WO2022185740A1 - Workpiece shape measurement device, workpiece shape measurement system, workpiece shape measurement method, and workpiece shape measurement program - Google Patents

Abstract

A displacement acquisition unit (35) of a workpiece shape measurement device (1) successively acquires displacement measurement results for the surface (91) of a workpiece (90) from a displacement sensor (2) moving in a movement direction. A correction section extraction unit (38) extracts a section where the displacement measurement results continuously increase or decrease according to positional variation in the movement direction as a correction section (α) including a boundary (95) between a recess (92) or protrusion (93) and the surface (91). A correction unit (39) derives the position of the boundary (95) inside the correction section (α) extracted by the correction section extraction unit (38) and corrects the measurement results such that the displacement changes sharply at the boundary (95).

Description

Work shape measuring device, work shape measuring system, work shape measuring method and work shape measuring program

The present invention relates to a workpiece shape measuring device that measures the displacement of the surface of a workpiece and measures the shape of the workpiece, a workpiece shape measuring system, a workpiece shape measuring method, and a workpiece shape measuring program.

A displacement sensor that measures the displacement of the surface of the work is sometimes used to measure the shape of the work.
For example, Patent Document 1 uses a two-dimensional laser displacement gauge. A two-dimensional laser displacement meter irradiates a laser on a line perpendicular to the running direction of a belt conveyor that conveys a work, and obtains slice data of the work on the line.

JP 2018-202512 A

Some workpieces have irregularities such as holes, grooves, protrusions or ribs on their surfaces. At the boundary between the unevenness and the surface, there is a displacement according to the depth of the concave portion and the height of the convex portion.
Then, for example, when this boundary passes through the laser irradiation range (laser spot diameter), the irradiation range includes both the surface and the unevenness. There is a risk that the measurement result of the displacement sensor will be an ambiguous numerical value that is neither a value indicating the height of the surface nor a value indicating the height of the unevenness. Therefore, it has been difficult to accurately extract the position of the boundary and to measure the position and shape of the unevenness with high accuracy.

Therefore, an object of the present invention is to accurately measure the shape of unevenness when measuring the displacement of the surface of a workpiece provided with unevenness.

A workpiece shape measuring device according to one aspect of the present invention includes a displacement sensor control section, a movement control section, a displacement acquisition section, a correction section extraction section, and a correction section, and cooperates with the displacement sensor and the movement mechanism. The displacement sensor is arranged so as to face the surface of the work on which the recesses or protrusions are provided. The movement mechanism relatively moves the displacement sensor with respect to the workpiece in a movement direction orthogonal to the facing direction. The displacement sensor control unit controls the displacement sensor, causes the displacement sensor to irradiate the surface of the workpiece with point-like light, and measures the displacement of the surface of the workpiece in the opposing direction. The movement control unit drives the movement mechanism. The displacement acquisition unit sequentially acquires displacement measurement results from the displacement sensor that is moving in the movement direction. The correction section extracting unit extracts a section in which the measurement result continuously increases or decreases according to the positional change in the movement direction as a correction section including the boundary between the concave portion or the convex portion and the surface. The correction unit derives the position of the boundary inside the correction section extracted by the correction section extraction unit, and corrects the measurement result so that the displacement changes sharply at the boundary.

Here, in the interval where the measurement result of the displacement sensor continuously increases or decreases, that is, in the interval where the measurement result continues to show ambiguous numerical values, the boundary between the concave or convex portion and the surface covers the irradiation range of the point-like light. It is highly probable that it passed. In the above configuration, the section is extracted as a correction section. Then, the position of the boundary is derived inside the correction section, and the measurement result is corrected so that the displacement changes more steeply at the derived position.

As a result, the change in displacement near the boundary becomes clearer, and the shape of the concave portion or convex portion can be measured with high accuracy.
It should be noted that when the increase and decrease of the measurement result alternate in a short period, it is simply considered that the displacement of the non-flat surface is being measured with high accuracy microscopically. It is possible to determine whether or not there is a boundary by determining whether or not it is a section that continuously increases or decreases.

Here, when the peripheral surface of the concave portion or convex portion is perpendicular to the surface of the workpiece, the boundary passes through the light irradiation range while the displacement sensor moves by a distance corresponding to the spot diameter. If the peripheral surface of the concave or convex portion forms a tapered surface that is inclined with respect to the direction perpendicular to the surface of the workpiece, the displacement sensor detects the distance corresponding to the spot diameter plus the distance corresponding to the inclination. The boundary passes within the illumination range of the light while moving by If the continuous change in displacement ends before the displacement sensor moves a distance corresponding to the spot diameter, then a characteristic shape such as the boundary of a concave or convex portion is included in the movement interval. Not likely.

Therefore, when the measurement result continuously increases or decreases by a predetermined distance or more in the moving direction, the corrected section extracting section may extract the continuously changing section as the corrected section. In this case, the predetermined distance may be determined in advance based on the spot diameter of the light with which the workpiece is irradiated.
As a result, the corrected section becomes a section in which the measurement result continuously increases or decreases by a predetermined distance or more, and there is a high probability that such a corrected section includes a boundary. A characteristic shape such as a boundary of a concave portion or a convex portion can be accurately measured without being overlooked.

The correction unit may derive the center of the correction section as the position of the boundary.
This facilitates the derivation of the boundary position.
Here, if the peripheral surface of the concave portion or convex portion is inclined with respect to the direction perpendicular to the surface of the workpiece, the movement distance of the displacement sensor required for the boundary to finish passing through the light irradiation range is long. Become.

Therefore, the correction unit may derive the dimension of the boundary in the movement direction according to the dimension of the correction section in the movement direction.
This makes it possible to accurately measure the shape of the concave portion or the convex portion while taking into account the slope of the boundary.
The correction unit adjusts the displacement at the boundary from a first end displacement value, which is the measurement result at the first end of the correction section, to a second end displacement value, which is the measurement result at the second end of the correction section. You may correct the measurement result.

In the above configuration, the first end displacement value and the second end displacement value correspond to the maximum and minimum values of the measurement results that continuously increase or decrease within the correction section. By connecting these two displacement values at the position of the boundary derived inside the correction interval, the measurement result is corrected to change sharply.
This correction makes it possible to make the measurement result closer to the actual shape near the boundary, and to accurately measure the shape of the concave portion or the convex portion.

The correction unit may correct the measurement result so that the displacement changes at the first end displacement value in a first section from the first end to the boundary in the correction section. The correction unit may correct the measurement result so that the displacement changes at the second end displacement value in a second section from the boundary to the second end of the correction section.
Before correction, the measurement result changes from the first end displacement value to the second end displacement value over the entire correction interval. On the other hand, after correction, the measurement result is corrected to the first end displacement value from the first end of the correction section to the boundary, and at the boundary, the first end displacement value changes to the second end displacement value more steeply. It is corrected to change and is corrected to the second end displacement value from the boundary to the second end of the correction section.

This correction makes it possible to bring the measurement result within the correction section closer to the actual shape of the boundary and its surrounding area, and to accurately measure the shape of the workpiece.
The workpiece shape measuring apparatus may further include a center position measuring unit that measures the center position of the concave portion or the convex portion when viewed in the opposing direction based on the position of the boundary derived by the correcting unit.
According to the above configuration, since the shape in the vicinity of the boundary is accurately measured, it is possible to accurately measure the center position of the concave portion or the convex portion based on the measurement result.

The workpiece shape measuring device may further include a shape measuring unit that measures the shape of the concave portion or convex portion when the workpiece is viewed in the opposing direction based on the position of the boundary derived by the correcting unit.
According to the above configuration, since the shape in the vicinity of the boundary is measured with high accuracy, the overall shape of the concave portion or convex portion can also be measured with high accuracy based on the measurement result.
A workpiece shape system according to one aspect of the present invention includes the workpiece shape measuring device, the displacement sensor, and the moving mechanism. The displacement sensor is arranged to face the surface of the work on which the concave portion or the convex portion is provided, irradiates the surface of the work with point-like light, and measures the displacement of the surface of the work in the facing direction. The movement mechanism relatively moves the displacement sensor with respect to the workpiece in a movement direction orthogonal to the facing direction.

The system has technical features corresponding to the technical features of the workpiece shape measuring device. Therefore, it is possible to clarify the change in displacement near the boundary and accurately measure the shape of the concave portion or the convex portion.
The displacement sensor may output, as a single measurement result, an average value of displacements at a plurality of locations within an irradiation range of light irradiated onto the surface of the workpiece.

