JP2001349416A - Chain guide - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize a chain guide capable of effectively regulating vibration of a timing chain. SOLUTION: The chain guide for regulating a timing chain has an oil passage for supplying oil from an oil pump to a cylinder head. The oil passage has a head side oil passage disposed in a timing chain chamber in a cylinder head cover, and the head side oil passage is made of pipe member. One side of the chain guide is fixed to the cylinder head, and the other side is connected to the pipe member. A hydraulic actuator is added that changes rotation phase between one of an intake cam sprocket and an exhaust cam sprocket that are hung with the timing chain and a camshaft mounted with the sprocket.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chain guide and, more particularly, to a chain guide for effectively controlling timing chain vibration.

[0002]

2. Description of the Related Art An engine mounted on a vehicle or the like transmits a driving force from a crankshaft to an intake camshaft and an exhaust camshaft via a timing chain.

At this time, the timing chain is maintained in an appropriate tension state by the pressing force from the tensioner.

As a chain guide, Japanese Utility Model Laid-Open No. 3-77 is used.
No. 839 is disclosed. The chain guide disclosed in this publication has a guide piece that contacts and guides a chain, and a mounting piece that is mounted on an installation surface orthogonally to the guide piece, and the guide piece and the mounting piece that is separated from the installation surface. Are formed on at least one of them.

[0005]

In a conventional engine, as shown in FIGS. 10 and 11, a crankshaft (not shown) is supported at a lower portion of a cylinder block 204 of an engine 202, and is provided at an upper portion of the cylinder block 204. Attach the cylinder head 206 to the cylinder head 20
An intake camshaft 212 for opening and closing an intake valve (not shown) and an exhaust camshaft 214 for opening and closing an exhaust valve (not shown) are rotatably supported by a cam housing 216 at the upper part of the cylinder head 206. Attach intake and exhaust manifolds (not shown) to the side and the other side.
The head cover 208 is attached to 06 so as to cover the intake and exhaust cam shafts 212 and 214.

[0006] A crank sprocket (not shown) is attached to one end of the crankshaft.
An exhaust cam sprocket 220 is attached to one end of the exhaust cam shaft 214 while an intake cam sprocket 218 is attached to one end of the exhaust cam shaft 218.

[0007] The crank sprocket and the suction
A timing chain 222 is wound around the exhaust cam sprockets 218 and 220, and the rotation of the crankshaft is absorbed and exhausted by the timing chain 222.
12, 214.

The engine 202 is provided with a chain cover 210 attached to one end in the longitudinal direction of the cylinder block 204 and the cylinder head 206 so as to cover the timing chain 222.
To form

In the engine 202, a crank pulley (not shown) is mounted on the crankshaft so as to be located immediately in front of the front of the chain cover 210, and a plurality of auxiliary devices such as a water pump and an alternator driven by the crankshaft are provided. ing.

The engine 202 is provided with an oil pump 226 driven by a crankshaft. The oil pump 226 includes an inner rotor and an outer rotor (not shown) rotatably built in a pump housing 228 provided on the chain cover 210. The inner rotor and the outer rotor are rotated by a crankshaft, and an oil pan The oil inside is sucked, compressed and discharged.

The oil discharged from the oil pump 226 is filtered by an oil filter (not shown) and supplied to a main gallery 230 which is directed in the axial direction of the crankshaft of the cylinder block 204. The oil in the main gallery 230 is supplied to the crankshaft and the intake / exhaust camshaft 21.
2, 214, are supplied to valve operating systems such as intake and exhaust valves and auxiliary systems such as water pumps.

The engine 202 is provided with a hydraulic variable valve timing (“VVT”) device 232. The variable valve timing device 232 is provided with a hydraulic actuator 234 that changes the rotation phase of, for example, the intake cam sprocket 218 and the intake cam shaft 212 to which the intake cam sprocket 218 is attached. The hydraulic actuator 234 is discharged from an oil pump. Oil is supplied via an oil control valve 236. The hydraulic actuator 234 is attached to one end of the intake camshaft 212, and the oil control valve 236 is attached to the front of the chain cover 210.

