TW201914740A - Geometric precision error measuring device and measuring method for rotary table capable of obtaining the data through performing a combined calculation - Google Patents

Abstract

A geometric precision error measuring device for a rotary table is provided, which is configured to five-axis machining. The five-axis machining has an oscillating table pivotable along the A axis, a working table rotatable along the C axis, and a feeding platform movable along the X axis, the Y axis, and the Z-axis. The working table is provided with a standard sphere located on the A axis, and the feeding platform is provided with a three-direction displacement sensor connected to the standard sphere. A calculation unit calculates the theoretical trajectory of the standard sphere according to the relative distance between the standard sphere and the C axis and calculates the movement trajectory of the feeding platform to maintain the relative position of the three-direction displacement sensor with the standard sphere. With the above device, the standard sphere is set on a plurality of positions to be tested on the working table, and a plurality of measurement information is measured, and the geometric precision error can be obtained by performing the combined calculation.

Description

Rotary table geometric accuracy error measuring device and measuring method

The invention relates to an automatic processing machine, in particular to a device and a method for measuring the geometric accuracy error of a workbench of a processing machine.

In general, there are 43 geometric errors in the 5-axis machining machine, and the rotating table has 6 degrees of freedom error during the movement. The error value must be obtained through the measurement, and the correction value can be corrected or corrected to improve Precision.

The conventional technique performs error measurement by a rotation accuracy tester, which sets a standard sphere on a rotating shaft to perform continuous rotation of a fixed rotation speed, and obtains an error value by a mathematical method. However, due to the mechanical design relationship of the tilting rotary table, the standard ball cannot be mounted on the shaft without the mechanism of infinite rotation, so the tester cannot be used for measurement.

In view of this, how to improve the above problems is the primary problem to be solved by the present invention.

The main object of the present invention is to provide a rotating table geometric accuracy error measuring device and method, which can reduce the influence caused by the linear axis geometric error, and obtain several measurement information at different positions, and obtain a more accurate calculation through the combined calculation. Geometric accuracy error value.

In order to achieve the foregoing objective, the present invention provides a rotary table geometric accuracy error measuring device, which is provided with a five-axis machining unit, wherein the five-axis machining machine has an oscillating table with a virtual A-axis as a pivot center. a table disposed on the oscillating table and having a virtual C axis as a center of rotation and a feed platform movable along a three-dimensional axial system including an X-axis, a Y-axis, and a Z-axis; the measuring device includes There is: a standard ball, which is disposed on the table and can be driven by the rotation of the table, the center of the standard ball is located on the A axis; a three-direction displacement sensor is disposed in the Moving on the platform and being movable by the feeding platform, the three-direction displacement sensor is connected with the standard sphere; a calculation unit that calculates the standard sphere according to the relative distance between the standard sphere and the C axis A theoretical trajectory is calculated according to the theoretical trajectory, and the three-direction displacement sensor maintains its relative position with the standard sphere.

The invention further provides a measuring method using the foregoing measuring device, which comprises: A. Defining a plurality of locations to be tested along the X axis on the workbench; B. Setting the standard sphere to one of the positions to be tested, and the center of the standard sphere is located on the A axis; C. Calculating the theoretical trajectory of the standard sphere by the calculation unit, and calculating the movement trajectory of the feed platform according to the theoretical trajectory; D. Measuring the movement of the standard sphere by the three-direction displacement sensor, and obtaining a measurement information; Repeat steps B to D to measure the measurement information of the standard sphere at all positions to be tested; Combine all measurement information.

The above objects and advantages of the present invention will be readily understood from the following detailed description of the embodiments of the invention.

Please refer to FIG. 1 to FIG. 3 , which is a rotating table geometric accuracy error measuring device provided by the present invention, which is assembled with a five-axis processing machine 1 having an oscillating table 11 . a table 12 and a feed platform 13 , wherein the oscillating table 11 is pivotally mounted on a fixed frame 14 and can pivot at a virtual A axis; the table 12 is disposed on the oscillating table 11 and can be rotated by a virtual C axis as a center of rotation; and the feed platform 13 can be moved along a three-dimensional axial system including an X-axis, a Y-axis, and a Z-axis.

The above processing machine may cause errors due to part dimensional accuracy or assembly accuracy, including component errors and position errors. Component error means that the error value will change with the position. For example, when moving along the X axis, it will cause a movement error in the Y direction or the Z direction; the position error means that the rotation axis is not at its position. The error value does not change with the position. For example, the two axes that are perpendicular to each other are not perpendicular to each other to form an error. When one of the axes is rotated, the error does not change with the rotation.