With this displacement sensor, when the boundary passes through the range of light irradiation, the measurement result shows an ambiguous numerical value that neither indicates the displacement of the surface nor the value that indicates the displacement of the bottom surface of the concave portion or the top surface of the convex portion. There is a risk. Even in such a case, the workpiece shape measurement derives the position of the boundary and corrects the measurement result, so that the workpiece shape can be measured with high accuracy.
Here, the measurement principle of a two-dimensional laser displacement meter generally follows triangulation, and by detecting the reflected light returning in a direction that is inclined to the light emission direction, the displacement of the part irradiated with light is measured. do. Therefore, when light is irradiated into the concave portion, there is a possibility that the reflected light in the inclined direction is blocked by the inner peripheral surface of the concave portion and cannot return to the two-dimensional laser displacement gauge.

Therefore, the displacement sensor may emit light in the opposite direction, detect reflected light returning from the surface of the workpiece in the same direction as the light emission direction, and measure the displacement of the portion irradiated with the light.
This displacement sensor is of the so-called "coaxial type". Therefore, the displacement sensor can detect the reflected light even if the surface of the work has a concave portion. Since such a displacement sensor moves relative to the work, the shape of the recess can be measured with high accuracy.

The displacement sensor may have confocal optics.
This displacement sensor is of the so-called "coaxial confocal type". Therefore, the displacement of the surface and the shape of the workpiece can be measured with higher accuracy than, for example, a sensor that uses triangulation as a measurement principle.
a first moving mechanism for moving the displacement sensor in a first moving direction orthogonal to the opposing direction; a second moving mechanism for moving the workpiece in a second moving direction orthogonal to the opposing direction and the first moving direction; may have

Thereby, the position of the displacement sensor relative to the workpiece can be independently controlled in the first movement direction and the second movement direction. Displacement can be measured for each position in the first movement direction, and displacement can be measured for each position in the second movement direction.
A workpiece shape measuring method according to one aspect of the present invention includes a displacement sensor control process, a movement control process, a displacement acquisition process, a correction section extraction process, and a correction process. In the displacement sensor control step, the displacement sensor arranged opposite to the surface of the workpiece provided with the concave portion or the convex portion is controlled, and the displacement sensor is caused to irradiate the surface of the workpiece with point-like light, thereby detecting the displacement of the workpiece in the opposing direction. Measure the displacement of the surface. In the movement control step, a movement mechanism is driven that relatively moves the displacement sensor with respect to the workpiece in a movement direction orthogonal to the facing direction. In the displacement acquisition step, displacement measurement results are sequentially acquired from the displacement sensor that is moving in the movement direction. In the correction section extraction step, a section in which the measurement result continuously increases or decreases according to the change in position in the moving direction is extracted as a correction section including the boundary between the recess or protrusion and the surface. In the correction step, the position of the boundary is derived inside the correction section, and the measurement result is corrected so that the displacement abruptly changes at the boundary.

A work shape measurement program according to one aspect of the present invention causes a computer to execute the above work shape measurement method.
The method and program have technical features corresponding to those of the workpiece shape measuring apparatus. Therefore, the displacement near the boundary can be clarified, and the shape of the concave portion or convex portion can be accurately measured.

(Effect of the invention)
ADVANTAGE OF THE INVENTION According to this invention, when measuring the displacement of the surface of the workpiece|work in which unevenness|corrugation was provided, the shape of unevenness|corrugation can be measured accurately.

BRIEF DESCRIPTION OF THE DRAWINGS It is a block diagram which shows the workpiece|work shape measuring device which concerns on embodiment of this invention, and a workpiece|work shape measuring system provided with the same. 1 is a perspective view showing a workpiece shape measuring system; FIG. (A) is a plan view showing an example of a work, and (B) is a BB arrow view of (A). (C) is a diagram showing a boundary according to a modification. It is a schematic diagram which shows the structure of a displacement sensor. It is a front view which shows operation|movement of a displacement sensor. (A) is a diagram showing the measurement result of the displacement sensor when the boundary is not inclined with respect to the direction perpendicular to the surface (light emission direction). (B) is a BB arrow view of (A). (A) is a diagram showing measurement results of a displacement sensor when a boundary is inclined. (B) is a BB arrow view of (A). (A) and (B) are diagrams showing correction processing of the measurement result within the correction section when the boundary is not inclined. (A) and (B) are diagrams showing correction processing of the measurement result within the correction section when the boundary is inclined. 4 is a flow chart showing a workpiece shape measuring method according to an embodiment of the present invention; It is a figure which shows the movement path|route of a displacement sensor. It is a figure which shows the measurement processing of a center position. It is a figure which shows the measurement processing of a shape. It is a figure which (A) and (B) show a square recessed part, (C) shows a rectangular recessed part, and (D) shows a regular polygonal recessed part. (A) is a diagram showing a process of measuring the shape of a square concave portion by applying the movement path according to the embodiment. (B) is a diagram showing a process of measuring the shape of a square concave portion by applying a movement path according to a modification. It is a figure which shows the derivation|leading-out process of the position of a boundary which concerns on a modification.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. The same reference numerals are given to the same or corresponding elements throughout the drawings, and redundant detailed description is omitted.
(Work shape measurement system)
1 and 2 show a workpiece shape measuring system 100 according to a first embodiment of the invention. A work shape measuring system 100 includes a work shape measuring device 1 , a displacement sensor 2 , a work supporting device 3 , a sensor supporting frame 4 , a moving mechanism 5 and a position sensor 8 . The moving mechanism 5 has a first moving mechanism 6 and a second moving mechanism 7 . Position sensor 8 has a first position sensor 9 and a second position sensor 10 .

The workpiece shape measuring device 1 is a computer having a CPU, a memory and an input/output interface. The workpiece shape measuring device 1 is implemented by, for example, one or more PLCs (Programmable Logic Controllers), a server device, or a combination thereof. In addition, the workpiece shape measuring device 1 may include a computer built in the housing 21 (see FIG. 4) of the displacement sensor 2 .

The workpiece shape measuring device 1 is communicably connected to the displacement sensor 2, the first moving mechanism 6, the second moving mechanism 7, the first position sensor 9 and the second position sensor .
Furthermore, the workpiece shape measuring device 1 is communicably connected to a terminal device 80 operated by a worker at the production site where the workpiece shape measuring system 100 is introduced. The terminal device 80 is, for example, a personal computer, and also has an input device such as a keyboard for inputting operating conditions of the workpiece shape measuring system 100 and a display for displaying measurement results and the like.

The memory of the work shape measuring device 1 stores a work shape measuring program that causes the work shape measuring device 1, which is an example of a computer, to execute the work shape measuring method (see FIG. 10) according to this embodiment. The CPU reads out the work shape measurement program stored in the memory and executes information processing according to the procedure instructed by the work shape measurement program. Thereby, the workpiece shape measuring method is executed.

The workpiece shape measurement system 100 uses the displacement sensor 2 to measure the displacement of the surface 91 of the workpiece 90, thereby measuring the shape of the workpiece 90. The workpiece shape measuring system 100 is preferably used for measuring the shape of a workpiece 90 having a concave portion 92 or a convex portion 93 provided on its surface 91, particularly a workpiece 90 having fine concave portions 92 and convex portions 93. FIG. The type, overall shape and material of the workpiece 90 are not particularly limited.

As shown in FIGS. 3(A) and 3(B), in the present embodiment, the workpiece 90 has a thin plate shape as a whole. The workpiece 90 is, for example, a cutting plate used in singulation, which is one of the post-processes of semiconductor manufacturing. The workpiece 90 has a rectangular frame member 90a and a suction member 90b fitted inside thereof. The upper surface of the adsorption member 90b forms the surface 91 of the workpiece 90. As shown in FIG.

The frame member 90a is provided with a pair of flanges protruding from both side edges, and mounting holes 92a are formed in each flange. A large number of adsorption holes 92b arranged in a matrix are formed in the adsorption member 90b. The attachment hole 92 a and the suction hole 92 b are examples of the recess 92 recessed downward from the surface 91 . A portion of the frame member 90 a surrounding the adsorption member 90 b is an example of a convex portion 93 projecting upward from the surface 91 .

The concave portion 92 is, for example, a non-penetrating circular hole. The attachment hole 92a has a larger diameter than the suction hole 92b. The reference sign “φ92” is the diameter of the recess 92, and the reference sign “D92” is the depth of the recess 92 (the height from the surface 91 to the bottom of the recess 92).
A boundary 95 is formed in the workpiece 90 between the recess 92 and the surface 91 . The boundary 95 is the edge of the opening on the surface 91 of the recess 92 or the step surface between the surface 91 and the bottom surface of the recess 92 . A similar boundary 95 is also formed between the convex portion 93 and the surface 91 of the workpiece 90 .

