, said gasket comprising:
a lid part that contacts the first surface and serves as a flat spring; and
an insertion part that is to be inserted into the perforation hole in the housing,
and includes an engagement part, coupled with the support part, which at least
partially projects from the perforation hole in the housing and contacts the second
surface,
wherein the engagement part includes:
a leg coupled with the support part; and
a foot that is coupled with the leg and forms an acute angle relative to the
leg.
6. A gasket according to claim 5, wherein the foot has a tip that is to contact
the second surface.
7. A gasket according to claim 5, wherein the engagement part has a projection
that prevents said gasket from coming off and projects from the foot.
8. A gasket according to claim 5, wherein the foot has a tip that can contact
the second surface, and has an acute shape in sectional that prevents coming off
of said gasket.
9. A gasket according to claim 5, wherein the engagement part has an anchor shape.
10. A gasket that serves to shield electromagnetic waves from an electronic apparatus
that has a housing that includes a first surface and a second surface opposite
to the first surface, said gasket being squeezed into a perforation hole that perforates
the first and second surfaces, and fixed onto the housing, said gasket comprising:
a lid part that contacts the first surface and serves as a flat spring; and
an insertion part that is to be inserted into the perforation hole in the housing,
and includes an engagement part, coupled with the support part, which at least
partially projects from the perforation hole in the housing and contacts the second
surface,
wherein the engagement part includes a pair of projections that extend in opposite
directions, which do not contact each other while said gasket is being inserted
into the housing, and contact each other when said gasket is being pulled off from
the housing.
11. An electronic apparatus comprising:
a housing that includes a first surface and a second surface opposite to the
first surface, the housing has a perforation hole that perforates the first and
second surfaces; and
a gasket, squeezed into and fixed onto the housing, which serves to shield electromagnetic
waves from the electronic apparatus,
wherein said gasket includes:
a lid part that contacts the first surface and serves as a flat spring; and
an insertion part that is to be inserted into the perforation hole in the housing,
wherein the insertion part includes:
a support part that extends from an approximate center of said lid part and is
accommodated into the perforation hole; and
an engagement part, coupled with the support part, which at least partially projects
from the perforation hole in the housing and contacts the second surface,
wherein the engagement part includes:
a leg coupled with the support part; and
a foot that is coupled with the leg and forms an acute angle relative to the
leg.
12. An electronic apparatus comprising:
a housing that includes a first surface and a second surface opposite to the
first surface, the housing has a perforation hole that perforates the first and
second surfaces; and
a gasket, squeezed into and fixed onto the housing, which serves to shield electromagnetic
waves from the electronic apparatus,
wherein said gasket includes:
a lid part that contacts the first surface and serves as a flat spring; and
an insertion part that is to be inserted into the perforation hole in the housing,
and includes an engagement part coupled with the support part, which at least partially
projects from the perforation hole in the housing and contacts the second surface,
wherein the engagement part includes:
a leg coupled with the support part; and
a foot that is coupled with the leg and forms an acute angle relative to the
leg.
13. An electronic apparatus comprising:
a housing that includes a first surface and a second surface opposite to the
first surface, the housing has a perforation hole that perforates the first and
second surfaces; and
a gasket, squeezed into and fixed onto the housing, which serves to shield electromagnetic
waves from the electronic apparatus,
wherein said gasket includes:
a lid part that contacts the first surface and serves as a flat spring; and
an insertion part that is to be inserted into the perforation hole in the housing,
and includes an engagement part, coupled with the support part, which at least
partially projects from the perforation hole in the housing and contacts the second
surface,
wherein the engagement part includes a pair of projections that extend in opposite
directions, which do not contact each other while said gasket is being inserted
into the housing, and contact each other while said gasket is being pulled off
from the housing.
Description
This application claims a benefit of priority based on Japanese patent application
No. 2002-367762, filed on Dec. 19, 2002, which is hereby incorporated by reference
herein in its entirety as if fully set forth herein.
