JP2864401B2 - Tensioner pulley structure of internal combustion engine - Google Patents

Description

The present invention relates to a tensioner pulley structure for an internal combustion engine,
In particular, the number of parts can be reduced, the cost can be reduced, and at the same time, compactness can be achieved and the mounting space can be reduced,
The present invention relates to a tensioner pulley structure of an internal combustion engine capable of applying an initial tension to a predetermined amount and appropriately applying an initial tension.

[Conventional technology]

In an internal combustion engine, in order to drive a valve mechanism and accessories, a belt is wound around each shaft pulley to transmit a driving force. In particular, the timing belt, which is a toothed belt that is wound around the camshaft pulley of the valve mechanism so as to rotate synchronously with the crankshaft pulley of the internal combustion engine, is given an appropriate tension to prevent tooth skipping. , A tensioner is provided.

As the tensioner pulley structure, for example,
There is one shown in FIG. In the drawing, 102 is a tensioner, 104 is a shaft as a fixed member, and 106 is a pulley as a rotating member. The tensioner 102 is provided with a pulley 106 rotatably mounted on the outer periphery of a shaft 104 by a bearing member 108, and a rotation center of the pulley 106 of the shaft 104.
An eccentric hole 112 through which a support bolt 110 serving as a swing shaft is inserted is provided at a position eccentric from C1 through each of the side surfaces 114 and 116 in the axial direction, and a tensioner plate 118 serving as a locking plate fixed to the shaft 104 is provided. An arc-shaped fixing hole 120 having the center C2 of the eccentric hole 112 as the center of rotation is provided on the eccentric hole 112, and a locking portion 122 is provided. A fixing bolt 124 is inserted through the fixing hole 120, and the locking hole of the locking portion 122 is formed. The tensioner plate 118 is fixed to the internal combustion engine (not shown) by the fixing bolt 124 while applying an initial tension by locking one end of a tensioner spring 128 as a tension urging tool to the 126.

Further, as the tensioner pulley structure, for example,
・ There is one shown in Fig. 11. In the figure, 202 is a tensioner, 204 is a shaft as a fixed member, and 206 is a pulley as a rotating member. The tensioner 202 is provided with a pulley 206 rotatably mounted on the outer periphery of a shaft 204 by a bearing member 208, and a pivot shaft 212 at a position eccentric from the rotation center C1 of the pulley 206 on one axial side surface 210 of the shaft 204. The eccentric hole 214 to be fixed is provided, and an arc-shaped fixing hole 216 having the center C2 of the eccentric hole 214 as a center of rotation is provided through each of the axial side surfaces 210 and 218 of the shaft 204. A locking portion 222 is provided on a tensioner plate 220 which is a fixed locking plate, and a fixing bolt (not shown) is inserted into the fixing hole 216 and the locking hole 2 of the locking portion 222 is formed.
The shaft 204 is fixed to an internal combustion engine (not shown) by a fixing bolt while applying an initial tension by locking one end of a tensioner spring 226 which is a tension urging tool to the 24.

Further, as the tensioner pulley structure, for example,
Some are shown in Figures 12 and 13. In the figure, 302 is a tensioner, 304 is a shaft as a fixed member, and 306 is a pulley as a rotating member. This tensioner 302 has a shaft 304
A pulley 306 is rotatably provided on the outer periphery of the shaft 304 by a bearing member 308, and a fixing bolt 310, which is a swing shaft and is a fixing tool, is inserted into a position of the shaft 304 eccentric from the rotation center C1 of the pulley 306. The eccentric hole 312 is inserted into each side 31 in the axial direction.
4 and 316, and an engaging hole 318 for engaging a tension applying jig (not shown) is provided on the other axial side surface 316 of the shaft 304 at a position away from the center C2 of the eccentric hole 312. The shaft 304 is moved toward the internal combustion engine (not shown) by the fixing bolt 310 while inserting a fixing bolt 310 into the eccentric hole 312 and applying an initial tension by engaging a tension applying jig (not shown) in the engaging hole 318. It is fixed.