In the example shown in FIG. 3B, the boundary 95 is not inclined with respect to the direction perpendicular to the surface 91 (thickness direction). In the example shown in FIG. 3C, the mounting hole 92a is inclined with respect to the plate thickness direction. Reference sign “W95” is the dimension (width) of boundary 95 . In the example shown in FIG. 3B, the dimensions of boundary 95 are zero values. In the example shown in FIG. 3C, the boundary 95 has a dimension W95 corresponding to the slope. The mounting hole 92a is a circular hole. In this case, the dimension W95 is the difference between the radius of the mounting hole 92a on the surface 91 side and the radius of the bottom side of the mounting hole 92a.
At the site where such workpieces 90 are produced, workers perform inspection work to check whether the positions and shapes of the concave portions 92 (especially the finer suction holes 92b) are within tolerance before shipment. The work shape measurement system 100 can help save labor in this inspection work and help improve the quality of the work 90 to be shipped.

(displacement sensor)
FIG. 4 shows the displacement sensor 2 . The displacement sensor 2 emits white light containing light of multiple wavelengths, and the confocal optical system 12 adjusts the emitted light L and its reflected light. The reflected light detected by the displacement sensor 2 is coaxial with the emitted light. That is, the displacement sensor 2 according to this embodiment is a so-called "white coaxial confocal type".

The displacement sensor 2 has a head 11 and a housing 21. The head 11 incorporates a confocal optical system 12 and emits light L. The housing 21 incorporates a light source 22 , a spectroscope 23 , a light receiving section 24 and a control circuit 25 . The head 11 is physically separated from the housing 21 and mechanically connected to the housing 21 via the flexible optical fiber 20 . Optical fiber 20 optically connects confocal optics 12 with light source 22 and spectroscope 23 .

The head 11 is formed in a cylindrical shape and has an object surface and an opposite surface at both ends in the axial direction. The object plane faces the surface 91 of the workpiece 90 . A head-side open end of the optical fiber 20a is provided on the opposite surface. The housing-side end of the optical fiber 20 a is connected to one end of the optical fiber 20 d inside the housing 21 . The other end of the optical fiber 20d is bifurcated and connected to the light source 22 via the optical fiber 20b and to the spectroscope 23 via the optical fiber 20c.

The light source 22 emits light of multiple wavelengths (for example, white light). A white light emitting diode (LED) is a preferred example of light source 22 . Light emitted from the light source 22 is guided into the head 11 via optical fibers 20b, 20d, and 20a, adjusted by the confocal optical system 12, and emitted from the object plane of the head 11 toward the work 90. FIG. The optical axis is positioned on the central axis of head 11 .

The confocal optical system 12 has a diffraction lens 13, an objective lens 14 and a condenser lens 15. The diffraction lens 13 causes the light emitted from the light source 22 to have chromatic aberration along the optical axis direction. The objective lens 14 is arranged on the object plane side with respect to the diffraction lens 13 , and converges the light with chromatic aberration by the diffraction lens 13 onto the surface 91 of the workpiece 90 . The condenser lens 15 is arranged on the side opposite to the diffraction lens 13 and is adjusted so that the numerical aperture (NA) of the optical fiber 20 and the numerical aperture of the diffraction lens 13 match.

The light condensed by the objective lens 14 is irradiated on the surface 91 of the workpiece 90 in a point-like manner and reflected on the surface 91 . Reflected light returns in the same direction as the exit direction. The confocal optical system 12 focuses the light focused on the surface 91 of the workpiece 90 at the head-side open end of the optical fiber 20a. Of the light condensed by the objective lens 14 , the head-side open end allows light that is focused on the surface 91 of the work 90 to pass through, and blocks light of wavelengths that are not focused on the surface 91 of the work 90 . That is, the head-side open end functions as a pinhole. Light passing through the head-side open end is guided to a spectroscope 23 via optical fibers 20a, 20d, and 20c.

The spectroscope 23 has a diffraction grating 23b that divides the light returning from the head 11 by wavelength. The concave mirror 23a reflects the light returning from the head 11 to enter the diffraction grating 23b. The condenser lens 23 c collects the light emitted from the diffraction grating 23 b on the light receiving section 24 .
The light receiving unit 24 measures the intensity of light emitted from the spectroscope 23 for each wavelength. The light receiving unit 24 is composed of, for example, a photoelectric conversion element. An image sensor using a charge coupled device (CCD) or a complementary metal oxide semiconductor (CMOS) is a suitable example of the light receiving section 24 .
The control circuit 25 controls operations of the light source 22 and the light receiving section 24 . The control circuit 25 also controls the measurement unit 26 (FIG. 1 ).

(displacement measurement)
As shown in FIG. 5, the displacement sensor 2 is arranged so that the object plane faces the surface 91 of the workpiece 90 in the optical axis direction while being spaced from the surface 91 in the optical axis direction.

Hereinafter, this facing direction will be referred to as "opposing direction Z". A direction in a plane perpendicular to the opposing direction Z is called a "moving direction". In a plane orthogonal to the facing direction Z, a certain linear direction is defined as a "first moving direction X", and a direction perpendicular to the first moving direction X is defined as a "second moving direction Y". The facing direction Z corresponds to the optical axis direction (emission direction) of the light L, and corresponds to the direction perpendicular to the surface 91 of the workpiece 90 (board thickness direction). In this embodiment, as a preferred example, the facing direction Z is vertical, and the moving directions X and Y are horizontal. Therefore, the facing direction Z may be represented by up and down, and the movement directions X and Y may be represented by front, rear, left, and right.

The displacement sensor 2 emits light L in the opposing direction Z from the object plane. The light L is irradiated on the surface 91 of the workpiece 90 in a dot shape. Hereinafter, the point-like light on the surface 91 will be referred to as "spot light s". The spot light s has a circular shape with a diameter of the spot diameter φs. Due to the action of the confocal optical system 12, the light L is tapered and conical.
The light receiving unit 24 detects reflected light, and the measuring unit 26 measures the displacement of the surface 91 with respect to a certain reference position in the facing direction Z. The "reference position" may be set anywhere. In this embodiment, as a mere example, the reference position is set on the object plane. The displacement sensor 2 outputs the distance in the facing direction Z from the object plane as the displacement measurement result.

With reference to the displacement sensor 2 at the right position, when the spot light s is irradiated onto the surface 91, the measurement result of the displacement becomes a value indicating the distance Z91 from the object plane to the surface 91. Referring to the displacement sensor 2 at the left position, when the spot light s is irradiated on the bottom surface of the concave portion 92, the measurement result of the displacement becomes a value indicating the distance Z92 from the object plane to the bottom surface. The depth D92 of the recess 92 can be detected based on the two measurement results.

If the principle of displacement measurement follows triangulation like a general laser displacement meter, the sensor detects the reflected light (see the dashed line) returning in a direction that is tilted with respect to the emission direction. Therefore, the reflected light may be blocked by the inner peripheral surface of the concave portion 92 and the displacement may not be measured. In contrast, in the present embodiment, the displacement sensor 2 is coaxial, and detects reflected light returning from the bottom surface of the recess 92 in the same direction as the emission direction. Therefore, the reflected light is not blocked by the workpiece 90, and the displacement can be stably measured. Therefore, the uneven shape of the workpiece 90 can be measured more precisely.

By fixing the position of the displacement sensor 2 in the facing direction Z, fixing the posture of the head 11, and moving the head 11 in the moving direction, data indicating a two-dimensional shape defined by the moving direction and the facing direction Z. (so-called "slice data") are obtained.
Displacement can be measured for each position of the displacement sensor 2 in the first movement direction X with respect to the workpiece 90 without using a two-dimensional laser displacement gauge.
The head 11 incorporates the confocal optical system 12 but does not include the light source 22 and the light receiving section 24 . Since the head 11 is made compact and lightweight, the head 11 can be moved at high speed with small energy. The optical fiber 20 connecting the head 11 to the housing 21 has flexibility. Therefore, the movement of the head 11 is not hindered.

(support mechanism)
Returning to FIG. 2, the work support device 3 and the sensor support frame 4 are placed on the floor of the work 90 production site. The work supporting device 3 supports the work 90 . A sensor support frame 4 supports the displacement sensor 2 .