The oil control valve 236 includes a substantially cylindrical valve body 238 for supplying oil to the hydraulic actuator 234 and a substantially cylindrical solenoid 240 for operating the valve body 238. The solenoid unit 240 is provided integrally and continuously in the longitudinal direction. The valve body 238 incorporates a spool valve (not shown) and has a mounting flange 242. The solenoid 240 has a built-in solenoid coil (not shown) and is connected to a cable (not shown).

The oil control valve 23
6 is a mounting bolt 24 provided on a valve mounting boss 244 provided with a mounting flange 242 on the front surface of the chain cover 210.
Attach with 6. The valve mounting boss 244 is provided above the front surface of the chain cover 210, and the oil control valve 236 is attached to a substantially central portion of the chain cover 210 so as to straddle the joint surface P between the cylinder head 206 and the cylinder block 204. One end attached to the valve attachment boss 244 is directed obliquely upward, and the other end is arranged close to the water pump pulley.

A mount mounting boss 248 is provided on the front surface of the chain cover 210 above the valve mounting boss 244, and the mount mounting boss 248 is provided.
Is mounted with an engine mount for supporting the engine 2 on a vehicle body (not shown).

The main gallery 230, into which the oil discharged from the oil pump 226 flows, has one end in the axial direction of the crankshaft connected to the cover communication hole 25 of the chain cover 210.
0 is provided in communication. The cover communication hole 250 is connected to the oil control valve 236 by the oil pipe 252.
The oil control valve 236 is
The oil taken in by the oil pipe 252 is distributed and supplied to the advance oil passage 254 and the retard oil passage 256 provided in the chain cover 210 as the advance oil and the retard oil.

The advancing oil passage 254 and the retarding oil passage 256 communicate with the advancing oil pipe 258 and the retarding oil pipe 260, which are pipe members, at the upper end of the chain cover 210. And the oil pipe 260 for the retard angle is connected to the cam housing 214.
Are connected to a housing advance oil passage and a housing retard oil passage 262, which are head side oil passages (not shown). The housing advance oil passage and the housing retard oil passage 262 communicate with the hydraulic actuator 234 via a camshaft advance oil passage and a camshaft retard oil passage (not shown) provided in the intake camshaft 212. ing.

The variable valve timing device 2
An oil control valve 32 controls the operation of an oil control valve 236 in accordance with the operation state of the engine 2 by control means (not shown), and distributes oil discharged from an oil pump 226 into advance oil and retard oil.
34, the intake cam sprocket 218 and the intake camshaft 2 to which the intake cam sprocket 218 is attached.
The valve timing of the intake / exhaust valve is varied by changing the rotation phase of the intake / exhaust valve 12.

However, when the intake camshaft and the exhaust camshaft are suddenly advanced and retarded, the timing chain 22
2 vibrates up and down in the free span portion S.

As a result, the meshing state of the timing chain with the intake cam sprocket and the exhaust cam sprocket becomes inaccurate, which causes vibration and noise, promotes abrasion, shortens the service life, and is economically disadvantageous. There are inconveniences.

In order to improve such a problem, the intake cam sprocket 318 and the exhaust cam sprocket 320
There is also a measure to provide a chain guide 364 at the timing chain 322 between the two.

At this time, the chain guide 364 is
As shown in FIG. 2 and FIG.
In a cantilevered support structure fixed by a fixing bolt 366.

However, as is apparent from FIG. 13, since the distance L between the timing chain 322 and the fixing bolt 366 is long, the chain guide 3 having a cantilever support structure is provided.
64 has insufficient strength, and there is a disadvantage that the vibration of the timing chain 322 cannot be effectively suppressed by the chain guide 364 having the cantilever support structure.

