JPH09113254A - Method and device for detecting center position - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accurately measure the center position of the slit, etc., of an object to be measured with a simple constitution. SOLUTION: A non-contacting sensor 50 moved toward a position (2) inside the slit 5 of an object W to be measured from a position (1) outside the slit S and stops after the sensor 50 detects the position s1 one edge of the slit S. The detecting error of the position s1 is δ1. Similarly, the sensor 50 moves toward a position (4) inside the slit S from a position (3) outside the slit S and detects the position s2 of the other edge. The detection error of the position s2 is δ2. Since the errors δ1 and δ2 are symmetrical with respect to the center of the slit S, the position of the center of the slit S can be found accurately by only calculating the value of the middle point of the position s1 and d2 including the errors δ1 and δ2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention uses a die having minute slits such as an extrusion die for molding an aluminum die material such as a building material as an object to be measured, and the center position of the slit of the object to be measured. The present invention relates to a center position detecting method and device for detecting a center position.

[0002]

2. Description of the Related Art Generally, an aluminum mold material such as a building material, for example, a sash frame is obtained by extrusion molding. A mold is used for this extrusion molding process, but since this mold has a cross-sectional shape such as a sash frame, which is a molded product, it is formed in a slit shape. Is determined. Therefore, it is premised that the slit shape of the die is precisely processed, and the slit shape and the like are precisely measured before the die is used.

Conventionally, the slit of the mold has been measured by a measurer using a measuring instrument such as a caliper. However, the error varies from one measurer to another and the skill level is required.
Automation was desired.

Therefore, for example, a method of measuring the outer shape of the contact probe or a contact-type measuring device that moves the object to be measured up and down, left and right, and back and forth, an image processing device such as a CCD camera, and an optical sensor. Various measuring methods and measuring devices have been devised, such as non-contact type measuring methods.

[0005]

However, in the above-mentioned conventional measuring device, according to the former device using the contact probe, the contact probe or the object to be measured can be freely moved in the up, down, left and right directions. However, it is necessary to design each drive part with high accuracy because the coordinates of the three-dimensional position of the slit are measured by driving each of them at the same time. This is a method of obtaining (measuring) the coordinates of the shape, and the measurement of this point must be repeated, and high precision that does not cause an error in each measurement is required.
Also, there is a drawback in that reliability is required for each adjustment and the cost is very high.

Further, this contact probe has a structure in which it is composed of a needle-shaped thin shaft rod and a spherical contactor is formed at its tip, but if the slit position is not known in advance, Since the object to be measured may be damaged when it is inserted into the slit, it is necessary to know the slit position, for example, the edge position of the slit or the center position between the edges in advance.

This edge position can be measured by using a contact sensor that comes into contact with the object to be measured. Since this contact sensor has a certain size to ensure strength at the time of contact, the slit is When formed minutely, the detection terminal of the sensor becomes larger and the edge of the slit may not be detected. Moreover, when a non-contact sensor such as an integrated light emitting and receiving sensor is used, the change point of the detection signal can be detected as the edge position of the slit, but if the beam diameter of the projected light is large, the detection accuracy will decrease correspondingly and It may not be possible to detect a large slit.

On the other hand, in the latter case of the non-contact type such as the image processing device, the accuracy is determined by the resolution of the image processing device, but the size of the entire device becomes large and the cost becomes high, and Since only the surface shape of the object to be measured is measured, there is a drawback that it is impossible to measure the surface shape in the slit.

Therefore, in order to solve the above problems, the present invention provides a center position detecting method and apparatus capable of accurately measuring the center position of a slit or the like of an object to be measured with a simple structure. Has an aim.

[0010]

Next, means for achieving the above object will be described with reference to the drawings corresponding to the embodiments. The center position detecting method of the present invention is a center position detecting method for obtaining a center position A between both edges s1 and s2 of a recess S such as a slit formed in an object to be measured W. After the edge measuring means 50 is moved from the position outside the one edge s1 toward the inside of the recess S to detect the one edge position s1, the recess S of the object to be measured W is detected.
After the edge measuring means 50 is moved from the outside position of the other edge s2 of the other side toward the inside of the recess S to detect the other edge position s2, the one and other edge positions s1,
It is characterized in that an intermediate value of the values of s2 is obtained as the center position A of the recess S.

