JPH06193696A - Builtup structure of tensioner - Google Patents

Abstract

PURPOSE:To provide a tensioner's builtup structure which is able to keep off any jumpingness of a plunger in a state of being temporarily clamped. CONSTITUTION:Since a plunger 11 is energized in an X1 direction by a spring 10r, an engaged pin 18 of this plunger 11 is stuck fast to one end 13x of an engaging hole 13a and secured. In this state intact, a tensioner 1 is inserted into a mounting hole 40 from an opening 40a in the arrow X1 direction, and thereby a housing 10 is temporarily clamped to the mounting hole 40. In this state, a regulating projection 13c of a lock hook 13 comes into contact with an inner wall 40e of the mounting hole 40, whereby this lock hook 13 is kept in a lock position intact. Subsequently, if the housing 10 is further inserted into the hole, the regulating projection 13c separates from the inner wall 40e, so that the lock hook 13 is made releasable from the lockedness.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an assembling structure for assembling a tensioner having a lock hook for suppressing excessive protrusion of a plunger.

[0002]

2. Description of the Related Art Tensioners for adjusting tension of chains, belts and the like are used in the industrial world. For example, in a chain device that drives a camshaft of an internal combustion engine of a vehicle, a tensioner is used to adjust the tension of the chain. As this tensioner, there is known a tensioner that holds a plunger in a housing so that the plunger can move forward, pivotally supports a lock hook in the housing, and locks the lock hook with a locked pin of the plunger (actual flat opening). 3-35
355).

In this structure, the tensioner can be fixed to the cylinder head while the plunger is retracted in the housing by the locking action of the lock hook, so that the excessive protrusion of the plunger can be prevented and the tension of the chain can be prevented from being excessive.

[0004]

However, in the tensioner described above, there are cases where the lock action by the lock hook cannot be obtained. For example, as can be understood from FIG. 11, the flange portion 100c of the housing 100 is disposed in the cylinder head 6
When the chain 700 moves in the direction of the arrow X2 and pushes the plunger 200 in the same direction while the housing 100 is not firmly attached to the wall surface 600a of 00, that is, the housing 100 is temporarily fixed to the cylinder head 600. There is. In this case, the locked pin 201 moves in the direction of the arrow X2 together with the plunger 200, and the locked pin 201 abuts the lock hook 300, whereby the lock hook 3 moves.
Since 00 is rotated, as shown in FIG. 12, the lock action of the lock hook 300 is released, and the plunger 200 pops out in the direction of arrow X1.

In this way, the plunger 200 is temporarily fixed.
The flange portion 100c, the wall surface 600a
The housing 100 by contacting it with the cylinder head 600.
When it is fixed to the regular fixed position of No. 3, as can be understood from FIG. 13, the protruding amount of the plunger 200 becomes excessively large corresponding to ΔL, the tension of the chain 700 becomes excessive, and the chain 700 lacks in protection.

The present invention has been made in view of the above situation, and an object of the present invention is to provide a tensioner mounting structure capable of preventing the protruding state of the plunger in the temporarily fixed state.

[0007]

SUMMARY OF THE INVENTION A tensioner assembly structure according to the present invention includes a housing, a plunger held in the housing so as to be capable of advancing toward an endless winding body, and biases the plunger in the advancing direction. A tensioner having a spring and a lock hook that is provided on one of the housing and the plunger and that is detachably locked to a locked pin provided on the other side to suppress the advance of the plunger, and the housing of the tensioner are inserted and fixed. The locker of the tensioner is a structure for assembling the tensioner, and the lock hook of the tensioner locks the locked pin to the locked pin while allowing relative movement of the locked pin as the plunger retracts. The locking attitude of the lock hook is regulated so that the locking pin and the locking portion are locked by contacting the stopper and the inner wall surface of the mounting hole of the fixing member, and In a state where not in contact with the wall surface and is characterized in that it comprises a regulating projecting portion disengaging the locking portion from the engaged pin to unlock position.

[0008]

Operation: The housing of the tensioner is inserted into the mounting hole of the fixing member and fixed in the mounting hole. At the time of insertion, if the restricting protrusion of the lock hook is in contact with the inner wall surface of the mounting hole of the fixing member, the lock hook is maintained in the locked posture,
The lock hook and the locked pin are maintained in a locked state. Therefore, the protrusion of the plunger during the temporary fixing is prevented.