The sensor support frame 4 is formed in a gate shape or a bridge shape, for example. The sensor support frame 4 has a pair of pillars and a beam connecting the upper ends of the pillars. The beam extends in the first direction X of movement. The work supporting device 3 is arranged between the pair of pillars in the first moving direction X and below the beam in the opposing direction Z. As shown in FIG.
The moving mechanism 5 relatively moves the displacement sensor 2 in the moving directions X and Y with respect to the workpiece 90 . The first moving mechanism 6 is provided on the sensor support frame 4 . The first moving mechanism 6 moves the displacement sensor 2 in the first movement direction X with respect to the floor surface. The second moving mechanism 7 is provided in the work supporting device 3 . The second moving mechanism 7 moves the workpiece 90 in the second movement direction Y with respect to the floor surface.

As shown in FIGS. 1 and 2, the first moving mechanism 6 has a guide member 6a, a holding member 6b, a first moving actuator 6c, a first power transmission mechanism 6d and a first encoder 6e. The guide member 6a is attached to the front face of the beam and extends in the first movement direction X. As shown in FIG. The holding member 6b is supported by the guide member 6a so as to be able to reciprocate in the first moving direction X. As shown in FIG. The holding member 6b holds the head 11 of the displacement sensor 2 so that the position of the head 11 with respect to the floor surface in the facing direction Z is fixed, and the attitude of the head 11 around the axis perpendicular to the optical axis is fixed. hold. The head 11 is supported by the sensor support frame 4 via the holding member 6b and the guide member 6a, and emits light L in the opposing direction Z. As shown in FIG.

The first moving actuator 6c generates power for moving the holding member 6b and the head 11 held thereon. The first power transmission mechanism 6d transmits the power generated by the first movement actuator 6c to the holding member 6b. The first movement actuator 6c is, for example, a servomotor, and generates rotational power. The first power transmission mechanism 6d converts rotation into linear motion in the first movement direction X, such as a ball screw mechanism, a rack and pinion mechanism, or a belt and pulley mechanism. The first encoder 6e detects the movement amount or position of the first moving actuator 6c.

The second moving mechanism 7 has a movable support 7a, a second moving actuator 7b, a second power transmission mechanism 7c and a second encoder 7d. The movable support 7a is formed in a flat plate shape and is supported on the frame 3a of the work supporting device 3 so as to be movable in the second moving direction Y. As shown in FIG. A workpiece 90 is placed on the upper surface of the movable support 7a, and a surface 91 of the workpiece 90 faces the head 11 above.

The second movement actuator 7b generates power for moving the movable support 7a and the workpiece 90 supported by it. The second power transmission mechanism 7c transmits the power generated by the second movement actuator 7b to the movable support 7a. The second movement actuator 7b is, for example, a servomotor, and generates rotational power. The second power transmission mechanism 7c converts rotation into linear motion in the second movement direction Y, such as a ball screw mechanism. The second encoder 7d detects the movement amount or position of the second moving actuator 7b.

The head 11 can move relative to the work 90 in the first movement direction X and the second movement direction Y so as to be able to face the entire surface 91 of the work 90 . Further, the position of the displacement sensor 2 with respect to the workpiece 90 is independently controlled in the first moving direction X and the second moving direction Y. A displacement is measured for each position in the first moving direction X, and a displacement is measured for each position in the second moving direction Y.
Since the position of the displacement sensor 2 in the facing direction Z is fixed, the displacement measurement result is stable. Since the work 90 is supported by the movable support 7a and the position in the opposing direction Z is fixed, the displacement measurement result is stable.

(Position detection)
The first position sensor 9 detects the position of the head 11 of the displacement sensor 2 with respect to the workpiece 90 in the first moving direction X. As shown in FIG. In this embodiment, the first position sensor 9 is composed of a first linear scale 9A. The first linear scale 9A is installed adjacent to the sensor movable range by the first moving mechanism 6 . Specifically, it is attached to the beam of the sensor support frame 4 and provided parallel to the guide member 6a. The first linear scale 9A monitors the position of the displacement sensor 2 in the first movement direction X within the sensor movable range.

The second position sensor 10 detects the position of the head 11 of the displacement sensor 2 with respect to the workpiece 90 in the second moving direction Y. In this embodiment, the second position sensor 10 is composed of a second linear scale 10A. The second linear scale 10A is installed adjacent to the work movable range by the second moving mechanism 7 . Specifically, it is provided on the floor surface or the frame 3a. The second linear scale 10A monitors the position of the work 90 in the second movement direction Y within the work movable range.

The first encoder 6e can function as the first position sensor 9. The second encoder 7d can function as the second position sensor 10. FIG. However, these detection results include the backlash of the first power transmission mechanism 6d or the second power transmission mechanism 7c. In this embodiment, since the positions of the displacement sensor 2 and the workpiece 90 are directly monitored, the relative position of the displacement sensor 2 with respect to the workpiece 90 can be detected with high accuracy.

(Work shape measuring device)
As shown in FIG. 1, the workpiece shape measuring apparatus 1 executes a workpiece shape measuring program to provide a storage unit 30, an input unit 31, an output unit 32, a displacement sensor control unit 33, a movement control unit 34, and a displacement acquisition unit. 35 , a position acquisition unit 36 , a position synchronization unit 37 , a correction section extraction unit 38 , a correction unit 39 , a center position measurement unit 41 , a shape measurement unit 42 and a determination unit 43 . The movement control section 34 has a first movement control section 34a and a second movement control section 34b. The position acquisition section 36 has a first position acquisition section 36a and a second position acquisition section 36b.

The storage unit 30 stores information or data necessary for executing the workpiece shape measurement program.
The input unit 31 inputs operating conditions of the workpiece shape measuring system 100 from the terminal device 80 . The operating conditions include a plurality of operating modes, such as a mode in which the center position measuring section 41 measures the center position and a mode in which the shape measuring section 42 measures the shape. The movement control unit 34 relatively moves the displacement sensor 2 in the movement directions X and Y with respect to the workpiece 90 along a movement path predetermined for each operation mode according to the input operation condition (operation mode).

The output unit 32 outputs the shape measurement result to the terminal device 80 . The terminal device 80 displays the output result from the output section 32 on its display.
The displacement sensor control section 33 controls the operation of the displacement sensor 2 . The displacement sensor control section 33 may be implemented by the control circuit 25 of the displacement sensor 2 .
The movement control unit 34 controls the operation of the movement mechanism 5 and controls the position of the displacement sensor 2 with respect to the workpiece 90 in the movement direction. The movement control section 34 has a first movement control section 34 a that controls the operation of the first movement mechanism 6 and a second movement control section 34 b that controls the operation of the second movement mechanism 7 .

The first movement control unit 34a refers to the detection result of the first encoder 6e and controls the operation of the first movement actuator 6c according to the input operating conditions. Thereby, the first movement control section 34 a controls the position of the displacement sensor 2 in the first movement direction X with respect to the workpiece 90 .
The second movement control section 34b refers to the detection result of the second encoder 7d and controls the operation of the second movement actuator 7b according to the input operating conditions. Thereby, the second movement control section 34b controls the position of the displacement sensor 2 with respect to the workpiece 90 in the second movement direction Y. As shown in FIG.

The displacement acquisition unit 35 sequentially acquires the measurement results derived by the measurement unit 26 from the displacement sensor 2 . The position acquisition unit 36 sequentially acquires detection results of the position of the displacement sensor 2 in the moving direction with respect to the workpiece 90 from the position sensor 8 . The position acquisition unit 36 acquires the detection result from the first position sensor 9 (first linear scale 9A) and the second position sensor 10 (second linear scale 10A). and a second position acquisition unit 36b.

The displacement sensor 2 is moved in the movement directions X and Y with respect to the workpiece 90 by the movement control section 34 . The displacement acquisition unit 35 and the position acquisition unit 36 successively acquire measurement results or detection results while the position of the displacement sensor 2 in the moving directions X and Y with respect to the workpiece 90 changes moment by moment. A sampling period is not particularly limited, and is, for example, 5 milliseconds.
The position synchronization unit 37 associates the measurement results sequentially acquired by the displacement acquisition unit 35 with the detection results sequentially acquired by the position acquisition unit 36 . Thereby, one measurement result derived at a certain timing is associated with the detection result detected at the same timing. It is possible to specify where the displacement sensor 2 was positioned with respect to the workpiece 90 in the movement direction when the displacement measurement result was derived.

The specific method of this association, linking, or synchronization is not particularly limited. The measurement result or detection result may be output to the workpiece shape measuring apparatus 1 with a time stamp indicating the measurement time or detection time. When the measurement result or detection result is acquired by the workpiece shape measuring device 1, a time stamp indicating the time of acquisition may be added. The position synchronization unit 37 may refer to the time stamps to associate measurement results and detection results with time stamps indicating the same period.

