JP5004928B2 - Synthetic shoe shoe integrated tensioner - Google Patents

Description

  The present invention relates to a synthetic resin shoe-integrated tensioner that applies an appropriate tension to a chain of a chain transmission mechanism that is suspended between a drive-side sprocket and a driven-side sprocket and transmits power. The present invention relates to a synthetic resin shoe integrated tensioner suitable for applying an appropriate tension to a chain of a chain transmission mechanism.

In general, an engine timing drive system includes a chain that circulates around a sprocket provided on each of a crankshaft and a camshaft in an engine room.
In addition to this, the timing drive system is provided with an auxiliary drive mechanism comprising a chain suspended between sprockets provided on each of the crankshaft and an auxiliary drive shaft such as an oil pump. The drive shaft has a short inter-axis distance, and the accessory drive mechanism is provided with a synthetic resin shoe-integrated tensioner that applies appropriate tension to the chain (see Patent Documents 1 and 2).

An example of a conventional synthetic resin shoe integrated tensioner is shown in FIGS.
A conventional synthetic resin shoe-integrated tensioner 1 has a tensioner body 2 pivotally supported by a lever type synthetic resin shoe 5.
The tensioner body 2 includes an integrally formed arm 3, and a pin press-fitting hole 4 is formed in the arm 3.
Also, a frame body 6 having a U-shaped cross section is formed on the mounting base end side of the synthetic resin shoe 5, and through holes 8 are formed in both side walls 7 of the frame body 6.

When the synthetic resin shoe integrated tensioner 1 is assembled, the synthetic resin shoe 5 is attached to the arm 3 of the tensioner body 2 via the frame 6, and the through hole formed in the frame 6 of the synthetic resin shoe 5 is penetrated. The pins 9 are inserted into the holes 8 and 8 and the pin press-fitting hole 4 of the arm 3.
In this case, the pin 9 is press-fitted and fixed in the pin press-fitting hole 4 of the arm 3 and is loosely fitted into the through holes 8 and 8 of the synthetic resin shoe 5 so that the synthetic resin shoe 5 is attached to the tensioner. It is pivotally supported by the body 2.
JP 2000-65145 A (paragraph number 0017, FIGS. 1 and 2) Japanese Utility Model Publication No. 62-114251

The conventional synthetic resin shoe-integrated tensioner 1 has a problem that the synthetic resin shoe 5 cannot be easily attached and detached because the pin 9 is press-fitted and fixed to the pin press-fitting hole 4 of the arm 3.
Moreover, the accuracy of the pin press-fitting hole 4 and the pin 9 of the tensioner body 2 is required in order to prevent cracks around the pin press-fitting hole 4 and damage to the pin 9 when the pin 9 is press-fitted. However, there is a problem that it is difficult to improve accuracy with a high yield, and there is actually a problem that defective products are generated in the manufacturing process and the assembling process.
Further, since the pin 9 is used for the pivotal support means, there is a problem that an extra number of parts is required and the weight is increased and the number of assembling steps is increased.

  Therefore, the present invention solves the problems of the prior art as described above, that is, the object of the present invention is to eliminate the press-fitting and fixing of the pins and to easily attach and remove the synthetic resin shoe. In addition to reducing the occurrence of defective products as much as possible, the wear of the pair of spherical locking projections formed on the pivot hole provided in the arm of the tensioner body and the frame of the synthetic resin shoe is reduced, thereby improving the assemblability. It is an object of the present invention to provide a synthetic resin shoe-integrated tensioner that improves and applies appropriate tension to a chain.

  According to the first aspect of the present invention, a synthetic resin shoe of a lever type is pivotally supported with respect to a single pivot hole drilled in an arm of a tensioner body to give an appropriate tension to the chain. In the resin shoe-integrated tensioner, a pair of spherical locking projections formed on each inner wall surface of the frame body inside a U-shaped frame body formed on the mounting base end side of the synthetic resin shoe The spherically engaging projections of the frame body mounted on the arm are fitted into the pivotal support holes of the arm from both sides so that the synthetic resin shoe can be attached to and removed from the tensioner body. The arm of the tensioner body includes a curved portion concentric with the pivot hole, and a curved surface that is in concentric contact with the curved portion of the arm and is in sliding contact is provided with the synthetic resin shoe. Formed into By being formed in the interior of the shaped frame of the cross-section U is obtained by solving the problems described above.

  According to a second aspect of the present invention, in the synthetic resin shoe-integrated tensioner according to the first aspect of the present invention, a spherical locking projection portion fitted into a pivotal support hole of the arm from both sides and the tensioner body are provided. The above-described problem is further solved by receiving the force applied from the chain by the plunger and the entire area of the curved portion provided on the arm.

