JPS5851250A - Internal-combustion engine - Google Patents

Abstract

PURPOSE:To improve operability for attaching and detaching a head cover by a method wherein the head cover, accommodating a valve moving mechanism therein, is constituted of an annular member and a dish-like member detachably put on through respective packings and the packings are provided with protruded positioning protuberances. CONSTITUTION:Cylinders 5 for a V-type four cylinders internal-combustion engine are arranged in the fore and aft directions of a vehicle into a V-shape while the valve moving mechanism M is accommodated in a mechanism chamber R formed in a cylinder head 6 common to these cylinders at the aft cylinders 52 and a head cover 7 connected to the upper surface of the head 6. In this case, the head cover 7 is divided into two pieces of an annular member 71 and a shallow dish-like member 72, and a packing 181 is fitted between the member 71 and the cylinder head 6 by fitting an upwardly facing protruded rail 19 of a packing 181 of rubber into an annular groove 20 at the lower surface of the annular member 71. A packing 182 of rubber is fitted between the members 71, 72 in the same manner, however, the packing 182 is provided with a positioning protuberances 23 near the four corners of the inner peripheral surface thereof.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an internal combustion engine, particularly an overhead camshaft internal combustion engine, in which a valve mechanism is accommodated in a mechanism chamber formed inside a cylinder head and a head cover joined to the upper surface of the cylinder head. Regarding.

When this type of internal combustion engine has an upright or V-shaped cylinder and is mounted directly below the main tube of the body frame of a motorcycle, the height of the main tube may be adjusted to lower the vehicle height. When lowered, the main tube approaches the cylinder head cover, narrowing the gap between the main tube and the head cover, and since the valve mechanism protrudes from the top of the cylinder head, it becomes difficult to attach and remove the head cover when adjusting the valve mechanism, etc. There is a problem of poor sex.

In view of the above, the present invention has a head cover configured to be vertically divided into two parts, thereby making it possible to easily attach and remove the head cover, and to correctly position the two-part type head cover. An object of the present invention is to provide the internal combustion engine.

Hereinafter, one embodiment of the present invention will be described with reference to the drawings. In FIGS. 1 to 3, 1 is a body frame of a motorcycle, and the down tube 3, lower tube 4, and pillar tube 28 at the bottom of the main tube 2 are V-shaped. A four-cylinder internal combustion engine E is supported with two first cylinders 51 located at the front and two second cylinders 5□ located at the rear. In both rear second cylinders 5□, a valve operating mechanism M is housed in a mechanism chamber R formed inside a common cylinder head 6 and a head cover 7 joined to the upper surface thereof.

The valve mechanism M includes an intake valve camshaft 8 common to each second cylinder 52. and an exhaust valve cam shirt 1-8□, a pair of camshaft holders 98 and 92 that rotatably support the camshafts 8□ and 82 in cooperation with the cylinder head 6, and each camshaft 8. ．． 82 pair of cams 10. ．． 102, each pair of rocker arms'
11. ．． 11□, and a cam sprocket 1121. which is fixed to the intermediate part of each cam shirt l-8, 8□. 122 and
It consists of a cam chain 13 that is suspended around these cam sprockets l-121 and i22, and a cam chain force bar 14 that covers the cam chain 13. Each rocker arm 11□
, 112 are each threaded with a valve gap adjustment bolt 15, and each bolt 15 is threaded with a lock nut 16 for fixing their position. Therefore, a pair of intake valves or exhaust valves are opened by one rocker arm iit, it□. 17
□ and 17□ are spark plugs attached to both second cylinders 52, respectively.

The head cover 7 has a first rubber gasket 18 on the top surface of the cylinder head 6. An annular member 71 that is removably polymerized via
and a second rubber gasket 18 on the top surface of the annular member 7□.
Shallow dish-shaped member that can be attached and detached via □ 1. Therefore, it is configured in two parts.

The first packing 18□ is formed to have a convex longitudinal section, and its protruding ridge 19 fits into an annular groove 20 formed on the lower surface of the annular member 71, so that it is inserted between the cylinder head 6 and the annular member 7. It will be worn. Further, the second packing 18□ is similarly formed in a convex shape, and its protrusion 21 is fitted into an annular groove 22 formed on the upper surface of the annular member 71 to connect the annular member 7 and the plate-shaped member 7□. Each pair of positioning protrusions 23, which are sandwiched between and protrude near the four corners of the inner circumferential surface of the second packing 182 so as to sandwich each corner, are attached to the outer surface of each cam shirt holder 91.920, which is a stationary member. The annular member 71 is brought into contact with the
positioning is performed.