A tensioner pulley structure as shown in FIGS. 12 and 13 is disclosed in Japanese Patent Application Laid-Open No. 57-120755. The publication discloses a structure in which one side in the axial direction is opened and the other side in the axial direction is closed so that the fixing member can be pressed.

[Problems to be solved by the invention]

However, in the conventional tensioner pulley structure, the tensioner pulley structure shown in FIGS. 8 and 9 and FIGS. 10 and 11 is provided with a locking plate as a tension plate and a tension urging tool as a tension spring. There is a disadvantage that the number of parts increases and the cost increases, and there is a disadvantage that the external shape becomes large and a large mounting space is required. Further, the tension urging tool is an unnecessary part after the fixing member is fixed, and the tension urging tool or the like is damaged or dropped by the vibration of the internal combustion engine and is caught between the driving parts, for example, between the belt and the pulley. This may damage the internal combustion engine. Furthermore, there is a disadvantage that the initial tension fluctuates due to the variation of the tension urging tool, and the predetermined initial tension cannot be applied.

In the tensioner pulley structure shown in FIGS. 8.9 and 12 and 13, an eccentric hole is provided at a position eccentric from the rotation center of the rotating member of the fixing member, and the fixing tool is inserted through the eccentric hole. Since the fixing member is fixed, the fixing member is moved from the fixed position by the vibration transmitted from the belt and the force acting on the belt, and there is a disadvantage that the initial tension is reduced and the belt tension is reduced.

Moreover, the tensioner pulley structure shown in FIGS. 8 and 9 and FIGS. 12 and 13 has a problem that when the fixing member is fixed by the fixing member, the fixing member is rotated by the tightening rotational force of the fixing member. However, there is a disadvantage that the initial tension cannot be appropriately applied. In order to solve such a problem, 8.9
For the tensioner pulley structure shown in the figure,
As in the tensioner pulley structure shown in FIG. 13, it is necessary to provide a structure in which a locking plate is fixedly provided on a fixing member and the locking plate is fixed by a fixing tool. As a result, the number of parts increases as described above. There are inconveniences such as an increase in the size of the external shape and a large mounting space, and the vibration of the internal combustion engine causes parts such as the locking plate and the tension applying tool to be damaged and fall off, and are caught between the driving parts to damage the internal combustion engine. There is a risk.

[Object of the invention]

Therefore, an object of the present invention is to eliminate the need for a locking plate or a tension urging tool, to reduce the number of parts and cost, to achieve compactness, and to reduce the mounting space. It can prevent damage to the internal combustion engine due to breakage and dropout of the stop plate and tension urging tool, etc.Also, it can prevent sudden fluctuation of initial tension caused by variation of tension urging tool and set initial tension to predetermined It is an object of the present invention to provide a tensioner pulley structure for an internal combustion engine that can be applied and can prevent rotation of a fixing member during fixing and can appropriately apply an initial tension.

[Means for solving the problem]

In order to achieve this object, the present invention provides a rotating member provided rotatably on the outer periphery of a fixed member, and a pivot shaft at a position eccentric from the rotating member rotation center on one axial side surface of the fixed member. The eccentric hole to be fixed is provided, and an arc-shaped fixing tool insertion hole having the center of the eccentric hole as the center of rotation is provided so as to penetrate through each side in the axial direction of the fixing member, and on the other side in the axial direction of the fixing member. The fixing member is provided with an engaging hole in which the tension applying jig is engaged so as to coincide with the center of the eccentric hole on one side surface in the axial direction of the fixing member.

[Action]

According to the configuration of the present invention, since the tension applying jig is engaged with the engaging hole provided so as to coincide with the center of the eccentric hole to apply the initial tension, the conventional locking plate or tension urging tool, In addition, a fixture for fixing the locking plate can be eliminated. Also,
The tension urging tool can be dispensed with, and the tension applying jig rotates the fixing member around the center of the eccentric hole as the center of rotation to apply a predetermined initial tension, and then forms an arc with the center of the eccentric hole as the center of rotation. Is fixed by the fixing tool inserted into the fixing tool insertion hole, so that the initial tension caused by the variation of the urging force of the tension urging tool can be prevented from being changed suddenly, and the fixing member can be rotated at the time of fixing. Can be prevented.

