JPS634838Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a belt tension adjustment device for easily and reliably adjusting the belt tension of an alternator attached to an internal combustion engine to a tension within a predetermined range.

Conventionally, an alternator rotation drive mechanism transmits the rotation of a crank pulley 1 to an alternator pulley 3 via a belt 5 wrapped around an alternator pulley 3 and a water pump pulley 4 of an alternator 2, as shown in FIG. It's becoming like that. In order for the alternator 2 and the water pump to function normally, it is necessary that the belt 5 be tensioned with an appropriate tension.

Conventionally, as shown enlarged in FIGS. 2 and 3, an alternator 2 is supported at its upper end by a bracket 6, and an alternator stay 7 extending downward from the lower end of the alternator 2 is fastened together with a slider 8 to an adjuster bar 9. It is supported by The alternator belt can be adjusted by rotating the slider 8, which is fastened together with the alternator stay 7 and the adjuster bar 9, with the tightening bolt 10 loosened, and the adjuster screw 11, which is screwed onto the slider 8. This is done by changing the support angle of the alternator.

However, in such conventional belt tension adjustment, the tension of the belt is often set by relying on human intuition, and it is difficult to adjust the tension within an appropriate range. In addition, if you try to set it quantitatively, it is necessary to measure the belt tension using a tension gauge and adjust it to the desired tension, which increases time loss and significantly reduces work efficiency. There was a problem. Furthermore, mechanically, the adjustment screw 11
Since the rotation of the adjusting screw 11 directly affects the belt tension, the belt tension changes greatly due to a slight rotation of the adjuster screw 11, and the belt tends to become over-tensioned. When over-tensioned, the overload will be applied to related parts and their supporting bearings.
This may cause durability problems.

In order to solve such problems, this invention
It is an object of the present invention to provide a belt tension adjustment device that can easily set the belt tension within an appropriate range without relying on intuition.

In order to achieve this purpose, in the belt tension adjustment device of the present invention, the alternator is swingably attached to the internal combustion engine, and the belt tension adjustment device is equipped with an alternator stay extending from the swinging end side. The alternator stay moving means for adjusting the position of the alternator stay is composed of a spring, a spring mounting bracket, and an adjuster bolt arranged in series in the moving direction. The spring has one end connected to the alternator stay side and the other end connected to the spring mounting bracket.
The spring mounting bracket is relatively rotatably attached to the adjuster bolt, and the adjuster bolt is rotatably attached to the adjuster bar. In addition, the spring mounting bracket can be adjusted by rotating the adjustment bolt by either screwing the adjustment bolt into the adjustment bar or by screwing the spring mounting bracket itself into the adjustment bolt. It is attached to the adjuster bolt so as to be movable in the axial direction of the adjuster bolt, that is, in the direction of movement of the alternator stay.

With such a structure, when the adjusting bolt is rotated toward the tightening side, the spring fitting moves along with the adjusting bolt or on the axis of the adjusting bolt in the belt tensioning direction. The spring mounting bracket is moved in the spring tensioning direction, but since the other end of the spring is connected to the alternator stay side, a tensile force corresponding to the belt tension transmitted from the alternator stay side is applied to the spring, and this The spring will stretch by an amount corresponding to the tensile force. Therefore, the belt tension can be determined by looking at the amount of spring expansion, and by adjusting the tightening of the adjustment bolt so that the amount of spring expansion is within the appropriate range, the belt tension can be adjusted within the appropriate range. Adjustments that conventionally relied on intuition can now be made easily and quantitatively.

In addition, the force for belt tension adjustment is transmitted via a spring instead of directly from the adjuster bolt as in the past, and the increase in the spring force of the spring relative to the displacement of the adjuster bolt is reduced. By taking advantage of the characteristic that the increase in belt tension with respect to displacement of the conventional adjusting bolt is much smaller, it is easy to finely adjust the belt tension by rotating the adjusting bolt, and the belt tension can be adjusted accurately. Can be adjusted to the range.

Preferred embodiments of the belt tension adjusting device of the present invention will be described below with reference to the drawings.

FIG. 4 shows a belt tension adjustment device according to a first embodiment of the present invention. In the figure, the structure up to the structure in which the alternator 2 is supported at the upper end by a bracket 6 and the tension of the belt 5 is adjusted by moving the alternator stay 7 along the adjuster bar 9 is the same as the conventional one.

However, in the present invention, the moving means 12 for moving the position of the alternator stay 7 includes a spring 13 and a spring mounting bracket 14 arranged in series in the moving direction A-B of the alternator stay 7, that is, in the direction along the adjuster bar 9. , and an adjusting bolt 15.

The spring 13 extends in the alternator stay movement direction AB, and one end thereof is connected to a pin 16 provided on the alternator stay 7, and the other end is connected to a spring mounting bracket 14. The spring fitting 14 is attached to the tip of the adjusting bolt 15 so as to be rotatable relative to the adjusting bolt 15, and the spring fitting 14 itself is restrained from rotating. The adjustment bolt 15 is screwed into the adjustment bar 9.
Adjustment bolt 15 by rotating
moves in the axial direction with respect to the adjustment bar 9.
Further, the spring mounting bracket 14 is configured to move together with the adjusting bolt 14 as the adjusting bolt 15 moves in the axial direction.

The operation of the belt tension adjusting device configured as described above will be described below.

