JP2000337122A - Oil pressure supplying device for valve timing control type internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To aim at the miniaturization and reduction of weight while supplying the lubricating oil to an oil pressure control valve inside of an internal combustion engine provided with the oil pressure control valve in relation to a hydraulic valve timing variable device in a bearing cap body for pivotally supporting a cam shaft on a cylinder head and provided with a lubricating oil passage for supplying the lubricating oil from a lubricating oil pump to the bearing part of the cam shaft. SOLUTION: A branch passage 23 divided from a lubricating oil passage 22 and opened in the top surface of a cylinder head is formed inside of a cylinder head 2, and an oil pressure passage 24 for communicating the branch passage 23 with a supply port 16c to an oil pressure control valve 16 is formed inside of a bearing cap body 7. Furthermore, an orifice body 25 provided with an orifice 25b for regulating flow of the lubricating oil to the upstream side of the lubricating oil passage 24 at a little quantity is inserted into the branch passage 23.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an internal combustion engine provided with a valve timing control device for changing a valve timing for opening and closing an intake valve and an exhaust valve in accordance with an operation state. And a device for supplying hydraulic pressure to the device.

[0002]

2. Description of the Related Art Generally, an internal combustion engine provided with a valve timing control device for changing a valve timing for opening and closing an intake valve and an exhaust valve in accordance with an operation state is described in Japanese Patent Application Laid-Open No. 10-317925 as a prior art. Have been.

In an internal combustion engine equipped with this valve timing control device, one of an intake valve camshaft and an exhaust valve camshaft is provided with a power transmission wheel (timing pulley or timing chain) by rotating the crankshaft. And input via
The camshaft is configured to transmit rotation from the one camshaft to the other camshaft, and further, between the one camshaft and its power transmission wheel, the valve timing is advanced or retarded by supplying hydraulic pressure, While providing a hydraulic type variable valve timing device that retards or advances valve timing by eliminating hydraulic pressure, a hydraulic control valve is provided in a hydraulic supply path for supplying lubricating oil in the internal combustion engine to the variable valve timing device. The supply and discharge of the lubricating oil pressure to the variable valve timing device are controlled by the hydraulic control valve according to the operating state of the internal combustion engine.

[0004]

In this type of valve timing control type internal combustion engine, in order to ensure the operation response of the variable valve timing device, the internal combustion engine is supplied to a hydraulic control valve for the variable valve timing device. Therefore, the valve timing control type internal combustion engine of the prior art described above requires the supply of the lubricating oil from the lubricating oil pump to the hydraulic control valve by each of the lubricating oil pumps. The lubricating oil supply path to the camshaft is different from the supply path, and the lubricating oil is supplied through a hydraulic line disposed outside the internal combustion engine.

[0005] For this reason, in the prior art, the number of parts is increased, the weight is increased and the price is increased. In addition, the leakage of the lubricating oil is liable to occur, and the hydraulic piping is damaged. There was a problem that there was a great risk.

The present invention solves this problem under the condition that a sufficient amount of lubricating oil is supplied to the variable valve timing device by utilizing a cam shaft lubricating oil supply passage provided in the cylinder head. It is a technical task to solve the problem.

[0007]

SUMMARY OF THE INVENTION In order to achieve the above technical object, the present invention provides a method of connecting an intake valve cam shaft and an exhaust valve cam shaft to an upper surface of a cylinder head. The rotation of the crankshaft is input to one of the camshafts via a power transmission wheel, and the rotation is transmitted from one camshaft to the other camshaft. On the other hand, a hydraulic valve timing variable device is provided between the one camshaft and its power transmission wheel, and a hydraulic control valve for the valve timing variable device is provided on the bearing cap body. In an internal combustion engine having a lubricating oil passage for supplying lubricating oil from a lubricating oil pump to a bearing portion of the camshaft inside a cylinder head, the lubricating oil for the camshaft is provided inside the cylinder head. A branch passage that branches off from a passage and opens on the upper surface of the cylinder head, and a hydraulic passage that communicates the branch passage and a supply port to the hydraulic control valve is formed inside the bearing cap body; In the branch passage, an orifice body having an orifice for regulating the flow rate from the branch passage to the upstream side of the lubricating oil passage to a small amount is inserted. "

[0008]

In this configuration, the lubricating oil from the lubricating oil pump once flows into the branch passage from the lubricating oil passage, and from this branch passage, the hydraulic pressure for the bearing of the camshaft and the variable valve timing device is transmitted. It is distributed to the control valve.

