JP2005037353A - Width measuring method and surface property measuring equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide equipment capable of precisely, accurately, easily measuring width, thickness, height, depth, and diameter at a complicated characteristic part, such as a recess like a groove, or the like on a complicated work and a projection like a collar, or the like, by surface property measuring equipment and a method. <P>SOLUTION: A procedure is provided. In the procedure, the measured result of the first surface of the work in the first attitude of a detector and that of the second surface of the work in the second attitude of the detector are obtained by the surface property measuring equipment equipped with the detector capable of taking a plurality of measuring attitudes to the work before width data are calculated, based on a designated point in the data of the measured result of the first surface of the work and a corresponding point in the measured data of the second surface of the work. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a width measuring method using a surface texture measuring instrument, and more particularly to a width measuring method for measuring the width of an object to be measured by a surface texture measuring instrument equipped with a detector capable of changing a measuring posture.

  Detectors used in surface texture measuring machines such as roundness measuring machine, surface roughness measuring machine, contour shape measuring machine, etc. have a structure in which a stylus is provided at the tip of a lever that can swing in the direction perpendicular to the workpiece surface. The measurement data is obtained by collecting data by scanning the detector in the direction of the surface of the workpiece while the stylus is in contact with the surface of the workpiece. Measure.

However, the detector of this structure is a single axis that detects irregularities in the swinging direction (up and down Z-axis direction for surface roughness measuring instruments and contour shape measuring machines, and front and rear X-axis direction for roundness measuring machines). Because it is a detector, it is extremely accurate in detecting the unevenness in the swing direction, but it is difficult to obtain workpiece surface data in the swing orthogonal direction (work surface direction) with high accuracy. In general, it is difficult to directly detect a shape feature point portion such as a 90 ° angle. In particular, the width of a concave portion such as a groove provided on the workpiece surface or the width of a convex portion. It was difficult to accurately determine (For example, Patent Document 1)
Further, since there is a restriction on the relative posture of the detector and the relative scanning direction with respect to the workpiece, it is not possible to perform highly accurate scanning on any workpiece surface.
Furthermore, since the measurable area is limited by the interference between the structural members of the measuring instrument and the workpiece, there is a problem in that it is not always possible to measure an arbitrary part of the workpiece.

JP-A-2001-343228

  As a result, when it is necessary to measure with high accuracy, the width of these workpieces can be measured by resetting the workpiece on a different dedicated measuring machine, in addition to measuring the contour and roundness of the workpiece surface using a surface texture measuring machine. It is necessary to separately measure the diameter and the diameter, and accordingly, the measurement setup and the measurement time are increased, resulting in a decrease in the measurement efficiency of the entire workpiece measurement.

In order to solve such a problem, the present invention provides a width measuring method for measuring the width of an object to be measured by a surface texture measuring instrument equipped with a detector capable of changing a measuring posture, and width measurement by this width measuring method. Provided is a surface texture measuring machine that can be used.
Also provided are a surface texture measuring instrument that can alleviate restrictions on the relative scanning direction of the detector with respect to the workpiece and the measurable area, and a width measuring method using the surface texture measuring instrument.

  In order to achieve the above object, a width measuring method according to the present invention includes a surface texture measuring machine equipped with a detector capable of changing a relative measurement posture with respect to the object to be measured to scan the surface of the object to be measured. A width measurement method for measuring width based on the measurement data, the first calibration step for holding the detector in a first posture and calibrating the detector in the posture, and the detection A second calibration step in which the detector is held in a second posture and the detector is calibrated in the posture, and a first measurement is performed by scanning the first surface of the object to be measured in the first posture of the detector. A first measurement step for obtaining data; a second measurement step for obtaining second measurement data by scanning the second surface of the object to be measured with the second posture of the detector; and the first measurement data and the Width data is obtained by performing width calculation processing based on the second measurement data A calculation step, characterized in that it comprises a and a width statistics to obtain the width measurement results by performing statistical processing on the width data.

Here, the detector capable of changing the relative measurement posture refers to a detector capable of changing the relative posture with respect to the measurement object (workpiece).
For example, in a conventional roundness measuring machine, a uniaxial detector that detects irregularities in the stylus swing direction detects irregularities in the radial direction of the workpiece (X-axis direction), and further rotates the workpiece and the detector relative to each other. In addition to measuring the roundness and cylindricity of the workpiece outer diameter and inner diameter, it is possible to measure the shape of the cylinder or cylinder surface in the axial direction by performing relative scanning of the detector in the longitudinal direction (Z-axis direction) of the workpiece. In this case, the relative posture of the workpiece and the detector is the same.

On the other hand, a detector capable of changing the measurement posture can measure differently depending on other postures.
For example, it is possible to detect unevenness in the workpiece radial direction (X-axis direction) and to perform relative detector scanning in the Y-axis direction of the workpiece. In addition, it is possible to detect unevenness in the longitudinal direction (Z-axis direction) of the workpiece and to perform relative detector scanning in the X-axis direction or the Y-axis direction.

  According to the present invention, the detector is held in the first posture, and the first measurement data is obtained based on the calibration result performed in the posture. Similarly, the detector is held in the second posture, and second measurement data is obtained based on the calibration result performed in the posture. And width calculation processing is performed based on these 1st measurement data and 2nd measurement data, and width data is obtained. Further, statistical processing is performed on the width data to obtain a final width measurement result. The width of the recesses such as grooves on the workpiece surface and the width of the projections are opposite to each other in the measurement direction. And measure with high precision unevenness detection. Since the width data is obtained from both measurement results with high accuracy, it is possible to obtain width data with high accuracy.

Further, since statistical processing can be performed on this highly accurate width data, a highly accurate width measurement result can be obtained based on a highly accurate statistical processing result.
Further, in the width measuring method according to the present invention, the width calculating step searches for a corresponding point in a specified direction from the specified point in the first measurement data, and searches the corresponding point from the specified point. It is preferable to include a search step for calculating the distance up to as a width and a control step for executing the search step once or changing the designated point a plurality of times.

  As a result, any data in the first measurement data is designated as a designated point, the second measurement data in any direction designated from this designated point is searched to find a corresponding point, and the distance from the designated point to the corresponding point is represented by a width. Since the same processing can be repeated by designating different designated points, it is possible to compute the width at an arbitrary location based on the first measurement data. Furthermore, if necessary, if there is a part in the first measurement data that is desired to be excluded from the width calculation, the width calculation can be prevented from being performed at the specific part.

