JPH0996207A - Oil passage structure of cylinder head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To aim at prevention of bubbles from being generated in residual oil so as to attempt improvement of lubricating performance in each sliding part of an engine by providing a groove for oil dropping in an oil sump part and providing an oil guide wall for guiding the oil from the groove for oil dropping to an oil pan side on the cylinder head inside wall. SOLUTION: A groove 90 for oil dropping is provided in an oil sump part positioned above either one of an intake air side oil sump part 84 and an exhaust side oil sump part 88 in the case of a slant engine 2. Below this groove 90 for oil dropping on a cylinder head inner wall 92, an oil guide wall 94 for guiding the oil coming from the groove 90 for oil dropping to the oil pan side is provided. Residual oil dropping from the oil sump part 84 is guided from the groove 90 for oil dropping to the oil guide wall 94, not allowed to flow to intake/exhaust valve spring 24, 26 side, but smoothly guided to the oil pan side. In this way, no bubble may be generated in the residual oil so that the durability is improved together with improvement in the lubricating performance of each sliding part of an engine.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an oil passage structure for a cylinder head, and more particularly to an oil passage structure for a cylinder head capable of preventing bubbles from being generated in excess oil.

[0002]

2. Description of the Related Art A cylinder head of an engine mounted on a vehicle is provided with an intake / exhaust port communicating with a combustion chamber,
There is one in which an intake / exhaust valve for opening / closing these intake / exhaust ports is provided, and an intake / exhaust cam shaft that rotates to drive these intake / exhaust valves is provided.

As such an engine, there is one shown in FIGS. That is, in FIGS. 5 to 7, 202 is an engine, 204 is a cylinder block, and 206 is a cylinder head. The cylinder head 206 is provided with intake / exhaust ports 210/212 communicating with the combustion chamber 208, and intake / exhaust valves 214/216 for opening / closing the intake / exhaust ports 210/212.

The intake / exhaust valves 214/216 are provided with intake / exhaust hydraulic tappets 218/220. The intake / exhaust hydraulic tappets 218/220 include intake / exhaust tappet bodies 222/224 and intake / exhaust adjusters 226/2.
And 28. Air intake / exhaust tappet body 222 ・ 22
4 is a suction / exhaust boss portion 230 of the cylinder head 206.
The support holes 234 and 236 for suction and exhaust of 232 are provided so as to support them respectively.

The intake / exhaust valves 214/216 are urged by intake / exhaust valve springs 240/242 supported on the inner wall 138 of the cylinder head.

The cylinder head 106 is provided with intake / exhaust cam shafts 244 and 246 that are axially supported. The intake / exhaust cam shafts 244, 246 have intake / exhaust cams 248.2
50 are provided. The intake and exhaust cams 248 and 250 are
It is in contact with the intake / exhaust tappet bodies 222 and 224.

The cylinder head 206 is provided with an intake side wall portion 252 on the intake hydraulic tappet 218 side and an exhaust side wall portion 254 on the exhaust hydraulic tappet 220 side, and a connecting portion between the intake and exhaust hydraulic tappets 218, 220. 256 is provided.

The cylinder head 206 is provided with main oil passages 258 and 260 for intake and exhaust in the axial direction (longitudinal direction) of the cam shafts 238 and 248 for intake and exhaust, and the main oil passages 258 and 260 for intake and exhaust are provided. Intake / exhaust communication oil passages 262/264 are provided to supply oil to the intake / exhaust adjusters 226/228.

Further, in the cylinder head 206, an intake side oil reservoir 268 is formed by the intake side wall portion 252 and the intake side oil reservoir wall 266, and an exhaust side oil by the exhaust side wall portion 254 and the exhaust side oil reservoir wall 270. A reservoir 272 is provided. Intake / exhaust side oil reservoir 268 ・
The excess oil of the oil supplied to the intake / exhaust hydraulic tappets 218 and 220 is stored in 272. The surplus oil stored in the intake / exhaust side oil reservoirs 168/272 lubricates the sliding portions between the intake / exhaust cams 242/244 and the intake / exhaust tappet bodies 222/224.