According to the first aspect of the present invention, the lever type synthetic resin shoe is pivotally supported with respect to one pivotal support hole formed in the arm of the tensioner body so as to give an appropriate tension to the chain. In the synthetic resin shoe-integrated tensioner, a pair of spherical locks formed on each inner wall surface of the frame body on the inner side of the U-shaped frame body formed on the mounting base end side of the synthetic resin shoe Protrusions are provided opposite to each other, and each spherical locking projection on the frame mounted on the arm is fitted into the pivot support hole of the arm from both sides, and a synthetic resin shoe is attached to the tensioner body and is pivotably supported. In addition, the tensioner body arm has a pivot portion and a concentric curved portion, and the curved surface formed in the synthetic resin shoe has a curved surface that is in concentric contact with the curved portion of the arm. Character frame Since it is formed inside, the pins used for the pivoting means of the conventional synthetic resin shoe-integrated tensioner and the press-fitting of these pins become unnecessary, so the number of parts can be reduced and the weight can be reduced. The generation of defective products can be reduced as much as possible.
In addition, a pair of spherical locking projections formed on the frame of a synthetic resin shoe is fitted into one pivotal support hole drilled in the arm from both sides of the pivotal support hole, and the synthetic resin is attached to the tensioner body arm. The shoe made can be pivotally supported so as to be freely attached and detached. As a result, the shoe made of synthetic resin can be easily attached and detached, and the assemblability can be improved.
The arm of the tensioner body has a curved portion concentric with the pivot hole, and a curved surface formed in the synthetic resin shoe has a curved surface that is in concentric contact with the curved portion and is in sliding contact. By being formed inside the body, the synthetic resin shoe can be supported concentrically so as to be swingable by the curved portion, the curved surface, and a pair of spherical locking projections fitted in the pivotal support holes. Therefore, it is possible to reduce wear on one pivotal support hole provided on the arm of the tensioner body or a pair of spherical locking projections formed on the frame of the synthetic resin shoe.

  According to the second aspect of the present invention, in addition to the effect produced by the synthetic resin shoe-integrated tensioner according to the first aspect of the present invention, a spherical locking projection portion fitted into the pivotal support hole of the arm from both sides. Since the force applied from the chain is received by the plunger provided on the tensioner body and the entire area of the curved portion provided on the arm, it is possible to reduce the wear of the pivot hole of the arm and the pair of spherical locking projections. it can.

The synthetic resin shoe-integrated tensioner of the present invention is used as, for example, a synthetic resin shoe-integrated tensioner that applies appropriate tension to a chain of an accessory drive mechanism provided in an engine timing drive system.
This auxiliary machine drive mechanism is composed of a chain suspended between sprockets provided on each of the crankshaft and the auxiliary machine drive shaft, and a synthetic resin shoe integrated tensioner is provided on the loose side of the chain.

FIG. 1 shows an engine timing drive system provided with a synthetic resin shoe integrated tensioner 11 of the present invention.
The timing drive system includes a drive sprocket S1 attached to a crankshaft in an engine room and a chain C1 suspended between a pair of driven sprockets S2 and S3 attached to a camshaft.
The accessory drive mechanism HD comprises a chain C2 suspended between sprockets S4 and S5 provided on each of the crankshaft and the accessory drive shaft such as an oil pump. The accessory drive mechanism is on the loose side of the chain C2. A synthetic resin shoe integrated tensioner 11 is provided.
In FIG. 1, reference numeral TL is a tensioner lever that applies tension to the chain C1, reference numeral GL is a guide lever that guides the chain C1, reference numeral T is a tensioner, and reference numeral B is a tensioner lever. It is the pivot axis of TL.

Reference example

First, a synthetic resin shoe integrated tensioner 11 which is a reference example for better understanding the synthetic resin shoe integrated tensioner of the present invention will be described with reference to FIGS.
A synthetic resin shoe-integrated tensioner 11, which is a reference example for better understanding the synthetic resin shoe-integrated tensioner of the present invention, is a pivot hole 14 formed in an arm 13 provided in the tensioner body 12. A lever-type synthetic resin shoe 15 is pivotally supported via the.
The tensioner body 12 is provided with a plunger 12a urged so as to protrude by a spring or hydraulic pressure, and the chain is tensioned by a synthetic resin shoe 15 pressed by the plunger 12a.

The tensioner body 12 is provided with an arm 13, and a pivotal support hole 14 is formed in the arm 13.
The tensioner body 12 and the arm 13 are integrally formed of a metal such as iron or aluminum alloy.
The tensioner body 12 and the arm 13 may be integrally formed of plastic.