In this case, the amount of lubricating oil supplied to the bearing portion of the camshaft can be regulated to the minimum amount necessary for lubrication at the orifice of the orifice body inserted into the branch passage. A sufficient amount of lubricating oil can be supplied to the hydraulic control valve for the variable valve timing device without increasing the capacity of the oil pump.

According to the present invention, a sufficient amount of lubricating oil can be supplied to the variable valve timing device by using the lubricating oil passage for the camshaft formed inside the internal combustion engine. From the problem that the prior art has, the cylinder head is formed with a branch passage communicating with the lubricating oil passage to the camshaft, and the bearing cap body is formed with a hydraulic passage from this branch passage to the hydraulic control valve. This has the effect of being eliminated with a very simple structure of inserting an orifice body into the branch passage.

According to the second aspect of the present invention, it is possible to provide an oil filter in the hydraulic passage to the hydraulic control valve for the variable valve timing device without increasing the size with a simple structure. Has effects that can be achieved.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.

In this drawing, reference numeral 1 denotes a cylinder block, and reference numeral 2 denotes a cylinder head fastened to the upper surface of the cylinder block 1, and a cam shaft 3 for an intake valve is provided on the upper surface of the cylinder head 2. And the camshaft 4 for the exhaust valve are arranged in parallel.
Bearing parts 5, 6 provided integrally with the cylinder head 2,
A plurality of bearings are rotatably supported on the upper surface of the cylinder head 2 by a bearing cap 7 which is fastened to a plurality of bolts 8.

A timing pulley 9 is fitted to a portion of the exhaust valve camshaft 4 protruding outside the bearing cap body 7, and a timing from the crankshaft (not shown) is attached to the timing pulley 9. By rotating the belt 10, the rotation of the crankshaft is transmitted to the exhaust valve camshaft 4, and the rotation of the exhaust valve camshaft 4 is transmitted to the intake valve 11 by a pair of gears 11 and 12 meshing with each other. The transmission is transmitted to the valve camshaft 3.

Reference numeral 13 denotes a cover for covering the timing pulley 9 and the timing belt 10;
Indicates a head cover that covers the upper surface of the cylinder head 2.

Gear 11 on cam shaft 4 for exhaust valve
For example, in a portion between the motor and the timing pulley 10, for example, JP-A-10-196324 or JP-A-10-196324.
There is provided a hydraulic valve timing variable device 15 described in Japanese Patent No. 317925 and the like. By supplying hydraulic pressure to the valve timing variable device 15, at least the valve timing of the intake valve is advanced or retarded, and the hydraulic pressure is controlled. By the elimination, at least the valve timing of the intake valve is configured to be retarded or advanced.

On the upper surface of the bearing cap 7, a valve case 16a and a valve 16b inserted therein are provided.
And a hydraulic control valve 16 composed of
6 is an actuator 17 related to the operating state of the internal combustion engine.
A state in which the hydraulic pressure at the hydraulic pressure supply port 16c is supplied to the variable valve timing device 15 through a passage 18 formed inside the bearing cap body 7 and a passage 19 formed inside the camshaft 4; A passage 20 formed inside the camshaft 4 and a passage 21 formed inside the bearing cap 7 in the variable device 15.
Is configured to be switched to a release state via a.

Further, inside the cylinder head 2, lubricating oil sent from a lubricating oil pump (not shown) on the cylinder block 1 side is supplied to the bearing portion 5 of the cam shaft 3 for the intake valve. Lubricating oil passage 22 for supply
Are formed.

A branch passage 23 having one end communicating with the lubricating oil passage is formed inside the cylinder head 2.
The other end of the branch passage 23 is drilled so as to open to the upper surface of the cylinder head 2, while the branch passage 23 communicates with the hydraulic supply port 16 c of the hydraulic control valve 16 inside the bearing cap 7. A hydraulic passage 24 is formed.

Further, a pipe-shaped orifice 25 is inserted into the branch passage 23, and the orifice 25 has a large orifice D having a large inner diameter D which opens in the lubricating oil passage 22 downstream of the branch passage 23. 25a and an orifice 25b having a small inner diameter d which opens in the lubricating oil passage 22 on the upstream side of the branch passage 23, while a bearing cap of a hydraulic passage 24 formed inside the bearing cap body 7 is provided. An oil filter 26 is removably inserted into a portion opening to the lower surface of the body 7.

