JP2001041738A - Circularity measurement method and device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To find an error in the circularity of a cylindrical shape so as to enable evaluation by comparing a design value of a cylindrical object to be measured having a non-circle shape or a partial different area with an actual measurement value of the object. SOLUTION: A measurement value of a circular column shaped object to be measured constituted of a non-circle area being a whole part and another unique shaped area is input, and based on original point coordinates 302 of design value a file of a design figure 301 is formed. Then, the cylindrical column shaped object to be measured formed based on the design value is measured in order to form a recorded figure 351, and matching is carried out so that the total of deviations in respective rotational angles with respect to the design figure 301 may be the minimum. Thereafter, the sum of a deviation 366 to a figure 363 obtained by moving the design figure 301 to have a minus side minimum deviation and a deviation 367 to a figure 364 obtained by moving the design figure 301 to have a plus side maximum deviation is obtained so that evaluation of circularity is conducted. The original coordinates 302 corrects a deviation from the center of rotation 352 of a circularity measurement device and is used for matching in the design value.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a method for rotating a workpiece (hereinafter referred to as a "workpiece") or a detector to determine the roundness or cylindrical shape of a workpiece (hereinafter simply referred to as "roundness"). For the roundness measuring machine to be measured, especially when correcting the inclination and evaluating the shape of a workpiece that has a unique area such as a notch in a part of a cylindrical shape, or a piston manufactured for the purpose of a non-circular shape from the design time The present invention relates to a method and an apparatus for measuring a shape suitable for a computer.

[0002]

2. Description of the Related Art A radius method roundness measuring machine (hereinafter simply referred to as "roundness measuring device") reproduces a reference axis close to a geometric circle by using a roundness measuring machine, and focuses on the reference axis. The detector is relatively rotated around the object to be measured, and the displacement signal of the detector is compared with a reference circle obtained from a reference axis for evaluation.

[0003] Roundness measuring machines can be broadly classified into table rotating roundness measuring machines and detector rotating roundness measuring machines. (FIG. 1) As shown in FIG. 1 (A), a table rotation type roundness measuring machine includes a rotation axis (Z0), which is an ideal reference axis with high accuracy obtained by rotating a rotary table. The axis of the workpiece is calculated from the displacement signal of the detector obtained by rotating the rotary table by the detector abutting on the cylindrical surface of the workpiece placed on the rotary table. As shown in FIG. 1 (B), the detector rotation type roundness measuring device has a rotation axis (Z0) which is an ideal reference axis with high accuracy obtained by rotation of a rotation bearing.
Then, the axis of the workpiece is calculated from the displacement signal of the detector obtained from the rotation of the rotary bearing by the detector mounted on the rotary bearing on the cylindrical surface of the workpiece placed on the table.

The work axis calculation means is a work axis calculation means for which the circumscribed circle center method, the inscribed circle center method, the minimum area center method, and the least square center method are known. (Fig. 2)

In the circumscribed circle center method, as shown in FIG. 2A, a minimum circumscribed circle surrounding a circular figure (W0) obtained when a displacement signal of a detector (hereinafter referred to as a "detection signal") is recorded on polar coordinates. In a roundness evaluation method represented by the two radius differences between the circle (A1) and the circle (A2) concentric with the circle (W0), the center (AO) of the two circles (A1, A2) is The center (AO) determined by the circumcircle center method.

In the inscribed circle center method, as shown in FIG.
Roundness evaluation represented by two radius differences between a maximum inscribed circle (B1) surrounding a circular figure (W0) obtained when a detection signal is recorded on polar coordinates and a circle (B2) concentrically circumscribing a circular figure. In the method, the center (BO) of the two existing circles (B1, B2) is the center (BO) obtained by the inscribed circle center method.

In the minimum area centering method, as shown in FIG. 1C, a circle (C1) inscribing a circular figure (W0) obtained when a detection signal is recorded on polar coordinates and a circle (C1) circumscribing a circle are concentric. In the roundness evaluation method represented by the radius at which the difference between the two radii becomes minimum, the center (CO) of the two already-existing circles (C1, C2) is the center (CO) obtained by the minimum area center method.

In the least squares method, as shown in FIG. 1D, a perfect circle is arranged on a circular figure (W0) obtained when a detection signal is recorded on polar coordinates, and a radius difference between the perfect circle and the circular figure is obtained. In other words, the circle having the smallest square of the error is defined as the reference circle (D1), and the true circle represented by the two radius differences between the circumscribed circle (D2) concentric with the existing reference circle and the inscribed circle (D3) concentric with the existing reference circle. In the roundness evaluation method, the reference circle (D1) and the two existing circles (D2, D
The center (DO) of 3) is the center (DO) obtained by the least square center method.

FIG. 3 is a diagram showing a true circle obtained by calculating a circular figure obtained by recording a detection signal of a work having a notch which is a unique area in a part of a cylindrical shape on polar coordinates by using the inscribed circle center method. It shows the degree evaluation value and the center.

FIG. 3A shows a maximum inscribed circle (B1) surrounding the circular figure (F0) under the influence of the unique area (FS) of the circular figure (F0).
The roundness evaluation value (RB1) expressed by two radius differences (RB1) from the circle (B12) concentric with the circular figure concentrically with the circle (1), ie, the circularity error, is shown. ) Center (BO1) determined by inscribed circle center method (BO1)
It is.

