JPH10253480A - Shaking table for measuring unbalance - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make the spring constant small and reduce the effect of vertical support elastic bodies on a vibration system, by providing a vibrating body holding a measurement rotor supported on the vertical support elastic bodies and horizontal support elastic bodies and a vibration detector detecting the vibration of the vibrating body in the direction perpendicular to the protruding direction of the horizontal support elastic bodies via a connecting member. SOLUTION: Centrifugal force is generated by the unbalance of a rotor due to the rotation of the rotor, and a vibrating body 7 is vibrated in the lateral direction (x). The component in the longitudinal direction (y) of the generated vibration is constrained and neutralized by horizontal support elastic bodies 4a, 4b, 4c, 4d, and the component in the vertical direction, i.e., gravitational direction, of the vibration is neutralized by vertical support elastic bodies 6a, 6b. The vibration component only in the lateral direction (x) can be detected by vibration detectors 9a, 9b via a connecting member 8, and the dynamic unbalance of the rotor can be measured. Since the vertical support elastic bodies 6a, 6b suspended and support the vibrating body 7, the spring constant is made small, and the effect of the vertical support elastic bodies 6a, 6b on a vibration system can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an unbalance measuring vibration table mainly used for measuring unbalance of rotors of OA equipment, AV equipment and the like.

[0002]

2. Description of the Related Art In recent years, rotors used in OA equipment, AV equipment and the like have been required to have higher speed and lower vibration. Accordingly, high accuracy is also required for rotor unbalance measurement.

FIG. 4 shows an example of an unbalance measuring vibrating table. A work (rotating body to be measured) 51 such as a rotor is chuck-held on a work holding body 52, and the work holding body 52
Is fixed to the rotating body 55 such that the tester rotating main shaft 53 and the shaft 54 of the work 51 are coaxial. Rotating body 55
The tester rotating spindle 53, which is integral with the rotating shaft 53, is rotatably supported by the vibrating body 31 for unbalance measurement via a pair of upper and lower bearings 56, 57, and is rotated by the motor 59 via the transmission belt 60. Driven. Further, the vibrating body 31 is fixed to the tester main body 62 via a spring 61 such as a leaf spring, and vibrates due to a centrifugal force generated by an unbalance amount of the work 51. This vibration is detected by a vibration detector (not shown), and the unbalance amount of the work 51 is calculated (see Japanese Patent Publication No. 60-45816).

FIG. 3 shows another conventional example of an unbalance measuring vibration table in which the amount of unbalance of a rotating body to be measured can be measured by detecting the vibration of the vibrating body 31 in the x direction. ing. (Work 51, work holder 52,
The rotating body 55, the motor 59, and the conduction belt 60 are omitted. The shaking table for measuring unbalance includes an L-shaped bracket 50.
A horizontal support elastic body 32 protruding from the bracket 50 in the front-rear direction y, a vertical support elastic body 33 vertically supported on the floor of the support base, and the horizontal support elastic body 32 and the vertical support elastic body 33 A vibrating body 31 supported by the oscillating member and holding a workpiece such as a rotor to be measured;
And vibration detectors 37a and 37b that detect the vibration in the left-right direction x through the connecting member 36.

The horizontal support elastic body 32 comprises a pair of left and right upper horizontal bar springs 32a and 32b and a pair of left and right lower horizontal bar springs 32c and 32d. It comprises a pair of vertical rod-shaped spring bodies 33a, 33b arranged.

The operation of the vibration table for measuring unbalance in the above configuration will be described.

When the rotor is rotated (see FIG. 4), a centrifugal force is generated due to the imbalance of the rotor, and the centrifugal force causes the vibrating body 31 to vibrate in the left-right direction x. At this time, of the vibration generated in the vibrating body 31, the vertical direction, that is, the gravitational direction component is neutralized by the vertical rod-shaped spring bodies 33a and 33b. It is detected by upper and lower vibration detectors 37a and 37b. That is, the originally required dynamic imbalance of the rotor is measured.