BACKGROUND OF THE INVENTION
Along with recent widespread electronic apparatuses, the supply high-performance
electronic apparatuses have been increasingly demanded. For example, conventional
computers and communication controllers as exemplary electronic apparatuses have
used gaskets that can be mounted onto a housing for resistance to electromagnetic
waves from a printed plate (as disclosed, for example, in Japanese Patent Publication
No. 8-274485). This gasket is required to have a physical structure to shield electromagnetic
waves as well as a mechanical structure that facilitates mounting onto an electronic
apparatus housing and prevents falling off from the housing.
A description will be given of a conventional gasket 10 with reference to
FIGS. 20 and 21. Here, FIG. 20 is a perspective overview of the conventional gasket
10. As illustrated, the gasket includes a lid part 20 and an insertion
part 30. Due to the lid part 20 and insertion part 30, the
gasket 10 forms an approximately π shaped section. The insertion part
30 is a portion to be inserted into a housing, and includes a pair of support
parts 32 each having an approximately rectangular parallelepiped shape,
and a pair of engagement parts 34 each having an approximately right triangle
pole shape.
FIG. 21 is a sectional view before and after the gasket 10 is inserted
into a computer housing 2. The housing 2 has a perforation hole 4.
Each support part 32 is slightly longer than the perforation hole 4
in the housing 2. The gasket 10 is made of an elastic member, and
thus a pair of support parts 32 and engagement parts 34 deform so
that they approach to each other while the gasket 10 is being inserted into
the housing 2, and return so that they separate from each other after the
engagement parts 34 project from the perforation hole 4.
As shown in FIG. 21, when the gasket 10 is inserted into the housing 2,
the lid part 20 contacts a top surface 6 of the housing 2,
the support parts 32 of the insertion part 30 are located in the
perforation hole 4, and the engagement parts 34 project from a bottom
surface 8 of the housing 2, so that bracket parts 35 contact
the peripheral of the perforation hole 4. When the engagement parts 34
contact the bottom surface 8, the lid part 20 applies an elastic
force as a flat spring to the housing 2.
Thus, the conventional gasket 10 is configured so that once it is inserted
into the housing 2, the bracket parts 35 of the engagement parts
34 are hooked on the bottom surface of the housing 2 even when it
is attempted to be pulled out and it does not come off easily.
FIG. 22 is a graph of exemplary reactions in mounting the gasket 10 onto
and pulling off the gasket 10 from the housing 2. FIG. 22 shows results
of two experiments F1RF2 and F2RF2. As illustrated, it is understood that the mounting
reaction is 360 g (180 g ×2) per width, and the puling-off reaction is 140
g (70 g ×2) per width. This means that the pulling-off force is smaller than
the mounting force and the gasket 10 is easily pulled off. In other words,
the conventional gasket 10 has not had such a structure as meets a mechanical
requirement of easy mounting and hard pulling off. When the gasket 10 comes
off electromagnetic waves and noises leak from a printed circuit board in an electromatic
apparatus, undesirably causing, for example, a t levision around the electronic
apparatus to distort screen images. In addition, the coming-off gasket 10
also causes a problem of a loss due to its small size. Therefore, it is preferable
that the pulling force is larger than the mounting force and the mounting force
is as small as possible.
BRIEF SUMMARY OF THE INVENTION
Accordingly, it is an exemplary object of the present invention to provide
a gasket that is structurally easily mounted onto and hard to come off from an
electronic apparatus, and the electronic apparatus having the gasket.
In order to achieve these and other objects, a gasket of one aspect according
to the present invention that serves to shield electromagnetic waves from an electronic
apparatus that has a housing that includes a first surface and a second surface
opposite to the first surface, the gasket being squeezed into a perforation hole
that perforates the first and second surfaces, and fixed onto the housing includes
a lid part that contacts the first surface and serves as a flat spring, and an
insertion part that is to be inserted into the perforation hole in the housing,
wherein the insertion part includes a support part that extends from an approximate
center of the lid part and is accommodated into the perforation hole, and an engagement
part, coupled with the support part, which at least partially projects from the
perforation hole in the housing and contacts the second surface, wherein the engagement
part includes a leg coupled with the support part, and a foot that is coupled with
the leg and forms an acute angle relative to the leg. A gasket as another aspect
according to the present invention that serves to shield electromagnetic waves
from an electronic apparatus that has a housing that includes a first surface and
a second surface opposite to the first surface, the gasket being squeezed into
a perforation hole that perforates the first and second surfaces, and fixed onto
the housing includes a lid part that contacts the first surface and serves as a
flat spring, and an insertion part that is to be inserted into the perforation
hole in the housing, and includes an engagement part, coupled with the support
part, which at least partially projects from the perforation hole in the housing
and contacts the second surface, wherein the engagement part includes a leg coupled
with the support part, and a foot that is coupled with the leg and forms an acute
angle relative to the leg.
