JP2000249540A - Device and method for measuring shape of cylindrical object - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accurately measure the degree of cylindrical property by the V block method by separately providing a mechanism for rotating an object to be measured, detecting the position change in the normal line at a part corresponding to the contact surface with the V block of the object to be measured, and obtaining the position of the contact surface of a virtual V block that vertically touches a cylindrical object. SOLUTION: By rotating rollers 45 and 46 with a drive source, a cylindrical object 1 to be measured is rotated. The outer diameters of the rollers 45 and 46 are accurately measured, and the amount of rotation of the cylindrical object 1 can be detected from the amount of rotation. A V block measurement part 41 is composed of three sets of non-contact type tangential displacement meters consisting of light source parts 31, 34, and 37 and corresponding light reception parts 32, 35, and 38, and each light source part and light reception part are fixed in each specific position relationship. Then, by detecting the position change in the tangent line of a part corresponding to the contact surface with the V block of the cylindrical object 1 is detected by the three sets of tangential displacement meters, the position of the contact surface of the virtual V block in contact with the cylindrical object 1 virtually is accurately obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus and a method for measuring the shape of a cylindrical object, and more particularly to an apparatus and a method for measuring the shape of a cylindrical object by a V-block method.

[0002]

2. Description of the Related Art There has been a wide demand for precise measurement of the outer shape of a cylindrical machine component such as a roundness shape, and various methods have been conventionally proposed to meet such a demand, and the method has been put to practical use. Have been. A device that is widely used as a roundness measuring device is a device that supports a cylindrical object on a turntable, rotates, and detects the surface displacement with a contact or non-contact displacement meter while measuring the rotation angle. There is a so-called radius method for measuring a change in the radial direction with reference to the rotation center of the support base.
As a contact displacement meter, for example, there is an electric micrometer that detects a displacement of a probe that comes into contact with the surface of an object to be measured by a differential transformer or the like. Examples of the non-contact type displacement meter include a capacitance type and an optical sensor. The outer shape of a cross section, which is one measurement, can be measured. If such a measurement is performed at different cross sections while changing the position in the cylinder axis direction, the outer shape such as cylindricity can be measured. Since the roundness measuring machine of the radius method detects the displacement of the cylinder in the normal direction based on the mechanical rotation of the measuring machine, it is essential that the rotating mechanism be a rotating mechanism that achieves high-precision rotational accuracy. . In addition, since the deviation between the rotation center of the measuring machine and the center of the cylinder to be measured is a measurement error, it is necessary to perform centering manually or automatically in order to maintain a constant measurement accuracy. Is skilled, but when automatic, expensive equipment is required.

[0003] A three-point method is known as a relatively simple method for measuring the roundness of a cylindrical object. (1) in FIG.
FIG. 3 is a diagram for explaining a three-point method. In the three-point method, three displacement meters (here, non-contact type) 3A to 3C are arranged in three different directions, and the difference between the surface position of the cylinder 1 at that portion with respect to the reference circle 2 and the rotation of the cylinder is determined. The result is analyzed and the roundness shape is calculated by analyzing the result. It is necessary to match the detection directions of the three displacement meters at the intersection O, and the center of the cylinder and its rotation center are arranged near the intersection O. 3
The point method can measure with a simpler device than the radius method, but in order to achieve the required measurement accuracy, a certain degree of accuracy is required in the arrangement of the detector and the cylinder.

As described above, the radius method and the three-point method require a high-precision rotating mechanism and a high-precision positioning operation in order to perform high-precision measurement. Therefore, it is suitable for measurement in measurement rooms and laboratories, but it is suitable for measuring cylinders that are chucked to machine tools in the machining process or in-process measurement of cylinders being machined. Was unsuitable.

In order to efficiently process a high-precision cylindrical object, it is necessary to perform processing while measuring in-process, and it is desired to easily and accurately measure the external shape of the cylindrical object in-process. Have been. As a method for easily and accurately measuring the roundness shape of a cylindrical object, a V-block method has been conventionally known. FIG. 1B is a diagram for explaining the V-block method. In the V-block method, the cylinder 1 is placed on a V-block 4 and a displacement meter 5 for detecting the displacement of an upper portion is provided. The displacement of the upper part is processed by harmonic analysis or the like to measure the roundness shape. The V-block method has one detection point as in the above-described radius method. However, since the position of the cylindrical object 1 in two directions is defined by the V-block 4, a high-precision rotation mechanism and a high-precision position No alignment work is required, and setting for measurement is easy.

