JP2009115527A - Stylus, shape measuring instrument, and part program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To materialize improved efficiency and improved accuracy in measuring a plurality of items on a workpiece. <P>SOLUTION: This stylus 20 is equipped with: one support shaft part 22 provided on a body 18 of a contact-type detector 16 and held thereby centering on its axial direction with its rotation angle changeable; a plurality of shaft parts 24 and 26 for measurement projecting from a side part of the shaft part 22 and differing in directions in which they project from the shaft part 22; and a plurality of contact parts 28 and 30 provided on ends of the respective shaft parts 24 and 26 and differing in end shapes or end sizes by the respective shaft parts 24 and 26. This stylus 20 is characterized in that one contact part 28 (30) answering a measurement purpose is selected from among the plurality of contact parts 28 and 30 through adjustment made for the rotation angle of the shaft part 22 centering on the axial direction of the shaft part 22, and that only the selected contact part 28 (30) is brought into contact with a workpiece 21 and used for acquiring shape data on the workpiece 21. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a stylus, a shape measuring machine, and a part program, and more particularly, to both high efficiency and high accuracy when measuring a plurality of items related to a workpiece.

  Conventionally, shape measurement of a plurality of items such as roundness and roughness of a workpiece has been performed. Conventionally, a plurality of items are measured by separate shape measuring machines. For example, conventionally, even for the same cylindrical workpiece, a roundness measuring machine is used to measure roundness, and a roughness measuring machine is used to measure roughness.

However, it was difficult to prepare a dedicated shape measuring machine for each measurement purpose. This problem became more serious as the purpose of measurement increased.
For this reason, in the field of measuring the shape of a plurality of items, there is still room for improvement in measuring efficiency. Conventionally, it is conceivable to perform a plurality of items with a single shape measuring machine (see, for example, Patent Document 1).

Japanese Examined Patent Publication No. 6-48186 (page 5-6, Fig. 2)

However, although the technique described in Patent Document 1 can cope with the shape measurement of a plurality of measurement surfaces having different surface directions, the analysis of a plurality of items such as roundness and roughness is improved. A measurement result with sufficient accuracy to be performed accurately could not be obtained.
Conventionally, in order to obtain a satisfactory measurement result for each measurement purpose, it may be possible to change the stylus for each measurement purpose. However, if the stylus is changed for each measurement purpose, the measurement efficiency is significantly reduced. Therefore, it has not been adopted as the solution of the present invention.

Thus, in the field of measuring the shape of multiple items, it was urgent to develop a technology that can obtain both measurement efficiency and measurement accuracy at a very high level, but this can be solved conventionally. There was no appropriate technology.
The present invention has been made in view of the prior art, and an object thereof is to realize high efficiency and high accuracy when measuring a plurality of items with respect to a workpiece.

  As a result of intensive studies on the above problems by the present inventors, a single stylus in which a plurality of contact portions having different tip shapes or tip dimensions are provided on one support shaft portion in accordance with the measurement purpose is formed. By rotating one of the multiple contact parts, one contact part suitable for the purpose of measurement is selected and used for measuring the shape of the work. The present inventors have found that accuracy can be reliably obtained and have completed the present invention.

(1) Stylus That is, in order to achieve the above object, the stylus according to the present invention moves the contact position between the stylus tip and the surface to be measured while the stylus tip is in contact with the surface to be measured of the workpiece. However, a stylus that is used for a detector that obtains the shape data of the surface to be measured and is used for a plurality of different measurement purposes,
A support shaft portion, a plurality of measurement shaft portions, and a plurality of contact portions are provided.
Here, the support shaft portion is held by the main body of the detector, and the rotation angle can be freely changed around the axial direction.
The plurality of measurement shaft portions protrude from side portions of the support shaft portion, and are different in directions protruding from the support shaft portion.
The plurality of contact portions are provided at the distal ends of the respective measurement shaft portions, and the distal end shape or the distal end dimension is different for each measurement shaft portion.
The stylus according to the present invention has one contact portion corresponding to the measurement purpose from the plurality of contact portions by changing the rotation angle of the support shaft portion around the axial direction of the support shaft portion. Is selected, and only the selected contact portion of the plurality of contact portions is brought into contact with the surface to be measured, and is used for acquiring the shape data of the surface to be measured.

  The axial direction of the support shaft here refers to the center axis of the support shaft when the center axis of the support shaft matches the center axis of the detector body, and the center axis of the support shaft is detected. In the case of a configuration located at a position deviated from the central axis of the vessel body, it refers to an axial direction parallel to the central axis of the support shaft.

