JPH1122438A - Oil passage structure of engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To supply an oil having a proper hydraulic pressure to an oil control unit and other oil feed parts by providing a restriction part in a position parallel to the oil control unit connected to an oil passage within a cylinder head or in the middle of the oil passage in the downstream side from it. SOLUTION: In an engine having an oil passage 54 provided within a cylinder head 6 and an oil control unit(OC/U) within the oil passage 54, a throttle part 60 is provided in a position parallel to the OC/U 56 or in the middle of the oil passage 54 in the downstream from the OC/U 56. This restriction part 60 is formed of a suction side restriction part 60-1 and an exhaust side restriction part 60-2, which are interposed in the middle of the suction side oil passage 54-3 and exhaust side oil passage 54-4 branched from the oil passage 54-3 of main oil passage, respectively. Thus, an oil having a proper hydraulic pressure can be supplied to the OC/U 56 and the oil feed parts of a suction cam shaft 30 and an exhaust cam shaft 32, so that the lubricating performance can be improved.

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 of an engine, and more particularly, to a throttle portion provided in a position parallel to an oil control unit or in the middle of an oil passage downstream of the oil control unit. While oil is supplied, oil passing through the throttle portion is supplied in a position parallel to the oil control unit or downstream of the oil control unit, and the appropriate oil pressure is supplied to the oil control unit and other oil supply parts. The present invention relates to an engine oil passage structure that can be supplied.

[0002]

2. Description of the Related Art In a normal engine, oil is supplied to a camshaft through an oil passage independent of a main gallery of a cylinder block and to a cam housing of the camshaft. Since the oil supply to the camshaft is smaller than that of the crank system, an orifice is inserted near the cylinder head gasket.

[0003] As the oil passage structure of the engine,
There is one disclosed in Japanese Utility Model Laid-Open No. 60-114216. The lubricating oil passage structure of the cylinder head disclosed in this publication is provided with a bolt insertion hole in the cylinder head, the cylinder head is fixed to the cylinder block with a bolt inserted in the insertion hole, and between the inner periphery of the insertion hole and the bolt. A gap is formed, and the gap forms a lubricating oil passage.

[0004] Japanese Unexamined Utility Model Publication No. Hei 3-97513 discloses a method. A cylinder head structure of an internal combustion engine disclosed in this publication provides a bolt head and a cylinder head in an internal combustion engine in which a bolt mounting hole provided in the cylinder head and fastening the head to a cylinder block also serves as a lubricating oil passage. A flat washer is interposed between the upper surface and the upper surface, and a groove is formed on the abutting surface between the flat washer and the upper surface of the cylinder head for communicating the lubricating oil passage with the outside air to release air in the lubricating oil. .

[0005] Furthermore, there is one disclosed in Japanese Utility Model Laid-Open No. 4-82306. The engine lubrication device disclosed in this publication includes a cylinder block in which a cylinder head portion that defines a combustion chamber between a cylinder and a piston is integrally formed, and oil from an oil main gallery is applied to a side wall of the cylinder block. An oil hole leading to the valve train on the cylinder head is drilled, and a stud bolt is also provided on the side wall of the cylinder block, which is screwed orthogonally to the oil hole, and an orifice is formed through the stud bolt to narrow down the oil hole. ing.

[0006]

In a conventional engine oil passage structure, for example, a structure having an orifice near a cylinder head gasket, there is no problem when used in a normal engine. in the engine provided with the oil control unit such as a hydraulic control unit for a variable valve timing, the hydraulic pressure on the downstream side of the oil passage than said orifice, 4kgt / cm ² approximately from 1kgt / cm ²
As a result, there is a disadvantage that the oil control unit cannot be operated accurately.

[0007] Further, there is a fear that the assembling of the orifice may be forgotten at the time of molding the engine, and an improvement has been sought.

For this reason, there is a measure to omit the orifice inserted near the cylinder head gasket.

That is, as a measure, a groove of a stud bolt is used as disclosed in Japanese Utility Model Application Laid-Open No. 4-82306.

