JPS6256452B2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention provides an eccentricity compensation method in unbalance measurement;
In particular, the present invention relates to a technique for compensating for eccentricity between the rotating shaft and a bearing supporting the rotating shaft when the rotating shaft as a test specimen has a bearing portion in the longitudinally intermediate portion thereof.

A rotating shaft body, especially a rotating shaft body such as an automobile propeller shaft, is tested by placing the rotating shaft body 1 in an unbalance tester 6 equipped with sleeve bearings 2 and 3 and rotating it, as shown in FIG. There are devices that measure unbalance, but when the unbalance of the rotating shaft body 1 is measured using such an unbalance tester 6, it is found that there is eccentricity between the sleeve bearings 2, 3 and the rotating shaft body 1. Since the rotating shaft body 1, which is the test object, is swung around, an unbalance due to the eccentricity may be detected even if there is no unbalance in the test object itself. That is, for example, in the part where the rotating shaft body 1 is supported by the sleeve bearing 2, an eccentricity a exists between the rotation center axis 7 of the rotor 4 fitted in the bearing part and the rotation center axis 8 of the rotating shaft body 1, and There is an eccentricity b between the rotation center axis 9 of the rotor 5 fitted in the bearing part of the sleeve bearing 3 and the rotation center axis 8 of the rotation shaft body 1.
If this exists, even if the unbalance of the rotating shaft body 1 itself is 0, an unbalance proportional to the eccentricities a and b will be detected. Such eccentricity a,
In order to detect and correct the unbalance caused by eccentricity a, a reversal test is conventionally performed in which the phase of the rotating shaft body 1 is shifted by 180 degrees, and the unbalance caused by eccentricity a is separated and canceled. There was a method in which the sleeve bearing 2 side was corrected with a', while the unbalance caused by eccentricity b was corrected with b' on the sleeve bearing 3 side. As a result, the influence of the eccentricities a and b is removed, and the unbalance of only the rotating shaft body 1 can be detected.

However, there is a structure in which the rotating shaft body 1 itself has a bearing portion at an intermediate position. Such a rotating shaft body 1
To carry out an unbalance test, the rotary shaft body 1 is supported by sleeve bearings 2 and 3 at both ends, and supported by a third bearing at the intermediate bearing part, rotated, and the unbalance measured. Bearing 2
The unbalance is corrected by the correction surface A corresponding to the sleeve bearing 3, the correction surface C corresponding to the sleeve bearing 3, and the correction surface B corresponding to the third bearing. However, in general, the surfaces A, B, and C where the unbalance is corrected and the surfaces where eccentricity occurs between the rotating shaft body 1 and the sleeve bearings 2 and 3 as described above (that is, the surface where the eccentricity occurs between the rotating shaft body 1 and the sleeve bearings 2 and 3) When performing a reversal test with a separate circuit set up on the corrected surface, the eccentricities a and b were also affecting corrected surface B, but the test did not occur on the third bearing part. Because the body is self-bearing, it could not be directly corrected by the above-mentioned inversion test.

The present invention has been made to solve the above-mentioned conventional problems, and its purpose is to detect the eccentricity between the rotating shaft and the sleeve bearing that supports it in unbalance measurement of the rotating shaft. It is an object of the present invention to provide an eccentricity compensation method that allows a considerable amount of correction to be removed also to the correction surface B.

In order to achieve this object, the present invention memorizes the rotation of the rotating shaft body and the measured values obtained through two reversal tests, and stores these measured values in order to compensate for the eccentricity at the correction surface B corresponding to the third bearing. Calculate the eccentricity compensation amount corresponding to each correction surface from the measured value,
The gist of the present invention is to add this eccentricity compensation amount to the unbalance measurement value and remove the amount corresponding to the eccentricity from the unbalance measurement value. By adopting such an electrical compensation method, even if there is eccentricity between the rotating shaft body and the sleeve bearing, it is possible to correct the unbalance by removing the amount equivalent to this eccentricity by calculation. The influence of eccentricity on the bearing section can be removed.

Hereinafter, one embodiment of the present invention will be described in detail with reference to the accompanying drawings.

FIGS. 2 and 3 are diagrams showing an embodiment of the present invention. Of these, FIG. 2 is a diagram showing a measuring mechanism in the unbalance tester employed in the present invention. This mechanism supports both ends of a rotating shaft body 1 having bearing parts 12, 13, and 14 at predetermined positions in the longitudinal direction by sleeve bearings 2 and 3;
The bearing portion 13 of the rotating shaft body 1 is supported by a bearing 28, and the sleeve bearings 2, 3 and the bearing 28 are each supported by elastic members 10, 17, 15, and each bearing 2, 3 is supported by an elastic member 10, 17, 15. , 28 are connected to pickups 11, 18, and 16, and these pickups 11, 18, and 16 detect vibrations of each part and measure unbalance. The rotor 5 of the sleeve bearing 3 has a universal joint 19 having joint parts 20 and 21.
A pulley 22 is connected to the universal joint 19, and a belt 23 is connected to the pulley 22.
The rotary shaft body 1 is operatively connected to the motor 25 through a pulley 24 which is connected to the motor 25 through a pulley 24 which is fixedly connected to an output shaft 26 of the motor 25, and receives the driving force of the motor 25 to rotate the rotary shaft body 1 at high speed. Further, a reference signal generator 27 is connected to the rotor 5, so that a phase change between the sleeve bearing 3 and the rotating shaft body 1 can be detected. It is electrically connected to a storage circuit not shown. After loading the rotating shaft body 1 into the unbalance testing machine 6, (A) First, the rotating shaft body 1 is rotated by the drive of the motor 25, and each pick-up 11, 1 at that time is rotated.
The measured values on each bearing surface based on the detected values of 6 and 18 are stored in a storage circuit.