Thus, since the width in the designated direction can be measured, the required width can be accurately measured even when the direction of the groove or the convex portion does not coincide with the coordinate axis direction.
Further, in the width measurement method according to the present invention, the width calculation step searches the corresponding point of the shortest distance from the designated point in the first measurement data and searches for the corresponding point from the designated point. It is preferable to include a search step for calculating the distance up to as a width and a control step for executing the search step once or changing the designated point a plurality of times.

As a result, any data in the first measurement data can be designated as a designated point, and the corresponding point of the shortest distance from this designated point can be searched for from the second measured data, and the distance from the designated point to the corresponding point can be calculated as the width. Furthermore, since the same processing can be repeated by designating different designated points, it is possible to calculate the width at an arbitrary location based on the first measurement data. Furthermore, if necessary, if there is a portion in the first measurement data that is desired to be excluded from the width calculation, the width calculation can be prevented from being performed at that specific location.
By searching for the corresponding point at the shortest distance from the designated point in this way, for example, in the groove width, the width of the narrowest portion can be obtained with high accuracy. Moreover, about the thickness of a convex part, the thickness of the thinnest part can be calculated | required accurately.

  Further, in the width measuring method according to the present invention, the width calculating step sequentially obtains an inscribed circle inscribed in the first measured data and the second measured data, and the locus of the center of the inscribed circle is defined as a center line. A center line calculation step, a designated point in the first measurement data and a corresponding point in the second measurement data in a direction perpendicular to the center line, and a distance from the designated point to the corresponding point And a control step for executing the search step a plurality of times.

In this way, an inscribed circle inscribed in the first measurement data and the second measurement data is sequentially obtained, and the locus of the center of the inscribed circle is set as the center line, and the designated point in the first measurement data in the direction perpendicular to the center line. And corresponding points in the second measurement data are searched. Then, the distance from the designated point found to the corresponding point is calculated as a width.
Thus, since the width data in the direction orthogonal to the center line based on the inscribed circle is obtained, for example, the width data of the ball groove in the ball screw can be obtained with high accuracy.

  In the width measuring method according to the present invention, the width calculating step sequentially obtains an inscribed sphere inscribed in the first measurement data and the second measured data, and a center formed from a center coordinate of the inscribed sphere. A center plane calculating step for calculating a plane; searching for a designated point in the first measurement data and a corresponding point in the second measurement data in a direction orthogonal to the center plane; and from the designated point to the corresponding point It is preferable to include a search step for calculating the distance as a width and a control step for executing the search step a plurality of times.

Thus, when the surfaces can be defined by the first measurement data and the second measurement data, the inscribed spheres inscribed between the respective surfaces are sequentially obtained, and the center surface formed from the center coordinates of the inscribed spheres A specified point in the first measurement data and a corresponding point in the second measurement data in a direction orthogonal to the normal direction (normal direction) are searched. Then, the distance from the designated point found to the corresponding point is calculated as a width.
Thus, since the width data in the normal direction of the center plane based on the inscribed sphere is obtained, for example, the thinnest portion between the faces can be obtained with high accuracy in the convex portion.

In the width measuring method according to the present invention, it is preferable that the width statistical step obtains at least one of a maximum value, a minimum value, and an arithmetic average value when the width data includes a plurality of data. .
As a result, a highly accurate statistical feature value can be obtained based on a plurality of width data.
Further, these width measuring methods are preferably carried out in a surface property measuring machine such as a surface roughness measuring machine, a surface shape measuring machine, or a roundness measuring machine.
As a result, surface texture measurement and width measurement can be performed with the same measuring machine, so there is no need to change work placement, measurement setup can be shortened, and overall measurement and evaluation time can be shortened. Become.

  In order to achieve the above object, a surface texture measuring machine according to the present invention includes a rotary table on which an object to be measured is rotatably mounted, and a Z that is movable in a Z-axis direction parallel to the rotational axis of the rotary table. An axis slider, an X-axis slider held by the Z-axis slider and capable of advancing and retreating in the X-axis direction orthogonal to the rotation axis, and a center line A held by the X-axis slider and parallel to the X-axis A first arm that can rotate about the first arm, a second arm that is held by the first arm and can be advanced and retracted in a direction perpendicular to the X axis, and a second arm that is held by the second arm. And a detector for measuring surface properties.

Here, the second arm does not necessarily have to be in a direction orthogonal to the X axis, and may be capable of moving back and forth in a direction inclined to the X axis orthogonal plane.
Further, it is preferable that the amount of movement of the Z-axis slider, the amount of advance / retreat of the X-axis slider, the amount of rotation of the first arm, and the amount of advance / retreat of the second arm can be measured.
According to the present invention, since the relative posture of the detector with respect to the workpiece and the degree of freedom in the relative scanning direction are improved, it is possible to perform highly accurate scanning on any workpiece surface.
Furthermore, since interference between each structural member of the measuring machine and the workpiece can be avoided, the measurable area is widened, and an arbitrary portion of the workpiece can be measured.

Furthermore, the surface texture measuring instrument according to the present invention is characterized in that the detector is held rotatably about a center line B parallel to the advancing / retreating direction of the second arm.
Here, the center line B is preferably orthogonal to the X axis, but is not necessarily orthogonal. Further, it is preferable that the amount of rotation around the center line B of the detector can be measured.
Moreover, it is preferable that the axis of the stylus that is substantially orthogonal to the detection direction of the detector (the direction in which the unevenness of the workpiece is detected) and that has a probe at the tip is substantially parallel to the center line B. This prevents the stylus tilt from changing even when the detector is rotated.
According to the present invention, since the detector is rotatably held, the detection direction of the detector can be directed in an arbitrary direction, so that the measurement accuracy and flexibility are improved.

The width measurement method according to the present invention includes a first measurement step of obtaining first measurement data by scanning the first surface of the measurement object with the detector, and a first measurement of the measurement object with the detector. A second measurement step of obtaining second measurement data by scanning two surfaces, and a width calculation step of obtaining width data by performing width calculation processing based on the first measurement data and the second measurement data. It is characterized by that.
Here, the first surface and the second surface are in a relative positional relationship, for example, the left inner surface and right inner surface of the upright cylindrical inner diameter, the left outer surface and right outer surface of the upright cylinder, and the upper and lower surfaces of the horizontal flange Etc.
In addition, after the measurement in the first measurement step, the detector is moved by, for example, Z-axis slider movement, X-axis slider advance / retreat, second arm advance / retreat, and the measurement is performed in the second measurement step. Furthermore, the detector posture in the first measurement step and the detector posture in the second measurement step do not have to be the same. For example, the posture is changed by the rotation of the first arm and the rotation of the detector with respect to the second arm. May be.

