JPH11211623A - Dead room - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent contact between a power transmission shaft and a fixed soundproof sleeve when a prevention rubber is set between a bearing stand of a roller bearing of the power transmission shaft inserted to a soundproof wall and a foundation. SOLUTION: A power transmission shaft 10 inserted to a through hole 2a of a soundproof wall 2 of a dead room 1 is covered in a noncontact manner with fixed soundproof sleeves 19, 21, and supported rotatably by a roller bearing 17 supported by a bearing stand 14. The bearing stand 14 is set via a vibration- isolating rubber 13 to a base 12 mounted at a foundation 4 and a surface plate 11. Moreover, a stopper 24 is set to the bearing stand 14 to secure a gap to the surface plate 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an anechoic chamber used for a vehicle test apparatus and the like.

[0002]

2. Description of the Related Art For example, when measuring noise in a chassis dynamometer, a roller device for mounting wheels of a test vehicle is provided in a so-called anechoic chamber, and a dynamometer for driving and absorbing the power of the roller device is provided. Provided outside the room through a soundproof wall, the roller device and the dynamometer are connected by a power transmission shaft that has passed through the through hole of the soundproof wall,
A fixed soundproof sleeve for soundproofing is provided around the power transmission shaft. When the noise specification is severe, the power transmission shaft is supported by a low-noise hydraulic floating bearing, but in other cases, the power transmission shaft is supported by a rolling bearing.

[0003]

However, when the power transmission shaft is supported by the rolling bearings as described above, noise is generated on a foundation (particularly a surface plate) on which the bearing base of the rolling bearings is installed, and the noise is increased. Therefore, we installed anti-vibration rubber between the bearing stand and the foundation to prevent sound from affecting the foundation.
If the vibration-proof rubber becomes thin due to aging, there is a risk that the power transmission shaft and the fixed-side soundproof sleeve come into contact.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and a vibration-proof rubber is provided between a bearing base of a rolling bearing of a power transmission shaft and a foundation in order to prevent a sound from affecting the foundation. An object of the present invention is to provide an anechoic chamber that can prevent contact between a power transmission shaft and a fixed-side soundproof sleeve when provided.

[0005]

An anechoic chamber according to a first aspect of the present invention is supported by a bearing stand having a power transmission shaft inserted into a through hole provided in a surrounding soundproof wall and standing on a base side. In addition to being supported by rolling bearings, the periphery of the power transmission shaft is covered in a non-contact manner with a fixed-side soundproof sleeve, and vibration-proof rubber is provided between the bearing base and the base side, and a gap is provided between the bearing base and the base side. Having a stopper.

According to a second aspect of the present invention, the anechoic chamber detects that the gap becomes equal to or smaller than a predetermined value and generates an alarm.

[0007]

Embodiment 1 Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
1 and 2 show a front view and a plan view of a power test apparatus (chassis dynamometer) according to Embodiment 1, and FIGS. 3 and 4 are an enlarged vertical sectional front view and an enlarged side view of a rolling bearing portion. In the figure, reference numeral 1 denotes an anechoic room whose periphery is surrounded by a soundproof wall 2, and the outside of the soundproof wall 2 is a dynamo room 3. In the dynamo chamber 3, a dynamometer 5 is provided on a concrete base 4, and a rolling bearing 7 is provided via a bearing base 6. The rolling bearing 7 rotatably supports a connecting shaft 8. Connecting shaft 8
Is connected to a dynamometer shaft 5a via a flexible coupling 9.

On the other hand, a through hole 2a is provided in the soundproof wall 2 separating the anechoic chamber 1 and the dynamo chamber 3, and a power transmission shaft 10 having one end connected to the other end of the connecting shaft 8 is inserted into the through hole 2a. Is done. Reference numeral 11 denotes a surface plate buried in the foundation 4, and the surfaces of the foundation 4 and the surface plate 11 are flush with each other. 12 is basic 4
And a base mounted on a surface plate 11, and a base 14 of a bearing base 14 on a base 12 via a vibration-proof rubber 13.
a is placed. That is, both the base 12 and the base 14a have the same square shape, and the vibration isolating rubber 13 is provided at the four corners between them. Anti-vibration rubbers 15 are also placed at four corners on the base 14 a, and bolts 16 are inserted through the base 14 a and the anti-vibration rubbers 13 and 15 and fastened to the base 12. 1
Reference numeral 7 denotes a rolling bearing supported by a bearing base 14, which rotatably supports a connecting shaft 18. FIG.
3 and 15 show perspective views.

