JP2000329205A - Belt tension device for engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To downsize an engine by reducing projection of a tension device from an engine main body. SOLUTION: A moving body 15 is slidably fitted in a guide hole 19 of a pulley support part 16 provided on a front face of an engine main body 1. A tension pulley 13 is rotatably fitted around a support body 14 through a ball bearing 12. A thread part 14a is provided at the tail end of the support body 14 and a tool fitting bore 18 is provided on the front end of the support body 14. The tension pulley 13 is made in one body with the moving body 15 by tightening the thread part 14a of the support body 14 into a thread portion 15a of the moving body 15 with a hexagon wrench fitted into the tool fitting bore 18. Then, tension of a belt placed between a drive wheel and a driven wheel is adjusted by moving the tension pulley 13 along the guide hole 19.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a tension device for applying tension to a belt used in an engine.

[0002]

2. Description of the Related Art A drive wheel connected to a crankshaft and a driven wheel connected to a water pump and the like are arranged on the front surface of the main body of the engine described above. There is a belt in between.

An appropriate tension is applied to the belt by a tension device, and the tension device is attached to the engine body as follows, for example, as shown in FIG. That is, the pulley support (41) is fixed to the engine body (1) with bolts, and the pulley support
The (41) is provided with an elongated guide hole (42). Its guide holes (4
In 2), a support shaft body (44) for supporting the tension pulley (43) is slidably fitted (in the left-right direction in FIG. 3).

The tension pulley (43) is externally fitted to the support (44) via a bearing (45).
By tightening the nut (46) to the front end (upper side in FIG. 3) of 4), the tension pulley (43) is
(44) It is freely rotatable. Then, the tension pulley (43) slides along with the support shaft body (44) along the guide hole (42) of the pulley support member (41) (rightward in FIG. 3), and the tension pulley ( 43) Belt (48)
, The tension is applied to the belt (48). The support shaft (44) includes a spring (47)
Accordingly, the belt (48) is urged in a direction of increasing the tension (rightward in FIG. 3).

[0005]

In the above-mentioned conventional tension device, the nut (46) projects forward (upward in FIG. 3) of the tension pulley (43). For this reason, if an engine cooling fan or the like arranged in front of the engine body (1) is brought closer to the engine body (1) side to reduce the size of the engine, the cooling fan or the like interferes with the nut (46). Resulting in. That is, since the nut (46) protrudes, the cooling fan and the like are connected to the engine body.
As a result, it was difficult to reduce the size of the engine.

SUMMARY OF THE INVENTION It is an object of the present invention to reduce the amount of protrusion of a tension device from an engine main body and to reduce the size of the engine. Another object of the present invention is to prevent a member of a tension device from being loosened by rotation of a tension pulley. Further, it is another object of the present invention to further reduce the amount of protrusion of the tension device from the engine body, thereby further reducing the size of the engine.

[0007]

Means for Solving the Problems [Invention of claim 1] The invention of claim 1 is, for example, shown in FIG.
As shown in FIG. 2 and FIG. 2, the configuration is as follows. A drive wheel (7) and a driven wheel (8) are arranged on the engine body (1), a belt (9) is bridged between the drive wheel (7) and the driven wheel (8), and a tension pulley (13) is provided. In the tension device for an engine belt for applying tension to the belt (9) by using the above, a pulley support (16) is provided in the engine body (1), and a moving body is provided in a guide hole (19) provided in the pulley support (16). By fitting (15), the moving body (15) is configured to be movable along the guide hole (19), and the tension pulley (13) is rotatably supported on the support shaft (14), A screw portion (14a) is provided at one axial end of the shaft body (14), and a tool fitting hole (18) is recessed at the other axial end of the support shaft body (14). A tool is fitted into the hole (18), and the spindle (14) is turned, so that the screw (14a) of the spindle (14) and the moving body
By screwing the screw portion (15a) provided on the (15), the tension pulley (13) is moved via the support shaft (14) to the moving body (15).
And it is configured to be movable in the direction of increasing or decreasing the tension on the belt (9) along the guide hole (19).

[Invention of claim 2] The invention of claim 2 is the same as the above-mentioned invention of claim 1, but further configured as follows. When the spindle (14) rotates in the same direction as the rotation of the tension pulley (13), the thread (14a) of the spindle (14) is tightened into the thread (15a) of the moving body (15). In addition, a screw is formed between the threaded portion (14a) of the spindle (14) and the threaded portion (15a) of the moving body (15).

