TW523579B - Method for evaluating measurement error in coordinate measuring machine and gauge for coordinate measuring machine - Google Patents

Abstract

A gauge for a coordinate measuring machine has a plurality of balls whose centers are located on at least one line inclined with respect to a reference axis in a virtual reference plane. The gauge is set on a measuring table of the coordinate measuring machine. Orthogonal coordinate system having a coordinate axis identical to the reference axis is set in the virtual reference plane. The coordinates of the center of each ball are measured by the coordinate measuring machine. Thereafter, the gauge is turned and inverted by 180 degrees about the reference axis and is set again on the measuring table. The orthogonal coordinate system, having a coordinate axis identical to the reference axis, is set in the virtual reference plane. The coordinates of the center of each ball are measured in the same way as above. Thus, measurement errors of the straightness of the machine axes of the coordinate measuring machine and the orthogonality between the machine axes can be easily and precisely evaluated.

Description

523579 Case No. 90101765 Amended 5. Description of the invention (1) Background of the invention The method of the present invention relates to a method for measuring and determining the variation of the inherent error of a coordinate measuring instrument for measurement, such as the size of a mechanical part, etc. Coordinate measuring instrument gauge, which is used to measure the error of the coordinate measuring instrument. The description of the know-how is that the well-known coordinate measuring probe heads and devices can be mechanical, and the orthogonal direction shifting case reveals the type (guide ra) extending horizontally, the second horizontal portion of the direction to be installed on it. ), The contact is set in (3-di mens according to, for example, a movable probe that can move in three orthogonal directions, in order to measure the size of the object, the movable probe is placed on the measuring table to be measured Object contact. For example, the object part, such as the cylinder of an engine or the box of a transmission gearbox. In such a coordinate measuring instrument, the probe can move in three directions. For example, the publication number is Η 0 2-3 0 A coordinate measuring instrument for Japanese special review 6 1 0 1 in which the first gantry (movab 1 e member) moves linearly along a horizontal guide i 1), and the horizontal guide is on the opposite side of the measuring table The measuring object is fixed on the measuring table. The first moving member has a second moving member to move in a direction perpendicular to the moving direction of the first moving member. The moving part has a vertical movement axis (a spindle has a probe at the front end, and a ball is fixed on the probe. When the ball is measured on the object to be measured on the ball measuring table, the probe moves in the direction of three-dimensional i ο na 1) to measure the object Size of each part. If the ball of the probe is worn,

Page 4 523579 Case No. 90101765 Amendment V. Description of the Invention (2) It is no longer possible to set the measurement interval to correct the deviation of the guide due to the probe coordinate measurement movement, or the angle of the guide detection angle caused by the existing technical tester Acquired. Therefore, in recent years, the working efficiency of the measuring instrument is broken in the tilt of the needle ball instrument or the misalignment of the needle during the operation. On the other hand, it is eliminated from the calibration in the continuous invention method. The coordinates of the error book with the coordinates are used for orthogonal measurement of the coordinates. The invented measuring instrument measures on the axis according to the standard measurement. To prevent this, the reference gauge is measured on the measuring table to measure the error caused by the wear of each part of the reference gauge. Measurement errors include errors caused by bending movements of the probe head caused by guide members, such as probe head movement and twisting. It is time-consuming and labor-intensive to measure the straightness of the guides of the reference meters or the orthogonal calibration of the guides that are set on the measuring hall in different directions. On the other hand, coordinate measurement has been improved in companies or factories to determine the size of accurate and complex machined workpieces. From an economic point of view or considering practical applications, trend gauges do not have to periodically check their performance. The purpose is to provide a method for measuring the measurement error, in which the straightness and the orthogonality of the instrument axis can be conveniently and accurately completed. Related to the prior art instrument axis, another purpose is to provide a method for measuring measurement error. Meter. The error measurement of the base station of the present invention should be determined relative to the measurement error measurement method of the target measuring instrument, in which the probe head moves on three different phasor objects.

