JPH03260361A - Cylinder head structure - Google Patents

Abstract

PURPOSE:To increase rigidity with no increase of weight by connecting a camshaft supporting part, rocker shaft supporting part and a spark plug mounting part to each other by a plurality of reinforced parts arranged in a crossed shape. CONSTITUTION:In a cylinder head 2, a camshaft supporting part 18 is arranged on one side in the width direction and a spark plug mounting part 20 is arranged on the other side while providing a combustion chamber hollow place 12 of each cylinder in a lower side wall part 4. A camshaft supporting part 26 is arranged between the camshaft supporting part 18 and the spark plug mounting part 20 while connecting the lower side of the spark plug mounting part 20 to the lower side wall part 4. Here a rocker shaft supporting part 18 and an upper side wall part 10 are connected together by the first reinforced part 34 in the lengthwise direction, and said part 34 is connected to each of supporting parts 18, 26 by the second reinforced part 36 in the width direction. The first reinforced part 34, the spark plug mounting part 20, an upper side connection part 32 and the rocker shaft supporting part 18 are connected together by the third connection part 38.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a cylinder head structure, and particularly to a cylinder head structure that can effectively increase rigidity without increasing weight and reduce vibration noise.

[Conventional technology]

BACKGROUND ART Internal combustion engines, particularly four-cycle internal combustion engines, are provided with a valve mechanism and a spark plug in the cylinder head for cylinder intake/exhaust exchange and fuel combustion. A cylinder head structure in which a valve mechanism and a spark plug are provided is disclosed in, for example, Japanese Utility Model Application No. 63-34341. This publication discloses a cylinder head structure in which a spark plug is provided approximately at the center of each cylinder of the cylinder head, and two intake valves and two exhaust valves are provided on each side of the cylinder head in the width direction relative to the spark plug. In this case, the spark plug mounting part to which the spark plug of each cylinder is mounted, and the intake valve lifter mounting part and the exhaust valve lifter mounting part to which the valve lifters of the intake valve and the exhaust valve are mounted, are installed to extend in the width direction of the cylinder head. The first connecting rib of each cylinder is connected to a second connecting rib extending in the longitudinal direction of the cylinder head.
They are connected by connecting ribs.

[Problem that the invention seeks to solve]

By the way, examples of conventional cylinder head structures include those shown in FIGS. 7 to 9. In the figure, 102 is a cylinder head. This cylinder head 102 has a lower side wall 104 (in the direction of arrow A), one side wall 106 and another side wall 108 on each side in the width direction (direction of arrow B), and an upper side (in the direction of arrow B).
It has an upper wall portion 110 (in the direction of arrow C). The lower wall portion 104 is provided with five combustion chamber locations 112 for each cylinder (not shown), and two intake ports 114 and two exhaust ports 116 are provided each communicating with the five combustion chamber locations 112. An intake port 114 and an exhaust port 116 are provided facing each other in the width direction (direction of arrow B) with respect to the cylinder center line l.

The cylinder head 102 has a camshaft support portion 11B on the − side in the width direction (direction of arrow B) with respect to the cylinder center line l.
At the same time, the spark plug mounting part 1 is arranged on the other side in the width direction.
20 are installed. As a result, the camshaft support section 118 and the spark plug support section 120 are provided facing each other in the width direction (direction of arrow B), as shown in FIG. The camshaft support portion 118 is provided with a camshaft receiving surface 122. The spark plug mounting portion 120 is provided with a spark plug hole 124 . This spark plug mounting part 12
The 0 spark plug hole 124 communicates with the five combustion chamber holes 112. Further, a rocker shaft support portion 126 is disposed between the camshaft support portion 118 and the spark plug mounting portion 120. This rocker shaft support part 12
6 is provided with a rocker shaft support hole 128.

The camshaft support portion 118 is connected to the cylinder head 10.
The spark plug mounting portion 120 is connected to the one side wall portion 106 on the − side in the width direction (direction of arrow B) and the upper side wall portion 110 on the upper side (direction of arrow C).
It is connected to the other side wall part 108 on the other side (in the direction of arrow B) and the upper side wall part 110 on the upper side (in the direction of arrow C) by the other side connecting part 130 and the upper side connecting part 132, respectively. The spark plug mounting portion 120 also includes a rocker shaft support portion 1.
26 are integrally provided.

