JP3006264B2 - Engine tensioner - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tensioner for an engine, and particularly to a V-type engine, in which a V-shaped space is effectively used, the entire engine is made compact, and the rigidity of support of an intermediate shaft is reduced. An engine tensioner that can be improved.

[0002]

2. Description of the Related Art Vehicle engines include an engine having cylinders arranged in series, an engine having cylinders opposed to each other, and a V-type engine having cylinders arranged in a V-shape.

FIG. 3 shows a V-type engine. That is, as shown in FIG. 3, a V-type engine 102 has primary and secondary cylinder heads 110 and 112 mounted on primary and secondary cylinder banks 106 and 108 of a V-shaped cylinder block 104. It is configured. A V-shaped space S is formed between the primary cylinder head 110 and the secondary cylinder head 112. A bearing cap 116 that supports the crankshaft 114 is attached to a lower portion of the cylinder block 104. An oil pan (not shown) is mounted below the bearing cap 116.

A crank sprocket 118 is fixedly attached to the crank shaft 114.

[0005] The primary cylinder head 110 is spaced apart at both upper ends, that is, the primary first and primary secondary camshafts 120 and 122 are provided in parallel to be supported. The primary-side first and primary-side second camshafts 12
The first and second primary cam sprockets 124 and 126 are fixedly attached to 0 and 122, respectively.

[0006] The secondary cylinder head 112 is spaced apart at both upper ends, that is, the secondary first and secondary camshafts 128 and 130 are provided in parallel and supported in parallel. ing. The secondary first camshaft 12 and the secondary second camshaft 12
Secondary side first and secondary side second cam sprockets 132 and 134 are fixedly attached to 8 and 130, respectively.

[0007] The primary side first and the secondary side cam sprockets 124, 126, the primary side cylinder bank 106
The primary side cylinder head 110 is fixedly provided with a stud support bolt 140 which is an intermediate shaft that integrally and rotatably supports the primary side timing sprocket 136 and the primary side cam chain sprocket 138.

A secondary timing sprocket 142 is fixedly attached to the secondary first camshaft 128.

In the cylinder block 104, an idler shaft 144 is fixedly provided between the primary and secondary cylinder banks 106 and 108. An idler sprocket 146 is rotatably attached to the idler shaft 144.

The crank sprocket 118, the primary timing sprocket 136, the idler sprocket 146, and the secondary timing sprocket 142 include:
A timing chain 148 is provided by winding.

The primary cam chain sprocket 13
8, the primary side first and primary side second cam sprockets 124,
The primary side cam chain 150 is wound around 126.

Also, the secondary first cam sprocket 1
A secondary cam chain 152 is wound around the 32 and the secondary second cam sprocket 134.

The primary cylinder block 110 includes:
The primary tensioner 154 is fixedly provided by a plurality of tensioner mounting bolts 156. This primary side tensioner 15
Numeral 4 applies a constant tension to the primary cam chain 150 by coming into contact with the primary cam chain 150 from outside.

When the primary tensioner 154 is mounted, the primary timing sprocket 136, the primary cam chain sprocket 138, and the primary first cam sprocket 124 are close to each other. A mounting extension 158 for mounting the side tensioner 154 extends in the space S, and the primary tensioner 154 is mounted on the mounting extension 158.

A secondary tensioner 160 for applying a constant tension to the secondary cam chain 152 is attached to the secondary cylinder head 112 with a fixture (not shown). The secondary tensioner 160 is attached without protruding outward in the plane of the secondary cylinder head 112.

Further, the cylinder block 104 includes:
A timing tensioner 162 for applying a constant tension to the timing chain 148 is attached with a fixture (not shown). The timing tensioner 162 is attached without protruding outward in the plane of the cylinder block 104.

Further, as such a valve train of a V-type engine, for example, Japanese Patent Application Laid-Open No. 2-169808,
It is disclosed in JP-A-2-169809. Japanese Patent Application Laid-Open No. 2-169808 discloses that the center of a side wall of a cylinder block is effectively disposed for an auxiliary machine or the like by transmitting the rotational force of a crankshaft to an upper portion of each bank of the cylinder block via an idler gear. It is intended to reduce the size of the engine. Also, Japanese Patent Application Laid-Open No. 2-169
No. 809 discloses a structure in which an idler gear and a chain for driving a camshaft are provided in each cylinder head, so that an idler gear, a chain, and the like are provided corresponding to a step of each bank of the cylinder block. The chain arrangement of the banks is made the same so as to shorten the total length of the engine, improve the assembly work, and improve the productivity.

