JP2530906Y2 - Rocker shaft mounting structure - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure for mounting a rocker shaft on which a rocker arm for driving a valve of an internal combustion engine is mounted.

[0002]

2. Description of the Related Art FIG. 4 shows a vertical section of a cylinder head showing a conventional rocker shaft mounting structure, and FIG. 5 shows an exploded perspective view of the cylinder head.

As shown in FIG. 4, in the case of a DOHC type engine, a cam 10
2 are rotatably supported. Below each camshaft 103, a pair of rocker shafts 104 are mounted in parallel with the camshafts 103. A base end of a rocker arm 105 is rotatably attached to each of the rocker shafts 104, and a cam 102 of a camshaft 103 can abut on an intermediate portion.

The cylinder head 101 has a combustion chamber 1
An intake valve 107 for taking in air at 06 and an exhaust valve 108 for taking out air are movably mounted. A tip of a rocker arm 105 is connected to each upper end of the intake valve 107 and the exhaust valve 108.

When the camshaft 103 rotates, the cam 102 comes into contact with the intermediate portion of the rocker arm 105 to rotate the rocker arm 105 and drive the intake valve 107 and the exhaust valve 108.

[0006]

In the above-mentioned conventional rocker shaft mounting structure, as shown in FIG. 5, the rocker shaft 104 is inserted and mounted in an insertion groove 109 formed in the cylinder head 101. I have. At this time, a plurality of rocker arms 105 are mounted on the rocker shaft 103 one by one.
Therefore, there is a problem that not only the work is troublesome, but also the work time is long, and the workability of mounting the rocker shaft 104 and the rocker arm 105 is not good.

It is an object of the present invention to solve such a problem, and an object of the present invention is to provide a mounting structure of a rocker shaft which improves mounting workability.

[0008]

In order to achieve the above object, a rocker shaft mounting structure according to the present invention has an insertion groove formed in a cylinder head along an axial direction of a camshaft, and a rocker arm is formed in the insertion groove. And the rocker shaft is inserted, and the rocker shaft mounting bolt penetrates the rocker shaft from above and is screwed into the cylinder head, whereby the rocker shaft is fixed, and the head of the rocker shaft mounting bolt is further fixed. One of mounting bolts of a cam cap for rotatably supporting the camshaft is screwed into the portion.

[0009]

The rocker shaft is inserted into the insertion groove of the cylinder head, and the rocker shaft mounting bolt is fixed by penetrating the rocker shaft, so that the rocker arm can be mounted on the rocker shaft in advance. Mounting becomes easy.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a sectional view of a main part of a cylinder head showing a rocker shaft mounting structure according to an embodiment of the present invention, and FIGS. 2 and 3 are longitudinal sectional views of the cylinder head at different positions.

As shown in FIGS. 2 and 3, a pair of camshaft insertion grooves 12 are formed in the cylinder head 11 along the longitudinal direction (the direction perpendicular to the plane of the drawing in FIG. 2). Inside the camshaft insertion groove 12, a rocker shaft insertion groove 13 that is parallel to the camshaft insertion groove 12 is formed. The plurality of rocker arms 14 are inserted into the respective rocker shaft insertion grooves 13 from above with their base ends rotatably mounted on the rocker shaft 15. The cylinder head 11 has an intake valve 17 for taking air into the combustion chamber 16 and an exhaust valve 1 for exhausting.
The upper end of the intake valve 17 and the upper end of the exhaust valve 18 are connected to the tip of a rocker arm 14.

As shown in FIG. 1, the rocker shaft 15 has through holes 19 formed at predetermined intervals in the axial direction. The rocker shaft mounting bolt 20 has a head portion that is long in the axial direction and has a screw hole 21 formed at the center and a screw portion 22 formed at the tip. Then, the rocker shaft mounting bolt 20 is inserted into the through hole 19 of the rocker shaft 15.
Is screwed into the screw hole 23 of the cylinder head 11 so that the rocker shaft 15
Is fixed to the cylinder head 11.

A cam portion 25 is formed on the outer periphery of the camshaft 24 so as to abut against and rotate the intermediate portion of each rocker arm 14. 12 and is supported by a plurality of cam caps 26 from above. The cam cap 26 is fixed to the cylinder head 11 by two cam cap bolts 27 and 28. The cam cap bolt 27 is screwed into the cylinder head 11, while the cam cap bolt 28 is a screw hole of the rocker shaft mounting bolt 20. 21 is screwed.

The rocker shaft mounting bolt 20 and the cam cap bolt 28 have different screw sizes to prevent the rocker shaft mounting bolt 20 from loosening. For example, the screw size of the screw portion 22 of the rocker shaft mounting bolt 20 is M8, and the cam cap bolt 2
The screw size of No. 8 is M6. Accordingly, the tightening torque differs depending on the different screw size, and the rocker shaft 15 can be securely fixed by securing the tightening axial force of the rocker shaft mounting bolt 20. In FIG. 2, reference numeral 29 denotes a lubricating oil supply path,
And so on.

Thus, the rocker shaft 15 is inserted into the insertion groove 13 of the cylinder head 11, and the rocker shaft mounting bolt 20 is inserted into the through hole 19 of the rocker shaft 15.
Can be fixed by penetrating the rocker arm, so that each rocker arm 14 can be mounted on the rocker shaft 15 in advance, and the rocker shaft 15 and the rocker arm 14 can be easily attached. Rocker shaft 1
By arranging the cylinder head 5 below the cam cap 26, the width of the cylinder head 11 can be narrowed and the size can be reduced.

[0017]

As described above in detail with reference to the embodiments, according to the rocker shaft mounting structure of the present invention, the rocker shaft on which the rocker arm is mounted is inserted into the insertion groove formed in the cylinder head. Since the rocker shaft mounting bolt penetrated this rocker shaft from the top and screwed to the cylinder head, it was fixed and one of the mounting bolts of the cam cap supporting the cam shaft was screwed to the head of the rocker shaft mounting bolt. The rocker shaft can be mounted on the cylinder head in a state where the rocker arm is mounted on the rocker shaft in advance, thereby facilitating the mounting of the rocker shaft and the rocker arm, shortening the working time, and improving the mounting workability. Can be.

[Brief description of the drawings]

FIG. 1 is a sectional view of a main part of a cylinder head showing a mounting structure of a rocker shaft according to an embodiment of the present invention.

FIG. 2 is a longitudinal sectional view of a cylinder head at a cylinder center position.

FIG. 3 is a longitudinal sectional view of the cylinder head at a valve center position.

FIG. 4 is a longitudinal section of a cylinder head showing a conventional rocker shaft mounting structure.

FIG. 5 is an exploded perspective view of a cylinder head.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Cylinder head 13 Rocker arm insertion groove 14 Rocker arm 15 Rocker shaft 20 Rocker shaft mounting bolt 24 Camshaft 26 Cam cap 28 Cam cap bolt

Claims (1)

(57) [Scope of request for utility model registration] An insertion groove is formed in a cylinder head along an axial direction of a camshaft, a rocker shaft having a rocker arm mounted therein is inserted into the insertion groove, and a rocker shaft mounting bolt moves the rocker shaft from above. The rocker shaft was fixed by penetrating and screwing into the cylinder head, and one of the mounting bolts of a cam cap that rotatably supports the camshaft was screwed into the head of the rocker shaft mounting bolt. A rocker shaft mounting structure, characterized in that: