JPH06174019A - Assembly structure of tensioner - Google Patents

Abstract

PURPOSE:To recognize the removal of the pawl of a rotary hook, that is, an excessive running-out of a plunger, when the housing of a tensioner is inserted and fixed. CONSTITUTION:Even though a pawl 13a is removed from a locked pin 18a for some cause, when a tensioner 1 is inserted to the installing hole 40 of a cylinder head 4, the pawl 13a of a rotary hook 13 rotated downward by the gravity is provided in a groove 46. Since the pawl 13a is hit and engaged to the stopper vertical wall surface 46c of the groove 46, the tensioner 1 cannot be inserted any more, and a housing 10 cannot be fixed to a regular position. As a result, an abnormal insertion is recognized by a worker and the like.

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 swivel hook for preventing excessive protrusion of a plunger, and more particularly to a tensioner assembling structure for avoiding erroneous assembling of the tensioner.

[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, as shown in FIG. 10, a plunger 200 is movably held in a housing 100, and a swivel hook 30 is attached to the housing 100 by a shaft 101.
0 is pivotably supported, and the claw portion 301 of the swivel hook 300 is
There is known a system in which the lock is locked to the locked pin 201 of the plunger 200 (Japanese Utility Model Laid-Open No. 3-35355).
(Kaikai 56-170347).

By the way, the tip 200 of the plunger 200
When a is excessively projected from the regular position P5 in the direction of arrow A1, the tensioner is fixed to the internal combustion engine.
Not preferable. The main reason for this is that excessive protrusion of the plunger 200 induces excessive tension in the chain, causing problems such as damage or breakage of the chain, and lacking in chain protection.

Therefore, in the tensioner described above, FIG.
As shown in FIG. 5, the claw portion 301 of the swivel hook 300 is locked to the locked pin 201 of the plunger 200, so that the housing 100 is retracted in the retracted state.
Is fixed to the internal combustion engine, the excessive protrusion of the plunger 200 is prevented. After the assembly, the plunger 200 pushed by the swing of the chain is attached to the locked pin 2
01, the locked pin 201 is disengaged from the claw portion 301, so that the plunger 200 moves forward in the direction of arrow A1 to a position balanced with the tension of the chain.
While maintaining the proper tension of the churn, the swing hook 3
00 revolves downward due to gravity, that is, in the direction of arrow B1 and retreats.

[0005]

In the above tensioner, as described above, when the housing 100 is fixed to the internal combustion engine, the swing hook 300 and the locked pin 201 are engaged by the excessive action of the plunger 200. Has the advantage of being blocked. However, in some cases, the locking action of the swivel hook 300 and the locked pin 201 cannot be obtained. For example, during assembly work, the camshaft or crankshaft may be rotated to assemble the pulley, sprocket, etc. while the tensioner is temporarily fixed to the internal combustion engine. Tension is applied, and at this time, the locked pin 201 may separate from the claw portion 301, and the plunger 200 may pop out excessively.

When the housing 100 is fixed to the internal combustion engine without detecting the disengagement of the turning hook 300, that is, the excessive protrusion of the plunger 200, excessive tension of the chain is induced as described above, and the chain is not protected. .
The present invention has been made in view of the above circumstances, and an object of the present invention is to prevent an excessive amount of a plunger by restricting insertion into a mounting hole of a housing when a turning hook is detached when the housing is inserted and fixed. (EN) A tensioner assembling structure capable of preventing a protruding 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 a pivotally pivotally supported member in the housing. A tensioner having a swivel hook having a claw for releasably locking the locked portion of the plunger to prevent the plunger from advancing, and a fixing member having a mounting hole into which the housing of the tensioner is inserted and fixed. This is a tensioner assembly structure.When inserting the housing of the tensioner into the mounting hole, and when the swivel hook is not locked to the locked part of the plunger, it is engaged with the swivel hook and regulates the insertion of the housing. The part is provided in a mounting hole of the fixed part. In general, the insertion restricting portion can be formed in the shape of an upright wall which is provided upright in a direction substantially perpendicular to the axis of the mounting hole.