In such a conventional cylinder head structure, as described above, the rocker shaft support part 126 is integrally provided in the spark plug mounting part 120, so that the rocker shaft supported by the rocker shaft support part 126 can be A fluctuating load from a rocker arm (not shown) will be applied.

However, since the spark plug mounting portion 120 is formed thin, there is a risk of deformation due to a fluctuating load from a rocker arm (not shown). There is a problem that the other side connecting part 130 and the upper side connecting part 132, which are respectively connected to 110, lack rigidity. Further, the fluctuating load from the rocker arm (not shown) may similarly act on the camshaft support portion 118 and cause it to deform, and there is a problem that the rigidity may be insufficient depending on the side wall portion 106 and the upper wall portion 110. was there.

For this reason, there is a problem in that vibration noise becomes large due to insufficient rigidity to suppress the vibration force generated by the valve mechanism.

In order to eliminate such inconvenience, the spark plug mounting portion 120
If the camshaft supporting portion II8 is made thicker to increase the rigidity, vibration noise can be reduced, but the weight will increase, so there is a problem that the rigidity cannot be effectively increased.

[Purpose of the invention]

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to effectively increase rigidity without increasing weight, reduce vibration noise, and
The objective is to realize a cylinder head structure that does not cause an increase in cost.

[Means for solving problems]

In order to achieve this object, the present invention provides a camshaft support portion disposed on one side in the width direction with respect to the cylinder center line of the cylinder head, on one side wall portion on the − side in the width direction and on the upper side wall portion on the upper side. A spark plug mounting portion connected to each other and disposed on the other side in the width direction with respect to the cylinder center line of the cylinder head is connected to the other side wall portion on the other side in the width direction and the upper side wall portion, respectively. In the cylinder head structure, in which the rocker shaft support part is integrally provided with the spark plug mounting part, the rocker shaft support part and the upper wall part are connected in the longitudinal direction of the cylinder head, and in the upper and lower directions. The first reinforcing part, the camshaft support part, and the rocker shaft support part are connected to each other by a plate-shaped first reinforcing part extending in the width direction and the vertical direction of the cylinder head. The first reinforcing part, the spark plug mounting part, the upper connecting part, and the rocker shaft supporting part extend in the width direction and the vertical direction of the cylinder head. A plate-shaped third reinforcing portion is provided to connect the spark plug mounting portion, the other side wall portion, and the other side connecting portion in the radial direction and the vertical direction of the cylinder head. 4th of
It is characterized by being connected by a reinforcing part.

[Effect]

According to the configuration of the present invention, the camshaft support portion, the rocker shaft support portion, and the spark plug mounting portion are connected to each other by the first to fourth reinforcement portions that intersect in a cross shape, and are connected to one side wall portion and the other side wall portion. The upper wall section is connected to the upper wall section.

〔Example〕

Next, embodiments of the present invention will be described in detail based on the drawings.

1 to 6 show embodiments of this invention. In the figure, 2 is a cylinder head.

This cylinder head 2 consists of a lower side wall 4 on the lower side (in the direction of the arrow), one side wall 6 and the other side wall 8 on each side in the width direction (in the direction of the arrow B), and an upper side wall 10 on the upper side (in the direction of the arrow C). It has The lower wall portion 4 is provided with five combustion chamber locations 12 for each cylinder (not shown), and two intake boats 14 and two exhaust ports 16 are provided each communicating with the five combustion chamber locations 12. An intake boat 14 and an exhaust boat 16 are provided facing each other in the width direction (direction of arrow B) with respect to the cylinder center line l.

The cylinder head 2 has a camshaft support portion 18 disposed on one side in the width direction (in the direction of arrow B) with respect to the cylinder centerline E, and a spark plug mounting portion 20 on the other side in the width direction. As a result, the camshaft support portion 18 and the spark plug mounting portion 20 are connected in the width direction (
They are provided facing each other in the direction of arrow B). The camshaft support portion 18 is provided with a camshaft receiving surface 22 . The spark plug mounting portion 20 is provided with a spark plug hole 24 . This ignition plug mounting part 20 has a lower side connected to a lower wall part 4.
The spark plug hole 24 is connected to the combustion chamber 5.
It connects to location 12. In addition, the camshaft support portion 18
A rocker shaft support portion 26 is disposed between the spark plug mounting portion 20 and the spark plug mounting portion 20 . This rocker shaft support part 2
6 is provided with a rocker shaft support hole 28.

