JP2957458B2 - Lubrication structure of valve train - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lubrication structure for a valve train in an engine.

[0002]

2. Description of the Related Art The valve train of a four-stroke engine has
Since then, there has been one disclosed in JP-A-63-90648.
You.

According to this, the cylinder of an engine is
Head is in contact with the head body and the top surface of the head body.
Head cover that covers the top of the head body.
The dividing line between the head body and the head cover is a virtual plane
It is located above. These head body and head cover
The internal spaces of the bar are communicated with each other,
A cam formed and having a shaft center extending horizontally in this valve cam chamber.
Axis is provided, freely rotating the cams shaft about an axis thereof
A cam bearing is provided to support the head body.
Have been.

A cam nose rotary gauge constituting the cam shaft
A lubricating oil reservoir member that covers the trace from below is provided.
The lubricating oil sump member is provided in the internal space of the head body.
With the lower member being viewed from the line of sight along the axis of the camshaft.
Thus, the cylinder is inclined with respect to a vertical line.

[0005] Then, by the rotation of the cam shaft, cam noses constituting the camshaft intake, by contact member and the sliding of the exhaust valve side, and is adapted to open and close the intake and exhaust valves at a predetermined timing .

In the above case, the lubricating oil reservoir member
Is supplied with lubricating oil that has scattered in the valve cam chamber.
The lubricating oil accumulated by this,
Adhering to the cam nose of the rotating camshaft, this adhering
With the lubricating oil, the cam nose of the cam shaft and the suction and exhaust
The sliding part with the member on the valve side is lubricated
I have.

[0007]

THE INVENTION It is a problem to be solved point the way, the circular
When mounting the gin on a motorcycle, tilt the cylinder
Sometimes you want to increase the slope.
As a result, the lubricating oil sump member also becomes larger
The lubrication oil can be stored in the lubrication oil storage member
Available capacity is reduced, and as a result,
The amount of lubricating oil adhering is reduced and lubrication of the sliding contact
There is a risk of becoming sufficient.

Accordingly, the lubricating oil in the lubricating oil reservoir
To prevent the liquid level from dropping, lubricate the lubricating oil reservoir
It is desirable to increase the supply, but this way
It is not easy to do.

[0009]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has a cylinder which is greatly inclined with respect to a vertical line.
Supply of lubricating oil to the lubricating oil storage member
It is an object of the present invention to sufficiently achieve lubrication of a sliding portion of a camshaft with a cam nose even if the amount is small .

[0010]

The features of the present invention for achieving the above object are as follows.

[0011] In the section "Configuration of the invention",
The terms in parentheses below correspond to the terms in the claims.
It responds.

That is, the feature of the above is that the cylinder
One cylinder head 4 is composed of a head body 7 and this head book.
To cover the upper surface of the head body 7 by joining to the upper surface of the body 7.
Head cover 7 and a head cover.
-8 is located on the imaginary plane.
The internal space of the head cover 7 and the head cover 8 communicate with each other and operate.
A valve cam chamber 15 is formed, and an axial center is formed in the valve cam chamber 15.
A horizontally extending intake camshaft (camshaft) 21 is provided.
The air cam shaft (cam shaft) 21 is rotatable around its axis.
The first cam bearing (cap) supported on the head body 7
Bearing 22) and the intake camshaft (camshaft) 21
The first to third cam nose (cam nose) 21a,
Lubrication that covers the rotation trajectory 30 of 21b and 21c from below.
An oil sump member 31 is provided, and the lubricating oil sump member 31
The lower member 31b provided in the internal space of the head body 7
And a view along the axis of the intake camshaft (camshaft) 21.
When the cylinder 1 is tilted with respect to the vertical
In the lubrication structure of the valve mechanism,

[0013] The lubricating oil sump member 31 is connected to the head cap.
Provided in the internal space of the bar 8 and connected to the lower member 31b
In that an upper member 31a is provided .

