JPH04108403U - dynamic damper - Google Patents

Abstract

(57) [Summary] [Purpose] To reduce both the differential whine noise and muffled noise caused by bending resonance of the drive shaft in a vehicle. [Structure] A dynamic damper mounted on a drive shaft includes a first mass fixedly connected to the drive shaft, a plurality of arc-shaped bodies formed outside the first mass, and a plurality of arc-shaped bodies formed on the outside of the first mass. A second mass includes a leg piece that protrudes from the body and passes through a through hole provided in the first mass, and a magnet that is formed at the end of the leg piece and is attracted to the drive shaft. .

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

This idea was developed to reduce the differential whining noise caused by the bending resonance of the drive shaft in vehicles. The present invention relates to a structure that reduces both muffled sound and muffled sound.

0002

[Conventional technology]

Conventionally, in a front-wheel drive passenger car a as shown in FIG. A dynamic damper c is attached to the. In this figure, d is the engine, e indicates a transaxle, and f and g each indicate a wheel.

0003 In FIG. 4, which is an enlarged cross-sectional view taken along line A-A in FIG. A circular ring is attached to the shaft b via a plurality of elastic bodies h such as rubber extending in the radial direction. A shaft i is configured concentrically with the drive shaft b.

0004

[Problem that the idea aims to solve]

By the way, in front-wheel drive passenger cars, the bending resonance of the driveshaft causes a speed of 50 km/h. The hum of the differential at 100km/hr (for example, 500Hz) and the noise of the differential at 100km/hr While muffled sound (for example, 100Hz) is a problem, in the conventional configuration described above, The dynamic damper C installed on the drive shaft B is , it was only effective against the muffled sound at 100km/hr, so I changed this to 50km/hr. Structure effective for both humming noise at Km/hr and muffled noise at 100 Km/hr The challenge of this invention is to provide the following.

[0005]

[Means to solve the problem]

Here, this idea is applied to a dynamic system installed in a vehicle's drive shaft. A damper, which is connected concentrically to the drive shaft via an elastic body. and a first mass concentrically with the drive shaft outside the first mass. This second mass is composed of a plurality of arc-shaped bodies and these A leg piece that protrudes from the arc-shaped body and passes through a through hole provided in the first mass, and these leg pieces a magnet formed at the end of the drive shaft and attracted to it when the drive shaft rotates at low speed; This paper proposes a dynamic damper consisting of the following.

[0006]

[Effect]

In the dynamic damper of this invention with the above-mentioned structure, when running at low speed, Since the centrifugal force associated with the rotation of the driveshaft is relatively small, the second mass The magnets formed at the ends of the legs remain attached to the drive shaft, A dynamic damper uses only the elastic body and the first mass to respond to high frequencies (for example, 5 00Hz), but when the centrifugal force increases when driving at high speed, The magnet is displaced outwardly away from the driveshaft, where the dynamic damper is placed. is a low frequency (e.g. 100Hz) by the elastic body, the first mass and the second mass. ) is tuned.

[0007]

【Example】

Next, this invention will be explained with reference to FIGS. 1 and 2. In addition, the dynamic damper The mounting locations are the same as those shown in FIG. 3 in the description of the prior art.

[0008] First, in FIG. 1, the drive shaft 1 has a plurality of elastic pieces extending in the radial direction. An annular first mass 3 is connected to the drive shaft 1 via a (for example, rubber) 2. formed concentrically.

[0009] On the other hand, a structure is also arranged concentrically with the drive shaft 1 on the outside of the first mass 3. The second mass 4 is made up of a plurality of (four in the illustrated example) arc-shaped bodies 5 and a leg piece 7 that protrudes from and passes through a through hole 6 formed in the first mass 3; It is composed of magnets 8 formed on the inner ends of the pieces 7, and the magnets 8 are formed at the inner ends of the pieces 7. As shown in FIG. 1, the magnet 8 is attracted to the drive shaft 1, and 50 Reduces Km differential whine noise.

0010 When the drive shaft 1 rotates at high speed during high-speed driving, the magnet 8 , the centrifugal force applied to the second mass 2 becomes larger, and as shown in FIG. jumps out in the centrifugal direction, and the dynamic damper operates at a low frequency (e.g. 100Hz). It is possible to reduce the muffled sound by tuning. Note that the above embodiment is for a FF type passenger vehicle. Although we have explained the example of a car, it can be applied not only to passenger cars but also to trucks. For example, it can be applied to the front or rear axle of an all-wheel drive vehicle, or the rear axle of a rear-wheel drive vehicle. It is.

[0011]

[Effect of the idea]

According to the above-described structure of this invention, the first mass and centrifugal force reduce both humming noise at low speeds and muffled noise at high speeds. This provides a dynamic damper that can automatically respond to

[Brief explanation of drawings]

FIG. 1 is a sectional view of the dynamic damper of this invention in a first operating state.

FIG. 2 is a sectional view of the dynamic damper of this invention in a second operating state.

FIG. 3 is a schematic diagram showing the mounting position of a dynamic damper in a FF passenger car.

FIG. 4 is a sectional view of a conventional dynamic damper of this type.

[Explanation of symbols]

1 Drive shaft 2 Elastic piece 3 1st square 4 Second square 5 Arc-shaped body 6 Through hole 7 leg pieces 8 Magnet

Claims (1)

[Scope of utility model registration request] 1. A dynamic damper mounted on a drive shaft of a vehicle, the drive shaft comprising:
It consists of a first mass concentrically connected to the drive shaft via an elastic body, and a second mass configured outside the first mass concentrically with the drive shaft. a plurality of arcuate bodies, leg pieces protruding from these arcuate bodies and penetrating through holes provided in the first mass, and a leg piece formed at the end of these leg pieces and being attracted to the leg pieces when the drive shaft rotates at low speed. A dynamic damper consisting of a magnet.