If the amount of insertion of the housing is further increased so that the restricting protrusion of the lock hook does not come into contact with the inner wall surface of the mounting hole, the locked position of the lock hook can be released.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the tensioner of the present invention will be described below with reference to FIGS. FIG. 1 shows a state in which the tensioner 1 is temporarily fixed. FIG. 2 shows a state in which the tensioner 1 is fixed in a regular fixing position. FIG. 3 is a perspective view of a main part of the tensioner 1, and FIGS. 4 and 5 show a lock hook.

(Structure of Embodiment) As shown in FIG. 1, a tensioner 1 includes a housing 10, a plunger 11 fitted in a chamber of the housing 10, and a pin 12 on the housing 10.
And a lock hook 13 held by. Here, a wide mounting flange 15 is provided at the rear end of the housing 10, and a plurality of through holes 16 are formed in the mounting flange 15. A compression spring 1 is provided in the chamber of the housing 10.
0r is built in, and the plunger 11 is biased in the direction of the arrow X1 by the compression spring 10r so that it can move forward. Further, a locked pin 18 is provided on the plunger 11 so as to project therefrom.

As shown in FIGS. 3 to 5, the lock hook 13 is provided.
Is a locking hole 13a as a locking part having a long hole extending in the directions of arrows X1 and X2, a mounting hole 13b provided on the base end side of the lock hook 13, and a tip side of the lock hook 13. It is provided with a semicircular disc-shaped restriction protrusion 13c. As shown in FIG. 5, one end 13 of the mounting hole 13b and the locking hole 13a.
The distance from x is indicated by L5, and the height including the restriction protrusion 13c is indicated by H5, as shown in FIG.

In this example, as can be understood from FIG. 1, since the plunger 11 is biased in the arrow X1 direction by the biasing force of the spring 10r, the locked pin 18 of the plunger 11 locks the lock hook 13. The one end 13x of the hole 13a is strongly pressed, whereby the two are detachably locked and the plunger 11 is prevented from protruding excessively. Further, the tensioner 1 is equipped with a no-back mechanism 2. As is well known, the no-back mechanism 2 allows the plunger 11 to move forward in the arrow X1 direction, but prevents the plunger 11 from moving backward in the arrow X2 direction due to the lock function. The no-back mechanism 2 includes a rack 20 formed on the plunger 11, a ratchet 22 rotatably supported by the housing 10, and a lock spring 24 in a compressed state for urging the ratchet 22. Lock spring 24
As a result, the pawl of the ratchet 22 meshes with the rack 20, and this prevents the plunger 11 from retreating in the direction of arrow X2. When the plunger 11 advances in the arrow X1 direction, the ratchet 22 rotates while elastically contracting the lock spring 24, and the no-back function of the no-back mechanism 2 is released.

As shown in FIG. 1, a mounting hole 40 is formed in a penetrating state in a metal cylinder head 4 as a fixing member. The diameter of the mounting hole 40 is set so as to correspond to the height dimension of the housing 10. The mounting hole 40 has openings 40a and 40b at both ends. A plurality of mounting bolts 42 are mounted on the wall surface 40w of the one opening 40a of the cylinder head 4.

Further, the other opening 40b of the cylinder head 4
In the vicinity of the
A slipper 52 that defines a motion locus of 0 is arranged. (Fixing Method) When the tensioner 1 is fixed to the cylinder head 4, the locking hole 13a of the lock hook 13 is fixed.
Is inserted into the locked pin 18 of the plunger 11. Then, as described above, the plunger 11 is strongly urged in the direction of the arrow X1 by the spring 10r, so that the locked pin 18 of the plunger 11 closely contacts and locks with the one end 13x of the locking hole 13a.

In this state, as shown in FIG. 1, while inserting the through hole 16 of the mounting flange 15 into the mounting bolt 42, the tensioner 1 is inserted from the opening 40a into the mounting hole 40 in the arrow X1 direction to mount the housing 10. Temporarily fix in the hole 40. In this state, as shown in FIG. 1, the mounting flange 15 is separated from the wall surface 40w of the cylinder head 4 by a dimension M.
Further, in this state, as shown in FIG.
Since the regulation protrusion 13c of the above is in contact with the inner wall surface 40e of the mounting hole 40, the lock hook 13 is maintained in the locked posture. Therefore, the locked pin 18 and the lock hook 13
The engagement hole 13a is maintained in the engaged state. That is, the lock function of the lock hook 13 is obtained, and excessive protrusion of the plunger 11 at the time of temporary fixing is prevented.

