JPH084848A - Tensioner arm and chain guide - Google Patents

Abstract

PURPOSE:To provide a tensioner arm and a chain guide by which deterioration of properties of engine oil can be prevented. CONSTITUTION:In a tensioner arm 20 for adding tensile force to the timing chain 9 of an engine, through holes 28, 29 are formed on the tension arm, as an oil releasing part for releasing oil to be accumulated in recessed parts 21 on the back surface side of the tensioner arm 20. Thereby oil can be prevented from being accumulated on the back surface of the tensioner arm for a long period of time.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tensioner arm which gives a proper tension to a chain inside an engine, and a chain guide which regulates a traveling position of the chain.
More specifically, it relates to improvements in the structures of these tensioner arms and chain guides.

[0002]

2. Description of the Related Art Generally, in a timing system used for driving a valve operating system of an internal combustion engine, a tensioner arm is provided with a tensioner on the loose side of a timing chain, and a chain guide is provided on the tension side.

The body of each of the tensioner arm and the chain guide is generally made of a metal member such as aluminum, and a recess is formed on the back surface side (the side opposite to the chain contacting side) for weight reduction and material reduction. It is often done.

[0004]

On the other hand, in a timing system for a V-type engine or the like, the tensioner arm and the chain guide are arranged in an oblique direction, so that the engine oil scattered during operation is stored in the recess on the rear side. Easy to accumulate.

Since the oil accumulated in the recess does not circulate in the engine, the properties of the oil may deteriorate especially when the engine is stopped for a long time.

The present invention has been made in view of the above-mentioned conventional circumstances, and an object of the present invention is to provide a tensioner arm and a chain guide capable of preventing deterioration of properties of engine oil.

[0007]

A tensioner arm according to the present invention is a tensioner arm for applying tension to a chain provided inside an engine, wherein an oil escape portion is provided on the back side of the tensioner arm. It has a feature.

It is preferable that the oil escape portion is formed of a through hole that penetrates from the back side of the tensioner arm to the chain contact side.

It is preferable that the oil escape portion is formed of a through hole penetrating from the back side of the tensioner arm to the side wall side.

It is preferable that the oil escape portion is composed of a bottom wall portion that extends in a substantially horizontal direction on the back side of the tensioner arm at the attachment position of the tensioner arm.

The chain guide according to the present invention is characterized in that, in the chain guide for restricting the traveling position of the chain provided inside the engine, an oil escape portion is provided on the back side of the chain guide.

It is preferable that the oil escape portion is formed of a through hole that penetrates from the back side of the chain guide to the chain contact side.

It is preferable that the oil escape portion is formed of a through hole penetrating from the back side of the chain guide to the side wall side.

It is preferable that the oil escape portion is composed of a bottom wall portion extending in a substantially horizontal direction on the back side of the chain guide at the mounting position of the chain guide.

[0015]

According to the tensioner arm of the present invention, since the oil escape portion for releasing the oil is provided on the rear side of the tensioner arm, it is possible to prevent the oil from accumulating on the rear side of the tensioner arm for a long time. As a result, the deterioration of the properties of the engine oil can be prevented.

According to the chain guide of the present invention, since the oil escape portion for releasing the oil is provided on the back side of the chain guide, it is possible to prevent the oil from accumulating on the back side of the chain guide for a long time. As a result, the deterioration of the properties of the engine oil can be prevented.

[0017]

Embodiments of the present invention will be described below with reference to the accompanying drawings. 1 to 8 are views for explaining a tensioner arm and a chain guide according to an embodiment of the present invention, FIG. 1 is a view showing a timing system of a V-type engine to which the present embodiment is applied, and FIG. FIG. 3 is a plan view of the present tensioner arm, FIG. 3 is a front view thereof, FIG. 4 is a plan view of the chain guide, FIG. 5 is a front view thereof, and FIG. 6 is a diagram for explaining the operation and effect of the present embodiment (tensioner arm). 7 is a sectional view taken along line VII-VII in FIG. 3, and FIG. 8 is a sectional view taken along line VIII-VIII in FIG.

