JP6924953B2 - Shape measuring device and shape measuring method - Google Patents

Description

The present invention relates to a shape measuring device and a shape measuring method for measuring the shape of a work.

A shape measuring device for measuring various shapes such as roundness and dimensions (radius or diameter, etc.) of a cylindrical or cylindrical workpiece is known. For example, in Patent Document 1, three or more contact-type or non-contact-type rangefinders are arranged on the outer peripheral surface or inner peripheral surface (measured surface) of a cylindrical work, and the work is relative to each distance meter. A shape measuring device that detects the outer diameter or inner diameter of a work based on the result of detecting the distance to each peripheral surface with each distance meter while rotating is disclosed.

Patent Document 2 is based on the result of arranging an optical sensor at a position facing the outer peripheral surface of a cylindrical workpiece and detecting the distance to the outer peripheral surface with the optical sensor while rotating the workpiece relative to the optical sensor. , A shape measuring device for measuring the shape of the outer peripheral surface of the work is disclosed. Further, the shape measuring device of Patent Document 2 has a configuration in which an optical sensor is step-moved to a plurality of positions in the longitudinal direction of the work, and distance detection by the optical sensor is executed at each of the plurality of positions while rotating the work. Therefore, the diameter of each of a plurality of positions of the work can be detected. Thereby, the shape measuring device of Patent Document 2 can detect the cylindricity of the work.

Patent Document 3 describes a work shape (including an outer diameter) in a non-contact manner using a pair of two-dimensional laser type first displacement sensors for distance detection and a two-dimensional laser type second displacement sensor for shape measurement. ) Is disclosed.

In Patent Document 4, while rotating a disk-shaped work, a laser light source arranged on one surface side of the work irradiates a laser beam toward the circumferential edge of the work, and the laser light is applied to the work. A shape measuring device that receives light from a light receiving unit arranged on the other side of the surface is disclosed. The shape measuring device of Patent Document 4 detects the shape of the circumferential edge of the work based on the light amount distribution of the laser light received by the light receiving unit.

Japanese Unexamined Patent Publication No. 2004-045206 Japanese Unexamined Patent Publication No. 2003-057020 Japanese Unexamined Patent Publication No. 2013-007749 Japanese Unexamined Patent Publication No. 2014-052257

However, in the shape measuring devices of Patent Document 1 and Patent Document 2, it is necessary to rotate (relatively move) the work relative to the measuring unit such as the distance meter and the optical sensor. For this reason, measurement takes time due to the limitation of the rotation speed, measurement error occurs due to vibration during rotation, position adjustment (centering) of the work is required, and the device becomes complicated by providing a rotation mechanism. In addition, problems such as difficulty in measuring the shape of a workpiece that is difficult to rotate or fix occur.

In the shape measuring device of Patent Document 3, for example, the inner diameter of a cylindrical work cannot be measured because the work is irradiated with a laser beam from a large two-dimensional laser displacement sensor arranged outside the work. .. Further, also in the shape measuring device described in Patent Document 3, since it is necessary to rotate the work relative to the two-dimensional laser type displacement sensor, the same problem as the shape measuring device in Patent Document 1 and Patent Document 2 occurs. be.

The measuring device of Patent Document 4 has a problem that only the circumferential edge of a disk-shaped work can be measured. Further, the measuring device of Patent Document 4 also has the same problem as the measuring devices of Patent Document 1 and Patent Document 2 because it is necessary to rotate the work.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide a shape measuring device and a shape measuring method capable of measuring the shape of a work with high accuracy and high speed.

The shape measuring device for achieving the object of the present invention is provided for each reference position set at 3 or more on the same circumference centered on the reference plane on which the work is placed and the measurement reference axis perpendicular to the reference plane. , The distance detection unit that detects the distance from the reference position to the measurement point in the measurement plane of the workpiece facing the reference position, the known position information of each reference position with respect to the measurement reference axis, and the distance detection unit detected. It is provided with an analysis unit that obtains the shape of the work based on the distance for each reference position.

According to this shape measuring device, the shape of the work is measured by detecting the distance from each reference position to the measurement point in the surface to be measured of the work facing each other without rotating (moving) the work. Can be done.

In the shape measuring device according to another aspect of the present invention, the reference positions are set at equal angular intervals on the same circumference with the measurement reference axis as the center. As a result, the positions of the measurement points in the surface to be measured can be acquired at equal intervals, so that the shape of the work can be measured with high accuracy regardless of the position, posture, and type (shape) of the work.

The shape measuring device according to another aspect of the present invention includes a repetitive control unit that repeatedly operates the distance detection unit and the analysis unit a plurality of times, and the analysis unit obtains an average shape obtained by averaging the shapes of the workpieces obtained a plurality of times. .. As a result, the influence of the error of distance detection is reduced, so that the shape of the work can be measured with high accuracy.

In the shape measuring device according to another aspect of the present invention, for each reference position, a signal is incident on a measurement point facing the reference position from the reference position, and the reflected signal is individually detected for each measurement point. The distance detection unit detects the distance for each reference position based on the signal detection result for each measurement point by the measurement unit. As a result, the distance for each reference position can be detected in a non-contact manner without rotating (moving) the work.

In the shape measuring apparatus according to another aspect of the present invention, the signal is measurement light, and the direction of the optical axis of the measurement light incident on the measurement point from the reference position is measured in the plane including the reference position and the measurement reference axis. The direction is perpendicular to the reference axis. As a result, the shape of the work can be measured with high accuracy with reference to the measurement reference axis.

In the shape measuring device according to another aspect of the present invention, when the work is cylindrical or cylindrical and the surface to be measured is the outer peripheral surface of the work, the reference position is set to the outside of the outer peripheral surface. Thereby, the shape of the outer peripheral surface of the work can be measured.

In the shape measuring device according to another aspect of the present invention, when the work is cylindrical and the surface to be measured is the inner peripheral surface of the work, the reference position is set inside the inner peripheral surface. Thereby, the shape of the inner peripheral surface of the work can be measured.

In the shape measuring device according to another aspect of the present invention, when the work is cylindrical and the surface to be measured is the inner peripheral surface of the work, the reference position is 3 on the same circumference inside the inner peripheral surface. As described above, the measuring unit is a plurality of reflectors individually provided for each reference position and a plurality of optical units arranged at intervals in the direction perpendicular to the reference plane, and has the same circle. It is provided with a plurality of optical units individually arranged on the circumference and at positions facing the individual reflectors, and for each optical unit, the measurement light is emitted to the reflector facing the optical unit and the optical unit is equipped with the measurement light. The measurement light incident from the opposing reflector is detected, and the measurement light incident from the optical unit facing the reflector is reflected for each reflector and incident on the measurement point facing the reflector to make the measurement point incident on the measurement point. The measurement light reflected in the above is reflected toward the optical unit facing the reflector, and the distance detection unit uses the reference position, the size of the known distance between the optical units, and the detection result of the measurement light for each optical unit. Based on the above, the distance for each reference position is detected. Thereby, even when the diameter of the inner peripheral surface of the work is small, the shape of the inner peripheral surface can be measured.

In the shape measuring device according to another aspect of the present invention, when the work has a peripheral surface and the surface to be measured is the peripheral surface, the analysis unit determines that the work is based on the position information and the distance for each reference position. As the shape, the radius of the peripheral surface and the roundness of the peripheral surface are obtained. As a result, the radius of the peripheral surface and the roundness of the peripheral surface can be measured as the shape of the work.

In the shape measuring device according to another aspect of the present invention, three or more reference positions are set on the same circumference having different axial positions of the measurement reference axes, and the distance detection unit is set for each reference position. Detect the distance. The shape of the work can be detected at different axial positions of the measurement reference axes.