The correction section extraction unit 38 refers to the measurement result and the detection result correlated with each other by the position synchronization unit 37, and the measurement result continuously increases or decreases according to the position change in the moving directions X and Y. is extracted as a correction section α including the boundary 95 between the surface 91 and the concave portion 92 or convex portion 93 provided on the surface 91 of the workpiece 90 .
The correction section 39 derives the position of the boundary 95 inside the correction section α extracted by the correction section extraction section 38 . The correction unit 39 corrects the measurement result so that the displacement abruptly changes at the boundary 95 .

The central position measuring unit 41 measures the central position of the concave portion 92 or the convex portion 93 when viewed in the facing direction Z based on the position of the boundary 95 derived by the correcting portion 39 . The shape measuring unit 42 measures the shape of the concave portion 92 or the convex portion 93 when the workpiece 90 is viewed in the facing direction Z based on the position of the boundary 95 derived by the correcting portion 39 . The determination unit 43 determines quality of the work 90 based on the measurement results of the center position measurement unit 41 and/or the shape measurement unit 42 .

(correction)
Regarding the "section where the measurement result continuously increases or decreases (continuous change section)", at the right position in FIG. Stable measurement results can be derived. At the left position in FIG. 5, the spot light s is irradiated onto the bottom surface of the recess 92, and the measurement unit 26 can derive a stable measurement result corresponding to the distance Z92. The spotlight s passes through the boundary 95 while the displacement sensor 2 moves from the right position to the left position.

FIG. 6A is a composite of plan view and graph. The plan view of FIG. 6A shows the periphery of the recess 92 of the workpiece 90, and the recess 92 is blacked out. Note that the spot diameter φs is smaller than the diameter φ92 of the concave portion 92 .
Please refer to the spot light s1 shown in the upper part of the plan view of FIG. 6(A). If the boundary 95 is included in the spotlight s1 (that is, within the irradiation range of the light L), the spotlight s1 is projected onto an area A91 (white area) irradiated on the surface 91 and inside the recess 92. A region A92 (a black-painted region) where the light is irradiated is divided into two. In this case, the measurement unit 26 derives a single value as the measurement result, and the displacement sensor 2 outputs the derived single value to the work shape measuring device 1 as the measurement result.

In this embodiment, the displacement sensor 2 outputs the average value of the displacements at a plurality of locations within the irradiation range of the light L irradiated onto the surface 91 of the workpiece 90 as the measurement result. The measurement unit 26 may derive a single measurement result according to the area ratio of the two regions A91 and A92. The measurement unit 26 multiplies the displacement measurement result (corresponding to the distance Z91) in the area A91 by the area ratio of the area A91, and the displacement measurement result in the area A92 (corresponding to the distance Z92) to the area A92 You may derive the average value with the value which multiplied the area ratio of as a measurement result.

Next, refer to the plurality of spot lights s(x1) to s(x5) shown in the center of the plan view of FIG. 6(A) and the graph of FIG. 6(A). Here, it is assumed that the displacement sensor 2 is moving in the first movement direction X while the optical axis of the displacement sensor 2 is kept at the same position as the center of the concave portion 92 in the second movement direction Y.
Reference symbols “x1” to “x5” are positions of the optical axis of the displacement sensor 2 in the first moving direction X. As shown in FIG. The reference “s(x1)” is the spot light when the optical axis is positioned at the position x1 in the first movement direction X. FIG. Note that the optical axis coincides with the center of the spot light s. The reference “z(x1)” is a single measurement result derived by the measurement unit 26 when the optical axis is positioned at the position x1 in the first movement direction X. FIG. s(x1) and z(x1) are applied mutatis mutandis to the reference sign representing the spot light and measurement result at that position by replacing "x1" with a symbol representing another position.

The spot light s(x1) circumscribes the boundary 95. Light spot s(x3) inscribes boundary 95 at the same point of contact as light spot s(x1). Position x2 is the midpoint between positions x1 and x3, and boundary 95 passes through the center of spot light s(x2). The light spot s(x4) is inscribed with the boundary 95 at the contact point on the opposite side of the light spot s(x3). Light spot s(x5) circumscribes boundary 95 at the same point of contact as light spot s(x4).

When the optical axis of the displacement sensor 2 is positioned at the position x1, the entire surface 91 is irradiated with the spot light s(x1) (A91: 100%). Therefore, the measurement unit 26 derives a value corresponding to the distance Z91 as the measurement result z(x1). This is the same when the optical axis is positioned to the left of position x1 and when the optical axis is positioned to the right of position x5 and x5.
When the optical axis of the displacement sensor 2 is located at the position x3 or the position x4, the entire area of the spot light s(x3) is irradiated onto the bottom surface of the concave portion 92 (A92: 100%). Therefore, the measurement unit 26 derives a value corresponding to the distance Z92 as the measurement result z(x3). The same is true when the optical axis is positioned between positions x3 and x4.

The boundary 95 continues to be included in the spot light s while the displacement sensor 2 moves from position x1 to position x3. The area ratio of the region A91 continuously decreases from 100% to 0%, and conversely, the area ratio of the region A92 continuously increases. Accordingly, the measurement result continuously increases from the value corresponding to the distance Z91 to the value corresponding to the distance Z92. The same is true while the displacement sensor 2 moves from the position x4 to the position x5. The measurement result continuously decreases from the value corresponding to the distance Z92 to the value corresponding to the distance Z91.

This continuously increasing or decreasing section (continuously changing section) corresponds to the distance that the displacement sensor 2 moves from the position x1 to the position x3 in the first movement direction X. As shown in FIG. It also corresponds to the distance that the displacement sensor 2 moves from the position x4 to the position x5 in the first moving direction X.
As shown in FIG. 6B, the boundary 95 is not inclined with respect to the opposing direction Z in this example. Therefore, the dimension of the continuously changing section is equal to the spot diameter φs.

FIG. 6(B) shows the cross section of the workpiece 90 as well as the slice data obtained based on the measurement result by a two-dot chain line. A portion where a two-dot chain line appears indicates an error in the measurement result with respect to the actual shape. In the actual cross-sectional shape, the surface 91 and the bottom surface of the recess 92 are connected in the opposing direction Z via the inner peripheral surface of the recess 92 at the position x2. On the other hand, in the slice data based on the measurement result, the surface 91 and the bottom surface of the concave portion 92 smoothly connect from the position x1 to the position x3.

In the examples shown in FIGS. 7(A) and 7(B), the boundary 95 is inclined with respect to the facing direction Z. The light spot s(x11) contacts the edge of the opening on the surface 91 of the recess 92, and the light spot s(x13) contacts the periphery of the bottom surface of the recess 92 internally. Note that the position x12 is the midpoint between the positions x11 and x13, and a wide boundary 95 is included in the spot light s(x12).

The continuously changing section is the section from position x11 to position x13. The continuously changing section is longer than the spot diameter φs. That is, the continuous change section in this example is longer than when there is no slope (see FIG. 6A). The measurement result changes more gently in the continuous change section than when there is no inclination (see FIG. 6B).
If the spot diameter φs is small, the continuously changing section can be reduced as much as possible, and the error with respect to the actual shape of the slice data can be suppressed as much as possible. However, even if the spot diameter φs is small, if the tolerance of the concave portion 92 is small, high measurement accuracy may be required in the inspection work.

In the workpiece shape measuring apparatus 1 according to the present embodiment, in order to meet such a request, the correction unit 39 corrects the measurement result within the continuously changing section, thereby correcting the shape of the workpiece 90, particularly the concave portion 92 or the convex portion 93. and the surface 91 are accurately measured.
FIGS. 8A and 8B, and FIGS. 9A and 9B are explanatory diagrams of the processing executed in the correction section extraction section 38 and the correction section 39. FIG. Here, the position of the displacement sensor 2 with respect to the workpiece 90 in the second movement direction Y is fixed, and the displacement sensor 2 moves at a constant speed in the first movement direction X with respect to the workpiece 90 .

In FIG. 8A, 14 measurement results sequentially acquired at predetermined intervals δx during movement from position x21 to position x34 are associated with the position in the first movement direction X by the action of the position synchronization unit 37. It is This predetermined interval δx is a value obtained by multiplying the measurement cycle and the detection cycle by the moving speed of the displacement sensor 2 . The predetermined interval δx is determined in advance in consideration of required measurement accuracy, and is, for example, 1 to 20 μm.

The correction section extraction unit 38 extracts continuous change sections. For example, the correction section extracting unit 38 subtracts the measurement result z(xk-1) corresponding to the previous position xk-1 from the measurement result z(xk) corresponding to a certain position xk to obtain the measurement result. Calculate the amount of change. The correction interval extracting unit 38 determines whether there is a continuous change interval based on whether the positive change amount continues or whether the negative change amount continues.