The camshaft support portion 18 includes one side wall portion 6 on the − side in the width direction (arrow B direction) of the cylinder head 2 and the upper side (arrow C direction).
direction) are connected to the upper side wall portion 1o, respectively. The spark plug mounting portion 20 is provided on the other side wall portion 8 on the other side in the width direction (in the direction of arrow B) and on the upper side wall portion 10 on the upper side (in the direction of arrow C).
They are connected to each other by the other side connecting part 30 and the upper side connecting part 32, respectively. Further, a rocker shaft support portion 26 is integrally provided in the spark plug mounting portion 20.

In such a cylinder head structure, the rocker shaft support part 26 and the upper wall part 10 are arranged to extend in the longitudinal direction (arrow direction) and the vertical direction (arrow A-C direction) of the cylinder head 2. They are connected by a plate-shaped first reinforcing part 34.

The first reinforcing portion 34, the camshaft support portion 18, and the rocker shaft support portion 26 are installed to extend in the width direction (arrow B direction) and up and down direction (arrow A-C direction) of the cylinder head 2. They are connected by a plate-shaped second reinforcing section 36. Further, the first reinforcing portion 34, the spark plug mounting portion 20, the upper connecting portion 32, and the rocker shaft supporting portion 26 are attached to the cylinder in the width direction of the rod 2 (arrow B
direction) and the up-down direction (direction of arrows A-C). Further, the spark plug mounting portion 20, the other side wall portion 8, and the other side connecting portion 30 are connected in the width direction of the cylinder head 2 (arrow B
direction) and the up-down direction (direction of arrows A-C).

In other words, the thickness of the first reinforcing portion 34 extending in the longitudinal direction (arrow direction) of the cylinder head 2 connected to the rocker shaft supporting portion 26 and the upper wall portion 10 is the same as that of the camshaft supporting portion 18. Thickness in the width direction of cylinder head 2 (
A second reinforcing portion 36 extending in the direction of arrow B) is provided, and the second reinforcing portion 36 connects the first reinforcing portion 34, the camshaft support portion 18, and the rocker shaft support portion 26.

Further, the third reinforcing portion 38 has a thickness smaller than the thickness of the other side connecting portion 30 from the other side connecting portion 30 to the first reinforcing portion 34 in the width direction of the cylinder head 2 (in the direction of arrow B). ), and this third reinforcing part 38 strengthens the first reinforcing part 34.
The spark plug mounting portion 20, the upper connecting portion 32, and the rocker shaft support 26 are connected to each other.

Further, the fourth reinforcing part 40 is formed in the width direction of the cylinder head 2 (in the direction of arrow B) from the other side connecting part 30 to the first reinforcing part 34 with a thickness thinner than the thickness of the other side connecting part 30. ), and the fourth reinforcing portion 30 connects the spark plug mounting portion 20, the other side wall portion 8, and the other side connecting portion 30.

The second to fourth reinforcing parts 36 to 40 are provided so as to intersect with the first reinforcing part 34 and to be located in the same plane.

As a result, the first to fourth reinforcing parts 34 to 40 are arranged in a criss-cross pattern, as shown in FIG.
6 and the spark plug mounting portion 20 are connected to each other, and also connected to the recessed portion 6 on one side, the wall portion 8 on the other side, and the upper wall portion 10.

Further, in this embodiment, the camshaft support portion 18
and the second reinforcing portion 3 that connects the rocker shaft support portion 26.
6 is provided with a reinforcement oil passage 46 that communicates between the shaft oil passage 44 in the rocker shaft 42 supported in the rocker shaft support hole 28 of the rocker shaft support part 26 and the camshaft receiving surface 22 of the camshaft support part 18. There is. This reinforcement oil passage 46 includes a rocker shaft 42,
It is provided to penetrate the rocker shaft support part 26, the second reinforcement part 36, and the camshaft support part 18.

In this way, the camshaft support part 18, the rocker shaft support part 26, and the spark plug mounting part 20, which are connected by the first to fourth reinforcing parts 34 to 40, The first to fourth reinforcing parts 34 to 40 are arranged in a crisscross shape by extending in the direction (direction of arrow B), respectively, and are connected to each other by the first to fourth reinforcing parts 34 to 40, and the one side wall part 6, the other side wall part 8, and the upper wall. 10.