In the shape measuring device according to another aspect of the present invention, when the work is cylindrical or cylindrical and the surface to be measured is at least one peripheral surface of the outer peripheral surface and the inner peripheral surface of the work, the analysis unit is positioned. Based on the information and the distance for each reference position detected by the distance detection unit, the center position of the peripheral surface is obtained for each axial position, and based on the center position for each axial position, the shape of the work is relative to the measurement reference axis. Find the tilt angle of the work. As a result, the inclination angle of the work with respect to the measurement reference axis (reference plane) can be measured as the shape of the work.

In the shape measuring apparatus according to another aspect of the present invention, when the work is cylindrical or cylindrical and the surface to be measured is at least one peripheral surface of the outer peripheral surface and the inner peripheral surface of the work, the analysis unit is positioned. Based on the information and the distance for each reference position detected by the distance detection unit, the radius of the peripheral surface is obtained for each axial position, and the straightness and cylindricity are calculated as the shape of the work based on the radius for each axial position. Ask. Thereby, the straightness and the cylindricity can be measured as the shape of the work.

The shape measuring method for achieving the object of the present invention is a shape measuring method for measuring the shape of a work placed on a reference plane on the same circumference centered on a measurement reference axis perpendicular to the reference plane. For each reference position set above, a distance detection step for detecting the distance from the reference position to the measurement point in the measured surface of the workpiece facing the reference position, and known position information of each reference position with respect to the measurement reference axis. And an analysis step of obtaining the shape of the work based on the distance for each reference position detected in the distance detection step.

The shape measuring device and the shape measuring method of the present invention can measure the shape of a work with high accuracy and high speed.

It is the schematic of the shape measuring apparatus of 1st Embodiment. It is the top view and the side view of the sensor head arranged on the reference plane. It is explanatory drawing which showed the emission direction of the measurement light emitted from each sensor head. It is a graph which showed an example of the detection result of the distance for each sensor head. It is a block diagram which shows the structure of a computer. It is explanatory drawing for demonstrating the calculation of the shape of the work by the analysis part. It is a graph which showed the relationship between the measurement accuracy of the shape (diameter of the outer peripheral surface) of a work, and the number of channels of a sensor head. It is a graph which showed the relationship between the measurement accuracy of the average shape (diameter of the outer peripheral surface) of a work, and the number of repetitions. It is a flowchart which shows the flow of shape measurement of a workpiece by a shape measuring apparatus. It is the top view and the side view of the sensor head provided in the shape measuring apparatus of 2nd Embodiment. It is explanatory drawing for demonstrating the combination of 1st Embodiment and 2nd Embodiment. It is sectional drawing of the stage and the like of the 3rd Embodiment. It is a top view of the reference plane of the 3rd Embodiment. It is a front view which looked at each sensor head in FIG. 12 from the lower side in the Z-axis direction. It is a side view of the stage and the sensor head which constitute the shape measuring apparatus of 4th Embodiment. FIG. 15 is a cross-sectional view taken along the line 16A-16A and a cross-sectional view taken along the line 16B-16B in FIG. It is explanatory drawing for demonstrating the center coordinate of the 1st measurement cross section and the center coordinate of the 2nd measurement cross section used for the calculation of the inclination of the central axis of a work. It is explanatory drawing for demonstrating the inclination calculation of the central axis of a work. It is explanatory drawing for demonstrating the modification of 4th Embodiment. It is a side view of the stage and the sensor head which constitute the shape measuring apparatus of 5th Embodiment. FIG. 20 is a cross-sectional view taken along line 21A-21A, a cross-sectional view taken along line 21B-21B, and a cross-sectional view taken along line 21C-21C.

[Shape measuring device of the first embodiment]
FIG. 1 is a schematic view of the shape measuring device 10 of the first embodiment. The shape measuring device 10 measures the shape of the cylindrical work W. The shape of the work W referred to here includes dimensions such as the diameter (radius and diameter) of the peripheral surface of the work W, the roundness of the work W, the inclination of the work W (fourth embodiment), and the work. Includes various shapes and dimensions, including straightness and cylindricity of W (fifth embodiment).

As shown in FIG. 1, the shape measuring device 10 includes a disk-shaped (other shapes are also possible) stage 12, a multi-channel non-contact displacement meter 13, and a computer 14.

The upper surface (horizontal plane) of the stage 12 is a reference plane 12a on which the work W is placed. Further, in the present embodiment, the axis passing through the center of the reference plane 12a (which may be other than the center) and perpendicular to the reference plane 12a is the measurement reference axis A1. In the figure, the central axis of the work W coincides with the measurement reference axis A1, but the central axis of the work W may be eccentric with respect to the measurement reference axis A1. That is, it is not necessary to center the work W on the reference plane 12a.

The non-contact displacement meter 13 corresponds to the measuring unit of the present invention, and includes an 8-channel (CH1 to CH8) sensor head 18, eight sensor position adjusting units 19, and a displacement meter main body 20. .. If the number of the sensor head 18 and the sensor position adjusting unit 19 (reference position P1 described later) is 3 or more, the number may be increased or decreased as appropriate.

FIG. 2 is a top view (upper row) and a side view (lower row) of the sensor head 18 arranged on the reference plane 12a. As shown in FIG. 2, an outer peripheral surface is provided at a position outside the outer peripheral surface (corresponding to the surface to be measured of the present invention) of the work W placed on the reference plane 12a and facing the outer peripheral surface. Eight reference positions P1 are preset on the same circumference (C1) with the measurement reference axis A1 as the center at equal angle intervals (45 °) so as to surround the measurement reference axis A1. Specifically, the reference position P1 is an angular position on the same circumference (C1) represented by θi = (i-1) × (360/8) [i = 1 to 8] with the measurement reference axis A1 as the center. It is set to (0 °, 45 °, 90 °, 135 °, 180 °, 225 °, 270 °, 315 °), respectively.

For the 8-channel sensor head 18, for example, a fiber collimator is used. Each sensor head 18 is connected to the displacement meter main body 20 via a signal propagation cable (optical fiber cable) (not shown). Each sensor head 18 individually emits the measurement light L (corresponding to the signal of the present invention) input from the displacement meter main body 20 toward the work W. Further, each sensor head 18 individually receives the measurement light L reflected by the work W and outputs the measurement light L individually to the displacement meter main body 20.

Each sensor position adjusting unit 19 is provided at a position corresponding to each reference position P1 on the reference plane 12a. Each sensor position adjusting unit 19 supports one sensor head 18 at the reference position P1. As a result, the 8-channel sensor heads 18 are arranged at the above-mentioned reference positions P1, that is, arranged at equal angular intervals (equal angle positions) on the same circumference (C1) about the measurement reference axis A1.

Further, each sensor position adjusting unit 19 adjusts the position of the supporting sensor head 18 in the three axial directions and adjusts the posture (pan / tilt adjustment) to adjust the measurement light L emitted from the sensor head 18. The emission direction can be adjusted arbitrarily.

FIG. 3 is an explanatory diagram showing the emission direction of the measurement light L emitted from each sensor head 18. As shown in FIG. 3, each sensor position adjusting unit 19 adjusts the position and orientation of the supporting sensor head 18, and uses the direction of the optical axis OA of the measurement light L emitted from the sensor head 18 as a reference. The direction D perpendicular to the measurement reference axis A1 is adjusted in the surface F including the position P1 and the measurement reference axis A1. As a result, the measurement light L parallel to the direction D is emitted from the sensor head 18 at each reference position P1 toward the measurement reference axis A1. As a result, the measurement light L individually emitted from each sensor head 18 (reference position P1) is individually incident on the measurement point P2 in the outer peripheral surface of the work W facing each sensor head 18 (reference position P1). (See Fig. 2).

