JPS62131953A - Internal combustion engine with at least one overhead cam shaft - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an internal combustion engine with at least one overhead camshaft.

BACKGROUND OF THE INVENTION An internal combustion engine of this type is described in US Pat. No. 4,430,968. This vI! i'T Ming 111+
As stated in W., in the internal combustion engine of this scale, there is a position for fixing the bearing of the overhead camshaft or its bearing cover to the cylinder head, and a position for fixing the cylinder head to the cylinder block. It is often necessary to find a compromise between the position of the cylinder head bolts used. That is, since the above-mentioned two positions often coincide, the cylinder head is assembled in advance with #11 number or a plurality of overhead camshafts, and then the unit of the cylinder head and overhead camshaft is placed over the cylinder head. I can't get it out with the screws. Rather, the cylinder head must first be screwed onto the cylinder block and then the overhead camshaft must be assembled onto the cylinder head. In this case, the cylinder head bolts cannot be retightened unless the overhead camshaft has been disassembled. In order to avoid such drawbacks, in the above-mentioned known patent 11111, a T1 through hole is provided at the optimum position for the cylinder head bolt, and this T1 through hole passes through the bearing cover and the overhead camshaft to the cylinder head. connected to the larger diameter perforation. This makes it possible to assemble the cylinder head and the overhead camshaft in advance, and to screw the cylinder head and overhead camshaft unit to the cylinder block.

Another method of screwing a preassembled unit from a cylinder head and an overhead camshaft onto a cylinder block is known from EP 0 098 180. In this patent, an opening is provided in the bearing cover between the overhead camshaft and the bearing cover bolt for fixing the bearing cover to the cylinder head, and the cylinder head is fixed to the cylinder block. A screw-in bolt is configured to pass through this opening.

Problems to be Solved by the Invention In U.S. Pat. There are problems such as having to pull the cylinder head and cylinder block together using nuts.
This method results in a significant increase in costs. Furthermore, the nut must be inserted into the larger diameter bore of the cylinder head before the overhead camshaft assembly C, and this is done using a large diameter hole that allows the bolt head or nut to pass through. This is because the diameter of the overhead camshaft is insufficient to provide a horizontal hole. Also, this known patent specification j
u1. Another disadvantage is that it requires extremely high costs to adequately lubricate the bearings.

This is because the above-mentioned perforation passes through the bearing surface, which causes problems such as a reduction in the projected interior of the bearing that supports the overhead camshaft and the formation of lubricating oil grooves.

In European Patent Nos. 0098180+ and Q, the bearing benefit bolt (11) must be installed at a position relatively far from the overhead camshaft, and in addition, in the area between the bearing cover bolt and the overhead camshaft, Since the bearing cover is weakened by the mountain road drilling, deformation of the bearing cover due to the biasing force of the valve bone moving toward the camshaft and the force generated by the accelerated mass cannot be completely eliminated.

In order to prevent this deformation, the bearing cover shown in this patent specification has the problem of being forced to have a strong and heavy construction.

An object of the present invention is to make it possible to fix a unit consisting of a cylinder head and an overhead camshaft to a cylinder block by means during a bend, and to at least fix an overhead camshaft that does not have any disadvantageous effect on supporting the overhead camshaft. The object of the present invention is to provide an internal combustion engine equipped with one engine.

Means for Solving the Problems In order to solve the above problems, the present invention provides an internal combustion engine comprising a cylinder block, a cylinder head fixed to the cylinder block by cylinder head bolts, and at least one overhead camshaft. In the above, the overhead camshaft is supported by a half-shaped bearing consisting of two receiving parts, one of the receiving parts is installed in the cylinder head, and the other of the receiving parts is attached to the cylinder head with a bearing cover. Provided in a bearing cover fixed by bolts, at least one bearing cover bolt and at least one cylinder head bolt are arranged coaxially, and the cylinder head bolt can pass through the bearing cover bolt. The present invention provides an internal combustion engine having at least one overhead camshaft characterized by an axial through hole formed therein.