Page 523579 Amendment No. 901Q1765 V. Description of the invention (3) According to a phenomenon of the present invention, a method for measuring a measurement error of a coordinate measuring instrument is provided, in which the probe head is aligned along three mutually orthogonal instrument axes with respect to Measuring the movement of an object comprises: a first step, setting a measuring device for the measuring device on a measuring table of the coordinate measuring device, the measuring device having a plurality of balls, the center of the ball being at least one reference axis relative to the measuring device; The inclined straight lines are lined up. The reference axis is in a virtual reference plane and extends along the virtual reference plane, so that the reference axis is parallel to one of the three instrument axes of the coordinate measuring instrument and the virtual reference plane is Any two axes of the lower two instrument axes are parallel; in the second step, an orthogonal coordinate system is set, in which one of the coordinate axes is in the same direction as the reference axis in the virtual reference plane, so that the center of each ball is measured with respect to the two instrument axes by a coordinate measuring instrument The third step is to rotate the coordinate measuring instrument gauge by 180 degrees around the reference axis, and set the measurement on the measuring table of the coordinate measuring instrument again. ; And a fourth step of setting the orthogonal coordinates, wherein like reference axes in one coordinate axis with the virtual reference plane direction, such that each ball through the center coordinate measuring instrument measuring instrument with respect to two coordinate axes. According to the i-th ball center coordinate Y i perpendicular to the direction of the gauge reference axis of the coordinate measuring instrument obtained in the second step and the first The coordinates of the i-ball centers Y'i are determined by calculating the difference between the maximum and minimum values (Yab 1'2) / 2 to determine the straightness of the instrument axis in the direction of the reference axis. Moreover, in one embodiment, the coordinates of the center of the ball in the direction of the reference axis of the meter and in the direction perpendicular to the dacao axis obtained in the second step

Page 6 523579 _Case No. 90101765_ Year Month Amendment __ V. Description of the Invention (4) A regression line is obtained, from which the angle 0 between the regression line and the reference axis is calculated; thereafter obtained from the fourth step Obtain a regression line for the coordinates of the center of the ball in the direction of the reference axis of the gauge and in a direction perpendicular to the reference axis, and calculate the angle 0 'between the regression line and the reference axis, using (&9; 9-0') / 2 Measure the orthogonality of the two instrument axes parallel to the virtual reference plane. According to another phenomenon of the present invention, there is provided a coordinate measuring instrument gauge, comprising: a plurality of balls, a probe head of the coordinate measuring instrument is in contact with the ball; and a bracket supporting the ball, the balls are arranged along a line The line is inclined to a reference axis located in a virtual reference plane and extending along the virtual reference plane, and the bracket can be connected to a coordinate measuring instrument so that the virtual reference plane is parallel to two selectable instrument axes of the coordinate measuring instrument, Make the reference axis parallel to one of the two instrument axes. Preferably, the bracket is made of a trapezoidal block so that the balls are arranged and installed along each oblique line parallel to the non-parallel slope of the trapezoidal block. Preferably, the bracket is made of a block having a trapezoidal through-hole so that the balls are arranged and mounted along each line parallel to the relatively non-parallel slope of the through-hole. Detailed description of the present invention The present invention is suitable for measuring the measurement error of a coordinate measuring instrument, so that when the probe head is brought into contact with an object, each of the objects to be measured provided on the measuring table is measured by moving the probe head in the direction of three orthogonal axes. Partial dimensions. The error measurement of the coordinate measuring instrument includes the measurement of the relative pure value of the measured value obtained by measuring the distance between two separated points, the measurement of the straight line measurement value by moving the probe along the axis of the instrument, and the orthogonality of the two coordinate axes.

523579 _ Case No. 9Q1Q1765_ Year, month and month ___ V. Description of the invention (5) Determination. For the above error measurement, a coordinate measuring machine is used, which has a plurality of balls, the center of which is located along and along an oblique line extending in an inclined direction with respect to the reference axis in the virtual reference plane.

During the error measurement of the coordinate measuring instrument, the ball is in contact with the probe head. The surface of the ball is ground to obtain a high-precision spherical surface having a predetermined diameter, and each ball is made of a hard material having a low thermal coefficient, such as a Taurman material. The ball is fixed on a stand, which is mounted by a mounting bracket or fixture-on the measuring table of a coordinate measuring instrument. The bracket can be made of a highly rigid material with a low thermal coefficient, such as granite or non-shrinkable steel. In coordinate measuring instruments, the bracket can be made of a substantially planar trapezoidal block. The ball is fixed to one or two oblique or non-parallel surfaces of the block (bracket) so that the straight line or line connecting the center of the ball extends parallel to the oblique surface. Preferably, the line perpendicular to the virtual reference plane including the straight line extends in the thickness direction of the trapezoidal block, and the reference axis is perpendicular to the parallel side (bottom or top side) of the trapezoidal block.

If the bracket is made of an isosceles trapezoid, the ball is set on the two non-parallel side surfaces (slopes) of the isosceles trapezoid. It is better to include the two straight lines connecting the center of the ball in the virtual reference plane and relative to the virtual reference plane. The reference axes in the plane are arranged symmetrically. Alternatively, the bracket can be made into a basic flat block with a trapezoidal through-hole, in which the balls are arranged in a straight line and fixed to one or two relatively oblique or non-parallel sides of the trapezoidal through-hole, so that the line connecting the center of the ball with the corresponding bevel Extend in parallel.