The foot may have a tip that is to contact the second surface. The leg may diverge
from an approximate center of the support part. The engagement part may have a
projection that prevents the gasket from coming off and projects from the foot.
The foot may have a tip that can contact the second surface, and has an acute shape
in sectional that prevents coming off of the gasket. The support part may have
a projection opposite to the perforation hole. The engagement part may have an
anchor shape. The leg may extend from the support part and forms an acute angle
relative to the support part.
A gasket as another aspect according to the present invention that serves to
shield
electromagnetic waves from an electronic apparatus that has a housing that includes
a first surface and a second surface opposite to the first surface, the gasket
being squeezed into a perforation hole that perforates the first and second surfaces,
and fixed onto the housing includes a lid part that contacts the first surface
and serves as a flat spring, and an insertion part that is to be inserted into
the perforation hole in the housing, and includes an engagement part, coupled with
the support part, which at least partially projects from the perforation hole in
the housing and contacts the second surface, wherein the engagement part includes
a pair of projections that extend in opposite directions, which do not contact
each other while the gasket is being inserted into the housing, and contact each
other while the gasket is being pulled off from the housing.
The instant inventors have experimentally confirmed that a gasket having any
one of the above structures is easily mounted onto and hard to come off from an
electronic apparatus. An electronic apparatus having any one of thes gask ts constitute
one aspect of the present invention.
Other objects and further features of the present invention will become readily
apparent from the following description of the embodiments with reference to accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
This patent application file contains a series of drawings executed in color.
Copies of this patent or patent application publication with color drawings will
be provided by the Office upon request and payment of the necessary fee.
FIG. 1 is a perspective overview showing a gasket body as one embodiment according
to the present invention.
FIG. 2 is a sectional view before and after the gasket body shown in FIG. 1
is inserted into a housing of an electronic apparatus.
FIG. 3 is a graph showing reactions in mounting the gasket body shown in FIG.
1 onto and pulling off the same from the housing of the electronic apparatus.
FIG. 4 is a partial sectional view showing a variation of a projection of a
support part in the gasket body shown in FIG. 1.
FIG. 5 is a partial sectional view showing a variation of an engagement part
of the gasket body shown in FIG. 1.
FIG. 6 is a partial sectional view showing a variation of the gasket body shown
in FIG. 1.
FIG. 7 is sectional views before and after the gasket body shown in FIG. 6 is
inserted into the housing of an electronic apparatus.
FIG. 8 is a partial sectional view showing a variation of a projection of a
support part in the gasket body shown in FIG. 6.
FIG. 9 is a perspective overview of a gasket as one embodiment according to
the present invention that has the gasket body shown in FIG. 1.
FIG. 10 is a partial sectional view showing another variation of the gasket
body shown in FIG. 1.
FIG. 11 is a perspective overview of a network device as one example of an inventive
electronic apparatus.
FIG. 12 is a view showing a plug in unit structure; that is removably accommodated
into the electronic apparatus shown in FIG. 11.
FIG. 13 is a perspective overview showing the plug in unit shown in FIG. 12
that is being removed from the network device shown in FIG. 11.
FIG. 14 is an enlarged perspective view of part A shown in FIG. 13.
FIG. 15 is a view for explaining a shield structure of the network device shown
in FIG. 11.
FIG. 16 is a perspective overview of an improvement of a conventional gasket.
FIG. 17 is a perspective overview of an improvement of the conventional gasket.
FIG. 18 is a perspective overview of another improvement of the conventional gasket.
FIG. 19 is a perspective overview of another improvement of the conventional gasket.