In the stylus according to the present invention, the contact portion is a ball-shaped contact portion for roundness suitable for measuring roundness for the measurement purpose, and for measuring roughness for the measurement purpose. It is preferred to include a suitable acicular roughness contact.
In the stylus according to the present invention, when measuring the roundness of the workpiece, the roundness contact portion is selected from the plurality of contact portions, and only the roundness contact portion is the The rotation angle of the support shaft is adjusted so as to be in contact with the surface to be measured and used for measuring the roundness of the workpiece.
In the stylus according to the present invention, when measuring the roughness of the workpiece, the roughness contact portion is selected from the plurality of contact portions, and only the roughness contact portion is the surface to be measured. It is preferable that the rotation angle of the support shaft portion is adjusted so that the support shaft portion is used for measuring the roughness of the workpiece.

(2) Shape measuring machine In order to achieve the above object, the shape measuring machine according to the present invention includes the stylus and the detector, detector rotating means, and rotation control means. .
Here, the detector rotating means rotatably holds the detector so that the rotation angle of the support shaft portion can be changed around the axial direction of the support shaft portion.
Further, the rotation control means selects a desired contact portion according to the measurement purpose from the plurality of contact portions, and only the desired contact portion is brought into contact with the surface to be measured. The rotation of the detector by the detector rotating means is controlled so as to be used for acquisition of shape data.

In the shape measuring machine according to the present invention, it is preferable to include a correction value storage unit, a correction unit, and an analysis unit.
Here, the shape data from the detector is trajectory information of the center of the contact portion moving on the surface to be measured of the workpiece, and contour information on the surface to be measured is obtained from the trajectory information of the center of the contact portion. In order to obtain the correction value, a correction value based on the dimension between the tip and the center of the contact portion is obtained in advance for each contact portion.
Further, the correction value storage means stores the correction value for each contact portion.
The correction means corrects the shape data from the detector with the correction value corresponding to the contact portion used when obtaining the shape data, and obtains corrected data.
The analysis unit performs data analysis according to the measurement purpose when the contact portion is selected based on the corrected data obtained by the correction unit.

  As the shape measuring instrument of the present invention, for example, the one described in Japanese Patent Application Laid-Open No. 2007-155696 is particularly preferable.

(3) Part program The part program according to the present invention for achieving the above object is a part program for causing a computer to execute a plurality of measurement steps by the shape measuring machine according to the present invention. ,
The measurement process includes a contact part selection process, a setting process, and a data acquisition process.
Here, the contact part selection step adjusts the rotation angle of the detector so that one contact part corresponding to the measurement purpose is selected from the plurality of contact parts.
Moreover, the said setting process makes only the contact part selected by the said contact part selection process contact the to-be-measured surface of the said workpiece | work.
The data acquisition step is provided at a subsequent stage of the setting step, and in a state where only the contact portion selected by the contact portion selection step is in contact with the surface to be measured of the workpiece, the contact portion and the surface to be measured The shape data of the surface to be measured is obtained while moving the contact position.
And in the part program concerning this invention, the said several measurement process from which the said measurement objective differs is performed.

In the part program according to the present invention, it is preferable that the plurality of measurement steps include a roundness measurement step and a roughness measurement step.
Here, in the roundness measurement step, a ball-shaped roundness contact portion suitable for measuring the roundness of the workpiece is selected from the plurality of contact portions of the stylus.
In the roughness measuring step, a needle-like contact portion for roundness suitable for measuring the roughness of the workpiece is selected from the plurality of contact portions of the stylus.

In the part program according to the present invention, it is preferable that the computer further causes a correction process and an analysis process to be executed.
Here, the shape data from the detector is trajectory information of the center of the contact portion moving on the surface to be measured, and in order to obtain contour information on the surface to be measured from the trajectory information of the center of the contact portion, A correction value based on the dimension between the tip and the center of the contact portion is obtained in advance for each contact portion.
In the correction step, the shape data from the detector is corrected with the correction value corresponding to the contact portion used when the shape data was obtained, and corrected data is obtained.
The analysis step performs data analysis according to the measurement purpose when the contact portion is selected based on the corrected data from the correction step.