〔Example〕

Next, an embodiment of the present invention will be described in detail with reference to the drawings.

1 to 7 show an embodiment of the present invention.
In FIG. 7, 2 is an internal combustion engine, 4 is a crankshaft, 6 is a crankshaft pulley, 8 is a camshaft, and 10 is a camshaft pulley. A timing belt, which is a toothed belt, is provided between the crankshaft pulley 6 provided on the crankshaft 4 of the internal combustion engine 2 and the camshaft pulley 10 provided on the camshaft 8 of the valve operating mechanism (not shown).
12 are rolled up. Also, this timing belt
Reference numeral 12 is also wound around an accessory pulley 14 and an idler pulley 16 of accessories (not shown). This timing belt
12 is tensioned by a tensioner 18.

The tensioner 18 has a shaft 20 as a fixed member and a pulley 22 as a rotating member, as shown in FIGS. A pulley 22 is mounted on the outer periphery of the shaft 20 as a bearing member.
It is rotatably mounted by 24 and is provided. This shaft
An eccentric hole 30 in which the swing shaft 28 is fixed is provided on one axial side surface 26 of the pulley 22 at a position eccentric from the rotation center C1 of the pulley 22. Further, the shaft 20 is provided with an arc-shaped insertion hole 32 having the center C2 of the eccentric hole 30 as the center of rotation and penetrating the axial side surfaces 26 and 34 of the shaft 20. In the insertion hole 32,
As shown in FIG. 6, a fixing bolt 36 as a fixing tool is inserted.

The other axial side surface 34 of the shaft 20 includes the shaft
An engagement hole 38 is provided so as to coincide with the center C2 of the eccentric hole 32 on one axial side surface 26 of the 20. The engagement hole 38 is engaged with a tension applying jig 40 shown in FIGS. Tension giving jig 40
Is provided with an engaging body 44 to be engaged with the engaging hole 38 at one end of the shaft-shaped rod 42, and a weight 46 for applying tension to the other end of the rod 42.

The tensioner 18 inserts the fixing bolt 36 into the insertion hole 32, and engages the engaging portion 44 of the tension applying jig 40 with the engaging hole 38 to apply the initial tension to the shaft 20 by the fixing bolt 36. It is fixed to the internal combustion engine 2 side.

More specifically, the swing shaft fixed to the eccentric hole 30 of the shaft 20
28 is attached to a mounting hole (not shown) on the internal combustion engine 2 side, and a fixing bolt 36 is inserted into the insertion hole 32 of the shaft 20 and temporarily tightened.
At this time, the fixing bolt 36 is tightened so that the shaft 20 can freely rotate, and the pulley 22 contacts the timing belt 12.

Next, as shown in FIG. 6, the engaging body 44 of the tension applying jig 40 is engaged with the engaging hole 38 of the shaft 20, and a predetermined initial tension F is applied by the weight 46 to tension the timing belt 12. . In this state, the crankshaft 4 is rotated to equalize the tension of the timing belt 12, and then the fixing bolt 36 is tightened to fix the shaft 20.

A predetermined tension is applied to the timing belt 12 to
After fixing, the engaging body 44 of the tension applying jig 40 is pulled out of the engaging hole 38 of the shaft 20.

Therefore, the tension applied to the timing belt 12 is determined by the weight 46 of the tension applying jig 40. Instead of the tension applying jig 40, a predetermined torque may be applied by a torque wrench to apply a predetermined tension to the timing belt 12.

In this embodiment, the tensioner pulley 18
Added tension to the toothed timing belt 12,
It is also possible to apply tension to a V-rib belt having V-ribs. In this case, a pulley 22 provided with a V-groove in the circumferential direction of the outer peripheral surface is rotatably provided on the outer periphery of the shaft 20.

As described above, since the tension applying jig 40 is engaged with the engaging hole 38 provided in alignment with the center C2 of the eccentric hole 30 to apply the initial tension, the conventional locking plate, tension urging tool, In addition, a fixture for fixing the locking plate can be eliminated. For this reason,
The cost can be reduced by reducing the number of parts.
Compactness can be achieved and installation space can be reduced. In addition, it is possible to avoid the possibility that the locking plate and the tension urging tool may be damaged or fall off due to the vibration of the internal combustion engine 2. The engine 2 can be prevented from being damaged.