The correction section extraction unit 38 extracts a continuous change section longer than a predetermined distance as a correction section α. The predetermined distance is determined in advance based on the spot diameter φs of the light with which the workpiece 90 is irradiated. Conversely, the correction section extraction unit 38 does not extract a continuous change section having a spot diameter less than φs as the correction section α. This is because it is considered that such a continuously changing section merely measures the displacement of the surface 91 of the workpiece 90 which was microscopically non-flat. In this embodiment, nine times the predetermined interval δx corresponds to the predetermined distance.

In the example shown in FIG. 8(A), since the amount of change is zero in the section from position x21 to x23 and the section from position x32 to x34, the corrected section extraction unit 38 treats these two sections as continuous change sections. judge not. Since the amount of change continues to be a positive value in the section from position x23 to x32, the corrected section extraction unit 38 determines that the section is a continuous change section. The dimension of the section in the first moving direction X is equal to the predetermined distance. Therefore, the correction section extraction unit 38 extracts this continuous change section as the correction section α.

The correction unit 39 derives the center of the correction section α as the position xc of the boundary 95 . At this time, the correction unit 39 derives the dimension of the boundary 95 in the movement direction according to the dimension of the correction section α.
The correction unit 39 derives the dimension of the boundary 95 in the moving direction by subtracting the predetermined distance (corresponding to the spot diameter φs) from the dimension of the correction section α. In the examples shown in FIGS. 8A and 8B, as in FIG. 6A, the dimension W95 of the boundary 95 is zero, but this subtraction allows the dimension W95 of the boundary 95 to be accurately measured .

The correction unit 39 sets the position xc of the boundary 95 between the first end xa (position x23) and the second end xb (position x32) of the correction section α. In the example shown in FIG. 8A, the position xc of the boundary 95 having no width is set at one point between the positions x27 and x28.
According to another method, the correction unit 39 may obtain a first end displacement value z(xa) that is the measurement result of the displacement at the first end xa and a second end displacement value z(xa) that is the measurement result of the displacement at the second end xb. Calculate the average value with z(xb). In this example, the first end displacement value z(xa) is a value (for example, 10 mm) corresponding to the distance Z91, and the second end displacement value z(xb) is a value (for example, 20 mm) corresponding to the distance Z92. ), and the average value of these is 15 mm. The correction unit 39 refers to the measurement results associated with the positions and derives the positions corresponding to the average values. In this example, the measurement result z(x27) at the position x27 is 14 mm, and the measurement result z(x28) at the position x28 is 16 mm. , is set to a point between the positions x27 and x28.

The correction unit 39 corrects the measurement result so that the displacement abruptly changes at the position xc of the boundary 95 . More specifically, the correction unit 39 corrects the measurement result so that the displacement changes from the first end displacement value z(xa) to the second end displacement value z(xb) at the boundary position xc. Then, the correction unit 39 corrects the measurement result so that the displacement changes at the first end displacement value z(xa) in the first section α1 from the first end xa to the position xc of the boundary 95 in the correction section α. do. The correction unit 39 corrects the measurement result so that the displacement changes at the second end displacement value z(xb) in the second section α2 from the boundary position xc to the second end xb in the correction section α.

The sum of the dimension of the first section α1 and the dimension of the second section α2 corresponds to the predetermined distance (corresponding to the spot diameter φs).
In FIG. 8A, the measurement result after correction is indicated by a thick line. The measurement result, which changes gently within the correction interval α, is corrected to change sharply at the position xc of the boundary 95 . The slice data based on the corrected measurement results are closer to the actual shape than before the correction.

Next, in the examples shown in FIGS. 9A and 9B, the boundary 95 is inclined and has a width as in FIG. 7A. In FIG. 9A, 16 measurement results sequentially acquired while moving from position x41 to position x56 are associated with the position in the first movement direction X by the action of the position synchronization unit 37 .
In the same manner as described above, the correction section extraction unit 38 extracts a continuous change section longer than a predetermined distance as a correction section α. In the example shown in FIG. 9A, since the amount of change is zero in the section from position x41 to x43 and the section from position x54 to x56, the correction section extracting unit 38 considers these two sections to be continuous change sections. judge not. Since the amount of change continues to be a positive value in the section from position x43 to x54, the correction section extraction unit 38 determines that the section is a continuous change section. The dimension of the section in the first moving direction X is longer than the predetermined distance. Therefore, the correction section extraction unit 38 extracts this continuous change section as the correction section α.

The correction unit 39 derives the center of the correction section α as the position xc of the boundary 95 in the same manner as described above. The correction unit 39 derives the dimension W95 of the boundary 95 in the moving direction by subtracting the above-described predetermined distance (corresponding to the spot diameter φs) from the dimension of the correction section α. This subtraction allows the dimension W95 of the boundary 95 to be measured with high accuracy.
The correction unit 39 sets the position xc of the boundary 95 between the first end xa (position x23) and the second end xb (position x32) of the correction section α. In the example shown in FIG. 9A, the center of the border 95 having a width is set at one point between the positions x48 and x49. A first boundary end of the boundary 95 is set at a point that is half the dimension W95 away from the center to the first end xa. A second boundary end of the boundary 95 is set at a point that is half the dimension W95 away from the center to the second end xb. In this example, the position xc of the boundary 95 has a range from the first boundary end to the second boundary end.

The correction unit 39 corrects the measurement result so that the displacement changes from the first end displacement value z(xa) to the second end displacement value z(xb) at the position xc of the boundary 95 . For example, the correction unit 39 sets the displacement at the first boundary end of the boundary 95 to the first end displacement value z(xa), and sets the displacement at the second boundary end of the boundary 95 to the second end displacement value z(xb ), and the measurement result is corrected so that the displacement changes linearly from the first end displacement value z(xa) to the second end displacement value z(xb) within the position xc of the boundary 95 .

Further, the correction unit 39 defines the first section α1 from the first end to the first boundary end of the boundary 95, and the second section α2 from the second boundary end of the boundary 95 to the second end xb. In the first section α1, the measurement result is corrected to the first end displacement value z(xa), and in the second section α2, the measurement result is corrected to the second end displacement value z(xb).
In FIG. 9A, the corrected measurement result is indicated by a thick line. The measurement result, which changes gently within the correction interval α, is corrected to change sharply at the position xc of the boundary 95 . The slice data based on the corrected measurement results are closer to the actual shape than before the correction.
In the above description, it is assumed that the displacement sensor 2 relatively moves in the first moving direction X. FIG. When the displacement sensor 2 relatively moves in the second moving direction Y, and when relatively moving in a moving direction having both components of the first moving direction X and the second moving direction Y, the position of the boundary 95 and its It is possible to accurately measure the shape of the periphery.

(Center position/shape measurement)
The operation of the work shape measuring system 100 with improved shape measurement accuracy near the boundary 95 as described above will be described below in accordance with the procedure of the work shape measuring method shown in FIG.

First, the workpiece 90 is positioned and supported by the workpiece support device 3 (S1). Installation of the workpiece 90 may be performed manually, or may be performed automatically by a workpiece transfer robot (not shown). As a result, the suction holes 92b of the work 90 are supported by the work supporting device 3 in a posture forming a matrix with the first movement direction X as the row direction and the second movement direction Y as the column direction.

Then, the input unit 31 inputs the operating conditions from the terminal device 80 (S2). The operating conditions are configured by a combination of options such as what is to be measured and what is to be measured among the measurement targets.
Here, as an example, the operating condition is that the input unit 31 measures the center positions of the suction holes 92b1 to 92b4 at the four corners of the many suction holes 92b formed in the workpiece 90 and the shapes of the two mounting holes 92a. is input (see FIGS. 11 to 13).

Next, the movement control unit 34 causes the displacement sensor 2 to move relative to the workpiece 90 along the predetermined movement path stored in the storage unit 30 according to the operating conditions (S3). During this relative movement, the displacement sensor control section 33 causes the displacement sensor 2 to measure the displacement of the surface 91 (S4). The storage unit 30 stores in advance a plurality of patterns of the movement paths 60 and 70 (see FIG. 11) of the displacement sensor 2 with respect to the workpiece 90 in correspondence with the input operating conditions.

As shown in FIGS. 11 and 12, the movement path 60 is used for measuring the center position. The movement path 60 is formed so as to form a cross at the concave portion 92 (suction hole 92b) to be measured. The moving path 60 is composed of a horizontal path 61 extending linearly in the first moving direction X and a vertical path 62 extending linearly in the second moving direction Y. The two paths 61 and 62 are perpendicular to each other within the measurement object. do. The intersection of the two paths 61 and 62 is set so as to pass through the center of the object to be measured in an ideal state. deviate from However, since installation errors and molding errors are very small, the intersection of the two paths 61 and 62 falls within the object of measurement when viewed in the opposite direction Z. FIG.