(1) Stylus According to the stylus of the present invention, a plurality of contact portions having different tip shapes or tip dimensions are provided for one support shaft portion according to the measurement purpose, and the support shaft portion is rotated. Thus, a tip shape or tip size contact portion suitable for the measurement purpose is selected from a plurality of contact portions and used for workpiece shape measurement. As a result, according to the stylus according to the present invention, one stylus Thus, since the measurement of each item can be performed satisfactorily, it is possible to reliably realize both high efficiency and high accuracy when measuring a plurality of items.
The stylus according to the present invention includes a ball-shaped roundness contact portion suitable for measuring roundness, and a needle-like roughness contact portion suitable for measuring roughness. Thus, it is possible to reliably realize both high efficiency and high accuracy when measuring roundness and roughness with one stylus.

(2) Shape measuring machine According to the shape measuring machine according to the present invention, the rotational angle position of the stylus according to the present invention can be changed by the detector rotating means. It is possible to select a contact portion having a tip shape or tip size according to the shape and use it for measuring the shape of the workpiece.
As a result, according to the profile measuring machine according to the present invention, it is possible to reliably achieve both high efficiency and high accuracy when measuring a plurality of items with a single unit.

(3) Part program According to the part program of the present invention, the computer is caused to execute the plurality of measurement steps. As a result, according to the part program according to the present invention, it is possible to achieve both high efficiency and high accuracy when measuring a plurality of items with a single shape measuring machine.
In the part program according to the present invention, by further causing the computer to execute the correction process and the analysis process, it is possible to further improve the efficiency and accuracy when measuring a plurality of items. it can.

Hereinafter, a preferred embodiment of the present invention will be described with reference to the drawings.
FIG. 1 shows a schematic configuration of a shape measuring machine according to an embodiment of the present invention.
In the present embodiment, an example will be described in which measurement of a plurality of items from preliminary measurement required for centering and leveling of a workpiece to roundness and roughness is completely automated by a part program.
A CNC roundness measuring machine (shape measuring machine) 10 shown in FIG. 1 includes a measuring machine main body 12 and a computer 14. The measuring machine main body 12 is connected to a computer 14.
The measuring machine main body 12 includes a roughness sensor (contact type detector) 16.
Here, the roughness sensor 16 includes a detector main body 18 and a roughness measuring two-pronged stylus (stylus) 20 for a CNC roundness measuring machine.

In the present embodiment, since the roundness and roughness of the workpiece are measured with one stylus, a bifurcated stylus for roundness and roughness is used.
For this reason, in the present embodiment, the stylus 20 includes a single support shaft portion 22, a roundness shaft portion 24, a roughness shaft portion 26, a roundness contact portion 28, and a roughness contact portion. Contact portion 30.
Here, the one support shaft portion 22 is held by the detector main body 18, and together with the detector main body 18, the rotation angle can be freely changed around the central axis of the detector 18.
The roundness shaft portion 24 and the roughness shaft portion 26 protrude from the side portion of the one support shaft portion 22, and protrude from the support shaft portion 22 in a plane orthogonal to the axial direction of the support shaft portion. The direction shall be different.
The roundness contact portion 28 is provided at the tip of the roundness shaft portion 24 and has a ball shape suitable for measuring the roundness of the workpiece 21. The roughness contact portion 30 is provided at the tip of the roughness shaft portion 26 and has a needle shape suitable for measuring the roughness of the workpiece 21.

The roundness contact portion of the present invention has a tip shape or tip size suitable for measuring roundness, and in this embodiment, the roundness contact portion 28 has the following ball shape. Yes.
Shape: Ball shape Radius: φ1.6mm

Further, the roughness contact portion 30 of the present invention has a tip shape or tip size suitable for measuring roughness. In this embodiment, the roughness contact portion 30 has the following needle shape. Yes.
Shape: cone (needle)
Tip radius of curvature (R): 2 μm

In the present embodiment, by adjusting the rotation angle of the support shaft portion 22, one contact portion corresponding to the measurement purpose is selected from the contact portions 28 and 30.
That is, when measuring the roundness of the workpiece 21, the support shaft portion 22 is selected so that the roundness contact portion 28 is selected from the contact portions 28 and 30 and used for measuring the roundness of the workpiece 21. The rotational angle position of is controlled.
Further, when measuring the roughness of the workpiece 21, the rotation angle of the support shaft portion 22 is selected so that the roughness contact portion 30 is selected from the contact portions 28 and 30 and used for the roughness measurement of the workpiece 21. The position is controlled.