However, if the independent orifice is omitted, it is necessary to accurately process the groove shape of the stud bolt and the hole diameter of the cylinder block in order to accurately adjust the amount of oil to the camshaft. This is disadvantageous in that it is disadvantageous in practical use, is difficult to manufacture, increases costs, and is economically disadvantageous.

[0011]

SUMMARY OF THE INVENTION In order to eliminate the above-mentioned disadvantages, the present invention provides an engine having an oil control unit provided with an oil passage in a cylinder head and connected to the oil passage. A throttle portion is provided in the side-by-side position or in the middle of the oil passage downstream of the oil control unit.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION
When the engine is driven, the oil is supplied to the oil control unit, and the oil that has passed through the throttle portion is supplied in a position parallel to the oil control unit or downstream of the oil control unit. The appropriate hydraulic oil is supplied to each.

[0013]

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

1 to 6 show an embodiment of the present invention. In FIG. 4, reference numeral 2 denotes a four-cylinder four-cycle engine, 4 denotes a cylinder block, 6 denotes a cylinder head, and 8 denotes a cylinder head cover.

As shown in FIGS. 5 and 6, the engine 2 is provided with a crankshaft 10 supported below a cylinder block 4 and a plurality of cylinders 12 provided above the cylinder block 4.

The connecting rod 14 is connected to the crankshaft 10.
The piston 16 which reciprocates in the cylinder 12 is connected by this.

A cylinder head 6 is attached to the cylinder block 4 so as to be in contact therewith. A combustion chamber 18 is formed by the cylinder block 4, the cylinder head 6, and the piston 16.
As shown in FIG. 6, an ignition plug 20 is provided, and the cylinder head cover 8 is attached to the cylinder head 6 in contact therewith.

Further, the cylinder block 4 has a structure shown in FIG.
As shown in FIG. 5, an intake port 22 and an exhaust port 24 are provided, the intake port 22 is formed on the intake side (left side in FIGS. 5 and 6) with respect to the cylinder axis of the cylinder head 6, and one end side is connected to the combustion chamber 18. It is formed linearly so as to communicate with it and open the other end side above the cylinder head 6. As shown in FIG. 4, the intake port 22
Two are provided for every eight.

The exhaust port 24 is connected to the cylinder head 6
5 and 6, one end is communicated with the combustion chamber 18 and the other end is directed to the exhaust side (right in FIGS. 5 and 6). Form. As shown in FIG. 4, one exhaust port 24 is provided for each combustion chamber 18.

An intake port 22 is provided on the cylinder head 6.
And an intake valve 26 and an exhaust valve 28 for opening and closing the exhaust port 24, respectively.

Further, an intake camshaft 30 and an exhaust camshaft 32 are provided on the upper surface of the cylinder head 6 by an intake cam housing 34 and an exhaust cam housing 36, respectively. The exhaust cam 40 of the shaft 32 opens and closes the intake valve 26 and the exhaust valve 28. That is, as shown in FIG. 2, the intake cam housing 34 and the exhaust cam housing 36 are connected to the cylinder head 6 by an intake camshaft bolt 42 and an exhaust camshaft bolt 44.
Mounted on top.

A downstream side of the intake manifold 46 is mounted on the upper surface of the cylinder head cover 8, and an upstream side of the intake manifold 46 is provided so as to communicate with a surge tank 48 and a throttle body 50. Further, a manifold intake passage 52 communicating with the intake port 22 is formed in the intake manifold 46.

In the cylinder head 6 of the engine 2,
As shown in FIG. 2, an oil passage 54 is provided, and an oil control unit 56 such as a hydraulic control unit for variable valve timing connected to the oil passage 54 is provided.
Is provided.

That is, as shown in FIG. 2, an oil control unit 56 is provided on the left side of the cylinder head 6 so as to communicate with a main gallery (not shown) on the cylinder block 4 side and extend in the cylinder axis direction of the cylinder head 6. An oil passage 54-1 is provided, the second oil passage 54 extending in a direction perpendicular to the cylinder axis of the cylinder head 6 communicating with the upper end of the first oil passage 54-1 and communicating with the oil control unit 56. -2, the first and second oil passages 54-
A main oil passage is formed by 1, 54-2. At this time, the left end in FIG. 2 which is one end of the second oil passage 54-2 communicates with the oil control unit 56,
In FIG. 2 as the other end, the right end is closed by a blind plug 58.