[0014]

[Operation] The operation of the above configuration is as follows.

In the section of "action",
The terms in parentheses correspond to the terms in the claims.
Things.

The first part of the intake camshaft (camshaft) 21 is as follows.
~ 3rd cam nose (cam nose) 21a, 21b, 21
The lubricating oil reservoir member 3 that covers the rotation trajectory 30 from below.
1 and the lubricating oil reservoir member 31
The first cam bearing (cam bearing) 22 is provided in the internal space.
Molded integrally with the lower bearing case (bearing case) 22b
The intake camshaft (camshaft) 21 includes a lower member 31b.
Looking at the line of sight along the axis, the cylinder 1
In the lubrication structure of the valve mechanism that is tilted and tilted,

The lubricating oil sump member 31 is connected to the head cap.
Provided in the internal space of the bar 8 and connected to the lower member 31b
An upper member 31a is provided.

That is, the rotation trajectory 30 corresponds to the cylinder
In addition to the lower member 31b provided in the internal space of the head 4,
And provided in the internal space of the head cover 8 and
By the upper member 31a connected to the member 31b,
The cylinder will be covered from below,
In accordance with the large inclination of the lubricating oil reservoir 1, the lubricating oil reservoir member
Even if 31 is greatly inclined, as described above,
By adding the material 31a, the lubricating oil sump 31
Is sufficient to store the lubricating oil 28 '
It is.

Therefore, the first to third cam nose (cam
Nose) Apply lubricating oil 28 'to 21a, 21b, 21c
The first to third cam nose with sufficient amount of
(Cam nose) Moisture of sliding contact with 21a, 21b, 21c
The lubrication will be sufficient.

As a result, as described above, the cylinder 1
Even when the intake cam is tilted greatly with respect to the vertical,
First to third cam nose (cam nose) of shaft (cam shaft) 21
G) lubrication of the sliding contact portions with 21a, 21b, 21c
With a small amount of lubricating oil 28 'supplied to the lubricating oil sump member 31,
This will be fully achieved.

[0021]

Embodiments of the present invention will be described below with reference to the drawings.

In FIG. 1, reference numeral 1 denotes a cylinder of a four-stroke engine, which is mounted on a motorcycle. At this time, the cylinder 1 is in a forwardly inclined posture. The arrow Fr in the figure indicates the front of the vehicle in the traveling direction.

The cylinder 1 has a cylinder block 3 having a piston 2 therein, and a cylinder head 4 mounted on the upper surface of the cylinder block 3. 5 is a combustion chamber.

The cylinder head 4 comprises a head body 7 attached to the upper surface of the cylinder block 3 and a head cover 8 joined to the upper surface of the head body 7 to cover the upper surface of the head body 7 so as to be openable and closable. The head main body 7 is formed with an intake port 9 and an exhaust port 10 communicating with the combustion chamber 5. In addition, each of these ports 9 and 1
An intake valve 12 and an exhaust valve 13 for opening and closing the valve 0 are provided, and the stems 12a and 13a of the valves 12 and 13 are slidably supported by the head body 7.

A DOHC valve operating mechanism 14 for opening and closing the valves 12 and 13 at a predetermined timing is provided. Hereinafter, the valve train 14 will be described.

The head body 7 of the cylinder head 4 is
Each internal space of the head cover 8 is communicated with each other.
A valve cam chamber 15 is formed by the internal space , that is, a space surrounded by the head body 7 and the head cover 8 is the valve cam chamber 15. The upper ends of the stems 12a and 13a protrude into the valve cam chamber 15.

A circular guide hole 16 is formed on the inner bottom surface of the valve cam chamber 15 coaxially with the stems 12a and 13a.
An intake lifter 18 is fitted to one guide hole 16 and an exhaust lifter 19 is fitted to the other guide hole 17 slidably in the axial direction. The intake lifter 18 is joined to the upper end of the stem 12a of the intake valve 12, and the exhaust lifter 19 is joined to the upper end of the stem 13a of the exhaust valve 13. A spring 20 for urging the lifters 18, 19 together with the stems 12a, 13a toward the valve operating cam chamber 15 is provided, and the urging causes the valves 12, 13 to correspond to the corresponding ports. 9 and 10 are closed.