In the present embodiment, a detector holder 40, a detector rotating means 42, and a rotation control means 44 are provided to switch the contact part used for measurement purposes from the contact parts 28 and 30.
Here, the detector holder 40 rotatably holds the roughness sensor 16 so that the rotation angle of the stylus 20 can be changed around the central axis of the roughness sensor 16.
Further, the detector rotating means 42 rotates the roughness sensor 16 around the central axis of the roughness sensor 16 so that the rotation angle of the stylus 20 can be changed. In this embodiment, in order to improve the measurement efficiency, the existing detector rotating means is used in the CNC roundness measuring machine 10 as the detector rotating means of the present invention. The detector rotating means 42 allows the rotation angle of the roughness sensor 16 to be changed while the detector holder 40 is in the vertical posture.
When the roundness of the workpiece 21 is measured, the rotation control unit 44 is configured so that the rotation angle position of the roundness shaft portion 24 becomes a predetermined rotation angle position for measuring the roundness of the workpiece 21. The rotation operation of the detector rotating means 42 is controlled. Further, when measuring the roughness of the workpiece 21, the rotation control unit 44 detects so that the rotation angle position of the roughness shaft portion 26 becomes a predetermined rotation angle position for measuring the roughness of the workpiece 21. The rotating operation of the device rotating means 42 is controlled.

  In the present embodiment, the column 50 is erected on the main body base 52 and holds the slider 54 so as to be movable in the vertical direction. An arm 56 is held by the slider 54 so as to be movable in the horizontal direction, and a detector holder 40 is provided on the arm 56.

Moreover, in this embodiment, the rotary table 60 is provided as a relative motion means of this invention. The rotation table 60 is an index table and outputs rotation angle information to the computer 14 at a predetermined pitch. The rotation angle information from the rotary table 60 is recorded in the computer 14 together with the unevenness information (shape data) of the surface to be measured of the workpiece 21 from the roughness sensor 16 for analysis of roundness, roughness, and the like. Used.
In the present embodiment, when the adjustment amount is instructed from the computer 14, the rotation table 60 automatically adjusts the rotation table 60 based on the adjustment amount, and automatically performs the centering / leveling work of the workpiece 21 before the measurement. Shall.

In order to fully automate roundness measurement and roughness measurement from the center / leveling of the workpiece 21, the computer 14 measures a plurality of items in accordance with a part program procedure prepared in advance. The part program 72 is used to perform movement and measurement operations of each axis of the CNC roundness measuring machine 10 by numerical control by the computer 14.
For this purpose, in the present embodiment, the computer 14 includes part program storage means 70. The program storage means 70 stores a part program 72.
The part program 72 is for causing the computer 14 to execute the centering / leveling process of the present invention, the roundness measuring process of the present invention, and the roughness measuring process of the present invention.
In addition, the computer 14 includes analysis means 74 for performing the analysis process of the present invention.
Based on the shape data from the roughness sensor 16, the analysis means 74 performs data analysis according to the measurement purpose when the contact portion is selected. That is, when the roundness contact portion 28 is selected, the roundness of the workpiece 21 is analyzed based on the shape data from the roughness sensor 16. When the roughness contact portion 30 is selected, the surface roughness of the workpiece 21 is analyzed based on the shape data from the roughness sensor 16.

The CNC roundness measuring device 10 according to this embodiment is configured as described above, and the operation thereof will be described below.
Conventionally, when measuring multiple items such as roundness and roughness for the same workpiece, each dedicated stylus was manually replaced or measured with a separate shape measuring machine, so the shape measuring machine could be fully automated. Whereas it was difficult, in the present embodiment, full automation is realized. That is, in the present embodiment, a plurality of contact portions with respect to one support shaft portion 22, that is, a ball-shaped contact portion 28 for roundness suitable for measuring roundness, to measure roughness. A suitable needle-shaped roughness contact portion 30 is provided to constitute one stylus 20. Then, by adjusting the rotation angle of one stylus 20, when measuring the roundness of the workpiece 21, the ball-shaped contact portion 28 for roundness is selected, and when measuring the roughness of the workpiece 21. The needle-shaped roughness contact portion 30 is selected.

