JPH11142275A - Balance testing machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate the need to prepare a weigher separately from a balance testing machine in the case where the balance testing machine finds the axial position of the center of mass of a rotary body, to easily measure static loads on both ends of the rotary body while it is supported by the balance testing machine, and to speedily, accurately, and securely find the axial position of the center of mas of the rotary body according to the measured static loads. SOLUTION: The balance testing machine is equipped with rotary body support parts 2 and 3 which support the rotary body 6 rotatably at an interval along the axis of rotation of the rotary body 6 and load detecting means 4a, 4b, 4c, and 4d, and 5a and 5b which detect the static loads of the rotary body 6 applied on the respective rotary body support parts 2 and 3 by the rotary body support parts 2 and 3 while the rotary body 6 is supported by the rotary body support parts 2 and 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a balance testing machine capable of properly and quickly performing a balance test on a rotating body.

[0002]

2. Description of the Related Art Conventionally, when performing a balancing test using a rotating body as a test object, the rotating body is rotatably supported around a rotation axis and rotated, and the rotating body is rotated by centrifugal force acting on the rotating body. The magnitude of the unbalance of the rotating body is checked by the vibrating force or motion detected by the unbalance detecting unit to grasp the distribution state of the mass of the rotating body. And usually, according to the magnitude of the unbalance of the rotating body, mass is added to the rotating body such that the magnitude of the unbalance of the rotating body is within the maximum allowable residual unbalance. By removing the mass from a part of the rotating body, the mass distribution of the rotating body is adjusted, and the balancing with the rotating body is performed.

When a rotating body or a rotor is balanced as a rigid rotor, the maximum allowable residual unbalance as described above, that is, the allowable residual unbalance or allowable unbalance is determined by Japanese Industrial Standard JIS-JIS.
It can be determined according to the standard defined in B0905.

[0004] In determining the allowable residual unbalance of the rotating body, according to the use of the rotating body as a rotating machine and the required accuracy, a balancing is performed in accordance with the grade table of the good balance exemplified in the Japanese Industrial Standard JIS-B0905. A grade of goodness is determined, and an upper limit value of goodness of balance is set according to the determined goodness of balance. The grade of the good balance is defined as G0.4, G1, G2.5, ..., G4000. For example, if the grade of the good balance is determined to be G6.3, the upper limit of the good balance is 6.3. mm / s.

[0005] The allowable residual ratio imbalance refers to an amount obtained by dividing the magnitude of the allowable residual imbalance by the mass of the rotating body.
Rotating body balance and practical rotation speed n (min ^-1 )
Is given, a known graph, that is, the value of the practical rotation speed n (min ^-1 ) is plotted on the horizontal axis, and the value of the allowable residual ratio imbalance eper (μm) is plotted on the vertical axis. Practical rotational speed n (mi
n ^-1 ) optimal allowable residual ratio unbalance eper (μm)
According to the graph showing the value of, the allowable residual ratio imbalance can be immediately obtained.

As described above, the allowable residual ratio imbalance epe
Once r (μm) is obtained, this allowable residual ratio imbalance eper
By multiplying the value of (μm) by the mass m (kg) of the rotator, the allowable residual unbalance of the rotator is Upper = eper · m
(G · mm).

By the way, when a plane perpendicular to the rotation axis of the rotator on which the unbalance is corrected in the rotator is defined as a correction plane, in the case of a rotator having one correction plane,
The allowable residual unbalance of the correction surface is equal to the allowable residual unbalance of the rotating body, but in the case of a rotating body having two correction surfaces, the allowable residual unbalance Uper is determined by the allowable residual unbalance of the first correction surface. It is necessary to distribute the residual unbalance Upper1 and the allowable residual unbalance Upper2 of the second correction surface.

In the case of a rotating body having two correction surfaces, the allowable residual unbalance Upper is distributed between the allowable residual unbalance Upper 1 of the first correction surface and the allowable residual unbalance Upper 2 of the second correction surface. In doing so, the above Japanese Industrial Standard JIS
-Allocated as follows in accordance with the provisions of B0905.

First, as shown in FIG. 3, for example, when the rotating body 7 satisfies the following condition, ie, the center of mass S of the rotating body 7 determines the distance between the bearings R ₁ and R _2. In the middle part when divided into three,
In the two modifications surfaces A and balancing plane B is between the two bearing R ₁ and bearing R ₂ together, 1/3 1 times the balancing plane A, the distance b is bearing R ₁ between B, the distance between the R ₂ L (L / 3 ≦ b ≦ L), and the ratio of the distance h ₁ from the center of mass S of the rotating body 7 to the correction plane A to the distance h ₂ from the center of mass S to the correction plane B is 3 / 7 or more and 7/3 or less (3 /
7 ≦ h ₁ / h ₂ ≦ 7/3), the allowable residual unbalance Upper1 of the first correction surface A is distributed according to the equation (1).
The allowable residual unbalance Upper2 of the second correction surface B is [Equation 2].
Allocated by formula.