Page 8 523579 Case No. 90101765 Amendment V. Description of the invention (6) In the latter choice of reference surface shape, this trapezoidal contact ball is included in the calibration of the root measuring instrument and the virtual parameters are set by orthogonal coordinates. Each bevel can be arranged on the points ball so that if the gauge base is orthogonal, it should be included outside the reference axis, such as the two virtual parameters of 孑 L. According to the error, the test surface of the bracket is perpendicular to the reference. According to the definition of DEK defined on the trapezoidal surface, the angle θ and the standard and positive coordinates are selected. The thickness of the bracket is perpendicular to the non-parallel straight line of the through hole. Make reference, measure at least two oblique virtual parameters. Each volleyball is measured. The coordinate coordinate axis is an isosceles trapezoidal side that extends the trapezoidal through-hole through a straight line with the best sag direction. The oblique surface is enclosed by a virtual reference axis. The shape of the reference coordinate measurement measurement and a row extended at the intersection measurement virtual parameters are used when the coordinate device is set on the base so that the reference axis and the two instrument axes are parallel to the axis. Line, the parallel side type, and the shell 1J is placed at the center. Gauge measurement instrument extension. Virtual horizontal axis (Each test surface of the device, the virtual support is a block surface. The ball is arranged on the isosceles and on the inclined surface with two straight lines relative to the device measurement coordinate measuring table, the axis of which extends parallel to the surface and It can be used as the three separation points on the center of the ball of the meter (space test surface. If the meter is made of trapezoidal blocks, then on the surface (non-parallel plane), measure the The center position defines the virtual reference coordinate set on the virtual reference plane. For the device coordinate system, you can make the gauges one by one (which can be used as the reference of the instrument coordinates), which is consistent with the instrument axis of the coordinate measuring instrument. Separate points to determine each

Page 9 523579 Case No. 90101765 Amendment V. Invention Description The center of the ball completes the measurement, such as measuring two points five times, and when determining the circle can be measured in a volley, this makes the measurement set on the reference axis. The measured change of the target ball is measured based on the comparison of the center of the ball, and the measured value of the reference axis spin can be set (Yi — Y, shown when the (7) position is set. When the ball's sphericity is determined according to the predetermined pure diameter value of the ball In order to measure the center of each ball, the position of a point is measured using a coordinate measuring probe, and the five points include four pole points on the equator of each ball, which are compared with the ball's predetermined purity. The diameter value compares the sphericity of the ball. The measurement of the center position of the ball is completed in such a way that the first ball to the last ball are successively measured. When the last ball is completed, the last ball to the first ball are sequentially reversed. Measure. Work is stable. When the gauge coordinates measure the center position of all balls, the gauge revolves and changes 180 degrees, and then the gauge is measured at the measuring table of the coordinate measuring instrument to determine the gauge base. . Therefore, for the 180 position, measure the center position of the gauge base in the same way as above. 'Based on the measurement of the center position of the ball obtained in this way', measure the distance between the nose specific and the center of the remaining ball, and The error is determined from the predetermined pure value. When the coordinate measuring instrument is placed with its front side facing up, and when it is placed on the coordinate measuring instrument by rotating 180 degrees, the error measurement is obtained by averaging the obtained values. The straightness of the instrument axis extending in the direction of the reference axis is taken as the deviation between the maximum value and the minimum value of i) / 2, where the Y i coordinate measuring instrument is measured with its front side facing up.

Page 10 523579 Amendment No. 90101765 V. Description of the invention (8) The center coordinate of the i-th ball in the direction perpendicular to the reference axis, Y'i means when the coordinate measuring instrument rotates around the reference axis by 180 degrees and sets The center coordinate of the i-th sphere in the direction perpendicular to the reference axis when obtained on the measuring table of a coordinate measuring instrument. When the front side of the coordinate measuring instrument is set up, the regression line is obtained by the least square method according to the coordinates X i of the i-th ball center in the direction of the reference axis and Y ii in the direction perpendicular to the reference axis. From this, the angle 0 between the regression line and the reference axis is calculated. When the coordinate measuring instrument is rotated 180 degrees around the reference axis and set on the measuring table, according to the coordinates X i of the i-th center of the ball in the direction of the reference axis and Y 'i in the direction perpendicular to the reference axis Coordinates, the regression line is obtained using the least square method, and the angle 0 'between the regression line and the reference axis is calculated from this. In this way, the orthogonality of the two instrument axes parallel to the virtual reference plane can be determined based on the value of (Θ _ 0 ′) / 2. In this way, the flatness of any instrument axis and the orthogonality between the two instrument axes can be determined by changing the setting angle of the coordinate measuring instrument about the coordinate measuring instrument measuring table, so that the reference axis and an instrument axis of the coordinate measuring instrument Parallel and make the virtual reference plane parallel to the two remaining instrument axes. Referring to the coordinate measuring machine gauge shown in FIG. 1, according to the present invention, the measuring machine is provided on the coordinate measuring machine to determine the error. It can be seen from FIG. 1 that the coordinate measuring instrument gauge 1 is mounted on a fixture plate 4 using a fixture (a mounting fixture) 5, and the fixture plate 4 is arranged on the measuring table 3 of the coordinate measuring instrument 2. The coordinate measuring instrument 2 includes a gantry-type movable frame 6, which is made on the opposite side of the measuring table 3 so as to slide in the X direction; the top 7, through