[0024]

SUMMARY OF THE INVENTION Accordingly, the present invention provides a cam sprocket provided on a cam shaft which is supported by an engine cylinder head in order to eliminate the above-mentioned disadvantages.
An oil passage that supplies oil discharged from an oil pump to a cylinder head in a chain guide that communicates with a crank sprocket provided on a crankshaft that is supported by a cylinder block via a timing chain and regulates the timing chain. The oil passage includes a head-side oil passage provided in a timing chain chamber in a cylinder head cover, and the head-side oil passage is formed by a pipe member, and the chain guide has one side fixed to the cylinder head. And the other side is connected to the pipe member.

Further, a cam sprocket provided on a cam shaft supported by a cylinder head of the engine and a crank sprocket provided on a crank shaft supported by a cylinder block are connected via a timing chain.
In a chain guide that regulates the timing chain, a hydraulic actuator that changes the rotational phase of one of an intake cam sprocket and an exhaust cam sprocket around which the timing chain is wound and a cam shaft to which the sprocket is attached is provided. An oil passage for supplying oil discharged from an oil pump to the hydraulic actuator, wherein the oil passage includes a head-side oil passage provided in a timing chain chamber in a cylinder head cover; Is formed by a pipe member, and the chain guide has one side fixed to the cylinder head and the other side connected to the pipe member.

[0026]

BEST MODE FOR CARRYING OUT THE INVENTION
When driving the engine, one side is fixed to the cylinder head, the other side is connected to the pipe member, and a chain guide that has improved strength as a state of both ends support structure,
The vibration of the timing chain is effectively controlled, the meshing state between the timing chain and the cam sprocket is made accurate, and noise and wear are reduced.

Further, even when one of the sprockets is suddenly phase-advanced or retarded by the hydraulic actuator, the timing chain at the portion where the loosening occurs most is regulated.

[0028]

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

FIGS. 1 to 4 show a first embodiment of the present invention. 2 to 4, reference numeral 2 denotes an engine mounted on a vehicle (not shown), 4 denotes a cylinder block, 6
Is a cylinder head, 8 is a head cover, and 10 is a chain cover.

As shown in FIGS. 2 and 3, the engine 2 supports a crankshaft (not shown) below the cylinder block 4. Further, the engine 2 has a cylinder head 6 mounted on an upper part of the cylinder block 4, and an opening / closing drive of an intake camshaft 12 and an exhaust valve (not shown) for opening and closing an intake valve (not shown) above the cylinder head 6. An exhaust cam shaft 14 is supported by a cam housing 16;
One side and the other side of the cylinder head 6
An exhaust manifold is installed, and the cylinder head 6
The head cover 8 is provided so as to cover the exhaust cam shafts 12 and 14.
Attach.

A crank sprocket (not shown) is attached to one end of the crankshaft. An intake cam sprocket 18 is attached to one end of the intake cam shaft 12, and an exhaust cam sprocket 20 is attached to one end of the exhaust cam shaft 14.

The crank sprocket and the suction sprocket
A timing chain 22 is wound around the exhaust cam sprockets 18 and 20, and the rotation of the crankshaft is absorbed and exhausted by the timing chain 22.
To communicate.

The engine 2 has a cylinder block 4
The chain cover 10 is attached to one end of the cylinder head 6 in the longitudinal direction so as to cover the timing chain 22 to form a timing chain chamber 24.

The engine 2 has a crank pulley (not shown) attached to a crankshaft so as to be located immediately before the front of the chain cover 10. Further, the engine 2 is provided with a plurality of accessories such as a water pump and an alternator driven by a crankshaft.

The engine 2 is provided with an oil pump 26 driven by a crankshaft, as shown in FIGS. The oil pump 26 includes a pump housing 28 provided on the chain cover 10 and a rotatable internal rotor and an outer rotor (not shown). The inner rotor and the outer rotor are rotated by a crankshaft. The oil inside is sucked, compressed and discharged.

The oil discharged from the oil pump 26 is filtered by an oil filter (not shown) and supplied to a main gallery 30 which is directed in the axial direction of the crankshaft of the cylinder block 4. The oil in the main gallery 30 is supplied to crankshafts, intake and exhaust camshafts 12 and 14, valve operating systems such as intake and exhaust valves, and auxiliary systems such as water pumps.