[0018]

However, in a conventional V-type engine, as shown in FIG. 3, a primary tensioner 154 for applying a constant tension to the primary cam chain 150 is projected into the space S. Mounting extension 158 installed
Since the space S for mounting parts such as cooling water pipes and auxiliary equipment is small, the space S cannot be effectively used, and when each part is mounted in the space S, If the parts protrude outward, the engine 102
For example, there is a problem that the size of the engine 102 is increased due to the protrusion of the components in the axial direction.

Further, the stud supporting bolt 14 as an intermediate shaft body
0, the primary timing sprocket 136 and the primary cam chain sprocket 138 are rotatably supported, so that the support rigidity of the stud support bolts 140 is reduced, the life of the timing chain 148 is shortened, and noise is reduced. Had the disadvantage of becoming larger.

[0020]

SUMMARY OF THE INVENTION Accordingly, in order to eliminate the above-mentioned disadvantages, the present invention provides a cylinder block having a cylinder head mounted thereon and a crankshaft having a crank sprocket mounted on the cylinder block. First and second camshafts, on which first and second cam sprockets are mounted on the cylinder head, are provided.
An intermediate shaft that integrally and rotatably supports the timing sprocket and the cam chain sprocket between the first and second cam sprockets and the crank sprocket is fixed to the cylinder head, and the timing sprocket is The cam chain sprocket is disposed so as to be driven by the crankshaft via a timing chain, and the cam chain sprocket is connected to the first and second cam sprockets via the cam chain wound around the cam chain sprocket. An engine tensioner arranged to drive the second camshaft and to provide a constant tension to the cam chain, wherein the tensioner is fixedly provided on one surface of a support member. Attach the member to the cylinder head at least at three points of the first to third parts As described above, the first portion of the support member is held by the intermediate shaft, and the second portion of the support member is fixed to the cylinder head between the first and second cam sprockets and the timing sprocket by mounting bolts. Then, a third portion of the support member is fixed to the cylinder head by a mounting bolt outside the cam chain, and the tensioner is a portion surrounded by the first portion, the second portion, and the third portion. The timing sprocket and the first cam sprocket are arranged between the timing sprocket and the first cam sprocket.

[0021]

According to the structure of the present invention, the tensioner is fixed to one surface of the support member, and the support member is at least
A first portion of the support member is held on the intermediate shaft so that the support member is attached to the cylinder head at three points of the three portions, and a second portion of the support member is attached between the first and second cam sprockets and the timing sprocket. A third portion of the support member is fixed to the cylinder head by a mounting bolt outside the cam chain,
The tensioner is a portion surrounded by the first portion, the second portion, and the third portion, and includes the timing sprocket and the first portion.
Since it is located between the cam sprocket and the tensioner, there is no need to protrude part of the cylinder head to the space side in order to attach the tensioner. Even when components such as cooling water pipes and auxiliary equipment are installed in this space, the components do not protrude outward, and the components are prevented from protruding in the axial direction of the engine. Can be made more compact. In addition, since the intermediate shaft is held by the support member, the life of the timing chain is extended,
Generation of noise can also be reduced.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings. 1 and 2 show an embodiment of the present invention. In FIG. 1, reference numeral 2 denotes a V-type engine. The engine 2 is configured such that primary and secondary cylinder heads 10 and 12 are mounted on primary and secondary cylinder banks 6 and 8 of a V-shaped cylinder block 4. A V-shaped space S is formed between the primary cylinder head 10 and the secondary cylinder head 12.

A bearing cap 14 is attached to a lower portion of the cylinder block 4. An oil pan (not shown) is attached to a lower portion of the bearing cap 14.

A crankshaft 16 is provided on the cylinder block 4 and the bearing cap 14 so as to be pivotally supported. A crank sprocket 18 is fixedly attached to the front end of the crankshaft 16.

The primary cylinder head 10 is spaced apart at both upper ends thereof, that is, the primary first and primary second camshafts 20 and 22 are supported in parallel in parallel. . The primary first and primary camshafts 20 and 22 have primary primary and primary second cam sprockets 24 and 2 respectively.
6 is fixedly mounted.

