JP2534156Y2 - Lubricating oil passage structure of internal combustion engine - Google Patents

Description

The present invention relates to a lubricating oil passage structure of an internal combustion engine, and more particularly to a lubricating oil passage structure of an internal combustion engine that can achieve good lubrication even when the internal combustion engine is started. .

2. Description of the Related Art In an internal combustion engine, a lubricating oil is supplied to a moving part of each part to lubricate a contact surface in order to protect a moving part of each part.

As such a lubricating oil supply structure, for example,
7 are shown in FIGS. That is, a block-side oil passage for guiding lubricating oil pumped by driving an oil pump (not shown) is provided in the cylinder block 104 of the internal combustion engine 102.
122 are formed.

In the cylinder head 106, an oil rising passage 124 communicating with the block-side oil passage 122, an oil introduction passage 142 communicating with the oil rising passage 124, and a main oil passage 128 communicating with the oil introducing passage 142, An oil distribution passage 138 as an auxiliary oil passage for guiding lubricating oil from the main oil passage 128 to the cam shaft 108 or the rocker arm shaft 110 side.
1, 138-2, 138-3, 138-4, and 138-5.

An oil jet 126 is provided in the middle of an oil rising passage 124 communicating with the main oil passage 128.

Further, as shown in FIGS. 8 and 9, an oil rising passage 224 may be directly connected to the main oil passage 228, and an oil jet 226 may be provided in the middle of the oil rising passage 224.

Furthermore, as shown in FIG. 10, a main oil passage 328 is formed in the cylinder head 306 in parallel with the camshaft 308, and a plurality of hydraulic lash adjusters 344 are provided. Some have a structure in which lubricating oil is supplied from the tank.

Further, as the structure of the lubricating oil passage of the internal combustion engine, for example,
This is disclosed in Japanese Utility Model Laid-Open No. 57-101307. 57-57
Japanese Patent Application Laid-Open No. 101307 discloses a configuration in which a branch passage that branches from a main passage and guides lubricating oil to a valve train is provided, and a check valve that prevents backflow is provided in the branch passage.

[Problems to be Solved by the Invention] In the conventional lubricating oil passage structure of the internal combustion engine, when the internal combustion engine stops and the operation of the oil pump is stopped, the oil distribution passage in the oil distribution passage communicating with the main oil passage is stopped. The lubricating oil flows down to the main oil passage side, and flows down to the lower cylinder block side via the oil rising passage.

Therefore, when the internal combustion engine is restarted, there is no lubricating oil in the oil rising passage, the main oil passage, and the oil distribution passage of the cylinder head, and the operation of the internal combustion engine drives the oil pump. Also, there is a disadvantage that lubricating oil is not supplied immediately to each part of the camshaft and the journal portion, resulting in poor lubrication.

Also, as shown in FIG. 6, the oil jet 126 provided in the middle of the oil rising passage 124 is processed in two steps to have a large diameter hole 126a for the oil jet 126 and a small diameter hole 126b for the throttle. Therefore, there are disadvantages that the production becomes difficult, the cost becomes large, and it is economically disadvantageous.

Further, as shown in FIG. 10, a hydraulic lash adjuster
In the internal combustion engine 302 having the 344, air is supplied to the hydraulic lash adjuster when the internal combustion engine is restarted, and therefore, there is a disadvantage that the hydraulic lash adjuster malfunctions and abnormal noise occurs.

[Object of the Invention] Accordingly, an object of the invention is to provide an oil rising passage having an oil rising passage having a circular cross section in a lubricating oil passage structure of an internal combustion engine in order to eliminate the above-mentioned disadvantages. Into the main oil passage to form a throttle section by the inner peripheral surface of the main oil passage, the outlet end portion of the oil rising passage that contacts this inner peripheral surface, and the upper end of the oil jet. It is an object of the present invention to provide a lubricating oil passage structure for an internal combustion engine that allows lubricating oil to remain in a main oil passage and instantly supply the remaining lubricating oil to the camshaft when the internal combustion engine is restarted, thereby achieving good lubrication. .

[Means for Solving the Problems] In order to achieve this object, the present invention provides an oil rising passage having a circular cross section formed in a cylinder head for introducing lubricating oil from a cylinder block side of an internal combustion engine and this oil. A main oil passage having a circular cross section which is directed to an axial direction of a cam shaft held by the cylinder head while being connected to the up passage, and a plurality of oil distribution passages for guiding lubricating oil from the main oil passage to each part of the cam shaft; In the lubricating oil passage structure for an internal combustion engine having an oil jet passage, an oil jet is interposed at an upper end side of the oil rising passage, and the oil rising passage is made to enter the main oil passage, and an inner peripheral surface of the main oil passage and an inner peripheral surface of the inner oil passage are formed. A throttle portion is constituted by an outlet end portion of the oil rising passage that comes into contact with the peripheral surface and an upper end of the oil jet.