Function According to this structure, the cylinder head and the overhead camshaft can be connected by attaching the bearing cover to the cylinder head using the bearing bolt with the through hole formed while the overhead camshaft is supported by the bearing. Unitized. after that,
When a cylinder head bolt is passed through the through hole, the unit is fixed to the cylinder block by the cylinder head bolt.

Cylinder heads are usually made of light metal with a relatively low permissible pressure per medium area. According to the invention, since the diameter of the axial through-bore of the bearing cap bolt is small, the diameter of the head or flange of the cylinder head bolt is also relatively small in accordance with this diameter. Therefore, in a preferred embodiment of the invention, an all-all sleeve is screwed into the cylinder head bore that receives the cylinder head bolt, and the end face of the sleeve is in contact with the head or flange of the cylinder head bolt.・Ru. By doing so, the tightening force of the bolt can be distributed to the threads of the sleeve, and tightening can be performed within the allowable pressure range of the material of the cylinder head.

Embodiment An embodiment of the present invention will be described in detail below with reference to the drawings.

A cylinder head 1, which is partially shown in cross-section in FIG. 1, is equipped with an overhead camshaft 2, which is supported on the cylinder head 1 by a bearing cover 3. The bearing for this overhead camshaft 2 is formed by two socket parts, one of which is located in the cylinder head 1 and the other socket part 5 is located in the bearing cover 3. It is being The bearing 'f: 3 shown in the drawing is
On the one hand, it is fixed to the cylinder head 1 by a bolt 6 (bearing cover bolt) that fits into the threaded hole 7 of the cylinder head 1, and on the other hand, it is a hollow hole that fits into the internal thread 9 cut in the mountain hole 10 of the cylinder head 1. 1 fixed to the cylinder head 1 by bolts 8 (bearing cover bolts);
A bore hole 11 is provided in the cylinder head 1 coaxially with the Sadamichi bore hole 10, and this bore hole 11 plays the role of accommodating a cylinder head bolt 12. It fits into the screw hole 13 and is used to fix the cylinder head 1 to the cylinder block 14. Hollow bolt 8-13
The inner diameter of the through hole 15 is sized to allow the cylinder head bolt 12 to pass through, so that the cylinder head 1 and the overhead camshaft 2 can be assembled together in advance. The unit can be screwed to the cylinder block 14 using cylinder head bolts 12.

Since the cylinder head 1 usually consists of a light metal alloy, it can only carry a relatively small pressure per medium area. f of hollow bolt 8! The diameter of the J through hole 15 is small, and therefore the diameter of the 7 flange 12a of the cylinder head bolt 12 formed as a #I polygonal flanged head bolt is also relatively small.
When tightened, excessive pressure force will be generated on the contact surface of the cylinder head 1.

In order to avoid excessive blood pressure horns, the borehole 11 is cut with an internal thread 18 and a steel sleeve 17 with a thread on the outer circumference is screwed into the internal thread 18.
7 langes 12 of the cylinder head bolt 12 on the end face of the cylinder head bolt 12
a is supported. With this configuration, the force for tightening the cylinder head bolt 12 is distributed to the threads of the sleeve 17, so that the force for tightening the cylinder head bolt 12 is distributed to the threads of the sleeve 17.
The surface of the area expands and the pressure per medium area decreases.

In this embodiment, the cylinder head bolt 12 is constructed as a flanged bolt with polygons.

The cylinder head bolt 12 may be constructed as a differential thread having two threads with different pitches. These two thread numbers with different pitches, cylinder block 1.
4 and the corresponding female thread cut in the cylinder head 1, and the pitch of the two threads is different,
The cylinder head 1 and cylinder block 14 are fixed.

Since such a yi initial screw does not have a head or a flange, the diameter of the through hole 15 and the outer diameter of the head of the hollow bolt 8 can be kept smaller.