In the V-block method, a displacement meter is brought into contact with the upper part of a cylindrical object in contact with the V-block. However, if the center axis of the displacement meter deviates from the center axis of the V-block, an error occurs. The work of aligning the central axes was necessary, which hindered in-process measurement. Therefore, among the inventors of the present application, Yamada and Yanagi et al., In "Design Engineering," Vol. 30, No. 1, (1995), pp. 26-32, use the V-block method to detect displacement of a portion above a cylindrical object. instead of,
The displacement of the tangent at the top of the cylinder placed on the V block is
A V-block method roundness measuring device that detects using a small-diameter laser is disclosed. Such a displacement meter that detects a displacement of a tangent of a cylinder in a predetermined direction is called a tangential displacement meter, and a displacement that detects a surface position in a normal direction of the cylinder used in the above-described radius method or three-point method. The gauge will be referred to as a normal displacement gauge. With a tangential displacement meter, the direction of the laser beam only needs to be set accurately, which facilitates the setting operation.

[0007] The V-block method is widely used because the cylinder is easier to hold and the operation is simpler than the three-point method. However, since the cylinder is rotated with the cylinder in contact with the V-block, the cylinder is rotated. There is a problem that a scratch (scratch) is generated at a contact portion of the object with the V block. Therefore, among the inventors of the present application, Yamada and Yanagi et al.
No. (1997) pp. 264-270, supporting the cylinder on two rollers instead of a V-block and rotating,
Disclosed is a V-block method roundness measuring device that detects displacement of a tangent line above a cylindrical object using a small-diameter laser.

FIG. 2 is a diagram for explaining this method.
FIG. 1A is a perspective view showing the entire configuration, and FIG. 2B is a view as seen from the cylinder axis direction. As shown in FIG. 2, two sets of two rollers 6 and 7 driven by a synchronous motor 9 via a synchronous belt 8 are arranged on both sides, and the cylinder 1 is placed thereon and rotated. A tangential displacement meter composed of a set of a light source unit 10A that emits a parallel laser beam and a light receiving unit 11A that receives the laser beam and detects the amount of the laser beam is used. Arrange so that it is cut off. Since the amount of light received by the light receiving unit 11A changes according to the position where the upper part of the cylinder 1 blocks a part of the laser beam, the relationship between the cutoff position and the output of the light receiving unit 11A is determined in advance. Can be detected. The set of two rollers 6, 7 also has a function similar to the V block, and will be referred to as a pseudo V block. The laser beam of the tangential displacement meter is inclined at an angle β from a direction perpendicular to the center line of the pseudo V-block, in order to make it generalized and to set the magnification to an appropriate value.

[0009]

However, in the measuring device shown in FIG. 2, since the V-block constituted by the rollers 6 and 7 is displaced from the measurement position and is not a perfect V-block, the roundness measurement is performed. There was a problem that the accuracy was insufficient. Furthermore, in the V-block method, a three-dimensional outer shape can be measured by changing the position in the cylinder axis direction and performing measurement on different cross sections. However, since the V-block also serves as a support point of the cylindrical object,
The position of the V block cannot be freely arranged in the direction of the cylinder axis. If the cross-sectional shape is measured at a portion without the V block, the center of the cylinder cannot be detected, so that there is a problem that the cylindricity cannot be measured. For example, in the measuring device of FIG. 2, the installation position of the tangent position detector is shifted from the support position of the rollers 6 and 7, and cannot be said to be in the state of being supported by the V-block, and the mechanical movement error due to rotation is reduced. Because it is greatly affected, the center of the cylinder cannot be detected.

In order to increase the accuracy of the rollers 6 and 7, it is necessary to use a hard metal material or the like. Scratch scratches are much less than when a V-block is used, but the scratches are completely prevented. There was a problem that you can not do. The present invention is to improve the V-block method in view of such a problem. The first object is to improve the measurement accuracy, and the second object is to measure the cylindricity by the V-block method. The third object is to realize a V-block method that does not cause scratches.

[0011]

FIG. 3 is a diagram showing a basic configuration of a cylindrical shape measuring apparatus and a measuring method according to the present invention, wherein (1) shows a method for detecting the position of a contact surface of a virtual V-block. An example in which a contact type normal displacement meter is used to detect the displacement of the upper part of the tangential displacement meter of the type is shown, and (2) shows an example in which a non-contact type tangential displacement meter is used in all cases.

As shown in FIG. 3, in the apparatus and method for measuring the shape of a cylindrical object according to the present invention, a mechanism for rotating the object 1 is provided separately, and corresponds to the contact surface of the object 1 with the V block. By detecting a change in the position of the tangent of the portion, the position of the contact surface of the virtual V block that virtually contacts the cylinder is accurately determined, and correction is performed assuming that the position is supported by the V block at this position. As a result, the same analysis as the V-block method can be applied, and the measurement can be performed regardless of the support position of the cylindrical object.
Moreover, since it is only necessary to detect a change in the tangent position of the cylindrical object in a predetermined direction, a tangential displacement meter can be used and setting can be easily performed. Further, since the rotation center of the cylinder can be detected, the cylindricity can be measured.

