JPH02125142A - Power transmitting system - Google Patents

Abstract

PURPOSE:To absorb the fluctuation of the engine rotation and improve the durability of a belt by elastically fixing between at least one of pulley main bodies on the driving side and the driven side and a rotary shaft via a coil spring. CONSTITUTION:The sliding member 7 of a pulley 1 is slidably inserted into a step 10 provided on the engine side of a rotary shaft 3 via a washer 11 and fixed with a stop ring 15 via a washer 14. A spring supporter 5 is inserted into a step on the side opposite to the engine of the rotary shaft 3 via a spline 8 and fixed with a stop ring 9. A coil spring 6 is arranged between the pulley 1 and the supporter 5, both ends are fixed with spring fixing sections 4, the pulley 1 and the rotary shaft 3 are elastically coupled, the fluctuation of the engine rotation is absorbed by the coil spring 6, and the vibration transmission to a belt 2 wound on the pulley 1 is prevented. The life of the belt is extended, and the occurrence of noise can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a power transmission system that transmits the output rotation of an engine of an automobile or the like to an auxiliary machine by means of a belt drive.

(Prior art) When the output rotation of the engine is transmitted to auxiliary equipment by belt drive, the belt is hung around a pulley piece that is completely fixed to the drive shaft and driven shaft to transmit the power, but the output rotation of the engine is There is rotational fluctuation. In particular, the rotational fluctuations of a diesel engine during idling are severe, and the tension on the belt also fluctuates greatly, significantly affecting the durability of the belt. Furthermore, when a load is connected, rotational fluctuations result in torque fluctuations for the engine, which puts a strain on the engine.

Furthermore, mechanical vibrations were generated, which caused noise.

Therefore, as a countermeasure against mechanical vibration, a method has been proposed in which an elastic pair made of rubber or the like is provided in a pulley type to absorb vibration and prevent noise (Utility Model Application No. 62-96
(See Publication No. 155).

(Problem to be solved by the invention) However, although the interposition of an elastic body such as rubber absorbs vibrations and plays a role in noise prevention, it is insufficient to absorb tension fluctuations on the belt and torque fluctuations on the engine. Moreover, in the case of rubber, there are significant changes over time such as the rubber wearing out and deterioration due to internal heat generation as it continues to be used. In addition, since rubber is interposed between the part where the belt is suspended and the rotating shaft, due to the structure, the running axis of the belt may shift slightly due to the rubber part, which affects power transmission efficiency and belt durability. Was.

It is an object of the present invention to solve the above-mentioned problems and provide a power transmission system that improves belt durability, reduces mechanical vibrations, and suppresses noise without placing a burden on the engine.

(Means for Solving the Problems) In order to achieve the above object, the present invention provides pulleys on each of the drive shaft and the driven shaft, a belt is hung between both pulleys, and power is transmitted from the drive shaft to the driven shaft. In a power transmission system, a pulley is rotatably attached to a rotating shaft but not movable in at least one axial direction, and the pulley is rotated via a coil spring on a spring support fixed to the rotating shaft. The present invention is characterized in that at least one of the drive shaft and the driven shaft is provided with a structure that is elastic in the direction and fixed so as to be pushed toward the side that cannot be moved in the axial direction.

(Function) As described above, by fixing the pulley and the rotating shaft via the coil spring, even if the rotation of the rotating shaft fluctuates, the fluctuation is absorbed by the coil spring, causing tension fluctuations on the belt and torque fluctuations on the engine. is alleviated.

(Example) Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

In Fig. 1, a coil spring as shown in Figs. 2 and 3, which will be explained later, is attached to the drive shaft (3).
A pulley (1) is provided between the driven shaft (12
) has a pulley (13) fixed to it. By using such a power transmission system, even if there are rotational fluctuations in the engine (not shown) that rotates the drive shaft (3), the fluctuations are absorbed by the coil spring, and tension fluctuations on the belt (2) are alleviated. Ru. Although Fig. 1 shows an example in which only the drive shaft pulley is provided elastically with respect to the shaft, it would be even more effective if the driven shaft side to which the auxiliary equipment (not shown) is connected has a similar structure. be. However, if it is provided on one side, it is preferable to provide it on the drive side connected to the engine in order to absorb engine rotation fluctuations before transmitting them to the belt.

Next, a structure for elastically fixing the rotary shaft pulley via a coil spring will be described in detail.

In Fig. 2, the pulley (10) is movable in the rotational direction with respect to the rotating shaft (3), and in the axial direction, a step (10) is provided on the engine side of the rotating shaft (3) to prevent it from moving in one direction in the axial direction. 1), and a belt (2) is suspended in the V-groove of the pulley (1). The pulley (1) is provided with a sublink fixing part (4), and the sublink fixing part (
A spring support (5) is fixed to the rotating shaft (3) so as to face the rotation shaft (3) by a spline, a key (8), and a stop ring (9).

