JP2586547Y2 - Engine head structure - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an engine head structure in which a frame-shaped rocker cover and a lid-shaped head cover are mounted on a cylinder head in an overlapping manner and an intake chamber is formed therein.

[0002]

2. Description of the Related Art FIG. 4 shows a head structure of an OHV engine developed by the present applicant, FIG. 5 is a perspective view of a rocker cover thereof, and FIG. 6 is a sectional view taken along line VI-VI of FIG. .

As shown in the figure, a frame-shaped rocker cover 4 for accommodating a rocker arm 3 is attached to a cylinder head 2 having a plurality of intake ports 1 opened on the upper surface.
On this rocker cover 4, a lid-like head cover 5 is attached so as to cover the rocker arm 3 and the intake port 1.

[0004] A partition wall 6 is provided in the rocker cover 4 along the direction of the crankshaft. The partition wall 6 allows the inside of the cover 4 to accommodate the rocker arm 3 in a rocker chamber 4 a.
And an intake chamber 4b surrounding the intake port 1.
On the other hand, inside the head cover 5, a partition rib 7 formed to be continuous with the partition wall 6 is provided.

According to this configuration, the intake air sucked from the intake port 8 of the head cover 5 is guided into the intake chamber 9 defined by the partition rib 7 and the partition wall 6, and from the intake chamber 9 to each intake port. 1 to each cylinder.

[0006]

However, the following problems occur in the above-described head structure.

[0007] The intake air flowing from the intake chamber 9 to each cylinder through each intake port 1 is prevented from flowing smoothly by the cylinder head bolt 10 projecting into the intake chamber 9 when flowing into the intake port 1. Therefore, the intake resistance increases and a remarkable decrease in the intake efficiency occurs. The cylinder head bolt 10 is attached from above to attach the cylinder head 2 to the cylinder body 11, and has to protrude from the upper surface 2 a of the cylinder head 2 in the intake chamber 9.

[0008] In general, it is known that the length of the intake port 1 is increased in order to increase the intake efficiency in a low-speed region of the engine. However, no consideration is given to the above structure. That is, in the above configuration, there is room for increasing the intake port 1 to further increase the intake efficiency in the middle to low speed range.

SUMMARY OF THE INVENTION An object of the present invention, which has been made in view of the above circumstances, is to prevent a disturbance of intake air due to a cylinder head bolt protruding into an intake chamber and to extend a substantial intake port length of an engine. Is to provide.

[0010]

According to the present invention, a frame-shaped rocker cover for accommodating a rocker arm is mounted on a cylinder head having a plurality of intake ports opened on an upper surface thereof. Inside the cylinder
Partition each intake port opened on the top of the pad
A partition member that extends the intake port length, and the partition member
Was opened on the top of the rocker cover
The edges of the air inlet are formed in an R shape, and all of the air inlets are
Cover the head cover on the top of the rocker cover.
Attach the above intake ports inside the head cover
It is characterized in that a common intake chamber is formed .

[0011]

Since a partition member for partitioning each intake port is provided inside the rocker cover forming the intake chamber, the substantial length of the intake port is extended by the length of the partition member, and the intake efficiency in a medium to low speed region is improved. Increase.

Further, the partition wall member covers the cylinder head bolt protruding from the upper surface of the cylinder head, so that the turbulence of the flow of intake air flowing into each intake port from the intake chamber is prevented. In addition, the partition member
Edges of air inlets opened on top of rocker cover
Is formed into an R shape, so that the edge of the
And the intake air resistance can be reduced.
You. Also, attach the head cover to the top of the rocker cover.
All air intake ports inside the head cover.
The common intake chamber and the common intake chamber
With each intake port extended by the partition member,
Structure like an intake manifold in the engine head
It can be configured without increasing the number of components.

[0013]

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

As shown in FIG. 1, the cylinder body 11
Further, a cylinder head 2 having a plurality of intake ports 1 opened on the upper surface is attached by a cylinder head bolt 10. A frame-shaped rocker cover 4 that accommodates and supports the rocker arm 3 and the rocker shaft 12 is mounted on the cylinder head 2 as shown in FIG. A lid-like head cover 5 is mounted on the rocker cover 4 so as to cover the rocker arm 3, the rocker shaft 12, and the intake port 1, and an intake chamber 9 is formed therein.

More specifically, a partition wall 6 for partitioning the inside of the rocker cover 4 in the direction of the crankshaft is provided in the rocker cover 4, and as shown in FIG. 1 is divided into an intake chamber 4b. In the rocker chamber 4a, ribs 13 are provided at intervals in a direction perpendicular to the crankshaft. The rocker shaft 12 is inserted and supported in support holes 14 formed in the ribs 13, and the ribs 13 are partitioned. Room 1
The rocker arm 3 is accommodated in 5. On the other hand, inside the head cover 5, a partition rib 7 formed to be continuous with the partition wall 6 is provided. According to this configuration,
The intake air sucked from the intake port 8 of the head cover 5 is introduced into each cylinder through each intake port 1 through an intake chamber 9 defined by a partition rib 7 and a partition wall 6.