[0008]

Operation: The housing of the tensioner is inserted into the mounting hole of the fixing member and fixed in the mounting hole. During insertion, when the swivel hook is not locked to the locked part of the plunger,
Since the insertion restricting portion of the mounting hole and the turning hook engage with each other, the insertion of the housing is restricted.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the tensioner of the present invention will be described below with reference to FIGS. (Structure of Embodiment) FIG. 1 shows a state before the tensioner 1 is fixed. As shown in FIG. 1, a tensioner 1 includes a housing 10, a plunger 11 fitted in a chamber of the housing 10 to which engine oil pressure is supplied, and a swing hook pivotally supported by a shaft 12 on the housing 10. 13 and 13. 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 10r is built in the chamber of the housing 10, and the plunger 11 is biased in the direction of the arrow X1 by the compression spring 10r.
Further, the plunger 11 is provided with a locked pin 18 as a locked portion. The claw portion 13a at the tip of the turning hook 13 is detachably locked to the locked pin 18 of the plunger 11 to prevent the plunger 11 from excessively protruding.

Further, the tensioner 1 is equipped with a no-back mechanism 2 having a lock function. 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 on the housing 10 by a shaft 22a, and a lock spring 24 in a compressed state for urging the ratchet 22. The ratchet 22 is urged by the lock spring 24, and the pawl 22i of the ratchet 22 meshes with the rack 20, whereby the locking function of the no-back mechanism 2 is obtained, and the plunger 1
The backward movement of 1 in the arrow X2 direction is prevented. When the plunger 11 moves forward in the direction of arrow X1, the ratchet 22 moves in the direction of arrow C1 while elastically contracting the lock spring 24.
The pawl 22i is disengaged from the rack 20 and the lock 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 D1 of the mounting hole 40 is the housing 10
The height dimension H1 is set to correspond to the height dimension H1. The mounting hole 40 has openings 40a and 40b at both ends. A plurality of mounting bolts 42 and gaskets 44 are provided on the wall surface side of the one opening 40a of the cylinder head 4.

Further, a groove 46 is formed in the lower inner wall surface 40n of the mounting hole 40 of the cylinder head 4. The groove 46 is formed by a bottom wall surface 46a, an upright wall surface 46b in an upright state with respect to the bottom wall surface 46a, and a stopper upright wall surface 46c as an insertion restricting portion facing the upright wall surface 46b.
The stopper standing wall surface 46c is formed in an upright state. As shown in FIG. 2, in the vicinity of the other opening 40b of the cylinder head 4, a chain 50 and a slipper 52 that defines a movement trajectory of the chain 50 are arranged.

When the tensioner 1 is fixed, as shown in FIG. 1, the tensioner 1 is attached to the mounting hole 40 in a state where the claw portion 13a of the turning hook 13 is locked to the locked pin 18 of the plunger 11. Face to face. Then, while fitting 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. Then, with the turning hook 13 still locked to the locked pin 18, as shown in FIG.
Is fully tightened to each mounting bolt 42, and the housing 10 is fixed to the regular fixing position of the mounting hole 40.

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 a regular tip in the axial direction of the mounting hole 40 as shown in FIG. The position P1 is reached, and the tip 11e of the plunger 11 reaches the regular tip position P2. After that, when the chain 50 swings as the internal combustion engine is driven,
Since the plunger 11 is pushed in by the abutting portion 52k of the slipper 52 and the plunger 11 retracts together with the locked pin 18 in the direction of the arrow X2, the locked pin 18 is moved to the claw portion of the swivel hook 13 as shown in FIG. 13a of the turning hook 13 is automatically detached from the shaft 13a, and the claw portion 13a of the swivel hook 13 falls downward, that is, in the direction of the arrow Y1 around the shaft 12 due to gravity, and is retracted to the claw portion retracted position F1. As shown in FIG. 3, the claw portion retracted position F1 is located closer to the opening 40b than the stopper standing wall surface 46c.

When the claw portion 13a is detached in this way, the tip 11e of the plunger 11 moves from the normal tip position P2 to the arrow X.
The plunger 11 stops further at a position where the plunger forward drive force of the housing 10 and the tension of the chain 50 are balanced by further advancing in one direction. As described above, in the state where the housing 10 is fixed at the regular fixing position, as can be understood from FIG. 5, the groove 46 and the stopper standing wall surface 46c are positioned within the turning trajectory β of the claw portion 13a of the turning hook 13. In addition, it is located closer to the opening 40a than the turning locus β in the axial direction of the mounting hole 40.