The engine 2 is provided with a hydraulic variable valve timing ("VVT") device 32, as shown in FIG. The variable valve timing device 32 is provided with a hydraulic actuator 34 for changing the rotation phase of, for example, the intake cam sprocket 18 and the intake camshaft 12 to which the intake cam sprocket 18 is attached, and the hydraulic actuator 34 is discharged from an oil pump. Oil is supplied via an oil control valve 36.
The hydraulic actuator 34 is attached to one end of the intake camshaft 12 and the oil control valve 3
6 is attached to the front surface of the chain cover 10.

The oil control valve 36 has a substantially cylindrical valve body 38 for supplying oil to the hydraulic actuator 34 and a substantially cylindrical solenoid 40 for operating the valve body 38.
And the solenoid portion 40 are provided integrally and continuously in the longitudinal direction. The valve body 38 incorporates a spool valve (not shown) and has a mounting flange 42. The solenoid unit 40 has a built-in solenoid coil (not shown) and is connected to a cable (not shown).

The oil control valve 36 has a mounting flange 42 mounted on a valve mounting boss 44 provided on the front surface of the chain cover 10 by a mounting bolt 46.
The valve mounting boss 44 is provided above the front surface of the chain cover 10, and the oil control valve 36 is attached to a substantially central portion of the chain cover 10 so as to straddle the joint surface P between the cylinder head 6 and the cylinder block 4. One end attached to the valve attachment boss 44 is directed obliquely upward, and the other end is arranged close to the water pump pulley.

A mount mounting boss 48 is provided on the front surface of the chain cover 10 above the valve mounting boss 44. An engine mount for supporting the engine 2 on a vehicle body (not shown) is mounted on the mount mounting boss portion 48.

The main gallery 30 into which the oil discharged from the oil pump 26 flows has one end in the axial direction of the crankshaft communicated with the cover communication hole 50 of the chain cover 10. The cover communication hole 50 is
2 is provided in communication with the oil control valve 36. The oil control valve 36 is connected to the oil pipe 5
The oil taken in step 2 is distributed and supplied to the advance oil passage 54 and the retard oil passage 56 provided in the chain cover 10 as the advance oil and the retard oil.

The advancing oil passage 54 and the retarding oil passage 56 are connected to an advancing oil pipe 58 and a retarding oil pipe 60 which are pipe members at the upper end of the chain cover 10. The advancing oil pipe 58 and the retarding oil pipe 60 communicate with a housing advancing oil passage and a housing retarding oil passage 62 which are head-side oil passages (not shown) of the cam housing 14. The housing advance oil passage and the housing retard oil passage 62 communicate with the hydraulic actuator 34 via a cam shaft advance oil passage and a cam shaft retard oil passage (not shown) provided in the intake camshaft 12. ing.

The variable valve timing device 32 controls the operation of an oil control valve 36 in accordance with the operating state of the engine 2 by control means (not shown), and converts the oil discharged from the oil pump 26 into advance oil and retard oil. The intake cam sprocket 18 and the intake cam shaft 12 to which the intake cam sprocket 18 is attached are changed in rotation phase to vary the valve timing of the intake and exhaust valves.

A chain guide 64 for regulating the timing chain 22 is provided. One side of the chain guide 64 is fixed to the cylinder head 6 and the other side is connected to the advancing oil pipe 58 as the pipe member. Provided.

More specifically, as shown in FIGS. 1 and 2, the chain guide 64 is provided at the timing chain 22 between the intake cam sprocket 18 and the exhaust cam sprocket 20.

That is, as shown in FIG. 2, the chain guide 64 is disposed above the free span S of the timing chain 22.

The chain guide 64 is fixed to the cam housing 16 above the cylinder head 6 by fixing bolts 66.
A guide portion 64-2 which is connected to the bracket portion 64-1 and is located on the side of the timing chain 22;
And a reinforcing portion 64-4 communicating with the guide portion 64-3 and communicating with the guide portion 64-2. And an elastic member 64-5 made of rubber, sponge, or the like, which is mounted on the back surface of the regulating portion 64-3.