Further, the cylinder head 206 is provided with intake / exhaust oil drop holes 274/276 for guiding the excess oil falling from the intake / exhaust oil sump portions 268/272 to an oil pan (not shown). .

An oil passage structure for such a cylinder head is disclosed, for example, in Japanese Patent Application Laid-Open No. 6-26316. The one described in this publication has an oil flow space formed between the outer peripheral surface of the plug pipe of the cylinder head and the inner peripheral surface of the plug mounting hole extending in the axial direction of the plug.
With this oil circulation space, an oil passage directed toward the crank shaft center on one side of the plug pipe and an oil passage directed toward the crank shaft center on the other side are connected at different positions.

[0012]

By the way, in the structure of the cylinder head shown in FIGS. 5 to 7, the excess oil overflowing from the intake / exhaust oil sump portions 268/272 travels along the cylinder head inner wall 238 and is absorbed. Exhaust oil drop hole 27
It is introduced into an oil pan (not shown) via 4 · 276.

At this time, since the excess oil flows under the intake / exhaust valve springs 240/242, the expansion / contraction of the intake / exhaust valve springs 240/242 causes the excess oil to be agitated, and bubbles are formed in the excess oil. appear.

Therefore, the oil containing bubbles drops in the oil pan and is again pumped from the oil pump (not shown) to each part of the engine, so that the lubrication performance of each sliding part deteriorates and the oil is absorbed. The exhaust hydraulic tappets 218 and 220 have malfunctions, and the functions thereof are deteriorated, and the durability is also deteriorated.

[0015]

Therefore, in order to eliminate the above-mentioned inconvenience, the present invention provides an intake / exhaust valve for opening / closing an intake / exhaust port communicating with a combustion chamber of a cylinder head of an engine.・ Providing suction / exhaust hydraulic tappets on the exhaust valves respectively, and directly hitting these suction / exhaust hydraulic tappets to rotate in the same direction to drive the intake / exhaust valves.
An exhaust camshaft is provided, an intake oil reservoir is formed on the intake hydraulic tappet side of the cylinder head by an intake oil reservoir wall, and an exhaust oil reservoir wall is formed on the exhaust hydraulic tappet side of the cylinder head. In the oil passage structure of the cylinder head in which the exhaust side oil sump portion is formed, when the engine is tilted, the oil sump portion located above either the intake side oil sump portion or the exhaust side oil sump portion is Is provided with an oil dropping groove, and an oil guide wall for guiding the oil from the oil dropping groove to the oil pan side is provided on the inner wall of the cylinder head below the oil dropping groove.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION According to the present invention, excess oil that falls from an oil sump located above either the intake side oil sump or the exhaust side oil sump is guided to the oil guide wall from the oil drop groove. It will not flow to the intake / exhaust valve spring side and will be smoothly guided to the oil pan side. As a result, air bubbles do not occur in the excess oil, the lubrication performance of each sliding part of the engine is improved, the durability is improved, the performance of the engine is improved, and in the conventional space. It is feasible, does not add weight, and is inexpensive.

[0017]

Embodiments of the present invention will be described in detail and specifically with reference to the drawings.

1 to 4 show an embodiment of the present invention. In FIGS. 3 and 4, 2 is an engine for a multi-cylinder mounted on a vehicle, 4 is a cylinder block, 6 is a cylinder head, and 8 is a head cover.

The cylinder head 6 has one combustion chamber 10
At least two intake / exhaust ports 12, which communicate with the
14 are provided, and each of these two intake / exhaust ports 12.1.
Two intake / exhaust valves 16 and 18 for opening and closing 4 are provided. The intake and exhaust valves 16 and 18 are intake and exhaust valve shafts 20 and 2.
The intake / exhaust valve springs 24/26 that give the elastic force in the valve closing direction to
It is supported by 0. Intake / Exhaust valve spring 24
26 is supported by a cylinder head inner wall 92 described later.