The synthetic resin shoe 15 pivotally supported by the arm 13 of the tensioner body 12 is of a lever type, and a frame body 16 having a U-shaped cross section is provided on the mounting base end side of the synthetic resin shoe 15. ing.
Spherical locking projections 18 are formed on the inner wall surfaces 17, 17 of the frame 16, respectively, and the spherical locking projections 18 are opposed to each other inside the frame 16.
The lever type synthetic resin shoe 15 is made of plastic integrally molded with synthetic resin together with the frame 16.
As the synthetic resin, a material that exhibits durability under a high temperature environment and can achieve smooth sliding contact of the chain is suitable. For example, polyamide 6, polyamide 46, polyamide 66, polyacetal, etc. It is preferable to use it.

When assembling the synthetic resin shoe-integrated tensioner 11 as a reference example of the present invention, when the frame body 16 of the synthetic resin shoe 15 is pushed in so as to sandwich the arm 13 of the tensioner body 12, the inner side of the frame body 16 is inserted. A pair of spherical locking projections 18, 18 formed on the wall surfaces 17, 17 are fitted into the pivotal support holes 14 of the arm 13 from both sides, and a synthetic resin shoe 15 is pivotally supported on the tensioner body 12.
For maintenance, the frame 16 may be extracted from the arm 13 using a jig, a tool, or the like, and the synthetic resin shoe 15 may be removed.

  A synthetic resin shoe-integrated tensioner 11 which is a reference example of the present invention is provided on a tensioner body 12 and a pair of spherical locking projections 18 and 18 which are fitted into a pivotal support hole 14 of an arm 13 from both sides. Since the force applied from the chain is received by the plunger 12a, it is functionally inferior to the synthetic resin shoe integrated tensioner 1 using the pin 9 as a conventional pivot means.

A synthetic resin shoe integrated tensioner 21 according to an embodiment of the present invention will be described with reference to FIGS.
The synthetic resin shoe-integrated tensioner 21 according to the embodiment of the present invention has a lever-type synthetic resin shoe 25 pivotally supported on a tensioner body 22, similar to the above-described reference example. The plunger 22a urged by a spring or hydraulic pressure is provided, and the chain is tensioned by being pressed by the synthetic resin shoe 25 via the plunger 22a.
6 and 7, reference numeral 22 b is a mounting hole for the tensioner body 22.

The tensioner body 22 is provided with an arm 23, and one pivotal support hole 24 is formed in the arm 23, and a curved part 23 a concentric with the pivotal support hole 24 is formed at the end of the arm 23. Has been.
The tensioner body 22 and the arm 23 are integrally formed of a metal such as iron or an aluminum alloy.
The tensioner body 22 and the arm 23 may be integrally formed of plastic.

The synthetic resin shoe 25 pivotally supported by the arm 13 of the tensioner body 22 is a lever type, and a frame body 26 having a U-shaped cross section is provided on the mounting base end side of the synthetic resin shoe 25. Yes.
As shown in FIGS. 6 to 7, a curved surface 26 a is formed in the frame body 26 so as to be in concentric contact with the curved portion 23 a of the arm 23 and to be in sliding contact therewith.
In addition, spherical locking projections 28 are formed on the inner wall surfaces 27 and 27 of the frame body 26, respectively, and the pair of spherical locking projections 28 and 28 are opposed to each other inside the frame body 26. Yes.
The synthetic resin shoe 25 and the frame body 26 are made of plastic integrally molded with synthetic resin.
As the synthetic resin, a material that exhibits durability under a high temperature environment and can achieve smooth sliding contact of the chain is suitable. For example, polyamide 6, polyamide 46, polyamide 66, polyacetal, etc. It is preferable to use it.

When assembling the synthetic resin shoe-integrated tensioner 21 according to the embodiment of the present invention, when the frame body 26 of the synthetic resin shoe 25 is pushed in so as to sandwich the arm 23 of the tensioner body 22, the inner side of the frame body 26 is installed. A pair of spherical locking projections 28, 28 formed on the wall surfaces 27, 27 fit into the pivot hole 24 of the arm 23 from both sides, and as shown in FIGS. 6 to 7, The curved surface 26 a of the frame body 26 is brought into close contact with the concentric circle so that the synthetic resin shoe 25 is pivotally supported on the tensioner body 22.
For maintenance, the frame 26 may be extracted from the arm 23 using a jig, a tool, etc., and the synthetic resin shoe 25 may be removed.

  The synthetic resin shoe-integrated tensioner 21 according to the embodiment of the present invention is provided on the tensioner body 22 and a pair of spherical locking projections 28 fitted into the pivotal support hole 24 of the arm 23 from both sides. A force applied from the chain is received by the plunger 22 a and the curved portion 23 a of the arm 23 provided on the tensioner body 22.