Page 523579

2 The movable frame 6 supports the top 7 to slide $ in the γ direction perpendicular to the χ direction; and the ascending / descending axis 8, which is composed of the neck part? The support is moved in the Z direction which is upward and opposite "] ^ "Tarabetsu straight to the Υ direction, so that it can move and place the probe 9 fixed to the lower end of the lifting shaft 8 in the direction of 1 :: 2 or mutually orthogonal ^ Text & You can move the frame 6, the top 7 and the lift well also Q > axis direction. It has an instrument coordinate system with axes X, ¥ and 2 in the coordinate measuring instrument 2. The coordinate system is used as the instrument coordinate As shown in Fig. 2, the probe 9 includes a connection 9A. The support shaft 9A has a support shaft fixed to the lower end of the ascending / descending shaft 8.

With measuring ball 9 β. 、 / 、、 Fixed support shafts 9 C, each support shaft 9 C, four support shafts 9 C are radially extended in four directions, so that the two shafts 9C extend parallel to the χ axis, and the plane is inclined at 90 degrees The inner stern wheel, while the fifth fulcrum 9 extends parallel to the water. Each measuring ball 9B is made of Shi Geng's anti-corrosion material in the straight direction, that is, in the 2 axis direction or ceramic, etc. Xingyou Chu— + > Precision-finished spherical surface. In the & quasi-measurement work, 'the probe 9 human measuring ball 9B and the measuring table placed on the coordinate measuring instrument 2] and the L support shaft, the workpiece of the moving unit & _. At first glance, the measurement table is as follows: ": Surface contact. The displacement of the measuring probe 9 is to check the coordinates of the instrument. This displacement is to move the measuring ball 9B from the touch position. The position moves toward the surface where the ball contacts the finished surface of the workpiece. Selection of connection direction: According to the position of the finished surface to be measured or the measuring ball 9 B touching the finished surface of the workpiece. &Quot; Check the accuracy of the coordinate measuring instrument 2 and calibrate it,

523579 Amendment No. 90101765 V. Description of the Invention (ί) The coordinate measuring instrument 1 shown in Fig. 1 is used instead of the workpiece to measure its measurement error. The coordinate measuring instrument 1 in the illustrated embodiment has a stand 10 made of a block of uniform thickness in the form of an isosceles trapezoid in the plan view, and a plurality of balls 1 1 which follow the trapezoidal block 1 Each of the opposite non-parallel or beveled edges of 0 are arranged and separated from each other at equal intervals, as shown in Figures 1, 3, 5, and 7. In the illustrated embodiment, the bracket 10 may be made of granite because these materials have a low coefficient of thermal expansion and are less affected by temperature changes. Each surface of the support 10 is finished to obtain a highly accurate ground surface. The bracket 10 has four through holes 10A extending in the thickness direction, that is, between its main surfaces. The through hole 10 A helps reduce weight and facilitates manipulation of the stand. The through hole 1 0 A and the side 10 B are suitable for mounting the bracket 10 on a mounting fixture (tool) 5. The side 10 B is consistent with the lower bottom surface of the trapezoidal bracket, which will be described below. Each ball 11 is made of highly-accurate precision-finished ceramics and has a spherical surface of a predetermined diameter and height. Five balls 11 are arranged on each oblique side of the stand along a straight line so that the centers of the balls 11 are equally spaced. It should be noted that, as shown in FIG. 6 in particular, a tapered groove consistent with the ball 1 1 is provided on each inclined surface of the bracket 10, and the ball 11 is preferably bonded to the periphery of the corresponding groove by an adhesive. .

Fig. 3 shows a coordinate measuring machine gauge 1, which is connected to a fixture plate 4 through a mounting clamp (tool) 5. The gauge 1 is firmly connected to the mounting fixture 5 so that the bracket 1 0 side 1 0 B which is consistent with the bottom surface of the trapezoidal block abuts on the upright contact plate 5 A provided at the end of the mounting fixture 5 and is adjacent to the side 1 0 B

Page 13 523579 ------ Case No. 9Q101765 _Revision · V. Description of the invention (U) The inner surface of a pair of through holes 1 0 A is pushed by the corresponding clip 12 and thus pushed Side 1 〇 B, 5 A against the abutment plate. As shown in FIG. 4, the mounting jig 5 includes a base plate 5B, an end of the contact plate 5A is fixed on the base plate 5B, an extension plate 5C is fixed on the base plate 5B, and an end portion with the contact plate 5 A of the base plate 5β The opposite end protrudes. Each clip 12 has a clip lever 12A which extends toward the abutment plate 5 and is movable in its axial direction. When the corresponding operation ring 1 2 B provided at the base end of the clamp lever is manually rotated by an associated screw mechanism (not shown), the clamp lever 1 2 A is axially moved (extended and retracted).

