JPH0586828A - Oil filling port structure of engine - Google Patents

Abstract

PURPOSE:To improve the rigidity and sealing ability of a cam cap, and prevent oil fed into a cylinder head from leaking out to the outside. CONSTITUTION:There is provided a cam cap 20 which is integratedly-formed on the upper side around the front ends of two intake/exhaust cam shafts CS, and a cover member 9 for covering a cam pulley 7 where a timing belt 8 is engaged is fixed at the front surface side of the cam cap 20. Besides, the front end part of the cylinder head cover 3 is fixed on the rear surface side of the cam cap 20, and an oil filler passage 26 which extends in a vertical direction is integratedly-formed from a passage wall 29 which forms a reinforcement wall reinforcing the cam cap 20 between bearing storage parts 25L, 25R which receive the front end adjacent parts of both the intake/exhaust cam shafts CS of the cam cap 20.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an engine oil inlet structure, and more particularly to a DOHC engine oil inlet structure.

[0002]

2. Description of the Related Art In recent years, in automobile engines, 2
A DOHC engine equipped with a book intake / exhaust camshaft has been widely adopted to achieve high engine output. Normal,
In the DOHC engine, an integral cam cap is provided near the front ends of the two intake and exhaust cam shafts, and the front ends of the cam caps are fixed to the front end portions of both intake and exhaust cam shafts. A cover member that covers the winding member around which the belt or chain is wound is fixed, and the front end of the cylinder head cover is fixed to the rear surface side of the cam cap. Generally, the cam cap, the cover member, and the cylinder head cover are made of synthetic resin or aluminum for weight reduction. By disposing the cam cap in this way, it is possible to prevent the oil supplied to the cylinder head from leaking to the outside or the winding member side, and to prevent the bearing and the cylinder head formed in the lower part of the cam cap from The formed bearing portion constitutes a bearing that rotatably supports the vicinity of the front end portions of both intake and exhaust camshafts.
An oil inlet for injecting oil into the oil pan of the engine is generally formed in the cylinder head cover so as to face the cylinder head space.

[0003]

Since the cam cap is a relatively small component and made of synthetic resin or aluminum, it has a low rigidity and is easily vibrated by the vibration force transmitted to the cam cap when the engine is driven. There's a problem. Further, when the cam cap vibrates while the engine is driven, the sealing performance of the cam cap deteriorates, and there is a problem that oil supplied to the cylinder head leaks to the outside or leaks to the winding member side. Further, since the oil inlet is formed in the cylinder head cover so as to face the cylinder head space, there is a problem that the oil scattered by the rotation of the intake / exhaust cam shaft leaks out from the oil inlet.

An object of the present invention is to provide an oil inlet structure for an engine which improves the rigidity and sealability of the cam cap and prevents the oil supplied to the cylinder head from leaking to the outside. ..

[0005]

An oil inlet structure for an engine according to a first aspect of the present invention is an oil inlet structure for a DOHC engine, in which two intake and exhaust gas are provided on a cylinder head so as to extend in the front-rear direction. A cam cap that is integrally formed on the upper side near the front end of each of the intake and exhaust cam shafts, for which a winding member for winding a belt or a chain is fixed to the front end of the intake cam shaft, is provided. The bearing that supports the vicinity of the front end of the exhaust camshaft is composed of a bearing formed on the lower end of the cam cap and a bearing formed on the upper end of the cylinder head. A cover member for covering the winding member is fixed, and a front end portion of a cylinder head cover is fixed to a rear surface side of the cam cap, and a vertical direction is provided in a portion of the cam cap between the intake and exhaust cam bearings. Oil injection passage oil fill a passage its lower end is opened in the cylinder head cover at the upper end, forming an oil inlet extends is one that is integrally formed.

An engine oil inlet structure according to a second aspect of the present invention is the engine oil inlet structure according to the first aspect, wherein the front end portions of the two intake and exhaust camshafts are wound around by a timing belt. A cam pulley as a member is fixed, and the oil injection passage is formed on the rear surface side of the cam cap.

According to a third aspect of the present invention, there is provided an oil inlet structure for an engine according to the second aspect, wherein the engine is a V-type engine, and the vicinity of an upper portion of a cylinder head cover of both banks of the V-type engine. An intake manifold or a surge tank is installed in.

An engine oil inlet structure according to a fourth aspect of the present invention is the engine oil inlet structure according to the first or second aspects, wherein the oil inlet passage is extended to at least the upper end of the cover member. ..

According to a fifth aspect of the present invention, there is provided an oil inlet structure for an engine, wherein a passage wall forming the oil inlet passage is formed as a reinforcing wall for reinforcing the cam cap.