As shown in FIG. 1, the timing system 1 includes two drive sprockets 3 and 3 fixed to a crankshaft 2 and driven sprockets 6 and 7 fixed to camshafts 4 and 5, respectively. A timing chain 8 wound between the sprockets 3 and 6 and a timing chain 9 wound between the sprockets 3 and 7 are provided. The arrow in FIG. 1 indicates the rotation direction of the crankshaft 2.

Tensioner arms 10 and 20 for applying tension to the timing chains 8 and 9 are provided on the loose sides of the timing chains 8 and 9, and the running positions of the timing chains are restricted on the tension sides, that is, the timing chains are guided. Chain guides 30 and 40 are provided for each of them.

The tensioner arms 10 and 20 include an arm body (main body) 11 made of, for example, an aluminum die cast, and a shoe (sliding member) 12 made of rubber or resin such as nylon attached to the chain contact side. It has each. A bolt 13 that rotatably supports the arm body 11 is inserted into a hole formed at one end of the arm body 11. The bolt 13 is screwed and fixed to the side wall of the engine. A hydraulic tensioner 15 is disposed on the side of the other end of the arm body 11, and the pressing shaft 15
a presses the arm body 11 toward the chain contact side.

Like the tensioner arms 10 and 20, the chain guides 30 and 40 include a guide body (main body) 31 made of, for example, an aluminum die cast, and a rubber or resin such as nylon mounted on the chain contact side. And a shoe 32 of each. The guide body 31 is fixed to the side wall of the engine by bolts 33 inserted into the holes at both ends of the guide body 31.

Arm body 11 of tensioner arm 20
2, FIG. 3, FIG. 7 and FIG. 8, a recess 21 extending in the longitudinal direction is formed on the back surface side (the side opposite to the chain contact side). That is, the arm body 11 is
It is composed of a bottom wall portion 22 on which the shoe 12 is mounted and side wall portions 23, 23 rising from both ends in the width direction. Also, the bottom wall 2 is provided near one end of the arm body 11.
2 is continuously formed with a thick wall portion 24, and the thick wall portion 24 and the side wall portions 23, 23 are penetrated to form the bolt 13
(FIG. 1) An insertion hole 25 is formed. Further, a reinforcing rib 26 is provided at a substantially central portion of the arm body 11 in the longitudinal direction.
Is provided.

On the shoe 12 of the tensioner arm 20,
The protrusions 27 protruding toward the arm body 11 are formed at three locations, and the bottom wall portion 22 of the arm body 11 is formed with locking holes 22a at which the protrusions 27 can be retained at three locations. There is. When the shoe 12 is attached to the arm body 11, one end 12b of the shoe 12 is locked to the end of the arm body 11, and the entire shoe is attached to the curved surface 22b of the arm body bottom wall portion 22. At this time, the projections 27 of the shoe 12 are locked in the corresponding locking holes 22a on the arm body 11 side, and the tips of the projections 27 are welded (see FIG. 8). As a result, the shoe 12 is fixed to the arm body 11. Also shoe 12
An engaging recess 12a with which the timing chain 9 can travel is engaged.

Arm body 11 of tensioner arm 20
Through holes 28 and 29 are formed in the shoe 12.

The through hole 28 collects engine oil accumulated in a concave portion (a concave portion on the left side of FIG. 3 with the rib 26 sandwiched) 21 surrounded by the thick portion 24, the rib 26, the side wall portions 23, 23 and the bottom wall portion 22. It is to be released to the timing chain 9 side, and is formed on the bottom wall portion 22 of the rising start portion of the thick portion 24. Further, the position where the through hole 28 is formed is located at the position where the timing chain 9 enters the tensioner arm 20 at the mounting position (see FIGS. 1 and 6).

The through hole 29 includes the rib 26, the side wall portions 23,
The rib 2 is provided for releasing the engine oil accumulated in the recess 21 (the recess on the right side of FIG. 3 with the rib 26 in between) 23 and the bottom wall 22 to the timing chain 9 side.
6 is formed on the bottom wall 22 at the bottom.