In FIG. 3A, as first and second tangential displacement meters for detecting the position of the contact surface of the virtual V block, contact displacement meters 21 and 23 such as electric micrometers are used.
Are provided with flat plates 22 and 24, and a contact-type displacement meter that comes into contact with the cylindrical object 1 is used. In the present invention, since the flat plates 22 and 24 may be arranged in parallel with the contact surface of the virtual V block, the relative position with respect to the cylindrical object 1 is adjusted only by disposing the contact type displacement meters 21 and 23 in a predetermined direction. Is easy.

Similarly, in FIG. 3 (2), the first and second
As the tangential displacement meter, a non-contact tangential displacement meter using a small-diameter laser shown in FIG. 2 is used, and light source units 31 and 34 that emit parallel laser beams 33 and 36 and this laser beam are used. Light receiving unit 3 that receives light and detects the amount of light
2, 35 are arranged such that part of the laser beam is blocked at the top of the cylinder 1. Also in this case, the laser beam 3
It is only necessary to set the directions of 3 and 36, and the adjustment of the relative position with respect to the cylinder 1 is easy.

As for the upper displacement meter for detecting the displacement of the upper part of the cylindrical object, as shown in FIG. 3 (1), even if a normal displacement type displacement meter for detecting the displacement in the normal direction is used, as shown in FIG. As in (2), a tangential displacement meter that detects a tangential displacement may be used. If the displacement of the tangent line is to be detected, the same tangential displacement meter as that for detecting the position of the contact surface of the virtual V-block can be used, and the setting is easy, so that it is suitable for in-process measurement.

In order to measure the cylindricity, it is necessary to move the measurement section along the cylinder axis. The first and second tangential displacement meters and the upper displacement meter are translated in parallel along the cylinder axis. A moving means is provided. The rotating mechanism of the cylindrical object 1 holds and rotates one end of the cylindrical object like a mechanism that places the cylindrical object on a set of rollers as shown in FIG. 2 and rotates the same, or a chuck mechanism of a machine tool. Use mechanism. The rotation angle position of the cylindrical object is calculated from the number of pulses of the pulse motor that drives the roller, or detected using an encoder that detects the rotation angle position of the rotation shaft of the machine tool.

When there is a risk that the cylinder placed on the roller may slip with the rotation, a member having a rotation scale is attached to the cylinder and rotated, and the rotation scale is detected by optical or magnetic means. However, it is necessary to directly detect the rotational angle position of the cylindrical object. In this case, since the rotation mechanism does not affect the accuracy of the measurement, the rotation mechanism can be rotated by a roller or the like provided with an elastic body such as rubber on the surface. Therefore, if the first and second tangential displacement meters and the upper displacement meter are of a non-contact type as shown in FIG.

Further, if the rotation axis of the machine tool is used as the rotation means of the cylinder to be measured while the cylinder is mounted on the machine tool, it is needless to say that no scratches are caused by the measurement. As the non-contact type tangential displacement meter, one using the laser used in the example of FIG. 2 can be used.

It is practically important that the shape measuring device for a cylindrical object is capable of accommodating cylindrical objects having different diameters, and that the resetting operation when the diameter is changed is simple. In the case where the cylindrical object 1 is rotated while being supported by a set of two rollers as shown in FIG. 2, the direction of the contact surface of the virtual V block is set to a tangent near the contact point between the cylindrical object and the roller. However, even if the diameter of the cylinder 1 changes, the change in the tangential position is small.

In the non-contact tangential displacement meter using a small-diameter laser shown in FIG. 2, the detection range is determined by the diameter of the laser beam. Accordingly, if the tangential displacement meter using the small-diameter laser shown in FIG. 2 is used, the first and second tangential displacement meters that detect the position of the contact surface of the virtual V block are A laser beam having a small diameter is used, and a laser beam having a large diameter is used as an upper displacement meter. In this case, a cylinder having a wide range of diameters can be handled without resetting. However, in the tangential displacement meter using the small-diameter laser shown in FIG. 2, when the diameter of the laser beam increases, the accuracy of detecting the displacement decreases. Therefore, when a laser beam having a small diameter is used also for the upper displacement meter, a moving means for moving the upper displacement meter in the normal direction of the object to be measured is provided so that the upper displacement meter can cope with cylinders having various diameters. It is desirable to do so. Furthermore, a tangential displacement meter using a small diameter laser used as an upper displacement meter can emit a laser beam with a large diameter, but if the diameter is limited by an aperture, the detection accuracy does not decrease, so
The aperture for reducing the diameter may be moved. If a wide displacement detection range is required for the first and second tangential displacement meters, it is desirable to provide a similar mechanism.

