Cover member fastening method and fastening structure for a head cover

Abstract

Provided are a cover member fastening method and a fastening structure whereby the surface area in contact with an engine body is decreased, minimizing the transmission of vibrations to the cover member. Said fastening method and fastening structure also minimize deformation of the cover member while securely affixing abutting parts that need to be firmly fixed in place. The provided fastening structure uses a fastening member (7) to fasten a head cover (2) to a cylinder head (1) so as to cover the top surface of said cylinder head (1). Abutting parts (27) that abut against the top surface of the cylinder head (1) are formed on the inside surface of the head cover (2). The bottom surfaces of head-cover-side fastening boss parts (26) protrude farther than the bottom surface of a head-cover-side attachment flange (22). The surface area (A) of the bottom surfaces of the head-cover-side fastening boss parts (26) equals or approximates a minimum contact area (Amin) obtained by dividing the required axial fastening force (N) of the fastening member (7) by a stress tolerance (sa) determined by the material that the head cover (2) is made of.

Description

technical field [0001] The present invention relates to a fastening method of a cover member and a fastening structure of a cylinder head cover of an internal combustion engine. Background technique [0002] Conventionally, as a sealing structure of a cylinder head cover of an internal combustion engine, a sealing structure using a liquid filler and a sealing structure using a rubber gasket are known. From the viewpoint of preventing noise caused by transmission of vibration from the cylinder head to the cylinder head cover, it is preferable to employ a structure in which the head cover is floated and held by a rubber packing having a noise prevention effect better than that of a liquid filler. [0003] However, the floating structure of the rubber packing is not suitable when there is an abutting portion required for more firm abutting fixation between the cylinder head cover and the upper surface of the cylinder head. On the other hand, although the sealing structure of t...

AI Technical Summary

Problems solved by technology

[0003] However, the floating structure of the rubber gasket is not appropriate when there is an abutment portion required for more secure abutment fixation between the cylinder head cover and the upper surface of the cylinder head.

On the other hand, although the sealing structure of the liquid packing is suitable for fixing the abutting part, the sealing structure of the liquid packing is not only inferior to the rubber gasket in terms of vibration and noise prevention effect, but also for the cylinder head cover that needs to be disassembled and replaced during maintenance, such as the cylinder head cover. It is difficult to maintain a uniform sealing surface for parts that perform sealing peeling and recoating, so it is difficult to strictly control the gap between the abutting parts

Images