The distance L between the elastic member 64-5 of the chain guide 64 and the fixing bolt 66 for attaching the chain guide 64 to the cam housing 16 is relatively long. Part 6
4-4 is integrally connected to the advance oil pipe 58, so that both ends are supported.

Next, the operation will be described.

When the engine 2 is driven, the driving force from the crankshaft is transmitted through the crank sprocket and the timing chain 22 to the intake and exhaust cam sprockets 1.
8 and 20, the intake camshaft 12 and the exhaust camshaft 1
Rotate 4.

Then, the intake and exhaust cam sprockets 1
The timing chain 22 wound around 8, 8 is moved outward by the hydraulic actuator 34 between the intake cam sprocket 18 and the exhaust cam sprocket 20 on the advance or retard side and centrifugal force, that is, FIGS. At 2, it is pushed upward.

At this time, the timing chain 22 is mounted on the back surface of the regulating portion 64-3 of the chain guide 64 having the both ends supporting structure provided at the upper portion of the timing chain 22 between the intake cam sprocket 18 and the exhaust cam sprocket 20. The vibration of the timing chain 22 is effectively regulated by contacting the elastic member 64-5.

Thus, the one side is fixed to the cylinder head 6 and the other side is connected to the advancing oil pipe 58 as the pipe member.
4, the chain guide 64 can be in a state of a support structure at both ends, the strength of the chain guide 64 can be improved, the vibration of the timing chain 22 can be effectively controlled, and the timing chain 22 and the intake cam sprocket 18 Also, the meshing state with the exhaust cam sprocket 20 becomes accurate, and noise and wear can be reduced, which is practically advantageous.

Also, since the chain guide 64 is provided at the timing chain 22 between the intake cam sprocket 18 and the exhaust cam sprocket 20, one of the sprockets is rapidly advanced or retarded by the hydraulic actuator 34. When the phase is shifted to the side, it is possible to regulate the timing chain 22 where the slackest occurs.

Further, the chain guide 64 is connected to a guide portion 64-2 located on the side of the timing chain 22.
And a restricting portion 64-3 which communicates with the guide portion 64-2 and is located above the timing chain 22. A reinforcing member which is continuous with the restricting portion 64-3 and faces the guide portion 64-2. With the configuration having the portion 64-4, the chain guide 64 can be formed in a U-shape, and the strength of the chain guide 64 can be improved.

FIG. 5 shows a second embodiment of the present invention.

In the second embodiment, parts that perform the same functions as those in the first embodiment will be described with the same reference numerals.

In the first embodiment described above, the chain guide 64 is formed by the bracket portion 64-1 and the guide portion 6
4-2, a regulating portion 64-3, and a reinforcing portion 64-4 and an elastic member 64-5. The features of the second embodiment are as follows. The reinforcing portion 64-4 in the example is abolished, and the distal end portion of the restricting portion 64-3 is integrally fixed to the upper surface portions of the advance oil pipe 58 and the retard oil pipe 60, which are pipe members, to support both ends. In the structure.

That is, the chain guide 72 is divided into a bracket portion 72-1, a guide portion 72-2, and a regulating portion 72-.
3 and an elastic member 72-4.

At this time, the chain guide 72
And the timing chain 2
2. A tip end portion of a regulating portion 72-3 located above the upper portion 2 is integrally fixed to an upper surface portion of an advancing oil pipe 58 and a retarding oil pipe 60, which are pipe members, respectively, so that both ends are supported. It is.

In this case, the one side is fixed to the cylinder head 6 and the other side is connected to the upper surface of the advancing oil pipe 58 and the retarding oil pipe 60 which are the pipe members. By the guide 72, the chain guide 72 can be in a state of a support structure at both ends, similarly to the above-described first embodiment, the strength of the chain guide 72 can be improved, and the vibration of the timing chain 22 can be effectively restricted. Accordingly, the meshing state of the timing chain 22 with the intake cam sprocket and the exhaust cam sprocket becomes accurate, and noise and wear can be reduced, which is practically advantageous.