The intake / exhaust valve shafts 20 and 22 of the two intake / exhaust valves 16 and 18 respectively have hydraulic tappets 3 for intake / exhaust, respectively.
2.34 is provided. The two intake / exhaust hydraulic tappets 32, 34 are respectively the intake / exhaust tappet bodies 36, 38.
And intake / exhaust adjusters 40 and 42. The intake / exhaust tappet bodies 36/38 are provided with intake / exhaust support holes 48.5 of the intake / exhaust boss portions 44/46 of the cylinder head 4.
0 are slidably supported in the axial direction.

The cylinder head 6 is provided with one intake / exhaust camshaft 52/54, and another intake / exhaust camshaft housing 5 is provided.
It is rotatably supported by 6.58. The intake / exhaust cam shafts 52, 54 are rotated in a predetermined direction in conjunction with a crank shaft (not shown). The intake / exhaust cam shafts 52 and 54 have
Two intake and exhaust cams 60 and 62 are provided respectively. The intake / exhaust cams 60, 62 are respectively brought into contact with the intake / exhaust tappet bodies 36, 38 to open and close the intake / exhaust valves 16, 18.

In addition, the cylinder head 6 is provided with an intake side wall portion 64 on the intake hydraulic tappet 32 side in the width direction intersecting the axial direction of the intake / exhaust camshafts 52, 54, and the exhaust hydraulic tappet in the width direction. The exhaust side wall portion 66 is provided on the 34 side, and the connecting portion 6 is provided between the intake and exhaust hydraulic tappets 32 and 34.
8 is provided to connect between the intake / exhaust bosses 44 and 46. The connecting portion 68 is provided with a spark plug boss portion 70,
A spark plug hole 72 communicating with the combustion chamber 10 is provided.

The cylinder head 6 is provided with intake / exhaust main oil passages 74/76 in the axial direction (longitudinal direction) of the intake / exhaust cam shafts 52/54.
Intake / exhaust communication oil passages 78/80 for supplying the 76 oil to the intake / exhaust adjusters 40/42 are provided. The intake main oil passage 74 and the intake communication oil passage 78 are configured so as to bypass the spark plug hole portion 72 and
It is provided at a connecting portion 68 between the exhaust boss portions 44 and 46. The exhaust main oil passage 76 and the exhaust communication oil passage 80 are provided on the exhaust side wall portion 66 side of the exhaust boss portion 46.

Further, the cylinder head 6 is provided with an intake side oil sump portion 84 between the intake side wall portion 64 and the intake side oil sump wall 82 between the intake hydraulic tappet 32 and the exhaust side wall portion 66 and the exhaust side oil sump portion 84. An exhaust side oil reservoir 88 is provided between the reservoir wall 86 and the exhaust hydraulic tappet 34. The intake / exhaust side oil sump portions 86/88 are respectively provided between the two intake / exhaust hydraulic tappets 32/34 and the intake / exhaust side oil sump walls 82/86, respectively.

In the intake / exhaust side oil reservoirs 84/88,
Excess oil supplied to the intake and exhaust hydraulic tappets 32 and 34 is stored. Intake / exhaust side oil sump 84/88
Excess oil stored in the intake / exhaust cams 60/62
Lubricate the sliding parts between the intake and exhaust tappet bodies 36 and 38.

The engine 2 is installed with a slight inclination to the right as shown in FIGS.

Then, for example, an oil drop groove 90 is formed in the intake side oil reservoir wall 82 located above.

Below the oil dropping groove 90, the cylinder head inner wall 92 has oil guide walls 94, 94 on both sides of the intake / exhaust side valve springs 24, 26 as shown in FIGS. Erected. The oil guide walls 94, 94 prevent excess oil from flowing toward the intake / exhaust side valve springs 24, 26.

Further, the cylinder head 6 is provided with intake / exhaust oil drop holes 96/98 for guiding excess oil from the cylinder head inner wall 92 to an oil pan (not shown).

In FIG. 4, reference numeral 100 is an ignition coil.

Next, the operation of this embodiment will be described.