However, in general, an evaluation object of a necessary and useful cylindrical shape in a production process is a circularity evaluation obtained from a shape excluding a notch (FS) of a unique region in a part of the cylindrical shape. A value was being sought.

In recent years, there has been invented a method of obtaining a roundness evaluation value from a shape excluding a notch (FS) of a unique region in a part of a cylindrical shape. FIG. 3B shows the circularity evaluation value, that is, the circularity error, obtained by the inscribed circle center method from the shape excluding the notch (FS) of the singular region in a part of the cylindrical shape. The notch (FS) of the specific region is indicated by a broken line for clarity.

When comparing FIG. 3A and FIG. 3B, the calculated roundness evaluation values (RB1, RB2) of the inscribed circle center method and the positions of the inscribed circle centers (BO1, BO2) are different. The value is calculated. In other words, it was effective in a cylindrical shape in which most of the necessary and useful columnar evaluation targets in the production process were constituted by a circle, and a small portion was constituted by a non-circle or another unique region.

In FIG. 3, the roundness evaluation value obtained by the inscribed circle center method has been described. However, the same applies to the other center methods described above.

However, in the case of a cylindrical shape, such as a piston, in which most of the evaluation targets of the cylindrical shape necessary and useful in the production process are formed of non-circular or other unique regions, the above-described method does not allow the evaluation. Can not.

In recent years, in particular, it has been designed to evaluate the roundness and the shape of a cylindrical shape of a workpiece having a unique area such as a notch in a part of a cylindrical shape and a piston manufactured for a non-circular shape from the design time. A value collation method (tentative name) has been implemented.

In the following, the difference between the design value comparison method and the centering method will be described using a table rotation type roundness measuring machine as an example, but the same applies to a detector rotation type roundness measuring device. In addition, a description will be given in comparison with the roundness evaluation value obtained by the inscribed circle center method, but the same applies to the other center methods described above.

FIG. 4 is a diagram in which the design values of a cylindrical work whose evaluation target is mostly composed of a non-circular or other unique region are recorded with reference to the origin coordinates (302) of the design values on polar coordinates ( 301).

FIG. 5 shows a figure obtained by measuring a cylindrical workpiece manufactured based on the design values shown in FIG. 4 with a roundness measuring machine and recording the rotation center (352) of the roundness measuring machine as a reference. 3
51).

FIG. 6 shows the roundness evaluation values obtained by the inscribed circle center method for the figure (301) in which the design values of FIG. 4 are recorded. That is, the roundness evaluation value (30
6) is a figure (30) obtained when recorded on polar coordinates.
1) is represented by two radius differences between a maximum inscribed circle (303) surrounding the circle and a circle (304) concentrically circumscribing the circular figure, and the center (305) of the two already circles (303, 304) is the inscribed circle. The center (305) obtained by the center method. At this time, the origin coordinates (302) have no relation to the calculation of the center position.

FIG. 7 shows the roundness evaluation value (356) obtained by calculating the recorded figure (351) shown in FIG. 5 by the inscribed circle center method. That is, the roundness evaluation value (356)
Is a circular figure (35) obtained when recorded on polar coordinates.
1) is represented by two radius differences between a maximum inscribed circle (353) surrounding the circle and a circle (354) concentrically circumscribing the circular figure, and the center (355) of the two circles (353, 354) is the inscribed circle. The center (355) obtained by the center method. Further, the difference between the center (355) obtained by the inscribed circle center method and the rotation center (352) of the roundness measuring machine is caused by the misalignment of the workpiece with respect to the rotation center (352) of the roundness measuring machine. Quantity.

FIG. 8 shows a circularity evaluation value (36) obtained from the recorded graphic (351) of FIG. 5 by a design value comparison method.
8). That is, the roundness evaluation value (3
68) Measures a cylindrical workpiece manufactured based on the design value with a roundness measuring machine, and minimizes the sum of deviations at each rotation angle between the design value (301) and the recorded figure (351). The deviation (366) from the design value (301) to the graphic (363) in which the recorded graphic of the design value is moved to the minimum value of the deviation that is a deviation on the minus side with respect to the design value (301)
And the sum (368) of the deviation (367) up to the graphic (364) obtained by moving the recorded graphic of the design value to the maximum value of the deviation which is a deviation on the plus side with respect to the design value (301). It was done.

As shown in FIG. 4, FIG. 5, FIG. 6, FIG. 7, and FIG. 8, most of the objects to be evaluated are cylindrical workpieces composed of non-circular or other unique regions from the design time. In order to evaluate the shape of a cylindrical shape, a design value matching method is useful. In the design value comparison method (FIG. 8), the origin coordinates (302) of the design values on the polar coordinates are obtained by interpolating the amount of misalignment with the rotation center (352) of the roundness measuring device to obtain the design value comparison. , And the shape evaluation of the columnar shape is used as a central reference point when displaying a figure.

Usually, the rotation axis (Z0), which is the reference axis of the roundness measuring machine, does not coincide with the axis of the work calculated by the center method. That is, the axis of the workpiece has a misalignment and an inclination with respect to the reference axis.

A method and an apparatus for correcting the misalignment of the axis of the work calculated by the center method with respect to the reference axis are well-known calculation methods and means. Further, a method and an apparatus for correcting the inclination of the axis of the workpiece calculated by each of the center methods with respect to the reference axis are well-known calculation methods and means.