[0021]

FIG. 4 is a view showing a configuration of a cylindrical shape measuring apparatus according to a first embodiment of the present invention, and a computer constituting a data processing section for calculating an external shape from a detected tangent position. Are provided, but are omitted here. As shown in FIG. 4, a rotation mechanism 44 is provided at both ends of the linear guide 42 for rotating the cylinder 1 mounted thereon. This rotation mechanism 44 has rollers 45 and 46 on both sides.
By rotating the rollers 45 and 46 by a driving source such as a pulse motor (not shown),
The placed cylinder 1 rotates. The surface of the rollers 45 and 46 is provided with a layer of an elastic material such as rubber, for example, so that the surface of the cylindrical body 1 is not damaged even when rotated. The outer diameter of the rollers 45 and 46 is accurately measured, and the rotation amount of the rollers 45 and 46 can be detected by counting the number of pulses of a pulse motor or the like. Since no slip occurs between the cylinders 1, the rotation amount of the cylinder 1 can be detected from the rotation amounts of the rollers 45 and 46.

The V-block measuring section 41 is a first non-contact tangential displacement meter using a laser composed of a light source section 31 and a light receiving section 32, as shown in FIG. When,
It has a second non-contact tangential displacement meter composed of a light source unit 34 and a light receiving unit 35, and a third non-contact tangential displacement meter composed of a light source unit 37 and a light receiving unit 38. Light source 3
1, 34, 37 and the light receiving sections 32, 35, 28 are fixed to the V block measuring section 41 in a predetermined positional relationship. That is, the directions of the laser beams emitted from the light sources 31, 34, and 37 have a predetermined angular relationship. The V block measuring unit 41 is mounted on a movable table 43 that can move along a linear guide 42.

FIG. 5 is a diagram illustrating the principle of a non-contact tangential displacement meter using a laser. In the light source unit 51,
A laser diode and a collimator lens for converting a laser beam emitted from the laser diode into a parallel laser beam are provided. A laser diode that oscillates stably without occurrence of mode hopping or the like is used, and is feedback-controlled so as to always output a laser beam having a constant intensity. Since the cross section of the waveguide of the laser diode is fine, the laser beam emitted from the laser diode spreads largely due to diffraction, and is converted into a parallel beam by a collimator lens. In the light receiving section 52,
A condensing lens for condensing the incident laser beam and a light receiving element such as a photodiode are provided.

The light source section 51 and the light receiving section 52 are arranged as shown in FIG. In this state, the edge 54 is moved up and down,
When a part of the laser beam is cut off, the amount of the laser beam received by the light receiving unit 52 changes. Since the amount of received light simply increases and decreases according to the position of the edge 54, if the correlation between the position of the edge 54 and the amount of received light is measured in advance,
The position of the edge 54 is determined according to the amount of received light. Although it is possible to theoretically derive the correlation between the position of the edge 54 and the amount of received light by considering the laser beam as a Gaussian beam, it is necessary to cut off the laser beam when the laser beam is actually arranged in the V-block measuring unit 41. It is desirable to arrange the cylinder and store the change in the amount of received light when the position of the cylinder is changed, and obtain the correlation between the position of the cylinder and the amount of received light.

As is clear from FIG. 5, even if the edge 54 moves parallel to the direction of the laser beam, the amount of received light hardly changes. Also, what is detected is the change in the position of the tangent of the cylinder parallel to the laser beam, and the change in the position of the tangent is detected from the change in the amount of received light at the time of initial setting.
It is sufficient that the surface of the cylinder blocks a part of the laser beam.
Therefore, the measurement can be performed within a range where a part of the laser beam of the first to third non-contact tangential displacement meters arranged in the V-block measuring section 41 is blocked by the cylinder 1.

As a non-contact type tangential displacement meter using a laser, in addition to the above-described method of detecting a change in the amount of received light, a thin laser beam is scanned by a polygon mirror or the like. There is also a method of installing a photodetector that detects the laser beam in synchronization with scanning, arranging the surface of the cylinder within the scanning range, and detecting the surface position of the cylinder from the detection timing of the photodetector. Yes, such a system can also be used.

Next, the principle of measuring the cross-sectional shape of a cylindrical object and the data processing according to the virtual V-block method of the present invention will be described with reference to FIG. 6. First, a normal V-block is used instead of the virtual block. The case where there is one will be described. FIG. 6 (1) shows a cylindrical block 1 having a V block 4 having an angle α.
And a third non-contact tangential displacement meter using a laser composed of a light source unit 37 and a light receiving unit 38 to measure the position of the upper tangent line. Laser beam 3
Reference numeral 9 denotes an angle β inclined from a direction perpendicular to the center axis of the V block 4. The center of the cylinder 1 is O, the distance from that to the tangent detected by the tangential displacement meter is r _U , the distance to the contact point with the left slope of the V block 4 is r _L , and the contact point with the right slope Is defined as r _R. At this time, the distance y (θ) from the tangent detected by the tangential displacement meter to the valley of the V block 4 is expressed by the following equation (1).