FIG. 20 is a perspective overview of the conventional gasket.
FIG. 21 is a sectional view before and after the gasket shown in FIG. 20 is
inserted into a computer housing.
FIG. 22 is a graph showing exemplary reactions in mounting the gasket shown
in FIG. 20 onto and pulling off the gasket from the housing.
DETAILED DESCRIPTION OF THE INVENTION
The instant inventors have conducted simulations about mounting and pulling-off
forces while partially improving a structure of the conventional gasket
10.
A description will now be given of modified structures and their effects.
The instant inventors initially reviewed an increase of a pulling-off force by
enlarging rigidity of the insertion part
30. Accordingly, a gasket
10A
shown in FIG. 16 is produced which fills between the pair of support parts
32
to form a single member, and its reaction was simulated. The gasket
10A
shown in FIG. 16 is similar to the gasket
10A. When the gasket
10A
is inserted into the perforation hole
4, the bracket parts
35 of
the engagement part
34 crush due to plastic deformation, but mounting and
pulling-off reactions increase.
Next, the instant inventors have reviewed an extension of a length of the bracket
part
35 of each engagement part
34 shown in FIG. 20 in order to increase
the contact area with the bottom surface
8 and enhance consequently the
puling-out force. Since the mounting reaction increases when the bracket part
35
extends in a direction perpendicular to the support part
32 as shown in
FIG. 20, a gasket
10B was prepared and its reaction was simulated. The gasket
10B includes a pair of engagement parts
34A each having a bracket
part
35A that extends and forms an acute angle relative to the support part
32. The gasket
10B shown in FIG. 17 is similar to the gasket
10
except that it has the bracket parts
35A. Here, FIG. 17 is a perspective
overview of the gasket
10B. It was found that when the gasket
10B
was inserted into the perforation hole
4, the bracket parts
35A of
the engagement parts
34A sufficiently deformed, thereby decreasing the mounting
reaction and increasing the pulling-off reaction.
Next, the instant inventors have reviewed a pulling-off prevention by a pair
of engagement parts
34 that approach to each other mounted onto the housing
2. Accordingly, a gasket
10C was prepared and its reaction was simulated.
The gasket
10C includes the engagement parts
34 shown in FIG. 20
that have projections
36 inside the engagement parts
34. The gasket
10C shown in FIG. 18 is similar to the gasket
10 except that it has
the projections
36. Here, FIG. 18 is a perspective overview of the gasket
10C. It was found that when the gasket
10C was inserted into the
perforation hole
4, the projections
36 of the engagement parts
34
crushed due to plastic deformation, but increased the inserting and pulling-off reactions.
Next, the instant inventors have conducted a simulation by providing the support
parts
32 shown in FIG. 20 with projections
33 opposite to the perforation
hole
4. A gasket
10D shown in FIG. 19 is similar to the gasket
10
except that it has the projections
33. Here, FIG. 19 is a perspective overview
of the gasket
10D. It was found that the gasket
10D showed the decreased
mounting reaction and the increased pulling-off reaction.
A description will be given of a gasket
100 as one embodiment according
to the present invention with reference to the accompanying drawings. The gasket
100 has been prepared considering the results of the above simulations.
Here, FIG. 1 is a perspective overview showing a gasket body
101. FIG. 2
is a sectional view before and after the gasket body
101 is inserted into
the computer housing
2. In the following description, reference numerals
with capitals are variations of members assigned reference numerals without alphabets,
and generalized by reference numerals without alphabets unless otherwise specified.
The gasket
100 includes, as shown in FIG. 9, a gasket body
101
made of an elastic material, such as silicon rubber, a cotton
190 that has
an approximately semicircle section and covers the gasket body
101, and
(electrically) conductive cloth
192. The conductive cloth
192 serves
to shield electromagnetic waves, and the cotton
190 provides the conductive
cloth
192 with elasticity and prevents damages of the conductive cloth
192.
Since the cotton
190 and conductive cloth
192 may apply any material,
manufacture and attachment known in the art of the gasket, a detailed description
thereof will be omitted.