According to this invention, for example, the left outer surface and the right outer surface of the upright cylinder can be measured by scanning in various directions such as the Z-axis direction or the Y-axis direction orthogonal to the Z-axis and the X-axis, respectively. The degree of freedom of measurement is improved.
Further, the width measurement method according to the present invention obtains a maximum value or a minimum value from each of the first measurement data and the second measurement data in the width calculation step, and based on the maximum value or the minimum value, The diameter value of the object to be measured is used as width data.
According to this invention, for example, the diameter of the cylinder is calculated from the difference between the maximum value obtained from the first measurement data obtained by measuring the right outer surface of the upright cylinder and the minimum value obtained from the second measurement data obtained by measuring the left outer surface. The value can be easily obtained.

Further, the width measurement method according to the present invention includes a calibration step for calibrating the detector, a measurement step for obtaining measurement data by scanning the surface of the object to be measured by the detector, and a maximum value from the measurement data. Or a width calculation step of obtaining a minimum value and using the diameter value of the object to be measured as width data based on the maximum value or the minimum value.
Here, the calibration of the detector means to calibrate the coordinate value of the probe of the detector. For example, in the X-axis direction, when the probe measures the axial center position of the rotary table, the X-axis Calibrate the detector so that the coordinate value of becomes zero.
According to the present invention, for example, after the measurement data is obtained by scanning the right outer surface of the cylinder in the Y-axis direction with a coordinate-calibrated detector and then obtaining the maximum value from the measurement data, the radius value is obtained immediately. Therefore, the radius value can be doubled to obtain the diameter value, and the width dimension can be measured very easily.

According to the width measuring method according to the present invention, the width, thickness, height, depth of a complicated characteristic part such as a concave part such as a groove on a complicated workpiece or a convex part such as a collar, or an inner diameter value such as a cylinder, The outer diameter value (diameter value) can be accurately and easily measured.
Further, according to the surface texture measuring instrument according to the present invention, the relative posture of the detector with respect to the workpiece and the degree of freedom in the relative scanning direction are improved, so that it is possible to perform scanning with high accuracy on any workpiece surface. In addition, since the interference between the structural members of the measuring machine and the workpiece can be avoided, the measurable region is widened, and an effect is obtained that it is possible to measure an arbitrary portion of the workpiece.

  Preferred embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a schematic configuration of a roundness measuring device 1 according to a first embodiment of the present invention.
The roundness measuring machine 1 shown in FIG. 1 includes a rotary table 10 on the upper end side of a base 2 on which a work W is rotatably mounted and rotated about an axis C.
Further, a vertical support column 3 is provided on the other upper end side of the base 2, and a Z-axis slider 4 is held along the support column 3 so as to be slidable in the vertical direction (Z-axis direction). The Z-axis slider 4 holds the X-axis slider 5 so as to be slidable in the left-right direction (X-axis direction).

  A first arm 6 is provided on the rotary table 10 side (the left end in the figure) of the X-axis slider 5. It is held rotatably. Further, the first arm 6 slidably holds one end of the second arm 7, and the sliding direction is the vertical direction in the state shown in FIG. 1 and the same direction as the Z-axis direction. However, when the first arm 6 is rotated 90 ° from the state shown in FIG. 1, the first arm 6 is in a horizontal state, and the sliding direction of the second arm 7 is the vertical direction in FIG. Become a direction.

A detector main body 8 is held on the other end side of the second arm 7 so as to be rotatable about the center line B. A pivotable lever having a spherical stylus 9 protrudes from the detector body 8 at the tip (lower end in the figure), and the pivoting direction is the left-right direction (X-axis direction) in the state of FIG. In this state, the stylus 9 can detect irregularities in the X-axis direction.
In addition to the detector provided with the stylus 9, the roundness measuring machine 1 is provided with various detectors (not shown). The movement amount of the Z-axis slider 4 (Z-axis movement amount), the X-axis slider 5. , The amount of rotation of the first arm 6, the amount of movement of the second arm 7, the amount of rotation of the detector body 8, and the amount of rotation of the rotary table 10 are detected with a predetermined accuracy.

Further, in this roundness measuring device 1, a Z-axis drive mechanism for moving the Z-axis slider 4 in the vertical direction, an X-axis drive mechanism for moving the X-axis slider 5 in the horizontal direction, and the first arm 6 are rotated. A first arm rotating mechanism, a second arm driving mechanism for driving the second arm 7, a detector rotating mechanism for rotating the detector main body 8, and a rotating table rotating mechanism for rotating the rotating table 10 are shown. Is omitted.
FIG. 2 is a block diagram of a roundness measuring system including a roundness measuring machine 1 and a computer 100 that performs control and data processing thereof.

Each drive mechanism and rotation mechanism of the roundness measuring machine 1 is connected to a control device 101 including a drive amplifier and a DA conversion circuit, and is controlled to a predetermined positioning position, positioning angle, and positioning speed. Further, each movement amount and rotation amount detected and output by each detector is connected to a detection input device 102 including an input amplifier and an AD conversion circuit, and input processing is performed.
The computer 100 further includes a central processing unit 103 that performs various types of data processing, a storage device 104 that stores data, a keyboard, a mouse, or a joystick that inputs commands from an operator, a display device that outputs data processing results, and printing. Also included is an input / output device 105 for inputting / outputting commands and data to the central processing unit 103 such as data input / output with the device.

The normal measurement in the roundness measuring machine 1 can be manual measurement and automatic measurement.
The manual measurement procedure is as follows. First, the first arm 6 and the detector main body 8 are held in the state shown in FIG. 1, and the X-axis slider 5 is manually moved with a joystick or the like so that the stylus 9 contacts the workpiece W. Advance in the direction. When the stylus 9 (measuring element) contacts the workpiece W, the X-axis slider 5 is stopped and the rotary table 10 is rotated. Then, as the turntable 10 rotates, the swing of the stylus 9 following the surface irregularities of the workpiece W is detected, and the output of the detector is input from the detection input device 102.

When the data collection is completed, the rotation of the rotary table 10 is stopped, the roundness of the workpiece W is calculated by performing various processes on the collected data, and the result is displayed on the display device of the input / output device 105. indicate.
When automatic measurement is performed, the central processing unit 103 executes a part program created using a keyboard or input from an external device.

  Various measurement operations can be performed depending on the contents of this part program.For example, the procedure shown in the manual measurement described above can be automatically processed. In this case, the operator can specify the part program and start execution. In this case, after that, operator intervention during the measurement is unnecessary, so that the measurement efficiency is improved. In this part program, various measurement operations according to the workpiece to be measured are described in advance, so that various workpiece measurements can be automated.