Since the position adjustment and the posture adjustment of the sensor head 18 for each sensor position adjusting unit 19 are performed using known jigs, methods, measuring instruments, and the like, specific description thereof will be omitted here.

Returning to FIGS. 1 and 2, the measurement light L incident on the measurement points P2 facing each other from each sensor head 18 (reference position P1) is reflected toward the original sensor head 18 at each measurement point P2. , Each sensor head 18 receives light individually. As described above, the measurement light L received by each sensor head 18 is individually input to the displacement meter main body 20 via a signal propagation cable (not shown).

Under the control of the computer 14, the displacement meter main body 20 individually inputs the measurement light L to each sensor head 18 via a signal propagation cable (not shown), and receives the measurement light L received by each sensor head 18. Are individually detected (photoelectric conversion). Then, the displacement meter main body 20 is the distance from each sensor head 18 (reference position P1) to the measurement point P2 facing each other based on the detection result of the measurement light L detected for each sensor head 18 (hereinafter, simply "sensor". (Abbreviated as "distance for each head 18") is detected. That is, the displacement meter main body 20 functions as the distance detection unit of the present invention. Since a specific distance detection method is a known technique, a specific description thereof will be omitted here.

FIG. 4 is a graph showing an example of the detection result of the distance for each sensor head 18. The horizontal axis in the figure is the angular position of the sensor head 18 of 8 channels (CH1 to CH8) centered on the measurement reference axis A1.

In an ideal state where the cross-sectional shape of the outer peripheral surface of the work W in the XY axis direction is a perfect circle and the central axis of the work W coincides with the measurement reference axis A1, the distance for each sensor head 18 (reference position P1) is It will be almost the same value. However, the cross-sectional shape of the work W does not become a perfect circle due to a machining error, and in the present embodiment, the shape of the work W is detected without centering to match the central axis of the work W with the measurement reference axis A1. Since it can be done, it is not centered. Therefore, as shown in FIG. 4, the sensor head 18 (reference position P1) depends on the roundness of the work W and the eccentricity (eccentric direction and eccentricity) of the central axis of the work W with respect to the measurement reference axis A1. ) Will vary.

The displacement meter main body 20 outputs a distance detection signal indicating a distance detection result for each sensor head 18 to the computer 14.

The displacement meter main body 20 and the display unit 14a are connected to the computer 14. The computer 14 controls the operation of the displacement meter main body 20. Further, the computer 14 measures the shape of the work W based on the distance detection signal for each sensor head 18 input from the displacement meter main body 20, and displays the measurement result on the display unit 14a. In addition, various arithmetic processing units may be used instead of the computer 14.

[Computer configuration]
FIG. 5 is a block diagram showing the configuration of the computer 14. As shown in FIG. 5, the computer 14 has a control unit 25 and a storage unit 26. Although not shown, the control unit 25 is composed of various arithmetic units including a CPU (Central Processing Unit) or an FPGA (field-programmable gate array), a processing unit, a memory, and the like. The control unit 25 functions as a measurement control unit 28, an analysis unit 29, and a repetition control unit 30 by executing a control program (not shown) read from the memory or the storage unit 26.

The storage unit 26 stores the measurement result of the shape of the work W input from the analysis unit 29, which will be described later. Further, the storage unit 26 stores in advance position information 32 indicating the position of each sensor head 18 (reference position P1) with respect to the measurement reference axis A1. The position information 32 includes, for example, the angular position of each sensor head 18 (reference position P1) on the same circumference (C1) described above and the radius of the “circumference” on the same circumference (C1). ,It is included. The position information 32 is not particularly limited as long as the position of each sensor head 18 (reference position P1) can be determined with reference to the measurement reference axis A1. For example, the position information 32 is based on an arbitrary origin of the reference plane 12a. It may be the position coordinates of the measurement reference axis A1 and each sensor head 18 (reference position P1).

The measurement control unit 28 acquires a distance detection signal for each sensor head 18 by the displacement meter main body 20 (emission of measurement light L from each sensor head 18, detection of measurement light L received by each sensor head 18, and sensor head). (Detection of distance for each 18) is controlled. Further, the measurement control unit 28 outputs the distance detection signal for each sensor head 18 acquired from the displacement meter main body 20 to the analysis unit 29.

The analysis unit 29 obtains the shape of the work W based on the distance detection signal for each sensor head 18 acquired from the displacement meter main body 20 and the above-mentioned position information 32 acquired from the storage unit 26. In the present embodiment, the radius (diameter) and roundness of the outer peripheral surface of the work W are obtained as the shape of the work W.

FIG. 6 is an explanatory diagram for explaining the calculation (analysis) of the shape of the work W by the analysis unit 29. The analysis unit 29 can determine the distance for each sensor head 18 based on the distance detection signal for each sensor head 18. Further, the analysis unit 29 discriminates between the angular position of each sensor head 18 (reference position P1) with respect to the measurement reference axis A1 and the radius of the “circumference” on the same circumference (C1) based on the position information 32. can.

Therefore, as shown by the “dotted line” in FIG. 6, the analysis unit 29 has the outer peripheral surface of the work W placed on the reference plane 12a based on the distance detection signal and the position information 32 for each sensor head 18. The position of each measurement point P2 (position with reference to the measurement reference axis A1) can be detected. As a result, the analysis unit 29 _{can obtain the center coordinates (x 0} , y ₀ ) of the work W and the radius R of the outer peripheral surface of the work W.

For example, the number of sensor heads 18 (reference position P1) is set to "N" (N = 8 in this embodiment). Further, as shown in the following Expression 1, the distance to the measurement point P2 of each sensor head 18 with the "r _i", the angular position of each sensor head 18 and "theta _i". Thus, the position of each measurement point P2 in the outer peripheral surface of the workpiece W can be expressed by polar coordinates (r _i, θ _i). Then, the analysis unit 29, the polar coordinate values of the measurement point P2 a _{(r i,} θ _i), using the Equation 2 formula, coordinate conversion into coordinate values of the XY coordinate system _(x i, _{y i)} do.

Subsequently, analyzing unit 29, based on the coordinate values of the measurement points P2 converted into the XY coordinate system (x _{i, y i),} using the equations shown in Equation 3 the following formula, of the workpiece W center coordinates ( x ₀ , y ₀ ) and the radius R of the outer peripheral surface of the work W are calculated.

_{Based on the center coordinates (x 0} , y ₀ ) of the work W obtained as described above, the eccentricity (eccentric direction and eccentric amount) of the center axis of the work W with respect to the measurement reference axis A1 can be obtained. Therefore, the analysis unit 29 corrects the eccentricity of the central axis of the work W with respect to the measurement reference axis A1 in the same manner as in the case of obtaining the roundness of the work W by the known least squares center method. Specifically, as shown in the following equation [Equation 4], the analysis unit 29 uses the coordinate values (x _i , y _i ) of _{each measurement point P2 using the center coordinates (x 0} , y _{0) of the work W.} Is corrected, and the corrected coordinate values (xa _i , ya _i ) of each measurement point P2 are calculated. As a result, as shown by the “solid line” in the figure, the position of each measurement point P2 after eccentricity correction with respect to the measurement reference axis A1 is calculated.

Next, the analysis unit 29 _{, based on the correction coordinate values (xa i} , ya _i ) of each measurement point P2, from the measurement reference axis A1 (origin) to each measurement point P2 as shown by the following equation [Equation 5]. and calculates the distance ra _i, respectively. Then, the analysis unit 29, the calculation result of the distance ra _i to each measurement point P2, based on the radius R previously calculated, using the number 6] the following equation, for each measurement point P2 with respect to the radius R Calculate the variation δ _i of the distance ra _{i. Since the variation δ i} for each measurement point P2 is a value that serves as an index of the roundness of the outer peripheral surface of the work W, the roundness of the outer peripheral surface of the work W (simple roundness) is based on _{each variation δ i.} Is required. The roundness may be calculated by using a known method such as the above-mentioned least squares center method.

