JPH0522899U - Vibration control device for propeller shaft - Google Patents

Abstract

(57) [Abstract] [Purpose] It is possible to absorb two or more resonance vibrations with different frequencies without increasing the man-hours for mounting the vibration damping device itself and without making the hollow shaft of the propeller shaft longer than necessary. And [Structure] Inside the cylindrical outer inertia body 3 mounted in the hollow portion of the propeller shaft via the outer elastic body 6,
The columnar inner inertial body 4 was concentrically attached via the inner elastic body 5, and the natural frequencies of the outer inertial body 3 and the inner inertial body 4 were made different.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a propeller shaft vibration damping device, and more particularly to a vibration damping device mounted inside a hollow shaft of a propeller shaft in a power transmission system of an automobile or the like.

[0002]

[Prior Art]

 Conventionally, as this type of vibration damping device, for example, the one disclosed in Japanese Utility Model Laid-Open No. 58-81128 is known.

This vibration damping device has one cylindrical inertial body (in the publication, “support ring”) having an outer diameter smaller than the inner diameter of the hollow shaft of the propeller shaft, and attached to the outer peripheral portion of the inertial body. And a cylindrical elastic body (in the publication, “vibration damping body”), the vibration damping device itself is hollowed by pressing the outer circumferential surface of the elastic body against the inner circumferential surface of the hollow shaft. It is designed to be installed inside the shaft.

In such a vibration damping device, when the propeller shaft resonates at the natural frequency of the inertial body, the resonance vibration is absorbed.

[0005]

[Problems to be solved by the device]

 However, since the above conventional vibration damping device is provided with only one inertial body, there is inevitably only one resonance vibration frequency that can be damped, and two or more resonance vibrations of different frequencies are inevitably generated. Could not be absorbed.

In addition, when a plurality of vibration damping devices each including one inertial body having a different natural frequency are prepared and these are mounted inside the hollow shaft of the propeller shaft side by side in the axial direction, The number of man-hours for mounting the vibration damping device increases, which leads to an increase in the price of the entire propeller shaft, and the hollow shaft must have a length longer than a predetermined length, which causes a problem of design restriction.

An object of the present invention is to propel a propeller shaft capable of absorbing two or more resonance vibrations having different frequencies without increasing the number of mounting steps and without making the hollow shaft of the propeller shaft longer than necessary. Is to provide a vibration damping device.

[0008]

[Means for Solving the Problems]

 The propeller shaft vibration damping device of the present invention is configured such that a plurality of inertial bodies having different natural frequencies are concentrically arranged around the axis of the hollow shaft inside the hollow shaft that constitutes the propeller shaft through elastic members. In addition, an elastic body is provided between these inertial bodies.

[0009]

[Action]

 In the vibration damping device for a propeller shaft according to the present invention, a plurality of inertial bodies and elastic bodies having different natural frequencies constitute a so-called dynamic damper, and absorbs a plurality of resonance vibrations having different propeller shaft frequencies.

Further, the number of steps for mounting the vibration damping device is not increased, and the design constraint on the length of the hollow shaft of the propeller shaft is eliminated.

[0011]

【Example】

 An embodiment of the present invention will be described below with reference to the drawings.

In the figure, reference numeral 1 denotes a hollow shaft of a propeller shaft, which is connected to a power transmission system by attaching a yoke member for a joint (not shown) to each of both ends 1A, 1A thereof.

In the case of this example, the end portion 1A of the hollow shaft 1 is drawn inward and then joined to the yoke member. As a result, the diameter of the yoke member has been reduced, and the joint, and hence the entire propeller shaft, have been made lighter, which makes it possible to respond to high-speed rotation of the propeller shaft.

As for the amount of reduction of the end portion 1A to the hollow shaft 1, for example, the outer diameter is reduced by about 10% in the portion of the range L _{1 that is} 20 to 30 mm from the end edge 1B of the hollow shaft 1, and the range is further reduced. The outer diameter is reduced from 10% to 0% in the range L ₂ from L ₁ to 30 to 50 mm. Then, from that range L _2, there is no restriction, and the outer diameter is the same as the intermediate portion. The two-dot chain line in the figure represents the end 1A before the drawing process.

Reference numeral 2 denotes a vibration damping device, which is mounted inside the hollow shaft 1 before the end 1A of the hollow shaft 1 is drawn. In the vibration damping device 2, 3 is a cylindrical outer inertial body whose outer diameter is smaller than the inner diameter of the hollow shaft 1, and 4 is a cylindrical inner inertial body whose outer diameter is smaller than the inner diameter of the outer inertial body 3. , The masses of these inertial bodies 3 and 4 are different from each other.

The inner inertia body 4 has two annular inner elastic bodies 5 attached to the outer peripheral portion thereof, and is further inserted inside the outer inertia body 3. The outer peripheral portion of the inner elastic body 5 is attached to the inner peripheral portion of the outer inertial body 3 by means such as pressure bonding or adhesion. Further, three annular outer elastic bodies 6 are attached to the outer peripheral portion of the outer inertial body 3. Therefore, the vibration damping device 2 has a structure in which the inner inertial body 4, the inner elastic body 5, the outer inertial body 3, and the outer elastic body 6 are concentrically assembled from the center toward the outside.

Then, such a vibration damping device 2 is inserted into the hollow shaft 1 before the end portion 1A is drawn, and the outer peripheral portion of the outer elastic body 6 is pressed or bonded by a means. And is attached to the inner circumference of the hollow shaft 1. Therefore, the end 1A of the hollow shaft 1 is drawn after the vibration damping device 2 is attached.

Thus, the vibration damping device 2 mounted inside the hollow shaft 1 constitutes a so-called dynamic damper by the inertial bodies 3 and 4 and the elastic bodies 6 and 5, and the propeller shaft has a natural frequency of each of the propeller shafts. It will absorb the resonance vibration. The inertial frequencies of the inertial bodies 3 and 4 are set to optimum values according to their masses and the spring constants of the elastic bodies 5 and 6, and the natural frequencies of the inertial bodies 4 and 5 are different in advance. Set to a value.

After all, the vibration damping device 2 absorbs two resonance vibrations having different frequencies.

It should be noted that the inner inertial body 4 has a cylindrical shape, and another cylindrical or columnar inertial body is concentrically mounted inside the inner inertial body 4 via an elastic body, so that three resonance vibrations of different frequencies are generated. Can be absorbed. In this way, two or more resonant vibrations of different frequencies can be absorbed depending on the number of deployed inertial bodies.

[0021]

[Effect of the device]

 As explained above, since the propeller shaft damping device of the present invention is configured to concentrically include a plurality of inertial bodies having different natural frequencies via elastic bodies, the number of deployed inertial bodies is Accordingly, a plurality of resonance vibrations having different propeller shaft frequencies can be absorbed.

Moreover, it is possible to eliminate the design man-hours regarding the length of the hollow shaft of the propeller shaft without increasing the man-hours for mounting the vibration damping device.

[Brief description of drawings]

FIG. 1 is a half sectional view showing an embodiment of the present invention.

[Explanation of symbols]

 1 hollow shaft 2 damping device 3 outer inertial body 4 inner inertial body 5 inner elastic body 6 outer elastic body

Claims (1)

[Scope of utility model registration request] 1. Inside a hollow shaft constituting a propeller shaft, a plurality of inertial bodies having different natural frequencies are concentrically arranged around an axis of the hollow shaft via an elastic member, and A vibration damping device for a propeller shaft, characterized in that an elastic body is provided therebetween.