Further, according to the center position detecting method of the present invention, both edges s of the concave portion S such as a slit formed in the object W to be measured.
In the center position detecting method for obtaining the center position A between the s1 and the s2, the edge measuring means 50 is moved from the inside position of the concave portion S of the object W to the one edge s1 outward direction to determine the one edge position s1. After the detection, the edge measuring means 50 is moved from the position inside the recess S of the object to be measured W toward the outside of the other edge s2 to detect the other edge position s2, and then the one and other edge positions s1. , S2
It is characterized in that an intermediate value of the values of is obtained as the center position A of the recess.

Further, a convex portion Wp is formed on the object to be measured W in place of the concave portion S, the edge measuring means 50 detects both edge positions s1 and s2 of the convex portion Wp, and both edge positions s1 and s1. An intermediate value of the values of s2 can be obtained as the center position A of the convex portion Wp.

Next, the center position detecting device according to the present invention is
The bed 2A on the base 2 that holds the object to be measured W on which the concave portion S or the convex portion Wp is formed and the concave portion of the object to be measured W that is movable in the horizontal directions X and Y with respect to the bed 2A. The non-contact sensor 50 that detects both edge positions s1 and s2 of S or the convex portion Wp, and the intermediate value of the values of both edge positions s1 and s2 that the non-contact sensor 50 detects is the center position A of the concave portion S or the convex portion Wp. And an arithmetic unit for obtaining

Further, the non-contact sensor 50 is provided on a head 21 which is movable in horizontal directions X, Y and up and down directions Z with respect to the bed 2A, and the head 21 has both edges s1 of the recess S. , S2 surface is provided, and a contact probe 26 for measuring the state of the edge surface is provided, and the contact probe 26 is configured to be inserted into the recess S from the central position A obtained by the calculation unit. You can also

The slit S of the object to be measured W is placed on the bed 2A, and the non-contact sensor 50 provided on the head 21 and movable in the horizontal directions X and Y has the edge positions s1 at both ends of the slit S. s2 is detected. This non-contact sensor 50
When detecting the edge position s1 of the slit S,
Similarly, when the edge position s2 is detected, the edge position s2 is moved to the inside from the outside position of the edge position s2, detected, and stopped. Since the errors δ1 and δ2 at this time both occur inside the edge positions s1 and s2, they are symmetrical with respect to the center position A of the slit S. Therefore, the calculation unit can obtain an intermediate value of the values of these edge positions s1 and s2 as the accurate center position of the slit S, and the same calculation adds and subtracts and divides based on the detected both edge positions s1 and s2. It can be done by a simple calculation such as The center position A is used as, for example, an insertion position of the contact probe 26 for measuring the state of the surfaces of the edges s1 and s2 of the slit S.

[0016]

1 is a schematic perspective view showing an embodiment to which a center position detecting device of the present invention is applied, FIG. 2 is a side sectional view of a Y-axis table according to the embodiment, and FIG. FIG. 4 is a front view of the X-axis table and head according to the same embodiment.
[Fig. 3] is a front view of the probe according to the same embodiment.

The center position detecting device of the present invention is provided in the three-dimensional measuring device 1 shown in FIG. This three-dimensional measuring device 1
Is a base 2, a Y-axis table 9, and an X-axis table 16
The head 21, the sensor unit 25, and the like are generally configured.

First, the base 2 is installed on the anti-vibration base 3 so that the vibration from the floor surface is not transmitted. A bed 2A is fixed to the upper surface of the base 2 as shown in FIG. 1, and the bed 2A is fixed to the upper surface of the bed 2A as shown in FIG.
A pair of straight guide rails 4 that are parallel to each other and a ball screw 6 that is disposed parallel to each guide rail 4 via a bearing 5 are disposed.

Each guide rail 4 is provided with a slidable guide slider 7, and a nut 8 is screwed to the ball screw 6. The Y-axis table 9 is arranged so as to extend over the respective guide sliders 7 and nuts 8, and the Y-axis table 9 is moved to the bed by a rotation driving motor 10 connected to the ball screw 6. It is movable in the front-back direction (Y direction in the drawing) horizontal to 2A.

A work table 11 is provided on the upper surface of the Y-axis table 9. This work table 11
Has a smooth upper surface, on which an object to be measured W to be measured by the measuring device 1 is placed. Both ends in the moving direction of the Y-axis table 9 are covered with a bellows 12 for dust protection.

Next, on the bed 2A on the base 2, as shown in FIG.
As shown in FIG. 5, a gate bridge 13 is vertically erected and fixed so as to extend above the Y-axis table 9 in a direction orthogonal to the moving direction of the Y-axis table 9.