The gasket body
101 includes, as shown in FIG. 1, a lid part
110
and an insertion part
120, and is made of an elastic material, such as silicon
rubber, similar to the gasket
20. The basket body
101 forms an approximately
π shape due to the lid part
110 and the insertion part
120.
The lid part
110 contacts the surface
6 of the housing
2
and serves as a flat spring. The lid part
110 has an approximately V-shaped
section that extends in a direction M in FIG. 1, and contacts the surface
6
of the housing
2 through a pair of ends
112. The ends
112
are chamfered or formed like a curve, and the shape differs from the nodule lid
part
20. However, the lid part
110 has substantially the same function
as the lid part
20. Therefore, the ends
112 of the lid part
110
may have a shape similar to or different from the lid part
20. The elastic
force of the flat spring is adjustable by adjusting a distance L between a tip
of the center part of the lid part
110 and part of the end
112 that
contacts the surface
6. Due to the flat spring function, the lid part
110
is deformable when the center edge line
114 is pressed after inserted into
the housing
2. The cotton
190 and the conductive cloth
192
are attached to the top surface of the lid part
110.
The insertion part
120 is a portion that is inserted into the perforation
hole
4 in the housing
2, as shown in FIGS. 1 and 2, and includes
a support part
130 and a pair of engagement parts
140.
The support part
130 extends from an approximate center of the lid part
110 and is accommodated in the perforation hole
4. The support part
130 includes a base
132, and a pair of projections
134, provided
on the base
132, which face the perforation hole
4.
The support part
130 of the instant embodiment is a single member, different
from the pair of support parts
32 of the gasket
10 shown in FIG.
20. In other words, it has the base
132 that has an approximately
rectangular parallelepiped shape that fills the inside space in the pair of support
parts
32. This is because the pulling-off reaction increases from the simulation
result of the gasket
10A shown in FIG. 16. A width W
1 of the
base
132 of the instant embodiment is set, for example, 40% to 60% of the
width W of the perforation hole
4.
A pair of projections
134 project from the support parts
130 toward
an inner surface of the perforation hole
4, contact the inner surface of
the perforation hole
4 when the gasket
100 is pulled off, increasing
the resistance and pulling-off reaction. The projection
134 is set, for
example, to be about 20% to 30% of the width of the perforation hole in the instant
embodiment. The width W
1 of the base
132 may be increased instead
of providing the base
132 with projections
134, although the width
W must be increased within a range that does not cause the plastic deformation
of the engagement part
140.
Each projection
134 of the instant embodiment exemplarily has an approximately
semicircular shape. However, they may extend in an upper oblique direction in order
to increase the reaction in pulling off the gasket
100. The number of projections
134 is not limited to one. FIG. 4 shows an enlarged side view of two projections
134A at one side of two pairs of projections
134A that extend from
the base
132 in upper oblique directions. The upper and lower projections
134A may have different shapes and lengths. The upper oblique extension
enables the projections
134A to deform while assisting in an insertion,
and apply resistance to the inner surface of th perforation hole
4 so as
to prevent pulling off. A tip of the projections
134A may be enlarged in
order to enhance the resistance with the inner surface of the perforation hole
4 at the time of pulling off.
The engagement parts
140 diverge like an approximately V shape from an
approximate center of the support part
130. They partially project from
the perforation hole
4 in the housing
2 and contact the bottom surface
8 of the housing
2, as shown in FIG.
2.
Each of a pair of engagement parts
140 includes a leg
141 coupled
with the base
132 of the support part
130, and a foot
142
arranged to form an acute angle relative to the leg
141.
In the instant embodiment, the leg
141 diverges into two from an approximate
center of the base
132 of the support part
130 and has a divergence
angle θ
2 of an acute angle. As will be described with reference
to FIG. 10, the present invention does not require the leg
141 from diverging
from the support part
130 or the angle θ
2 from the support
part
130 to be an acute angle. The leg
141 is elastically deformable
and serves to support the foot
142. The length if the leg
141 is
set to be a length connectible to the bottom surface
8.
