JPH0752963Y2 - Resin member mounting structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a first member made of resin, for example, a resin rocker cover for an automobile engine, and a second member made of metal or other material, such as the above. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mounting structure in which a liquid gasket is interposed in a cylinder head of an engine and tightened and fixed by bolts while ensuring oil tightness.

(Prior Art) A typical structure in which a resin rocker cover in an automobile engine is oil-tightly attached to a metal cylinder head will be specifically described with reference to FIGS. 2 and 3. First, the second
In the figure, reference numeral 10 in the figure is a peripheral flange portion of a rocker cover made of an appropriate resin material, 12 is a metal cylinder head for fastening the flange portion 10 with bolts 14,
16 is a liquid gasket known per se interposed between the flange portion 10 and the cylinder head 12, and 18 is a hollow cylindrical metal collar integrally embedded or molded in the bolt insertion portion of the flange portion 10. Or it is a spacer. The collar or the spacer 18 is configured so that the tightening force of the bolt 14 prevents damage to the flange portion 10 in the bolt axial direction as shown in the drawing in order to avoid damage to the flange portion 10 made of resin. It is usually formed slightly higher than the thickness.

According to this configuration, when an external force in the peeling direction as shown by an arrow P in the figure acts on the rocker cover during operation of the engine,
Since the adhesion between the collar or the spacer 18 and the surrounding resin portion is low, they are relatively easily separated from each other, and a gap is created on the contact surface between the flange portion 10 and the cylinder head 12, and the liquid gasket 16 is peeled off. As a result, the oil-tightness is impaired.

Next, in the structure shown in FIG. 3, metal collars or spacers 18 that are integrally embedded or molded in the bolt insertion portions of the resin flange portion 10 similar to those in FIG. It is characterized in that it has a collar 20 extending outward in the radial direction. According to this structure, the collar or the spacer 18 is provided with the collar.
The provision of 20 prevents separation of the collar or the spacer 18 and the surrounding resin portion when an external force in the peeling direction as shown by an arrow P in the figure acts on the rocker cover. As indicated by symbol C in Fig. 5, cracks due to stress concentration easily occur near the sharp edge of the collar 20,
In the worst case, the bolt 14 and the collar or the spacer 18 are separated from the flange portion 10, and of course, the oil tightness of the liquid gasket 16 is lost.

(Problems to be Solved by the Invention) The present invention has been made in view of the above circumstances, and is a resin member that does not damage the resin member for a long period of time and does not impair the oil tightness of the liquid gasket. The purpose of the present invention is to provide a mounting structure.

(Means for Solving the Problems) In order to achieve the above object, the present invention relates to a method in which a resin-made first member is attached to a second member by a bolt, and a liquid gasket is interposed between both members. The bolt insertion part of the first member has an outer peripheral surface having a gradual curvature or a barrel shape, and has a bolt insertion hole in the central portion, and further, both end surfaces in the bolt axial direction have the first member of the first member. The present invention proposes a mounting structure for a resin member, characterized in that an insert member made of a metal material and slightly protruding from the surface is integrally embedded.

(Operation) According to the present invention, the insert member made of a metal material, which is integrally embedded or molded in the bolt insertion portion of the resin first member, has an outer peripheral surface having a gradual curvature slump or barrel shape. Since the insert member does not separate from the first member when an external force is applied to the first member in the direction of separating the second member from the first member, and the insert member and the resin portion around the insert member are loose. Since they are in contact with each other along a curved surface having a gradual curvature or a barrel shape, the occurrence of cracks due to stress concentration can be reliably prevented.

(Embodiment) An embodiment of the present invention will be specifically described below with reference to FIG. (Note that members and portions substantially the same as or corresponding to those of the conventional configuration shown in FIGS. 2 and 3 are denoted by the same reference numerals, and redundant description will be omitted.) According to the present invention, Resin rocker cover, that is, the flange portion 10 of the first member
A collar or spacer or insert member 18 made of a metallic material, which is integrally embedded or molded in the portion of the bolt 14 to be inserted, has a curve of a gentle curvature around the axis of the bolt 14 (for example, an arc, a parabola or other It has an outer peripheral surface consisting of a zigzag-shaped rotating surface obtained by rotating a curved line). Further, the insert member 18 has first end portions in the axial direction of the bolt 14, that is, upper and lower end surfaces in the drawing as the first
It is formed to slightly project from the adjacent surface of the member 10.

According to this configuration, when an external force P for separating the first member 10 from the second member, for example, the cylinder head 12, acts,
Since the insert member 18 is not easily separated from the surrounding resin portion, the liquid gasket 16 interposed between the first and second members does not peel off, and excellent oil tightness is ensured for a long time. be able to. Also, the insert member 18
Since the outer peripheral surface of the has a curved surface with a gentle curvature, generation of cracks due to stress concentration can be effectively prevented, and durability and reliability can be improved.

In the above embodiment, the outer peripheral surface of the insert member 18 is formed in a hook shape, but the outer diameter of the central portion in the axial direction of the bolt is large, and the outer diameter of the upper and lower end portions is small. May be. Further, the present invention is not limited to the structure in which the rocker cover in the illustrated engine is attached to the cylinder head, but can be widely applied to a structure in which various resin members are attached to other metal members by bolts.

(Effect of the Invention) As described above, the mounting structure of the resin member according to the present invention is
Attach the first resin member to the second member with a bolt,
In addition, in the one in which a liquid gasket is interposed between both members, the bolt insertion portion of the first member has a stepped shape or a barrel shape with a gentle curvature on the outer peripheral surface, and the bolt insertion hole is provided in the central portion. Further, both end surfaces in the axial direction of the bolt are integrally embedded with an insert member made of a metal material, which slightly protrudes from the surface of the first member, and the oil of the liquid gasket is extended over a long period of time by a simple structure. Since the tightness and / or the airtightness can be ensured, it is practically useful.

[Brief description of drawings]

FIG. 1 is a sectional view of an essential part showing an embodiment of the present invention, and FIGS. 2 and 3 are sectional views of an essential part similar to FIG. 1 showing a conventional resin member mounting structure. 10 …… First member (resin rocker cover flange), 12
...... Second member (cylinder head), 14 ... Bolts, 16 ...
… Liquid gasket, 18 …… Collar or spacer (insert member).

Claims (1)

[Scope of utility model registration request] 1. A first member made of resin is attached to a second member by a bolt, and a liquid gasket is interposed between the two members. A bolt insertion portion of the first member has an outer peripheral surface with a gentle curvature. An insert member made of a metal material, which is in the form of a hook or a barrel, has a through hole for the bolt in the center, and has both end faces in the axial direction of the bolt slightly protruding from the surface of the first member, is integrally embedded. Mounting structure for resin member characterized by