In addition, the tension urging tool may be unnecessary, and the shaft 20 is fixed to the center of the eccentric hole 30 where the swing shaft 28 is fixed by the tension applying jig 40.
The eccentric hole having the center C2 of the eccentric hole 30 as the center of rotation is provided after rotating the center of rotation of the eccentric hole C2 to give a predetermined initial tension.
Since it is fixed by the fixing bolt 36 inserted in the arc-shaped insertion hole 32 provided through the axial side surfaces 26 and 34 of the shaft 20 at a distance from the shaft 30, it is caused by the variation in the urging force of the tension urging tool. It is possible to prevent the initial tension from being fluctuated and to apply the initial tension to a predetermined value.
Can be prevented from rotating unnecessarily, and a predetermined initial tension can be applied.

[Effects of the Invention] As described above, according to the present invention, the tension applying jig is engaged with the engaging hole provided in alignment with the center of the eccentric hole to apply the initial tension. And tensioning devices,
Fixtures and the like for fixing the locking plate can be eliminated.
For this reason, the number of parts can be reduced, the cost can be reduced, the size can be reduced, the mounting space can be reduced, and the risk of damage and dropping of the locking plate and the tension urging tool can be avoided. Thus, it is possible to prevent the internal combustion engine from being damaged by being caught between the drive components.

Further, the tension urging tool may be unnecessary, and the fixing member may be rotated around the center of the eccentric hole by the tension applying jig to apply a predetermined initial tension, and then the center of the eccentric hole may be set as the rotation center. Since it is fixed by the fixing tool inserted in the arc-shaped fixing tool insertion hole, it is possible to prevent the initial tension caused by the variation of the urging force of the tension urging tool, and to apply the initial tension to a predetermined value. The fixing member can be prevented from rotating unnecessarily during fixing, and a predetermined initial tension can be applied.

[Brief description of the drawings]

1 to 7 show an embodiment of the present invention. FIG. 1 is a front view of a tensioner, FIG. 2 is a longitudinal sectional view of the tensioner, FIG. 3 is a rear view of the tensioner, and FIG. , FIG. 5 is a plan view of a tension applying jig, FIG. 6 is an explanatory view when initial tension is applied by a tension applying jig, and FIG. 7 is a side view of an internal combustion engine with a tensioner attached. is there. 8 to 13 show a conventional example of a tensioner. FIGS. 8 and 9 are front and sectional views of a tensioner in which a locking plate for locking a tension urging tool is fixed to a fixing member. Front view and sectional view of a tensioner in which a locking plate for locking a tension urging tool is fixed to a fixing member and a fixing member insertion hole is provided in the fixing member;
12 and 13 are a front view and a sectional view of a tensioner provided with an engagement hole for engaging a tension applying jig at a position away from the center of the eccentric hole of the fixing member. In the figure, 2 is an internal combustion engine, 6 is a crankshaft pulley, 10
Is a cam shaft pulley, 12 is a timing belt, 18 is a tensioner, 20 is a shaft which is a fixed member, 22 is a pulley which is a rotating member, 24 is a bearing member, 26 is one axial side surface of the shaft 20, and 28 is a swing shaft. , 30 is an eccentric hole, 32 is an insertion hole, 34 is the other axial side surface of the shaft 20, 36 is a fixing bolt, 38 is an engaging hole, and 40 is a tension applying jig.

Claims (1)

(57) [Claims] An eccentric hole for fixing an oscillating shaft to a position eccentric from the rotation member rotation center on one axial side surface of the fixed member is provided on the outer periphery of the fixed member so as to be rotatable. In addition to this, an arc-shaped fixture insertion hole having the center of rotation of the eccentric hole as the center of rotation is provided so as to penetrate through each side surface of the fixing member in the axial direction, and the other side surface of the fixing member in the axial direction has one axial direction of the fixing member. A tensioner pulley structure for an internal combustion engine, wherein an engagement hole is provided in which a center of the eccentric hole on a side surface is engaged with a tension applying jig.