The foot
142 is arranged so that an angle θ
1 is acute
relative to the leg
141. This is because the simulation shown in FIG. 20
by the instant inventors shows that the engagement parts
140 easily plastically
deform when they extend from the support part
32 perpendicularly, and the
reaction in pulling off the gasket decreases when the angle θ
1
is an obtuse angle. The foot
142 has a connection part
144a coupled
with the leg
144a, and a tip
144b.
In the instant embodiment, the connection part
144a is a heel of
the foot
142, but the present invention allows the leg
141 to be
connected to the foot
142 at its center.
The tip
144b contacts the bottom surface
8 of the housing
2. The tips
144b must be located outside the projections
134,
because when they are located inside the projections
134, they do not contact
the inner surface of hole
4 or the bottom surface
8 and cannot serve
as an engagement function.
When the tip
144b changes its shape from a circular section to
an acute section, as shown in FIG. 5, the tip
144b preferably deforms
so as to assist an insertion and applies the resistance to the bottom surface
8
so as to prevent pulling off. Here, FIG. 5 is an enlarged sectional view of a foot
as a variation of the foot
142 shown in FIG.
1. If necessary, the
resistance may be increased by roughing a surface of the cut end
145 and/or
applying a sticky material. The cut end
145 must face the bottom surface
8, because the cut end
145 if facing opposite to the bottom surface
8 would cause increased reaction in mounting the gasket.
FIG. 2 is a sectional view before and after the gasket
100 is inserted
into a computer housing
2. The engagement parts
140 have such a length
that when the gasket
100 is inserted into the housing
2, the tip
144b of the engagement part
140 is located near a boundary
between the perforation hole
4 and the inner surface
8.
In inserting the gasket
100 into the housing
2, a user sets the
gasket
100 on the perforation hole
4, and squeezes it by pressing
the lid part
110. If necessary, a pair of feet
142 are made narrower
by a thumb and a forefinger in squeezing the gasket
100. Since the gasket
100 is made of an elastic member, the feet
142 bend after contacting
the perforation hole
4, and deforms so that the pair of engagement parts
140 approach to each other, allowing the gasket
100 to be squeezed.
After the gasket
100 is inserted into the housing
2, the engagement
parts
140 project from the perforation hole
4, and then return so
as to be apart from each other. As shown in FIG. 2, the ends
112 of the
lid part
110 contact the top surface
6 of the housing, the support
part
130 of the insertion part
120 is located in the perforation
hole
4, and the engagement part
140 is located so that the tips
144b
are located near the boundary between the bottom surface
8 and the perforation
hole
4. The lid part
110 may apply the elastic force as a flat spring
to the housing
2 when the engagement part
140 contacts the bottom
surface
8.
Thus, after the gasket
200 is inserted into the housing
2, the
tips
144b of the feet
142 of the engagement part
140
are caught by the bottom surface
8 and the perforation hole
4 of
the housing
2, whereby the gasket
100 does not structurally easily
fall off from the housing
2 once it is mounted onto the housing
2.
FIG. 3 is a graph showing reactions in mounting the gasket body
101 onto
and pulling off the same from the housing
2, showing a result of two experiments
(F1RF2
—900001 and F1RF2
—90002). As illustrated,
the mounting reaction was 320 g (160 g×2) per width, and the pulling-off reaction
was 400 g (200 g×2) per width.
In comparison with a result shown in FIG. 22, it is understood that the pulling-off
force is greater than the mounting force, preventing easy coming off. In addition,
the mounting force decreases from 360 g to 320 g while the pulling-off force increases
from 140 g to 400 g. Therefore the gasket
100 is more easily mounted than
the gasket
10 and enhances the coming-off prevention function. Thus, the
gasket
100 meets the mechanical requirement of easy mounting an hard coming-off
more satisfactorily than the conventional.
FIG. 6 shows a gasket
101A as a variation of the gasket body
101.
The basket body
101A has the engagement part
140A different from
the engagement part
140, which includes projections
148 that face
each other at a heel of each foot
142A.
Each projection
148 prevents the gasket body
101A from being pulled
off as described with reference to FIG. 7, and protrudes from each foot
142A.