When the width measurement according to the present invention is performed by the roundness measuring device 1, the measurement process is performed according to the procedure shown in the flowchart of FIG. 3. In this case, either the manual measurement or the automatic measurement by the part program is performed. good.
First, width measurement processing is started in step 10 (S10).
Next, the calibration reference jig 20 is placed on the turntable 10. As shown in FIG. 4, the calibration reference jig 20 is composed of an upright column 21, an inclined column 22, and a reference sphere 23, and the sphericity of the reference sphere 23 is guaranteed with a required accuracy. When the calibration reference jig 20 is placed on the turntable 10, the center of the reference sphere 23 coincides with the rotation axis C of the turntable 10 by a positioning jig (not shown), and the center coordinates of the reference sphere 23 also have a predetermined value. Is placed as follows.

Thereafter, the first arm 6 and the detector main body 8 are rotated and the Z-axis slider 4, the X-axis slider 5, and the second arm 7 are moved so that the detector main body 8 and the stylus 9 are as shown in FIG. , The first posture (detector body 8a and stylus 9a). In this posture, the second arm is moved so that the stylus 9a scans around the top of the reference sphere 23 to obtain a detection result. Since the detection result is arc-shaped data, the center of the reference sphere 23 is calculated by analyzing these data.
Here, since the radius and center coordinates of the reference sphere 23 are known, the tip radius of the stylus 9 and the center position of the stylus 9 are calibrated and the first calibration step is completed (S20).

Next, similarly, as shown in FIG. 4, the stylus 9 is set in the second posture (the detector main body 8b and the stylus 9b), and the same calibration process as that in the first calibration step is performed for the second posture. The process ends (S30).
Next, the workpiece W is placed on the turntable 10. At this time, adjustment is performed by a centering mechanism and a leveling mechanism (not shown) so that the axis of the workpiece W coincides with the axis C of the rotary table 10 (S40).
The measurement is detected in the second measurement step (S60) after the detector is held in the first posture in the first measurement step (S50), the first surface W1 of the workpiece W is scanned to obtain the first measurement data. The instrument is held in the second posture and the second surface W2 of the workpiece W is scanned to obtain second measurement data.

At this time, the first measurement data is obtained by reflecting the calibration result in the first calibration process in the data obtained in the first measurement process, and the calibration result in the second calibration process is reflected in the data obtained in the second measurement process. Second measurement data is obtained.
5 to 10 show how the first measurement data and the second measurement data are collected in the first measurement process and the second measurement process.
FIG. 5 shows measurement for obtaining point data on the XY plane, and the Z-axis data of only one point P1 is collected on the first surface W1 of the workpiece W by the first attitude of the detector (first measurement step), and thereafter In the second surface W2 of the work W, Z-axis data of only one point P2 in the same X coordinate value and Y coordinate value as the point P1 is collected by the second attitude of the detector (second measurement step).

In this case, the Z coordinate value of the collected data is a composite value of the movement amount of the Z-axis slider 4 and the detection amount of the detector (the swing amount of the stylus 9). This point is a modification of FIGS. 6 and 7 below. The same applies to the examples.
FIG. 6 shows measurement for obtaining line data in the XY plane. In the first measurement step, the second arm 7 is moved on the first surface W1 of the workpiece W with the point P1 as the starting point in the first posture of the detector. The detector is scanned to collect L1 line data. In the second measurement step, a point P2 (X coordinate value and Y coordinate value may be the same as the point P1) in the second posture of the detector on the second surface W2 of the workpiece W is used as a start point. The arm 7 is moved to scan the detector, and L2 line data is collected.

FIG. 7 shows measurement for obtaining surface data in the XY plane. In the first measurement step, the rotary table 10 is rotated with the point P1 as the starting point in the first posture of the detector on the first surface W1 of the workpiece W. Rotate the workpiece W to cause the detector to scan relative to the workpiece W, and collect C1-1 circle data.
Next, circle data of C1-2,..., C1-n are similarly collected from different starting points in the radial direction of the workpiece W. In the second measurement step, the point P2 (X coordinate value and Y coordinate value may be the same as the point P1) is set as the start point in the second posture of the detector on the second surface W2 of the workpiece W, and similarly Collect C2-1 circle data. Next, circle data of C2-2, C2-n are collected in the same manner from different starting points in the radial direction of the workpiece W.

FIG. 8 shows measurement for obtaining point data in the radial direction of the workpiece W, and X-axis data of only one point X1 on the first surface W1 which is the inner diameter of the workpiece W is collected by the first posture of the detector (first Measurement step), and thereafter, the X-axis data of only one point X2 on the second surface W2 that is the outer diameter of the workpiece W is the same as the point X1 and the Z coordinate value is collected by the second posture of the detector. (Second measurement step).
The second posture of the detector when obtaining the radial data of the workpiece W is the same as the posture of the detector shown in FIG. 1, and the first posture is the position of the detector body 8 relative to the second posture. This is a posture rotated by 180 ° around the center line B. The first posture and the second posture in the measurement in the radial direction of the workpiece W are the same in the description of FIGS. 9 and 10 below.

In this case, the X coordinate value of the collected data is a composite value of the movement amount of the X-axis slider 5 and the detection amount of the detector (the swing amount of the stylus 9). This point is the following modification of FIG. 9 and FIG. The same applies to the examples.
FIG. 9 shows measurement for obtaining line data in the radial direction of the workpiece W. In the first measurement step, the second arm 7 starts from the point X1 in the first posture of the detector on the first surface W1 of the workpiece W. Is moved to scan the detector and Lx1 line data is collected. In the second measurement step, the point X2 (X coordinate value and Y coordinate value may be the same as the point X1) in the second posture of the detector on the second surface W2 of the workpiece W is used as the start point. The arm 7 is moved to scan the detector, and Lx2 line data is collected.

FIG. 10 shows measurement for obtaining surface data in the radial direction of the workpiece W. In the first measurement step, the point X1 is set as the starting point in the first posture of the detector on the first surface W1 of the workpiece W, and the rotary table 10 is set. By rotating the workpiece W, the detector is scanned relative to the workpiece W to collect Cx1-1 circle data.
Next, circle data of Cx1-2, Cx1-n are collected in the same manner from different starting points in the Z-axis direction of the workpiece W. In the second measurement step, on the second surface W2 of the workpiece W, the point X2 (X coordinate value and Y coordinate value may be the same as the point X1) in the second posture of the detector is set as the starting point, and similarly Collect Cx2-1 circle data. Next, circle data of Cx2-2, Cx2-n are collected in the same manner from different starting points in the Z-axis direction of the workpiece W.
After the data is collected by the first and second measurement processes, the width data is calculated by the width calculation process (S70).