The center deviation of the axis of a workpiece such as a workpiece having a unique area such as a notch in a part of a cylindrical shape or a piston manufactured for a non-circular shape from the design time, and the inclination of the axis of the workpiece. When performing the correction, the shape evaluation using the axis of the workpiece calculated by each of the center methods described above is, as described above, most of the evaluation targets of the cylindrical shape necessary and useful in the production process are non-circular or The evaluation cannot be performed with a cylindrical shape composed of other unique regions.

The present invention has been made in view of the above problems, and in particular, works such as a piston having a unique area such as a notch in a part of a cylindrical shape and a piston manufactured for a non-circular shape from the design time. And a method and apparatus useful for obtaining a cylindrical shape.

[0028]

According to the present invention, in order to solve the above-mentioned problems, the origin coordinate (302) of the design value is positioned as a reference axis of the work, and is used as a reference axis of the work for eccentricity correction and inclination correction. It is used. That is, the value of the shape set at the time of designing the work is input to the roundness measuring machine, the input value is compared with a detection signal obtained from the measurement of the cylindrical shape, and the roundness error is calculated and evaluated. It is.

[0029]

FIG. 9 is a flowchart showing a specific example of the operation of the present invention. The flow will be described. In addition, although it demonstrates as a table rotation type roundness measuring machine, it is the same also in a detector rotation type roundness measuring device. Also, the shape at the work height position where the detector abuts is called a cross-sectional shape, and the first, second,.
Described as N cross-sectional shape.

Design value file (101) for first cross-sectional shape
Enter the design value into. The design values are input to the design value file (102) of the second sectional shape. The design values are input to all the design value files (103) up to the N-th cross-sectional shape. Register and save the design value file (101) of the first cross-sectional shape, the design value file (102) of the second cross-sectional shape, and all the design value files (103) up to the N-th cross-sectional shape (1).
04).

Start of measurement (105) The registered and saved design value file is called (106).
The first cross-sectional shape is measured (107). Using the design value file of the first cross-sectional shape and the measurement data of the first cross-sectional shape, the roundness shape error and the coordinate origin of the design value are calculated by a design value matching method. (108) Measure the second cross-sectional shape. (109) Using the design value file of the second cross-sectional shape and the measurement data of the second cross-sectional shape, the roundness shape error and the coordinate origin of the design value are calculated by a design value matching method. (110)

The inclination correction and the eccentricity correction are performed using the coordinate origin calculated for the first cross-sectional shape and the coordinate origin calculated for the second cross-sectional shape. (111) (112) Although the tilt correction and the eccentricity correction in this section are described to be performed using the moving means for performing the tilt correction and the eccentricity correction attached to the turntable (FIG. 10), There is also a method of performing tilt correction and eccentricity correction by interpolating a signal. No.
Measure the N-section shape sequentially. (113) The design value file of the N-th cross-sectional shape and the measurement data of the N-th cross-sectional shape are sequentially used, and the roundness shape error of each cross-sectional shape and the coordinate origin of the design value are calculated by a design value matching method. (11
4) Calculate the cylindrical shape error (concentricity, coaxiality, cylindricity, etc.) based on the axis of the item (l) on which the tilt correction and the eccentricity correction have been performed. (115) The calculated roundness shape error and column shape error of each cross-sectional shape are displayed. (116) End (117)

[0033]

As described above, in the case of evaluating a cylindrical shape in which most of the necessary and useful cylindrical shape evaluation targets in the production process are composed of a non-circular shape and other unique regions, the work is transferred to a roundness measuring machine. The design value of the shape set at the time of design is input, the input value is compared with the detection signal obtained from the measurement of the cylindrical shape, and the axis position is calculated using the axis obtained by the design value matching method. This has made it possible to evaluate cylindrical shapes composed of non-circular and other unique regions.

Also, there is no problem if the method is used for evaluation of a general cylindrical shape having no non-circular shape or other peculiar area, and the same seismic intensity / coaxiality / cylindricity of the cylindrical shape can be calculated.

The axes for which the eccentricity correction and the inclination correction are performed are not limited to the axes obtained by the design value comparison method, the circumscribed circle center method, the inscribed circle center method, the minimum area center method, and the least square center method. May be used in combination with the center calculated by each center method.

The present invention may be used for detecting displacement in the vertical direction, and may be used for horizontal adjustment (leveling correction).

[Brief description of the drawings]

Fig. 1 Roughness of the reference axis of the roundness measuring machine Fig. 1 (A) Table rotation type Fig. 1 (B) Detector rotation type

Fig. 2 Calculating means of the workpiece axis Fig. 2 (A) Center of circumscribed circle Fig. 2 (B) Center of inscribed circle Fig. 2 (C) Minimum area center method Fig. 2 (D) Least square center method

FIG. 3 is a diagram illustrating a method for calculating the roundness of a work having a notch. FIG. 3A is an example of a roundness calculating device using the inscribed circle center method. FIG. Example of roundness calculation means

FIG. 4 shows an example of a design value shape of a non-circular work.

FIG. 5 shows an example of a measurement record figure of a non-circular work.

FIG. 6 is an example in which the design value of a non-circular workpiece is evaluated for roundness error by the inscribed circle center method.