Further, the secondary cylinder head 12 is located apart from each other at both upper ends, that is, the secondary first and secondary camshafts 28, 30 are supported in parallel. It is provided. Secondary first and secondary second camshafts 2
Secondary side first and secondary side second cam sprockets 32 and 34 are fixedly mounted on 8 and 30, respectively.

A primary timing sprocket 36 and a primary cam, which are integrally formed, are provided on the primary cylinder head 10 on the primary cylinder bank 6 side of the primary first and primary secondary cam sprockets 24 and 26. A stud support bolt 40, which is an intermediate shaft that rotatably supports the chain sprocket 38, is fixedly provided.

A secondary timing sprocket 42 is fixedly attached to the secondary first camshaft 28.

In the cylinder block 4, an idler shaft 44 is located between the primary and secondary cylinder banks 6, 8.
Are fixedly provided. This idler shaft 44 has
An idler sprocket 46 is rotatably mounted.

The crank sprocket 18, the primary timing sprocket 36, and the idler sprocket 46
A timing chain 48 is wound around and the secondary timing sprocket 42.

The primary cam chain sprocket 38
And primary-side first and primary-side second cam sprockets 24, 26
, The primary side cam chain 50 is wound around and provided.

The secondary first cam sprocket 3
A secondary cam chain 52 is wound around the secondary cam sprocket 34 and the secondary cam sprocket 34.

A primary tensioner 54 for applying a constant tension to the primary cam chain 50 is attached to the primary cylinder block 10. This primary tensioner 5
As shown in FIG. 1, a fixing bolt 58 is provided on a back surface which is one surface of a bracket 56 which is a triangular and flat support member, as shown in FIG.
It is fixed by 58.

As shown in FIGS. 1 and 2, the primary tensioner 54 is disposed between the primary timing sprocket 36 and the primary cam sprocket 24, and the pressing portion 54a presses the primary cam chain 50 from inside. Thus, a constant tension is applied to the primary cam chain 50.

The bracket 56 has at least a first
The first corner portion 56a, which is the first portion of the triangle, is held by the stud support bolt 40, which is the intermediate shaft, so that the first corner portion 56a is attached to the primary cylinder head 10 at three points of the three portions. The two second corners 56b are formed between the primary first cam sprocket 24, the secondary second cam sprocket 26, and the primary timing sprocket 36 by a single mounting bolt 60-1 so that the primary cylinder head 1 is formed.
0 and fixed to the third
A third corner portion 56c, which is a portion, is fixedly attached to the primary side cylinder head 10 by another mounting bolt 60-2 outside the primary side cam chain 50. The primary tensioner 54 is a portion surrounded by the first portion 56a, the second portion 56b, and the third portion 56c, and includes the primary timing sprocket 36 and the primary first cam sprocket 2
4 and is fixed to the back surface of the bracket 56.

A secondary tensioner 62 for applying a constant tension to the secondary cam chain 52 is attached to the secondary cylinder head 12 with a fixture (not shown). The secondary tensioner 62 is attached without protruding outward in the plane of the secondary cylinder head 12.

Further, a timing tensioner 64 for applying a constant tension to the timing chain 48 is attached to the cylinder block 4 with an attachment (not shown). The timing tensioner 64 is mounted without protruding outward in the plane of the cylinder block 4.

Parts attached to the front side of the internal combustion engine 2, such as these sprockets and chains, are covered from the front by a timing cover 66 as shown in FIG.

Next, the operation of this embodiment will be described.

When the engine 2 operates, the crankshaft 16
At the same time, the crank sprocket 18 rotates, whereby the timing chain 48 rotates, the primary timing sprocket 36 and the primary cam chain sprocket 38 rotate, and the rotation of the primary cam chain 50 causes the primary first and primary sides to rotate. The second camshafts 20 and 22 are rotated. Further, the rotation of the timing chain 48 rotates the secondary timing sprocket 42, thereby rotating the secondary first camshaft 28 and the secondary second cam via the secondary cam chain 52. The shaft 30 rotates.