[Operation] According to the configuration of the present invention, when the internal combustion engine is stopped, the lubricating oil is not pumped from the oil pump, so that the lubricating oil in each oil passage in the cylinder head flows from the oil rising passage to the cylinder block side. Although it flows down, lubricating oil remains in the main oil passage at a position lower than the throttle portion. Then, when the internal combustion engine is restarted, the lubricating oil remaining in the main oil passage is instantaneously supplied to the camshaft side,
The lubrication on the camshaft side is improved to protect the moving parts of each part.

Embodiment An embodiment 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 the figure, 2 is an internal combustion engine, 4 is a cylinder block, 6
Is a cylinder head, 8 is a cam shaft, 10 is a rocker arm shaft,
12 is a cylinder head cover.

The camshaft 8 is sealed at its end with a sealing material 14 and rotatably held on the cylinder head 6 by a plurality of cam caps 16.

As shown in FIG. 4, a cam 18 is provided on the camshaft 8, and the slipper portion 20a of the rocker arm 20 is in contact with the cam 18.

The rocker arm 20 is swingably supported by the rocker arm shaft 10 held by the cylinder head 6.

In the cylinder block 4, a block-side oil passage 22 for guiding lubricating oil pumped by driving of an oil pump (not shown) is formed so as to be vertically oriented.

As is apparent from FIGS. 1 to 3, the cylinder head 6 has an oil rising passage 24 having a circular cross section and having one end communicating with the block-side oil passage 22 and pointing upward from the internal combustion engine 2. I have. A cylindrical oil jet 26 is interposed at the other end, which is the upper end of the oil rising passage 24.

2, the other end of the oil rising passage 24 communicates with a main oil passage 28 having a circular cross section.

As shown in FIG. 3, the main oil passage 28 is oriented in the axial direction of the camshaft 8 of the internal combustion engine 2 and is provided with a first main oil passage 28- 1 and the second drilled from the other end face 6d-2 of the cylinder head 6
And a main oil passage 28-2.

The oil rising passage 24 is provided in the main oil passage 28.
Through the inner peripheral surface of the main oil passage 28 and the outlet end portion of the oil rising passage 24 that comes into contact with the inner peripheral surface.
Is configured.

More specifically, as shown in FIGS. 1 and 2, an outlet end portion at the other end of the oil rising passage 24, for example, an upper end portion 24 is provided.
a into the main oil passage 28, as shown in FIG.
The inner peripheral surface 28s of the main oil passage 28 is brought into contact with two portions of the upper end portion 24a of the oil rising passage 24, and the inner peripheral surface 28s of the main oil passage 28 and the upper end portion 24a of the oil rising passage 24 and the upper end of the oil jet 26 are contacted. The aperture section 30 having an aperture function
Is formed.

One end of the first main oil passage 28-1 is closed by a blind plug 32, and the other end of the second main oil passage 28-2 is closed by a blind plug 34.

The first main oil passage 28-1 is provided with oil distribution passages 38-1 and 38- that guide lubricating oil toward the journal 36 of the camshaft 8.
2, 38-3 are in communication. This oil distribution passage 38
It communicates with a camshaft oil hole (not shown) formed in the camshaft 8 and a journal 36.

A rocker arm shaft is provided in the second main oil passage 28-2.
Oil distribution passages 38-4 and 38-5 for leading the lubricating oil to the 10 side communicate with each other. The oil distribution passage 38-5 is provided on the rocker arm shaft.
It communicates with a rocker arm shaft oil hole 40 formed at 10.

 Next, the operation of this embodiment will be described.

When the internal combustion engine 2 is operated and an oil pump (not shown) is driven, the lubricating oil from the block-side oil passage 22
The oil is supplied to the camshaft 8 and the rocker arm shaft 10 through the oil rising passage 24, the main oil passage 28, and the oil distribution passages 38, thereby lubricating the moving parts of the camshaft 8, the rocker arm shaft 10, and other components. Can be applied.

Next, when the internal combustion engine 2 is stopped, the driving of the oil pump is stopped and the pumping of the lubricating oil is stopped, but the upper end portion 24a of the oil rising passage 24 in the main oil passage 28 is inserted into the main oil passage 28. The upper part 24a of the main oil passage 28 and the upper end part 24a of the oil rise passage 24 and the oil jet 26 Since the throttle portion 30 is formed by the upper end, as shown in FIG. 1, lubricating oil at a position lower than the throttle portion 30 remains in the first and second main oil passages 28-1 and 28-2. It will be.

