JPH03223526A - Elastic shaft joint structure - Google Patents

Abstract

PURPOSE:To attenuate effectively vibrations in the swinging and axial directions by providing radially blades for regulating the relative rotational displacement between a piston rod and a housing on the outer periphery of a portion of the piston rod located in the housing. CONSTITUTION:Rotational torque is transmitted between an input shaft (joint tube) 2 and an output shaft 3 connected to each other through a rubber system elastic body 4. When a relative torsion angle is made between the input and output shafts, the rubber system elastic body 4 is flexed and also blades 12 radially provided on a piston rod 10 are rotatably displaced in silicon oil 8 within a housing 7 to function substantially as resistance plates for displaying a damping effect. The damping effect on the relative axial displacement between the input and output shafts 2, 3 is fulfilled between the silicon oil 8 within the housing 7 and piston 9. Thus, this device, when used for a drive system of a propeller shaft of a vehicle, can prevent the vehicle from vibrations.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to the structure of an elastic shaft joint, and more particularly to the structure of an elastic shaft joint suitable for use in a joint portion of a propeller shaft for a vehicle.

Conventional technology and its problems 1 The structure of a dual-use propeller shaft is such that both ends of the propeller shaft are connected to the universal joint on the other side via a rubber elastic body, in order to reduce vibrations caused by engine torque fluctuations. It is known (for example, Utility Model Application Publication No. 188016/1983).

In such a structure, when an excitation force due to torque fluctuations from the engine is applied, resonance occurs due to torsional vibration in which the propeller shaft itself is the mass and the rubber elastic body is the spring. Unless the constants are strictly controlled, a necessary and sufficient vibration damping effect will not be obtained, which will instead cause longitudinal vibration of the vehicle.

On the other hand, in order to suppress the longitudinal vibration of a vehicle as described above, a torsional vibration damping mechanism for a propeller shaft drive system has been proposed as Japanese Utility Model Application No. 61-57232. In this torsional vibration damping mechanism, the drive shaft is divided into two parts, an input end and an output side, and a hydraulic damper mechanism that acts in the direction of the drive shaft is provided between the two, and this hydraulic damper mechanism is connected to one of the two divided parts. The shaft is engaged with the other shaft through a spiral groove provided on the shaft, and the other shaft is engaged with the other shaft through a groove extending in the axial direction provided on the shaft. The torsion angle is absorbed as the stroke of the hydraulic damper, and in the absorption process, the torsional vibration of the drive system converted into axial displacement is damped by the damper effect.

However, in the structure of the above-mentioned torsional vibration damping mechanism, it is not only necessary to ensure a relatively large amount of overlap between the shaft at the input end and the shaft at the output side, but also because the structure is complicated.
The present invention was made in view of the above problems, which leads to an increase in f1ffi and makes it impossible to reduce the weight of the propeller shaft drive system.
The purpose is to provide an elastic shaft joint 4R structure that is particularly compact and has a simple structure, yet can effectively damp vibrations in the torsional and axial directions.

Means for Solving the Problems The present invention provides a human power shaft and an output shaft that are connected to each other via a rubber-based elastic body, and a shaft that is arranged concentrically with the shaft inside one of the shafts and has a predetermined shape inside. The piston is located within the housing to regulate relative displacement in the axial direction between the housing and the housing, and one end is connected to the other shaft. The piston rod includes a piston rod that is relatively movable in the axial direction and the rotational direction, and a vane that is provided radially around the outer periphery of a portion of the piston rod that is located inside the housing to restrict relative displacement in the rotational direction between the piston rod and the housing. .

According to this structure, rotational torque is transmitted between the input and output shafts via the rubber elastic body, but when a relative torsion angle occurs between the input and output shafts, the rubber elastic body bends and at the same time, The vanes provided on the piston rod are rotationally displaced in the fluid within the housing, and the vanes essentially function as a resistance plate, thereby exerting a damping effect in the rotational direction. This absorbs the relative torsional angle between the input and output shafts and attenuates torsional vibrations.

Furthermore, a damping effect is exerted between the fluid in the housing and the piston against relative displacement in the axial direction between the input and output shafts.

Embodiment FIG. 1 is a diagram showing an embodiment of the present invention, and shows an example in which the present invention is applied to a joint portion of a propeller shaft for a vehicle.

In Fig. 1, 2 is a joint tube as a human power shaft, 3 is an FRP shaft as an output shaft that is the center of the propeller shaft l, and joint tube 2 and shaft 3 are connected through a rubber elastic body 4. are integrally connected. The joint tube 2 is connected to an output shaft of a transmission on the engine side, and the shaft 3 is connected to a differential device on the drive wheel side via a predetermined joint member (not shown).