FIG. 2 shows a schematic diagram of a stylus according to an embodiment of the present invention.
FIG. 4A is a view of the stylus viewed from an oblique direction, FIG. 4B is a view of the stylus viewed from above when the roundness contact portion is selected, and FIG. It is the figure which looked at the stylus from the upper part at the time of selection of a contact part.
That is, as shown in FIG. 2B, when measuring the roundness of the workpiece 21, the roundness contact portion 28 is selected from the contact portions 28 and 30, and the roundness of the workpiece 21 is measured. As used for the measurement, the rotational angle position of the support shaft 22 is controlled. For example, in order to select the roundness contact portion 28, the roundness contact portion 28 is arranged on a line 78 connecting the center 76 of the workpiece 21 and the center of the support shaft portion 22 in the horizontal direction (the paper surface direction in the figure). The rotational angle position of the support shaft portion 22 is controlled with the central axis of the support shaft portion 22 as the center of rotation.
Further, as shown in FIG. 2C, when measuring the roughness of the workpiece 21, the roughness contact portion 30 is selected from the contact portions 28, 30 and used for measuring the roughness of the workpiece 21. Thus, the rotational angle position of the support shaft portion 22 is controlled. For example, in order to select the roughness contact portion 30, the roughness contact portion 30 is positioned on the line 78 connecting the center 76 of the workpiece 21 and the center of the support shaft portion 22 in the horizontal direction (roughness). The rotation angle position of the support shaft portion 22 is controlled with the central axis of the support shaft portion 22 as the center of rotation so that the axial direction of the shaft portion 26 coincides.

  As a result, in this embodiment, when measuring roundness and roughness, without changing the stylus as in the conventional method, and without using a separate shape measuring instrument as in the conventional method. By simply changing the rotational angle position of one stylus 20, a single CNC roundness measuring device 10 can measure a plurality of items such as roundness and roughness with high efficiency and high accuracy, respectively. it can.

For example, in the present embodiment, combined measurement of roundness and roughness of the same workpiece 21 can be performed fully automatically and in a short time by the part program 72 including the center / leveling operation. .
Further, in this embodiment, since a contact portion suitable for the purpose of measurement is selected and used for workpiece measurement, it was difficult to measure a plurality of items using the same contact portion. Consistency of measurement results with the conventional method can be ensured.
Thereby, in this embodiment, since the roundness and roughness are improved compared to the conventional method, that is, the stylus is replaced or measured with a separate shape measuring machine, the operability and convenience are further improved. Measurement time can be shortened.

Hereinafter, the operation will be described more specifically.
In the present embodiment, the following measurement steps having different measurement purposes are executed according to the part program.
(1) Centering / leveling FIG. 3 shows the processing procedure of the centering / leveling process.
In the centering / leveling step, the contact portion selection step as shown in FIG. 10A, the first setting step and the data acquisition step as shown in FIG. A second setting step and a data acquisition step as shown, and an adjustment step as shown in FIG.
That is, in the centering / leveling step, it is necessary to first perform preliminary measurement and detect the amount of misalignment between the center and horizontal of the workpiece. In the preliminary measurement, by adjusting the rotational angle position as shown in FIG. 5A, a contact portion suitable for detecting the center / horizontal deviation amount of the workpiece 21, for example, a ball-like perfect circle The degree contact portion 28 is automatically selected.
Next, as shown in FIG. 5B, the roundness contact portion 28 is set at the part to be measured of the workpiece 21. The detector is automatically set at the measurement site (height A) of the workpiece 21. Next, the rotary table 60 automatically rotates and takes in data.
Here, the computer performs preliminary measurement at the height A of the workpiece 21 and obtains the center coordinates of the workpiece 21 at the height A.
Next, the computer performs preliminary measurement at the height B of the workpiece 21 and obtains the center coordinates of the workpiece 21 at the height B, as shown in FIG.
From the center coordinates of the workpiece 21 at the height A and the center coordinates of the workpiece 21 at the height B, the computer obtains the center / leveling amount (center deviation correction amount, inclination correction amount) of the workpiece 21.
In this way, the computer obtains the center / horizontal misalignment amount (center misalignment correction amount, tilt correction amount) of the workpiece 21, and rotates the adjustment amount of the rotary table 60 based on the center misalignment correction amount and tilt correction amount. Instruct the table and instruct the rotary table for automatic adjustment.
As a result, the rotary table 60 automatically adjusts the rotary table 60 based on the workpiece centering / leveling amount (center misalignment correction amount, tilt correction amount), and automatically performs the centering / leveling operation of the workpiece 21. (See (D) in the figure).
After the workpiece 21 is centered and leveled automatically by the rotary table 60 as described above, the combined measurement of the roundness and roughness of the centered and leveled workpiece 21 is performed as follows. Done automatically.