FIG. 7 is an example in which a measurement record figure of a non-circular workpiece is evaluated for roundness error by the inscribed circle center method.

FIG. 8 is an example in which a measured record figure of a non-circular work is evaluated for roundness error by a method based on design value comparison.

FIG. 9 is a flowchart of a specific example of the operation according to the present invention.

FIG. 10: Tilt correction and eccentricity correction by comparing design values of the first section and the second section.

[Explanation of symbols]

301 Example of design value shape of non-circular work 302 Coordinate of origin of design value of non-circular work 351 Example of measurement record figure of non-circular work 352 Center of rotation of roundness measuring machine 368 Roundness evaluation value by design value verification 101 Creation of design value file for first cross section 102 Creation of design value file for second cross section 108 Comparison of design value file for first cross section with measured data 110 Comparison of design value file for second cross section with measured data 111 Work Eccentricity correction operation 112 Work inclination correction operation 114 Comparison of design value and measurement data of each section 115 Calculation of evaluation value of each section

[Procedure amendment]

[Submission date] July 26, 2000 (2007.2
6)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Full text

[Correction method] Change

[Correction contents]

[Document Name] Statement

Patent application title: Roundness measuring method and apparatus

[Claims]

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a method for rotating a workpiece (hereinafter referred to as a "workpiece") or a detector to determine the roundness or cylindrical shape of a workpiece (hereinafter simply referred to as "roundness"). It relates to a roundness measuring apparatus for measuring, in particular the inclination correction and shape evaluation of such fabricated such as a piston a non-circular for the purpose of work and design time with the specificity region, such as notches in a portion of cylindrical shape The present invention relates to a method and an apparatus for shape measurement suitable for a case.

[0002]

2. Description of the Related Art Radius method roundness measuring device (hereinafter simply referred to as "roundness measuring device") is JIS B 7451-1991 "roundness measuring device".
Is standardized Te, it reproduces the reference circle close to the geometric circle by roundness measuring machine, is relatively rotated around the object to be measured detector as a reference axis of the central detector comparing the reference circle obtained from the displacement signal of the reference axis, and evaluating.

[0003] Roundness measuring machines can be broadly classified into table rotating roundness measuring machines and detector rotating roundness measuring machines. (FIG. 1) As shown in FIG. 1 (A), a table rotation type roundness measuring machine includes a rotation axis (Z0), which is an ideal reference axis with high accuracy obtained by rotating a rotary table. The center and the axis of the work are calculated from the displacement signal of the detector obtained by rotating the rotary table by the detector abutting on the cylindrical surface of the work placed on the rotary table. As shown in FIG. 1 (B), the detector rotation type roundness measuring machine mounts a rotary axis (Z0), which is an ideal reference axis with high accuracy obtained by rotating a rotary bearing, on a table. The center of the work and the center of the work are obtained from the displacement signal of the detector obtained from the rotation of the rotary bearing by the detector mounted on the rotary bearing on the cylindrical surface of the placed work .
And the axis are calculated.

[0004] calculation means of the center and the axis of the workpiece circumscribed circle center method, inscribed circle center method, the minimum area center method and the least square center method is centered and the axis of calculation methods well known work. (Fig. 2)

In the circumscribed circle center method, as shown in FIG. 2A, a minimum circumscribed circle surrounding a circular figure (W0) obtained when a displacement signal of a detector (hereinafter referred to as a "detection signal") is recorded on polar coordinates. In a roundness evaluation method represented by the two radius differences between the circle (A1) and the circle (A2) concentric with the circle (W0), the center (AO) of the two circles (A1, A2) is The center (AO) determined by the circumcircle center method.

In the inscribed circle center method, as shown in FIG.
Roundness evaluation represented by two radius differences between a maximum inscribed circle (B1) surrounding a circular figure (W0) obtained when a detection signal is recorded on polar coordinates and a circle (B2) concentrically circumscribing a circular figure. In the method, the center (BO) of the two existing circles (B1, B2) is the center (BO) obtained by the inscribed circle center method.

In the minimum area centering method, as shown in FIG. 1C, a circle (C1) inscribing a circular figure (W0) obtained when a detection signal is recorded on polar coordinates and a circle (C1) circumscribing a circle are concentric. In the roundness evaluation method represented by the radius at which the difference between the two radii becomes minimum, the center (CO) of the two already-existing circles (C1, C2) is the center (CO) obtained by the minimum area center method.

In the least squares method, as shown in FIG. 1D, a perfect circle is arranged on a circular figure (W0) obtained when a detection signal is recorded on polar coordinates, and a radius difference between the perfect circle and the circular figure is obtained. In other words, the circle having the smallest square of the error is defined as the reference circle (D1), and the true circle represented by the two radius differences between the circumscribed circle (D2) concentric with the existing reference circle and the inscribed circle (D3) concentric with the existing reference circle. In the roundness evaluation method, the reference circle (D1) and the two existing circles (D2, D
The center (DO) of 3) is the center (DO) obtained by the least square center method.

FIG. 3 is a diagram showing a true circle obtained by calculating a circular figure obtained by recording a detection signal of a work having a notch which is a unique area in a part of a cylindrical shape on polar coordinates by using the inscribed circle center method. It shows the degree evaluation value and the center.

