JPH057442Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to a camshaft shaft mounting device for a four-stroke engine.

[Conventional technology and its problems]

In a four-stroke engine, a camshaft is mounted on the cylinder head and rotated in conjunction with the crankshaft using a chain, and the rotation of the camshaft's cam pushes a rocker arm to open and close umbrella-shaped intake and exhaust valves. In general, the camshaft is mounted on a plurality of lower bearings provided on the upper surface of a cylinder head, and an upper bearing is aligned with each lower bearing and tightened to support the camshaft.
The upper bearing must be highly rigid and durable. If the upper bearing is integrally provided with the head cover that is attached to the cylinder head, it can have high rigidity, but since the tightened state cannot be visually observed, there is an inconvenience that it is difficult to detect incorrect assembly such as the falling off of the rocker arm.

[Purpose of invention]

This idea involves aligning the camshaft with a plurality of lower bearings on the top surface of the cylinder head, temporarily holding it down with a temporary holding piece, visually confirming the assembly of the rocker arm, etc., and then attaching the head cover. To obtain a camshaft shaft mounting device for a four-stroke engine, which allows confirming the normal assembly state by aligning and tightening a plurality of upper bearing parts integrally provided on a head cover with a lower bearing part.

[Structure of the idea]

The camshaft shaft mounting device for a four-cycle engine of the present invention includes a lower bearing part provided on the upper surface of the cylinder head, a camshaft fitted to the lower bearing part, and a camshaft shaft which is latched and fastened to the cylinder head to temporarily hold the camshaft. The camshaft is equipped with a temporary holding piece for holding the cylinder head, and a head cover which is attached to the cylinder head and is integrally provided with an upper bearing part, and the camshaft is mounted on the shaft with the upper bearing part aligned with the lower bearing part. .

〔Example〕

The present invention will be explained below with reference to embodiments shown in the drawings.

The cylinder head 1 has vertical walls 2 at predetermined intervals.
are integrally provided, and a lower bearing portion 3 having a semicircular cross section is provided on the upper surface of this standing wall 2. After assembling the valve 4, lash adjuster 5, and rocker arm 6 to the cylinder head 1, the camshaft 7 is fitted to the lower bearing part 3. The temporary holding piece 8 is
A hooking part 9 is provided on the upper part, and the hooking part 9 is hooked to the camshaft 7, and the temporary holding piece 8 is tightened to the cylinder head 1 with a bolt 10, and the camshaft 7 is fixed.
Temporarily hold it on the lower bearing part 3. Head cover 11
A vertical wall 12 is formed integrally with the vertical wall 2 of the cylinder head 1, and an upper bearing portion 13 having a semicircular cross section is provided on the lower surface of the vertical wall 12. The head cover 11 is attached to the upper surface of the cylinder head 1, the upper bearing part 13 is aligned with the lower bearing part 3, the camshaft 7 is mounted on the shaft, and the head cover 11 is fastened to the cylinder head 1 with bolts 14.

[Effect of invention]

When the camshaft 7 is aligned with the lower bearing part 3 of the cylinder head 1, it can be temporarily held down with a temporary holding piece 8 to check whether the camshaft 7 is in the correct assembly state, such as its relative position with the rocker arm 6. By putting the head cover 11 over the cylinder head 1 and tightening it, the camshaft 7 can be mounted with high rigidity by the lower bearing part 3 of the cylinder head 1 and the upper bearing part 13 of the head cover 11. thus,
It can be made without incorrect assembly.

[Effects of the invention] As explained above, this invention consists of a lower bearing part provided on the upper surface of the cylinder head, a camshaft fitted to the lower bearing part, and a camshaft which is latched onto the camshaft and fastened to the cylinder head. The camshaft is equipped with a temporary holding piece for temporarily holding the cylinder head, and a head cover which is attached to the cylinder head and is integrally provided with an upper bearing part, and the camshaft is mounted on the shaft by aligning the upper bearing part with the lower bearing part. This makes it possible to temporarily hold the camshaft with the temporary holding piece before attaching the head cover, and to check the assembly status of each part, thereby preventing incorrect assembly. When the head cover is tightened, the camshaft can be mounted with high rigidity using the lower bearing part of the cylinder head and the upper bearing part integrated with the head cover.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, in which FIG. 1 is a vertical sectional front view, FIG. 2 is an enlarged view of the same part, and FIG. 3 is a lateral side view. 1...Cylinder head, 3...Lower bearing part,
7...Camshaft, 8...Temporary holding piece, 11...
Head cover, 13... Upper shaft bearing part.

Claims (1)

[Scope of utility model claims] A lower bearing part provided on the upper surface of the cylinder head, a camshaft fitted to the lower bearing part, a temporary holding piece that is latched to the camshaft and fastened to the cylinder head to temporarily hold the camshaft, and a temporary holding piece that is covered with the cylinder head. 1. A camshaft shaft mounting device for a four-stroke engine, comprising: a head cover which is attached to the camshaft and is integrally provided with an upper bearing portion; and a camshaft is mounted on the camshaft with the upper bearing portion aligned with the lower bearing portion.