  The simplest width data calculation is to calculate the difference between the Z-axis coordinate values of the first measurement data P1 and the second measurement data P2 obtained in FIG. In this case, since the X coordinate value and the Y coordinate value of the point P1 and the point P2 are the same, the point P2 (corresponding point) exists in the Z-axis direction when viewed from the point P1 (designated point). Accordingly, the width in the Z-axis direction (also referred to as thickness in the case of FIG. 5) can be calculated simply by calculating the difference between the Z-axis coordinate values of both points (designated point and corresponding point). (In this case, of course, it is meaningless to specify a direction other than the Z-axis direction.)

  The same calculation is possible for the calculation of the width data for the line data L1 and L2 obtained in FIG. 6, but in this case, since it is line data (a plurality of point sequence data), first, in the line data L1, a designation is made. Point a1 is determined. The designated point a1 may designate only one point in the line data L1, but for example, as shown in FIG. 11, every other point sequence data constituting the line data L1 is a0, a1, a2,. In addition, all the point sequence data constituting the line data L1 may be designated as designated points.

  When a designated point (eg, a1) is designated, a corresponding point (eg, b1) corresponding to this designated point is searched from the point sequence data constituting the line data L2. As this search method, as shown in FIG. 12, there is a method of searching for the corresponding point b1 existing in the specified direction from the specified point a1 from the line data L2. For example, the corresponding point b1 existing in the Z-axis direction from the specified point a1 Ask for. Further, as shown in FIG. 13, there is a method of searching for the corresponding point b1 existing at the shortest distance from the designated point a1 from the line data L2.

Further, as shown in FIG. 14, the inscribed circle Ic inscribed in the line data L1 and the line data L2 is sequentially calculated, and the center line L3 is obtained from the point sequence constituted by the center Pc of the inscribed circle Ic. There is a method of searching for a point on the line data L1 in a direction orthogonal to the center line L3 at an arbitrary point (s) of the line L3 as a designated point a1 and a point on the line data L2 as a corresponding point b1.
Regarding the calculation of the width data for the surface data obtained from FIG. 7 or FIG. 10, in addition to the search method of FIG. 12 to FIG. 14, the method using the inscribed circle in FIG. Search with a simple inscribed sphere.

In this case, first, a first surface S1 corresponding to the first surface W1 of the workpiece W is calculated based on the first measurement data, and a second surface S2 corresponding to the second surface W2 is calculated based on the second measurement data. To do. Next, an inscribed sphere Is inscribed in the first surface S1 and the second surface S2 is sequentially calculated, and a center surface S3 is obtained from a point sequence formed by the center Ps of the inscribed sphere Is, and the center surface S3 A point on the first surface S1 in a direction orthogonal to the central plane S3 at any point (s) is designated as the designated point a1, and a point on the second surface S2 is searched as the corresponding point b1.
When the designated point a1 and the corresponding point b1 corresponding thereto are searched by these methods, the distance from the designated point a1 to the corresponding point b1 is calculated as the width.

When there are a plurality of designated points, each width is calculated to obtain width data.
After obtaining the width data in the width calculation step (S70), statistical processing is performed on the width data in the width statistics step (S80). When the width data is composed of only one data, the processing in the width statistics process is not performed, but when it is composed of a plurality of data, various statistical processes are performed. As the statistical processing items, extraction of a maximum value or minimum value from a plurality of width data and calculation of a statistical quantity of an arithmetic average value are performed.
When these processes are completed, the first measurement data, the second measurement data, the width data, and the statistics data are displayed on the display device of the input / output device 105 to complete the process (S90).

This embodiment has the following effects.
(1) Since various postures are possible as the first posture and the second posture of the detector, even if it is a single-axis detector, between two points such as width, thickness, height, etc. at an arbitrary position of a complex workpiece Can be easily measured.
(2) Since the calibration result of the detector in the first posture is reflected in the first measurement data and the calibration result of the detector in the second posture is reflected in the second measurement data, highly accurate measurement can be performed. As a result, even when a width is measured based on the first measurement data and the second measurement data, a highly accurate width measurement result can be obtained.

(3) Arbitrary data in the first measurement data is designated as a designated point, the second measurement data in an arbitrary direction designated from this designated point is searched for a corresponding point, and the distance from the designated point to the corresponding point is represented by a width. Therefore, for example, regardless of the direction of the groove to be measured on the workpiece, the width of the groove can be accurately obtained by designating a direction orthogonal to the groove direction.
(4) Since the width is obtained by using an arbitrary point in the first measurement data as the designated point, if there is a part that is not to be subjected to the width calculation, the width calculation can be prevented from being performed at the specific part.

(5) Since the corresponding point of the shortest distance from the designated point in the first measurement data can be searched from the second measurement data and the distance from the designated point to the corresponding point can be calculated as the width, for example, in the groove width The width of the narrowest part can be obtained with high accuracy. As for the thickness of the convex portion such as the flange flange, the thickness of the thinnest portion can be obtained with high accuracy.
(6) Inscribed circles inscribed in the first measurement data and the second measurement data are sequentially obtained, the locus of the center of the inscribed circle is taken as the center line, and the designated point in the first measurement data in the direction perpendicular to the center line Since the distance between the corresponding point in the second measurement data and the corresponding point is calculated as the width, for example, the ball groove width data in the ball screw can be obtained with high accuracy.

(7) When the surfaces can be defined by the first measurement data and the second measurement data, inscribed spheres inscribed between the surfaces are sequentially obtained, and the center surface formed from the center coordinates of the inscribed spheres Since the distance between the specified point in the first measurement data and the corresponding point in the second measurement data in the direction orthogonal to the normal direction is calculated as the width, for example, the thickness distribution in a cylinder or the like is accurately obtained. be able to.
(8) Since a highly accurate statistical feature value can be obtained based on a plurality of width data, it becomes easy to grasp the tendency of the workpiece width measurement result.

Next, a second embodiment according to the present invention will be described.
The surface texture measuring machine (roundness measuring machine) used in Example 2 is substantially the same as Example 1 (FIGS. 1 and 2) as shown in FIG. In FIG. 16, a horizontal cross-sectional main part indicated by DD is shown in FIGS. 17 and 18.
16 differs from FIG. 1 in that the first arm 6 is rotated around the center line A and maintained in a horizontal posture, so the second arm 7 is slidable in the horizontal direction (Y-axis direction). It is. That is, as the second arm 7 slides, the horizontal detector body 8 is advanced and retracted in the Y-axis direction.

The workpiece W shown in FIG. 16 has a flange portion at the top and bottom, and in Example 2, the diameter of the central cylindrical shaft portion sandwiched between the flange portions is measured. With such a specially shaped workpiece, measurement cannot be performed with the orientation of the detector shown in FIG. 1, and thus the measurement is performed by moving the detector body 8 in the horizontal orientation forward and backward in the Y-axis direction.
The stylus 9 in FIG. 1 protrudes leftward (X-axis direction) with respect to the detector main body 8, and detects unevenness in the left-right direction (X-axis direction) on the outer surface of the workpiece W. When the stylus 9 is not in contact with the workpiece W, the steady position of the stylus 9 is the left end in the swing range of the stylus 9.