By the way, in a state where the tensioner 1 is inserted into the mounting hole 40, the claw portion 1 is for some reason caused.
3a may come off from the locked pin 18. For example, in the state before the nut 26 is fully tightened to the mounting bolt 42, when the camshaft or the crankshaft is rotated and tension is applied to the chain due to work circumstances, the claw portion 13a is locked. The plunger 11 may come off from the pin 18 and jump out excessively. in this case,
As shown in FIG. 4, due to gravity, the claw portion 13 of the turning hook 13 is
a falls into the groove 46 and is placed in the groove 46. Alternatively, even when the claw portion 13a does not immediately drop into the groove 46, the claw portion 13a drops into the groove 46 as the housing 10 is further inserted.

As a result, the tensioner 1 is moved to the arrow X further.
Even if an attempt is made to insert the tensioner 1 in one direction, the claw portion 13a collides with and engages with the stopper standing wall surface 46c of the groove 46, so that the tensioner 1 cannot be inserted any further. Therefore,
The defective insertion of the tensioner 1 is recognized by an operator, a robot or the like. Specifically, as can be understood from FIG. 4, the screw exposure amount Δ of the mounting bolt 42 with respect to the mounting flange 15 is Δ.
If L is insufficient and the nut 26 is to be fully tightened on the male screw portion 42a of the mounting bolt 42, the final tightening cannot be performed, and the imperfect insertion of the tensioner 1 is surely recognized.

In this case, the through hole 1 of the mounting flange 15
6 is removed from the mounting bolt 42, and the tensioner 1 is taken out from the opening 40a of the mounting hole 40. Then, the pawl portion 22i of the ratchet 22 of the no-back mechanism 2 is manually operated.
When the plunger 11 is pushed in the direction of the arrow X2 while the no-back mechanism 2 is unlocked by detaching from the rack 20, if the claw portion 13a and the locked pin 18 are locked,
Again, the tip 11e of the plunger 11 is maintained in the retracted state. After that, the tensioner 1 is inserted into the mounting hole 40 through the opening 40a and fixed in the same manner as described above.

(Effects of the Embodiment) As described above, in this embodiment, when the pawl portion 13a of the turning hook 13 is detached when the tensioner 1 is inserted and fixed, the pawl portion 13a which has fallen due to gravity falls within the groove 46. Is located in. Therefore, if you try to insert the tensioner 1 further in the direction of arrow X1,
Since the claw portion 13a collides with the stopper standing wall surface 46c, the defective insertion of the tensioner 1 is recognized by an operator, a robot, or the like. Moreover, the tensioner 1 cannot be inserted any more. Therefore, the housing 10 of the tensioner 1 is prevented from being fixed to the mounting hole 40 when the plunger 11 is still protruding excessively. Therefore, the tension of the chain 50 can be properly maintained.

(Other Example) FIGS. 6A to 6D show a configuration according to another example. FIG. 6A shows a state in which the groove 46 and the stopper standing wall surface 46c are located on the side of the opening 40a, and the swivel hook 13 is standing upright and is in collision and engagement with the stopper standing wall surface 46c. Show. FIG. 6 (B) shows
With the swivel hook 13 lying considerably, the stopper standing wall surface 4
6c shows a state of collision engagement with 6c. In FIG. 6C, a step portion 48 is formed in the mounting hole 40, and the turning hook 13 collides and engages with the stopper standing wall surface 46 c forming the step portion 48. In FIG. 6D, the swivel hook 13 collides with and engages with the stopper standing wall surface 46c forming the slot 49 provided in the cylinder block 4.

By the way, when the claw portion 13a of the swivel hook 13 is disengaged from the locked pin 18 while the housing 10 is being inserted, as shown in FIG.
When the cylinder head 4 is turned so that 6c is located above, the swing hook 13 swings downward due to gravity,
The claw portion 13a of the turning hook 13 is not arranged in the groove 46. In this regard, in the second embodiment shown in FIG. 7, the tension spring 10
One end of h is locked to the swivel hook 13, and the tension spring 10h
The other end of the spring is locked to the housing 10, and the tension spring 1
The turning hook 13 is biased by the spring force of 0 h. Therefore, once the claw portion 13a is detached from the locked pin 18,
The turning hook 13 is turned in the direction of the arrow E2 by the spring force of the tension spring 10h, and the claw portion 13a is reliably arranged in the groove 46. Therefore, regardless of the height position of the groove 46, the claw portion 13
It becomes possible for a to collide and engage with the stopper standing wall surface 46c.