On the front side of the horizontal portion of the upper portion of the gate-shaped bridge 13, as shown in FIG. 3, a pair of parallel straight guide rails 14 of the same construction as the Y-axis table 9 are provided.
Ball screws 15 arranged parallel to the guide rails 14 are provided so as to be horizontal and orthogonal to the moving direction of the Y-axis table 9.

Then, the X-axis table 16 is moved through a guide slider (not shown) slidably provided on each guide rail 14 and a nut (not shown) screwed to the ball screw 15. The plate surface is set as vertical,
That is, the X-axis table 16 is movable in the left-right direction (X direction in the drawing) horizontal to the bed 2A by the rotation driving motor 17 connected to the ball screw 15.

Further, as shown in FIG. 3, a pair of parallel X-axis tables 16 having the same construction as the Y-axis table 9 and the X-axis table 16 are provided on the plate surface of the movable X-axis table 16 on the vertical front side. The straight guide rails 18 and the ball screws 19 arranged parallel to the respective guide rails 18 are orthogonal to each other with respect to the moving directions of the Y-axis table 9 and the X-axis table 16. It is provided perpendicular to the plate surface.

A board that constitutes the head 21 is provided through a guide slider (not shown) slidably provided on each guide rail 18 and a nut (not shown) screwed to the ball screw 19. 20 is provided with its plate surface vertical, that is, the substrate 20 is moved in a vertical direction (Z direction in the drawing) perpendicular to the substrate 20 by a rotation driving motor 22 connected to a ball screw 19. It is free.

The X-axis table 16 and the head substrate 2
On the movement locus of 0, bellows 23 and 24 for dust protection are provided respectively.

As shown in FIGS. 1 and 4, a rectangular head 21 is provided on the substrate 20, and the bottom portion 2 is provided.
The sensor unit 25 is arranged so as to extend to the la 1a.

This sensor section 25 is used for the vertical plane probe 2.
6 and a horizontal plane probe 31, each of which is arranged in parallel as shown in FIG.
It is provided in a hanging shape on 1a.

As shown in FIG. 4, the vertical surface probe 26 is fixed so that the feeler 27 provided at the tip extends downward from the bottom portion 21a of the head 21.

In the probe 26 for the vertical surface, the base portion 27a of the feeler 27 at the tip is pivotally supported by the probe main body 28, and the tip end side of the feeler 27 is swingable, and the capacitance that changes by this swinging is generated. The probe is a lever type probe that outputs an analog signal by a frequency modulation method, and detects the change in the swing angle of the feeler 27 to measure the shape of the object to be measured W. In the case of the present embodiment. The shaft supporting portion is biased by an elastic member or the like so that the tip end side of the feeler 27 is slightly inclined with respect to the pivotally supported base 27a, and the contact surface 29 of the feeler 27 is biased by the biasing force of this elastic member. , Is in contact with the surface to be measured.

The feeler 27 has a tip portion 27b.
However, the needle 30 is made of a needle-shaped super-hard rod having a small diameter, and the contact 30 is provided at the leading end. As shown in FIGS. 5 (a) and 5 (b), the contactor 30 is formed by notching three vertical surfaces adjacent to each other on a sphere (C in FIG. 5 (a) and C in FIG. 5 (b)). The cross-sectional shape is formed into a substantially semicylindrical shape, that is, only the contact surface 29 that contacts the measurement surface of the object to be measured W has a convex curved surface shape.

The vertical plane probe 26 is provided with a rotation drive mechanism (not shown) at the base end, and the feeler tip 2
The convex spherical contact surface 29 of 7b can be controlled to face a desired direction.

Next, the horizontal plane probe 31 is juxtaposed with the vertical plane probe 26 as shown in FIG.
It is provided in.

In the horizontal plane probe 31, the probe body 32 is fixed to the straight slide rail 34 via a fixture (not shown), and the substrate 20 of the head 21 is fixed.
Is slidably provided on a guide block 35 disposed on the bottom 21a of the head 21. The sliding direction is the same direction parallel to the moving direction of the head 21, that is, the vertical direction. On the other hand, the probe 31 is provided so as to be vertically movable.

Then, as shown in FIG. 4, a bracket 36 protruding horizontally is provided on the slide rail 34.
Is provided, and the fastening screw 3 is provided through a vertically elongated guide slit (not shown) formed on a side portion of the head 21.
7 is screwed, and the vertical position of the horizontal plane probe 31 with respect to the head 21 can be fixed.