[Invention of claim 3] The invention of claim 3 is the same as the above-mentioned invention of claim 1 or 2, but further configured as follows. Guide hole (19) of pulley support (16)
The adjusting bolt (20) is arranged along with the adjusting bolt (20), and the adjusting bolt (20) is screwed into the screw portion (15b) provided on the moving body (15).
(20) is engaged with a pulley support (16) so that it can rotate while its movement in the axial direction is restricted.

[0010]

Operation and Effect of the Invention [Claim 1] The invention of the above-mentioned claim 1 has the following operation and effects as shown in FIGS. 1 and 2, for example. That is, a tool is fitted into the tool fitting hole (18) of the support body (14), the support body (14) is turned, and the screw portion of the support body (14) is rotated.
The tension pulley (13) is integrally connected to the moving body (15) via the support shaft (14) by screwing the (14a) into the screw portion (15a) of the moving body (15) and screwing it. . As a result, the tension pulley (13) moves the guide hole (19) of the pulley support (16).
Along the belt (9) in the direction of increasing or decreasing the tension. Then, by moving the tension pulley (13), the tension applied to the belt (9) by the tension pulley (13) is adjusted.

In the conventional tension device, the nut (46) for attaching the tension pulley (43) to the support shaft (44) protrudes forward from the tension pulley (43) as described above. On the other hand, according to the present invention (see FIG. 3), the tension pulley (13) can be attached to the support shaft (14) without a nut (see FIG. 1). In other words, according to the present invention, the protrusion of the tension device from the engine body (1) can be reduced by omitting the nut, and the engine cooling fan and the like can be brought closer to the engine body (1) by that much. As a result, the size of the engine can be reduced.

[Claim 2] The invention of claim 2 provides the following functions and effects in addition to the functions and effects of the invention of claim 1.
It works. With the rotation of the drive wheel (7), the tension pulley (13) rotates via the belt (9),
The rotational force of the tension pulley (13) is transmitted to the support shaft (14). On the other hand, the support shaft (14) is
When rotating in the same direction as the rotation of (13), the threaded portion (14a) of the spindle (14) is screwed into the threaded portion (15a) of the moving body (15), so that the tension pulley (13) rotates. By the spindle (1
4) and the moving body (15) are screwed more firmly. As a result, it is possible to reliably prevent the support shaft (14) from loosening and coming off the moving body (15).

[Claim 3] The invention of claim 3 has the following operation and effect in addition to the operation and effect of the invention of claim 1 or 2. When the adjustment bolt (20) is turned,
The moving body (15) is screwed and the guide hole (19) of the pulley support (16)
Move along. That is, the tension of the belt (9) can be adjusted by rotating the adjustment bolt (20). And since the installation space of the adjusting bolt (20) is small, the tension device can be downsized.
Therefore, the amount of protrusion of the tension device from the engine main body (1) can be further reduced, and as a result, the engine cooling fan and the like can be brought closer to the engine main body (1) side, whereby the size of the engine can be reduced.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a belt tension device used in an engine according to the present invention will be described below with reference to FIGS. FIG. 1 is a sectional view taken along line II of FIG. 2 showing a main part of the tension device,
FIG. 2 is a front view showing a main part of the engine. In the following description, a diesel engine is taken as an example.

As shown in FIG. 2, a cylinder head (3) is provided above a cylinder block (2) in an engine body (1).
And a head cover (4) is attached above the cylinder head (3). An oil pan (5) is attached to the lower side of the cylinder block (2).
On one side (left side in FIG. 2) of the oil pan (5),
An oil supply unit (30) for supplying lubricating oil into the oil pan (5) is provided. A drive wheel (7) connected to a crankshaft (6) and a driven wheel (8) connected to a water pump (not shown) and the like are arranged on a front surface of the engine body (1). A belt (9) is stretched between the driving wheel (7) and the driven wheel (8). In addition, the engine body
A tension device (11) is arranged on the front surface of (1), and tension is applied to the belt (9) by the tension device (11).

The tension device (11) is configured as follows, as shown in FIG. That is, the tension device (11) includes a support shaft (14) that rotatably supports the tension pulley (13) via a ball bearing (12), and a support (14) that moves the support shaft (14). And a pulley supporting portion (16) for guiding the tension of the belt (9) in the increasing / decreasing direction (the horizontal direction in FIG. 1). The pulley support (16) is
It is fixed to the front of (1) with bolts (see FIG. 2).