This embodiment is characterized in that a partition member 1 that partitions each intake port 1 opened on the upper surface 2a of the cylinder head 2 is provided inside the rocker cover 4 on the intake chamber 4b side.
6 is provided integrally. These partition members 16
As shown in FIG. 1, in order to extend the substantial intake port 1 length, the intake port 1 is formed so as to be smoothly connected to each intake port 1. As shown in FIG. 3 (b), the intake port 17 opened to the upper surface 4a of the rocker cover 4 by the partition member 16 has an R-shaped edge, and an edge shape as shown in FIG. 3 (a). In this case, the contraction phenomenon that occurs in the case of (1) is prevented, and the reduction of the effective port area (φd <φD) is prevented. As shown in FIG. 1, these partition members 16 are formed in the shape of a thin inverted container having an open lower surface, and are mounted so as to cover the cylinder head bolts 10 protruding from the upper surface of the cylinder head 2. .

The operation of this embodiment having the above configuration will be described.

A partition member 16 for partitioning each intake port 1 opened on the upper surface of the cylinder head is provided inside the rocker cover 4.
Are provided integrally, the substantial length of the intake port 1 is increased by the height of the partition member 16 without increasing the number of components. Therefore, the inertia supercharging effect in the middle to low speed range is enhanced.

The partition member 16 is formed in the shape of an inverted container having an open lower surface, and covers the cylinder head bolt 10 protruding from the upper surface 2a of the cylinder head 2. Therefore, the cylinder head bolt 10 does not protrude into the intake chamber 9, and the disturbance of the flow of the intake air caused by the head bolt 10 is prevented, and the intake resistance is reduced and the air is smoothly sucked.

Further, since the edge of the intake port 17 opened on the upper surface 4a of the rocker cover 4 is formed into an R shape by the partition member 16, the flow contraction phenomenon that occurs when the edge is formed is prevented, and the intake resistance is reduced. Is further reduced, and the intake efficiency is improved.

The head cover 5 provided with the ribs 7
Is attached to the upper surface of the rocker cover 4 to form an intake chamber 9 common to each intake port 1 inside the head cover 5.
With each intake port 1 extended by 6, a structure such as an intake manifold can be formed in the head portion of the engine. In this case, since the head cover 5 not only covers the rocker arm 3 but also contributes to the formation of the intake chamber 9 common to the intake ports 1 by the ribs 7, the head cover 5 can be configured without increasing the number of parts.

[0022]

According to the present invention as it has been described above devised], b
Partition wall inside the cover to extend the actual intake port length
Material, and the edge of the intake port opened by the partition member
Part is rounded, and the head is
With a suction cover common to each intake port.
Because the air chamber was formed,
A structure like an intake manifold is built in the engine head.
As a result, the inertial supercharging effect can be enhanced by extending the substantial intake port length, and the intake resistance can be reduced by covering the cylinder head bolt protruding into the intake chamber.

[Brief description of the drawings]

FIG. 1 is an explanatory view of an engine head structure showing one embodiment of the present invention, and is a cross-sectional view taken along line II of FIG. 2;

FIG. 2 is a perspective view of a rocker cover constituting the head unit structure.

FIG. 3 is a cross-sectional view of an air inlet opening on the upper surface of the rocker cover.

FIG. 4 is a cross-sectional view showing a structure of a head portion of an engine previously developed by the present applicant.

FIG. 5 is a perspective view of a rocker cover previously developed by the present applicant.

FIG. 6 is a sectional view taken along the line VI-VI of FIG. 4;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Intake port 2 Cylinder head 2a Cylinder head upper surface 3 Rocker arm 4 Rocker cover 5 Head cover 9 Intake chamber 16 Partition member

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) F02F 7/00 F01L 1/12 F02M 35/102 F16M 1/026

Claims (1)

(57) [Scope of request for utility model registration] 1. A frame-shaped rocker cover for accommodating a rocker arm is mounted on a cylinder head having a plurality of intake ports opened on an upper surface, and a cylinder is provided inside the rocker cover.
Partitions each intake port opened on the top of the head and
Partition member that extends the typical intake port length, and the partition portion
Material is opened on the top of the rocker cover.
The edge of the intake port is formed into an R shape, and all of the intake ports
Cover on the top of the rocker cover.
And attach each of the above intake ports inside the head cover.
The engine's head structure has a common intake chamber .