On the other hand, the detector used in Example 2 shown in FIG. 16 has a stylus 81 on the extension line of the axis of the detector main body 8 as shown in FIG. Yes. As shown in FIG. 17, the stylus 91 is in a steady position with respect to the axial line of the detector 8. The stylus 91 swings in the left-right direction in FIG. That is, when the stylus 91 swings in the right direction, a convex portion in the X axis + direction is detected, and when the stylus 91 swings in the left direction, a concave portion in the X axis-direction is detected.
The width measurement (diameter measurement) according to the present invention using the roundness measuring machine 1 is performed by the procedure shown in the flowchart of FIG. 19. In this case, either manual measurement or automatic measurement by a part program is performed. You can go.

First, measurement is started in S110. At this time, a predetermined measurement preparation process such as placing the workpiece W on the rotary table 10 is already completed.
Next, as shown in FIG. 17, the stylus 91 of the detector is positioned on the right side surface of the workpiece W, and is scanned so as to include the rightmost end of the shaft portion of the workpiece W to obtain the first measurement data L11 (the first measurement data L11). 1 measurement step = S120).
Thereafter, as shown in FIG. 18, the stylus 91 of the detector is positioned on the left side surface of the workpiece W, and is scanned so as to include the leftmost end of the shaft portion of the workpiece W to obtain the second measurement data L12 (second second). Measurement step = S130).

Next, the maximum value a11 is searched from the first measurement data L11, and the minimum value b11 is searched from the second measurement data L12. The first measurement data L11 and the second measurement data L12 are data that accompany the swing of the stylus 91. The X-axis direction position of the detector body 8 in each measurement is determined by the position of the X-axis slider 5. Therefore, when the position of the detector main body 8 in the X-axis direction is added to the stylus 91 swing data, the data shown in FIG. 20 is obtained. In FIG. 20, points a11 and b11 are the maximum value and the minimum value in the X-axis direction of the first measurement data L11 and the second measurement data L12, respectively.
If the difference between the coordinate values in the X-axis direction between the maximum value a11 and the minimum value b11 is obtained based on this result, the diameter of the cylindrical shaft portion of the workpiece W can be obtained (width calculation step = S140).
Thereafter, the process ends (S150).

The second embodiment has the following effects.
(9) Since the measurement data can be obtained by scanning in a predetermined direction while keeping the detector in an optimum posture according to the measurement site of the workpiece, measurement can be performed at an arbitrary position of a workpiece having a complicated shape even with a single axis detector. Can be performed with high accuracy.
(10) In the first measurement step, the detector is positioned at the first position to obtain the first measurement data, and then in the second measurement step, the detector is positioned at the second position to obtain the second measurement data. Thus, the maximum value and the minimum value of each measurement data are searched, and the diameter value of the workpiece is obtained as the width data based on the result, so that highly accurate measurement can be performed.

(11) Since the width data can be obtained by differential processing based on the maximum value and the minimum value of the measurement data, it is not always necessary to calibrate the tip position of the stylus, and high accuracy is achieved despite simple measurement. Can be measured.
(12) Since the inner diameter diameter value and the thicknesses of the thickest part and the thinnest part of the collar portion can be obtained as width data by the same measurement method, measurement can be performed easily and accurately.

Next, a third embodiment according to the present invention will be described.
The surface texture measuring instrument (roundness measuring instrument) used in Example 3 may be either Example 1 (FIGS. 1 and 2) or Example 2 (FIG. 16).
With this roundness measuring instrument 1, the width measurement (diameter measurement) according to the present invention is performed by the procedure shown in the flowchart of FIG. 21. In this case, either manual measurement or automatic measurement by a part program is performed. Also good.

First, measurement is started in S210.
Next, while holding the first arm 6 in the posture shown in FIG. 17, the calibration reference jig 20 is placed on the turntable 10. As shown in FIG. 22, the calibration reference jig 20 includes an upright support column 21, an inclined support column 22, and a reference sphere 23, and the sphericity of the reference sphere 23 is guaranteed with a required accuracy. When the calibration reference jig 20 is placed on the turntable 10, the center of the reference sphere 23 coincides with the rotation axis C of the turntable 10 by a positioning jig (not shown), and the center coordinates of the reference sphere 23 also have a predetermined value. Is placed as follows.

Thereafter, the Z-axis slider 4 is moved up and down while the stylus 9 (91) is in contact with the right end of the reference sphere 23, and Z is moved at a position where the swing output of the stylus 9 (91) becomes maximum in the X-axis direction. Hold the axis slider.
Next, the second arm 7 is moved back and forth in the Y-axis direction, and the second arm 7 is held at a position where the swing output of the stylus 9 (91) becomes maximum in the X-axis direction. The X-axis coordinate of the stylus 9 (91) is calibrated so that the added value of the position 5 and the swing output of the stylus 9 (91) becomes the radius value (diameter value / 2) of the reference sphere 23 (S220). : Calibration process).

Thereafter, the work W is placed on the rotary table 10 instead of the calibration reference jig 20, and the work W is centered and leveled. That is, the axis of the workpiece W is made to coincide with the rotation axis C of the rotary table 10.
Next, as shown in FIG. 17, the stylus 9 (91) of the detector is positioned on the right side surface of the workpiece W and scanned to include the rightmost end of the shaft portion of the workpiece W to obtain measurement data L13 ( Measurement step = S230).

  Thereafter, the maximum value a12 is searched from the measurement data L13. The measurement data L13 is data accompanying the swing of the stylus 9 (91), but the position of the detector body 8 in the measurement in the X-axis direction is determined by the position of the X-axis slider 5, so the stylus 9 (91 ) When the position of the detector body 8 in the X-axis direction is added to the swing data, the data shown in FIG. 23 is obtained. The intersection point O between the X axis and the Y axis in FIG. 23 is the coordinate origin, and coincides with the axis of the workpiece W and the rotation axis C of the rotary table 10. For the workpiece W indicated by a broken line, the measurement data L13 in the measurement process is a solid line portion. Point a12 is the maximum value in the X-axis direction of measurement data L13.

Since the position of the stylus 9 (91) has been calibrated in the calibration step S220, the X-axis coordinate value of the point a12 indicates the radius value of the workpiece W, and this X-axis coordinate value is doubled. A diameter value which is width data of the workpiece W can be obtained (S240: width calculation step).
Thereafter, the process is terminated (S250).