If the chain guide 72 is provided at the timing chain 22 between the intake cam sprocket and the exhaust cam sprocket, one of the sprockets is suddenly moved by a hydraulic actuator as in the first embodiment. When the phase is shifted to the advance side or the retard side, the timing chain 22 where the slack occurs most can be regulated.

Further, the chain guide 72 is connected to a guide portion 72-2 located on the side of the timing chain 22.
And a regulating portion 73-3 communicating with the guide portion 72-2 and positioned above the timing chain 22, the chain guide 72 can be formed in an L-shape. As in the first embodiment, the strength of the chain guide 72 can be improved,
The shape of the chain guide 72 can be simplified, which can contribute to cost and weight reduction.

FIG. 6 shows a third embodiment of the present invention.

The feature of the third embodiment is that the position of attachment of the chain guide 82 to the cam housing 16 in the above-described second embodiment is increased.

That is, as shown in FIG. 6, the mounting boss portion 84 of the cam housing 16 is extended so as to be at a height position higher than the timing chain 22, and a chain formed on the mounting boss portion 84 in a flat plate shape. The guide 82 is attached.

In this case, the chain guide 82 can be formed in a flat plate shape, and the shape of the chain guide 82 can be simplified, which can contribute to cost and weight reduction.

Further, the chain guide 82 provided with one side fixed to the cylinder head 6 and the other side connected to the upper surface portions of the advancing oil pipe 58 and the retarding oil pipe 60 as the pipe members. Thus, the chain guide 82 can be in a state of supporting both ends, and the strength of the chain guide 82 can be improved as in the above-described first and second embodiments.
Of the timing chain 22 can be effectively regulated.
The meshing condition between the intake cam sprocket and the exhaust cam sprocket is accurate, and noise and wear can be reduced, which is practically advantageous.

Further, if the chain guide 82 is provided at the timing chain 22 between the intake cam sprocket and the exhaust cam sprocket, one of the sprockets can be hydraulically operated, as in the first and second embodiments. When the phase is suddenly advanced to the advance side or the retard side by the actuator, the timing chain 22 at the portion where the slackening occurs most can be regulated.

FIG. 7 shows a fourth embodiment of the present invention.

The feature of the fourth embodiment is that the chain guide 92 is arranged on the tension side of the timing chain 22.

That is, a portion connecting the crankshaft 94 and the exhaust camshaft 14 of the timing chain 22 and a portion where the guide member 96 is not provided, that is, the right exhaust camshaft 14 and the guide member 96 in FIG. The chain guide 92 is disposed outside the timing chain 22 (hereinafter also referred to as a “free span portion”).

That is, the chain guide 92 is disposed at the M position and outside the timing chain 22, and one side of the chain guide 92 is fixed to the cylinder head 6 with fixing bolts 98.
And the other side is integrally connected to the first pipe 102 forming the advance oil passage and the second pipe 104 forming the retard oil passage.

Then, one side is fixed to the cylinder head 6 and the other side is the first and second pipes 102, 104.
Chain guides 92 integrally connected to the
7, the chain guide 92 can be in a state of supporting both ends, and the exhaust cam shaft 1 on the right side in FIG.
4 and the guide member 96, the vibration of the timing chain 22 can be effectively regulated, and the meshing state of the timing chain 22, the intake cam sprocket 18 and the exhaust cam sprocket 20 becomes accurate, and noise and wear are reduced. This can be reduced, which is practically advantageous, and can improve the strength of the chain guide 92.

The present invention is not limited to the above-described first to fourth embodiments, and various application modifications are possible.

For example, in the first embodiment of the present invention, the chain guide 64 is attached to the cam housing 16 above the cylinder head 6 by a fixing part 66-1 and a bracket part 64-1.
4-1 and a guide portion 64-2 which is located on the side of the timing chain 22, and a regulating portion 6 which is in contact with the guide portion 64-2 and which is located above the timing chain 22.
4-3, and a reinforcing portion 64-4 continuous with the regulating portion 64-3 and facing the guide portion 64-2.
And an elastic member 6 mounted on the back surface of the regulating portion 64-3.
4-5, the chain guide 112 may be provided with a roller member 114 in place of the elastic member 64-5.