(2) Roundness Measurement FIG. 4 shows the processing procedure of the roundness measurement process.
That is, the roundness measurement process includes the contact part selection process as shown in FIG. 5A, the set process as shown in FIG. 5B, and the data as shown in FIG. An acquisition step.
Here, in the contact portion selection step, as shown in FIG. 3A, a roundness contact portion 28 suitable for analyzing the roundness of the workpiece 21 is selected from the plurality of contact portions 28 and 30. The rotational angle position of the stylus 16 is automatically adjusted to be selected.
In the setting step, only the roundness contact portion 28 is automatically brought into contact with the surface to be measured of the workpiece 21 as shown in FIG.
In the data acquisition step, as shown in FIG. 5C, the rotary table 60 is rotated with the roundness contact portion 28 in contact with the surface to be measured of the work 21, and the roundness contact portion. The shape data of the surface to be measured of the work 21 is obtained while moving the contact position between the surface 28 and the surface to be measured of the work 21.
As described above, when measuring the roundness, a ball-shaped roundness contact portion 28 suitable for measuring the roundness of the workpiece 21 is selected and automatically set to the measurement site of the workpiece 21. Next, in a state where the roundness contact portion 28 is in contact with the part to be measured of the workpiece 21, the rotary table 60 is automatically rotated to capture data. Based on the fetched data, the roundness of the workpiece 21 is automatically analyzed by the analyzing means.

(3) Roughness Measurement FIG. 5 shows the processing procedure of the roughness measurement process.
That is, the roughness measurement process includes a contact part selection process as shown in FIG. 5A, a setting process as shown in FIG. 5B, and data acquisition as shown in FIG. A process.
Here, in the contact portion selection step, as shown in FIG. 5A, a roughness contact portion 30 suitable for analyzing the roughness of the workpiece 21 is selected from the plurality of contact portions 28 and 30. Thus, the rotational angle position of the stylus 16 is adjusted.
In the setting step, only the roughness contact portion 30 is brought into contact with the surface to be measured of the workpiece 21 as shown in FIG.
In the data acquisition step, as shown in FIG. 3C, the rotary table 60 is rotated with the roughness contact portion 30 in contact with the surface to be measured of the workpiece 21, and the roughness contact portion 30 and The shape data of the surface to be measured of the workpiece 21 is obtained while moving the contact position of the workpiece 21 with the surface to be measured.
As described above, in the roughness measurement step, the needle-like roughness contact portion 30 suitable for measuring the roughness of the workpiece 21 is automatically selected and automatically set to the measurement site of the workpiece 21. Next, in a state where the contact portion for roughness 30 is in contact with the part to be measured of the workpiece 21, the rotary table 60 is automatically rotated to capture data. Based on the fetched data, the roughness of the workpiece 21 is analyzed by the analyzing means.

As described above, the CNC roundness measuring machine 10 according to the present embodiment is excellent in the following points.
(1) When performing the centering / leveling work, the work can be completed at the same speed as the conventional measuring method by using a ball-shaped contact portion suitable for the preliminary measurement.
(2) When measuring roundness, a measurement result consistent with the conventional method can be obtained by using a ball-shaped contact portion suitable for roundness measurement.
(3) At the time of roughness measurement, a measurement result having consistency with the conventional method can be obtained by using a needle-shaped contact portion suitable for roughness measurement.
(4) By using the above functions (1) to (3) together, a part program can include complex measurements such as roughness and roundness for the same workpiece, including the centering and leveling work. Can be done fully automatically and in a short time. As a result, in this embodiment, it is possible to realize both high efficiency and high accuracy of measurement, which is extremely difficult with the conventional method.

By the way, full automation in the present embodiment can be obtained for the first time by adopting the stylus of the present invention. In the conventional stylus, both high efficiency and high accuracy when measuring a plurality of items are achieved. Therefore, full automation as in this embodiment is extremely difficult.
In other words, with regard to roughness measurement using a roundness measuring machine, it has been possible to use a roughness sensor, but with a single roughness stylus, many items such as surface roughness and roundness can be obtained. The measurement has the following disadvantages.

(1) In the preliminary measurement required for roundness measurement and centering / leveling work, instead of the ball-shaped contact part normally used for roundness measuring machines, the sharp contact point part for roughness When the workpiece has a cutter mark on the surface to be measured, the contact portion follows the unevenness of the cutter mark, and the consistency of the measurement result cannot be maintained.
(2) For preliminary measurement required for centering and leveling work and for roundness measurement, the contact surface is tracked on a surface to be measured over a long distance that is uncomparable with normal roughness measurement. In addition, if the speed of the follow-up increases, wear and chipping at the tip of the contact portion may be deteriorated, so that caution monitoring is always required.
(3) In order to prevent the above problems (1) and (2), a stylus for roughness and a stylus for preliminary measurement and roundness measurement necessary for centering and leveling work are prepared separately for measurement purposes. It is conceivable to use the stylus properly depending on the stylus. However, manual replacement is required to replace the stylus, and correction work after replacement of the stylus is also required, so that the measurement efficiency does not increase. In addition, the conventional system has not realized an automatic exchange system.