As described above, the through holes 28 and 29 are formed at the lowest position in each recess 21 at the mounting position of the tensioner arm 20.

Regarding the tensioner arm 10,
Except that the through holes 28 and 29 are not formed,
The structure is similar to that of the tensioner arm 20 and will not be described here.

The guide body 31 of the chain guide 30 includes the arm body 1 of the tensioner arms 10 and 20.
As in the case of No. 1, a recess 41 extending in the longitudinal direction is formed on the back side thereof (see FIGS. 4 and 5), whereby the guide body 31 has a bottom wall portion 42 on which the shoe 32 is mounted,
It is composed of side walls 43, 43 rising from both ends in the width direction. Thick-walled portions 44a and 44b are formed continuously with the bottom wall portion 42 near the respective end portions of the guide body 41, and the thick-walled portions 44a and 44b and both side wall portions 43 and 43 are A hole 45 for inserting the bolt 33 (FIG. 1) is formed.

Although not shown in FIGS. 4 and 5,
The shoe 32 is formed with a locking projection, and the guide body 31 is formed with a locking hole into which the projection can be locked. As in the case of the tensioner arms 10 and 20, each projection is locked in each corresponding locking hole on the guide body side, and the tip of each projection is welded, so that the shoe 32 is attached to the guide body 31. Fixed.

Further, the guide body 3 of the chain guide 30
1 and the shoe 32, like the tensioner arm 20, through holes 48, 49 which are escape holes for engine oil.
Are formed.

The through hole 48 is provided to allow the engine oil collected in the recess 41 surrounded by the thick wall portion 44a, the side wall portions 43, 43 and the bottom wall portion 42 to escape to the timing chain 8 side. It is formed near the rising portion of the portion 44a. The through hole 49 is formed in the thick portions 44a, 44.
b, the engine oil collected in the recess 41 surrounded by the side wall portions 43, 43 and the bottom wall portion 42 is supplied to the timing chain 8
It is to be released to the side, and is formed on the bottom wall portion 42 at the rising start portion of the thick portion 44b. That is,
Each through hole 48, 49 is formed at the lowest position in each recess 41 at the mounting position of the chain guide 30 (see FIG. 1).

The chain guide 40 has the same structure as the chain guide 30 except that the through holes 48 and 49 are not formed, and a description thereof will be omitted.

Next, the function and effect of this embodiment will be described. The engine oil splashed during the operation of the timing system 1 is the tensioner arm 20 and the chain guide 30.
Into the concave portions 21 and 41 on the rear surface side of the. This state will be described with reference to FIG. 6 illustrates the tensioner arm 20 as an example, the same applies to the chain guide 30, and only the tensioner arm 20 will be described here. Further, in the figure, 9a indicates a link plate which constitutes the timing chain 9.

The oil L accumulated in the recesses 21 on the lower side and the upper side of the ribs 26 is dropped on the timing chain 9 side through the through holes 28, 29 formed at the lowest positions in the recesses 21. . This prevents oil from accumulating in the recess 21 on the back side of the tensioner arm 20 for a long time,
The oil can be circulated in the engine, and as a result, the deterioration of the properties of the oil can be prevented.

On the other hand, in general, in the case of a V-type engine, since it is difficult to supply oil between the sliding portion of the tensioner arm and the timing chain, in the conventional case, the shoe is significantly worn or the space between the shoe and the timing chain is increased. However, in the present embodiment, since oil is supplied from the through holes 28 and 29 between the shoe 12 and the timing chain 9, the conventional problem is solved. it can.

In general, the shoe 12 is likely to be worn at the entry point of the timing chain 9, but as described above, the opening of the through hole 28 on the shoe 12 side is located at the entry point of the timing chain 9. Therefore, it is possible to suppress the progress of wear of the shoe 12.

[ First Modification ] In the above embodiment, the recesses 21 and 41 formed on the back side of the tensioner arm 20 and the chain guide 30 have a rectangular cross section (FIGS. 7 and 8). However, the application of the present invention is not limited to this, and may be a wedge-shaped recess 51 as shown in FIG.