According to the third embodiment, in addition to the effect (9) in the second embodiment, the following effects can be obtained.
(13) Since the position of the stylus is calibrated by the calibration process, if the workpiece is placed so that the axis of the workpiece coincides with the rotation axis of the rotary table, the width and diameter of the workpiece can be measured only once. Since the value can be obtained, the measurement can be performed easily and at high speed.
(14) Since the inner diameter diameter value can be obtained as the width data by the same measuring method, it is possible to easily and accurately measure.

Next, a modified example will be described.
FIG. 24 is the same as the roundness measuring device 1 shown in FIG. 1 except that the detector main body 8 is rotated 180 degrees and the stylus 9 moves in the right direction (X axis + Projecting in the left and right direction (X-axis direction) of the inner surface of the workpiece. The steady position of the stylus 9 when the stylus 9 is not in contact with the workpiece W is the right end in the swing range of the stylus 9.

  In the measurement processing in this modification, in addition to the measurement of the width such as the inner diameter, the inner diameter roundness, the inner diameter cylindricity, and the like can be performed. The feature of this modification is that the second arm 7 can be advanced and retracted, so that the stylus 9 can reach the lower part of the inner diameter of the workpiece W, the measurable area is expanded, and the measurement of an arbitrary portion of the workpiece W can be performed with high accuracy. Is a point. Conventionally, the stylus 9 did not reach the lower inner diameter of the workpiece W due to interference between the X-axis slider 5 and the first arm 6 and the workpiece W. In order to compensate for this, measurement was performed using a long stylus, so ensuring measurement accuracy was a problem, but this point was solved.

As described above, according to the present invention, it is possible to accurately and easily measure the width such as the diameter value of the workpiece, but the present invention is not limited to these examples.
For example, a stylus-type oscillating single-axis detector is shown as the detector. However, the detector is not limited to this, and may be a two-dimensional or three-dimensional scanning detector, and an image for collecting image data optically. A detector, a magnetic type, a capacitance type, or another optical type detector may be used, and the present invention can be carried out regardless of a contact type or non-contact type to a workpiece.
Further, in each example, an example using a roundness measuring detector is shown, but instead of this, a surface roughness measuring detector may be used. Roundness, shape, or dimensions can be measured.

7 or 10, the method based on the circle data is shown as the scanning method for obtaining the surface data. However, the method is not limited to this, and the surface data can also be obtained based on a plurality of line data.
Further, in FIGS. 11 to 13, the example in which the data of each point in the line data is used as the designated point and the corresponding point is shown. However, the interpolation processing is performed on the line data L1 and L2, and the interpolation curve of the line data L1. In the above, a designated point may be provided for each fixed distance, and a corresponding point corresponding to the designated point may be obtained from the interpolation curve of the line data L2.

Moreover, although the roundness measuring machine is shown as a workpiece rotating type, it is not limited to this and may be a detector rotating type.
Furthermore, as the surface texture measuring instrument, an example of implementation on a roundness measuring instrument has been shown, but the present invention is not limited to this, and it can also be implemented on a surface roughness measuring instrument, a contour shape measuring instrument, an image measuring instrument, a three-dimensional measuring instrument, etc. .
Moreover, although the example which a detector can hold | maintain several attitude | positions with respect to the workpiece | work was shown, it may replace with this and a workpiece | work may hold | maintain several attitude | positions.
Further, the lever including the detector or the stylus may be replaceable automatically or manually.
The width measurement method according to the present invention may execute a processing procedure by executing a computer program.

The computer program is not limited to a language format or execution form, and may be any high-level language or intermediate language such as an interpreter form.
Further, the computer program may not be resident in the storage device but may be read via the communication path via the input / output device when necessary. Since the program for executing the width measuring method according to the present invention is simple in calculation processing and suitable for miniaturization, it is also suitable for such an execution form.

  In the second embodiment (FIG. 16) and the third embodiment, the scanning of the stylus 9 (91) is performed in the Y-axis direction. You can decide. As an example, if the first arm 6 is inclined at 45 degrees with respect to the Y axis, scanning in an inclined direction of 45 degrees with respect to the Y axis in the YZ plane is possible. In other words, even a spiral workpiece such as a screw can be measured with high accuracy.

Further, in the second embodiment (FIG. 16) and the third embodiment, only the case of performing the width (diameter value) measurement is shown, but the perfect circle of the cylindrical shaft portion of the workpiece W is determined by the detector posture shown in FIG. Of course, it is possible to measure degrees, cylindricity, straightness in the Z-axis direction, and the like.
Further, the posture of the detector main body 8 shown in FIG. 16 is rotated by 90 degrees about the rotation axis B, and the detection direction of the stylus 9 (91) is set to the Z + direction or the Z− direction. In addition to measuring the upper surface of the part and the lower surface of the collar part to measure the width, one or more of the upper surface of the work W, the upper surface of the collar part, and the lower surface of the collar part in the Y-axis direction by the stylus 9 (91) The straightness and flatness can also be measured by scanning the location.

  In the measurement of the cylindrical inner diameter portion shown in FIG. 24, the inner diameter surface of the workpiece W can be scanned by causing the stylus 9 (91) to scan in the tilt direction or the rotation direction in the YZ plane. That is, by rotating the first arm 6 in a state where the stylus 9 (91) is in contact with the inner diameter surface of the workpiece W, the region including the right end in the X-axis direction of the inner diameter surface of the workpiece W can be scanned. . Alternatively, the region including the right end in the X-axis direction of the inner diameter surface of the workpiece W can be scanned by moving the second arm 7 forward and backward while the first arm 6 is inclined with respect to the Y-axis.

Needless to say, measurement can be performed by combining these scanning methods and various detectors to measure widths such as diameter values and various surface properties.
In addition, the example in which the second arm 7 slides with respect to the first arm 6 so as to be able to advance and retreat in the linear direction has been shown. However, the present invention is not limited thereto, and the axis of the second arm 7 (parallel to the X axis) The second arm 7 may be rotatable about the center.

Furthermore, the detector main body 8 has been shown to be held rotatably with respect to the second arm 7 around the rotation axis B. However, the detector main body 8 is not limited to this, and the detector main body 8 further includes the second arm 7. On the other hand, it may be held so as to advance and retreat in the X-axis direction.
Further, the Z-axis slider 4 has shown the example in which the X-axis slider 5 is held so as to be able to advance and retreat in the X-axis direction orthogonal to the Z-axis. For example, the Z-axis slider 4 can be tilted in the XZ plane. The forward / backward direction of the slider 5 may be tiltable at an arbitrary angle with respect to the Z axis.