The movement control unit 34 moves the displacement sensor 2 in the first movement direction X with respect to the workpiece 90 from the start point P61S of the horizontal path 61 to the end point P61E of the horizontal path 61. Next, the displacement sensor 2 is relatively moved from the end point P61E of the horizontal path 61 to the start point P62S of the vertical path 62 . Next, the displacement sensor 2 is relatively moved in the second movement direction Y with respect to the workpiece 90 from the start point P62S of the vertical path 62 to the end point P62E of the vertical path 62 .

As shown in FIGS. 11 and 13, the movement path 70 is used for shape measurement. In this example, the movement path 70 is composed of a plurality of horizontal paths 71 extending in the first movement direction X, and the plurality of horizontal paths 71 are spaced apart from each other by a minute intermittent movement amount δy in the second movement direction Y are arranged in The moving path 70 has a size in the first moving direction X (the length of the horizontal path 71) and a size in the second moving direction Y (the number of the horizontal paths 71) so as to cover the entire measurement object when viewed in the opposing direction Z. is determined.

The movement control unit 34 relatively moves the displacement sensor 2 with respect to the workpiece 90 toward the first side (for example, left side) in the first movement direction X along a certain horizontal path 71 . Next, the movement control unit 34 moves the displacement sensor 2 relative to the workpiece 90 in the second movement direction Y by the intermittent movement amount δy. Next, the movement control unit 34 moves the displacement sensor 2 relative to the workpiece 90 toward the second side (eg, right side) in the first movement direction X along the next horizontal path 71 . Next, the movement control unit 34 moves the displacement sensor 2 relative to the workpiece 90 in the second movement direction Y by the intermittent movement amount δy. This series of operations is repeated until the displacement sensor 2 finishes moving along the movement path 70 .

The position acquisition unit 36 sequentially acquires detection results of the relative position of the displacement sensor 2 with respect to the workpiece 90 (S5), and the displacement acquisition unit 35 sequentially acquires measurement results of displacement of the surface 91 (S6). The position synchronization unit 37 associates the measurement results sequentially acquired by the displacement acquisition unit 35 with the detection results sequentially acquired by the position acquisition unit 36 (S7).
Next, the correction section extractor 38 extracts the correction section (S8), and the correction section 39 derives the position of the boundary 95 within the correction section (S9). In this example, in FIGS. 12 and 13, portions extracted as correction sections on the movement paths 60 and 70 are indicated by white circle marks (◯). The locations extracted as correction sections are locations where the movement paths 60 and 70 intersect the boundary 95 when viewed in the opposing direction Z. FIG.

As shown in FIG. 12, the horizontal path 61 has a constant position y61 in the second movement direction Y. The lateral path 61 intersects the boundary 95 at two points P95x1 and P95x2. Although the measurement result of the displacement changes gently around these two points P95y1 and P95y2, the correction unit 39 accurately adjusts the positions xc1 and xc2 of the two points P95x1 and P95x2 in the first moving direction X by the above-described method. measure.

The vertical path 62 has a constant position x62 in the first moving direction X. As shown in FIG. The vertical path 62 intersects the boundary 95 at two points P95y1 and P95y2. Although the measurement result of the displacement changes gently around the two points P95y1 and P95y2, the correction unit 39 accurately adjusts the positions yc1 and yc2 of the two points P95y1 and P95y2 in the second moving direction Y by the above-described method. measure.
As shown in FIG. 13, each lateral path 71 intersects the boundary 95 at two points P95. The correction unit 39 accurately measures the position in the first movement direction X at each point P95.

Next, the center position measurement unit 41 derives the center position C92 of the suction hole 92b to be measured based on the boundary positions xc1, xc2, yc1, and yc2 derived by the correction unit 39 (S10).
As shown in FIG. 12, first, the central position measuring unit 41 measures the position x61C in the first movement direction X between the midpoint P61C of two points P95x1 and P95x2 on the horizontal path 61, two points P95y1 on the vertical path 62, A position y62C in the second moving direction Y of the midpoint P62C of P95y2 is measured. Since the midpoint P61C is the midpoint of the chord extending in the first moving direction X, the position x61C in the first moving direction X is equivalent to the position in the first moving direction X of the center position. Since the midpoint P62C is the midpoint of the chord extending in the second movement direction Y, its position y62C in the second movement direction Y is equivalent to the position in the second movement direction Y of the center position C92. The center position measuring unit 41 sets the measured position x61C to the position of the center position C92 in the first moving direction, and sets the measured position y62C to the position of the center position C92 in the second moving direction Y.

Next, the shape measuring unit 42 measures the shape of the mounting hole 92a to be measured based on the position of the boundary derived by the correcting unit 39 (S11).
As shown in FIG. 13, the shape measuring unit 42 derives the outline of the boundary 95 when viewed in the facing direction Z by connecting the derived positions of the boundary in sequence. The shape measuring unit 42 may connect the boundaries with curved lines or straight lines.

The shape measuring unit 42 may measure the total distance of the contour lines, that is, the perimeter of the boundary 95 . The shape measurement unit 42 may derive the area of the entire shape of the measurement target. When the boundaries are connected by straight lines, the overall shape of the object to be measured becomes a shape in which a plurality of trapezoids having the height of the intermittent movement amount δy are arranged in the second movement direction Y, and the area can be easily derived. be able to.
Next, the determination unit 43 determines whether the quality of the workpiece 90 is good or bad based on the measurement result of the center position or shape (S12). For example, the determination unit 43 derives the amount of deviation from the measured ideal value of the center position, and determines whether or not the amount of deviation is less than a predetermined allowable value. For example, the determination unit 43 derives a difference between the measured area of the shape and the ideal value, and determines whether the difference is less than a predetermined allowable value. For this determination, the storage unit 30 may store ideal values and allowable values in advance.

Next, the output unit 32 outputs the operating conditions and the corresponding results to the terminal device (S13). In this example, the output unit 32 outputs to the terminal device 80 the measurement results of the center positions C92 of the suction holes 92b at the four corners, the measurement results of the shapes of the two mounting holes 92a, and the quality determination results based on these measurement results. do. The worker can view the output result by displaying it on the display of the terminal device.
In this embodiment, the position of the boundary 95 is measured with high accuracy, and the center position and shape are measured based on the measurement result. Therefore, the center position and shape can be measured with high accuracy, so that the quality can be determined with high accuracy. It is possible to support the labor saving of the inspection work of workers.

(Modification)
Although the embodiments of the present invention have been described so far, the above configurations can be appropriately changed, added and/or deleted within the scope of the present invention.

In the above-described embodiment, the contour line of the boundary 95 of the measurement object of the center position and shape is circular when viewed in the opposite direction Z, but even if the measurement object has another shape, the center position and shape Shape can be measured.
For example, as shown in FIGS. 14A and 14B, even if the concave portions 92A and 92B are square, the movement path 60 can be applied to measure the center positions C92A and C92B. Even if the concave portion 92C is rectangular as shown in FIG. 14(C) or if the concave portion 92D is a regular polygon (for example, a pentagon) as shown in FIG. Center positions C92C and C92D can be measured. For example, as shown in FIG. 15A, even if the concave portion 92A is square, the shape can be measured by applying the moving path 70. FIG.

In the above-described embodiment, when measuring the shape, a moving path composed of a plurality of horizontal paths extending parallel to the first moving direction X is used, but the moving path when measuring the shape is not limited to this.
As shown in FIG. 15B, a moving path 70A composed of a plurality of radial paths 71A radially extending from the center position of the measurement object may be applied. Although there are 12 radiation paths 71A in FIG. 15B, the number of radiation paths 71A can be appropriately changed according to the required measurement accuracy. Before applying the moving path 70A, the center position may be measured in advance by the method of the above embodiment.

In the above embodiment, the correction section is extracted and the position of the boundary 95 is derived near the midpoint between the first end and the second end of the correction section, but the method of deriving the position of the boundary 95 is not limited to this.
In the modification shown in FIG. 16, the outline of the recess 92 includes straight lines, such as a square or a semicircle. A straight boundary 95 extends in the direction perpendicular to the movement direction of the displacement sensor 2 within the light spot s and forms a chord of the circular light spot s. In this case, geometrically derive the position xc of the boundary 95 from the spot diameter φs, the position x100 of the optical axis of the spot light s, and the single measurement result z(100) corresponding to the position x100. can be done. It is assumed that the value (Z91) indicating the displacement of the surface 91 and the value (Z92) indicating the displacement of the bottom surface of the recess 92 are known in the workpiece shape measuring apparatus 1. FIG.