That is, as shown in FIG. 8, the chain guide 112 communicates with a bracket (not shown), a guide (not shown) connected to the bracket and located on the side of the timing chain 22, and a guide. And a regulating unit 112 located above the timing chain 22.
And a reinforcing member 112-2 which is continuous with the restricting portion 112-1 and faces the guide portion, and a roller member 114 rotatably provided at both ends of the restricting portion 112-1. Have

At this time, the outer peripheral portion of the roller member 114 is formed by an elastic member.

Then, the sliding noise between the timing chain 22 and the chain guide 112 can be reduced by the roller member 114, which is practically advantageous.

In the first embodiment of the present invention, one side of the chain guide 64 is fixed to the cylinder head, and the other side is connected to a pipe member to form a support structure at both ends. It is also possible to adopt a special configuration in which the chain guide 122 is integrally provided.

That is, a chain guide 122 projecting toward the cylinder head (not shown) is integrally provided on the back surface of the head cover 8.

At this time, the chain guide 122
As shown in FIG. 9, two projecting arms 124, 124 projecting from the back surface of the head cover 8 toward the cylinder head (not shown) and facing each other, and at the lower ends of these projecting arms 124, 124 It has a regulating portion 126 that connects the two projecting arms 124, and an elastic member 128 made of rubber, sponge, or the like attached to the back surface of the regulating portion 126.

Then, it is possible to realize the chain guide 122 in the state of the both ends supporting structure, to improve the strength of the chain guide 122, and to effectively restrict the vibration of the timing chain 22. The meshing condition between the timing chain 22 and the intake cam sprocket and the exhaust cam sprocket becomes accurate, noise and wear can be reduced, which is practically advantageous, and the number of parts can be reduced by integrally forming the head cover 8 and the chain guide 122. Can be reduced.

When the chain guide 122 is formed on the head cover 8, a length parallel to the moving direction of the timing chain 22 is arbitrarily set, and is formed not only at one position but also at two or more positions. Timing chain 22
Can be more effectively regulated.

[0085]

As described above in detail, according to the present invention, the cam sprocket provided on the camshaft supported on the cylinder head of the engine and the crankshaft provided on the crankshaft supported on the cylinder block are provided. In the chain guide that communicates with the crank sprocket via the timing chain and provides an oil passage for supplying oil discharged from the oil pump to the cylinder head in the chain guide that regulates the timing chain, the oil passage is provided in the timing chain chamber in the cylinder head cover. Since the head-side oil passage is provided and the head-side oil passage is formed by a pipe member, the chain guide is provided with one side fixed to the cylinder head and the other side connected to the pipe member.
One side is fixed to the cylinder head, and the other side is connected to the pipe member, and the chain guide is provided with both ends supported by the chain guide. Vibration can be effectively regulated, the timing chain and the cam sprocket mesh accurately, and noise and wear can be reduced, which is practically advantageous.

Further, a cam sprocket provided on a cam shaft supported on a cylinder head of the engine and a crank sprocket provided on a crank shaft supported on a cylinder block are connected via a timing chain.
In a chain guide that regulates the timing chain, a hydraulic actuator that changes the rotation phase of one of an intake cam sprocket and an exhaust cam sprocket around which the timing chain is wound and a cam shaft to which the sprocket is attached is provided. An oil passage for supplying oil discharged from the oil pump to the hydraulic actuator is provided.The oil passage is provided with a head-side oil passage provided in the timing chain chamber in the cylinder head cover, and the head-side oil passage is formed by a pipe member. On the other hand, the chain guide has one side fixed to the cylinder head and the other side connected to the pipe member, so that one side is fixed to the cylinder head and the other side is connected to the pipe member. This by the chain guide Engaido be a state of the both ends support structure, the strength of the chain guide can be improved, and obtained effectively regulate the vibration of the timing chain,
The meshing state between the timing chain and the cam sprocket becomes accurate, and noise and wear can be reduced, which is practically advantageous. Further, even when one of the sprockets is suddenly phase-advanced or retarded by the hydraulic actuator, it is possible to regulate the timing chain where the slackest occurs.