Thereafter, as shown in FIG. 2, the housing 10
Is further inserted in the direction of the arrow X1, the mounting flange 15 is brought into close contact with the wall surface 40w of the cylinder head 4, and the nut 26 is fully tightened to the mounting bolt 42 to fix the housing 10 to the regular fixing position of the mounting hole 40. In this state, when the plunger 50 is pushed by the chain 50 in the direction of the arrow X2 and moved, the locked pin 18 relatively moves in the same direction in the elongated locking hole 13a. Then, as shown in FIG. 2, the restricting protrusion 13c of the lock hook 13 is locked by the plunger 11
When a pressing force acts on the spring 10 in the direction of arrow X2, the spring 10
The urging force acting in the direction of arrow X1 at r disappears, the gravity causes the swinging retreat downward, that is, in the direction of arrow F1, and the locked posture is released. As a result, the lock hook 13 separates from the locked pin 18, and the plunger 11 pops out in the arrow X1 direction.

In this case, the plunger 11 is stopped at a position where the plunger forward drive force by the spring 10r and the tension of the chain 50 are balanced. In this state where the nut 26 is fully tightened and the housing 10 is fixed at the regular fixing position, the tip 10e of the housing 10 is, as shown in FIG.
The regular tip position P1 in the axial direction of the mounting hole 40 is reached, and the tip 11e of the plunger 11 is the regular tip position P2.
Leading to.

By the way, in a state before the tensioner 1 is inserted into the mounting hole 40, the restriction protrusion 13c of the lock hook 13 retreats in the direction of arrow F1 and the locking hole 13a is released from the locked pin 18 for some reason. There is a risk of coming off. In this case, even if the tensioner 1 is inserted into the mounting hole 40, the lock hook 13 retracted in the direction of arrow F1.
Engages with the wall surface 40w of the cylinder head 4, so that the tensioner 1 cannot be inserted any further.

(Effects of Embodiment) As described above, in this embodiment, when the tensioner 1 is inserted and fixed, the restricting protrusion 13c of the lock hook 13 is in contact with the inner wall surface 40e of the mounting hole 40. Then, the lock hook 13 is maintained in the locked posture, and accordingly, the locked pin 18 and the locking hole 13a are maintained in a locked state. Therefore, the lock function of the lock hook 13 prevents excessive protrusion of the plunger 11 during temporary fixing.

Further, in this embodiment, the restricting protrusion 13c of the lock hook 13 has a semi-disc shape. Therefore, when the housing 10 is inserted into the mounting hole 40 of the cylinder head 4, even if the restricting protrusion 13c comes into contact with the inner wall surface 40e of the mounting hole 40, the contact area becomes small, which is advantageous in reducing the insertion resistance. is there. By the way, when the lock hook 13 is retracted and the locking hole 13a is disengaged from the locked pin 18 before the housing 10 is inserted into the mounting hole 40, as described above, it is dropped and retracted by gravity. Lock hook 1
Since 3 comes into contact with the wall surface 40w of the cylinder head 4, the operator, the robot, or the like recognizes the defective insertion of the tensioner 1. Moreover, the tensioner 1 cannot be inserted any more. Therefore, with the plunger 11 protruding excessively,
The housing 10 of the tensioner 1 is securely prevented from being fixed in the mounting hole 40. Therefore, the tension of the chain 50 can be properly maintained.

(Other Examples) The lock hook 13 is not limited to the above-described embodiment, and the lock hook 13 may be rocked and retracted by a spring force. For example, as in the second embodiment shown in FIGS. 6 and 7, the lock hook 13 is formed of a bent leaf spring. Then, when the plunger 11 is biased in the direction of the arrow X1 by the spring 10r, the locked pin 18 of the plunger 11 strongly presses the one end 13x of the locking hole 13a. On the other hand, when the plunger 11 retracts in the direction of arrow X2,
As shown in FIG. 7, the lock hook 13 may be bent in the direction of arrow S1 by the spring force of the lock hook 13 itself, and the lock hook 13 may be disengaged from the locked pin 18. Also in this example, since the lock hook 13 is provided with the restricting protrusion 13c as in the above-described embodiment,
The lock function of the lock hook 13 at the time of temporary fixing is maintained.