A housing 7 sealed with an auxiliary ring 5 and a rubber cover 6 vulcanized and bonded to the auxiliary ring 5 is fixed inside the shaft 3, and a predetermined fluid is contained inside the housing 7. For example, corn oil 8 is sealed. A piston rod 10 integral with a piston 9 is provided in the housing 7, and a piston port 10 protrudes from the cover 6 and is connected to the joint tube 2.

The piston rod 10 and the cover 6 are fixed to each other by, for example, vulcanization adhesive, and the piston rod 10 can be displaced in its axial direction and rotational direction by utilizing the deflection of the cover 6. ll is a sealant that seals the joint between the housing 7 and the auxiliary ring 5.

A plurality of blades 12 extending in the radial direction of the piston rod 10 are integrally formed in a radial direction in a portion of the piston rod 10 located inside the housing 7.As described later, when the housing 7 and the piston rod 10 rotate relative to each other, the blades 12 are formed integrally with the piston rod 10. 12 functions as a resistive plate, thereby exerting a damping effect.

Further, a ring-shaped plate 13 is integrally fixed to the outer circumference of the piston 9, and a minute gap 14 is formed between the inner wall surface of the nozzle 7 and the plate 13.

According to this structure, the rotational torque transmitted from the engine side to the joint tube 2 is transmitted to the shaft 3 via the rubber elastic body 4. During this transmission process, if a relative torsion angle occurs between the joint tube 2 and the shaft 3 due to irregular rotation on the engine side or rapid torque fluctuation, the piston rod lO integrated with the joint tube 2 bends the cover 6. rotationally displaced while rotating.

This rotational displacement absorbs the above-mentioned relative torsional angle, and since the vane 12 integrated with the piston rod 10 functions as a resistance plate in the silicone oil 8, the torsional vibration is attenuated by its damping effect.

In addition, when a vibration is input between the joint tube 2 and the shaft 3 that causes displacement in the axial direction, the stop rubber 15 attached to the inner surface of the joint tube 2 and the end surface of the shaft 3 While the piston 9 functions as a resistance plate and the silicone oil 8 moves through the minute gap 14, its damping effect dampens the vibration in the axial direction of the shaft 3. be done.

FIG. 2 shows another embodiment of the present invention, which differs from the first embodiment in that a joint tube 22 is disposed inside the shaft 3 as shown in the figure. In this embodiment as well, the same effects as in the first embodiment can be obtained.

Furthermore, in the one shown in FIG. 3, a cover 26 that seals the housing 7 is formed so that its cross section is bellows-shaped. In addition to the effects common to the above embodiments, this embodiment has the bellows shape of the cover 26, so that the strain on the cover 26 when the piston rod 10 is torsionally and axially displaced is reduced. This has the advantage of improving the durability of the cover 26 itself.

Effects of the Invention As described above, according to the present invention, although the structure is relatively small and simple, vibrations can be efficiently damped by the damping effect of the fluid, and it is particularly suitable for use in the drive system of the propeller shaft of a vehicle. In this case, vibrations in the torsional and axial directions of the propeller shaft, which cause vibrations in the longitudinal direction of the vehicle, can be significantly suppressed, and it can also contribute to reducing the weight of the drive system and, by extension, the vehicle.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of a main part showing one embodiment of the present invention, FIG. 2 is a cross-sectional view of a main part showing another embodiment of the present invention, and FIG. FIG. 2.22...Joint tube as input shaft, 3
...Shaft, 4...Rubber-based elastic body, 6.26...
- Cover, 7... Housing, 8... Silicone oil as fluid, 9... Piston, IO... Piston rod, 12... Vane. 2-1--Shaft Bamboo 1-F' 3-----Shaft 4-111 Gum Stiffness, Knee 5----n+Mom---Housing Link 8-1--Silicone 9 --- 1 stone 10 --- Dust 70-7 )- 12 --- 1 stone Kite

Claims (1)

[Claims] (1) An input shaft and an output shaft that are connected to each other via a rubber-based elastic body, and arranged concentrically with one of the shafts,
It has a sealed housing in which a predetermined fluid is sealed, and a piston that is located inside the housing to regulate relative displacement in the axial direction between the housing and the housing, and one end of which is connected to the other shaft. A piston rod that can be relatively displaced in the axial direction and rotational direction between the piston rod and vanes that are provided radially around the outer periphery of the portion of the piston rod that is located inside the housing to restrict relative displacement in the rotational direction between the piston rod and the housing. An elastic shaft joint structure characterized by comprising , and.