[0028]

(Equation 1)

This is subjected to Fourier series expansion, and the formula is rearranged as shown in formula (2).

[0030]

(Equation 2)

At this time, a ₀ represents the average radius of the section to be measured. The second term on the right side represents the magnitude of the angular frequency component. μ is called an enlargement factor, and the measured roundness shape is enlarged and measured by the enlargement factor for each angular frequency. That is, since the magnification factor changes with the angle β, the angle β is appropriately set according to the measurement target. In the case of the virtual V block method, as shown in (2) of FIG.
Instead of the block 4, a first non-contact tangential displacement meter composed of a light source unit 31 and a light receiving unit 32, and a second non-contact tangential displacement meter composed of a light source unit 34 and a light receiving unit 35 Displacement gauges are arranged so that the laser beams 33 and 36 are parallel to the slope of the V block 4, and the distances r _L ′ and r _R ′ of the tangent from the center O are measured. At this time, the distance y ′ (θ) from the tangent detected by the upper tangential displacement meter to the valley of the virtual V block is expressed by the following equation (3).

[0032]

(Equation 3)

In the virtual V block method, the cylindrical object 1 is not supported by the V block, but is separately supported at the support points (rollers 45 and 46).
, R _L ′ and r _R ′ are δ in r _L and r _R respectively.
_L, a value obtained by adding the rotation error of [delta] _R. r _U is the same. Therefore, equation (3) becomes the following equation (4).

[0034]

(Equation 4)

Since the errors δ _L and δ _R are detected by the first and second non-contact tangential displacement meters, respectively, if y ′ (θ) is corrected according to the following equation (5), y ( θ) is obtained.

[0036]

(Equation 5)

As described above, even when the virtual V-block method is used, the same measurement result as that of the V-block method can be obtained. Is the same as Here, the description of the harmonic analysis processing is omitted. As described above, the center position of the cylindrical object 1 is displaced in the virtual V-block method, but the first and second non-contact tangential displacement meters detect the point of contact with the virtual V-block. Can be obtained.

In order to measure the cylindricity, it is general to measure a plurality of roundness shapes along the central axis of the cylinder and to superimpose them. In the cylindrical shape measuring apparatus of the present embodiment, the roundness shape of an arbitrary cross section can be measured, and the position of the center O can be detected. The cylindrical shape is obtained by measuring the roundness shape of the cross section at the position and superimposing them.

Here, the measurement of the cylindricity when the central axis of the cylinder 1 is bent will be described. Xy, which is the straightness reference of the linear guide 42 with respect to the roundness measurement cross section
Consider a coordinate system. As shown in FIG. 7, it is assumed that the direction of the laser beam of the first tangential displacement meter is set to a direction perpendicular to the direction inclined at an angle A with respect to the x-axis of the xy coordinate system. x
If the distance from the origin of the −y coordinate system to the laser beam to be cut off is represented by L (A), the laser beam to be cut off is represented by the following equation (6).

[0040]

(Equation 6)

The direction of the laser beam of the tangential displacement meter is fixed, and L (A) is obtained from the detected value. In addition, it is represented by a polar coordinate system r (θ) with the center of the circularity shape of the cylinder as the origin, and the straight line of θ = 0 is made parallel to the X axis. As shown in FIG. 7, the center point of the roundness shape is located on the line represented by Expression (7).

[0042]

(Equation 7)

Similarly, if the direction of the laser beam of the second tangential displacement meter is set to a direction perpendicular to the direction inclined at an angle B with respect to the x-axis of the xy coordinate system, a perfect circle is similarly obtained. The center point of the degree shape is located on the line represented by Expression (8).

[0044]

(Equation 8)

The center point of the circularity shape is calculated by the equations (7) and (8).
Since the equation (7) and the equation (8) are solved simultaneously, the equation (9) is obtained. This allows
The coordinates of the center point of the roundness shape in the xy coordinate system are obtained.

[0046]

(Equation 9)

The V block measuring section 41 is connected to a linear guide 42
(By changing the z-axis direction) to determine the coordinates of the center point of the circularity shape, and by superimposing them, the axis of the cylinder can be determined. In the above embodiment, an example in which the roundness shape and the cylindricity of a cylinder having a certain diameter are measured has been described. It is desirable that a cylinder having a diameter as wide as possible can be measured with as little resetting work as possible. Hereinafter, a modified example that meets such a request will be described. FIG. 8 shows a state in which cylinders 1-A and 1-B having different diameters are placed on rollers 45 and 46 supporting the cylinder 1. When the laser beam 36 of the second tangential displacement meter is set in the direction as shown, the tangent of the small-diameter cylinder 1A in this direction is 36A, and the tangent of the large-diameter cylinder 1B is 36B. Therefore, in the case of the small diameter cylinder 1A and the large diameter cylinder 1B,
It can be seen that the displacement of the tangent position in the direction of the laser beam 36 of the second tangential displacement meter is ΔR, which is small. This is the first
The same applies to the contact type displacement meter. On the contrary,
The position of the upper tangent detected by the third tangential displacement meter is
It can be seen that a large amount ΔU changes.