Then, the oil control unit 25
And oil control unit 56
Downstream, for example, the oil control unit 56
The throttle section 60 is provided in the middle of the oil passage 54 on the downstream side.

More specifically, the throttle section 60 is composed of an intake-side throttle section 60-1 and an exhaust-side throttle section 60-2, and the intake-side throttle section 60-1, as shown in FIG. In the intake-side third oil passage 54-3, which branches from the second oil passage 54-2 of the main oil passage communicating with the unit 56 and communicates with the oil supply portion of the intake camshaft 30, the intake-side camshaft An outer peripheral portion of the bolt 42 and an intake-side head knock hole 62 of the cylinder head 6 through which the intake-side camshaft bolt 42 is inserted are formed in the middle of the intake-side third oil passage 54-3 serving as the branch oil passage.

Further, the exhaust-side restricting portion 60-2 is provided as shown in FIG.
And the oil control unit 56 as shown in FIG.
The fourth oil passage 54-4 is a branch oil passage that branches from the second oil passage 54-2 of the main oil passage that communicates with the oil supply portion of the exhaust camshaft 32.
, The exhaust-side fourth oil passage 54-4 serving as the branch oil passage is formed by the outer peripheral portion of the exhaust-side camshaft bolt 44 and the exhaust-side head knock hole 64 of the cylinder head 6 through which the exhaust-side camshaft bolt 44 is inserted. Formed on the way.

Further, the throttle section 60 will be further described along the exhaust-side throttle section 60-2 in FIG. 1. The exhaust-side throttle section 60-2 is formed of the large-diameter section 44a in the middle of the exhaust-side camshaft bolt 44. It is set by the difference between the outer diameter D and the inner diameter d of the exhaust side head knock hole 64. The description of the intake-side throttle unit 60-1 is omitted because it has the same configuration as that of the exhaust-side throttle unit 60-2.

Reference numeral 66 denotes a first groove 68 formed in the intake cam housing 34 for connecting the intake-side third oil passage 54-3 to an in-shaft oil passage 30a formed in the intake camshaft 30. Is a second groove formed in the exhaust cam housing 36 for connecting the fourth exhaust oil passage 54-4 and the oil passage 32a in the shaft formed in the exhaust camshaft 32, and 70 is a spark plug of the spark plug 20. A guide, 72 is an injector, 74 is an induction air passage, and 76 is sensors.

Next, the operation will be described.

When the engine 2 is driven and approximately 4 kgt / cm ² of oil is supplied to the first oil passage 54-1 from a main gallery (not shown), the oil passes through the second oil passage 54-2 and is controlled by the oil control. Unit 56
Is supplied to the oil control unit 56, and there is no problem in the operation of the oil control unit 56.

The oil that has reached the second oil passage 54-2 passes through the third oil passage 54-3, the first groove 66, and the in-shaft oil passage 30a.
0 is supplied to the oil supply portion. At this time, the oil passes through the intake-side throttle portion 60-1 formed in the middle of the third oil passage 54-3, so that the intake-side throttle portion 60
By -1, the oil pressure becomes 1 kgt / cm ² or less, and an appropriate oil pressure state is obtained.

Further, the oil that has reached the second oil passage 54-2 passes through the fourth oil passage 54-4, the second groove 68, and the in-shaft oil passage 32a.
2 oil supply sites. Then, at this time, the oil passes through the exhaust-side throttle portion 60-2 formed in the middle of the fourth oil passage 54-4, so that the exhaust-side throttle portion 60
Due to -2, the oil pressure becomes 1 kgt / cm ² or less, and an appropriate oil pressure state is obtained.

Thus, the oil control unit 56, the intake camshaft 30, and the exhaust camshaft 32 are supplied with appropriate oil pressure by the throttle 60 provided in the middle of the oil passage 54 downstream of the oil control unit 56. Oil can be supplied, which is practically advantageous.