A tool fitting hole (18) is recessed at the axial front end (upper side in FIG. 1) of the support shaft (14). The tool fitting hole (18) is formed, for example, as a hexagon hole into which a hexagon wrench [tool] can be fitted. On the other hand, the spindle (1
An external thread (14a) formed on the left-hand thread is provided at the axial rear part (lower side in FIG. 1) of 4).
At the front part (upper side in FIG. 1) of (15), a female screw part (15a) formed on the left-hand thread is provided. And the support shaft (14)
By fitting the hexagon wrench into the tool fitting hole (18) and turning the support shaft (14) counterclockwise, the male screw portion (14a) of the support shaft (14) It is screwed into the female screw part (15a) of (15). Thereby, the support body (14) and the moving body (1
5) are integrally connected, and the inner ring (12a) of the ball bearing (12) is provided with a flange portion (14b) provided at the front end of the support shaft body (14).
It is sandwiched between the collar (24) arranged on the front side of the moving body (15).

The driving wheel (7) rotates rightward in FIG. 2, and accordingly, the tension pulley (13) rotates leftward. Therefore, the rotation of the tension pulley (13) transmits a leftward rotational force to the spindle (14) via the ball bearing (12), and the leftward rotation causes the spindle ( The thread (14a) of the left-hand thread of (14) is about to be screwed into the thread (15a) of the moving body (15). That is, the rotation of the tension pulley (13) causes the support shaft (14) and the movable body (15) to be screwed more firmly, and the support shaft (14) can be reliably prevented from being loosened.

An elongated guide hole is provided in the pulley support (16).
(19) is provided, and the moving body (15) is provided in the guide hole (19).
Is fitted so as to be freely slidable (left and right in FIG. 1). Further, through-holes (21) and (21) are provided on both sides (the left and right sides in FIG. 1) of the pulley support portion (16), and adjustment bolts (21) and (21) are provided in the through-holes (21) and (21). 20) penetrates sideways. Then, an intermediate part of the adjusting bolt (20) is formed into a female screw part formed laterally on the moving body (15).
(15b).

Further, one end of the adjusting bolt (20) [FIG.
On the right side, a pair of lock nuts (22) and (22) are fixed, and these lock nuts (22) and (22) are used in the axial direction of the adjustment bolt (20) (in FIG. 1, in the horizontal direction). When the adjustment bolt (20) is turned while restricting the movement to
0) does not fall out of the through hole (21). Further, a lock nut (23) is screwed into the other end (the left side in FIG. 1) of the adjusting bolt (20). The inner diameters of the through holes (21) (21) are larger than the outer diameters of the adjustment bolts (20). In other words, the adjustment bolt (20) is rotatable while its movement in the axial direction is regulated.
It is supported [engaged] by the pulley support (16).

The tension device (11) operates as follows. For example, when the belt (9) is extended due to long-term operation of the engine, the tension of the belt (9) is adjusted to be appropriate as follows. That is, using a tool or the like, loosen the lock nut (23) and turn the bolt head (20a) of the adjustment bolt (20) to move the moving body (15)
It is slid along the guide hole (19) integrally with the support shaft (14) by the screw action, and moves the tension pulley (13) to the side where the tension of the belt (9) increases (to the right in FIG. 2). Move. After the tension adjustment of the belt (9) is completed, the lock nut (23) is tightened to stop the adjustment bolt (20) from rotating, and the tension pulley (13) is locked.

Further, when replacing the belt (9), the lock nut (23) is loosened and the bolt head (20a) of the adjustment bolt (20) is turned to turn the tension pulley (13) to the tension of the belt (9). Move to the decreasing side (left side in FIG. 2). Then
The belt (9) is loosened and the belt (9) can be replaced. After the belt replacement, the tension pulley (1
3) Move the belt (9) to the side where the tension of the belt (9) is increased.
Adjust the tension of (9). After the tension adjustment of the belt (9) is completed, the adjustment bolt (20) is stopped from rotating as described above.

The bolt head (20) of the adjusting bolt (20)
a) is a side surface (1a) for maintenance of the engine body (1) among front, rear, left, right, and upper and lower side surfaces of the engine body (1).
[Left side in FIG. 2] side. That is, on the side of the maintenance side (1a), the oil supply unit (30), the fuel injection pump (31), the fuel injection nozzle (32)
And a starter (33) are arranged.
From the maintenance side (1a) side, maintenance such as lubricating oil supply into the oil pan (5), inspection of the fuel injection pump (31), etc. can be performed, and the adjustment bolt (20)
By turning, maintenance such as adjustment of the tension of the belt (9) and replacement of the belt can be performed.