[0010]

In the oil inlet structure of the engine according to the first aspect, the oil injection passage is formed integrally with the cam cap between the intake and exhaust cam bearings. The rigidity of the cam cap is improved by the passage wall, and the vibration of the cam cap due to the vibration force transmitted to the cam cap when the engine is driven is reduced and the sealing performance of the cam cap is improved. Further, since the oil injection passage is formed to extend in the vertical direction, the oil injection port is separated from the intake / exhaust cam shaft, and the oil scattered by the rotation of the intake / exhaust cam shaft does not reach the oil injection port. It is possible to prevent the oil from leaking out from the oil inlet.

In the oil inlet structure of the engine according to the second aspect, basically the same effect as that of the first aspect can be obtained. In addition, since the oil injection passage is formed on the rear surface side of the cam cap, the oil injection passage and the winding member can be separated from each other, and the sealing performance of the cam cap can be further enhanced. Therefore, the timing belt can be prevented from being contaminated with oil, and the durability of the timing belt can be prevented from being deteriorated.

In the oil inlet structure of the engine according to the third aspect, basically the same effect as that of the second aspect can be obtained. In addition, in the V-type engine in which the intake manifold or the surge tank is installed above the left and right banks, the oil injection passage and the oil injection port are provided in the cam cap. The intake manifold or the surge tank can be compactly arranged near the upper part of the cylinder head cover without complicating the layout of the intake manifold or the surge tank.

In the oil inlet structure of the engine according to the fourth aspect, basically the same operation as that of the first or second aspect can be obtained. In addition, since the oil injection passage extends to at least the upper end of the cover member, the oil injection passage becomes long, and it is possible to reliably prevent the oil scattered by the rotation of the intake / exhaust cam shaft from reaching the oil injection port. Can be done.

In the oil inlet structure of the engine according to the fifth aspect, basically the same operation as the fourth aspect can be obtained. In addition, since the passage wall forming the oil injection passage is formed as the reinforcing wall that reinforces the cam cap, the rigidity of the cam cap can be further enhanced by effectively utilizing the passage wall, and the sealing performance of the cam cap can be improved. It can be further increased.

[0015]

According to the oil inlet structure of the engine of the present invention, the following effects can be obtained as described in the above section. According to the engine oil inlet structure of the first aspect, the oil inlet passage is integrally formed in the cam cap between the intake and exhaust cam bearings.
The rigidity of the cam cap is increased by the passage wall forming the oil injection passage, and the vibration of the cam cap due to the vibration force transmitted to the cam cap when the engine is driven can be reduced. Therefore, the sealing performance of the cam cap can be improved, and the oil can be prevented from leaking outside from the cylinder head or leaking to the winding member side. Further, since the oil injection passage is formed to extend in the vertical direction, the oil injection port is separated from the intake / exhaust cam shaft, and the oil scattered by the rotation of the intake / exhaust cam shaft does not reach the oil injection port. Without
It is possible to prevent the oil from leaking to the outside or the winding member side from the oil inlet.

In the engine oil inlet structure according to the second aspect, basically the same effect as that of the first aspect can be obtained. In addition, since the oil injection passage is formed on the rear surface side of the cam cap, the oil injection passage and the winding member can be separated from each other, and the sealing performance of the cam cap can be further enhanced. Therefore, the timing belt can be prevented from being contaminated with oil, and the durability of the timing belt can be prevented from being deteriorated.

In the engine oil inlet structure according to the third aspect, basically the same effect as that of the second aspect can be obtained. In addition, in the V-type engine in which the intake manifold or the surge tank is installed above the left and right banks, the oil injection passage and the oil injection port are provided in the cam cap. The intake manifold or the surge tank can be compactly arranged near the upper part of the cylinder head cover without complicating the layout of the intake manifold or the surge tank.

In the engine oil inlet structure according to the fourth aspect, basically the same effect as that of the first or second aspect can be obtained. In addition, since the oil injection passage extends to at least the upper end of the cover member, the oil injection passage becomes long, and it is possible to reliably prevent the oil scattered by the rotation of the intake / exhaust cam shaft from reaching the oil injection port. Can be done.

In the engine oil inlet structure according to the fifth aspect, basically the same effect as that of the fourth aspect can be obtained. In addition, since the passage wall forming the oil injection passage is formed as the reinforcing wall that reinforces the cam cap, the rigidity of the cam cap can be further enhanced by effectively utilizing the passage wall, and the sealing performance of the cam cap can be improved. It can be further increased.