One end of the connection shaft 18 is connected to the other end of the power transmission shaft 10, and the other end of the connection shaft 18 is connected to a rotatably supported roller shaft, and the wheels of the vehicle under test are mounted on the rollers. Is placed. Reference numeral 19 denotes a fixed-side soundproof sleeve that is attached to the periphery of the through hole 2a and covers the periphery of the power transmission shaft 10 in a non-contact manner in the through hole 2a. Reference numeral 20 denotes a non-contact sleeve around the power transmission shaft 10 in the dynamo chamber 3. The fixed-side soundproofing sleeve 19 has one end attached to the fixed-side soundproofing sleeve 19. Reference numeral 21 also denotes a fixed-side soundproofing sleeve that covers the periphery of the power transmission shaft 10 in a non-contact manner in the anechoic chamber 1, one end of which is attached to the fixed-side soundproofing sleeve 19, and which is supported by a column 22 erected on the foundation 4. Is done. Reference numeral 23 denotes a support handle provided on each of the fixed-side soundproof sleeves 20 and 21. Reference numeral 24 denotes a stopper attached to both sides of the base 14a by bolts 25, and has a gap of 1 to 2 mm between the stopper and the surface plate 11.

In the above configuration, the dynamometer 5 drives or absorbs the power of the roller device provided in the anechoic chamber 1 via the power transmission shaft 10 and the like. In the anechoic chamber 1, the outer circumference of the power transmission shaft 10 is
21 to reduce noise. Further, an anti-vibration rubber 13 is provided between the base 12 and the base 14a,
The noise of the rolling bearing 17 is cut off by the vibration isolating rubber 13 and does not affect the surface plate 11. Further, when the anti-vibration rubber 13 is thinned due to settling, the stopper 24 comes into contact with the surface plate 11, so that the rotating shaft 10 and the fixed-side soundproof sleeve 21 do not come into contact with each other. When the stopper 24 comes into contact with the surface plate 11, sound is heard on the surface plate 11.
A thin liner made of a thin iron plate or brass may be inserted between the base plate 3 and the base 12 so that the stopper 24 does not abut on the surface plate 11. Is measured in advance, and the liner is inserted before abutment.

FIG. 6 is a front view of a main part of a power test apparatus according to a second embodiment. A proximity switch 26 is provided at a lower end of a stopper 24, and an alarm unit 27 is electrically connected to the proximity switch 26. .
Therefore, when the gap between the stopper 24 and the surface plate 11 becomes smaller than a predetermined value due to the settling of the vibration-proof rubber 13, the proximity switch 26 detects this and the alarm unit 27 generates an alarm. For this reason, before the stopper 24 comes into contact with the surface plate 11 to generate noise, the set of the vibration isolating rubber 13 can be detected and adjustment such as insertion of the liner can be performed, so that long-term noise is interrupted. Can be done without. Note that a limit switch may be provided instead of the proximity switch 26.

[0012]

As described above, according to the first aspect of the present invention, a stopper having a gap with the base side is provided on the bearing base provided with the vibration isolating rubber between the base side and the vibration isolating rubber. When the sag occurs, the stopper comes into contact with the base side, so that the contact between the power transmission shaft and the fixed-side soundproof sleeve can be prevented. Further, since a sound is generated when the stopper comes into contact with the base side, it is possible to detect the set of the vibration-proof rubber.
Further, it is possible to detect the degree of set of the vibration isolating rubber by the gap between the stopper and the base side.

According to the second aspect, an alarm is issued when the gap between the stopper and the base side becomes equal to or less than a predetermined value, so that a long-term noise test can be performed without interruption.

[Brief description of the drawings]

FIG. 1 is a front view of a power test device according to Embodiment 1 of the present invention.

FIG. 2 is a plan view of the power test device according to the first embodiment.

FIG. 3 is an enlarged longitudinal sectional front view of a rolling bearing portion of the power test device according to the first embodiment.

FIG. 4 is an enlarged side view of a rolling bearing portion of the power test device according to the first embodiment.

FIG. 5 is a perspective view of the soundproof rubber according to the first embodiment.

FIG. 6 is a front view of a main part of a power test device according to a second embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Anechoic chamber 2 ... Soundproof wall 2a ... Through-hole 4 ... Foundation 5 ... Dynamometer 11 ... Surface plate 12 ... Base 13, 15 ... Anti-vibration rubber 14 ... Bearing stand 17 ... Rolling bearing 19, 21 ... Fixed side soundproof sleeve 24: Stopper 26: Proximity switch 27: Alarm section

Claims (2)

[Claims] In an anechoic room surrounded by a soundproof wall, a power transmission shaft inserted from the outside into a through hole provided in the soundproof wall is supported by a rolling bearing supported by a bearing stand erected on a foundation side. In addition, the outer periphery of the power transmission shaft is covered in a non-contact manner by a fixed-side soundproof sleeve, a vibration-proof rubber is provided between the bearing base and the base side, and a stopper having a gap between the bearing base and the base side is provided. An anechoic room characterized by being provided. 2. The anechoic chamber according to claim 1, wherein when the gap becomes smaller than a predetermined value, an alarm is generated.