[Equation 1] Upper1 = (h ₂ / b) · Uper

[Number 2] _{Uper2 = (h 1 / b)} · Uper = (h 1 / h 2) · Uper1

[0010] Second, the center of mass S of the rotating body is the bearing R ₁ ,
It is in the middle part when the distance L between R ₂ is divided into three equal parts,
When the two correction surfaces A and B are located outside the bearings R ₁ and R ₂ , the distance from the center of mass S of the rotating body to the correction surface A is h _1, and the distance from the center of mass S of the rotating body is When the distance to the balancing plane B and h _2, the allowable residual unbalance Uper1 the first balancing plane a is distributed by [expression 3] where permissible residual unbalance Uper2 the second balancing plane B is [number 4 ] Expression.

[Number 3] _{Uper1 = (h 2 / b)} · (L / b) · Uper

[Number 4] _{Uper2 = (h 1 / b)} · (L / b) · Uper = (h 1
/ H ₂ ) ・ Uper1

Third, when the distance b from the correction surface A to the correction surface B of the rotating body is smaller than _１ ／ of the distance L between the bearings R ₁ and R ₂ (b <L / 3), the allowable residual is not sufficient. divided the balance in the balance static or quasi imbalance and偶不, in the case of static or quasi-static imbalance is first modified modified surface plane a, the distance in the middle of B from bearing R ₂ positions c 3 or one or both of the correction planes A and B. In the case of even imbalance, the correction planes are distributed to the correction plane A and the correction plane B.
However, in that case, the allowable residual unbalance U of the first correction surface A
per1 and the allowable residual unbalance Upper of the second correction surface B
2 is distributed according to the equation (5), and the allowable residual unbalance Upper3 of the third correction surface C is distributed according to the equation (6).

## EQU5 ## Upper1 = Uper2 = (Uper / 2)） (3L)
/ (4b)｝

[Equation 6] Uper3 = (Uper / 2) ｛{L / (2c)}

[0012] Fourth, as shown in FIG. 4, for example, when the rotating body 8 that does not belong to any of the case of the first case to third, and one reference bearings the bearing R _1, all the direction toward the dimension from the reference bearing other bearing R ₂ represents a positive, sequentially modified surface a two balancing plane in that direction, and balancing plane B. Also, from the reference bearing R ₁ to the bearing R ₂
The distance to the L, and the distance to the balancing plane A from quasi bearing R ₁ a, the distance from the modified surface A to modify surface B b, the reference bearing R
The distance from _one to the center of mass S s, h ₁ the distance from the modified surface A to the center of mass S, the distance from the center of mass S to modify surface B and h _2. In this case, the allowable residual unbalance Upper1 of the corrected surface A is the minimum absolute value of the values U'per1 calculated by the formulas [7] to [10], and the allowable residual unbalance of the second corrected surface B is The residual unbalance Upper2 is represented by [Equation 11].
To be distributed by

U′per1 = Uper · [(kL) / {(L−a) + R
(L-ab)｝]

U′per1 = Uper · [(kL) / {(L−a) −R
(L-ab)｝]

U′per1 = Uper · [(L−k) L / {a + R (a
+ B)｝]

U′per1 = Uper · [(L−k) L / {a−R
(A + b)｝]

Where k represents the proportion of the dynamic load applied to the two bearings R ₁ and R ₂ that can be shared by the reference bearing R ₁ , and the axial position of the center of mass S of the rotating body is R is the ratio between the allowable residual unbalance of the correction surface B and the allowable residual unbalance of the correction surface A, and if the position in the axial direction of the center of mass S of the rotating body is known, then ] Equation.

K = (L−s) / L where 0.3 ≦ k ≦ 0.7

R = h ₁ / h ₂ where 0.5 ≦ R ≦ 2

[0013]

As described above, when performing a balancing test on a rotating body, when the rotating body has two correction surfaces, the allowable residual unbalance Upper of the rotating body is considered. To the allowable residual unbalance Upper1 for the first correction surface and the allowable residual unbalance Upper2 for the second correction surface, in which case the axial position of the center of mass S of the rotating body is I needed to know. Conventionally, in order to know the position of the center of mass S of the rotating body in the axial direction, if the calculation is possible, the position of the center of mass S of the rotating body in the axial direction is calculated only by calculation, or the structure of the rotating body is complicated. In the case of, based on the weight load at both ends of the rotating body measured using a weighing scale prepared separately from the balance tester, the axial position of the center of mass S of the rotating body is calculated, or When an approximate value can be used, the approximate value is used as a numerical value indicating the axial position of the center of mass S of the rotating body.