The tip 3 of the horizontal plane probe 31
In the contactor 38 of 1a, the tip surface 39 serving as the bottom surface is formed in a spherical shape, and the contactor 38 is formed by the probe main body 3
2 is made up of a plunger type probe that can be moved back and forth within a predetermined range in the longitudinal direction, and the capacitance that changes due to this forward and backward movement is output as an analog signal by a frequency modulation method. This is to detect and measure an advance / retreat distance (displacement) within a predetermined range.

The horizontal and vertical probes 26 and 31 are connected to a control unit (not shown) from the base end via a cable 40, and the numerical values of the respective detected values and the displacements based on these numerical values are displayed. Graphic figures are displayed on the display.

Although not shown, the rotary position of a rotary encoder or the like arranged in the motors 10, 17, and 22 as drive sources is provided in each of the above-mentioned Y-axis table 9, X-axis table 16, and head 21. A sensor is arranged and can be converted into each position coordinate, and three-dimensional coordinates of vertical, horizontal, and height based on the bed 2A fixed on the base 2 are measured, and each unit 9 , 16 and 21, a control unit for driving and controlling, a console K (see FIG. 1) for instructing these driving from the outside, measured three-dimensional coordinates, and each measured value obtained by each probe 26, 31 are stored. A storage means for performing the operation is connected.

Next, the edge measuring means used in the center position detecting device of the present invention comprises a non-contact sensor 50. As shown in FIG. 4, the non-contact sensor 50 is attached downward of a mounting bar 50c extending from the bottom portion 21a of the head 21. The arrangement position of the non-contact sensor 50 is the central position (P) of a straight line virtually connecting the arrangement positions of the vertical plane probe 26 and the horizontal plane probe 31.
1 = P2). The virtual straight line is located on the X-axis direction and coincides with the moving direction of the head 21.

The non-contact sensor 50 is composed of a general-purpose fiber sensor. To explain the outline, the light emitting / receiving unit (not shown) causes measurement light from an LED or the like to enter the optical fiber 50a from the light emitting unit. The measurement light is condensed and emitted from the condenser lens 50b of the non-contact sensor 50 onto the object to be measured W with a predetermined beam diameter. The reflected light is branched and received by the light receiving element of the light receiving portion of the light emitting / receiving unit via the optical fiber 50a. This non-contact sensor 50
The condenser lens 50b located at the lower end of is located above the contact 30 of the vertical surface probe 26 and does not prevent the contact 30 from being inserted into the slit S.

The light projecting / receiving unit detects the edge position of the slit S, which will be described later, based on the change in the light intensity of the reflected light detected by the light receiving unit, and the arithmetic unit calculates the intermediate value of the values of both edge positions. The center position A is calculated. The non-contact sensor 50 can be moved in the X direction with respect to the measured object W by the movement of the head 21, and can be relatively moved in the Y axis direction of the measured object W by the movement of the Y axis table 9.

Next, a method of measuring the object to be measured W by the three-dimensional measuring apparatus 1 having the above-mentioned configuration will be described in the order of each step.

The object W to be measured is an extrusion mold W for molding an aluminum mold material such as a building material as shown in FIG.
As shown in FIG. 6B, a horizontal plane WH and this horizontal plane WH
It has a shape including a slit S which is a mouthpiece and is composed of a vertical surface WV that is at a right angle to.

Then, the mold W, which is the object to be measured, is placed on the work table 11 of the measuring apparatus 1.

The front-rear direction which is the moving direction of the Y-axis table 9 is the Y-axis direction, the left-right direction which is the moving direction of the X-axis table 16 is the X-axis direction, and the vertical direction which is the moving direction of the head 21 is the Z-axis direction. In the Y-axis direction, the front direction is + Y direction, the rear direction is -Y direction, and the left direction in X-axis direction is + X direction.
Direction, rightward direction is -X direction, upward direction in Z axis direction is +
The Z direction and the downward direction will be described as the −Z direction (FIG. 1,
2 and 3).

(1) Measurement of Horizontalness of Horizontal Surface WH of Mold W (See FIG. 7) First, the motor 10 on the bed 2A is driven to move the Y-axis table 9 and fixed on the Y-axis table 9. The metal mold W to the sensor portion 25 extending from the head bottom portion 21a.
Move it to the position just below.