The configuration of the synthetic resin shoe integrated tensioner 11 as a reference example of the present invention and the synthetic resin shoe integrated tensioner 21 as an embodiment of the present invention have been described above.
The synthetic resin shoe integrated tensioner 11 which is a reference example of the present invention and the synthetic resin shoe integrated tensioner 21 which is an embodiment of the present invention both have a spherical shape as pivoting means for the synthetic resin shoes 15 and 25. Since the locking projections 18 and 28 are used, the conventional pin 9 is not necessary, and the number of parts can be reduced and the weight can be reduced.
Further, since the conventional press-in of the pin 9 is not required, the accuracy of the pivot holes 14 and 24 of the arms 13 and 23 is eased, and the generation of defective products can be reduced as much as possible.

When the synthetic resin shoes 15, 25 are attached to the arms 13, 23, the frame bodies 16, 26 of the synthetic resin shoes 15, 25 are pushed into the arms 13, 23, and the spherical locking protrusions of the frame bodies 16, 26 are pressed. By simply fitting the portions 18 and 28 into the pivot holes 14 and 24 from both sides, the synthetic resin shoes 15 and 25 can be attached to and detached from the tensioner bodies 12 and 22, respectively.
As a result, the synthetic resin shoes 15 and 25 can be easily attached and detached, and the assemblability can be improved.

Further, like the synthetic resin shoe-integrated tensioner 21 according to the embodiment of the present invention, a bent portion 23a concentric with the pivot hole 24 is formed at the end of the arm 23 of the tensioner body 22, and the synthetic resin shoe. A curved surface 26a is formed in the frame 26 of the arm 23 so as to be in concentric contact with the curved portion 23a of the arm 23 and in sliding contact therewith, so that the synthetic resin shoe 25 is in sliding contact with the curved surface 26a. Can be supported concentrically so as to be swingable by a curved portion 23a and a pair of spherical engaging projections 28, 28 fitted into one pivotal support hole 24 from both sides. As a result, the tensioner body 22 is supported. It is possible to reduce the wear of the pair of spherical locking projections 28, 28 provided in the pivot support hole 24 provided in the shoe or the synthetic resin shoe 25.
Further, a pair of spherical locking projections 28 and 28 fitted into the pivot hole 24 of the arm 23 from both sides, a plunger 22a provided on the tensioner body 12, and a curved portion 23a of the arm 23 provided on the tensioner body 22, Since the force applied from the chain is received, the effect of the wear of the pivotal support hole 24 of the arm 23 and the pair of spherical locking projections 28 and 28 can be reduced.

Explanatory drawing of a timing drive system. The front view of the synthetic resin shoe integrated tensioner which is a reference example for an understanding of the present invention. X3-X3 sectional view taken on the line in FIG. (A) is a front view of a synthetic resin shoe, (B) is a side view of the synthetic resin shoe. The front view of the tensioner body used by the reference example of this invention. The front view of the synthetic resin shoe integrated tensioner which is an Example of this invention. The side view of the synthetic resin shoe integrated tensioner shown in FIG. (A) is a front view of a synthetic resin shoe, (B) is a side view of the synthetic resin shoe. The front view of the tensioner body used by this invention. The front view of the conventional synthetic resin shoe integrated tensioner. X11-X11 sectional view taken on the line in FIG. The side view of a synthetic resin shoe. Side view of the pin.

11, 21 ・ ・ ・ Synthetic resin shoe integrated tensioners 12, 22 ・ ・ ・ Tensioner bodies 12 a, 22 a ・ ・ ・ Plungers 13, 23 ・ ・ ・ Arms 14, 24 ・ ・ ・ Pivot holes 15, 25 ・ ・ ・Synthetic resin shoes 16, 26 ... frame bodies 17 and 27 ... inner wall surfaces 18 and 28 ... spherical locking projection 23a ... curved portion 26a ... curved surface

Claims (2)

In the synthetic resin shoe integrated tensioner, the lever type synthetic resin shoe is pivotally supported with respect to one pivotal support hole drilled in the arm of the tensioner body to give an appropriate tension to the chain.
A pair of spherical locking projections formed on each inner wall surface of the frame body are provided facing each other on the inner side of a U-shaped frame body formed on the mounting base end side of the synthetic resin shoe. In addition, each spherical locking projection of the frame body mounted on the arm is fitted into the pivot support hole of the arm from both sides, and the synthetic resin shoe is pivotally attached to the tensioner body and detachably supported.
The arm of the tensioner body is provided with a curved portion concentric with the pivot hole, and a curved surface formed in the synthetic resin shoe has a curved surface that is in concentric contact with the curved portion of the arm. A synthetic resin shoe-integrated tensioner, characterized in that it is formed inside a frame-shaped frame.   It is characterized in that the force applied from the chain is received by the spherical locking projections fitted into the pivot hole of the arm from both sides, the plunger provided on the tensioner body, and the entire curved part provided on the arm. The synthetic resin shoe integrated tensioner according to claim 1.

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