By rotating the adjuster bolt 15, the adjuster bolt 15 moves in the B direction, that is, in the belt tensioning direction. Since the spring fitting 14 is attached to the tip of the adjusting bolt 15, the spring fitting 14 is also moved in the B direction. During this movement, the spring fitting 14 itself does not rotate because it is attached to be rotatable relative to the adjustment bolt 15 and rotation is restrained by the spring 13. When the spring mounting bracket 14 is moved, the spring 13 is pulled, and the spring 13
While stretching itself, the spring force is transmitted to the alternator stay 7, the alternator stay 7 is moved in the direction B, and the tension of the belt 5 is increased by the amount of movement. That is, since tension is applied to the belt 5 when the alternator stay 7 is pulled in the B direction by the spring 13, the spring 1
A belt tension is generated to balance the spring force of the spring 13, and there is a one-to-one correspondence between the spring force in a certain state of the spring 13 and the generated belt tension. On the other hand, the spring force and elongation of the spring 13 are in a proportional relationship, and the belt tension also corresponds to the elongation of the spring 13 on a one-to-one basis. Therefore, the belt tension can be determined by looking at the elongation of the spring 13, and the belt tension can be easily determined without measuring with a tension gauge as in the past. Since the belt can be tensioned using the adjuster bolt 15 while checking the belt tension, the belt tension can be easily set to the appropriate tension by first setting an appropriate extension amount of the spring 13 corresponding to the belt tension. It becomes possible.

In addition, in the past, the tightening force from the adjuster screw was directly transmitted to the belt 6 via the alternator stay 7, so the belt tension changed rapidly with a slight rotation of the adjuster screw, as shown in Figure 5. It exhibited the following characteristics. However, in the present invention, since the force is transmitted through the spring 13, a portion of the displacement of the adjusting bolt 15 and the spring mounting bracket 14 in the axial direction of the adjusting bolt due to the rotation of the adjusting bolt 15 is caused by the spring. It is absorbed by the elongation of 13. Therefore, the relationship between the rotational displacement of the adjusting bolt 15 and the belt tension is as shown in FIG. 6, and even if the adjusting bolt 15 is rotated to some extent, the belt tension does not vary greatly. Therefore, the belt tension can be finely adjusted by the adjuster bolt 15, and the belt tension is reliably and accurately adjusted to an appropriate range while being compared with the amount of extension of the spring 13.

Furthermore, the belt tension is adjusted while checking the elongation of the spring 13 as described above, but if a condition occurs where the predetermined elongation of the spring 13 cannot be obtained even if the adjustment bolt 15 is moved to the maximum, This indicates that the belt 5 has already stretched beyond a predetermined amount (predetermined belt elongation amount) before tension is applied, so the inability to adjust can be used as a sign of belt life and a guideline for the appropriate replacement time. It is also possible to do this.

Next, FIG. 7 shows a belt tension adjustment device according to a second embodiment of the present invention. In this example,
The spring mounting bracket 17 is the adjustment bolt 18
The adjusting bolt 18 is not screwed into the adjusting bar 9 but is simply rotatably supported. In such a device, by rotating the adjusting bolt 18, the nut 17 screwed into it is moved without moving the adjusting bolt 18 itself, and as the nut 17 moves, the spring 13 is pulled. The belt 5 is tensioned via the stretchable alternator stay 7. Other configurations and operations are similar to those of the first embodiment.

As explained above, when using the belt tension adjustment device of the present invention, the belt is tensioned via the spring by the rotation of the adjustment bolt, and the generated belt tension can be easily understood as spring elongation, and the adjustment The spring absorbs a portion of the displacement caused by bolt rotation, weakening the effect of displacement on belt tension and making it possible to finely adjust the belt tension. The effect can be obtained that it is possible to easily and quantitatively adjust the amount without relying on it, and also to be able to reliably and accurately adjust it within an appropriate range.

In addition, since the belt tension can be adjusted within a certain amount using the adjuster bolt, you can easily know when the belt has stretched beyond the specified amount even if adjustment is not possible, and when the belt reaches the end of its service life, the belt can be replaced. This also has the effect of being able to properly perform the following.

[Brief explanation of drawings]

Figure 1 is a front view of a conventional belt tension adjustment device.
2 is an enlarged front view of the device shown in FIG. 1, FIG. 3 is a plan view of the device shown in FIG. 1 near the adjuster screw,
FIG. 4 is a rear view of the belt tension adjusting device according to the first embodiment of the present invention, FIG. 5 is a characteristic diagram showing the relationship between the rotational displacement of the adjusting screw and the belt tension of the conventional device, and FIG. 6 4 is a characteristic diagram showing the relationship between the rotational displacement of the adjusting bolt and the belt tension of the device shown in FIG. 4, and FIG. 7 is a rear view of the belt tension adjusting device according to the second embodiment of the present invention. 2...Alternator, 5...Belt, 7...Alternator stay, 9...Adjustment bar, 12
...Transportation means, 13...Spring, 14, 17
...Spring mounting bracket, 15, 18...Adjustment bolt.

Claims (1)

[Scope of utility model registration request] Belt tension adjustment that adjusts the belt tension of an alternator that is attached to an internal combustion engine and supported so as to be swingable, by changing the position of an alternator stay that extends from the alternator to the swinging end side along an adjuster bar using a moving means. In the device, the moving means is arranged relative to a spring that extends in the direction of movement of the alternator stay and has one end connected to the alternator stay side and the other end connected to a spring mounting bracket, which is arranged in series in the direction of movement of the alternator stay, and an adjuster bolt. It consists of a spring mounting bracket that is rotatably attached, and an adjustment bolt that is rotatably attached to the adjustment bar and extends in the direction of movement of the alternator stay, and the spring attachment bracket is configured to screw the adjustment bolt to the adjustment bar. or by screwing the spring mounting bracket itself onto the adjusting bolt, so that it moves in the axial direction of the adjusting bolt as the adjusting bolt rotates, and the above-mentioned A belt tension adjustment device characterized in that a maximum movement distance of the spring mounting bracket due to rotation of an adjuster bolt is set to an amount corresponding to a predetermined constant elongation amount of the belt.