FIG. 9 is a view corresponding to FIG. 7 of the above-mentioned embodiment, that is, the tensioner arm 20 of this first modified example.
The same reference numerals as those in FIG. 7 indicate the same or corresponding portions. Since the chain guide 30 can be applied in the same manner, only the tensioner arm 20 side will be described here.

In FIG. 9, the wedge-shaped recess 51 has a width dimension w which becomes smaller as it goes downward, and the oil that has entered the recess 51 is likely to collect downward. As a result, the oil in the recess 51 can be easily guided to the through holes 28, 29, and the oil can be smoothly discharged from the through holes 28, 29.

[ Second Modification ] In the above-described embodiment and the first modification, the tensioner arm 20 and the chain guide 30 are provided.
Although an example in which the respective oil escape through holes are formed in the bottom wall portions 22 and 42 of the arm body 11 and the guide body 31 has been shown, the application of the present invention is not limited to this, and FIGS. As shown in FIG.
You may make it form 8,59.

FIGS. 10, 11 and 12 respectively correspond to FIGS. 2, 3 and 7 of the above embodiment, that is, this second modification is applied to the tensioner arm 20. , The same reference numerals in the corresponding drawings indicate the same or corresponding portions. Since the chain guide 30 can be applied in the same manner, only the tensioner arm 20 side will be described here.

In each drawing, the through hole 58 is formed in both side wall portions 23, 23 of the rising start portion of the thick portion 24, and the through hole 59 is formed in the both side wall portions 23, 23 below the rib 26.
Is formed. Also, the bottom wall portion 52 of the arm body 11
Has a raised central portion in the width direction (see FIG. 12), which allows the oil that has entered the recess 21 to be easily guided to the through holes 58 and 59.
The oil can be smoothly discharged from 8, 59.

[ Third Modification ] In the above-described embodiment and the first and second modifications, the oil escape portion for escaping the oil accumulated on the back side of the tensioner arm 20 and the chain guide 30 is formed by the through hole. I showed an example of the configuration,
The application of the present invention is not limited to this.

For example, as shown in FIG. 13, the arm body 11 may be formed of a member having an inverted T-shaped cross section, which is composed of a bottom wall portion 60 and a standing wall portion 61 rising from the central portion thereof. In this case, since no recess for accumulating oil is formed on the back side of the tensioner arm 20,
The shape of the tensioner arm 20 itself constitutes the oil escape portion.

Further, the sectional shape of the arm body 11 is not limited to this inverted T type, but may be I type. In any case, the weight of the entire arm body 11 can be reduced. Here, FIG. 13 is a view corresponding to FIG. 7 of the above-described embodiment, that is, showing a case where this third modification is applied to the tensioner arm 20, and the same reference numerals as those in FIG. The same or corresponding parts are shown. In addition, the same applies to the chain guide 30, so
The description is omitted here.

Further, as shown in FIG. 14, the arm body 11 is made up of a bottom wall portion 62 and side wall portions 63, 63 projecting downward from both widthwise end portions of the chain contacting side. Good. In this case, the recess 64 of the arm body 11 is formed on the chain contact side, and the chain 9 is housed in the recess 64. Although FIG. 14 illustrates the tensioner arm 20 as an example, such a cross-sectional shape can be similarly applied to the guide body 31 of the chain guide 30.

FIG. 15 shows an example in which the tensioner arm 20 and the chain guide 30 having such a sectional shape are applied to the timing system of FIG. In this case, since the flat surfaces of the bottom wall portion 62 are arranged on the respective back sides of the tensioner arm 20 and the chain guide 30 and no recess for accumulating oil is formed, as in the case of FIG. The shape of the tensioner arm 20 itself constitutes the oil escape portion.

Further, in this case, as shown in FIG. 15, most of the side wall portions 63 are disposed in the winding inner space of the chains 8 and 9, so that the tensioner arm 20 in the winding outer space. And chain guide 30
The occupancy amount can be reduced, and the degree of freedom in layout design of other components can be increased. In particular, when the tensioner arm 20 and the chain guide 30 are made of aluminum die-cast, which is generally highly rigid, the cross-sectional area can be made smaller than when made of resin, so that the overall size can be reduced and the winding The occupancy in the outer space can be further reduced.