In this way, the analysis unit 29 can obtain the radius R (diameter) and roundness of the outer peripheral surface of the work W as the shape of the work W based on the distance detection signal and the position information 32 for each sensor head 18. can. As a result, one work W shape measurement is completed. The analysis unit 29 outputs the measurement result of the shape of the work W [measurement result of radius R (diameter) and roundness] to the display unit 14a and the storage unit 26.

FIG. 7 is a graph showing the relationship between the measurement accuracy of the shape of the work W (diameter of the outer peripheral surface) and the number of channels of the sensor head 18. Here, assuming that each sensor head 18 has a measurement error (detection error) of ± 0.1 μm, 500 simulations are performed to determine the variation in the diameter of the outer peripheral surface and the 2σ deviation for each number of channels. I'm looking for it.

As shown in FIG. 7, the variation in diameter is about 0.33 μm when the number of channels is the minimum number “3”, and gradually decreases as the number of channels increases. Further, the 2σ deviation of the diameter is also about 0.30 μm when the number of channels is the minimum number “3”, and gradually decreases as the number of channels increases. Therefore, even if there is a measurement error of ± 0.1 μm for each sensor head 18, the measurement result of the distance for each sensor head 18 is averaged by performing the measurement with multiple channels, and the variation and the 2σ deviation are reduced. be able to. As a result, the shape of the work W can be measured with high accuracy.

Returning to FIG. 5, the repeat control unit 30 repeatedly operates the measurement control unit 28 (displacement meter main body 20) and the analysis unit 29 a plurality of times. As a result, the acquisition of the distance detection signal for each sensor head 18 by the displacement meter main body 20 and the measurement control unit 28 and the calculation of the shape of the work W by the analysis unit 29 are repeated a plurality of times. The number of repetitions can be set to a desired number by the user. As a result, the detection result of the shape of the work W for a plurality of times can be obtained.

The analysis unit 29 repeatedly calculates the shape of the work W a plurality of times, and then uses the average value of the radius R (diameter) of the outer peripheral surface of the work W as the average shape obtained by averaging the shapes of the work W obtained a plurality of times. Calculate the average value of roundness. Then, the analysis unit 29 outputs the calculated average shape result of the work W to the display unit 14a and stores it in the storage unit 26.

FIG. 8 is a graph showing the relationship between the measurement accuracy of the average shape (diameter of the outer peripheral surface) of the work W and the number of repetitions. Here, assuming that there is a measurement error of ± 0.1 μm for each sensor head 18, the outer peripheral surface for each number of repetitions is performed by performing 500 simulations under the condition of using the 8-channel sensor head 18. The variation in diameter and the deviation of 2σ were obtained. Assuming that the time required for one measurement is about 1 msec, the time required for 100 repetitions is about 100 msec.

As shown in FIG. 8, as the number of repetitions increases, the variation in diameter of the outer peripheral surface of the work W and the 2σ deviation decrease. Therefore, even if there is a measurement error of ± 0.1 μm for each sensor head 18, the shape of the work W is repeatedly measured a plurality of times to calculate the average shape of the work W, thereby causing a non-contact displacement meter. The influence of the measurement error of 13 can be reduced.

[Operation of the shape measuring device of the first embodiment]
FIG. 9 is a flowchart showing a flow of shape measurement of the work W by the shape measuring device 10 having the above configuration (shape measuring method of the present invention). The setting of each reference position P1, the adjustment of the position and orientation of each sensor head 18, and the calibration of the non-contact displacement meter 13 are performed in advance. As shown in FIG. 9, the user first places the work W to be measured on the reference plane 12a (step S1). At this time, since it is not necessary to perform centering so that the central axis of the work W is aligned with the measurement reference axis A1, the measurement time can be shortened.

Next, when the user performs the measurement start operation on the computer 14, the measurement light L is input from the displacement meter main body 20 to each sensor head 18 under the control of the measurement control unit 28 of the control unit 25, and the measurement light L is input from each sensor head 18. The measurement light L is individually emitted toward the measurement point P2 in the outer peripheral surface of the work W facing each other. Then, each sensor head 18 individually receives the measurement light L reflected at the measurement points P2 facing each other (step S2). As a result, the measurement light L received by each sensor head 18 is individually input to the displacement meter main body 20.

Next, in the displacement meter main body 20, the detection of the measurement light L for each sensor head 18 and the detection of the distance for each sensor head 18 are sequentially executed, and then the displacement meter main body 20 sends the sensor head to the measurement control unit 28. A distance detection signal for each of 18 is output (step S3, corresponding to the distance detection step of the present invention). The time required for one measurement is 1 to 10 msec. As a result, the distance detection signal for each sensor head 18 is input to the measurement control unit 28, and further input to the analysis unit 29 via the measurement control unit 28.

The analysis unit 29, which has received the input of the distance detection signal for each sensor head 18, uses the above equations [Equation 1] to [Equation 6] based on each distance detection signal and the position information 32 acquired from the storage unit 26. The shape of the work W [radius R (diameter) and roundness of the outer peripheral surface] is calculated using the work (step S4, corresponding to the analysis step of the present invention). As a result, the first shape measurement of the work W is completed, and the measurement result is output from the analysis unit 29 to the display unit 14a and the storage unit 26, respectively.

At this time, in the present embodiment, since the shape of the work W is measured using the 8-channel sensor head 18, the detection results for each sensor head 18 are averaged as shown in FIG. 7 described above. The variation and the 2σ deviation can be reduced. As a result, the shape of the work W can be measured with high accuracy.

Next, the repeat control unit 30 repeatedly operates the measurement control unit 28 (displacement meter main body 20) and the analysis unit 29 when the number of repetitions of shape measurement has not reached a preset number of times set by the user. The processing from step S2 to step S4 described above is executed again (NO in step S5). As a result, the shape of the work W is recalculated by the analysis unit 29.

Hereinafter, the processes from step S2 to step S5 described above are executed until the number of repetitions reaches the set number of times (YES in step S5). As a result, the measurement result of the shape of the work W for a plurality of times can be obtained. Next, the analysis unit 29 calculates an average shape obtained by averaging the shapes of the work W for a plurality of times, outputs the calculation result to the display unit 14a, and stores the calculation result in the storage unit 26 (step S6). By repeatedly executing the shape measurement a plurality of times in this way to obtain the average shape of the work W, the influence of the measurement error for each sensor head 18 is reduced, and as shown in FIG. 8 described above, the shape detection result is obtained. The variation and 2σ deviation can be reduced. As a result, the shape of the work W can be measured with high accuracy.

[Effect of the first embodiment]
As described above, in the shape measuring device 10 of the first embodiment, by using the non-contact displacement meter 13, from each sensor head 18 (reference position P1) to the measurement point P2 on the outer peripheral surface of the work W facing each other. Distance can be detected collectively without contact. As a result, the shape of the work W can be measured without rotating the work W relative to the sensor head 18 as in the conventional case. Therefore, the shortening of the measurement time, and prevention of measurement errors due to vibration during rotation, and simplification of the apparatus construction due to omission of the rotary mechanism, that enables the shape measurement of the rotational or fixed hard workpiece W The effect is obtained. As a result, the shape of the work W can be measured with high accuracy and high speed.