Two support pins 13 are not disposed on the base plate 5B near the abutting plate 5A, and one support pin is provided on the extension plate 5C. The supporting pin 13 is abutted against the bracket 10 of the coordinate measuring machine 1 so as to fix the bracket 10. The pin 13 is connected to the lower main surface of the bracket 10 to create a gap between the bracket 10 and the substrate 5B. In the illustrated embodiment, a large number of mounting holes are formed in the base plate 5 B, the extension plate 5 C, and the abutting plate 5 A. The clip mounting block 5D and the support pin 13 are fixed to the base plates 5B and 5C through a selected hole h. This makes it possible to selectively determine the position of the mounting hole h according to the pitch of the mounting hole h. It should be understood that the mounting hole h can also be used as a bolt insertion hole of a support bolt (not shown) to fix the mounting jig 5 to the history board 4.

The process of measuring the measurement error of the coordinate measuring instrument 2 using the meter 1 will be described below. Fig. 5 shows a plan view of the meter 1 when the meter 1 is set on the coordinate measuring device 2 as shown in Fig. 1. Set the coordinate measuring instrument gauge 1 so that the longitudinal center axis of the bracket i 〇 and the reference axis N extending substantially parallel to the instrument axis χ are precisely weighted 523579 Case No. 90101765 V. Description of the invention (12) 0

As shown in FIG. 5, the coordinate measuring instrument in the display example measures 10 balls U all about the reference sleeve N relative to the non-flat surface along the bracket 10; called the queuing so that the center of the ball on one side is equal. door

u 讲 々 古 # ^ ^ u Find a gap between them and line up on the straight line LI L2. -"The spacing is spaced apart and in a straight line. For the sake of clarity, it is assumed that the balls along the line L 1 丨 丨 The balls 1 1 along the line L 2 are the balls S 6 to S 1 0. By the sample, the head" '', > Discontinuance ^ n pressure measurement 1 instrument 2 starts the measurement work from the measurement position S1 at the center of the measurement ball S1. In this work, the measurement balls 9Bh9B5 on the probe 9 contact the ball si at five points one after the other The five points include four points on the equator of the ball S1. These points are the points p1, P2,? 3, and a point not shown in the diameter direction opposite to P2, and the point P5 at the pole ^. For example, the contact points P1, P5, ρ3 and the radially opposite contact point ρ2 are connected to each other, and each of them is in contact with the measuring ball 9 Β1, and then the contact point ρ2 is in contact with the measuring ball 9B5, as shown in Fig. 6 Then, the center position of the ball S1 can be determined geometrically based on the position of the contact point. It should be noted that the five balls 9 B shown in FIG. 6 are all in contact with the ball S 1. However, in reality, once There is only one ball 9B touching the ball si. It should be noted that "equat0r" refers to the large circle of the ball S1 '$ The large circle includes the ball S1 The diameter is in a vertical plane, which is perpendicular to the plane of the plane of FIG. 5 and is parallel to the reference axis N. The pole refers to a point on the ball S1 away from the associated side of the bracket. The distance from the vertical plane is the largest. Also 'measure the center position of the ball S5 on the line L 1 and the ball on the line L2

Page 15 523579 Case No. 90101765 Month Amendment V. Description of the invention (13) Center position of S 6 and S 1 0. As a result, a virtual reference plane including the centers of the four balls S1, S5, S6, and S10 can be determined. Therefore, the coordinate system related to the coordinate measuring instrument 1 is set as the coordinate system of the gauge, where the origin is determined by the intersection point between the axis "Aπ and the reference axis N, where the axis" Aπ represents the connecting balls S 1 and S 1 0 center line. The point of intersection is at the midpoint of the axis " A ". The gauge coordinate system corresponds to an orthogonal coordinate system having two orthogonal axes X and Y which are identical to the reference axis N and the axis "A" in the virtual reference plane, respectively. The coordinate system of the scale corresponds to the coordinate system of the instrument provided in the direction of the instrument axis of the coordinate measuring instrument 2 one by one. Therefore, the coordinates of the center of each ball can be found in the gage coordinate system. After the coordinates are set at the setting position of the coordinate measuring instrument, the center positions of the balls S1 to S 1 0 are measured one after the other, and then the ball S 1 0 to S 1 are measured sequentially in the reverse order, that is, from S 1 0 to S1. Central location. That is, four measurements are performed in the order of S 1-S 1 0, S1 0-S 1, S1-S1 0, and S1 0-S 1. In other words, the center position of each ball was measured twice during the movement from S 1 to S 10 and the return from S 1 0 to S 1 for a total of four times. After that, the coordinate measuring instrument is rotated (turned over) 180 degrees around the reference axis N and set on the mounting fixture 5 again. The virtual reference plane and axis "A" are determined in the same process as described above, and the new coordinate system is set on the coordinate measuring instrument 1. Therefore, the turning position of the measuring instrument 1 is the same as that of the measuring instrument 1 Measure the center positions of the balls S 1 to S 1 0 in the same way, and measure four times in total. After that, complete four forward measurements on each side of the meter 1