[0020]

Embodiments of the present invention will be described below with reference to the drawings. In this embodiment, the present invention is applied to an oil inlet structure of a DOHC-V type 8 cylinder engine E (hereinafter referred to as engine). As shown in FIG. 1, a main intake pipe 1 extending from an air cleaner (not shown) is provided between the left and right banks BL and BR of the engine E, and a cylinder head 2 of both banks BL and BR (see FIG. 3), a cylinder head cover 3 made of synthetic resin is provided, and surge tanks 4 into which air is introduced from the main intake pipe 1 are arranged in the front-rear direction near the upper and lower cylinder head covers 3 respectively. In addition, an intake manifold 5 having one end connected to the surge tank 4 and the other end connected to the cylinder head 2 is provided. Air is supplied to each cylinder of the engine E by a pair of left and right intake manifolds 5. Reference numeral 6 is a communication pipe formed in communication with the intake manifold 5 on the outside. Figure 1
As shown in FIG. 2, two intake / exhaust cam shafts CS, which are provided on the cylinder heads 2 of the left and right banks BL and BR so as to extend in the front-rear direction, are integrally formed of aluminum on the upper side near the front ends. Cam caps 20 are provided respectively. On the front side of the left and right cam caps 20, the cam pulleys 7 fixed to the front end portions of the intake and exhaust cam shafts CS and the cam pulleys 7 are provided.
Synthetic resin cover members 9 for covering the timing belt 8 mounted on the left and right are respectively fixed, and front end portions of the left and right cylinder head covers 3 are fixed to rear surfaces of the left and right cam caps 20, respectively.

Next, the cam cap 20 and the oil inlet structure provided in the cam cap 20 will be described. Since the left and right cam caps 20 have substantially the same structure, the cam cap 20 of the right bank BR will be described and the left bank BL will be described.
The different points of the cam cap 20 will be described supplementarily. As shown in FIGS. 3 to 5, the cover portion 2 is provided on the upper end of the sheet-shaped cam cap body 21 of the cam cap 20.
2 is formed so as to project forward and is curved in the same shape as the upper end of the cover member 9, and a base portion 23 is formed at the lower end of the cam cap body 21 so as to project on both front and rear sides of the cam cap body 21. Cam shaft insertion holes 24 through which the intake and exhaust cam shafts CS are inserted are formed in the right and left portions of the base portion 23, respectively. The front end portions of the left and right cam shaft insertion holes 24 form bearing portions 25L and 25R for accommodating bearing members, and the left and right bearing portions formed corresponding to these bearing accommodating portions 25L and 25R and the front end portion of the cylinder head 2. A bearing that rotatably supports the portions near the front ends of both the intake and exhaust camshafts CS is formed. In FIG. 4, reference numerals 32 and 33 denote a flange portion formed in the cover portion 22 and a bolt hole formed in the flange portion, and the cover member 9 corresponds to the flange portion 32 and the bolt hole 33. It is assumed that the flange portion and the bolt hole are formed. Cam cap body 2
An oil injection passage 26 for injecting oil into an oil pan (not shown) is provided in a vertical direction in the rear portion of the base portion 23 on the rear side of the first portion between the left and right cam shaft insertion holes 24 and in the cover portion. 22 is formed so as to extend above 22. An upper end of the oil injection passage 26 forms an oil injection port 27, an oil cap 28 is screwed to the oil injection port 27, and a lower end of the oil injection passage 26 is inside the cylinder head cover 3. It is open. Further, the passage wall 29 forming the oil injection passage 26 is formed as a relatively thick wall, and forms a reinforcing wall for reinforcing the cam cap 10. The left bank B
The oil inlet of the L cam cap 10 is closed.

A receiving portion 3 for receiving the front end portion of the cylinder head cover 3 is provided at the upper edge of the rear end portion of the base portion 23.
0 is formed so as to project rearward and horizontally. Also,
Four bolt holes 31 are formed in the base portion 23, and a concave engagement concave portion 21a is formed on the front side in a portion of the rear surface of the cam cap body 21 corresponding to the bolt hole 31, respectively.
The flange portion 1 having a bolt hole corresponding to the bolt hole 31 of the base portion 23 at the front end portion of the cylinder head cover 3.
2 is formed. In FIG. 3, reference numeral 34 is a seal member mounted on the cylinder head cover 3.
The cylinder head cover 3 has a front end portion which is a base portion 23.
The receiving portion 30 of FIG.
As shown in FIG. 5, the cover member 9 is fixedly connected to the base portion 23 of the cam cap 20 by the bolt B, and the cover member 9 is disposed such that the upper end portion of the cover member 9 is in close contact with the cover portion 22 of the cam cap 20. Flange portion 3 of cap 20
2 and a corresponding flange portion of the cover member 9 are connected to the cam cap 20 by bolts, and a sealing material is applied to the mating surfaces of the cylinder head 2 and the cam cap 20.