As described above, the width measuring method according to the present invention can be applied to the width, thickness, height, depth, or cylinder of a complicated characteristic part such as a concave part such as a groove on a complicated workpiece or a convex part such as a collar part. The inner diameter value and the outer diameter value (diameter value) can be accurately and easily measured.
Further, according to the surface texture measuring instrument according to the present invention, the relative posture of the detector with respect to the workpiece and the degree of freedom in the relative scanning direction are improved, so that it is possible to perform scanning with high accuracy on any workpiece surface. In addition, since the interference between each structural member of the measuring machine and the workpiece can be avoided, the measurable region is widened, and it can be applied to the use of measuring the surface property of an arbitrary portion of the workpiece.

It is the schematic which shows the roundness measuring device concerning Example 1 of this invention. It is a block diagram of the roundness measurement system concerning Example 1 of the present invention. It is a flowchart which shows the width | variety measuring method concerning Example 1 of this invention. It is a figure which shows the calibration state in the 1st attitude | position and 2nd attitude | position of a detector. It is explanatory drawing of the point data measurement on a workpiece | work. It is explanatory drawing of the line data measurement on a workpiece | work. It is explanatory drawing of the surface data measurement on a workpiece | work. It is another explanatory view of point data measurement on a work. It is another explanatory view of line data measurement on a work. It is another explanatory view of surface data measurement on a work. It is explanatory drawing of a designated point. It is explanatory drawing of width calculation. It is another explanatory view of width calculation. It is other explanatory drawing of width calculation. It is other explanatory drawing of width calculation. It is the schematic which shows the roundness measuring machine concerning 2nd Example of this invention. It is a figure which shows the scanning attitude | position by a roundness measuring device. It is a figure which shows the other scanning attitude | position by a roundness measuring device. It is a flowchart which shows the width | variety measuring method concerning Example 2 of this invention. It is a figure which shows the measurement data concerning Example 2 of this invention. It is a flowchart which shows the width | variety measuring method concerning Example 3 of this invention. It is a figure which shows the calibration process concerning Example 3 of this invention. It is a figure which shows the measurement data concerning Example 3 of this invention. It is the schematic which shows the roundness measuring device concerning the modification of this invention.

Explanation of symbols

1 Roundness measuring machine (surface texture measuring machine)
4 Z-axis slider 5 X-axis slider 6 First arm 7 Second arm 8 Detector main body 9 Contact needle 10 Rotary table 23 Reference ball 100 Computer a1 Specified point b1 Corresponding point W Workpiece

Claims (12)

A width measurement method for obtaining measurement data by scanning the surface of the measurement object with a surface texture measuring instrument equipped with a detector capable of changing a relative measurement posture relative to the measurement object, and measuring the width based on the measurement data Because
A first calibration step of holding the detector in a first orientation and calibrating the detector in the orientation;
A second calibration step of holding the detector in a second orientation and calibrating the detector in the orientation;
A first measurement step of obtaining first measurement data by scanning the first surface of the object to be measured in the first posture of the detector;
A second measurement step of obtaining second measurement data by scanning the second surface of the object to be measured in the second posture of the detector;
A width calculation step of obtaining width data by performing a width calculation process based on the first measurement data and the second measurement data;
A width statistical process for obtaining a width measurement result by performing statistical processing on the width data;
A width measuring method comprising: The width calculation step includes:
A search step of searching for a corresponding point in a specified direction from the specified point in the first measurement data from the second measurement data and calculating a distance from the specified point to the corresponding point as a width;
A control step of performing the search step once or a plurality of times by changing the designated point;
The width measuring method according to claim 1, comprising: The width calculation step includes:
A search step of searching for the corresponding point of the shortest distance from the designated point in the first measurement data, and calculating the distance from the designated point to the corresponding point as a width;
A control step of performing the search step once or a plurality of times by changing the designated point;
The width measuring method according to claim 1, comprising: The width calculation step includes:
A center line calculation step in which inscribed circles inscribed in the first measurement data and the second measurement data are sequentially obtained, and the locus of the center of the inscribed circle is a center line;
A search step of searching for a designated point in the first measurement data and a corresponding point in the second measurement data in a direction orthogonal to the center line, and calculating a distance from the designated point to the corresponding point as a width;
A control step for executing the search step a plurality of times;
The width measuring method according to claim 1, comprising: The width calculation step includes:
A center plane calculation step of sequentially obtaining an inscribed sphere inscribed in the first measurement data and the second measurement data, and calculating a center plane formed from center coordinates of the inscribed sphere;
A search step of searching for a designated point in the first measurement data and a corresponding point in the second measurement data in a direction orthogonal to the center plane, and calculating a distance from the designated point to the corresponding point as a width;
A control step for executing the search step a plurality of times;
The width measuring method according to claim 1, comprising: The width statistical step obtains at least one statistic of a maximum value, a minimum value, and an arithmetic average value when the width data includes a plurality of data. The width measurement method described. A surface texture measuring machine that performs width measurement by the width measuring method according to claim 1. A turntable for rotatably mounting the object to be measured;
A Z-axis slider movable in the Z-axis direction parallel to the rotation axis of the rotary table;
An X-axis slider held by the Z-axis slider and capable of moving back and forth in the X-axis direction orthogonal to the rotational axis;
A first arm held by the X-axis slider and rotatable about a center line A parallel to the X-axis;
A second arm held by the first arm and capable of moving back and forth in a direction perpendicular to the X axis;
A detector that is held by the second arm and measures a surface property of the object to be measured;
A surface texture measuring machine characterized by comprising: 9. The surface texture measuring machine according to claim 8, wherein the detector is held rotatably about a center line B parallel to the advancing / retreating direction of the second arm. A width measuring method for measuring the measured object by the surface texture measuring instrument according to claim 8 or 9, and measuring a width dimension thereof,
A first measurement step of obtaining first measurement data by scanning the first surface of the object to be measured by the detector;
A second measurement step of obtaining second measurement data by scanning the second surface of the object to be measured by the detector;
A width calculation step of obtaining width data by performing a width calculation process based on the first measurement data and the second measurement data;
A width measuring method comprising: In the width calculation step, a maximum value or a minimum value is obtained from each of the first measurement data and the second measurement data, and the diameter value of the object to be measured is set as width data based on the maximum value or the minimum value. The width measuring method according to claim 10. A width measuring method for measuring the measured object by the surface texture measuring instrument according to claim 8 or 9, and measuring a width dimension thereof,
A calibration step of calibrating the detector;
A measurement step of obtaining measurement data by scanning the surface of the object to be measured by the detector;
A width calculation step of obtaining a maximum value or a minimum value from the measurement data and setting the diameter value of the object to be measured as width data based on the maximum value or the minimum value;
A width measuring method comprising:

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