§

Page 16 523579 Case No. 90101765 Amendment V. Description of the invention (14) The measurement work for the two digits and four return measurements of the meter 1. Set a total of eight measurements per ball. In the measurement error measurement of the coordinate measuring instrument 2, the diameter measurement of the balls S 1 to S 1 0 and the pure values of the ball diameters of the balls S 1 to S 1 0 obtained by the measurement work are used. First, the measurement error of the ball stability measurement is completed. . Thereafter, as shown in FIG. 7, the X-axis direction (that is, the reference axis N direction) and the Y-axis between the center of the ball S 1 and the center of each ball S k are respectively calculated according to the measurement values of the front side of the meter 1 facing upward. The inner center distances △ X k-1 and △ Y k-1 in the direction (ie, the axis " A " direction) are compared with the pure value of the inner center distance to determine the error, where the term "kπ" represents from 2 to A number of 10, which is the value assigned to the ball for calculating the center-to-center distance from the center of the ball S1. As used herein, pure values are predetermined and known to be accurate. Thereafter, similarly, based on the measurement values of the meter 1 being rotated 180 degrees with its rear side facing upward, the inner distances between the center of the ball S 1 and the center of each ball Sk in the A-axis direction and the N-axis direction are calculated respectively. The center distances Δ X 'k-1 and Δ Y' k-1 are compared with the pure values of the inner center distances to determine the error. Here, the average value of the measured values obtained when the meter 1 is set with the front side facing upward and the meter 1 is turned with the back side facing upward is used to measure the error, thereby improving the measurement accuracy. In the coordinate measuring instrument gage of the illustrated embodiment, in order to complete the proportional calibration of the coordinate measuring instrument 2, it is possible to change the inclination angle of the inclined surface of the bracket 10 in a trapezoidal block with respect to the reference axis N from a small value to a large value. The values change the inner center distances Δ X ′ k-1 and Δ Y ′ k-1 in the A-axis direction and the N-axis direction between the ball S 1 and each ball Sk, respectively.

Page 17 523579 Case No. 90101765 Month Revision V. Description of the invention (15) Thereafter, the measurement of the straightness of the instrument axis of the coordinate measuring instrument 2 is realized. First set from when the coordinate measuring instrument gauge 1? The coordinate Y i of the ball S i when the front side is up and the coordinate Y 'i of the ball S i when the meter is turned upside down are calculated as 5i = (Yi — Y'i) / 2, where Si represents the first i balls. The labels n i " and n kπ are both free labels for the ball. t FIG. 8 shows the calculation results of (51 to 55) drawn in a diagram of five balls S1 to S5 provided on one side of the coordinate measuring machine gauge 1. The difference D between the maximum value and the minimum value is determined at The instrument vehicle in the X-axis direction is flatness. In Figure 8, the maximum value is given by 5 2 two (Y2 — Y '2) / 2, and the minimum value is given by 5 4 = (Y4 — Y' 4) / 2 Perform similar calculations for balls S 6 to S 1 0 to obtain the difference D between the maximum and minimum values of 5 i (i = 6 — 1 0). The average of the difference D is used to determine the flatness To improve the measurement accuracy. After that, the orthogonality measurement between the two axes of the coordinate measuring instrument 2 is completed. Referring to FIG. 9 first, when the front side of the measuring instrument 1 is set to face up, pass the minimum plane according to the center coordinates of the balls S1 to S 5. The method obtains the angle 0 between the coordinate axis X and the central regression line R of the five balls S1 to S5. Thereafter, when the gauge 1 is set to be turned over 180 degrees, the minimum plane is passed according to the center coordinates of the balls S1 to S5. Method Obtain the angle 0 'between the coordinate axis X and the five spheres S1 to S5 central regression line R'. Determine the coordinate measuring instrument 2 by calculating (0 — 0 ') / 2 The orthogonality of the instrument axis. In addition, the orthogonality of the remaining five balls S 6 to S 1 0 was measured in the same way as the balls S1 to S 5. The average of the results of the two orthogonality measurements was used to finally determine