When measuring cylinders having different diameters without resetting them, the first and second tangential displacement meters use a laser beam 53 having a small diameter as shown in FIG.
May be emitted. In the figure, reference numeral 54 denotes a laser diode, 55 denotes a collimator lens, 56 denotes an aperture for regulating the shape of a laser beam, 57 denotes a condenser lens, and 58 denotes a photo sensor. The aperture 56 does not need to be a circular opening, and may be an elongated slit as long as it does not cause a problem such as diffraction. If the width of the slit is large, the resolution in the cylindrical axis direction decreases.

On the other hand, the third tangential displacement meter has a large diameter laser beam 53 as shown in FIG.
Need to be emitted. In this case, the range of the diameter of the cylinder that can be measured without resetting is widened. However, FIG.
The tangential displacement meter using the laser shown in (1) and (2) has a problem that the detection accuracy of the displacement decreases as the diameter of the laser beam increases. Therefore, a third tangential displacement meter having a small diameter of the laser beam is used, and the light source unit and the light receiving unit are housed in the same housing 59 as shown in FIG. Can be moved along the moving mechanism 60, and the position is changed according to the diameter of the cylinder to be measured.

Alternatively, as shown in FIG. 9D, a large laser beam is emitted from the collimator lens 55, the aperture of the aperture 56 is made small, and the member 59 holding the aperture 56 can be moved by the moving mechanism 60. You may do so. FIG. 10 is a diagram showing a configuration of a cylindrical object shape measuring apparatus according to a second embodiment for measuring the shape of a cylindrical object in an in-process. The apparatus according to the first embodiment has a configuration dedicated to measurement, and rotates while supporting both ends of the cylindrical object 1 with rollers. In the second embodiment, the cylindrical object 1 is chucked and rotated by a rotating shaft 62 provided in a drive unit 61 of a machine tool 64 such as a lathe or a cylindrical grinder. At the time of processing, the moving member 65 provided with a cutting tool, a rotary grindstone, or the like is moved along a moving table 63 parallel to the axis of the cylinder 1 to perform the processing. In the second embodiment, the moving member has the same V as in the first embodiment shown in FIG.
The shape of the cylindrical object 1 is measured by attaching the block measuring unit 41 to the moving member 65. The measuring method is the same as in the first embodiment.

In the second embodiment, the shape of the cylinder 1 being processed can be measured without removing it from the rotating shaft 62. In FIG. 10, a moving member provided with a cutting tool or a rotating grindstone and a moving member provided with a V-block measuring unit 41 are used interchangeably. It is also possible to provide both of the moving members to which the block measuring unit 41 is attached, and perform measurement during processing.

The embodiments of the present invention have been described above.
As the first and second tangential displacement meters, non-contact types other than the optical type using a laser may be used, and a normal displacement type may be used as the third displacement meter. Furthermore, the first
The third displacement meter may use a contact type as the third displacement meter. In this case, the displacement meter only detects the displacement or the displacement of the tangent line, and it is not necessary to rotate the cylinder with the displacement meter. It is also possible to reduce the pressure so that no scratches occur.

[0053]

As described above, according to the present invention,
Since the cross-sectional shape can be measured with high accuracy by a simple process similar to the V-block method, and the setting for the measurement is easy as in the V-block method, it can be applied to in-process measurement. Further, since the position of the measurement cross section is not restricted by the V block, a cross section shape at an arbitrary cross section position can be measured, and a cylindrical shape can be measured by connecting them.

Further, unlike the V-block method, since the degree of freedom in supporting the cylindrical object is high, even if the cylindrical object is supported by an elastic member or the cylindrical mechanism is supported by a rotation mechanism having insufficient rotation accuracy, high accuracy is achieved. Measurement becomes possible. Moreover, if a non-contact type is used as the displacement meter, no damage is caused on the cylindrical object.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating measurement of a roundness shape by a three-point method and a V-block method.

FIG. 2 is a diagram illustrating measurement of a roundness shape by a conventional pseudo V-block method.

FIG. 3 is a diagram showing a basic configuration for measuring a roundness shape by the virtual V-block method of the present invention.

FIG. 4 is a diagram showing a configuration of a cylindrical external shape measuring apparatus according to the first embodiment of the present invention.

FIG. 5 is a diagram illustrating a non-contact tangential displacement meter using a laser beam used in the first embodiment.

FIG. 6 is a diagram illustrating a method of obtaining a cross-sectional shape by a V-block method and a virtual V-block method.