[Brief description of the drawings]

FIG. 1 is a schematic enlarged sectional view of a chain guide portion showing a first embodiment of the present invention.

FIG. 2 is a partially cutaway front view of a chain cover portion of the engine.

FIG. 3 is a sectional view taken along line 3-3 in FIG. 2;

FIG. 4 is an enlarged plan view of a chain cover portion of the engine.

FIG. 5 is a schematic enlarged sectional view of a chain guide portion showing a second embodiment of the present invention.

FIG. 6 is a schematic enlarged sectional view of a chain guide portion showing a third embodiment of the present invention.

FIG. 7 is a schematic enlarged sectional view of a chain guide portion showing a fourth embodiment of the present invention.

FIG. 8 is a schematic enlarged view of a chain guide portion showing another first embodiment of the present invention.

FIG. 9 is a schematic enlarged view of a chain guide portion showing another second embodiment of the present invention.

FIG. 10 is a partially cutaway front view of a chain cover portion of an engine showing the first prior art of the present invention.

FIG. 11 is a sectional view taken along line 11-11 of FIG. 10;

FIG. 12 is a partially cutaway front view of a chain cover portion of an engine showing a second prior art of the present invention.

FIG. 13 is a partially cutaway side view of a chain cover portion of the engine.

[Explanation of symbols]

 2 Engine 4 Cylinder block 6 Cylinder head 8 Head cover 10 Chain cover 12 Intake camshaft 14 Exhaust camshaft 16 Cam housing 18 Intake cam sprocket 20 Exhaust cam sprocket 22 Timing chain 24 Timing chain chamber 32 Variable valve timing (“VVT”) device 34 Hydraulic actuator 36 Oil control valve P Joint surface between cylinder head and cylinder block 54 Advance oil passage 56 Delay oil passage 58 Advance oil pipe 60 Delay oil pipe 62 Housing oil passage 64 Chain guide 64-1 bracket part 64-2 guide part 64-3 regulating part 64-4 reinforcing part 64-5 elastic member

Claims (4)

[Claims] A cam sprocket provided on a camshaft supported on a cylinder head of an engine and a crank sprocket provided on a crankshaft supported on a cylinder block are connected via a timing chain. In the chain guide that regulates the timing chain,
An oil passage for supplying oil discharged from the oil pump to the cylinder head is provided, the oil passage includes a head-side oil passage provided in a timing chain chamber in the cylinder head cover, and the head-side oil passage is formed by a pipe member. A chain guide, wherein one side of the chain guide is fixed to the cylinder head and the other side is connected to the pipe member. 2. A cam sprocket provided on a camshaft supported on a cylinder head of an engine and a crank sprocket provided on a crankshaft supported on a cylinder block via a timing chain. In the chain guide that regulates the timing chain,
A hydraulic actuator that changes the rotational phase of one of the intake cam sprocket and the exhaust cam sprocket around which the timing chain is wound and the cam shaft to which the sprocket is attached is provided, and the oil discharged from the oil pump is provided. Providing an oil passage for supplying to the hydraulic actuator, the oil passage including a head-side oil passage provided in a timing chain chamber in a cylinder head cover, and forming the head-side oil passage with a pipe member; A chain guide having one side fixed to the cylinder head and the other side connected to the pipe member. 3. The chain guide according to claim 2, wherein the chain guide is provided on a timing chain between an intake cam sprocket and an exhaust cam sprocket. 4. The chain guide includes a guide portion located on a side of the timing chain and a regulating portion located above the timing chain, and the regulating portion has a reinforcing portion facing the guide portion. 1 or Claim 2
Chain guide described in.