An intake camshaft 21 having a horizontal axis and extending parallel to each other in the vehicle width direction is provided in the valve operating cam chamber 15 in correspondence with the intake lifter 18. The intake camshaft 21 includes first and second bearings 22 and 2 serving as cam bearings.
3, the valve cam chamber 15 is rotatably supported on the inner bottom surface of the valve cam chamber 15 around its axis. And, this intake camshaft 21
Has first to third cam noses 21a, 21b, 21c at positions sandwiching the bearings 22, 23.

Further, an exhaust cam shaft 25 having a horizontal axis and extending in the vehicle width direction is provided corresponding to the exhaust lifter 19. The exhaust camshaft 25 is formed by a bearing 26
The exhaust camshaft 25 also has a cam nose 25a supported on the inner bottom surface of the valve operating cam chamber 15 so as to be rotatable around its axis.

Each of the camshafts 21 and 25 is linked to a crankshaft (not shown). When these camshafts 21 and 25 rotate, the cam nose 21a, 21b, 21c,
25a comes into sliding contact with the corresponding lifters 18 and 19 and the spring 2
This is pushed against the urging force of 0, and each port 9, 10 is opened and closed at a predetermined timing. In this case, each guide hole 1 is passed through a lubricating oil passage from an oil pump (not shown).
Lubricating oil is supplied to the sliding contact portions between the lifters 18, 19 and the lifters 18, 19 and the sliding contact portions between the lifters 18, 19 and the camshafts 21, 25, and these sliding contact portions are lubricated. Reference numeral 28 in the drawing indicates the level of the lubricating oil when the valve train 14 is stopped.

Each bearing case of each of the bearings 22, 23, 26 is divided into upper and lower halves, and the upper bearing case 22a, 2
3a, 26a and lower bearing cases 22b, 23b, 26b
It is composed of Then, the lower bearing case 22b,
23b and 26b are integrally formed on the head body 7 side, and upper bearing cases 22a, 23a and 26a are detachably screwed to these by fasteners 29. In the above case, the score lines of the head body 7 and the head cover 8, the upper bearing cases 22a, 23a, 26a and the lower bearing case 22
b, 23b, 26b are located on the same virtual plane
Sasera are.

The front cylinder 1 as noted is tilted forward
However, more specifically, along the axis of the intake camshaft 21
Looking at the line of sight (Fig. 1), the cylinder 1
It is inclined forward. This inclination, the intake lifter 18 and the intake camshaft 21 is positioned above the side of the exhaust lifter 19 and the exhaust camshaft 25, therefore, the intake lifters 18 and intake camshaft 21 is a valve operating cam chamber 15
Far away from the bottom of the

The protruding end of the intake lifter 18 into the valve operating cam chamber 15 and the cam nose 21 a, 2
A lubricating oil reservoir member 31 is provided to cover both the lower part of the rotation locus 30 of 1b and 21c from below. The scattered lubricating oil 28 'is stored in the lubricating oil storage member 31, and the lubricating oil 28' is lubricated by oil bathing the sliding portions. In this case, the lubricating oil reservoir member 31 is provided sufficiently close to the protruding end of the intake lifter 18 and the rotation trajectory 30 of the cam nose 21a, 21b, 21c.
1 prevents the amount of the lubricating oil 28 'from becoming unnecessarily large.

The lubricating oil reservoir member 31 is divided into upper and lower parts, and is separated from each other as an upper member 31a and a lower member 31b.
Is formed by the upper member 31a is of the head cover 8
The upper bearing case 22a, 2
3a is integrally formed by casting . Hand, the lower member 31b is disposed in the inner space of the head main body 7
The lower bearing cases 22b and 23b and the head body 7 are integrally formed by casting . And above f
The upper surface of the head body 7 so as to cover the upper surface of the head body 7
When the head cover 8 is joined to the upper member 31a,
Are connected to the lower member 31b .