Then, the coil spring (6) is fixed to the pulley (1) and the spring support (5), so that the pulley (1)
) is elastically fixed to the spring support (5) and the rotating shaft (3).

Further, the part of the pulley (1) that forms the groove is a pressed product made of metal, and the part that slides on the rotating shaft (3) uses a sliding member (7) made of metal or resin. Pulley (
1) has a stepped portion (10) and a washer (14) in the axial direction.
It is fixed via a stop ring (15). Regarding the stepped portion (10) side, if the sliding member (7) is made of resin, a washer (11) should be interposed to prevent wear due to sliding of the sliding member (7) with the stepped portion (10). is preferred.

Also, if the coil spring (6) is strong enough, the washer (14) on the spring side and the stop ring (15)
does not need to be provided.

In addition, coil springs (
6) uses a spring whose elastic strain energy is higher than the maximum energy imparted to the coil spring (16) by vibrations due to engine rotational fluctuations, which corresponds to the yield point specific to the coil spring (16) used.

If it is a low coil spring (6)
is not suitable for use because it is in a yield state. Further, coil springs whose yield point is too high depending on various conditions such as the rotational speed of the shaft and the mass of the pulley are also undesirable because the effect of vibration absorption is weak. In addition, the shape of the coil spring (6) is
It is not limited to a flat cylindrical shape, it can be anything like a drum-shaped one with a swollen central part, the reverse drum-shaped one, or a conical shape whose diameter increases toward one side. The cross-sectional shape is not limited to circular, but oval, rectangular, etc. may also be used. Furthermore, compared to elastic bodies such as rubber, coil springs have a wider range of elasticity that can be changed by changing the length, number of turns, and thickness of the spring, so it is possible to use coil springs with more suitable elasticity.

In addition, organic materials such as rubber tend to creep due to stress, generate internal heat due to alternating loads that occur during running, and are not only prone to elastic deterioration but also have low stress-bearing capacity, so their ability to conduct high torque is limited. be. On the other hand,
In the case of metal springs, under the conditions of use within allowable stress, they hardly cause any creep, etc., have good resistance to heat, and can exhibit long life and reliable performance.

Further, as shown in FIG. 3, the pulley (1) is not limited to a V-type pulley, but may be a rib pulley, or may be a toothed pulley, although not shown. However, since transmission by a toothed belt requires synchronous transmission, the elasticity must be low so as not to affect synchronism, even if it sacrifices some vibration absorption effect. The pulley (1) shown in Figure 2 is made of a metal plate bent into a shape that allows the coil spring (6) to be stored under the groove, allowing for a compact design. However, it is of course possible to use a conventional disc-shaped pulley as shown in Fig. 3, and the pulley (1) is attached to the rotating shaft (3) so as to be slidable in the rotational direction. ,
A spring fixing part (4) is provided on the side of the pulley (1).
), the spring support (5) is set as a rotating shaft (3) using a spline or key (8), and the two are connected by a coil spring (6), so that the pulley (1) rotates 4 degrees. It is elastically fixed to the shaft (3).

(Effect) In a power transmission system in which a pulley is provided on the drive shaft and a driven shaft, a belt is hung between both pulleys, and power is transmitted from the drive shaft to the driven shaft as in the present invention. By using a structure in which at least one of the pulley bodies and the rotating shaft is elastically fixed via a spring, even if the rotation of the drive side engine changes, the fluctuation is absorbed by the coil spring, and the fluctuation to the belt is absorbed. ,
Torque fluctuations to the engine are alleviated, and the durability of the belt can be improved. Furthermore, since the mechanical vibrations caused by the above-mentioned fluctuations are also alleviated, it is possible to suppress the noise caused by the mechanical vibrations.

[Brief explanation of the drawing]

FIG. 1 is a side view showing an embodiment of the power transmission system of the present invention, and FIG. 2 is a sectional view taken along line A-A in FIG. )・(2)・(3)・(4)・(5)・(6)・(7)・Pulley belt rotating shaft spring fixing part spring support body coil spring sliding member

Claims (1)

[Claims] 1. In a power transmission system in which a pulley is provided on the drive shaft and a driven shaft, a belt is hung between both pulleys, and power is transmitted from the drive shaft to the driven shaft. The pulley is attached so as not to be movable in at least one direction, and the pulley is fixed to a spring support fixed to the rotating shaft so as to be elastically pushed in the rotational direction via a coil spring and pushed toward the non-movable side in the axial direction. What is claimed is: 1. A power transmission system characterized in that a structure formed by the above is provided on at least one of a drive shaft and a driven shaft.