The method of fixing the bearing cover 3 using hollow bolts 8 as shown in the figure is to attach the cylinder head 1 to the cylinder block 14.
It is necessary to provide a location above the bearing of the overhead camshaft 2 to fix it to ti! It becomes necessary in appropriate cases. If the cylinder head can be screwed in a location other than above the bearing,
Using a normal bolt such as the bearing cover bolt 6, do
The bearing cover 3 may be fixed to the cylinder head 1 on both sides of the camshaft 2 as usual. This is possible, for example, in the following cases: That is, two overhead camshafts are installed, and the screwing between the cylinder head 1 and the cylinder block 14 must be done in the area of the bearing only on one overhead camshaft side. , on the side of the other overhead camshaft, if the screwing of the cylinder head 1 can take place outside the area of the bearing of this other overhead camshaft.

As is clear from the drawing, the bearing cover bolt 6.8 as a fixing bolt for the bearing cover 3 is provided as close as possible to the overhead camshaft 2, which is caused by the force acting on the overhead camshaft 2 This is to prevent the lid 3 from deforming. The head of the hollow Jesilt is not a normal hexagonal shape, and the instep is equipped with a radial notch 16 for the tightening tool and bite stop, so that the hollow bolt 8 can be placed as close as possible to the overhead camshaft 2. .

Effects of the Invention Kokumei discovered that after assembling the cylinder head and overhead camshaft into a unit in advance, when this unit is screwed to the cylinder block using cylinder head bolts, the cylinder head bolts can pass through. Monkey <
By providing a through hole in the r-axis direction on the bearing cover bolt c), the cylinder head bolt and the bearing cover bolt can be placed coaxially at the same position, making it possible to install the overhead camshaft in the optimal location. Not only can the bearing cover bolt be installed near the bearing cover bolt, but also the cylinder head bolt can be installed at an optimal position without compromising its position with the bearing cover bolt.

Moreover, since no through holes are provided in the overhead camshaft or the receiving part, the projected area of the bearing that supports the overhead camshaft does not decrease, and the lubricating oil groove can be easily formed.

Furthermore, since unnecessary through-holes are not provided, the weight of the bearing lid can be reduced while maintaining the rigidity of the bearing lid.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional view of a cylinder head in which an overhead camshaft according to the present invention is pre-assembled on a cylinder block and screwed, and Fig. 2 is a cross-sectional view of a portion in which an overhead camshaft according to the present invention is pre-assembled and screwed.
FIG. 1... Cylinder head, 2... Overhead camshaft, 3...
・Bearing cover, 4.5... Bearing part, 6... Bearing cover bolt (bolt), 8... Bearing cover bolt (hollow 11; bolt), 12... Cylinder head bolt, 14... - Cylinder block, 15...through hole. Agent Moriki 6 HiroshiFigure 1

Claims (1)

[Claims] 1. An internal combustion engine comprising a cylinder block, a cylinder head fixed to the cylinder block by cylinder head bolts, and at least one overhead camshaft,
The overhead camshaft is supported by a half-shaped bearing consisting of two receiving parts, one of which is installed in the cylinder head, and the other of the receiving parts is attached to the cylinder head with a bearing cover bolt. Provided in the bearing lid to be fixed, at least one bearing lid bolt and at least one cylinder head bolt are arranged coaxially, and the bearing lid bolt has an axial direction through which the cylinder head bolt can pass. An internal combustion engine equipped with at least one overhead camshaft, characterized in that a through hole is formed therein. 2. The cylinder head is made of light metal, and the contact surface of the cylinder head with the cylinder head bolt is formed by the end face of a steel sleeve with threads on the outer circumferential surface, and this sleeve has a hole for accommodating the cylinder head bolt. An internal combustion engine comprising at least one overhead camshaft according to claim 1, wherein the overhead camshaft is screwed into the internal combustion engine.