The oil control unit 5
Although the configuration is for the engine 2 having the engine 6, it can also be used as a normal type engine without the oil control unit 56 installed, and the versatility can be increased.

Further, since there is no need to dispose an orifice in the oil passage 54, there is no danger that the orifice is forgotten during the molding of the engine.
The assemblability can be improved.

Further, the intake-side throttle portion 60-1 and the exhaust-side throttle portion 60-2 of the throttle portion 60 are connected to the outer diameter D of the large-diameter portion in the middle of the intake-side camshaft bolt 42 and the intake-side head knock hole. By setting the difference between the inner diameter d of the exhaust-side camshaft bolt 44 and the inner diameter d of the exhaust-side head knock hole 64, the machining is facilitated. It is practically advantageous. That is, the intake side camshaft bolt 42 and the exhaust side camshaft bolt 44 can be dealt with only by polishing the outer peripheral part, and the intake side head knock hole 62 and the exhaust side head knock hole 64 have the camshaft bolt hole 64. In this case, the reaming process may be performed while using the parts, similarly to the processing of the knock hole portions of the intake cam housing 34 and the exhaust cam housing 36.

It should be noted that the present invention is not limited to the above-described embodiment, and various application modifications are possible.

For example, in the embodiment of the present invention, the throttle portion is provided in the middle of the oil passage downstream of the oil control unit.
It can be provided in a position parallel to the oil control unit.

[0040]

According to the present invention, as described in detail above, an oil passage is provided in a cylinder head,
In the engine having the oil control unit communicating with the oil passage, the throttle portion is provided in a position parallel to the oil control unit or in the middle of the oil passage downstream of the oil control unit. An oil pressure of appropriate hydraulic pressure can be supplied to the oil control unit and other oil supply portions by a throttle portion provided in the middle of the oil passage on the downstream side, which is practically advantageous. Further, although the configuration is for an engine having the oil control unit, it can also be used as a normal type engine without an oil control unit, which can increase versatility. Further, since there is no need to dispose an orifice in the middle of the oil passage, there is no fear of forgetting to assemble the orifice at the time of molding the engine.
The assemblability can be improved.

[Brief description of the drawings]

FIG. 1 is an enlarged cross-sectional view of a main part of a camshaft bolt according to an embodiment of the present invention, taken along the arrow 〓 in FIG.

FIG. 2 is an enlarged sectional view taken along line II-II of FIG.

FIG. 3 is a plan view of the engine.

FIG. 4 is a plan view of a cylinder head.

FIG. 5 is a cross-sectional view of the engine taken along a valve center and a port center.

FIG. 6 is a cross-sectional view of the engine cut by a cylinder center.

[Explanation of symbols]

 Reference Signs List 2 engine 4 cylinder block 6 cylinder head 8 cylinder head cover 10 crankshaft 18 combustion chamber 20 spark plug 22 intake port 24 exhaust port 26 intake valve 28 exhaust valve 30 intake camshaft 32 exhaust camshaft 34 intake cam housing 36 exhaust cam housing 38 intake Cam 40 Exhaust cam 42 Intake side camshaft bolt 44 Exhaust side camshaft bolt 46 Intake manifold 54 Oil passage 54-1 First oil passage 54-2 Second oil passage 54-3 Third oil passage 54-4 Fourth oil passage 56 Control unit 60 Throttle section 60-1 Intake side throttle section 60-2 Exhaust side throttle section 62 Intake side head knock hole 64 Exhaust side head knock hole 66 First groove 68 Second groove

Claims (2)

[Claims] 1. An engine having an oil passage provided in a cylinder head and having an oil control unit connected to the oil passage, a throttle portion is provided in a position parallel to the oil control unit or in the middle of the oil passage downstream of the oil control unit. An oil passage structure for an engine, wherein the oil passage structure is provided. 2. An outer peripheral portion of a camshaft bolt for mounting a cam housing on a cylinder head in a branch oil passage branching from a main oil passage communicating with an oil control unit and communicating with an oil supply site of a camshaft. The engine oil passage structure according to claim 1, wherein the branch oil passage is formed in the middle of the branch oil passage by a head knock hole of the cylinder head through which the camshaft bolt is inserted.