However, the axial position of the center of mass S of the rotating body can be calculated only by calculation.
Only when the shape and structure of the rotating body are very simple, and when the shape and structure of the rotating body become complicated, it is difficult to obtain the axial position of the center of mass S of the rotating body only by calculation. When calculating the axial position of the center of mass S of the rotating body based on the weight load at both ends of the rotating body measured using a weighing scale separately prepared from the balancing tester, A separate weighing scale must be prepared,
When the rotating body becomes large and the weight becomes large, a great deal of time and labor is spent for measuring the weight load at both ends of the rotating body using a weighing scale. Further, an approximate value can be used as a numerical value indicating the position of the center of mass S of the rotating body in the axial direction, only when the shape and structure of the rotating body are relatively simple. Not only is it difficult to set an approximate value when is complicated, but also the calculated value of the allowable residual unbalance of each correction surface is the approximate value used as a numerical value indicating the axial position of the center of mass of the rotating body, In some cases, the reliability is not always sufficient.

Therefore, the present invention enables the position of the center of mass of the rotating body in the axial direction to be accurately and reliably obtained even if the shape and structure of the rotating body are complicated. This eliminates the need for a weighing scale, and even if the rotating body is large and heavy,
With the rotating body supported by the balancing tester, the static load at both ends of the rotating body can be easily measured, and based on the measured static loads at both ends of the rotating body, quickly, accurately and reliably. It is an object of the present invention to provide a balance testing machine that can determine the axial position of the center of mass of the rotating body.

[0016]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, a balancing tester according to the present invention is a balancing tester for performing a balancing test on a rotating body, wherein the balancing testing machine comprises the rotating body. A plurality of rotator support portions rotatably supporting the rotator at positions spaced apart from each other in the rotation axis direction of the rotator, and the respective rotator support portions in a state where the rotator is supported by the rotator support portions Load detecting means for detecting the magnitude of the static load of the rotating body applied to each of the rotating body supporting portions each time.

[0017]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a conceptual side view of a balancing tester according to one embodiment of the present invention, and FIG. 2 is a side view of a rotating body supported by the balancing tester according to the embodiment of FIG.

First, in FIG. 1, a balancing tester includes a plurality of rotating body supporting portions that rotatably support a rotating body 6 as a test object at positions spaced from each other in the direction of the rotation axis of the rotating body 6. The vibration gantry 2 and the vibration gantry 3 are provided. Strain gauges 4a and 4b as load detecting means are disposed on the side surface of the vibration gantry 2, and the base end of the vibration gantry 2 is placed on the base, that is, the bed 1, via a load meter 5a as the load detecting means. Supported. A bearing R ₁ is provided at the tip of the vibration gantry 2. On the other hand, the vibration mount 3
Strain gauges 4c and 4d as load detecting means
Is disposed, and the base end of the vibration gantry 3 is supported on the base, that is, on the bed 1 via a load meter 5b as load detecting means. A bearing R ₂ is disposed at the tip of the vibration gantry 3.

In the balancing tester shown in FIG. 1, the strain gauges 4a, 4b, 4c and 4d and the load meters 5a and 5b are used as load detecting means, but the strain gauges 4a, 4b, 4c and 4d are used as load detecting means. You can use only
Only the load meters 5a, 5b may be used. If the load detecting means can detect the load applied to each of the vibration gantry 2, 3, the strain gauges 4a, 4b, 4c, 4d and the load meters 5a, 5b may be used. Instead, any other load detecting means can be used.

When performing a balance test using the rotating body 6 as a test object using the balancing tester shown in FIG.
Are supported by bearings R ₁ and R ₂ , respectively. At this time, as shown in FIG. 2, static load P ₁ exerted by the rotating body 6 in bearing R ₁ are detected by the strain gauges 4a, 4b and load meter 5a as a load detecting means through the vibration cradle 2. On the other hand, static load P ₂ applied from the rotary body 6 in the bearing R ₂ are detected by the strain gauge 4c, 4d and load meter 5b as load detecting means via the vibration platform 3.

In FIG. 2, two correction surfaces of the rotating body 6 are referred to as correction surfaces A and B, and a surface passing through the center of mass S of the rotating member 6 and perpendicular to the rotation axis of the rotating member 6 is referred to as a surface C. , the distance from one bearing R ₁ to the other bearing R ₂ L, a distance from the bearing R ₁ to the surface C s, the distance from the bearing R ₁ to modify surfaces a a, balancing plane B from the modified surface a Where b is the distance from the correction surface B and c is the distance from the correction surface B to the bearing R ₂ , the expression [14] holds.