When the tensioner arm 10 and the chain guide 40 shown in FIG. 15 have the same cross-sectional shape, the amount of the tensioner arm and the chain guide in the chain winding outer space is further reduced in the entire timing system. it can. At this time, the tensioner arm 10 and the chain guide 40
By arranging the concave portion on the chain contacting side, the oil scattered in the engine is easily collected in the concave portion, whereby the lubricity of the shoe 12 can be improved and wear of the chain can be suppressed. In this case, the shoe 12
If a notch or the like is formed in the side wall portion of oil, it becomes easier to introduce oil into the chain running portion or the engagement recess 12a.

[ Fourth Modification ] The oil escape portions on the back side of the tensioner arm 20 and the chain guide 30 are
The present invention is not limited to those shown in the above embodiment and the first to third modifications. For example, as shown in FIGS. 16 and 17, the thick portion 70 near the center of the arm body 11 is a flat and gently inclined surface, and the rear surface (right side surface in FIG. 14) 71 of the rib 26 is thick portion 70. The oil escape portion may be configured by forming an inclined surface that is inclined in substantially the same direction as.

16 and 17 are views corresponding to FIGS. 3 and 6 of the above embodiment, respectively, and the same reference numerals in the corresponding drawings indicate the same or corresponding portions. Since it can be applied to the chain guide 30 in exactly the same way,
Here, only the tensioner arm 20 side will be described.

When the tensioner arm 20 is placed at the mounting position (see FIG. 1), as shown in FIG.
Are arranged at a horizontal position or a position slightly inclined downward (the same applies to the rear surface 71 of the rib 26). For this reason, the oil that has entered the recess on the back side of the tensioner arm 20 has a thick portion 70 as shown by the arrow in FIG.
It will move downwards through the inclined surface of, and will be discharged to the outside through the thick portion 24. In this way, it is possible to prevent oil from accumulating in the recess on the back side.

[ Other Application Examples ] In the above-mentioned embodiment and the first to fourth modified examples, the present invention is applied to the timing system of the V-type engine, but the application of the present invention is V.
Not limited to type engines.

FIG. 18 shows an example in which the present invention is applied to a timing system of an in-line DOHC engine. In FIG. 18, reference numeral 80 is a crankshaft, 81, 82
Is a cam shaft, and a timing chain 86 is wound around the drive sprocket 83 and the driven sprockets 84 and 85. A tensioner arm 87 and a tensioner 88 are arranged on the loose side of the timing chain 86, and a chain guide 89 is arranged on the tight side. These tensioner arms 87,
The tensioner 88 and the chain guide 89 have the same configurations as the tensioner arm 10, the tensioner 15, and the chain guide 40 of FIG. 1, respectively.

A chain guide 90 for guiding the timing chain 86 is arranged between the driven shafts 84 and 85. A through hole 91 is formed in the center of the chain guide 90 in the longitudinal direction to allow oil to enter into the recess on the back side. Since the chain guide 90 is arranged in the horizontal direction, oil is likely to collect in the rear recess, but the through hole 91 allows the oil in the recess to be easily discharged.

FIG. 19 shows an example in which the present invention is applied not only to the timing system (FIG. 18) but also to the balancer drive. Note that in FIG.
The same reference numerals as those in 8 indicate the same or corresponding portions.

In the figure, the balancer shafts 95, 96
A balancer chain 100 is wound between each driven sprocket 97, 98 and the drive sprocket 99 of FIG. Has been done. A chain guide 104 for guiding the balancer chain 100 is arranged between the driven sprockets 95 and 96.

The chain guide 104 has a through hole 10 for letting out oil entering the recess on the back side.
5, 106 are formed. Since the chain guide 104 is arranged in the horizontal direction, oil is likely to collect in the recess on the rear surface side like the chain guide 90, but oil can be easily discharged from the recess by the through holes 105 and 106.

