Seal for a joint or juncture – Seal between fixed parts or static contact against... – Contact seal for a pipe – conduit – or cable
Reexamination Certificate
1999-03-03
2001-07-31
Mah, Chuck Y. (Department: 3626)
Seal for a joint or juncture
Seal between fixed parts or static contact against...
Contact seal for a pipe, conduit, or cable
C277S635000, C277S650000, C016S002100, C174S07700S
Reexamination Certificate
active
06267385
ABSTRACT:
This application is the national phase under 35 U.S.C. §371 of prior PCT International Application No. PCT/JP97/03094 which has an International filing date of Sep. 3, 1997 which designated the United States of America.
1. Technical Field
The present invention relates to a grommet, and more particularly to a rubber grommet fixed to a wire such as an electric wire with an adhesive tape and providing hermetical sealing between the wire passed through a through hole penetrating through a partition and an inner wall of the above-mentioned through hole.
2. Background Art
In recent years, electronic control has been employed for engine control in automotive vehicles. It has become therefore necessary that a larger number of wires such as electric wires as compared to the number of conventional ones are passed through through holes perforated through a partition dividing an engine room from a cabin to connect various instruments in the engine room to an operation panel in the cabin.
However, in stop, noise or water from entering the cabin, the cabin must be separated from the engine room and a trunk room. Also for the through holes perforated through the partition between the engine room and the cabin, it is necessary to provide hermetical sealing between the wires such as the electric wires passed through the through holes and inner walls thereof. As shown in
FIG. 1
, therefore, a grommet
10
is used which has a large diameter portion formed to be layer in diameter than the inside diameter of the through hole
22
perforated through the partition
20
between the engine room and the cabin. As shown in
FIG. 2
, this grommet
10
is formed of rubber in a hollow form, the electric wire
14
is inserted therethrough until the grommet reaches halfway of the wire, and the grommet is fixed to the electric wire
14
at both ends thereof with adhesive tapes
12
and
12
.
Such an electric wire
14
to which the grommet
10
is fixed halfway is passed through the through hole
22
in the direction indicated by the arrow A (FIG.
1
), thereby inserting the large diameter portion of the grommet
10
into the through hole
22
while being deformed. Thus, a periphery portion of the through hole
22
is received in a groove
18
adjacent to a flange
16
. Consequently, the grommet
10
can provide sealing between the wire
14
passed through the through hole
22
and an inner wall of the through hole
22
.
On the other hand, for facilitating the inserting operation of the grommet
10
when the grommet
10
is inserted into the through hole
22
, a surface of the grommet
10
is coated with soapy water or oil in some cases. This is because the frictional resistance between the grommet
10
and the inner wall of the through hole
22
can be reduced by such application of soapy water or oil.
However, the coating operation of soapy water or oil complicates the inserting operation of the wire
14
, so that a grommet
10
which can omit the coating operation of oil or the like has been desired.
DISCLOSURE OF INVENTION
Accordingly, the present inventors have tried to form a grommet, using self-lubricating rubber from which a lubricative component such as oil naturally bleeds out.
According to the grommet thus formed of the self-lubricating rubber, the operation for applying soapy water or oil can be omitted.
However, as the conventional self-lubricating rubber, one containing silicone oil or paraffin oil as the lubricative component which bleeds out has been used. However, it has become clear that the grommets from which these lubricative components bleed out can not be fixed to wires with adhesive tapes, because these lubricative components also act as release agents.
It is therefore an object of the present invention to provide a grommet formed of self-lubricating rubber and fixable to a wire such as an electric wire with an adhesive tape. As a result of studies for attaining the above-mentioned object, the present inventors have discovered that a grommet formed of self-lubricating rubber containing an oily polyalkyl carbonate as a lubricative component can be fixed to an electric wire with an adhesive tape, even if the lubricative component has bled out on a surface of the grommet, thus completing the present invention.
That is to say, the present invention provides a rubber grommet fixed to a wire such as an electric wire with an adhesive tape and providing hermetical sealing between the wire passed through a through hole penetrating through a partition and an inner wall of the above-mentioned through hole, in which the rubber forming the grommet is self-lubricating rubber containing a lubricative component which bleeds out on a surface of the grommet to allow a reduction in frictional resistance with the inner wall of the through hole, and an adhesive tape can be adhered to a surface of the above-mentioned grommet.
In the present invention, an oily polyalkyl carbonate represented by the following chemical formula is preferably used as the lubricative component.
Chemical Formula
Ri—O—CO—O—[CH
2
CH
2
C(CH
3
)HCH
2
CH
2
—O—CO—O]n—Ri
wherein n is an integer of 1 to 8, and Ri represents (i—C
7
H
15
).
Further, the addition of a copolymerized rubber of the ethylene-propylene family as a main component forming the rubber, particularly, the addition of ethylene-propylene copolymerized rubber (EPM) or ethylene-propylene-non-conjugated diene ternary copolymerized rubber (EPDM), alone or as a mixture, to the rubber in an amount of 60% by weight or more can give excellent heat resistance and resistance to ozone to the grommet.
Furthermore, the grommet having excellent heat resistance and resistance to ozone can be sufficiently fixed to the wire such as the electric wire with the adhesive tape such as a vinyl tape by adding 3 parts by weight or more of the oily polyalkyl carbonate represented by the following chemical formula to 100 parts by weight of the copolymerized rubber of the ethylene-propylene family, the main component forming the rubber.
Chemical Formula
Ri—O—CO—O—[CH
2
CH
2
C(CH
3
)HCH
2
CH
2
—O—CO—O]n—Ri
wherein n is an integer of 1 to 8, and Ri represents (i—C
7
H
15
).
According to the present invention, the rubber forming the grommet is formed of the self-lubricating rubber, and the lubricative component bleeds out on the surface of the grommet. Accordingly, the frictional resistance of the grommet with the inner wall of the through hole perforated through the partition can be reduced, and the operation for coating the surface of the grommet with soapy water or oil can be omitted.
Moreover, the lubricative component which bleeds out on the surface of the grommet does not substantially inhibit adhesive ability of an adhesive forming the adhesive tape, so that the adhesive tape can be adhered to the surface of the grommet on which the lubricative component bleeds out.
As a consequence, the grommet formed of the self-lubricating rubber containing the lubricative component which bleeds out on the surface thereof can be fixed to the wire with the adhesive tape, so that the use of the grommet of the present invention allows the sealing operation for providing hermetical sealing between the wire passed through the through hole and the inner wall thereof to be easily conducted.
REFERENCES:
patent: Re. 36293 (1999-09-01), Mizui et al.
patent: 4512930 (1985-04-01), Romano
patent: 5326486 (1994-07-01), Mizui et al.
patent: 5384056 (1995-01-01), Tanaka et al.
patent: 4-41526 (1992-09-01), None
patent: 6-256599 (1994-09-01), None
patent: 7-138586 (1995-05-01), None
patent: 7-115286 (1995-05-01), None
Aoki Katsuhiko
Okamoto Katsuo
Okazawa Masanori
Shibata Yutaka
Tsujino Hisayasu
Kabushiki Kaisha Miyasaka Gomu
Mah Chuck Y.
Peavey Enoch E
LandOfFree
Grommet does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Grommet, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Grommet will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2487290