At this time, in the sensor section 25, the horizontal plane probe 31 is moved by the slide rail 34 so as to be positioned immediately before the horizontal plane WH (arrow line in FIG. 4), and the fastening screw 3 is inserted.
Then, the contactor tip surface 39 of the horizontal plane probe 31 is extended below the contactor 30 of the vertical plane probe 26 (one-dot chain line in FIG. 4).

Next, the Y-axis table 9 and the X-axis table 1
6 respectively to drive the front terminals 3 of the horizontal plane probe 31.
8 is stopped right above the starting position of the horizontal plane WH for measuring the mold W (position A in FIG. 7A). The positioning of the probe 31 and the mold W by the Y-axis table 9 and the X-axis table 16 may be performed by setting the positions in advance and automatically driving the motors 10 and 17, or manually. You may move by operation and perform position adjustment.

Next, the head 21 is moved in the downward (-Z) direction to bring the contactor tip surface 39 of the horizontal surface probe 31 into contact with the horizontal surface WH of the mold W and to slightly retract the contactor 38. Stop, and the vertical, horizontal, and height positions based on the bed 2A at this position, that is, the three-dimensional coordinate values in the X-, Y-, and Z-axis directions are displayed on the Y-axis table 9 and the X-axis table 16. The measurement is performed by each sensor provided in the head 21, and the displacement value, which is the value in the height direction of the detection value of the probe 31, is corrected to 0 (position B in FIG. 7A). At this time, the displacement value which is the detection value of the horizontal plane probe 31 is displayed on the display as shown in FIG. 7B by the control unit, and the expansion / contraction state of the contact 38 is range-displayed. .

The head 21 descends when the contact 3
8 is a position 1 to 2 mm above the horizontal plane WH of the mold W (see FIG. 7).
It may be moved manually until it reaches the (a) middle B ′ position), or the procedure may be such that the contacts 38 are brought into contact with and retracted from this position by driving by the motors 10 and 22.

Next, the Y-axis table 9 and / or the X-axis table 16 is moved manually, or by driving by the motors 10 and 17, that is, in the horizontal one-dimensional or two-dimensional direction to move the second point position. (C in FIG. 7 (a)
Each of the three-dimensional coordinate value of (point) and the displacement value is measured. At this time, the head 21 that moves in the Z-axis direction is not moved,
The contact 38 is slidably moved in a state of being in contact with the horizontal surface of the mold W, and the stopped position is measured.

Then, again, manually or with the motors 10, 17
Driven by the Y-axis table 9 and / or X
The axis table 16 is moved, that is, moved in the horizontal one-dimensional or two-dimensional direction, and the position of the third point (Fig. 7 (a)).
The three-dimensional coordinate value and the displacement value of the middle D point) are measured. Also at this time, similarly to the above, the head 21 that moves in the Z-axis direction is not moved, and the contactor 38 is slidably moved in a state of being in contact with the horizontal surface WH of the mold W, and the stopped position is measured.

Further, as shown in FIG. 7B, the starting point, the second point, and the third point are not on the same straight line, and the fourth and subsequent points may be measured. Measure so that they are not on the same straight line. In addition,
The number of measurement points is 3 or more and 10 or less.

The bed 2 of the horizontal surface WH of the mold W fixed on the Y-axis table 9 is measured by the above measured values.
The horizontality with respect to A is calculated, and this is used as a correction value. This correction value is calculated and stored as an angle. After measurement,
The probe 31 is moved up by the movement of the head and moved to a position substantially above the starting point. Numerical values such as measurement values and correction values are displayed on the display and measurement points are graphically displayed.

(2) Measurement of the linearity of the horizontal surface WH of the mold W (see FIG. 8) Next, the horizontal plane probe 31 is again attached to the horizontal surface W of the mold W.
It is moved so as to come into contact with H. Next, the measurement distance, measurement pitch, and measurement direction of the horizontal plane probe 31 are set. This setting is performed by input means such as a keyboard, the measurement distance is the length on the horizontal plane WH to be measured, and the measurement direction is four types of + direction or − direction in the Y-axis direction or the X-axis direction with respect to the bed 2A. In any one of the directions, that is, on the horizontal plane WH of the mold W, the probe 31 is selected to move in a straight line. In this embodiment, +
An example of setting in the X direction will be described.

Then, the contactor 38 is slightly retracted, and the contactor 38 is stopped at the displacement position where the expanded / contracted state of the contactor 38 is approximately 0 in the range display (point A in FIG. 8A). The three-dimensional coordinate value of this position is measured, and the displacement value of this detected value is corrected to zero.