8 to 10 show a third embodiment of the present invention. In this example, the lock hook 13 is attached to the housing 1.
A torsion coil spring 71 is interposed on a pivot shaft 70 pivotally supported on 0, and the torsion coil spring 71 causes the lock hook 13 to rotate.
Is energized. In this example, when the plunger 11 is biased by the spring 10r in the direction of the arrow X1, the locked pin 18 of the plunger 11 has the one end 13x of the locking hole 13a.
Will be strongly pressured. Then, when the plunger 11 retracts in the direction of the arrow X2, the lock hook 13 is moved to the arrow S3 by the spring force of the torsion coil spring 71 as shown in FIG.
The lock hook 13 to the locked pin 1
It is also possible to separate from 8. In this example as well, similarly to the above-described embodiment, since the lock hook 13 is provided with the restriction protrusion 13c, the lock function of the lock hook 13 at the time of temporary fixing is maintained.

Besides, the present invention is not limited to the embodiments described above and shown in the drawings. For example, the present invention can be applied not only to a chain device of an internal combustion engine, but also to a chain device and a belt device of other equipment. Etc. can be appropriately modified and implemented without departing from the scope of the invention.

[0025]

According to the tensioner of the present invention, when the restricting protrusion of the lock hook abuts the inner wall surface of the mounting hole of the fixing member during insertion, the lock hook is maintained in the locked posture, Since the locked pin and the lock hook are maintained in a locked state, excessive protrusion of the plunger during temporary fixing is prevented. Therefore, it is possible to prevent the housing of the tensioner from being fixed to the mounting hole with the plunger protruding excessively. As a result, excessive tension of the winding body such as the chain can be avoided, and the protection of the winding body can be improved.

On the other hand, if the restriction projection of the lock hook does not abut the inner wall surface of the mounting hole, the lock hook can be unlocked and the plunger can be moved forward.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a state in which a tensioner is temporarily fixed in a mounting hole.

FIG. 2 is a cross-sectional view showing a state in which the tensioner is fixed to a regular fixing position of a mounting hole.

FIG. 3 is a perspective view of a main part of the tensioner.

FIG. 4 is an enlarged sectional view of a lock hook.

FIG. 5 is an enlarged front view of a lock hook.

FIG. 6 is a configuration diagram of a state in which a lock hook prevents excessive protrusion of the plunger according to the second embodiment.

FIG. 7 is a configuration diagram of a state in which a lock hook is pivotally retracted according to a second embodiment.

FIG. 8 is a front view of a lock hook according to a third embodiment.

FIG. 9 is a configuration diagram of a state in which an excessive protrusion of the plunger is prevented by a lock hook according to the third embodiment.

FIG. 10 is a configuration diagram of a state in which a lock hook is pivotally retracted according to the third embodiment.

FIG. 11 is a cross-sectional view showing a state in which a housing is temporarily fixed to a cylinder head while preventing excessive protrusion of a plunger by a lock hook according to a conventional example.

FIG. 12 is a cross-sectional view of a conventional example, in which a plunger excessively protrudes during temporary fixing.

FIG. 13 is a cross-sectional view of a conventional example in which a housing is permanently fixed to a cylinder head in a state where a plunger is excessively protruded.

[Explanation of symbols]

In the figure, 1 is a tensioner, 10 is a housing, 11 is a plunger, 13 is a lock hook, 13a is a locking hole, and 13c.
Is a restriction protrusion, 18 is a locked pin, 4 is a cylinder head (fixing member), and 40 is a mounting hole.

Front page continuation (72) Inventor Yoshitaka Matsui 2-chome Toyota-cho, Kariya city, Aichi Prefecture Toyota Industries Corporation

Claims (1)

[Claims] 1. A housing, a plunger held by the housing so as to be capable of advancing toward an endless winding body, a spring for biasing the plunger in the advancing direction, and one of the housing and the plunger. A tensioner having a lock hook that releasably locks to a locked pin provided on the other side to suppress the forward movement of the plunger; and a fixing member having a mounting hole into which the housing of the tensioner is inserted and fixed. The lock hook of the tensioner includes a locking portion that locks the locked pin while allowing relative movement of the locked pin when the plunger retracts. The locking posture of the lock hook is regulated so that the locked pin and the locking portion are brought into contact with the inner wall surface of the mounting hole of the fixing member, and are not in contact with the inner wall surface of the mounting hole. In the state, the tensioner assembling structure is characterized in that the tensioner is provided with a restricting protruding portion that releases the locked position from the locked pin.