(B) Next, leave one sleeve bearing (for example, sleeve bearing 3) as it is, reverse the connection by 180 degrees at the connection part between the other sleeve bearing 2 and the rotating shaft body 1, and then install it. Rotating shaft body 1
The measured values of each bearing surface at that time are stored in the memory circuit.

(C) Furthermore, leave the sleeve bearing 2 as it is, reverse the connection by 180 degrees at the connection part between the sleeve bearing 3 and the rotating shaft 1, and then install it, rotate the rotating shaft 1, and then The measured values of each bearing surface are stored in a storage circuit.

The amount of eccentricity compensation for each surface is calculated from the measured values obtained through the reversal operation, and this is stored in the storage circuit. When measuring the unbalance of the rotating shaft body 1, the eccentricity compensation amount is added to the unbalance amount on each surface detected by the circuit that measures this unbalance, and after being calculated, the eccentricity compensation amount is calculated. The unbalance of only the rotary shaft body 1 from which is removed is obtained.

In this way, each pick-up 11, 16, 18
A measuring circuit for detecting the amount of unbalance and compensating for eccentricity based on the signals from the sensor is shown in FIG. In this figure, pick-ups 11, 16, 18
are unbalance detection circuits 29, 30, and 3, respectively.
1, and these unbalance detection circuits 29, 30, 31 are connected such that the output signals therefrom are input to a correction surface separation and sensitivity circuit 32. Further, the reference signal generator 27 connected to the sleeve bearing 3 is connected to each unbalance detection circuit 29,
30 and 31, and sends a signal indicating the reference phase to these circuits. Unbalance detection circuit 29, 3
Each pickup 1 detected by 0,31
The unbalance amounts at the 1st, 16th, and 18th portions are input to the correction surface separation and sensitivity circuit 32, and are converted into the unbalance amounts at each correction surface A, B, and C on which unbalance correction is to be performed. Furthermore, the correction surface separation and sensitivity circuit 32 outputs an unbalance signal corresponding to each correction surface, and also the eccentricity compensation circuits 33, 34, 35 provided corresponding to each correction surface.
is input to. Each of these eccentricity compensation circuits 33,
A compensation amount storage circuit 36 is connected to 34 and 35, and display meters 37, 38 and 39 are also connected thereto. The compensation amount storage circuit 36 stores the magnitude and direction of the eccentricity compensation amount obtained by the reversal test. Therefore, when measuring the unbalance of the rotating shaft body 1, the eccentricity compensation amount is added to the unbalance amount on each surface detected by the correction surface separation and sensitivity circuit 32 in the eccentricity compensation circuits 33, 34, and 35. be done. As a result, the display meters 37, 38, and 39 display only the unbalance of the rotary shaft body 1 from which the amount corresponding to eccentricity has been removed. Therefore, this display meter 37, 38, 3
By correcting the unbalance in each of the correction planes A, B, and C according to the instruction value 9, it is possible to correct the unbalance caused only by the rotating shaft body 1.

In order to compensate for eccentricity in unbalance measurement using the method described above, it is necessary to always maintain the same phase relationship between the sleeve bearings 2 and 3 during the reversal test.

As explained above, according to the present invention, when measuring unbalance using an unbalance tester, a reversal test is performed to determine the amount of eccentricity compensation between the rotating shaft and the sleeve bearing that supports it. Calculate the amount of eccentricity compensation corresponding to each correction surface on the rotating shaft body based on the measured value obtained in each reversal test, add this amount of eccentricity compensation to the unbalance measurement value, and calculate from the unbalance measurement value. Since the amount corresponding to eccentricity is removed, it is possible to prevent the influence of eccentricity between the rotating shaft body and the sleeve bearing from affecting unbalance correction on each correction surface.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing a general configuration in which a rotating shaft body is supported by a sleeve bearing and unbalance measurement is performed. FIG. 2 is a schematic explanatory diagram showing a configuration for measuring unbalance of a rotating shaft body employing the eccentricity compensation method of the present invention. FIG. 3 is a block diagram showing an unbalance measurement circuit employing the eccentricity compensation method of the present invention. 1... Rotating shaft body, 2, 3... Sleeve bearing, 6
...Unbalance tester, 7, 8, 9... Rotation center axis, 11, 16, 18... Pickup, 27...
...Reference signal generator.

Claims (1)

[Scope of Claims] 1. A rotating shaft body having a bearing portion at an intermediate portion in the longitudinal direction is supported by sleeve bearings at both ends thereof, and the bearing portion at the intermediate portion is supported by a third bearing, and these bearings are supported by sleeve bearings at both ends thereof. In the method of correcting the amount of unbalance of the rotating shaft by connecting a pick-up to the rotary shaft and rotating the rotating shaft, the unbalance measured by each pick-up at that time is memorized, and one of the After installing the sleeve bearing by reversing the connection between the bearing and the rotating shaft body by 180 degrees, rotate the rotating shaft body, memorize the unbalance measurement value from each pick-up at that time, and then apply the unbalance measurement value to the other sleeve bearing. After installing the bearing and rotating shaft with the connection reversed by 180 degrees, rotate the rotating shaft, memorize the unbalance measurement values from each pick-up at that time, and use the measured values obtained in each of the above-mentioned reversal tests. By calculating the eccentricity compensation amount corresponding to each correction surface on the rotating shaft body and adding this eccentricity compensation amount to the unbalance measurement value, the eccentricity equivalent amount is removed from the unbalance measurement value of all correction surfaces. An eccentricity compensation method in unbalance measurement characterized by the following.