FIG. 3A shows a maximum inscribed circle (B1) surrounding the circular figure (F0) under the influence of the unique area (FS) of the circular figure (F0).
The roundness evaluation value (RB1) expressed by two radius differences (RB1) from the circle (B12) concentric with the circular figure concentrically with the circle (1), ie, the circularity error, is shown. ) Center (BO1) determined by inscribed circle center method (BO1)
It is.

However, in general, an evaluation object of a necessary and useful cylindrical shape in a production process is a circularity evaluation obtained from a shape excluding a notch (FS) of a unique region in a part of the cylindrical shape. A value was being sought.

In recent years, there has been invented a method of obtaining a roundness evaluation value from a shape excluding a notch (FS) of a unique region in a part of a cylindrical shape. FIG. 3B shows the circularity evaluation value, that is, the circularity error, obtained by the inscribed circle center method from the shape excluding the notch (FS) of the singular region in a part of the cylindrical shape. The notch (FS) of the specific region is indicated by a broken line for clarity.

When comparing FIG. 3A and FIG. 3B, the calculated roundness evaluation values (RB1, RB2) of the inscribed circle center method and the positions of the inscribed circle centers (BO1, BO2) are different. The value is calculated. In other words, in the case of a cylindrical shape where most of the evaluation target of the necessary and useful cylindrical shape in the production process is composed of a circle, and a small portion is composed of a non-circular shape and other singular regions, the notch (FS From the shape excluding)
The method of obtaining the roundness evaluation value was effective.

In FIG. 3, the roundness evaluation value obtained by the inscribed circle center method has been described. However, the same applies to the other center methods described above.

However, in the case of a cylindrical shape, such as a piston, in which most of the evaluation targets of a cylindrical shape which is necessary and useful in the production process are constituted by non-circular or other special regions, the above-described method is used. Can not.

In recent years, in order to evaluate the roundness and the shape of a cylindrical shape, for example , a workpiece having a unique area such as a notch in a part of a cylindrical shape and a non-circular shape manufactured from the design time, for example, a piston, A design value matching method (tentative name) is being performed.

In the following, the difference between the design value comparison method and the centering method will be described using a table rotation type roundness measuring machine as an example, but the same applies to a detector rotation type roundness measuring device. In addition, a description will be given in comparison with the roundness evaluation value obtained by the inscribed circle center method, but the same applies to the other center methods described above.

As an actual example, FIG. 4 shows a design value of a cylindrical work in which a large part of the evaluation object is formed of a non-circular or other singular region, and the origin coordinates (302) of the design values on polar coordinates.
Is a figure (301) recorded on the basis of.

FIG. 5 shows a figure obtained by measuring a cylindrical workpiece manufactured based on the design values shown in FIG. 4 with a roundness measuring machine and recording the rotation center (352) of the roundness measuring machine as a reference. 3
51).

FIG. 6 shows the roundness evaluation values obtained by the inscribed circle center method for the figure (301) in which the design values of FIG. 4 are recorded. That is, the roundness evaluation value (30
6) is a figure (30) obtained when recorded on polar coordinates.
1) is represented by two radius differences between a maximum inscribed circle (303) surrounding the circle and a circle (304) concentrically circumscribing the circular figure, and the center (305) of the two already circles (303, 304) is the inscribed circle. The center (305) obtained by the center method. In this case, set
The origin coordinate (302) of the measured value has no relation to the calculation of the center position.

FIG. 7 shows the roundness evaluation value (356) obtained by calculating the recorded figure (351) shown in FIG. 5 by the inscribed circle center method. That is, the roundness evaluation value (356)
Is a circular figure (35) obtained when recorded on polar coordinates.
1) is represented by two radius differences between a maximum inscribed circle (353) surrounding the circle and a circle (354) concentrically circumscribing the circular figure, and the center (355) of the two circles (353, 354) is the inscribed circle. The center (355) obtained by the center method. Further, the difference between the center (355) obtained by the inscribed circle center method and the rotation center (352) of the roundness measuring machine is caused by the misalignment of the workpiece with respect to the rotation center (352) of the roundness measuring machine. Quantity.

FIG. 8 shows a circularity evaluation value (36) obtained from the recorded graphic (351) of FIG. 5 by a design value comparison method.
8). That is, the roundness evaluation value (3
68) Measures a cylindrical workpiece manufactured based on the design value with a roundness measuring machine, and minimizes the sum of deviations at each rotation angle between the design value (301) and the recorded figure (351). The deviation (366) from the design value (301) to the graphic (363) in which the recorded graphic of the design value is moved to the minimum value of the deviation that is a deviation on the minus side with respect to the design value (301)
And the sum (368) of the deviation (367) up to the graphic (364) obtained by moving the recorded graphic of the design value to the maximum value of the deviation which is a deviation on the plus side with respect to the design value (301). It was done.

As shown in FIG. 4, FIG. 5, FIG. 6, FIG. 7, and FIG. 8, the columnar shape of a cylindrical work in which a large part of the evaluation target is constituted by a non-circular or other unique region from the design time. For the shape evaluation, a design value comparison method is useful. In the design value comparison method (FIG. 8), the origin coordinates (302) of the design values on the polar coordinates are obtained by interpolating the amount of misalignment with the rotation center (352) of the roundness measuring device to obtain the design value comparison. , And the shape evaluation of the columnar shape is used as a central reference point when displaying a figure.