Next, the operation of the oil inlet structure will be described. Of the rear portion of the base portion 23 on the rear surface side of the cam cap body 21, between the cam shaft insertion holes 24,
An oil injection passage 26 extending upward from the cover portion 22 of the cam cap body 21 is integrally formed in the vertical direction, and a passage wall 29 forming the oil injection passage 26 has a cam wall 2.
Since it is formed on the reinforcing wall that reinforces 0, the passage wall 29
The rigidity of the cam cap 20 can be enhanced by effectively utilizing the above, and the cam cap 20 does not vibrate due to the vibration force transmitted to the cam cap 20 when the engine E is driven. Therefore, the sealing performance of the cam cap 20 can be improved, and the oil can be prevented from leaking outside from the cylinder head 3 or leaking to the cam pulley 7 side. Further, since the oil injection port 28 is separated from the intake / exhaust cam shaft CS, the oil scattered by the rotation of the intake / exhaust cam shaft CS does not reach the oil injection port 28, and the oil flows from the oil injection port 28 to the outside. It is possible to prevent the oil from leaking to the cam pulley 7 side. Therefore, it is possible to reliably prevent the timing belt from being contaminated with oil, and it is possible to prevent the durability of the timing belt from decreasing. In addition, in the V-type engine E in which the surge tank 4 and the intake manifold 5 are provided above the left and right banks BL and BR, the oil injection passage 26 and the oil injection port 28 are provided in the cam cap 20. The surge tank 4 and the intake manifold 5 can be compactly arranged in the vicinity of the upper portion of the cylinder head cover 3 without complicating the layout of the surge tank 4 and the intake manifold 5 to arrange them. The oil inlet structure may be provided in the left bank BL. Further, the cylinder head cover 3, the cover member 9, and the cam cap 20 made of aluminum may be used instead of the synthetic resin. Further, instead of the cam pulley 7 and the timing belt 8, it is possible to use a sprocket and a chain. Of course, the oil inlet structure is not limited to the V-type engine, but can be applied to an in-line type engine or a horizontally opposed type engine.

[Brief description of drawings]

FIG. 1 is a partial plan view of an engine.

FIG. 2 is a partial plan view of an essential part of a right bank of an engine.

FIG. 3 is a sectional view taken along line 3-3 of FIG.

FIG. 4 is a rear view of the cam cap.

FIG. 5 is a bottom view of the cam cap.

[Explanation of symbols]

 CS camshaft for intake / exhaust E engine 3 cylinder head cover 4 surge tank 5 intake manifold 7 cam pulley 8 timing belt 9 cover member 20 cam cap 25L / 25R bearing housing 26 oil injection passage 27 oil injection inlet 29 passage wall

Claims (5)

[Claims] 1. A DOHC engine oil inlet structure comprising two intake and exhaust camshafts provided on a cylinder head so as to extend in the front-rear direction, and a belt or a chain wound around a front end of the camshaft. A cam cap that is integrally formed near the front ends of the two intake and exhaust cam shafts to which the respective members are fixed is provided, and the bearings that support the vicinity of the front ends of the two intake and exhaust cam shafts are It is composed of a bearing portion formed at the lower end portion and a bearing portion formed at the upper end portion of the cylinder head, and a cover member that covers the winding member is fixed to the front side of the cam cap, and the rear side of the cam cap The front end of the cylinder head cover is fixed, and a portion of the cam cap between the cam bearings for intake and exhaust that extends vertically is an oil injection passage whose lower end is the cylinder head cover. Oil inlet structure for an engine that its upper end is open into the over, characterized in that the oil injection passage forming an oil inlet are integrally formed. 2. A cam pulley as a winding member driven by a timing belt is fixed to the front ends of the two intake and exhaust cam shafts, and the oil injection passage is formed on the rear surface side of the cam cap. The oil inlet structure for an engine according to claim 1, wherein 3. The engine according to claim 2, wherein the engine is a V-type engine, and an intake manifold or a surge tank is arranged near upper portions of cylinder head covers of both banks of the V-type engine. Oil inlet structure. 4. The oil inlet structure for an engine according to claim 1, wherein the oil inlet passage extends at least to an upper end of the cover member. 5. The engine oil inlet structure according to claim 4, wherein a passage wall forming the oil inlet passage is formed as a reinforcing wall for reinforcing the cam cap.