Further, as another application example, the present invention is applied to a timing system when an inclining engine is mounted on a vehicle in a series engine, or to a drive chain for auxiliary machines such as an oil pump and a generator. There are cases where it will be done. In any of these cases,
The present invention effectively works when the tensioner arm and the chain guide are arranged in an inclined state or in a horizontal state.

[0061]

As described above, according to the tensioner arm and the chain guide of the present invention, since the oil escape portion is provided on the back side, it is possible to prevent the oil from being accumulated on the back side for a long time. It is effective in preventing deterioration of properties.

[Brief description of drawings]

FIG. 1 is a diagram showing a timing system of a V-type engine to which a tensioner arm and a chain guide according to an embodiment of the present invention are applied.

FIG. 2 is a plan view of the tensioner arm.

FIG. 3 is a front view of the tensioner arm.

FIG. 4 is a plan view of the chain guide.

FIG. 5 is a front view of the chain guide.

FIG. 6 is a view for explaining the action and effect of the embodiment (tensioner arm).

7 is a sectional view taken along line VII-VII of FIG.

8 is a sectional view taken along line VIII-VIII of FIG.

FIG. 9 is a diagram corresponding to FIG. 7 showing a first modification of the present invention.

FIG. 10 is a diagram corresponding to FIG. 2 showing a second modification of the present invention.

FIG. 11 is a diagram corresponding to FIG. 3 showing a second modification of the present invention.

FIG. 12 is a diagram corresponding to FIG. 7 showing a second modification of the present invention.

FIG. 13 is a diagram corresponding to FIG. 7 showing a third modification of the present invention.

FIG. 14 is a diagram corresponding to FIG. 7 showing a third modification of the present invention.

FIG. 15 is a diagram corresponding to FIG. 1 showing a timing system of a V-type engine to which a tensioner arm and a chain guide according to the third modified example (FIG. 14) are applied.

FIG. 16 is a diagram corresponding to FIG. 3 showing a fourth modification of the present invention.

FIG. 17 is a diagram corresponding to FIG. 6 showing a fourth modification of the present invention.

FIG. 18 is a diagram showing an example in which the present invention is applied to a timing system of an in-line DOHC engine.

FIG. 19 is a diagram showing an example in which the present invention is applied to a timing system of an in-line DOHC engine and a drive system of auxiliaries.

[Explanation of symbols]

 1 Timing system 8,9 Timing chain 10,20 Tensioner arm 30,40 Chain guide 12,32 Shoe 15 Tensioner 21,41 Recessed portion 22,42 Bottom wall portion 23,43 Side wall portion 28,29,48,49 Through hole (oil (Escape hole)

Claims (8)

[Claims] 1. A tensioner arm for applying tension to a chain provided inside an engine, wherein a tensioner arm is provided with an oil relief portion on the back side of the tensioner arm. 2. A chain guide for restricting a traveling position of a chain provided inside an engine, characterized in that an oil escape portion is provided on a rear side of the chain guide. 3. The tensioner arm according to claim 1, wherein the oil relief portion is formed of a through hole penetrating from the back side of the tensioner arm to the chain contact side. 4. The tensioner arm according to claim 1, wherein the oil relief portion is formed of a through hole that penetrates from the back side of the tensioner arm to the side wall side. 5. The oil escape portion according to claim 1, wherein the oil relief portion is composed of a bottom wall portion that extends in a substantially horizontal direction on the back side of the tensioner arm at the attachment position of the tensioner arm. Tensioner arm to do. 6. The chain guide according to claim 2, wherein the oil escape portion is formed of a through hole that penetrates from the back side of the chain guide to the chain contact side. 7. The chain guide according to claim 2, wherein the oil escape portion is formed of a through hole that penetrates from the back side of the chain guide to the side wall side. 8. The oil escape portion according to claim 2, wherein the oil escape portion is composed of a bottom wall portion extending substantially horizontally on the back side of the chain guide at the mounting position of the chain guide. Chain guide to do.