S · P ₁ − (L−s) · P ₂ = 0 where L = a + b + c According to the equation (14), the distance from the bearing R ₁ to the surface C, that is, the distance between the bearing R ₁ and the rotating body 6 The distance s to the center of mass S can be determined as in [Equation 15].

S = {P ₂ / (P ₁ + P ₂ )} · L where L = a + b + c

In the balancing tester shown in FIG. 1, calculation and detection accompanying the detection of the static loads P ₁ and P ₂ by the load detecting means such as the strain gauges 4a, 4b, 4c and 4d and the load meters 5a and 5b. Bearing R based on the determined static loads P ₁ and P ₂
Calculation of the distance s from ₁ to the center of mass S of the rotating body 6, the distance s from the calculated bearing R ₁ to the center of mass S of the rotating body 6
Is used to determine the allowable residual unbalance Upe of the first correction surface A.
r1 and the allowable residual unbalance Upper2 of the second correction surface B
The operation of calculating the value of can be performed by a computing device of a computer as a series of operations.

In the balance tester shown in FIG. 1, when performing a balance test on a rotating body, the rotating body 6 supported rotatably around the rotation axis by the bearings R ₁ and R ₂ is rotated by the rotation axis. By rotating it around and detecting the oscillating force or movement acting on the position of the correction planes A and B of the rotating body 6 by the centrifugal force acting on the rotating body 6 at that time, the unbalance detecting means (not shown) detects The magnitude of the imbalance of the rotating body 6 is detected, and the distribution state of the mass of the rotating body 6 is grasped. Then, according to the magnitude of the unbalance in each of the correction surfaces A and B of the rotating body 6, the magnitude of the unbalance at the position of each of the correction surfaces A and B is the maximum allowable residual unbalance, that is, At the position of the first correction surface A, the allowable residual unbalance is set to be within the value of the allowable residual unbalance Upper1, and at the position of the second correction surface B, the allowable residual unbalance Upper is set.
By adding mass to the rotating body 6 or removing mass from a part of the rotating body so as to be within the value of 2, the mass distribution of the rotating body is adjusted, and balancing with the rotating body is performed. .

[0024]

According to the balance testing machine of the present invention, there is provided a balance testing machine for performing a balance test on a rotating body, wherein the balancing testing machine mutually connects the rotating body in the rotation axis direction of the rotating body. A plurality of rotator support portions rotatably supported at positions spaced apart from each other, and each rotator support portion is applied to each rotator support portion while the rotator is supported by the rotator support portions. Since there is provided a load detecting means for detecting the magnitude of the static load of the rotating body, it is not necessary to prepare a weighing scale separately from the balancing test machine, and the shape and structure of the rotating body are complicated. It is also possible to accurately and reliably determine the axial position of the center of mass of the rotating body, and even if the rotating body has a large size and a large weight, it is supported by a balancing tester for any rotating body. The static at both ends of the rotating body Weight can be measured, and based on the measured static load at both ends of the rotating body, the position of the center of mass of the rotating body in the axial direction can be quickly, accurately and reliably obtained, and accurately and reliably. The magnitude of the maximum permissible residual unbalance at the position of each correction surface can be immediately determined in accordance with the axial position of the determined center of mass of the rotating body, and as a result, the mass distribution of the rotating body can be quickly and appropriately adjusted. This makes it possible to balance the rotating body (claim 1).

[Brief description of the drawings]

FIG. 1 is a conceptual side view of a balancing tester according to one embodiment of the present invention.

FIG. 2 is a side view of the rotator supported by the balancing tester according to the embodiment of FIG. 1;

FIG. 3 is a side view of a rotating body supported by a conventional balancing tester.

FIG. 4 is a side view of a rotating body different from FIG. 3 in a state of being supported by a conventional balancing tester.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Base or bed 2, 3 Vibration gantry 4a, 4b, 4c, 4d Strain gauge as load detecting means 5a, 5b Load meter as load detecting means 6, 7, 8 Rotating body A, B Correcting surface C Rotating body centroid plane P ₁ perpendicular to the street axis of rotation, P ₂ load R _1, the center of mass of the R ₂ bearing S rotator

Claims (1)

[Claims] 1. A balancing tester for performing a balancing test on a rotating body, said balancing testing machine comprising a plurality of rotatably supported rotatable members at positions spaced from each other in a direction of a rotation axis of said rotating body. A load detecting unit that detects a magnitude of a static load of the rotating body that is applied to the rotating body supporting unit for each of the rotating body supporting units while the rotating body is supported by the rotating body supporting unit; And a balance testing machine.