JPH0676944B2 - Eccentricity correction method for balance testing machine and balance testing machine - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an eccentricity correction method and a balance tester for electrically correcting the eccentricity of a support adapter that supports an object to be tested that does not have a rotary spindle.

2. Description of the Related Art When measuring the imbalance of a device under test, in order to improve the measurement accuracy, it is necessary to correct the eccentricity present in a support adapter that supports the device under test. Therefore, after attaching the DUT to the support adapter and rotating it to perform the first balance test,
Rotate the mounting angle of the DUT to the support adapter by 180 degrees and perform the second balancing test. An eccentricity correction vector is calculated from the two eccentricity vectors indicating the imbalance obtained by the two balance tests, and an electrical method for correcting the eccentricity of the support adapter and the first balance test are performed. When performing the correction to make the unbalance to be 0, and to make the unbalance shown in the second balance test to be 0, make a half of the correction by attaching a weight to the DUT, and There is a mechanical method of compensating for the eccentricity of the support adapter by compensating for half with the support adapter.

Problems to be Solved by the Invention The position where the DUT comes into contact with the support adapter does not lie on the same circumference and is slightly deviated. If the mounting angle is different, the eccentricity of the support adapter will be different, and as described above,
When correcting the eccentricity of the support adapter by two equilibrium tests in which the mounting angles differ from each other by 180 degrees, the eccentricity that occurs when the DUT is mounted at an angle deviating from the mounting angle cannot be sufficiently corrected. become.

The present invention has been invented in order to solve the above problems, and a balance tester capable of accurately correcting the eccentricity of the support adapter even when the DUT is attached in any direction. It is an object of the present invention to provide an eccentricity correction method and a balance tester capable of accurately performing a balance test of a device under test.

Means for Solving the Problems In order to achieve the above object, the eccentricity correction method for a balance testing machine of the present invention conducts a balance test with three or more N mounting angles. The eccentricity of the support adapter is shown from the eccentricity of the support adapter and the unbalance of the DUT, and the eccentricity of the support adapter is calculated from the N eccentricity vectors obtained by the balance test and the mounting angles corresponding to these eccentricity vectors. Compute an averaged eccentricity correction vector that corrects the core. Next, this averaged eccentricity correction vector is converted into a correction electric signal, and this correction electric signal is converted into a displacement signal indicating the displacement of the center of rotation of the main spindle for measurement, which is mounted and rotated by the DUT. Add signals.

Further, the balance testing machine of the present invention separates the displacement signal from the pickup into two directions orthogonal to each other, and a synchronous rectification circuit for generating an eccentricity vector signal indicating an eccentricity vector, and A / D for digitizing the eccentricity vector signal. The eccentricity of the support adapter is corrected from the D conversion circuit and the N eccentricity vectors obtained by the N-type balance test and indicated by the digitized eccentricity vector signal and the mounting angle corresponding to the eccentricity vector. CPU that calculates the averaged eccentricity correction vector
And a vector generation circuit that generates a correction vector signal corresponding to the averaged eccentricity correction vector, and an addition circuit that adds the correction vector signal to the displacement signal.

Action Perform the measurement three or more times while changing the mounting angle of the DUT to the support adapter sequentially, and attach the eccentricity vector indicating the result of each measurement and the DUT corresponding to this eccentricity vector to the support adapter. Get the angle and. The CPU calculates one eccentricity correction vector from the two eccentricity vectors. Two or more eccentricity correction vectors are obtained from the three or more eccentricity vectors, and the CPU further calculates these eccentricity correction vectors to calculate one averaged eccentricity correction vector. Then, the vector generation circuit generates a correction vector signal corresponding to the averaged eccentricity correction vector and adds it to the displacement signal from the pickup.