[0035] Incidentally, the lubricating oil sump member 31 also functions as a reinforcing member of each bearing case. In the above case, the dividing line between the upper member 31a and the lower member 31b is located on the same imaginary plane as the dividing line between the head body 7 and the head cover 8, and the opposing surfaces of these dividing lines are sufficiently sealed. I have.

[0036]

According to the present invention, the cylinder of the cylinder
The head is joined to the head body and the top of this head body.
A head cover that covers the upper surface of the lever head body,
The dividing line between the head body and the head cover is on the virtual plane
Located inside each of the head body and head cover
Are communicated with each other to form a valve operating cam chamber.
A camshaft whose axis extends horizontally is provided in the room, and this camshaft is
Support the head body so that it can rotate around its axis.
A cam bearing for supporting the camshaft is provided.
A lubricating oil reservoir that covers the rotation trajectory of the
In this case, the lubricating oil sump member is provided in the internal space of the head main body.
A lower member provided along the axis of the camshaft.
When viewed from the line of sight, the cylinder is tilted with respect to the vertical line.
In the lubrication structure of the valve mechanism,

The lubricating oil sump member is provided with the head cover
The upper member provided in the internal space of and connected to the lower member
Is provided.

That is, the rotation locus is determined by the cylinder head.
In addition to the lower member provided in the internal space of the
Provided in the internal space of the cover and connected to the lower member
It will be covered from below by the upper member,
For this reason, a large inclination of the cylinder is required.
Even if the lubricating oil sump
As noted above, the addition of the upper member
Enough capacity to store lubricating oil in the reservoir member
Is done.

Therefore, adhesion of lubricating oil to the cam nose
A sufficient amount is ensured, and the lubrication
The lubrication will be sufficient.

As a result, as described above, the cylinder is
Even if the camshaft is tilted significantly with respect to the straight line, the camshaft
The lubrication of the sliding contact with the
This can be achieved sufficiently with a small amount of lubricating oil.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view taken along line II of FIG.

FIG. 2 is a plan view of a valve operating mechanism.

[Explanation of symbols]

Reference Signs List 1 cylinder 4 cylinder head 7 head body 8 head cover 14 valve operating mechanism 15 valve operating cam chamber 21 intake camshaft (camshaft) 21a first cam nose ( cam nose) 21b second cam nose (cam nose) 21c third cam nose (cam nose) 22nd first bearing (cam bearing) 23 second bearing (cam bearings) 22a, 23a upper bearing case (bearing case) 22b, 23b lower bearing case (bearing case) 28, 28 'lubricating oil 30 rotational path 31 lubricating oil sump member 31a on Member 31b lower member

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) F02F 1/24 F01L 1/04 F01L 1/12 F01M 9/06

Claims (1)

(57) [Claims] The cylinder head of a cylinder is a head body.
And joined to the upper surface of this head body
A head cover for covering the upper surface, and
The dividing line with the head cover is located on the virtual plane,
The internal space of the head body and the head cover
A valve-operated cam chamber is formed, and the shaft center is set horizontally in this valve-operated cam chamber.
Provide an extended camshaft and rotate this camshaft around its axis
A cam bearing to be supported on the head body so that it can be freely
And the rotation locus of the cam nose that constitutes the camshaft
A lubricating oil sump member for covering the lubricating oil sump from below.
A lower member provided in the internal space of the head body
When viewed from the line of sight along the axis of the camshaft,
In a lubricating structure of a valve mechanism in which a cylinder is inclined with respect to a vertical line , the lubricating oil reservoir member is provided in an inner space of the head cover.
A lubrication structure for a valve mechanism including an upper member provided and connected to the lower member .