The measuring device 2 of the present invention comprises a standard ball 21, a three-direction displacement sensor 22 and a calculation unit (not shown). The standard ball 21 is disposed on the table 12 and can be driven by the rotation of the table 12, wherein the standard ball 21 is supported by a support base 211, and the center of the standard ball 21 is located at the center. On the A axis. The three-direction displacement sensor 22 is disposed on the feeding platform 13 and can be moved by the feeding platform 13 , and the three-direction displacement sensor 22 is connected to the standard ball 21 . The calculation unit is configured to calculate a theoretical trajectory of the standard sphere 21 according to the relative distance between the standard sphere 21 and the C axis, and calculate a movement trajectory of the feed platform 13 according to the theoretical trajectory, thereby When the feed platform 13 moves along the movement trajectory, the three-direction displacement sensor 22 maintains its relative position with the standard sphere 21.

With the above device, the present invention further provides a measurement method as shown in FIG. 4, which includes: A. Defining a plurality of locations to be tested along the X axis on the workbench; B. Setting the standard sphere to one of the positions to be tested, and the center of the standard sphere is located on the A axis; C. Calculating the theoretical trajectory of the standard sphere by the calculation unit, and calculating the movement trajectory of the feed platform according to the theoretical trajectory; D. Measuring the movement of the standard sphere by the three-direction displacement sensor, and obtaining a measurement information; Repeat steps B to D to measure the measurement information of the standard sphere at all positions to be tested; Combine all measurement information.

In the above method, the standard ball 21 is disposed at a position where the center of the ball is located on the A axis, and the position error described above can be removed, and a more accurate measurement result is obtained in the subsequent D step, that is, only the component is obtained. error. For example, in the measurement of the geometric accuracy error of the table 12 (C axis), as shown in FIG. 5, the standard ball 21 is rotated by the table 12, and the three-direction displacement sensor is used. 22 measuring the difference between the actual position and the theoretical position of the standard ball 21, the measurement information of the error can be obtained, and after all the measurement information is obtained at all the positions to be tested, the work table can be obtained by combining the calculations. Geometric accuracy error of 12 (C axis).

On the other hand, in the measurement of the geometric accuracy error of the oscillating table 11 (A-axis), as shown in FIG. 6, the standard ball 21 is pivoted with the oscillating table 11, and the three-direction displacement sensing is performed. The device 22 measures the difference between the actual position and the theoretical position of the standard sphere 21, and can obtain the measurement information of the error, and after obtaining all the measurement information at all the positions to be tested, the combined calculation can obtain the swing. Geometric accuracy error of stage 11 (A axis).

However, the above description of the embodiments is merely illustrative of the invention and is not intended to limit the invention, and the replacement of equivalent elements is still within the scope of the invention.

In summary, it will be apparent to those skilled in the art that the present invention can achieve the foregoing objectives and is in accordance with the provisions of the Patent Law.

1‧‧‧5-axis processing machine

11‧‧‧ swinging table

12‧‧‧Workbench

13‧‧‧Feeding platform

14‧‧‧ Fixing frame

2‧‧‧Measurement device

21‧‧‧Standard ball

211‧‧‧ support

22‧‧‧Three-direction displacement sensor

1 is a schematic perspective view of the measuring device of the present invention; FIGS. 2 and 3 are schematic plan views of the measuring device of the present invention; FIG. 4 is a flow chart of the measuring method of the present invention; Schematic diagram of the use state of the axis geometric accuracy error; Fig. 6 is a schematic view showing the use state of the A-axis geometric accuracy error of the present invention.

Claims (2)

A rotary table geometric precision error measuring device is provided with a five-axis machining unit, wherein the five-axis machining machine has an oscillating table with a virtual A axis as a pivoting center, and one of the oscillating tables is disposed on the oscillating table a virtual C axis is a rotating center table and a feeding platform movable along a three-dimensional axial system including an X axis, a Y axis, and a Z axis; the measuring device comprises: a standard ball, which is provided On the workbench and can be driven by the rotation of the workbench, the center of the standard sphere is located on the A axis; a three-direction displacement sensor is disposed on the feed platform and can be fed by the The platform drives the movement, and the three-direction displacement sensor is connected to the standard sphere; a calculation unit that calculates a theoretical trajectory of the standard sphere according to the relative distance between the standard sphere and the C-axis, and according to the theory The trajectory calculates a movement trajectory of the one of the feed platforms such that the three-way displacement sensor maintains its relative position to the standard sphere. A measuring method using the measuring device according to claim 1, which comprises: A. Defining a plurality of locations to be tested along the X axis on the workbench; B. Positioning the standard sphere on one of the positions to be tested, and the center of the standard sphere is located on the A axis; C. Calculating the theoretical trajectory of the standard sphere by the calculating unit, and calculating the movement trajectory of the feeding platform according to the theoretical trajectory; D. Measuring the movement of the standard sphere by the three-direction displacement sensor, and obtaining a measurement information; Repeat steps B to D to measure the measurement of the standard sphere at all positions to be tested; Combine all measurement information.