JPH0515585B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to a structure for reducing the rolling noise of rubber tires or the like on the vehicle side, and in particular, a structure that is attached to a lift lid to enhance the effect of reducing rolling noise. This invention relates to a tire noise reduction device.

[Background of the invention]

Conventional running noise reduction devices for monorail cars, as described in Japanese Patent Application Laid-Open No. 58-61062, reduce noise levels synthesized from the speed reducer, current collector, main motor, tires, etc. that make up the bogie's tire running system. For sound sources other than tires, there are those that absorb or emit sound, or that take measures against each source itself, but rubber tires require adhesive strength, and the number of tires per vehicle Due to the large number of tires, there was a problem in that tire rolling noise was not sufficiently reduced.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a tire noise reduction device that can effectively reduce noise caused by rolling of a rubber tire and suppress external noise from a wheel chamber.

[Summary of the invention]

The present invention provides a tire noise reduction device for a vehicle in which a running rubber tire is rotatably installed on a bogie frame and an underframe constituting a vehicle body is supported on the bogie frame, including the following: around the contact area between the rubber tire and the running road surface. and a lift lid attached to the underframe so as to be able to open toward the inside of the vehicle, the lid being disposed in an opening formed in the underframe in correspondence with the installation position of the rubber tire, and attached to the underframe so as to be openable toward the inside of the vehicle. a box-shaped perforated plate installed on the lower surface of the lift lid, formed along the outer periphery of the rubber tire, and covering the side surface of the rubber tire, with holes formed only on the surface facing the rubber tire; , a sound-absorbing material installed between the frying lid and the perforated plate; and a sound-insulating plate surrounding the perforated plate and the sound-absorbing material and installed on the frying lid. It is something.

[Embodiments of the invention]

Hereinafter, one embodiment of the present invention will be described with reference to the drawings.
The truck 1 includes rubber tires 2, a speed reducer 7, a truck frame 8, and the like. Reference numerals 3 to 5 designate plugs attached to the bogie frame 8 to prevent rubber tire noise from being radiated to the track girder 17. The plug 3 is a pillow beam portion of the bogie frame 8, the plug 4 is an end beam portion, and the plug 5 is a side beam portion. are provided in each. The wheel room surrounds the cart for soundproofing, and 15 is a sound-absorbing wall, 9 is an inspection lid having a sound-absorbing material on the inner surface, and 6 is a skirt with sound-absorbing material. 14 is a ceiling sound absorbing material on the lower surface of the underframe 16, and 10 is a lid placed for inspecting the rubber tires 2. The lift lid 10 is installed in an opening formed in the underframe 16 to match the installation position of the rubber tire 2, and is attached to the underframe 16 by a hinge or the like so that it can be opened toward the inside of the vehicle. A sound plate 12 and a perforated plate 13 are provided on the back side of the frying lid 10 facing the rubber tire 2, and the inner surface thereof is filled with sound absorbing material 11 with a predetermined gap. The perforated plate 13 is curved into an arc shape along the outer periphery of the rubber tire 2, and has a hat-like shape as a whole so as to cover the side surface of the rubber tire 2. The sound plate 12 is configured in a cap shape so as to completely cover the outer periphery of the perforated plate 13 and the sound absorbing material 11.

In the above configuration, noise generated when the bogie runs is restricted from being radiated outside the vehicle because the bogie 1 is surrounded by the sound-absorbing wall 15, the skirt 6, and the inspection lid 9. Since sound-absorbing materials are provided for each, sound reduction is achieved through sound absorption.

Regarding the rolling noise of the rubber tire 2, in the conventional case, that is, when the structure is not as in the above embodiment, there is a noise level difference of about 5 dB(A) between the rubber tire ground contact part and the circumferential part of the rubber tire. The noise level in the horizontal direction from the ground contact area was high, and the level in the vertical direction, that is, in the circumferential direction of the tire, was low. Therefore, simply placing the sound absorbing means on the ground above the rubber tire 2 will not provide a sufficient sound reduction effect. Therefore, in the embodiment, the sound generated on the road surface of the rubber tire 2 is suppressed by the plugs 3 to 3.
A perforated plate 13 is provided at the top of the rubber tire 2 in the circumferential direction, that is, at the position of the lift lid 10.
By installing a sound reduction means consisting of a sound absorbing material 11 and a sound absorbing material 11, efficient sound absorption is achieved. With this configuration, the average value of the sound pressure level at a 1 m radius from the road surface, that is, the ground contact surface of the rubber tire 2, is approximately
It can reduce noise by 10dB(A) and absorb sound very efficiently.

The perforated plate 13 has an arc shape along the outer diameter of the rubber tire 2 so as to increase the amount of incident noise, and furthermore, by selecting the hole size and hole pitch, resonance sound absorption is achieved by inhaling a specific frequency. Material 1
By changing the thickness of the material 1, noise frequencies over a wide range can be absorbed.

〔Effect of the invention〕

According to the present invention, by providing a suction and sound device on the back side of the lift lid located above the rubber tire for the purpose of tire inspection, in a state surrounding the rubber tire,
Since the high-level noise generated from the rubber tires can be absorbed, it has the effect of further reducing the sound radiated from the wheel chamber to the outside of the vehicle.

[Brief explanation of drawings]

FIG. 1 is a side view of a wheel chamber of a truck equipped with the device of the present invention, and FIG. 2 is a sectional view taken along line A-A in FIG. 1... Trolley, 2... Rubber tires, 3-5... Closure, 10... Lid, 11... Sound absorbing material, 12...
Shiyatone board, 13...Perforated board.

Claims (1)

[Scope of Claims] 1. A tire noise reduction device for a vehicle in which running rubber tires are rotatably installed on a bogie frame and an underframe constituting a vehicle body is supported on the bogie frame, comprising: a closure that surrounds the contact area and is attached to the bogie frame; and a closure that is placed in an opening formed in the underframe corresponding to the installation position of the rubber tire and is attached to the underframe so that it can be opened toward the inside of the vehicle. a box-shaped hole installed on the lower surface of the lift lid, formed along the outer periphery of the rubber tire, and covering the side surface of the rubber tire, with the hole formed only on the surface facing the rubber tire; a perforated board; a sound-absorbing material installed between the frying lid and the perforated board; and a sound-insulating board surrounding the perforated board and the sound-absorbing material and installed on the frying lid. Features: Tire noise reduction device.