FIG. 7A is a sectional view showing a state of the projection
148 before
and after the gasket
100A is inserted into the housing
2. As illustrated,
when the gasket body
101A is being inserted into the housing
2, pair
of feet
142 bend toward the inside after contacting the perforation hole
4, and consequently deform so that heels separate from each other. Therefore,
the projections
148 provided at the heels of the feet
142 deform
so that they separate from each other, not hindering an insertion of the gasket
100A.
On the other hand, FIG. 7B is a sectional view showing a state of the projection
when pulling off of the gasket body
101A starts and ends. The instant inventors
have found that when the gasket
100A is inserted into the housing
2,
the feet
142 do not open perfectly outside the perforation hole
4
in most cases, as shown in FIG. 7A, but the tips
144b are located
near the boundary between the bottom surface
8 and the inner surface of
the perforation hole
4. In addition, the instant inventors have found that
when the gasket
100A i pulled off in that state, the tips
144b
moves up while slipping along the inner surface of the perforation hole
4.
Therefore, in an attempt to pull off the gasket
100A from the housing
when there are projections
148, as shown in FIG. 7B, the tips
144b
are caught by the inner surface of the perforation hole
4 and deform
to the outside, whereby the heels deform and approach to each other consequently.
Therefore, the projections
148 provided at the heels of the feet
142
deform, approach to each other and contact finally. When the gasket
100A
continues to be pulled off, the pulling-off force resists the elastic force after
the projections
148 contact and the force necessary for the plastic deformation
depending upon a size of the projection
148. Therefore, the projection
148
may increase the pulling-off force. According to the simulation by the instant
inventors, the pulling-off force was about 800 g, an about sextuple increase.
The present invention do not limit a size and a shape of the projection
148,
but the size and shape are preferably determined so that the projections
148
contact when the gasket body
101 is pulled off, because if the projections
148 do not contact each other when the gasket body
101A is pulled
off, they do not contribute to an increase of the pulling-off force. However, it
is optional whether the projections
140 plastically deform because the excessively
large pulling-off force with a demand for exchange of a deteriorated gasket would
make it difficult to exchange the gasket.
It is sufficient that the projections
148 act to prevent pulling off of
the gasket
100, and the present invention covers the number of projections
148 of one and three or more.
FIGS. 8A to
8C show an example that provides the gasket body
101A
with the cut ends
145, similar to FIG.
5. FIG. 8A is a partial section
showing the cut end
145 and the projection
148 before the gasket
body
101A is inserted into the housing
2. FIG. 8B is a partial section
showing the cut end
145 and the projection
148 before and after the
gasket body
101A is inserted into the housing
2. FIG. 8C is a sectional
view showing the cut end
145 and the projection
148 when pulling
off of the gasket body
101A from the housing
2 starts and ends.
As shown in FIG. 8B, the cut end
145 and the projection
148 do
not
prevent an insertion of the gasket, and the out end
145 is located near
the boundary between the perforation hole
4 and the bottom surface
8.
In addition, the cut end
145 slightly opens to the outside. As shown in
FIG. 8C, the cut end
145 is caught by the bottom surface
8 when the
gasket is pulled off, making pulling off difficult.
FIG. 10 shows a gasket body
101B as another variation of the gasket body
101. The gasket body
101B has an engagement part
140B that
is different in that it includes feet
142B with an anchor shape.
More specifically, the engagement part
140B includes legs
141B
coupled with the support part
132, and legs
142B coupled with the
legs
141B. The legs
141B of the instant embodiment is formed as a
single member without diverging from the support part
130. Similar to FIG.
1, the length of the leg
141B must be set so that the foot
142B is
connectable to the bottom surface
8. A width of the leg
141B is set
so that it provides the foot
142B with rigidity to some extent so as to
prevent the foot
142B from easily deforming in pulling off.
The tips
144b of the feet
142B must be located outside the
projections
134, similar to FIG.
1. An angle θ
3,
at which the foot
142B extends, corresponds functionally to the angle θ
2
shown in FIG. 1, and a description will be omitted. The foot
142B shown
in FIG. 10 has an arc shape having a central angle of 120°, but may have a
shape of an ellipse, quadratic curve, and other curves, a V-shape, and other shapes.