Usually, the rotation axis (Z0), which is the reference axis of the roundness measuring machine, does not coincide with the axis of the work calculated by the center method. That is, the axis of the workpiece has a misalignment and an inclination with respect to the reference axis.

A method and an apparatus for correcting the misalignment between the center of the work and the axis calculated by the center method with respect to the reference axis are well-known calculation methods and means. Further, a method and an apparatus for correcting the inclination of the axis of the workpiece calculated by each of the center methods with respect to the reference axis are well-known calculation methods and means.

The center deviation of the axis of a workpiece such as a workpiece having a unique area such as a notch in a part of a cylindrical shape or a piston manufactured for a non-circular shape from the design time, and the inclination of the axis of the workpiece. When performing the correction, the shape evaluation using the axis of the workpiece calculated by each of the center methods described above is, as described above, most of the evaluation targets of the cylindrical shape necessary and useful in the production process are non-circular or The evaluation cannot be performed with a cylindrical shape composed of other unique regions.

[0027] The present invention has been made in consideration of the above problems, in particular as a work and design time with the specificity region, such as notches in a portion of cylindrical shape, such as fabricated such as a piston a non-circular for the purposes A method and an apparatus useful for obtaining a cylindrical shape of a work.

[0028]

The present invention SUMMARY OF] In order to solve the above problems, in the origin coordinates of the design value (302) of the workpiece
It is positioned as a center and a reference axis, and is used as a reference axis of a workpiece for eccentricity correction and tilt correction. That is, the value of the shape set at the time of designing the work is input to the roundness measuring machine, the input value is compared with a detection signal obtained from the measurement of the cylindrical shape, and the roundness error is calculated and evaluated. It is.

[0029]

FIG. 9 is a flowchart showing a specific example of the operation of the present invention. The flow will be described. In addition, although it demonstrates as a table rotation type roundness measuring machine, it is the same also in a detector rotation type roundness measuring device. Also, the shape at the work height position where the detector abuts is called a cross-sectional shape, and the first, second,.
Described as N cross-sectional shape.

Design value file (101) for first cross-sectional shape
Enter the design value into. The design values are input to the design value file (102) of the second sectional shape. The design values are input to all the design value files (103) up to the N-th cross-sectional shape. Register and save the design value file (101) of the first cross-sectional shape, the design value file (102) of the second cross-sectional shape, and all the design value files (103) up to the N-th cross-sectional shape (1).
04).

Start of measurement (105) The registered and saved design value file is called (106).
The first cross-sectional shape is measured (107). Using the design value file of the first cross-sectional shape and the measurement data of the first cross-sectional shape, the roundness shape error and the coordinate origin of the design value are calculated by a design value matching method. (108) Measure the second cross-sectional shape. (109) Using the design value file of the second cross-sectional shape and the measurement data of the second cross-sectional shape, the roundness shape error and the coordinate origin of the design value are calculated by a design value matching method. (110)

The inclination correction and the eccentricity correction are performed using the coordinate origin calculated for the first cross-sectional shape and the coordinate origin calculated for the second cross-sectional shape. (111) (112) Although the tilt correction and the eccentricity correction in this section are described to be performed using the moving means for performing the tilt correction and the eccentricity correction attached to the turntable (FIG. 10), There is also a method of performing tilt correction and eccentricity correction by interpolating a signal. No.
Sequentially measuring the in N cross-sectional shape or. (113) The design value file of the N-th cross-sectional shape and the measurement data of the N-th cross-sectional shape are sequentially used, and the roundness shape error of each cross-sectional shape and the coordinate origin of the design value are calculated by a design value matching method. (11
4) The tilt correction and the eccentricity correction ( 111 and 1 ) were performed.
12 ) The cylindrical shape error (concentricity /
Calculate coaxiality / cylindricity). (115) The calculated roundness shape error and column shape error of each cross-sectional shape are displayed. (116) End (117)

[0033]

As described above, in the case of evaluating a cylindrical shape in which most of the necessary and useful cylindrical shape evaluation targets in the production process are composed of a non-circular shape and other unique regions, the work is transferred to a roundness measuring machine. Input the design value of the shape set at the time of design, the detection value obtained from the input value and the measurement of the cylindrical shape
Then, by calculating the position of the axis using the axis obtained by the method of design value comparison, it became possible to evaluate a non-circular shape and a cylindrical shape composed of other singular regions.

Further, no harm no be used to evaluate the general cylindrical shape that does not have a non-circular or other specific area, the heart of, concentricity, cylindricity, which is a cylindrical shape can be calculated.

The axes for which the eccentricity correction and the inclination correction are performed are not limited to the axes obtained by the design value comparison method, the circumscribed circle center method, the inscribed circle center method, the minimum area center method, and the least square center method. Any of the centers obtained by each center method calculated by
One may be used in combination.

The present invention may be used for detecting displacement in the vertical direction, and may be used for horizontal adjustment (leveling correction).

