Stock material or miscellaneous articles – Structurally defined web or sheet – Including variation in thickness
Reexamination Certificate
2000-01-24
2004-12-28
Pyon, Harold (Department: 1772)
Stock material or miscellaneous articles
Structurally defined web or sheet
Including variation in thickness
C428S217000, C428S043000, C428S057000, C428S035200, C280S732000, C280S728300, C280S728200, C280S728100, C264S500000, C264S513000, C264S520000, C264S523000
Reexamination Certificate
active
06835439
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Technical Field of the Invention
The present invention relates to a method of producing a panel for an airbag of an automobile and the panel for the airbag of an automobile produced by the method, the panel being formed of an airbag cover (i.e., a cover body), made of a first synthetic resin, and the airbag cover or cover body being formed in a main body, the main body being made of a second, different synthetic resin, and the main body being, for example, an instrument panel or a door trim.
2. Discussion of Background
An airbag arranged in front of a front passenger seat of an automobile is stored on a rear side of the main body, the main body being, for example, an instrument panel or a door trim. When the airbag is operated, the airbag cover (i.e., cover body), mounted on the instrument panel, is opened and the airbag swells out in front of the instrument panel.
As shown in
FIG. 51
, an airbag cover
92
and an instrument panel main body
91
are formed as separate members, and the airbag cover
92
is fixed to the instrument panel main body
91
by a fixture (not shown). The airbag swells out in front of the instrument panel by rupturing a weak portion, such as a thin wall portion formed in advance in the airbag cover
92
.
However, in the panel for the airbag having the structure described above, each of the instrument panel main body
91
and the airbag cover
92
are made in separate processes. Accordingly, a certain number of producing steps are required with respect to each of the instrument panel main body
91
and the airbag cover
92
. Further, it is necessary to perform an assembly step to integrate both the members
91
and
92
with respect to each other and arrange a fixture. Accordingly, a problem exists in that the entire production cost of the airbag is increased.
This problem is similarly caused when a door trim, instead of the instrument panel, is set on a main body and the airbag cover is formed therein.
In consideration of such conventional problems, the present invention provides a panel for an airbag for an automobile which is produced easily and at a low cost, and provides a production method for the panel for the airbag of the automobile.
SUMMARY OF THE INVENTION
An embodiment of the present invention is a panel for an airbag of an automobile formed by integrally two-color molding a cover body, made of a first soft synthetic resin, with a main body, made of a second hard synthetic resin, the panel comprising:
a joint portion joined with the cover body provided around an opening portion formed in the main body,
wherein the joint portion constitutes an overlapping portion in which an outer peripheral edge of the cover body is overlapped as being arranged on the inner side of an opening edge of the main body and the overlapping portion is welded together in two-color molding the main body with the cover body.
In the present invention, the overlapping portion is arranged around the opening portion (an airbag swelling-out portion) of the main body, such as the instrument panel, in which an outer peripheral edge of the cover body (airbag cover) is overlapped as being arranged on the inner side of an opening edge of the main body. Therefore, neither a fixture, for connecting both the members, nor a connecting step, are required. Thus, in accordance with the present invention, the number of production steps and cost can be greatly reduced compared with a conventional product in which the cover body and the main body, such as the instrument panel, are separately formed.
With respect to the above-described embodiment of the present invention, it is preferable that the synthetic resin of the main body is a hard synthetic resin and the synthetic resin of the cover body is a soft one. Thereby, a rupturing operation of the cover body, which swells out of the airbag, can be smoothly performed by the soft synthetic resin, and the main body, such as the instrument panel, can maintain an excellent rigidity due to the hard synthetic resin.
As a particular means for improving joining strength of both the members in the overlapping portion, for example, it is preferable that a concavo-convex portion, having a serrated shape or a downwardly convex shape, is formed on a lower face of the main body in the overlapping portion as in an embodiment of the present invention. This constitution utilizes a so-called anchor effect yielded from a part of the synthetic resin of the cover body biting into a concave portion of the concavo-convex portion of the main body at a molding time of the cover body. The joining strength of both the members is improved by this anchor effect.
Further, distortion can be prevented at the time of molding a peripheral edge of the opening portion of the main body. Namely, when the cover body is molded, after the molding of the main body, the concavo-convex portion of the overlapping portion becomes resistance to an injection force of a material for molding the cover body. Therefore, no peripheral edge of the opening portion of the main body is distorted due to the injection force which pushes on the overlapping portion of the main body.
In each of the above two means, the joining strength of the main body and the cover body can be improved by an easy method and a simple structure.
Further, as in an embodiment of the present invention, it is preferable that a surface of a periphery of the cover body has a step portion backing to a rear surface of the cover body and facing the edge of the opening portion of the main body, thereby, a groove portion, having a closed curve shape, is formed in a boundary portion of an end portion of the opening portion of the main body in the cover body, and a thin wall portion, which ruptures, and a non-thin wall portion, which does not rupture at the operating time of the airbag, are formed along the groove portion in the cover body in a single line shape or a shape of plural continuous lines.
In this case, in a portion continuously connected to the groove portion, it is possible to easily form the thin wall portion thinner than the thicknesses of wall portions in the other portions. The thin wall portion ruptures earlier than peripheral portions when pressure is applied to this thin wall portion, and thus the thin wall portion practically becomes a rupturing portion of the cover body when the airbag is operated.
The boundary portion of the cover body and the main body can be easily observed because of the groove portion, and an excellent appearance in design may be also given depending on a shape of groove shape.
When the thin wall portion ruptures and the cover body is opened, it is preferable that the shape of a line forming the thin wall portion and the shape of a line forming the non-thin wall portion are set onto the cover body such that the non-thin wall portion becomes a rotating central axis of an opening movement of the opening portion of the cover body.
In this case, when the airbag is operated and the thin wall portion ruptures, a turning moment, with the non-thin wall portion as a rotating center, is applied to a ruptured cover portion and the cover body is easily opened. Accordingly, resistance to the airbag swelling-out is reduced and the airbag easily swells out.
For example, a combination of the shape of the line forming the thin wall portion and the shape of the line forming the non-thin wall portion, so as to set the non-thin wall portion on the rotating central axis of the opening movement of the opening portion of the cover body as mentioned above, is constructed as will be described with respect to a particular embodiment of the present invention in more detail below.
For example, as in an embodiment of the present invention, the non-thin wall portion is formed into a shape of one transverse line on an upper or lower side of the cover body, and the thin wall portion is formed in a U-shape (i.e., a quadrilateral shape with one side opened) along a groove portion in three directions except for the line forming the non-thin wall portion (see FIG.
2
). Thus, a cover portio
Fukuda Haruo
Furukawa Yusaku
Hayashi Isao
Inomata Nobuo
Kanayama Torao
Simone Catherine
Toyota Shatai Kabushiki Kaisha
LandOfFree
Panel for air bags and method of manufacturing the same does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Panel for air bags and method of manufacturing the same, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Panel for air bags and method of manufacturing the same will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3337028