A description will now be given of a network device
200 as an inventive
electronic apparatus with reference to FIGS. 11 to
15. Here, FIG. 11 is
perspective overview of the network device
200. FIG. 12 is a view showing
a plug in unit ("PIU") structure
210. FIG. 13 is a perspective overview
showing the PIU
210 that is being removed from the network device
200.
As shown in FIG. 11, the network device
200 is a rack- or shelf-shaped
communication controller that removably accommodates plural PIUs
210 of
the same type or different types. In the instant embodiment, the network device
200 can accommodate seven PIUs
210, but the number is exemplary.
FIG. 11 assigns the same reference numeral to different types of PIUs for convenience.
FIG. 12 is a view showing a certain type of PIU
210 that has a LAN connector
220. FIG. 12A is a bottom view of an eject mechanism
240 of the PIU
210. FIG. 12B is a front view of the PIU
210. FIG. 12C is a plane
view of the PIU
210. FIG. 12D is a side view of FIG.
12C.
The PIU
210 shown in FIG. 12 accommodates a printed circuit board (not
shown) in a housing
212, and includes various connectors
220 to
224,
a guide module
230, and an eject mechanism
240, and a shield gasket
250.
The connector
220 is a LAN connector connected to an external terminal,
and there are plural connectors in the PIU shown in FIG.
12. Each LAN connector
220 is connected to a communication terminal that communicates on the network,
such as a personal computer ("PC") and a hub, for example, via a UTP cable (not
shown). The connector
222 is a connector connected to the network device
200. The connector
224 serves as a connector for power supply. The
guide module
230 serves to guide insertion and ejection of the PIU
210,
may apply any structure known in the art, and a detailed description thereof will
be omitted.
The eject mechanism
240 serves to eject the PU
210 from the network
device
200, and includes a pair of L-shaped card ejectors
242, and
tabs
242 provided onto them. A user pulls the tubs
244 in a direction
F shown in FIG. 12A using his/her thumb, and ejects the PIU
210 from the
network device
200. The eject mechanism
240 may use any structure
known in the art, and a description thereof will be omitted.
The PIU
210 further includes a shield gasket
250, as shown in FIGS.
12C and 12D. The gasket
250 is provided at both sides to shields right and
left sides of the PIU
210. The shield gasket
250 may apply to gasket
100, thereby preventing leakages of electromagnetic waves and noises from
the printed circuit board outside the PIU
210.
FIG. 13 is a perspective overview showing the PIU
210 that is being partially
removed from the network device
200. FIG. 14 is an enlarged perspective
view of part A shown in FIG.
13. As shown in FIG. 14, the network device
200 includes therein a shield gasket
270. The shield gasket
270
may apply gasket
100, thereby preventing leakages of electromagnetic waves
and noises from the printed circuit board (not shown) outside the network device
200.
FIG. 15A is a front view of the three-layer PIU
210 accommodated in the
network device
200 shown in FIG.
11. FIG. 15B is a side view of part
260 that contains the gasket
270 shown in FIG. 13 at the side of
the PIU
10. FIG. 15C is a view showing part of the upper PIU
210
in a view corresponding to FIG. 12A, which contacts the gasket
250 of the
lower PIU
210, and bevel part S
3 indicates a contact portion.
A contact between a spring of the connector
220 and a front-plate square
hole shield the connector
220 as shown in an arrow S
1 in FIG.
15A, nd a contact with a gasket of the next PIU
210 maintains an electromagnetic
shield. As discussed above, the cotton
190 is so elastic that the gasket
does not get damaged even when the upper PIU
210 contacts or moves on the
conductive cloth
192.
According to the network device
200 that utilizes the inventive
gaskets
250 and
270, electronic waves generated from the network
device
200 and the PIU
210 can be prevented from leaking.
Further, the present invention is not limited to these preferred embodiments,
and various variations and modifications may be made without departing from the
spirit and scope thereof. For example, an electronic apparatus applicable to the
present invention is not limited to network devices.
Thus, the present invention may provide a gasket that is structurally easily
mounted onto and hard to come off from an electron apparatus, and the electronic
apparatus having the gasket.
*