In the cylinder head 6, the oil flows through the intake / exhaust main oil passages 74/76 and the intake / exhaust communication oil passages 78/80 to suck / exhaust hydraulic tappets 32/34.
Is supplied to.

Excess oil discharged from the outer circumference of the intake hydraulic tappet 32 serves to lubricate the intake cam 60,
It is stored in the intake oil sump portion 84.

The surplus oil overflowing from the intake oil sump 84 drops from the oil drop groove 90 to the cylinder head inner wall 92, is guided to the oil guide wall 94, reaches the intake oil drop hole 96, and is returned to the oil pan. Be done.

At this time, since the oil guide walls 94 are provided on both sides of the intake valve spring 24 as shown in FIG. 4, excess oil does not flow into the lower surface of the intake valve spring 24, and the oil pan side is provided. Be smoothly guided to.

As a result, the excess oil is not agitated by the intake valve spring 24, and bubbles are not generated in the excess oil.

As a result, the lubrication performance of each sliding portion of the engine 2 is improved, and the durability can be improved.

Further, the intake / exhaust hydraulic tappets 32/34 can be operated reliably, and the engine performance can be improved.

Further, since it can be easily dealt with in the conventional space, the weight is not increased and the cost can be reduced.

In this embodiment, the oil drop groove 90 is provided only on the intake oil reservoir wall 82, but the oil drop groove 90 may be provided on the exhaust oil reservoir wall 86.

[0041]

As is apparent from the above detailed description, according to the present invention, the oil sump portion located above either the intake side oil sump portion or the exhaust side oil sump portion when the engine is inclined. Since an oil drop groove is provided in the oil drop groove, and an oil guide wall for guiding the oil from the oil drop groove to the oil pan side is provided on the inner wall of the cylinder head below the oil drop groove, bubbles are generated in the excess oil. Without increasing the lubrication performance of each sliding part of the engine, improving the durability and improving the performance of the engine,
In addition, it can be carried out in the conventional space, the weight does not increase, and the cost can be reduced.

[Brief description of drawings]

1 is a cross-sectional view of the engine taken along the line 〓-〓 of FIG.

2 is a cross-sectional view of the engine of FIG.

FIG. 3 is a partial plan view of a cylinder head.

FIG. 4 is a cross-sectional view taken along line IV-IV of FIG.

5 is a cross-sectional view of an engine of the related art taken along the line 〓-〓 of FIG.

6 is a cross-sectional view taken along line 〓-〓 of FIG. 7 in the related art.

FIG. 7 is a partial plan view of a conventional cylinder head.

[Explanation of symbols]

 2 engine 6 cylinder head 16 intake valve 18 exhaust valve 24 intake valve spring 26 exhaust valve spring 84 intake oil sump 88 exhaust oil sump 90 oil drop groove 92 cylinder head inner wall 94 oil guide wall

Claims (2)

[Claims] 1. An intake / exhaust valve for opening / closing an intake / exhaust port communicating with a combustion chamber of a cylinder head of an engine is provided, and intake / exhaust hydraulic tappets are provided to the intake / exhaust valve, respectively.
An intake / exhaust camshaft that rotates in the same direction to drive the intake / exhaust valve by directly hitting the intake / exhaust hydraulic tappet is provided, and an intake-side oil sump is provided on the intake hydraulic tappet side of the cylinder head. In an oil passage structure of a cylinder head in which an intake side oil sump is formed by a wall and an exhaust side oil sump is formed by an exhaust side oil sump wall on the exhaust hydraulic tappet side of the cylinder head, the engine is inclined. In this case, an oil drop groove is provided in the oil drop section located above either the intake side oil drop section or the exhaust side oil drop section, and the oil drop groove is provided below the oil drop groove on the cylinder head inner wall. An oil passage structure for a cylinder head, which is provided with an oil guide wall for guiding the oil from the oil drop groove to the oil pan side. 2. The oil guide walls are provided on both sides of the valve spring so as to prevent the oil from the oil drop groove from flowing toward the valve spring side of the intake / exhaust valve. The oil passage structure for a cylinder head according to claim 1, characterized in that.