When the internal combustion engine 2 is restarted, the first and second lubricating oils are supplied from the block-side oil passage 22 side.
Since the lubricating oil remaining in the main oil passages 28-1 and 28-2 is quickly moved from the oil distribution passage 38 to the cam shaft 8 and the rocker arm shaft 10, the lubricating oil is supplied to the cam shaft 8 and the rocker arm shaft 10. The lubrication of the sliding surfaces of the moving parts of the cam shaft 8, the cam journal portion 36 and the rocker arm shaft 10 side is surely performed, and the occurrence of wear and seizure is prevented. The durability of each component can be improved.

Also, by forming the constricted portion 30 at the upper end portion 24a of the oil rising passage 24, the oil jet 26 provided at the upper end portion 24a of the oil rising passage 24 becomes one step as shown in FIGS. Only the processing is required, the production of the oil jet 26 becomes easy, the cost can be reduced, and it is economically advantageous.

Furthermore, even when a hydraulic lash adjuster (not shown) is provided in communication with the main oil passage 28, air can be reliably prevented from entering the hydraulic lash adjuster, and the operation of the hydraulic lash adjuster is improved. And the occurrence of abnormal noise can be prevented.

Note that the present invention is not limited to the above embodiment, and various application modifications are possible.

For example, in the embodiment of the present invention, the outlet end portion of the oil rising passage is directed upward to be the upper end portion,
The inner peripheral surface of the main oil passage, the upper end portion of the oil rising passage and the upper end of the oil jet formed a throttle portion having a throttle function, but the outlet end portion of the oil rising passage was directed laterally or obliquely upward, It is also possible to form a throttle portion by the inner peripheral surface of the main oil passage, the outlet end portion of the oil rising passage, and the upper end of the oil jet.

[Effect of the Invention] As is apparent from the detailed description above, according to the invention, in the lubricating oil passage structure of the internal combustion engine, an oil jet is provided at the upper end side of the oil rising passage having a circular cross section, and the oil rising passage is provided. Into the main oil passage, and the throttle portion is formed by the inner peripheral surface of the main oil passage, the outlet end portion of the oil rising passage in contact with the inner peripheral surface, and the upper end of the oil jet, so that when the internal combustion engine is restarted, The remaining lubricating oil is instantaneously supplied to the camshaft side to achieve good lubrication, prevent the occurrence of friction and seizure of the moving parts of each part, and improve the durability of each part.

[Brief description of the drawings]

1 to 4 show an embodiment of the present invention. FIG. 1 is an enlarged sectional view of a main part of an arrow I portion of FIG. 3, FIG. 2 is an enlarged right side view of FIG. 1, and FIG. FIG. 4 is a schematic front view of a lubricating oil passage structure of the internal combustion engine. 5 to 10 show three embodiments of a conventional lubricating oil passage structure of an internal combustion engine, FIG. 5 is a schematic side view of a lubricating oil passage structure of an internal combustion engine of a first embodiment, and FIG. FIG. 7 is a schematic front view of a lubricating oil passage structure of the internal combustion engine,
FIG. 8 is a schematic side view of a lubricating oil passage structure of the internal combustion engine of the second embodiment, FIG. 9 is a schematic front view of a lubricating oil passage structure of the internal combustion engine,
FIG. 10 is a schematic side view of a lubricating oil passage structure of an internal combustion engine provided with a hydraulic lash adjuster according to a third embodiment. In the figure, 2 is an internal combustion engine, 4 is a cylinder block, 6
Is a cylinder head, 8 is a cam shaft, 10 is a rocker arm shaft,
12 is a cylinder head cover, 14 is a sealing material, 16 is a cam cap, 18 is a cam, 20 is a rocker arm, 20a is a slipper part, 22 is a block side oil passage, 24 is an oil rising passage, 26 is an oil jet, and 28 is a main oil. A passage, 30 is a throttle portion, 32 and 34 are blind plugs, 36 is a journal portion, 38 is an oil distribution passage, and 40 is a rocker arm shaft oil hole.

Claims (1)

(57) [Scope of request for utility model registration] An oil rising passage formed in a cylinder head for introducing lubricating oil from a cylinder block side of an internal combustion engine and a shaft of a camshaft connected to the oil rising passage and held by the cylinder head. A lubricating oil passage structure for an internal combustion engine having a main oil passage having a circular cross section directed in a direction, and a plurality of oil distribution passages for guiding lubricating oil from the main oil passage to each portion of the camshaft; An oil jet is interposed at the upper end of the oil jet passage, the oil rising passage enters the main oil passage, an inner peripheral surface of the main oil passage, an outlet end portion of the oil rising passage contacting the inner peripheral surface, and the oil jet. A lubricating oil passage structure for an internal combustion engine, wherein a throttle portion is formed by an upper end of the lubricating oil passage.