[Shape measuring device of the second embodiment]
FIG. 10 is a top view (upper row) and a side view (lower row) of the sensor head 18 provided in the shape measuring device 10 of the second embodiment. In the first embodiment, the radius R (diameter) and roundness of the outer peripheral surface of the work W are measured as the shape of the cylindrical work W, but in the shape measuring device 10 of the second embodiment, the work The radius R (diameter) and roundness of the inner peripheral surface of W (corresponding to the surface to be measured of the present invention) are measured.

The shape measuring device 10 of the second embodiment has basically the same configuration as the shape measuring device 10 of the first embodiment except that the arrangement of the sensor heads 18 is different. Those having the same function or configuration as the above are designated by the same reference numerals and the description thereof will be omitted.

As shown in FIG. 10, in the second embodiment, the same circle is formed inside the inner peripheral surface (position facing the inner peripheral surface) of the work W placed on the reference plane 12a with the measurement reference axis A1 as the center. Eight reference positions P1 are preset on the circumference (C2) at equal angular intervals (45 °). That is, in the second embodiment, eight reference positions P1 are set inside the inner peripheral surface of the work W in an arrangement pattern similar to that of the first embodiment. As a result, the 8-channel sensor heads 18 are arranged at equal angular intervals on the same circumference (C2) with the measurement reference axis A1 as the center.

Each sensor position adjusting unit 19 of the second embodiment adjusts the position and orientation of the sensor head 18 that supports the sensor head 18, and the optical axis of the measurement light L emitted from the sensor head 18 as in the first embodiment. Adjust the direction of OA to direction D (see FIG. 3). As a result, the measurement light L is radially emitted from the sensor head 18 at each reference position P1 about the measurement reference axis A1. As a result, the measurement light L individually emitted from each sensor head 18 (reference position P1) is individually directed to the measurement point P2 in the inner peripheral surface of the work W facing each sensor head 18 (reference position P1). Incident.

Further, each sensor head 18 individually receives the measurement light L reflected at the measurement points P2 facing each other. Then, the measurement light L received by each sensor head 18 is individually input to the displacement meter main body 20.

Similar to the first embodiment, the displacement meter main body 20 of the second embodiment detects the measurement light L for each sensor head 18 and detects the distance for each sensor head 18. As a result, the distances from each sensor head 18 (reference position P1) to the measurement point P2 in the inner peripheral surface of the work W facing each other are detected. Then, the displacement meter main body 20 outputs a distance detection signal for each sensor head 18 to the computer 14.

The computer 14 of the second embodiment is based on the distance detection signal for each sensor head 18 input from the displacement meter main body 20 and the position information 32 acquired from the storage unit 26, as in the first embodiment. The radius R (diameter) and roundness of the inner peripheral surface of the work W are obtained from the equation 1] to the equation [Equation 6].

Since the operation of the shape measuring device 10 of the second embodiment is basically the same as that of the first embodiment shown in FIG. 9 described above, a specific description thereof will be omitted here. Then, according to the shape measuring device 10 of the second embodiment, the distances from each sensor head 18 (reference position P1) to the measuring point P2 in the inner peripheral surface of the work W facing each other are collectively non-contact. Since it can be detected, the same effect as that of the first embodiment can be obtained.

[Combination of 1st Embodiment and 2nd embodiment]
FIG. 11 is an explanatory diagram for explaining a combination of the first embodiment and the second embodiment. As shown in FIG. 11, the reference positions P1 are set on the outside of the outer peripheral surface of the work W and the inside of the inner peripheral surface of the work W by combining the first embodiment and the second embodiment, and each reference is set. The sensor head 18 may be arranged at the position P1. As a result, the shapes of the outer peripheral surface and the inner peripheral surface of the work W can be measured collectively.

[Shape measuring device of the third embodiment]
Next, the shape measuring device 10 according to the third embodiment of the present invention will be described. In the second embodiment, each sensor head 18 and each sensor position adjusting unit 19 are arranged inside the inner peripheral surface of the work W, but when the diameter of the inner peripheral surface of the work W is small, each sensor The head 18 and the like cannot be arranged inside the inner peripheral surface of the work W. Therefore, the shape measuring device 10 of the third embodiment measures the shape of the inner peripheral surface of the work W without arranging the sensor heads 18 and the like inside the inner peripheral surface of the work W.

The shape measuring device 10 of the third embodiment has the above-mentioned third embodiment except that the arrangement of the sensor heads 18 is different and the reflector 35 (see FIG. 12) is provided instead of the sensor position adjusting unit 19. The configuration is basically the same as that of the shape measuring device 10 of the second embodiment. Therefore, those having the same function or configuration as each of the above embodiments are designated by the same reference numerals and the description thereof will be omitted.

FIG. 12 is a cross-sectional view of the stage 12 and the like according to the third embodiment. FIG. 13 is a top view of the reference plane 12a of the third embodiment. FIG. 14 is a front view (bottom view) of each sensor head 18 in FIG. 12 as viewed from the lower side in the Z-axis direction.

As shown in FIGS. 12 to 14, a substantially disk-shaped reflector holding portion 36 is provided in a region on the reference plane 12a and inside the inner peripheral surface of the work W. A reflector 35 is provided on the upper surface of the reflector holding portion 36 for each of the above-mentioned reference positions P1. As a result, the eight reflectors 35 are arranged at equal angular intervals on the same circumference (C2) with the measurement reference axis A1 as the center.

For each reflector 35, for example, a mirror is used. Each reflector 35 reflects the measurement light L incident from above in the Z-axis direction in a direction parallel to the direction D (see FIG. 3) and toward the inner peripheral surface of the work W. As a result, the measurement light L incident from above in the Z-axis direction is reflected toward the measurement point P2 in the inner peripheral surface of the work W facing each reflector 35 (reference position P1). Further, each reflector 35 reflects the measurement light L incident from the measurement point P2 facing each other toward the upper side in the Z-axis direction.

Each sensor head 18 of the third embodiment corresponds to the optical unit of the present invention, and is arranged at intervals in the direction perpendicular to the reference plane 12a (upper in the Z-axis direction). Specifically, a disk-shaped sensor holding portion 37 parallel to the reference plane 12a is supported by a support portion (not shown) at a position above the reference plane 12a and facing each reflector 35. There is. On the lower surface of the sensor holding portion 37, a sensor head 18 is provided at a position facing each reference position P1 (each reflector 35).

Each sensor head 18 emits the measurement light L downward in the Z-axis direction. As a result, the measurement light L is emitted from each sensor head 18 toward the reflector 35 (reference position P1) facing each other. Then, each measurement light L is radially reflected by each reflector 35 toward the measurement point P2 facing each other.

Next, the measurement light L individually incident on each measurement point P2 is individually reflected toward the original reflector 35 at each measurement point P2. The measurement light L incident on the reflector 35 facing each other from each measurement point P2 is individually reflected by each reflector 35 toward the sensor head 18 facing each other. As a result, each sensor head 18 individually receives the measurement light L reflected by the reflector 35 facing each other. Hereinafter, as in each of the above embodiments, the measurement light L received by each sensor head 18 is individually input to the displacement meter main body 20.

The displacement meter main body 20 of the third embodiment individually detects the measurement light L received by each sensor head 18. Next, the displacement meter main body 20 uses the sensor based on the detection result of the measurement light L detected for each sensor head 18 and the size (reference numeral α) of the known distance (distance) between the reference position P1 and the sensor head 18. For each head 18, the distance from the reflector 35 (reference position P1) to the measurement point P2 facing the reflector 35 is detected.

For example, the displacement meter main body 20 detects the optical path length of each measurement light L based on the detection result of the measurement light L for each sensor head 18, and subtracts the value of the above interval from each detected optical path length to refer to the reference. The distance to the measurement point P2 is detected for each position P1. Then, the displacement meter main body 20 outputs a distance detection signal for each sensor head 18 to the computer 14.