In this embodiment, the primary tensioner 54 is fixed to the back of the bracket 56 as a support member, and the primary tensioner 54 is attached to the primary timing sprocket 36 and the primary first cam sprocket 2.
The first portion 56a of the bracket 56 is held by the stud support bolt 40 as an intermediate shaft, and the second and third portions 56b, 56c of the bracket 54 are attached to the mounting bolts 60-1, 60-. Primary cylinder head 1 by 2
0, the primary side cylinder head 1 is mounted in the space S between the primary side cylinder head 10 and the secondary side cylinder head 12 in order to mount the primary side tensioner 54.
Since there is no need to protrude a part of the space S, the space S is expanded, many parts can be installed in the space S, and the space S is effectively used. Even if such components are installed, these components do not protrude greatly outwardly, and also in the axial direction of the engine 2 as shown in FIG.
4 does not protrude in the axial direction, so that the entire engine can be made compact.

The stud support bolt 40 is mounted on the bracket 5
6, the support rigidity of the stud support bolts 40 is improved by the bracket 56, thereby improving the life of the timing chain 48 and reducing the noise generated by the timing chain 48. Can be.

Further, in this embodiment, it is only necessary to add the bracket 56 and the two mounting bolts 60, so that the configuration is simple and the cost can be reduced.

[0044]

As is apparent from the above detailed description, according to the present invention, the tensioner is fixedly provided on one surface of the support member, and this support member is attached to the cylinder head at least at three points of the first to third portions. Thus, the first portion of the support member is held by the intermediate shaft, and the second portion of the support member is
The third portion of the support member is fixed to the cylinder head by a mounting bolt outside the cam chain between the second cam sprocket and the timing sprocket, and the tensioner is fixed to the first portion and the second portion. A part surrounded by the part and the third part and disposed between the timing sprocket and the first cam sprocket, it is necessary to protrude part of the cylinder head to the space side in order to mount the tensioner. Instead, the space can be enlarged and the space can be effectively used.

Further, even when components such as cooling water pipes and accessories are installed in this space, the components do not protrude and are prevented from protruding in the axial direction of the engine. Can be made more compact.

Furthermore, since the intermediate shaft is held by the support member, the rigidity of the support of the intermediate shaft is improved, thereby extending the life of the timing chain and reducing the generation of noise by the timing chain. I can do it.

Further, according to the structure of the present invention, only one support member and mounting bolts for mounting this support member are added, so that the structure is simple and the cost can be reduced.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a V-type engine provided with a tensioner.

FIG. 2 is a partial cross-sectional view of the engine taken along line II-II of FIG.

FIG. 3 is a configuration diagram of a conventional V-type engine provided with a tensioner.

[Explanation of symbols]

 2 Engine 4 Cylinder block 10 Primary cylinder head 12 Secondary cylinder head 16 Crankshaft 18 Crank sprocket 20 Primary first camshaft 22 Primary second camshaft 28 Secondary first camshaft 30 Secondary second Cam shaft 36 Primary timing sprocket 38 Primary cam chain sprocket 40 Implantation support bolt 48 Timing chain 50 Primary cam chain 52 Secondary cam chain 56 Bracket 58 Fixing bolt 60 Mounting bolt

Claims (1)

(57) [Claims] 1. A cylinder head is mounted on a cylinder block.
The crank block sprocket is mounted on the cylinder block.
The crankshaft to which the seat is attached
First and second cam sprockets are attached to the Linda head.
The first and second camshafts are provided so as to be pivotally supported, and the first and second camshafts are provided.
Between the cam sprocket and the crank sprocket
Timing sprocket and cam chain sprocket
An intermediate shaft that integrally and rotatably supports the
The timing sprocket is fixed to the
Is driven by the crankshaft via a timing chain.
The cam chain sprocket is disposed so as to be driven.
The first and second cam sprockets and the cam chain
Via a cam chain wound around the sprocket
The first and second cam shafts are arranged to drive the first and second cam shafts.
Are arranged to apply a certain tension to the cam chain.
In a tensioner for an engine, the tensioner is fixedly provided on one surface of a support member, and the support member is provided at least.
Also attached to the cylinder head at three points of the first to third parts
So that the first portion of the support member is secured to the intermediate shaft.
And the second portion of the support member is brought into contact with the first and second cams.
Between the sprocket and the timing sprocket
Fix to the cylinder head with bolts,
A third part of the holding member is attached to the outside of the cam chain by a mounting bolt.
And fixed to the cylinder head with the tension
The first part, the second part, and the third part surround the corner.
The timing sprocket and the
An engine tensioner disposed between the first cam sprocket and the first cam sprocket .