On the other hand, in the present embodiment, the stylus is forked for roundness and roughness, and the detector rotating means already installed in the hardware and software of the CNC roundness measuring machine is used. Thus, the rotation angle of the stylus can be freely changed.
As a result, in the present embodiment, even when one stylus is used, by properly using a contact portion suitable for the purpose of measurement, the conventional method, for example, when measuring a plurality of items with one roughness stylus, Disadvantages can be eliminated.

Further improvement in measurement efficiency (1) Fully automated correction In the present embodiment, the shape data from the roughness sensor 16 is the locus information of the center of the contact portion that moves on the surface to be measured of the workpiece 21, In order to obtain the contour information on the surface to be measured of the workpiece 21 from the trajectory information of the contact portion center, it is necessary to correct the trajectory information of the contact portion center with a correction value based on the dimension between the tip and the center of the contact portion.
Here, in the present embodiment, the above-described correction is also completely automated by the part program 72 in order to further increase the measurement efficiency.
Therefore, in this embodiment, as shown in FIG. 6, the computer 14 further includes a correction value storage unit 80 and a correction unit 82 for performing the correction process of the present invention.
Here, the correction value storage means 80 stores a correction value based on the dimension between the tip and the center of the contact portion for each of the contact portions 28 and 30. In the present embodiment, the radius of the roundness contact portion 28 is stored as the correction value for the roundness contact portion 28, and the roughness is used as the correction value for the roughness contact portion 30. The distance between the tip and the center of the contact portion 30 is stored.
The correction means 82 corrects the shape data from the measuring machine main body 12 (shape data from the detector) with a correction value corresponding to the contact portion when the shape data is obtained, and obtains corrected data. That is, in the present embodiment, the shape data obtained using the roundness contact portion 28 is corrected with the correction value for the roundness contact portion 28, and corrected data for roundness analysis is obtained. Get. In the present embodiment, the shape data obtained by using the roughness contact portion 30 is corrected with the correction value for the roughness contact portion 30 to obtain corrected data for roughness analysis.
In the present embodiment, the part program 72 controls the operation of the correction means 82 so that the computer 14 executes the correction process of the present invention.

(2) Fully automated analysis In this embodiment, the analysis of items such as roundness and roughness based on the corrected data as described above is also performed by the part program 72 in order to further improve the measurement efficiency. It is fully automated.
For this purpose, the present embodiment further includes an analysis means 74 for performing the analysis process of the present invention.
The analysis unit 74 analyzes the roundness and roughness based on the corrected data obtained by the correction unit 82. That is, in the present embodiment, the roundness is analyzed based on the corrected data for roundness analysis obtained by the correction unit 82. In the present embodiment, the roughness is analyzed based on the corrected data for roughness analysis obtained by the correction means 82.
In the present embodiment, the part program 72 controls the operation of the analysis means 74 so that the computer 14 executes the analysis process of the present invention.

Modifications The present invention is not limited to the above-described configuration, and various modifications can be made within the scope of the gist of the invention.
(1) Stylus In the above configuration, the example in which the stylus is split into two has been described. However, the present invention is not limited to this, and the stylus may be set to three or more according to the measurement purpose. It is also preferable to achieve more measurement purposes with a single stylus by devising the tip shape or tip dimension.

(2) Measurement purpose In the above configuration, the example in which the roundness and the surface roughness are measured has been described. However, the present invention is not limited to this, and other measurement purposes can be selected.

It is explanatory drawing of schematic structure of the shape measuring machine concerning one Embodiment of this invention. It is explanatory drawing of schematic structure of the stylus concerning one Embodiment of this invention. It is explanatory drawing of the setup work before the measurement by the shape measuring machine concerning one Embodiment of this invention. It is explanatory drawing of the roundness measurement process by the shape measuring machine concerning one Embodiment of this invention. It is explanatory drawing of the roughness measurement process by the shape measuring machine concerning one Embodiment of this invention. It is explanatory drawing of the correction | amendment means and the analysis means of the shape measuring machine concerning one Embodiment of this invention.