Since the subsequent processing is basically the same as that of the second embodiment, specific description thereof will be omitted.

As described above, in the shape measuring device 10 of the third embodiment, the optical path of the measurement light L is refracted by using the reflectors 35 arranged at the reference positions P1 to be inside the inner peripheral surface of the work W. The shape of the inner peripheral surface of the work W can be measured without arranging each sensor head 18 and each sensor position adjusting unit 19 in the work W. Thereby, even when the diameter of the inner peripheral surface of the work W is small, the shape of the inner peripheral surface can be measured. Moreover, the same effect as each of the above-described embodiments can be obtained.

[Shape measuring device of the fourth embodiment]
Next, the shape measuring device 10 according to the fourth embodiment of the present invention will be described. In each of the above embodiments, the radius R (diameter) and roundness of the inner and outer peripheral surfaces of the work W are measured as the shape of the work W, but in the fourth embodiment, the inclination of the work W with respect to the measurement reference axis A1. Measure the angle. Here, the inclination angle of the work W is an inclination angle of the central axis A2 (see FIG. 15) of the work W with respect to the measurement reference axis A1.

FIG. 15 is a side view of the stage 12 and the sensor head 18 constituting the shape measuring device 10 of the fourth embodiment. 16 is a cross-sectional view taken along line 16A-16A in FIG. 15 (upper row) and a cross-sectional view taken along line 16B-16B in FIG. 15 (lower row). The shape measuring device 10 of the fourth embodiment has basically the same configuration as the shape measuring device 10 of the first embodiment, except that it includes two sets of 8-channel sensor heads 18. Therefore, those having the same function or configuration as the first embodiment are designated by the same reference numerals and the description thereof will be omitted.

As shown in FIGS. 15 and 16, in the fourth embodiment, the measurement reference shaft is outside the outer periphery of both the first measurement cross section CS1 and the second measurement cross section CS2 of the work W perpendicular to the measurement reference axis A1. Eight reference positions P1 are preset on the same circumference (C1) with A1 as the center at equal angular intervals. The first measurement cross section CS1 and the second measurement cross section CS2 have different axial positions of the measurement reference axis A1. The height h of the first measurement cross section CS1 with reference to the second measurement cross section CS2 is a known value.

Each sensor head 18 of the fourth embodiment is arranged and supported at each reference position P1 by a support member (not shown). As a result, the sensor heads 18 of 8 channels are arranged at equal angular intervals on the same circumference (C1) about the measurement reference axis A1 at different axial positions of the measurement reference axis A1. Hereinafter, each sensor head 18 at the height position of the first measurement cross section CS1 is referred to as a "first sensor head 18", and each sensor head 18 at the height position of the second measurement cross section CS2 is referred to as a "second sensor head 18". ".

Further, the position and orientation of each sensor head 18 are adjusted so that the direction of the optical axis OA of the emitted measurement light L is parallel to the above-mentioned direction D (see FIG. 3). As a result, the measurement light L emitted from each of the first sensor heads 18 is incident on the measurement points P2 on the outer periphery of the first measurement cross section CS1 facing each of the first sensor heads 18, and each measurement point P2. After being reflected toward the original first sensor head 18, the light is individually received by the original first sensor head 18. On the other hand, the measurement light L emitted from each of the second sensor heads 18 is incident on the measurement point P2 on the outer circumference of the second measurement cross section CS1 facing each second sensor head 18, and at each measurement point P2. After being reflected toward the original second sensor head 18, the light is individually received by the original second sensor head 18.

The displacement meter main body 20 of the fourth embodiment detects the measurement light L for each first sensor head 18, detects the measurement light L for each second sensor head 18, and detects the distance for each of both sensor heads 18. conduct. As a result, the displacement meter main body 20 has the distance from the first sensor head 18 (reference position P1) to the measurement point P2 on the outer periphery of the first measurement cross section CS1 facing each other, and the second sensor head 18 (reference position P1). ) To the measurement point P2 on the outer circumference of the second measurement cross section CS2 facing each other. The displacement meter main body 20 includes a distance detection signal for each first sensor head 18 (hereinafter referred to as a first distance detection signal), a distance detection signal for each second sensor head 18 (hereinafter referred to as a second distance detection signal), and the like. Is output to the computer 14 respectively.

Each distance detection signal input to the computer 14 of the fourth embodiment is input to the analysis unit 29 via the measurement control unit 28 (see FIG. 5). Further, the storage unit 26 of the fourth embodiment stores the position information 32 of each of the first sensor heads 18 and each of the second sensor heads 18.

The analysis unit 29 of the fourth embodiment has the shape of the work W as the shape of the work W based on the first distance detection signal and the second distance detection signal input from the displacement meter main body 20 and the position information 32 acquired from the storage unit 26. The inclination of the central axis A2 of the work W with respect to the measurement reference axis A1 is obtained.

_{FIG. 17 shows the center coordinates V1 (x 01} , y ₀₁ ) of the first measurement cross section CS1 and the center coordinates V2 (x ₀₂ , y ₀₂ ) of the second measurement cross section CS2 used for calculating the inclination of the central axis A2 of the work W. It is explanatory drawing for demonstrating. FIG. 18 is an explanatory diagram for explaining the calculation of the inclination of the central axis A2 of the work W.

As shown in FIG. 17, the analysis unit 29 is centered as the center position of the first measurement cross section CS1 by using the above equations [Equation 2] and [Equation 3] based on the first distance detection signal and the position information 32. The coordinates V1 (x ₀₁ , y ₀₁ ) are obtained. _{Similarly, the analysis unit 29 obtains the center coordinates V2 (x 02} , y ₀₂ ) as the center position of the second measurement cross section CS2 based on the second distance detection signal and the position information 32.

Then, as shown in FIG. 18, the analysis unit 29 is based on the center coordinates V1 (x ₀₁ , y ₀₁ ) and the center coordinates V2 (x ₀₂ , y ₀₂ ) and the known height h (see FIG. 15). , The inclination angle φ of the central axis A2 with respect to the measurement reference axis A1 is obtained by using the following equation [Equation 7].

As described above, the analysis unit 29 of the fourth embodiment can obtain the inclination angle φ of the work W as the shape of the work W based on the first distance detection signal, the second distance detection signal, and the position information 32. As a result, one work W shape measurement is completed. As in the first embodiment, the repetitive control unit 30 repeatedly operates the measurement control unit 28 (displacement meter main body 20) and the analysis unit 29 a plurality of times to obtain the average shape of the work W for a plurality of times. The average value of the inclination angle φ of is obtained.

Since the subsequent processing is basically the same as that of the first embodiment, specific description thereof will be omitted.

As described above, in the shape measuring device 10 of the fourth embodiment, the distance from each first sensor head 18 (reference position P1) to the measurement point P2 on the outer periphery of the first measurement cross section CS1 facing each other and each of them. The distance from the second sensor head 18 (reference position P1) to the measurement point P2 on the outer periphery of the second measurement cross section CS2 facing each other can be collectively detected without contact. As a result, the shape (tilt angle φ) of the work W can be measured without rotating the work W relative to each sensor head 18. As a result, the same effect as that of the first embodiment can be obtained.

In the fourth embodiment, two sets of eight reference positions P1 having different axial positions of the measurement reference axis A1 are set, but three or more sets are set to detect the distance for each reference position. The inclination angle φ may be obtained from the center coordinates of each of the three or more measurement cross sections.

[Modified example of the fourth embodiment]
FIG. 19 is an explanatory diagram for explaining a modified example of the fourth embodiment. In the fourth embodiment, the distances for each sensor head 18 are detected by arranging the sensor heads 18 (first sensor head 18 and second sensor head) at all the reference positions P1.