Page 18 523579 Case No. 90101765_ Amendment V. Description of the invention (16) The orthogonality of the axes X and γ of the coordinate measuring instrument 2. The above description is directed to the measuring device 1 which is oriented on the coordinate measuring device 2 as shown in FIG. 10A. In addition, a gauge 1 may be provided in the direction shown in FIG. 10B, wherein the direction of the gauge 1 is rotated 90 degrees relative to the direction of the gauge 1 in FIG. 10A in the X-Y plane. The arrangement shown in Fig. 10B is used to determine the straightness of the instrument axis in the Y-axis direction. In addition, the meter 1 may be set in an upright position as shown in FIG. 10C to determine the deflection of the instrument axis Z in the direction of the axis X and the orthogonality of the two axes Z and X. In addition, the gauge 1 can be set in an upright position as shown in FIG. 10D, where the upright gauge is rotated 90 degrees about the axis Z relative to the arrangement shown in FIG. 10C in order to determine the instrument axis in the Y direction of the axis The skewness of Z and the orthogonality of the two axes Y and Z. Figure 11 shows a perspective view of another embodiment of a coordinate measuring machine gauge according to the present invention. In Fig. 11, the meter 1 'has a bracket 10' having a parallelepiped shape and a flat block having an isosceles trapezoidal through-hole 10'A. The balls 11 are the same as the previous embodiment, and are arranged on the opposite inclined surfaces of the trapezoidal through-holes 10'A and are arranged along a line parallel to the inclined surfaces. The centers of the balls 11 are aligned in a straight line and extend along a straight line parallel to the opposite slopes of the through holes 10'A. In the embodiment shown, five balls 11 are arranged on each slope and spaced equally apart. In the coordinate measuring instrument Γ in this embodiment, a direction perpendicular to a virtual reference plane including a line on which the balls 11 are lined up, and a thickness direction of a block constituting the bracket 10 ′ Same, reference axis is perpendicular

Page 19 523579 Case No. 90101765 Λ_η Amendment 5. Explanation of the invention (17) The upper and lower sides of the bracket 1 0 ′ and the upper and lower sides of the trapezoidal through hole 10 A ′. It should be noted that, similar to the gauge 1 in the previous embodiment, by changing the position of the clip 12 and, if necessary, changing the positions of the pins 13 and the mounting jig 5 shown in FIG. 4, the coordinate measuring instrument can be measured. The device Γ is set on the coordinate measuring instrument 2 shown in FIG. 1. As can be understood from the above description, according to the present invention, the coordinate data of the measurement accuracy between two points in the coordinate measuring instrument, the straightness of the instrument axis, and the orthogonality between the instrument axes can be obtained at one time. In this way, the measurement error of the measurement device can be effectively measured. Further according to the present invention, when the gauge is set with the front side facing upward and the gauge is turned over with the back side facing upward, the inherent error of the coordinate measuring instrument can be removed from the obtained measurement value, so that the instrument of the coordinate measuring instrument can be accurately measured Shaft straightness. According to the present invention, when the gauge is set with the front side facing upward and the gauge is turned over with the back side facing upward, the inherent error of the coordinate measuring instrument can be removed from the obtained measurement value, so that the instrument of the coordinate measuring instrument can be accurately measured. Axis orthogonality. According to the present invention, it is possible to easily and accurately obtain the accuracy of the distance between the two points in the coordinate measuring instrument and the orthogonality data between the instrument axes. As a result, an inexpensive coordinate measuring machine can be obtained. According to the specific feature of the present invention, the balls are arranged on the opposite inclined surfaces of the trapezoidal blocks constituting the bracket, so the number of measurement points can be increased, and the error measurement of the coordinate measuring instrument can be completed more accurately. According to an embodiment of the present invention, when the balls are arranged in the

Page 20 523579 _Case No. 90101765_Year_Month__ V. Description of the invention (18) In the trapezoidal through hole, not only the ball can be protected, but also the weight of the bracket can be reduced. Since the above description applies to a specific embodiment of the present invention, it should be understood that many variations can be made without departing from the spirit of the invention. The scope of the additional application patent is intended to include modifications that fall within the scope and spirit of the invention. Therefore, the disclosed embodiments of the present invention are considered in all aspects as exemplary rather than limiting. The scope of the present invention is described by the scope of patent application rather than the above description, so it is intended to include all Any modification of this creation in the same creative spirit