[0008]

According to the conventional unbalance measuring vibration table shown in FIG. 3, a plurality of different frequency components are mixed in the entire system of the vibrating body 31 holding the rotor in the adjustment stage. Causes a measurement error. Therefore, it is necessary to vibrate the system of the vibrating body 31 at one frequency. However, the vertical rod springs 33a and 33b necessary to neutralize the gravitational component of the vibration components of the vibrator 31 support the own weight of the vibrator 31, so that it is difficult to adjust the spring constant. Body 33
a, the vibration of the system is disturbed by the influence of 33b.
Two sets of horizontal bar springs 32a, 3 supporting the vibrating body 31
The spring constant has been adjusted by changing the wire diameter of 2b, 32c, 32d, or by providing a notch, a step, etc. in the horizontal rod-shaped spring body, but this adjustment work is very difficult and requires a long time. There was a problem of cost.

Accordingly, an object of the present invention is to provide an unbalance measurement shaking table capable of solving the above-mentioned problems.

[0010]

In order to solve the above-mentioned problems, a vibration table for unbalance measurement according to the present invention comprises: a vertical support elastic body protruding downward from a support member; and a horizontal support elastic body protruding horizontally from a support member in a predetermined direction. A horizontal supporting elastic body, a vibrating body supported by the vertical supporting elastic body and the horizontal supporting elastic body and holding a rotating body to be measured, and the vibration in a direction orthogonal to a projecting direction of the horizontal supporting elastic body. A vibration detector that detects vibration of the body via the connecting member.

It is preferable that the present invention is configured such that the vibrating body supporting position of the horizontal supporting elastic body can be adjusted.

According to the above configuration, since the vertically supporting elastic body hangs and supports the vibrating body that holds the rotating body to be measured, its spring constant can be reduced, and the vertically supporting elastic body is connected to the vibration system. The effect can be reduced.
In addition, if the vibration support position of the horizontal support elastic body can be adjusted, the natural frequency of the vibration system can be easily adjusted in a short time.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an unbalance measuring vibration table according to a first embodiment of the present invention will be described with reference to FIG.

As shown in FIG. 1, the vibration table for measuring unbalance includes a bracket (support member) 2 having an L-shape in side view,
A horizontal support elastic body 4 composed of a total of four horizontal bar springs 4a, 4b, 4c, and 4d projecting horizontally forward from the bracket 2 and a pair of front and rear inverted L-shaped support brackets ( The vertical support elastic body 6 composed of vertical rod-shaped spring bodies 6a and 6b protruding downward from the support members 10 and 10, respectively, and supported by the horizontal support elastic body 4 and the vertical support elastic body 6 and the object to be measured. A vibrating body 7 (see FIG. 4) that holds a certain rotor, and a vibration in the x direction, which is a direction orthogonal to the projecting direction of the horizontal bar-shaped spring bodies 4a, 4b, 4c, and 4d of the vibrating body 7 in a horizontal plane,
A pair of upper and lower vibration detectors 9 that are detected via the connecting member 8
a and 9b.

Next, the operation of the vibration table for measuring unbalance in the above configuration will be described.

When the rotor (work) rotates, centrifugal force is generated due to imbalance of the rotor. With this centrifugal force, vibrator 7
Vibrates in the left-right direction x. That is, the components in the front-back direction y of the generated vibration are restrained and neutralized by the horizontal bar-shaped spring bodies 4a, 4b, 4c, and 4d, and the vertical direction of the vibration, that is, the gravity direction, is generated by the vertically supported bar-shaped spring bodies 6a and 6b. The components are neutralized, so that a vibration component only in the left-right direction x is transmitted through the connecting member 8 to the upper and lower vibration detectors 9.
a, 9b. The required dynamic imbalance of the rotor is thus measured.

By the way, the vertically supporting rod-shaped spring bodies 6a, 6b
Supports the vibrating body 7 so that the vibrating body 7 is suspended. In the support of the vibrating body 7, the vibrating body 7 does not tilt or fall due to lack of the spring constant of the vertically supporting rod-shaped spring bodies 6 a and 6 b. The spring constants of the bar-shaped spring bodies 6a and 6b can be reduced, and the influence of the vertically supported bar-shaped spring bodies 6a and 6b on the natural frequency of the vibration system can be reduced. Therefore, the natural frequency of the vibration system can be easily adjusted. can do.

Next, an imbalance measuring vibration table according to a second embodiment of the present invention will be described with reference to FIG.