On the other hand, as shown in FIG. 19, in the modified example of the fourth embodiment, eight channels arranged on the same circumference (C1) in the same arrangement pattern as the reference position P1 with the measurement reference axis A1 as the center. A moving portion 40 for integrally moving the sensor head 18 in the axial direction (Z-axis direction) of the measurement reference axis A1 is provided. The moving unit 40 moves each sensor head 18 to a plurality of axial positions corresponding to the reference position P1 along the Z-axis direction (for example, axial positions corresponding to the first measurement cross section CS1 and the second measurement cross section CS2, respectively). Move in order.

On the other hand, the measurement control unit 28 controls the displacement meter main body 20, and each time the moving unit 40 moves each sensor head 18 to a new axial position, the measurement light L is input to each sensor head 18 and the measurement light L is input to each sensor head 18. The detection of the measurement light L received by each sensor head 18 and the detection of the distance for each sensor head 18 are repeatedly executed. As a result, measurement within the outer peripheral surface of the work W facing each other from each sensor head 18 (for example, on the outer peripheral surface of the first measurement cross section CS1 and the second measurement cross section CS2) is performed for each different axial position of the measurement reference axis A1. The distance to the point P2 can be detected.

Therefore, also in this modification, the inclination angle φ of the work W can be obtained as in the fourth embodiment, so that the same effect as in the fourth embodiment can be obtained. Further, in this modification, the number of sensor heads 18 arranged can be reduced, and the axial position and number of distance detection can be arbitrarily adjusted.

[Shape measuring device of the fifth embodiment]
Next, the shape measuring device 10 according to the fifth embodiment of the present invention will be described. In each of the above embodiments, the radius R (diameter) and roundness of the inner and outer peripheral surfaces of the work W and the inclination angle φ are measured as the shape of the work W, but in the fifth embodiment, the work W is straight. Measure degrees and cylindricity.

FIG. 20 is a side view of the stage 12 and the sensor head 18 constituting the shape measuring device 10 of the fifth embodiment. FIG. 21 is a cross-sectional view taken along line 21A-21A (upper row), a cross-sectional view taken along line 21B-21B (middle row), and a cross-sectional view taken along line 21C-21C (lower row) in FIG. The shape measuring device 10 of the fifth embodiment includes a plurality of sets of 8-channel sensor heads 18, and has basically the same configuration as the shape measuring device 10 of the fourth embodiment. Therefore, those having the same function or configuration as the fourth embodiment are designated by the same reference numerals and the description thereof will be omitted.

As shown in FIGS. 20 and 21, in the fifth embodiment, a plurality of measurement cross sections of the work W perpendicular to the measurement reference axis A1 (first measurement cross section CS1, second measurement cross section CS2, ... Nth measurement cross section CSN). Eight reference positions P1 are preset on the same circumference (C1) around the measurement reference axis A1 at equal angular intervals on the outside of the outer circumference of the above. The measurement reference axes A1 are different from each other in the axial positions of the measurement cross sections CS1 to CSN.

Similar to the fourth embodiment, each sensor head 18 is arranged and supported at each reference position P1 by a support member (not shown). As a result, eight sensor heads 18 are arranged at equal angular intervals on the same circumference (C1) about the measurement reference axis A1 at different axial positions of the measurement reference axis A1. Hereinafter, each sensor head 18 at the height position of the first measurement cross section CS1 is referred to as a “first sensor head 18”, and each sensor head 18 at the height position of the second measurement cross section CS2 is referred to as a “second sensor head 18”. Each sensor head 18 at the height position of the Nth measurement cross section CSN is referred to as "Nth sensor head 18".

The position and orientation of each sensor head 18 are adjusted so that the direction of the optical axis OA of the emitted measurement light L is parallel to the above-described direction D, as in the fourth embodiment. As a result, the measurement light L individually emitted from each sensor head 18 is located in the outer peripheral surface of the work W facing each of the sensor heads 18 (on the outer periphery of the first measurement cross section CS1 to the Nth measurement cross section CSN). It is incident on the measurement point P2, reflected at each measurement point P2 toward the original sensor head 18, and then individually received by the original sensor head 18.

The displacement meter main body 20 of the fifth embodiment detects the measurement light L for each sensor head 18 and detects the distance for each sensor head 18. As a result, the displacement meter main body 20 is placed in the outer peripheral surface of the work W facing each other from each sensor head 18 at different axial positions of the measurement reference axis A1 (first measurement cross section CS1 to Nth measurement cross section CSN). The distance to the measurement point P2 (on the outer circumference) can be detected. The displacement meter main body 20 includes a distance detection signal for each first sensor head 18 (hereinafter referred to as a first distance detection signal), a distance detection signal for each second sensor head 18 (hereinafter referred to as a second distance detection signal), ... A distance detection signal for each N sensor head 18 (hereinafter, referred to as an Nth distance detection signal) is output to the computer 14.

Each distance detection signal input to the computer 14 of the fifth embodiment is input to the analysis unit 29 via the measurement control unit 28 (see FIG. 5). Further, the storage unit 26 of the fifth embodiment stores the position information 32 of the first sensor head 18 to the Nth sensor head 18.

The analysis unit 29 of the fifth embodiment has the shape of the work W as the straightness and the cylinder of the work W based on each distance detection signal input from the displacement meter main body 20 and the position information 32 acquired from the storage unit 26. Find the degree.

First, the analysis unit 29 uses the above equations [Equation 2] and [Equation 3] based on the first distance detection signal, the Nth distance detection signal, and the position information 32 to form the center of the first measurement cross section CS1. The coordinates V1 (x ₀₁ , y ₀₁ ), the center coordinates V2 (x ₀₂ , y ₀₂ ) of the second measurement cross section CS2, ... The center coordinates VN (x _0N , y _0N ) of the Nth measurement cross section CSN are obtained, respectively.

Next, the analysis unit 29 uses the following equation [Equation 8] based on the obtained _{center coordinates V1 (x 01} , y ₀₁ ) to the center coordinates VN (x _0N , y _{0N) for each measurement cross section, and individually The radius R 0i} of each measurement cross section centered on the center coordinates is obtained.

Then, the analysis unit 29 obtains the difference between the maximum value and the minimum value of _{the radius R 0i} of each measurement cross section obtained by the above equation [Equation 8] as the straightness of the work W. Further, the analysis unit 29 obtains the diameter of each measurement cross section (D _{0i , i = 1, 2, ... N) based on the radius R 0i} of each measurement cross section, and sets the maximum and minimum values of the diameter of each measurement cross section. (Dmax-Dmin) is obtained as the cylindricity of the work W. As a result, the straightness and cylindricity of the work W can be measured as the shape of the work W.

This completes one work W shape measurement. As in the first embodiment, the repetitive control unit 30 repeatedly operates the measurement control unit 28 (displacement meter main body 20) and the analysis unit 29 a plurality of times to obtain the average shape of the work W for a plurality of times. The average value of straightness and the average value of cylindricity are obtained.

Since the subsequent processing is basically the same as that of each of the above embodiments, specific description thereof will be omitted.

As described above, in the shape measuring device 10 of the fifth embodiment, from each sensor head 18 to the measurement point P2 in the outer peripheral surface of the work W facing each other for each different axial position of the measurement reference axis A1. Distances can be detected collectively without contact. As a result, the shape (straightness and cylindricity) of the work W can be measured without rotating the work W relative to the sensor head 18. As a result, the same effect as that of the first embodiment can be obtained.