FIG. 7 is a diagram illustrating a method for detecting a center point of a roundness shape.

FIG. 8 is a diagram showing an arrangement when measuring cylindrical objects having different diameters in the first embodiment.

FIG. 9 is a diagram showing a modification of the non-contact tangential displacement meter using a laser beam when measuring cylinders having different diameters in the first embodiment.

FIG. 10 is a view showing a configuration of a cylindrical external shape measuring apparatus according to a second embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... DUT (cylindrical object) 4: V block 31, 34, 37, 51 ... Light source part 32, 35, 38, 52 ... Light receiving part 33, 36, 39, 53 ... Laser beam 41 ... V block measuring part 42 … Linear guide 45, 46… Roller

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Makoto Sakai 1-1-74 Akebono, Mizumicho, Nishikanbara-gun, Niigata Within Micro Technology Co., Ltd. (72) Inventor Kazuhisa Yanagi 1603-1 Kamitomiokacho, Nagaoka City, Niigata Prefecture Nagaoka Inside the College of Technology (72) Inventor Ryuichi Yamada 888 Nishikatagai-cho, Nagaoka City, Niigata Prefecture Inside Nagaoka National College of Technology (72) Inventor Atsuya Yokota 1603-1 Kamitomioka-cho, Nagaoka City, Niigata Prefecture F-term in Nagaoka University of Technology ( Reference) 2F065 AA48 BB06 BB24 DD03 DD06 FF02 GG04 GG15 HH03 HH14 JJ03 JJ05 JJ08 JJ26 MM04 MM12 MM16 MM26 NN16 PP13 QQ17 QQ21 RR05 TT02 UG02 GG02 GG07 NN19 PP02 QQ05

Claims (22)