The oil filter 26 is supported by a support 27 fitted over both the cylinder block 1 and the cylinder head 2 as shown in FIG. A configuration in which two O-rings 28 and 29 for sealing are fitted to the outer periphery, or FIG.
As shown in (1), the support may be supported by a support 30 fitted on the cylinder head 2 side, and an O-ring 31 for sealing may be fitted on the support 30.

In this configuration, the lubricating oil from the lubricating oil pump on the cylinder block 1 side is supplied to the lubricating oil passage 22.
From the branch passage 23, and is distributed from the branch passage 23 to the bearing portion 5 of the camshaft 3 and the hydraulic control valve 16 for the variable valve timing device 15.

In this case, the amount of lubricating oil supplied to the bearing portion 5 of the camshaft 3 is restricted to the minimum amount necessary for lubrication at the small diameter d orifice in the orifice body 25 inserted into the branch passage 23. Therefore, a sufficient amount of lubricating oil can be supplied to the hydraulic control valve 16 for the variable valve timing device 15.

In the above embodiment, the hydraulic passage to the hydraulic control valve for the variable valve timing device is branched from the lubricating oil passage 23 to the bearing portion 5 of the intake valve cam shaft 3. The lubricating oil supplied to the bearing portion 5 of the intake valve camshaft 3 may be configured so as to branch from a lubricating oil passage to the bearing portion 6 of the exhaust valve camshaft 4. Is supplied to the other bearings of the camshaft 3 through the inside of the camshaft 3 so as to be supplied from the intake valve camshaft 3 to each bearing of the exhaust valve camshaft 4. It is needless to say that the present invention can be applied to the case in which

[Brief description of the drawings]

FIG. 1 is a plan view showing an embodiment of the present invention,
It is I sectional drawing.

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

FIG. 3 is a sectional view taken along line III-III in FIG.

FIG. 4 is an enlarged view of a main part of FIG. 3;

FIG. 5 is a diagram showing a modification of FIG. 4;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Cylinder block 2 Cylinder head 3 Camshaft for intake valve 4 Camshaft for exhaust valve 5, 6 Bearing part 7 Bearing cap body 8 Bolt 9 Timing pulley (power transmission wheel) 10 Timing belt 11, 12 Gear 15 Valve variable device 16 Hydraulic control valve 16c Hydraulic control valve hydraulic supply port 22 Lubricating oil passage 23 Branch passage 24 Hydraulic passage 25 Orifice body 25b Small diameter orifice 26 Oil filter

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) F02F 1/24 F02F 1/24 RF Term (Reference) 3G013 AA06 AA07 BC20 BD11 BD12 BD14 BD38 BD41 CA05 3G016 AA02 AA08 AA12 AA19 BA22 BA28 BA50 CA23 CA24 DA06 GA01 3G024 AA05 AA19 BA23 DA03 DA10 DA18 FA07 FA13 GA11

Claims (2)

[Claims] An intake valve camshaft and an exhaust valve camshaft are supported on an upper surface of a cylinder head by a bearing cap body fastened to the cylinder head, and one of the two camshafts is provided. The rotation of the crankshaft is input to the shaft via a power transmission wheel, and the rotation is transmitted from the one camshaft to the other camshaft. In addition, a hydraulic valve timing variable device,
A hydraulic control valve for the variable valve timing device is provided on the bearing cap body, and a lubricating oil passage for supplying lubricating oil from a lubricating oil pump to a bearing portion of the camshaft is provided inside the cylinder head. In the internal combustion engine, a branch passage branching from a lubricating oil passage to the camshaft and opening to the upper surface of the cylinder head is provided inside the cylinder head, and the branch passage and the hydraulic pressure are provided inside the bearing cap body. An orifice body that forms a hydraulic passage communicating with a supply port to a control valve, and further includes an orifice in the branch passage that regulates a small amount of flow from the branch passage to the upstream side of the lubricating oil passage. A hydraulic pressure supply device for a valve timing control type internal combustion engine, wherein 2. The valve timing control system according to claim 1, wherein an oil filter is removably inserted into a portion of the hydraulic passage in the bearing cap body that opens to the lower surface of the bearing cap body. A hydraulic pressure supply device for an internal combustion engine.