Similar to the modified example of the fourth embodiment shown in FIG. 19 described above, the eight channels arranged on the same circumference (C1) in the same arrangement pattern as the reference position P1 with the measurement reference axis A1 as the center. The sensor head 18 may be sequentially moved to different axial positions of the measurement reference axis A1 by the moving unit 40, and the distance may be detected for each axial position. As a result, the number of sensor heads 18 arranged can be reduced, and the axial position and number of distance detection can be arbitrarily adjusted.

[others]
The configurations of the above embodiments may be combined as appropriate. Further, in the fourth and fifth embodiments, the distance to each measurement point P2 on the inner peripheral surface of the work W is detected, and up to each measurement point P2 on both the outer peripheral surface and the inner peripheral surface of the work W. Various shapes of the work W may be measured by detecting the distance of the work W.

In each of the above embodiments, the measurement light L individually received by each sensor head 18 is detected (photoelectric conversion) by the displacement meter main body 20, but the measurement light L may be detected by each sensor head 18. Further, instead of detecting the distance for each sensor head 18 based on the detection result of the measurement light L for each sensor head 18 in the displacement meter main body 20, the computer 14 performs the distance detection, or instead of each sensor head 18. A known distance measuring meter (displacement meter) may be provided respectively.

The non-contact displacement meter 13 of each of the above embodiments detects the distance for each sensor head 18 using the measurement light L, but is of various non-contact type using various signals (sounds or the like) other than the measurement light L. The distance may be detected by the distance detection unit. Further, instead of the non-contact type distance detection unit, for example, a contact type distance detection unit that detects the distance with a probe provided in a known contact type coordinate measuring machine, roundness measuring machine, or the like is used. You may.

In each of the above embodiments, the sensor heads 18 (reference positions P1) are arranged at equal intervals on the same circumference centering on the measurement reference axis A1, but if they are on the same circumference, the sensor heads 18 are arranged. The position is not particularly limited. In order to measure the shape of the work W with high accuracy regardless of the position, posture, and type (shape) of the work of the work W, the position (distance and angle position) of the measurement point on the peripheral surface (measured surface) ) Are preferably obtained at equal intervals. Therefore, as shown in each of the above embodiments, it is preferable that the sensor heads 18 are arranged at equal angular intervals on the same circumference with the measurement reference axis A1 as the center.

In each of the above embodiments, the case of measuring the shape of the cylindrical work W has been described as an example, but the cylindrical work W and the work including the peripheral surface (outer peripheral surface or inner peripheral surface, etc.) are partially included. The present invention can also be applied when measuring the shape of W. The present invention can also be applied to the case of measuring the shape of a work W having various shapes having various shapes of surfaces to be measured.

In each of the above embodiments, the radius R (diameter), roundness, inclination angle φ, straightness, and cylindricity have been described as examples of the shape of the work W, but other shapes (including dimensions) have been described. The present invention can also be applied to the case of measurement.

10 ... Shape measuring device, 12a ... Reference plane, 13 ... Non-contact displacement meter, 14 ... Computer, 18 ... Sensor head, 20 ... Displacement meter body, 25 ... Control unit, 29 ... Analysis unit, 30 ... Repeat control unit, 32 … Position information, 35… Reflector

Claims (13)

The reference plane on which the work is placed and
From the reference position to the measurement point in the measured surface of the work facing the reference position for each reference position set on the same circumference centered on the measurement reference axis perpendicular to the reference plane. A distance detector that detects the distance and
An analysis unit that obtains the shape of the work based on known position information of each reference position with respect to the measurement reference axis and the distance for each reference position detected by the distance detection unit.
Equipped with a,
A shape measuring device in which the analysis unit obtains the shape of the work based on the result of detecting the distance by the distance detection unit without rotating the work relative to the distance detection unit. The shape measuring device according to claim 1, wherein the reference position is set at equal angular intervals on the same circumference with the measurement reference axis as the center. A repeat control unit for repeatedly operating the distance detection unit and the analysis unit a plurality of times is provided.
The shape measuring device according to claim 1 or 2, wherein the analysis unit obtains an average shape obtained by averaging the shapes of the work obtained a plurality of times. Each reference position is provided with a measurement unit that incidents a signal from the reference position to the measurement point facing the reference position and individually detects the signal reflected at each measurement point.
The shape measuring device according to any one of claims 1 to 3, wherein the distance detecting unit detects the distance for each reference position based on the detection result of the signal for each measuring point by the measuring unit. The signal is measurement light and
The fourth aspect of claim 4 is that the direction of the optical axis of the measurement light incident on the measurement point from the reference position is a direction perpendicular to the measurement reference axis in the plane including the reference position and the measurement reference axis. Shape measuring device. When the work is cylindrical or cylindrical and the surface to be measured is the outer peripheral surface of the work, the reference position is set to the outside of the outer peripheral surface according to any one of claims 1 to 5. The shape measuring device described. The method according to any one of claims 1 to 5, wherein when the work is cylindrical and the surface to be measured is the inner peripheral surface of the work, the reference position is set inside the inner peripheral surface. Shape measuring device. When the work is cylindrical and the surface to be measured is the inner peripheral surface of the work.
The reference position is set to 3 or more on the same circumference inside the inner peripheral surface.
The measuring unit
A plurality of reflectors individually provided for each reference position, and
A plurality of optical units arranged at intervals in the direction perpendicular to the reference plane, and a plurality of optical units individually arranged on the same circumference and at positions facing the individual reflectors. And with
For each of the optical units, the measurement light is emitted to the reflector facing the optical unit, and the measurement light incident from the reflector facing the optical unit is detected.
For each reflector, the measurement light incident from the optical unit facing the reflector is reflected and incident on the measurement point facing the reflector, and the measurement light reflected at the measurement point is reflected. Reflects toward the optical unit facing the reflector,
The distance detection unit detects the distance for each reference position based on the size of the known distance between the reference position and the optical unit and the detection result of the measurement light for each optical unit. Item 5. The shape measuring device according to Item 5. When the work has a peripheral surface and the surface to be measured is the peripheral surface,
The analysis unit obtains the radius of the peripheral surface and the roundness of the peripheral surface as the shape of the work based on the position information and the distance for each reference position. Any one of claims 1 to 8. The shape measuring device according to. The reference position is set to 3 or more on the same circumference having a plurality of different axial positions of the measurement reference axis.
The shape measuring device according to any one of claims 1 to 7, wherein the distance detecting unit detects the distance for each reference position. When the work is cylindrical or cylindrical and the surface to be measured is at least one of the outer peripheral surface and the inner peripheral surface of the work.
The analysis unit obtains the center position of the peripheral surface for each axial position based on the position information and the distance for each reference position detected by the distance detection unit, and the analysis unit obtains the center position of the peripheral surface for each axial position. The shape measuring device according to claim 10, wherein the shape of the work is an inclination angle of the work with respect to the measurement reference axis based on the center position. When the work is cylindrical or cylindrical and the surface to be measured is at least one of the outer peripheral surface and the inner peripheral surface of the work.
The analysis unit obtains the radius of the peripheral surface for each axial position based on the position information and the distance for each reference position detected by the distance detection unit, and the radius for each axial position. The shape measuring device according to claim 10, wherein straightness and cylindricity are obtained as the shape of the work based on the above. In the shape measurement method for measuring the shape of a work placed on a reference plane,
From the reference position to the measurement point in the measured surface of the work facing the reference position for each reference position set on the same circumference centered on the measurement reference axis perpendicular to the reference plane. Distance detection step to detect distance and
An analysis step for obtaining the shape of the work based on known position information of each reference position with respect to the measurement reference axis and the distance for each reference position detected in the distance detection step.
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A shape measuring method for obtaining the shape of the work in the analysis step based on the result of detecting the distance in the distance detection step without rotating the work relative to the reference position.

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