Explanation of symbols

10 CNC roundness measuring machine (shape measuring machine)
12 Measuring Machine Body 14 Computer 16 Roughness Sensor (Detector)
18 Detector body 20 Roughness measuring two-pronged stylus (stylus) for CNC roundness measuring machine
22 Support Shaft 24 Roundness Shaft (Measurement Shaft)
26 Contact section for roughness (measurement shaft)
28 Contact part for roundness (contact part)
30 Roughness contact area (contact area)
70 Part program storage means 72 Part program

Claims (7)

Used in a detector that obtains the shape data of the surface to be measured while moving the contact position between the tip of the stylus and the surface to be measured while the stylus tip is in contact with the surface to be measured of the workpiece. A stylus used for measurement purposes,
A support shaft that is held by the detector body and is capable of changing the rotation angle around the axial direction;
A plurality of measurement shafts that protrude from the side of the support shaft and have different directions protruding from the support shaft,
A plurality of contact portions provided at the distal ends of the respective measurement shaft portions, and having different tip shapes or tip dimensions for the respective measurement shaft portions;
The rotation angle of the support shaft portion is adjusted around the axial direction of the support shaft portion, so that one contact portion corresponding to the measurement purpose is selected from the plurality of contact portions, and the selection is performed. A stylus characterized in that only the contacted portion is brought into contact with the surface to be measured and used to acquire shape data of the surface to be measured. The stylus of claim 1.
The contact portion includes a ball-shaped roundness contact portion suitable for measuring roundness as the measurement purpose, and a needle-shaped roughness contact suitable for measuring roughness as the measurement purpose. Part
When measuring the roundness of the workpiece, the roundness contact portion is selected from the plurality of contact portions, and only the roundness contact portion is brought into contact with the surface to be measured. The rotation angle of the support shaft is adjusted so that it can be used to measure the roundness of
When measuring the roughness of the workpiece, the contact portion for roughness is selected from the plurality of contact portions, and only the contact portion for roughness is brought into contact with the surface to be measured. The stylus is characterized in that the rotation angle of the support shaft portion is adjusted so as to be used for the measurement. A stylus and a detector according to claim 1 or 2;
Detector rotation means for rotatably holding the detector so that the rotation angle of the support shaft portion can be changed;
A desired contact portion corresponding to a measurement purpose is selected from the plurality of contact portions, and only the desired contact portion is brought into contact with the surface to be measured and used for obtaining shape data of the surface to be measured. Rotation control means for controlling rotation of the detector by the detector rotation means;
A shape measuring machine characterized by comprising: In the shape measuring machine according to claim 3,
When the shape data from the detector is the locus information of the center of the contact portion moving on the surface to be measured of the workpiece, the contour information on the surface to be measured is obtained from the locus information of the center of the contact portion. The correction value based on the dimension between the tip and the center of the contact portion is obtained in advance for each contact portion,
Correction value storage means for storing the correction value for each contact portion;
Correction means for correcting the shape data from the detector with the correction value corresponding to the contact portion used when obtaining the shape data, and obtaining corrected data;
Based on the corrected data obtained by the correction means, analysis means for performing data analysis according to the measurement purpose when the contact portion is selected;
A shape measuring machine characterized by comprising: A part program for causing a computer to execute a plurality of measurement steps by the shape measuring machine according to claim 3 or 4,
The measurement step includes a contact part selection step of adjusting a rotation angle of the detector so that one contact part corresponding to a measurement purpose is selected from the plurality of contact parts.
Only the contact portion selected in the contact portion selection step is brought into contact with the surface to be measured of the workpiece; and
The contact position between the contact portion and the surface to be measured is moved while only the contact portion selected in the contact portion selection step is in contact with the surface to be measured of the workpiece. However, a data acquisition step for acquiring the shape data of the surface to be measured;
A part program characterized in that a plurality of the measurement steps having different measurement purposes are executed. In the part program according to claim 5,
The plurality of measurement steps include a roundness measurement step and a roughness measurement step,
In the roundness measuring step, a ball-shaped contact portion for roundness suitable for measuring the roundness of the workpiece is selected from the plurality of contact portions of the stylus,
In the roughness measuring step, a needle-like roundness contact portion suitable for measuring the roughness of the workpiece is selected from the plurality of contact portions of the stylus. In the part program according to claim 5 or 6,
The computer is further caused to execute a correction process and an analysis process,
When the shape data from the detector is the locus information of the center of the contact portion moving on the surface to be measured, in order to obtain the contour information on the surface to be measured from the locus information of the center of the contact portion, A correction value based on the dimension between the tip and the center of the contact portion is obtained in advance for each of the contact portions,
In the correction step, the shape data from the detector is corrected with the correction value corresponding to the contact portion used when obtaining the shape data, and corrected data is obtained,
The part program characterized in that the analysis step performs data analysis according to the measurement purpose when the contact portion is selected based on the corrected data from the correction step.

Images