A third embodiment of the present invention is shown in FIG. In this example, the taper standing wall surface 46e as the insertion restricting portion has an angle θ.
It has a tapered shape. Therefore, tensioner 1
If the claw portion 13a is to be further inserted, the claw portion 13a climbs along the tapered wall surface 46e, so that the claw portion 13a can be inserted. However, since the claw portion 13a climbs along the tapered standing wall surface 46e, the insertion resistance when the tensioner 1 is further inserted increases, and due to the increase in the insertion resistance, an "insertion abnormality", i.e., the claw portion, is given to the operator. It is possible to recognize the excessive protrusion of the plunger 11 due to the separation of 13a.

In this case, the tensioner 1 is attached to the mounting hole 40.
You don't have to remove it completely. That is, the no-back mechanism 2 is unlocked by the operator's fingertip or the like thrown into the opening 40b side, and in that state, the plunger 11 is pushed in the direction of the arrow X2 to engage the claw portion 13a and the locked pin 18. When stopped, the tip 11e of the plunger 11 is retracted again, and the plunger 11 is prevented from protruding excessively.

(Example of Application) FIG. 9 shows an example of application to an internal combustion engine equipped with a chain device. The internal combustion engine is equipped with a camshaft timing gear 90, a crankshaft timing gear 91, and a chain damper 92.
An endless timing chain 50 is installed on 91. Mounting hole 40 for cylinder head 4 of internal combustion engine
The tensioner 1 is inserted and fixed in the. Tensioner 1
The tension on the slack side of the timing chain 50 is adjusted by the slipper 52 biased by.

In addition, the present invention is not limited to the embodiments and application examples described above and shown in the drawings. For example, the swivel hook may be formed by bending a wire to reduce the weight, or The present invention can be applied to not only the chain device of an internal combustion engine, but also the chain device and belt device of other equipment, etc., and can be appropriately modified and implemented without departing from the scope of the invention.

[0026]

According to the tensioner of the present invention, when the pawl portion of the turning hook is disengaged when the tensioner is inserted and fixed in the mounting hole, the pawl portion engages with the insertion restricting portion, so that the tensioner is further inserted. If you try, the insertion is restricted. Therefore, the defective insertion of the tensioner is recognized by the worker, the robot or the like. Therefore, it is possible to prevent the tensioner housing from being fixed in the mounting hole when the plunger is protruding excessively, and it is possible to avoid excessive tension of the winding body such as the chain, thereby protecting the winding body. Can increase.

[Brief description of drawings]

FIG. 1 is a sectional view of a state before a tensioner is inserted into 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 cross-sectional view showing a state where a turning hook of a tensioner fixed at a regular fixing position of a mounting hole is detached.

FIG. 4 is a cross-sectional view showing a state in which a swiveling hook that has been detached is engaged with a stopper standing wall surface during insertion.

FIG. 5 is a configuration diagram showing a positional relationship between a turning locus of a claw portion of a turning hook and a stopper standing wall surface in a state where a housing is fixed at a regular fixing position.

6A to 6D are configuration diagrams showing respective forms of a claw portion of a turning hook and a stopper standing wall surface.

FIG. 7 is a cross-sectional view showing a state in which a turning hook that has been disengaged is engaged with the stopper vertical wall surface during insertion according to the second embodiment.

FIG. 8 is a cross-sectional view according to the third embodiment, showing a state in which a swiveling hook that has been disengaged is engaged with a tapered wall surface during insertion.

FIG. 9 is a front view showing an application example of an internal combustion engine including a tensioner and a chain.

FIG. 10 is a front view of a tensioner according to a conventional example.

[Explanation of symbols]

In the figure, 1 is a tensioner, 10 is a housing, 11 is a plunger, 13 is a swivel hook, 13a is a claw part, 18 is a locked pin (locked part), 2 is a no-back mechanism, 4 is a cylinder head (fixed). Member), 40 is a mounting hole, 46 is a groove, 46
Reference numeral c indicates a stopper vertical wall surface (insertion restricting portion), and 50 indicates a chain.

Claims (1)

[Claims] 1. A housing, a plunger held by the housing so as to be capable of advancing toward an endless winding body, and pivotably supported by the housing so as to be detachable from a locked portion of the plunger. A tensioner assembling structure comprising a tensioner having a turning hook having a claw portion for stopping the plunger to prevent the plunger from moving forward, and a fixing member having a mounting hole into which the housing of the tensioner is inserted and fixed, When inserting the housing of the tensioner into the mounting hole,
An insertion restriction portion that engages with the rotation hook and restricts insertion of the housing when the turning hook is not locked to the locked portion of the plunger is provided in the mounting hole of the fixing portion. Tensioner assembly structure characterized by