[Brief description of the drawings]

Fig. 1 Roughness of the reference axis of the roundness measuring machine Fig. 1 (A) Table rotation type Fig. 1 (B) Detector rotation type

Fig. 2 Calculating means of the workpiece axis Fig. 2 (A) Center of circumscribed circle Fig. 2 (B) Center of inscribed circle Fig. 2 (C) Minimum area center method Fig. 2 (D) Least square center method

FIG. 3 is a diagram illustrating a method for calculating a roundness of a work having a notch FIG. 3 (A) An example of a method for calculating a roundness based on an inscribed circle center method FIG. 3 (B) is based on an inscribed circle center method excluding a notched portion Example of roundness calculation method

FIG. 4 shows an example of a design value shape of a non-circular work.

FIG. 5 shows an example of a measurement record figure of a non-circular work.

FIG. 6 is an example in which the design value of a non-circular workpiece is evaluated for roundness error by the inscribed circle center method.

FIG. 7 is an example in which a measurement record figure of a non-circular workpiece is evaluated for roundness error by the inscribed circle center method.

FIG. 8 is an example in which a measured record figure of a non-circular work is evaluated for roundness error by a method based on design value comparison.

FIG. 9 is a flowchart of a specific example of the operation according to the present invention.

FIG. 10: Tilt correction and eccentricity correction by comparing design values of the first section and the second section.

[Description of Signs] 301 Example of Design Value Shape of Non-circular Work 302 Origin Coordinate of Design Value of Non-Circular Work 351 Example of Measurement Recorded Graphic of Non-Circular Work 352 Rotation Center of Roundness Measuring Machine 368 True by Design Value Verification Circularity evaluation value 101 Creation of design value file for first section 102 Creation of design value file for second section 108 Comparison of design value file for first section shape with measurement data 110 Design value file and measurement data for second section shape Comparison 111 Work eccentricity correction operation 112 Work inclination correction operation 114 Comparison of design values and measurement data of each cross section 115 Calculation method of evaluation value of each cross section

Claims (8)