Example One example of the present invention will be described below. FIG. 1 is a block diagram showing a balance testing machine of the present invention. In the figure, the measurement main shaft 43 to which the DUT 41 is attached via a support adapter 42 is rotated by a drive unit (not shown). Due to the eccentricity of the support adapter 42 and the DUT 41, the center of rotation of the measuring spindle 43 is displaced, and this displacement is converted into a displacement signal 31 by the pickup 11. The displacement signal 31 reaches the synchronous rectification circuit 13 through the adder circuit 12 and is output as two orthogonal X and Y separation signals 32. The two separated signals 32 are digitized by the A / D conversion circuit 14, and become a signal 33 indicating an eccentricity vector and guided to the CPU 15. A keyboard 18 for inputting necessary data, for example, a mounting angle of the equilibrium tester 41 with respect to the support adapter 42, is connected to the CPU 15. Further, the CPU 15 exchanges data with the storage unit 22, and the device under test 41
The measurement result is output to the display unit 16 that displays the unbalanced value of. The output from the CPU 15 is guided to a vector generation circuit 23 which is composed of a D / A conversion circuit 17 and a chopper circuit 20 whose output is connected to the input, and is averaged to show its details later. It becomes a correction vector signal corresponding to the eccentricity correction vector and is picked up by the adder circuit 12.
It has been added to the displacement signal 31 from 11. The signal from the reference phase detector 21 for detecting the rotational position of the measuring spindle 43 is 2
It is guided to the phase pulse generation circuit 19. Two-phase pulses corresponding to the rotational position of the measuring main shaft 43 and having phases different from each other by 90 degrees appear in the output, and are sent to the synchronous rectification circuit 13 and the chopper circuit 20.

In the following, for example, the support adapter 42 can be attached in four ways, and the eccentricity of the support adapter 42 is corrected when performing the balance test of the DUT 41 having the attachment angles different from each other by 90. The operation at that time will be described.

The DUT 41 is attached to the support adapter 42 at an attachment angle of 0 degree, and the measurement spindle 43 is rotated. The displacement signal 31 from the pickup 11 is separated by the synchronous rectification circuit 13 into two orthogonal separation signals 32, which are separated by A / D.
It is sent to the CPU 15 after being digitized by the conversion circuit 14. At this time, the first eccentricity vector in which the unbalance of the DUT 41 and the eccentricity of the support adapter 42 are combined is shown to the CPU 15 by the digitized separation signal 32 and further inputted from the keyboard 18. With the data of mounting angle 0 degree,
The first eccentricity vector is stored in the storage unit 22.

Next, the DUT 41 is attached by rotating it by 90 degrees with respect to the support adapter 42, and the data of the second eccentricity vector and its attachment angle of 90 degrees are stored in the same manner. By rotating the mounting angle by 90 degrees, four eccentricity vectors and mounting angle data corresponding to the eccentricity vectors are stored in the storage unit 22.

FIG. 2 is an explanatory diagram showing an eccentricity vector. Vector S
Indicates the first eccentricity vector S1 and the second eccentricity vector S2 by measurement, the vector M indicates the unbalance of the DUT 41, and the vector U indicates the eccentricity of the support adapter 42. The angle θ of the intersection of the vector M1 and the vector M2 is equal to the rotation angle of the mounting angle of the device under test 41 and is 90 degrees. The vector U indicating the eccentricity of the support adapter 42 is slightly different between U1 and U2 because the eccentricity of the support adapter 42 shifts depending on the mounting angle of the DUT 41. Compared to the difference between the vectors S1 and S2 and the difference between the vectors M1 and M2, the difference between the vectors U1 and U2 is relatively small.
Calculation is performed assuming that U2 is the same vector.

FIG. 3 is an explanatory view showing the eccentricity of the support adapter 42 with the same vector. Since the vector M2 is a vector obtained by rotating the vector M1 by θ degrees, it is represented by M2 = M1e ^jθ , and S1 = A1 + M1 S2 = A1 + M1e ^jθ . And the vector showing the eccentricity of the support adapter 42 is Therefore, the vector A1 can be obtained from the vectors S2 and S1 and the mounting angle θ. CPU15
The above calculation is performed according to to store the vector A1 in the storage unit 22. Similarly, two vectors indicating the eccentricity of the support adapter 42 are obtained between the first eccentricity vector s1 and the third eccentricity vector and the fourth eccentricity vector.