[Claims] 1. A cylindrical shape measuring apparatus for measuring the shape of a cylindrical object to be measured, a rotating means for rotating the object to be measured about an axis, and a rotation angle of the object to be measured. Rotation angle position detecting means for detecting a position, first tangential displacement detecting means for detecting a displacement of a tangent perpendicular to a first direction of an outer shape in a predetermined cross section of the measured object, and a predetermined cross section of the measured object A second tangent displacement detecting means for detecting a displacement of a tangent line perpendicular to a second direction of the outer shape in the third step; Tangential displacement detecting means, tangential displacement perpendicular to the first to third directions detected by the first to third tangential displacement detecting means, and the object to be measured detected by the rotational angle position detecting means From the rotational angle position of the object to be measured A calculating means for calculating an outer shape at the predetermined cross section; 2. The cylindrical shape measuring apparatus according to claim 1, wherein said first to third tangential displacement detecting means are integrated and move parallel to each other along an axis of said object to be measured. An apparatus for measuring the shape of a cylindrical object comprising means. 3. The apparatus for measuring the shape of a cylindrical object according to claim 1, wherein said first to third tangential displacement detecting means does not contact a surface of said object to be measured. Non-contact type cylindrical object shape measuring device that detects the amount of tangential displacement of an object. 4. The cylindrical shape measuring apparatus according to claim 3, wherein the first to third tangential displacement detecting means include: a laser light source that emits a parallel laser beam; And a photodetector that outputs a signal corresponding to the received laser beam, wherein the device under test is arranged to block a part of the laser beam, and an output signal of the photodetector A cylindrical shape measuring device that detects the tangent position of the external shape of a measured object. 5. The cylindrical shape measuring apparatus according to claim 4, wherein said rotating means is at least one set of two rollers, and said rotating member is supported by rotating said rollers. A cylindrical shape measuring device that rotates a measuring object. 6. The apparatus for measuring the shape of a cylindrical object according to claim 5, wherein the first and second tangential displacement detecting means are arranged so that the laser beam is transmitted between the two rollers and the object to be measured. An apparatus for measuring the shape of a cylindrical object arranged to pass near a contact point. 7. The apparatus for measuring the shape of a cylindrical object according to claim 6, wherein the laser beam emitted from the laser light source of the first and second tangential displacement detecting means has a small width, and the third The laser beam emitted from the laser light source of the tangential displacement detecting means of the first aspect of the present invention is a cylindrical shape measuring apparatus having a wider width than the first and second tangential displacement detecting means. 8. The apparatus for measuring the shape of a cylindrical object according to claim 6, further comprising: a moving unit that moves the third tangential displacement detecting unit in a normal direction of the device to be measured. An apparatus for measuring the shape of a cylindrical object in which the arrangement of the second tangential displacement detecting means is fixed. 9. The apparatus for measuring a shape of a cylindrical object according to claim 6, wherein the laser beam emitted from the laser light source of the first and second tangential displacement detecting means has a small width, and the third The laser beam emitted from the laser light source of the tangential displacement detecting means is wider than the first and second tangential displacement detecting means, and the third tangential displacement detecting means emits the laser light from the laser light source. An apparatus for measuring the shape of a cylindrical object, comprising: an aperture for partially blocking the laser beam to be emitted; and a moving means for moving the aperture in a direction normal to the object to be measured. 10. The apparatus for measuring the shape of a cylindrical object according to claim 4, wherein the rotating means is a rotary shaft of a machine tool that chucks and rotates the workpiece for processing. Shape measuring device. 11. The apparatus for measuring the shape of a cylindrical object according to claim 10, wherein the rotational angle position detecting means is a rotational angle position detector for a rotary shaft of the machine tool. 12. The cylindrical shape measuring apparatus according to claim 4, wherein the first to third tangential displacement detecting means move in a normal direction of the object to be measured. Object shape measuring device. 13. The apparatus according to claim 4, wherein the first to third tangential displacement detecting means partially block the laser beam emitted from the laser light source. And a moving means for moving the aperture in a direction normal to the object to be measured. 14. A cylindrical shape measuring apparatus for measuring a shape of a cylindrical object to be measured, a rotating means for rotating the object to be measured about an axis, and a rotation angle of the object to be measured. Rotation angle position detecting means for detecting a position, first tangential displacement detecting means for detecting a displacement of a tangent perpendicular to a first direction of an outer shape in a predetermined cross section of the measured object, and a predetermined cross section of the measured object A second tangential displacement detecting means for detecting a displacement of a tangent perpendicular to a second direction of the outer shape, a displacement detecting means for detecting a displacement of the outer shape in a predetermined cross section of the object to be measured in a third direction, A rotation angle position of the object to be measured detected by rotation angle position detection means, a tangential displacement perpendicular to the first and second directions detected by the first and second tangential displacement detection means, and the displacement The third direction detected by the detection means; Calculating means for calculating the external shape of the object to be measured at the predetermined cross section from the displacement of the object. 15. A method for measuring the shape of a cylindrical object to measure the shape of a cylindrical object, the method comprising: rotating the object to be measured about an axis; and a rotation angle position of the object to be measured. Detecting a displacement of a tangent perpendicular to a first direction of an outer shape of the object to be measured in a predetermined cross section; and detecting a tangent of the outer shape of the object to be measured in a predetermined cross section perpendicular to a second direction. Detecting a displacement of the object to be measured; detecting a displacement of a tangent line perpendicular to a third direction of an outer shape of the object to be measured in a predetermined cross section; and detecting a rotation angle position of the object to be measured and the first detected position. Calculating a contour of the object to be measured at the predetermined cross section from a displacement of a tangent line perpendicular to the third direction. 16. The method for measuring a shape of a cylindrical object according to claim 15, wherein the step is performed on a plurality of predetermined cross sections of the object to be measured, and a change in an outer shape of the object to be measured in an axial direction is obtained. A method for measuring the shape of a cylindrical object for measuring the shape. 17. The method for measuring the shape of a cylindrical object according to claim 15, wherein the displacement of a tangent perpendicular to the first to third directions is detected.
A method for measuring the shape of a cylindrical object performed in a non-contact type. 18. The method for measuring a shape of a cylindrical object according to claim 17, wherein the detection of the displacement of a tangent perpendicular to the first to third directions includes: A method for measuring the shape of a cylindrical object, wherein the cylindrical portion is arranged so as to block a portion, and a tangential position of an outer shape of the object to be measured is detected by detecting the laser beam. 19. The method for measuring the shape of a cylindrical object according to claim 18, wherein the rotation of the object to be measured supports the object to be measured on at least one set of two rollers. A method for measuring the shape of a cylindrical object performed by rotating the object to be measured supported by rotating the object. 20. The method for measuring the shape of a cylindrical object according to claim 19, wherein the first and second directions are defined by a distance between the two rollers and the object to be measured from a center of the object to be measured. A method for measuring the shape of a cylindrical object in the direction toward the point of contact. 21. The method for measuring the shape of a cylindrical object according to claim 19, wherein the rotation of the object to be measured is performed by rotating a rotation axis of a machine tool that chucks and rotates the object to be processed. The method for measuring the shape of a cylindrical object performed by performing 22. A method for measuring the shape of a cylindrical object, the method comprising: measuring a shape of a cylindrical object; rotating the object about an axis; and a rotational angle position of the object. Detecting a displacement of a tangent perpendicular to a first direction of an outer shape of the object to be measured in a predetermined cross section; and detecting a tangent of the outer shape of the object to be measured in a predetermined cross section perpendicular to a second direction. Detecting a displacement of the object to be measured in a third direction in a predetermined cross section of the object to be measured; a rotational angle position of the object to be measured; and the detected first and second directions. Calculating a profile of the object to be measured at the predetermined cross section from a displacement of a tangent perpendicular to the direction and a detected displacement in the third direction.