Page 21 523579 Amendment No. 90101765 Brief Description of the Drawings Brief Description of the Drawings The invention will be described in detail below with reference to the drawings, in which: FIG. 1 is a perspective view of a coordinate measuring machine gauge mounted on a coordinate measuring machine according to the present invention; 2 is an enlarged view of a probe for a coordinate measuring instrument according to the present invention; FIG. 3 is a perspective view of a measuring instrument connected to a mounting bracket for a coordinate measuring instrument according to the present invention; FIG. 4 is a perspective view of a mounting fixture according to the present invention The coordinate measuring instrument gauge can be connected to the fixed frame; FIG. 5 is a plan view of the coordinate measuring instrument gauge according to the present invention; FIG. 6 is an embodiment view of a method for measuring a sphere center according to the present invention; FIG. 7 is a measuring sphere according to the present invention An embodiment view of a method for spacing between centers, FIG. 8 is an embodiment view of a method for determining flatness in the X-axis direction; FIG. 9 is an embodiment view of a method for measuring orthogonality of an axis according to the present invention, FIG. 1 0 Α and 10B are schematic diagrams of connecting the coordinate measuring instrument with the coordinate measuring instrument according to the present invention when the gauge is in a horizontal position; FIG. 10C and 10D are according to the present invention. Ming coordinate measurement device is a schematic view of the meter is connected to the upright position coordinate measurement device; and FIG. 11 is a perspective view of an embodiment according to the present invention, the coordinate measuring instrument gauge to another embodiment. Schematic element symbol 1

Page 22 523579 Case No. 90101765 Revised

Page 23

Claims (1)

523579 Case No. 90101765 _A. Amendment 6. Scope of patent application 1 · A method for measuring measurement errors in a coordinate measuring instrument, in which the probe head moves relative to the object to be measured along three mutually orthogonal instrument axes, including: In a step, the measuring instrument gauge is placed on the measuring table of the coordinate measuring instrument, the gauge has a plurality of balls, and the center of the ball is arranged at least in a line on a straight line inclined with respect to the reference axis of the gauge. The reference axis is in a virtual reference plane and extends along the virtual reference plane. The gauge is set so that the virtual reference plane is parallel to one of the three instrument axes of the coordinate measuring instrument and the virtual reference plane is left with the rest of the coordinate measuring instrument. Any two axes of the two instrument axes are parallel; in the second step, the coordinates of each ball center relative to the two instrument axes are measured by the measuring instrument; in the third step, the gauge is rotated 180 degrees around the reference axis, and The gauge is placed on the measuring table of a coordinate measuring instrument; and the fourth step is to use the measuring instrument to measure the coordinates of the center of each ball with respect to the two instrument axes. 2. The method according to item 1 of the scope of patent application, wherein one of the two instrument axes is an X instrument axis and the other axis of the two instrument axes is a Y instrument axis, further comprising: according to the second step The Y instrument axis coordinates of the ball center obtained in the direction perpendicular to the reference axis of the gauge and the Y instrument axis coordinates of the ball center obtained in the fourth step are used to determine the measured straightness of the X instrument axis. The determining step includes: in a first calculating step, calculating a difference between Y instrument coordinates of all balls obtained in the second and fourth steps; Page 24 523579 Amendment No. 90101765 6. Scope of patent application Determine the value in the first calculation step; and in the second calculation step, calculate the difference between the maximum and minimum values. 3. Calculate the first regression line from the coordinates obtained in the second step as described in item 1 of the scope of the patent application, from which the angle is 0; calculate the second regression line from the coordinates obtained in the fourth step, from which the angle is 0 ' ; And by calculating the mutual orthogonality of the two instrument axes of the 0-0 'line 4 · A coordinate measuring instrument measuring device, the measuring instrument includes a probe; a plurality of balls, which are connected to the probe head to support the The support of the ball is such that the inclined reference axis is located in the virtual reference plane along the virtual reference axis, and the virtual reference plane is parallel to one of the two instrument axes. 5 · As mentioned in the fourth patent scope A line includes two lines, and the maximum and minimum differences of all the balls obtained by the branch are calculated in the most determined method in the determining step, further comprising: calculating a first regression line with respect to the ball centers of the two instrument axes And the reference axis with respect to the center of the ball relative to the two instrument axes to calculate the second regression line between the reference axis and the reference axis) / 2 in order to determine the level with the virtual reference plane for the needles along at least two instrument axes A probe, the gauges are arranged in contact with each other; and the center of the ball extends along a line extending from at least one inclination plane, the reference bracket can be connected to a coordinate measuring instrument, two instrument axes, and the reference axis A parallel gauge, wherein said at least frame is formed by a trapezoid having two non-parallel sides Page 25 523579 _Case No. 90101765_Year Month and Day _i ± L · _ VI. Patent application block structure, each side is parallel to one of two lines; the balls are arranged and fixed along the two lines . 6. The meter according to item 4 of the scope of patent application, wherein said at least one line includes two lines; said bracket is composed of a block having a trapezoidal through hole with non-parallel sides, each side being parallel to One of the two lines; the balls are arranged and fixed along the two lines. Page 26