FIG. 4 is an explanatory diagram for obtaining the eccentricity correction vector. By the above method, three vectors A indicating the eccentricity of the support adapter 42 are obtained, and these three vectors are different because the eccentricity of the support adapter 42 depends on the attachment angle of the DUT 41 to the support adapter 42. Is different. That is, in the above calculation, using the vector U1 as a reference, U1 and U2, U1 and U3, U1 and U4 were regarded as the same vector, and the vectors A1, A2, and A3 were calculated, but they were calculated by each calculation. Since the errors existing between the vectors U1, U2, U3, and U4 are reflected in the vectors A1, A2, and A3, the vector obtained by averaging the vectors A1, A2, and A3 is the vector U1, U2, and U3. , U4 is approximated with the averaged vector. In FIG. 4, a vector V is a vector showing an averaged eccentricity of the support adapter 42 obtained by averaging the vectors A1, A2, A3, and an eccentricity averaged by rotating the vector V by 180 degrees. It becomes a correction vector. The above calculation is performed by the CPU 15.

Return to FIG. The correction vector signal corresponding to the averaged eccentricity correction vector obtained by the above method is
Generated by the A conversion circuit 17 and the chopper circuit 20,
By adding it to the displacement signal 31 from the pickup 11, the eccentricity of the support adapter 42 is corrected. The display unit 16 is
The corrected value is displayed.

Note that the present invention is not limited to the above embodiment, and in the vector calculation, the vector A indicating the eccentricity of the support adapter 42 is calculated from the relationship with the first eccentricity vector s1. It is possible to calculate the vector A indicating the eccentricity of the support adapter 42 from the relationship with the arbitrary eccentricity vector of 4.

The mounting angle of the DUT 41 to the support adapter 42 is
If there are three or more types, it can be applied to the case of the DUT that can be attached at any attachment angle.

EFFECTS OF THE INVENTION The dynamic balance tester of the present invention has an eccentricity vector obtained by three or more balancing tests with different attachment angles for attaching a DUT to a support adapter, and an attachment angle corresponding to the eccentricity vector. From, calculate the average value of the eccentricity of the support adapter,
Since the correction is performed based on the value, it is possible to accurately correct the eccentricity of the support adapter even when the DUT is attached in any direction.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of the balance tester of the present invention, FIG. 2 is an explanatory view showing an eccentricity vector, and FIG. 3 shows the eccentricity of the support adapter 42 with the same vector. Illustration,
FIG. 4 is an explanatory diagram for obtaining the eccentricity correction vector. 11 …… Pickup, 12 …… Adding circuit, 13 …… Synchronous rectification circuit, 14 …… A / D conversion circuit, 15 …… CPU, 16 …… Display section,
23 …… Vector generator circuit, 41 …… DUT, 42 …… Support adapter, 43 …… Measuring spindle.

Claims (2)

[Claims] 1. An eccentricity correction method for correcting eccentricity of a support adapter for supporting a device under test which has three or more N mounting angles and does not have a main spindle of rotation. Shows the eccentricity caused by the step of performing the balance test and the eccentricity of the support adapter and the unbalance of the DUT, and corresponds to N eccentricity vectors obtained by the balance test and these eccentricity vectors. Calculating an averaged eccentricity correction vector for correcting the eccentricity of the support adapter from the mounting angle, and converting the averaged eccentricity correction vector to a correction vector signal, And a step of adding the correction vector signal to a displacement signal indicating a displacement of a rotation center of a measuring main shaft to which a DUT is attached via the support adapter and rotating. Eccentricity correction method of balancing tester characterized and. 2. A balance testing machine for performing a balance test of an object under test having N or more mounting angles with respect to a support adapter and no rotating spindle, in two directions orthogonal to displacement signals from a pickup. A synchronous rectification circuit that separates and generates an eccentricity vector signal indicating an eccentricity vector, an A / D conversion circuit that digitizes the eccentricity vector signal, and the digitization obtained by the N-type balance test. A CPU that calculates an averaged eccentricity correction vector that corrects the eccentricity of the support adapter from the N eccentricity vectors indicated by the eccentricity vector signals and the mounting angles corresponding to these eccentricity vectors. A vector generating circuit for generating a correction vector signal corresponding to the averaged eccentricity correction vector, and an addition for adding the correction vector signal to the displacement signal Balancing machine, characterized in that a road.