[Claims] 1. A circularity measuring device having a rotating mechanism and measuring a change in a circumferential radius or a change in a circumferential direction and an axial direction radius of an object to be measured by a detector. Inputting the design values to a design value file and storing the design values; measuring the shape of the object to be measured at a plurality of measurement positions at different heights and storing the measured values as measurement data; Comparing the measured data and calculating an arbitrary coordinate value of the design value as a center by design value comparison of the measured object; calculating a center of the design value comparison at the measurement position as an axis; A step of calculating the amount of deviation between the rotation axis of the circularity measuring device and the axis calculated from the center of the design value comparison, and based on the calculated amount of deviation at each measurement position, at any measurement position Calculate the amount of tilt of the DUT and calculate the tilt Moving the amount of inclination so that the displacement becomes zero, and making the axis of the roundness measuring machine parallel to the axis calculated from the center of the design value comparison of the measured object. A roundness measuring method characterized by the following. 2. A circularity measuring device having a rotating mechanism, wherein a detector measures a change in a circumferential radius or a change in a radius in a circumferential direction and a change in a radius in an axial direction by a detector. Inputting the design values to a design value file and storing the design values; measuring the shape of the object to be measured at a plurality of measurement positions at different heights and storing the measured values as measurement data; Comparing the measured data and calculating an arbitrary coordinate value of the design value as the center by comparing the design value of the object to be measured; a circumscribed circle center method, an inscribed circle center method, a minimum area center method, and a least square center method Calculating a center at a plurality of measurement positions having different heights, and a center of a circumscribed circle center method, an inscribed circle center method, a minimum area center method, a least square center method, and a center of the design value comparison at the measurement position. The process of calculating the mind and measuring roundness Calculating the amount of deviation between the rotation axis of the machine and the calculated axis, based on the calculated amount of deviation at each measurement position, calculating the amount of tilt of the object to be measured at any measurement position Moving the amount of inclination so that the amount of inclination becomes zero, thereby making the axis of the roundness measuring machine parallel to the axis of the object to be measured. Degree measurement method. 3. A circularity measuring device having a rotation mechanism, wherein a detector measures a change in a circumferential radius or a change in a radius in a circumferential direction and a change in a radius in an axial direction with a detector. Inputting the design values to a design value file and storing the design values; measuring the shape of the object to be measured at a plurality of measurement positions at different heights and storing the measured values as measurement data; Comparing the measured data and calculating an arbitrary coordinate value of the design value as a center by design value comparison of the measured object; calculating a center of the design value comparison at the measurement position as an axis; A step of calculating the amount of deviation between the rotation axis of the circularity measuring device and the axis calculated from the center of the design value comparison, and based on the calculated amount of deviation at each measurement position, at any measurement position Calculate the amount of tilt of the DUT and calculate the tilt Moving the inclination amount so that the deflection amount becomes zero, and making the axis of the roundness measuring machine and the axis calculated from the center of the design value comparison of the measured object parallel to each other; Comparing the measured data and calculating a deviation of the measured data from the design value; setting the deviation as a shape deviation; and comparing the shape deviation at a plurality of measurement positions. A method for measuring roundness, characterized in that: 4. A roundness measuring machine having a rotation mechanism, wherein a detector measures a change in a circumferential radius of a measured object or a change in a circumferential and axial radius of the measured object. Inputting the design values to a design value file and storing the design values; measuring the shape of the object to be measured at a plurality of measurement positions at different heights and storing the measured values as measurement data; Comparing the measured data and calculating an arbitrary coordinate value of the design value as the center by comparing the design value of the object to be measured; a circumscribed circle center method, an inscribed circle center method, a minimum area center method, and a least square center method The step of calculating as a center at a plurality of measurement positions having different heights, and a center of a circumscribed circle center method, an inscribed circle center method, a minimum area center method, a least square center method, and a center of the design value comparison at a plurality of measurement points. Calculating the axis center with Calculating the amount of deviation between the rotation axis of the circularity measuring device and the calculated axis, and, based on the calculated amount of deviation at each measurement position, the amount of inclination of the measured object at an arbitrary measurement position Calculating the tilt amount to move the tilt amount so that the tilt amount becomes zero, to make the axis of the roundness measuring machine parallel to the axis of the object to be measured, and the design value and the measurement data Comparing and calculating a deviation of the measurement data from the design value; setting the deviation as a shape deviation; and comparing the shape deviation at a plurality of measurement positions. Roundness measurement method. 5. A roundness measuring machine having a rotating mechanism and measuring a change in a circumferential radius or a change in a circumferential direction and an axial direction radius of an object to be measured by a detector. Means for inputting design values to a design value file and storing the design values; means for measuring shapes at a plurality of measurement positions at different heights of an object to be measured and storing the measured values as measurement data; Means for comparing measured data and calculating an arbitrary coordinate value of the design value as the center by design value comparison of the measured object; means for calculating the center of the design value comparison at the measurement position as an axis; Means for calculating the amount of deviation between the rotation axis of the circularity measuring machine and the axis calculated from the center of the design value comparison, and, based on the calculated amount of deviation at each measurement position, at any measurement position Calculate the amount of tilt of the DUT and calculate the tilt Means for moving the inclination amount so that the deflection amount becomes zero, and making the axis of the roundness measuring machine parallel to the axis calculated from the center of the design value comparison of the measured object. A roundness measuring device characterized by the above-mentioned. 6. A roundness measuring machine having a rotating mechanism and measuring a change in a circumferential radius or a change in a circumferential and axial radius of an object to be measured by a detector. Means for inputting design values to a design value file and storing the design values; means for measuring shapes at a plurality of measurement positions at different heights of an object to be measured and storing the measured values as measurement data; Means for comparing measured data and calculating an arbitrary coordinate value of the design value as a center by comparing the design value of the measured object with a circumcircle center method, an inscribed circle center method, a minimum area center method, and a least square center method Means for calculating the center at a plurality of measurement positions having different heights, and the axis of the circumscribed circle center method, the inscribed circle center method, the minimum area center method, the least square center method, and the center of the design value comparison at the measurement position. Means for calculating the mind and roundness measurement Means for calculating the amount of deviation between the rotation axis of the machine and the calculated axis, and, based on the calculated amount of deviation at each measurement position, calculating the amount of inclination of the workpiece at any measurement position Means for moving the amount of inclination so that the amount of inclination becomes zero so as to make the axis of the roundness measuring machine parallel to the axis of the object to be measured. Degree measuring device. 7. A circularity measuring device having a rotation mechanism and measuring a change in a circumferential radius or a change in a radius in a circumferential direction and a change in a radius in an axial direction of a measured object by a detector. Means for inputting design values to a design value file and storing the design values; means for measuring shapes at a plurality of measurement positions at different heights of an object to be measured and storing the measured values as measurement data; Means for comparing measured data and calculating an arbitrary coordinate value of the design value as the center by design value comparison of the measured object; means for calculating the center of the design value comparison at the measurement position as an axis; Means for calculating the amount of deviation between the rotation axis of the circularity measuring machine and the axis calculated from the center of the design value comparison, and, based on the calculated amount of deviation at each measurement position, at any measurement position Calculate the amount of tilt of the DUT and calculate the tilt Means for moving the inclination amount so that the deflection amount becomes zero, and making the axis of the roundness measuring machine parallel to the axis calculated from the center of the design value comparison of the measured object; Means for comparing measurement data, calculating a deviation of the measurement data from the design value, means for setting the deviation as a shape deviation, and means for comparing the shape deviation at a plurality of measurement positions. A roundness measuring device, characterized in that: 8. A roundness measuring machine having a rotation mechanism and measuring a change in a circumferential radius or a change in a circumferential direction and an axial direction radius of an object to be measured by a detector. Means for inputting design values to a design value file and storing the design values; means for measuring shapes at a plurality of measurement positions at different heights of an object to be measured and storing the measured values as measurement data; Means for comparing measured data and calculating an arbitrary coordinate value of the design value as a center by comparing the design value of the measured object with a circumcircle center method, an inscribed circle center method, a minimum area center method, and a least square center method Means for calculating a center at a plurality of measurement positions having different heights, and a center of a circumscribed circle center method, an inscribed circle center method, a minimum area center method, a least square center method, and a center of the design value comparison at a plurality of measurement points. Means to calculate the axis center with Means for calculating the amount of deviation between the rotation axis of the circularity measuring device and the calculated axis, and the amount of inclination of the object to be measured at an arbitrary measurement position based on the calculated amount of deviation at each measurement position Means for moving the tilt amount so that the tilt amount becomes zero, and making the axis of the roundness measuring machine parallel to the axis of the object to be measured, and calculating the design value and the measurement data. Means for comparing and calculating a deviation of the measurement data from the design value; means for setting the deviation as a shape deviation; and means for comparing the shape deviation at a plurality of measurement positions. Roundness measuring device.