As shown in FIG. 2, the vibration table for unbalance measurement has an L-shape in plan view and upper and lower brackets (support members) 22a, 22b arranged vertically.
A pair of left and right upper and lower horizontal bar spring bodies 24a, 24b inserted and held in the left and right insertion holes 23a, 23b, 23c, 23d of the brackets 22a, 22b so as to be horizontally movable in the front-rear direction y. 24c, 24
d and a pair of front and rear vertical L-shaped support brackets (support members) 30, 30 each having an inverted L-shape when viewed from the side.
6b, and a vibrating body 27 supported by the upper and lower horizontal bar springs 24a, 24b, 24c, 24d and the vertical bar springs 26a, 26b and holding a rotor to be measured. And the horizontal bar-shaped spring bodies 24a, 24b, 24c of the vibrating body 27,
It is composed of a pair of upper and lower vibration detectors 29a and 29b that detect, via the connecting member 28, vibrations in a direction orthogonal to the projecting direction of the 24d in the horizontal plane, that is, in the left-right direction x. The upper bracket 22a and the lower bracket 22b are configured to be movable in the front-rear direction y, and the vibrator supporting positions of the upper horizontal bar springs 24a, 24b and the lower horizontal bar springs 24c, 24d are adjustable. .

Next, the operation of the vibration table for measuring unbalance in the above configuration will be described.

When the rotor (work) rotates, a centrifugal force is generated due to imbalance of the rotor. With this centrifugal force, vibrator 2
7 vibrate in the left-right direction x. That is, the horizontal bar springs 24a, 24b, 24c, 24d
The component of the generated vibration in the front-rear direction y is restrained and neutralized, and the vibration component in the vertical direction, that is, the gravitational direction generated by the vertical support rod-shaped spring bodies 26a and 26b is neutralized. The vibration is detected by upper and lower vibration detectors 29a and 29b via the connecting member 28. The required dynamic imbalance of the rotor is thus measured.

When adjusting the natural frequency of the vibration system in this shaking table, the upper and lower brackets 22a,
2b is independently moved in the front-rear direction y to adjust the support position of the horizontal support rod-shaped spring bodies 24a, 24b, 24c, 24d. In this case, the movement of the brackets 22a and 22b is adjusted.

The adjustment of the natural frequency utilizes the fact that the spring constant of the rod-shaped spring body is proportional to the fourth power of the wire diameter and inversely proportional to the third power of the length. Thus bracket 2
By moving the 2a and 22b, the natural frequency of the vibration system can be easily finely adjusted, and the measurement accuracy of the unbalance can be improved. Further, in adjusting the natural frequency, the length of protrusion of the horizontal bar spring between the upper and lower portions of each of the horizontal bar springs 24a, 24b, 24c, 24d can be adjusted. The adjustment can be performed without any adjustment, and the adjustment time can be reduced. In addition, each horizontal bar-shaped spring body 24a, 24b, 24
It is also possible to configure all of the vibrator support positions c and 24d so as to be independently adjustable.

[0024]

As described above, according to the structure of the present invention, since the vibrating body that holds the rotating body to be measured is suspended by the vertically supporting elastic body, the spring constant of the vertically supporting elastic body in the vibration system is reduced. , The natural frequency of the vibration system can be easily adjusted, and the measurement accuracy can be improved.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a first embodiment of the present invention.

FIG. 2 is a perspective view showing a second embodiment of the present invention.

FIG. 3 is a perspective view showing a conventional unbalance measurement vibration table.

FIG. 4 is a sectional view showing another conventional example.

[Explanation of symbols]

 2 Bracket (supporting member) 4 Horizontal supporting elastic body 4a-4d, 24a-24d Horizontal bar spring 6 Vertical supporting elastic 6a, 6b, 26a, 26b Vertical bar spring 7 Vibrating body 8 Connecting member 9a, 9b, 29a, 29b Vibration detector 10, 30 Support bracket (support member) 22a Upper bracket (support member) 22b Lower bracket (support member) 51 Workpiece (rotary body to be measured)

Claims (2)

[Claims] 1. A vertical support elastic body projecting downward from a support member, a horizontal support elastic body horizontally projecting in a predetermined direction from the support member, and supported by the vertical support elastic body and the horizontal support elastic body. A vibrating body for holding the rotating body to be measured, and a vibration detector for detecting, via a connecting member, vibration of the vibrating body in a direction orthogonal to a projecting direction of the horizontal support elastic body. Shaking table for unbalance measurement. 2. The vibration table for unbalance measurement according to claim 1, wherein a vibration body supporting position of the horizontal support elastic body is adjustable.