Thereby, the rigidity can be effectively increased without increasing the weight due to making the camshaft support part 18 and the spark plug mounting part 20 thicker, and vibration noise can be reduced. In addition, since the first to fourth reinforcing parts 34 to 40 are all shaped so that the bottom shape can be formed by molding, there is no increase in cost, and the assembly can be performed in the same process as conventional ones. It does not cause a decrease in assemblability.

Further, a rocker shaft 42 is attached to a second reinforcing portion 36 that connects the camshaft support portion 18 and the rocker shaft support portion 26.
The shaft oil passage 44 inside the camshaft support part 18
Reinforcement oil passage 4 communicating with zero force shaft receiving surface 22
6, it is possible to ensure the lubricity of the camshaft while effectively utilizing the constituent members of the cylinder head 2.

〔Effect of the invention〕

As described above, according to the present invention, the camshaft support section, the rocker shaft support section, and the spark plug mounting section are arranged in a criss-cross shape by extending in the longitudinal direction and the width direction of the cylinder head, respectively. The first to fourth reinforcing portions are connected to each other and to the one side wall, the other side wall, and the upper wall.

Thereby, the rigidity can be effectively increased without increasing the weight due to thickening the camshaft support part and the spark plug mounting part, and vibration noise can be reduced. In addition, the first to fourth reinforcing portions are all shaped so that the bottom shape can be formed by molding, so there is no increase in cost.
Moreover, since the assembly can be carried out in the same steps as conventional ones, there is no problem in assembling performance.

[Brief explanation of drawings]

1 to 6 show examples of the cylinder head structure according to the present invention, in which FIG. 1 is a sectional view taken along the line I--I in FIG. The drawings are a sectional view taken along the line ■--■ of FIG. 2, FIG. 4 is a side view of an example of the cylinder head, FIG. 5 is a plan view of the cylinder head, and FIG. 6 is a side view of the other side of the cylinder head. 7 to 9 show conventional examples of cylinder head structures.
The figure is a sectional view taken along the line ■-■ in Figure 9, and Figure 8 is a cross-sectional view taken along the line ■-■ in Figure 9.
9 is a plan view of the cylinder head. In the figure, 2 is a cylinder head, 4 is a lower wall, 6 is one side wall, 8 is another side wall, 10 is an upper wall, 12 is 5 combustion chamber locations, 14 is an intake boat, 16 is an exhaust boat, 18
is the camshaft support part, 20 is the spark plug mounting part, 26
30 is the other side connecting portion, 32 is the upper connecting portion, 34 is the first reinforcing portion, 36 is the second reinforcing portion, 38
Reference numeral 40 indicates a third reinforcing portion, numeral 40 indicates a fourth reinforcing portion, and numeral 46 indicates a reinforcing portion oil passage.

Claims (1)

[Claims] 1. A camshaft support part disposed on one side in the width direction with respect to the cylinder center line of the cylinder head is connected to the one side wall part on the one side in the width direction and the upper wall part on the upper side, respectively. A spark plug mounting portion disposed on the other side in the width direction with respect to the cylinder centerline is connected to the other side wall portion and the upper wall portion on the other side in the width direction by the other side connecting portion and the upper side connecting portion, respectively, and In a cylinder head structure in which a rocker shaft support part is integrally provided in the spark plug mounting part,
The rocker shaft support portion and the upper wall portion are connected to each other by a plate-shaped first reinforcing portion extending in the longitudinal direction and the vertical direction of the cylinder head, and the first reinforcing portion and the camshaft supporting portion are connected to each other. and the rocker shaft support part are connected by a plate-shaped second reinforcing part extending in the width direction and the vertical direction of the cylinder head, and the first reinforcing part, the spark plug mounting part, and the upper connection and the rocker shaft support part are connected to each other by a plate-shaped third reinforcing part extending in the width direction and the vertical direction of the cylinder head, and the spark plug mounting part, the other side wall part, and the other side A cylinder head structure characterized in that the connecting portion is connected to the connecting portion by a plate-shaped fourth reinforcing portion extending in the width direction and the vertical direction of the cylinder head.