The above embodiment can be modified as follows. That is, in the above description, the tool fitting hole (18) of the support shaft body (14) is formed in a hexagonal hole so that a hexagon wrench, which is a general tool, can be fitted. For example, the tool fitting hole (18) may be formed in a cross shape or a negative shape.
It may be concave in a letter shape, or may be a square hole or a pentagonal hole. In the above description, the screw portion (14a) of the support shaft (14) is a male screw, and the screw portion (15
Although a) was formed as a female screw, the present invention is not limited to this.
The screw portion (15a) of (15) may be formed in a male screw.

Further, in the above description, the tension pulley (13) pushes the outer peripheral surface of the belt (9) to push the belt (9).
The tension is applied to the belt 9, but the invention is not limited to this. The tension pulley 13 may press the inner peripheral surface of the belt 9 to apply tension to the belt 9.
In this case, since the tension pulley (13) rotates rightward, the male screw portion (14a) of the support shaft (14) and the moving body (1) are rotated.
The female screw portions (15a) of (5) are formed as right-handed screws, respectively, to prevent the support shaft (14) from loosening.

In the above description, the adjusting bolt (20)
The support (14) is slid to adjust the tension of the belt (9). However, the present invention is not limited to this. For example, the support (14) is connected to the belt (9) by a spring. The tension may be applied to the belt (9) by urging the belt (9). Further, the application of the present invention is not limited to a diesel engine, but is also applicable to a gasoline engine or the like.

[Brief description of the drawings]

FIG. 1 shows an embodiment of a belt tension device used for an engine according to the present invention, and is a cross-sectional view taken along line II in FIG. 2 showing a main part of the tension device.

FIG. 2 is a front view showing a main part of the engine.

FIG. 3 is a view corresponding to FIG. 1 showing a conventional tension device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Engine main body, 7 ... Drive wheel, 8 ... Follower wheel, 9 ... Belt, 13 ... Tension pulley, 14 ... Support shaft, 14a ... Screw part of support shaft, 15 ... Moving body, 15a ... Screw of moving body Part, 15b ...
Screw part of moving body, 16 ... pulley support part, 18 ... tool fitting hole,
19 ... guide hole, 20 ... adjustment bolt.

Claims (3)

[Claims] 1. A drive wheel (7) and a driven wheel on an engine body (1).
(8), an engine that extends a belt (9) between the driving wheel (7) and the driven wheel (8), and applies tension to the belt (9) with a tension pulley (13). In the tension device for a belt for a vehicle, a pulley support (16) is provided on the engine body (1), and a moving body (15) is fitted into a guide hole (19) provided in the pulley support (16). The movable body (15) is configured to be movable along the guide hole (19), and the tension pulley (13) is rotatably supported on the support shaft (14), and the support shaft (14) Threaded part (14a) at one axial end
And a tool fitting hole (18) is recessed at the other axial end of the spindle (14), and a tool is fitted into the tool fitting hole (18) so that the spindle is (14)
Turn the screw (14a) of the support shaft (14) and the moving body.
By screwing a screw portion (15a) provided on (15), the tension pulley (13) is integrated with the moving body (15) via the support shaft (14), and A tension device for an engine belt, wherein the tension device is configured to be movable in a direction of increasing or decreasing the tension applied to the belt (9) along the guide hole (19). 2. The tensioning device for an engine belt according to claim 1, wherein when the support shaft (14) rotates in the same direction as the rotation of the tension pulley (13), the support shaft (14) is rotated. So that the screw portion (14a) is screwed into the screw portion (15a) of the moving body (15),
A tension device for an engine belt, wherein a screw is formed between a screw portion (14a) of the support shaft (14) and a screw portion (15a) of the moving body (15). 3. The tensioning device for an engine belt according to claim 1, wherein the adjusting bolt is provided along a guide hole (19) of the pulley supporting portion (16).
(20) is arranged, and the adjusting bolt (20) is screwed into a screw portion (15b) provided on the moving body (15), and the adjusting bolt (20) is
The engine tensioning device for an engine belt according to claim 1, further comprising engaging the pulley supporting portion (16) so that the shaft can be rotated in a state in which movement in the axial direction is restricted.