The dish-shaped member 72' is mounted on each camshaft by inserting the tightening bolts 25 into each of the mount rubbers 24 cut in four places on its upper surface, and by screwing the tightening bolts 25 into each camshaft bolt 91 and 92. Boulder 91. 92. The second gasket 182 is prevented from moving toward the circumference of the head cover due to the concave-convex fitting with the annular member 71, and each positioning protrusion 2 of the second gasket 18□
3 is each camshaft holder 91. 92, the annular member 71 is correctly positioned,
It is pressed and fixed to the cylinder head 6 by a dish-shaped member 72 .

In the above configuration, when adjusting the valve gap, each tightening bolt 2
Loosen and remove 5, first remove the shallow dish-shaped member γ of the head cover 7.
, within the narrow space between it and the main tube 2, and remove it laterally. Next, the annular member 71 is lifted and removed laterally within the relatively wide space between the valve train M and the main tube 2 after the dish member 72 has been removed.

In some cases, the head cover 1 may be attached by overlapping the annular member 71 and the plate-shaped member 72 on the upper surface of the cylinder head 6 in this order.

Therefore, even if the distance between the main tube 2 and the head cover 7 is narrow and the valve train M protrudes from the upper surface of the cylinder head 6, the head cover 7 can be attached and detached very easily, so the vehicle height can be set low. becomes possible.

4th. FIG. 5 shows a modification of the joint structure between the cylinder head 6 and the head cover 7. In the case of FIG. An annular groove 26.22 is formed in which the protrusions 19, 21 of the second packing ia, ts2 are fitted, and in this case, the second
Positioning protrusions 23 similar to those described above are provided on the packing 182 in a protruding manner.

In the case of Fig. 5, the lower surface of the annular member 7□ and the dish-shaped member 72
on the bottom surface of each. 2nd patchkin i8. ．． 18.
An annular groove 20.27 is formed into which the protrusion 19.21 of the first packing 18.27 fits. Positioning protrusions 23 similar to those described above are provided in a protruding manner.

Note that the same valve operating mechanism M as described above is also housed in a mechanism chamber formed inside the cylinder head 6 and head cover 7 of the two first cylinders 51 located at the front, and the head cover 7 is inserted as necessary. is constructed in two parts as described above.

As described above, according to the present invention, in an internal combustion engine in which a valve mechanism is housed in a mechanism chamber formed inside a cylinder head and a head cover joined to the upper surface of the cylinder head, the head cover is connected to the cylinder head. It is composed of an annular member that is removably superimposed on the upper surface of the annular member through a gasket, and a dish-shaped member that is removably superimposed on the upper surface of the annular member through a gasket, and at least one of the gaskets and the annular member are formed in an uneven manner. Since the fitting is fitted and the gasket is provided with a protruding positioning protrusion that comes into contact with the stationary member of the valve mechanism, the head cover is configured to be divided into two parts in the vertical direction. Even if the gap between the head cover is narrow and the valve mechanism protrudes from the cylinder head soil surface, remove the dish-shaped member of the head cover from the narrow space, then remove the annular member, or install both members in the reverse order. This makes it easy to attach and detach the head cover.

In addition, by correctly positioning the annular member using the positioning protrusion of the gasket that engages with the annular member, it is possible to avoid the trouble of positioning these constituent members when the head cover is constructed in two parts. .

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, in which Fig. 1 is a side view of a motorcycle, Fig. 2 is a plan view of a cylinder head, and Fig. 3 is a side view of a motorcycle.
The figure is a cross-sectional view taken along line 1l-i-tH in Figure 2 with the head cover joined to the cylinder head in Figure 2, and Figures 4 and 5 are partial cross-sectional views of modified examples of the joint structure of the cylinder head and head cover, respectively. It is. M... Valve mechanism, R... Mechanism chamber, 6... Cylinder head, 7... Head cover, 7,... Annular member,
72...Dish-shaped member, 91.9□...Camshaft holder as stationary member 181 i82...Packing, 23...Positioning protrusion Patent applicant Honda Motor Co., Ltd. 10- Procedural amendment (method) January 30, 1982 Patent Application No. 148185 2, Name of the invention Internal combustion engine 3, Relationship to the case of the person making the amendment Patent applicant name (532) Honda Motor Co., Ltd. 4, Agent 〒 104 5. Date of amendment order: January 5, 1982 (Shipping date: January 26, 1980)
291- Figure 3 Figure 4 Figure 5 Figure 2

Claims (1)

[Claims] In an internal combustion engine in which a valve mechanism is housed in a mechanism chamber formed inside a cylinder head and a head cover joined to the upper surface of the cylinder head, the head cover is removably attached to the upper surface of the cylinder head via a packing. and a dish-shaped member that is removably superimposed on the upper surface of the annular member via a packing, and at least one of the packing and the annular member is fitted in a convex-concave manner, and the packing is fitted with the valve actuator. An internal combustion engine that has a protruding positioning protrusion that comes into contact with a stationary member of the mechanism.