The ratio of the difference between the measurement result z(x100) and the value Z91 indicating the displacement of the surface 91 and the difference between the measurement result z(x100) and the value Z92 indicating the displacement of the bottom surface of the recess 92 is the irradiation of the surface 91. It is equal to the ratio of the area SA91 of the region A91 where the light is irradiated and the area SA92 of the region A92 where the concave portion 92 is irradiated. Therefore, the area ratio of the regions A91 and A92 can be derived from the single measurement result z(x100) using the known distances Z91 and Z92. From this, the area ratio of the area A92 to the area of the entire spot light s of the area SA92 can be derived.

Here, the angle formed by the line segment connecting the center x100 to the first end point of the chord (boundary 95) and the line segment connecting the center x100 to the second end point of the chord (boundary 95) is defined as the "central angle θ". . The ratio between the area of the entire spotlight s and the area SA92 of the region A92 is 1:(θ−sin θ)/2π. Therefore, the central angle θ can be derived using the area ratio derived from the measurement result z(x100).

Here, a straight line that bisects the central angle θ and passes through the center x100 is assumed. The straight line is orthogonal to the chord (boundary 95). Let P be the intersection point between the straight line and the outer edge of the spot light s on the area A91 side, and let Q be the intersection point between the straight line and the outer edge of the spot light s on the area A92 side. The ratio of the distance d from the point P to the boundary 95 and the distance e from the boundary 95 to the point Q is 1+cos(θ/2):1−cos(θ/2). Since the sum of the distance d and the distance e is the spot diameter φs, the position xc of the boundary 95 can be derived using the central angle θ derived from the measurement result z(x100).

In this case, the position xc of the boundary 95 can be derived for each measurement result taken within the continuous change interval. The correction unit 39 may specify an average value of a plurality of derivation results regarding the position xc of the boundary 95 as the position xc of the boundary 95 .
Although the shape of the mounting hole 92a whose shape is known is measured in the above-described embodiment, the shape measuring unit 42 is preferably applied to measurement of the shape of a concave portion or a convex portion whose shape is unknown.

In the above embodiment, the displacement sensor 2 moves in the first moving direction X with respect to the floor, and the workpiece 90 moves in the second moving direction Y with respect to the floor. The displacement sensor 2 may move in the second moving direction Y with respect to the floor, and the workpiece 90 may move in the first moving direction X with respect to the floor.
Although the displacement sensor 2 is of the white coaxial confocal type in the above embodiment, the displacement sensor 2 is not limited to this type.

In the above embodiment, the measurement target of the boundary, center position, and shape was the concave portion 92, but it is also applicable to the measurement of the convex portion 93.

100 work shape measuring system 1 work shape measuring device 2 displacement sensor 3 work supporting device 5 moving mechanism 6 first moving mechanism 7 second moving mechanism 8 position sensor 9 first position sensor 9A first linear scale 10 second position sensor 10A 2 linear scale 33 displacement sensor control unit 34 movement control unit 34a first movement control unit 34b second movement control unit 35 displacement acquisition unit 36 position acquisition unit 36a first position acquisition unit 36b second position acquisition unit 37 position synchronization unit 38 correction Section extraction unit 39 Correction unit 41 Center position measurement unit 42 Shape measurement units 60, 70 Movement path 90 Work 91 Surface 92 Concave portion 93 Concave portion 95 Boundary W95 (Boundary) dimension L Light s Spot light φs Spot diameter xa First end xb Second end xc (boundary) position z(xa) First end displacement value z(xb) Second end displacement value α Correction section α1 First section α2 Second section C92 Center position δy Intermittent movement amount X First movement direction Y Second moving direction Z Opposing direction

Claims (16)

1. A displacement sensor arranged opposite to the surface of the work provided with concave portions or convex portions is controlled, the displacement sensor is caused to irradiate the surface of the work with point-like light, and the surface of the work in the facing direction is detected. a displacement sensor control unit that measures displacement;
   a movement control unit that drives a movement mechanism that relatively moves the displacement sensor with respect to the workpiece in a movement direction perpendicular to the facing direction;
   a displacement acquisition unit that sequentially acquires measurement results of the displacement from the displacement sensor that is moving in the movement direction;
   extracting a correction section including a boundary between the recess or the protrusion and the surface, the section where the measurement result continuously increases or decreases according to the change in the position in the moving direction; an extractor;
   a correction section that derives the position of the boundary inside the correction section extracted by the correction section extraction section and corrects the measurement result so that the displacement abruptly changes at the boundary;
   A workpiece shape measuring device.
2. When the measurement result continuously increases or decreases by a predetermined distance or more in the moving direction, the correction section extracting unit extracts the continuously changing section as the correction section.
   The workpiece shape measuring device according to claim 1.
3. wherein the predetermined distance is predetermined based on a spot diameter of the light irradiated onto the work;
   The workpiece shape measuring device according to claim 2.
4. The correction unit derives the center of the correction section as the position of the boundary,
   The workpiece shape measuring device according to any one of claims 1 to 3.
5. The correction unit derives the dimension of the boundary in the movement direction according to the dimension of the correction section in the movement direction.
   The workpiece shape measuring device according to any one of claims 1 to 4.
6. At the boundary, the correction unit extends from a first end displacement value, which is the measurement result at the first end of the correction section, to a second end displacement value, which is the measurement result at the second end of the correction section. , correcting the measurement result so that the displacement changes;
   The workpiece shape measuring device according to any one of claims 1 to 5.
7. The correction unit is
   correcting the measurement result so that the displacement changes at the first end displacement value in a first section from the first end to the boundary in the correction section;
   correcting the measurement result so that the displacement changes at the second end displacement value in a second section from the boundary to the second end of the correction section;
   The workpiece shape measuring device according to claim 6.
8. Further comprising a center position measuring unit that measures the center position of the concave portion or the convex portion when viewed in the opposite direction based on the position of the boundary derived by the correction unit;
   The workpiece shape measuring device according to any one of claims 1 to 7.
9. A shape measuring unit that measures the shape of the concave portion or the convex portion when the workpiece is viewed in the facing direction based on the position of the boundary derived by the correction unit,
   The workpiece shape measuring device according to any one of claims 1 to 8.
10. A workpiece shape measuring device according to any one of claims 1 to 9;
    A displacement sensor arranged to face the surface of the work on which the concave portion or the convex portion is provided, irradiating the surface of the work with point-like light, and measuring the displacement of the surface of the work in the facing direction. When,
    a movement mechanism that relatively moves the displacement sensor with respect to the workpiece in a movement direction perpendicular to the facing direction;
    Work shape measurement system.
11. The displacement sensor outputs, as a measurement result, an average value of the displacements at a plurality of locations within an irradiation range of the light irradiated onto the surface of the work,
    The workpiece shape measuring system according to claim 10.
12. The displacement sensor emits light in the opposite direction, detects reflected light returning from the surface of the workpiece in the same direction as the direction in which the light is emitted, and measures the displacement of the portion irradiated with the light.
    The workpiece shape measuring system according to claim 10 or 11.
13. wherein the displacement sensor has confocal optics;
    The workpiece shape measuring system according to claim 12.
14. The movement mechanism is
    a first movement mechanism for moving the displacement sensor in a first movement direction orthogonal to the facing direction;
    a second moving mechanism for moving the workpiece in a second moving direction orthogonal to the facing direction and the first moving direction;
    The work shape measuring system according to any one of claims 10 to 13.
15. A displacement sensor arranged opposite to the surface of the work provided with concave or convex portions is controlled, and the displacement sensor is caused to irradiate the surface of the work with a point-like light, so that the surface of the work in the facing direction is controlled. A displacement sensor control step for measuring the displacement of
    a movement control step of driving a movement mechanism that relatively moves the displacement sensor with respect to the workpiece in a movement direction perpendicular to the facing direction;
    a displacement acquisition step of sequentially acquiring measurement results of the displacement from the displacement sensor moving in the movement direction;
    extracting a correction section including a boundary between the recess or the protrusion and the surface, the section where the measurement result continuously increases or decreases according to the change in the position in the moving direction; an extraction step;
    a correction step of deriving the position of the boundary inside the correction section and correcting the measurement result so that the displacement abruptly changes at the boundary;
    A workpiece shape measurement method comprising:
16. causing a computer to execute the workpiece shape measuring method according to claim 15,
    Work shape measurement program.

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