Next, the X-axis table 16 is moved in the + X direction without moving the head 21 according to the measuring distance, measuring pitch and measuring direction which are input and set from the outside.
The horizontal plane probe 31 is moved in a straight line over a desired distance, and the three-dimensional coordinate value and the displacement value between the distances are measured. Each measured value is measured at a predetermined pitch between moving distances, and the displacement value is the linearity of the horizontal plane WH of the mold W,
In other words, it is the displacement amount in the Z-axis direction with respect to the X-axis direction.

The measured values are shown as numerical values and figures in FIG.
As shown in (b), it is displayed on the display and these measurement results are stored.

After the measurement, the head 21 moves up (+ Z direction).
By moving, the horizontal plane probe 31 is lifted from the mold W (points B and C in FIG. 8A).

(3) Measurement of the linearity of the vertical surface WV in the slit S of the mold W (a) Measurement of the linearity in the vertical direction on the vertical surface WV (see FIG. 9) Next, the horizontal plane WH of the mold W is measured. The horizontal plane probe 31 to be measured is moved upward by the slide rail 34 so as to be retracted from the extended state and fixed by the fastening screw 37 at the uppermost position, and only the vertical plane probe 26 is fixed to the bottom portion 21a of the head 21. It is set so as to be in a drooping state (see FIG. 4).

In this embodiment, the slit S of the mold W to be measured has a longitudinal direction in the Y-axis direction with respect to the bed 2A and a width direction in the X-axis direction. Fixed.

The edge position and the center position of the width of the slit S are detected by the non-contact sensor 50. When the slit S is detected, the operation of detecting the edge and the center position differs depending on whether the non-contact sensor 50 is located outside or inside the slit S. For example, when the non-contact sensor 50 is located outside the slit 50, the head 21 moves the non-contact sensor 50 from the outside of the slit S toward the edge as shown in the schematic view of FIG. 12 (X-axis). direction).

When the non-contact sensor 50 moves from the position in one of the slits S in the direction of the slit S, the light receiving portion detects one edge s1 at this changed position due to a change in reflected light (for example, ON → OFF). To do. The head 21 stops upon receiving this detection, but the true edge position s
The head 21 is stopped at an inner position by an error δ1 from 1.
Is located at the X coordinate including the error δ1. The accuracy of position detection by the non-contact sensor 50 is affected by the beam diameter of the measurement light with which the object to be measured W is irradiated.
At 0, since the optical fiber is focused and irradiated, the beam diameter can be made as small as possible. Next, the non-contact sensor 50 is moved in the direction of the slit S from the position of the other side of the slit S, and when the reflected light similarly changes, the other edge s2.
Is detected. When this edge s2 is detected, it stops at a position inward of the true edge position s2 by an error δ2.

These errors δ1 and δ2 are equal to each other in the direction symmetrical to the center position of the slit S (inside the edge), and the errors δ1 and δ2 cancel each other with respect to the true edge positions s1 and s2. It will fit. That is,
The non-contact sensor 50 moves from the inner side to the outer side with respect to any of the edges, and both edges s1 and
Since the configuration is such that s2 is detected, the errors δ1, δ2
Even if occurs, it can be generated symmetrically with respect to the center position.

Therefore, even if these errors δ1 and δ2 are present, the intermediate value with respect to the stop position of the head 21 can be directly set to the center position of the slit S. The same calculation process is performed by the arithmetic unit, for example, according to the following expression 1. A value obtained by subtracting s1 from the edge position s2 on the X coordinate of the linear scale graduated in advance (each edge position s1 and s2 is a value including errors δ1 and δ2, respectively)
The center position A can be easily obtained only by performing a calculation process of adding a value obtained by dividing the value of 2 to the value of the edge position s1.

[0066]

(Equation 1)

As another example, the edge position s1 detected on the same X coordinate is stored as a reference value 0, and a value obtained by dividing the value of the edge position s2 with respect to this reference into two is set as the value of the edge position s1. The center position A can be similarly obtained by performing additional calculation processing. The center position A of the slit S calculated in this manner is stored as a reference position when the vertical plane probe 26 described below is inserted into the slit S.

On the other hand, when the slit S is detected, the non-contact sensor 5
When 0 is located inside the slit S, as shown in FIG.
As shown in the schematic diagram of FIG.
Is moved from the inside of the slit S toward the edge.
When the non-contact sensor 50 moves in the edge direction from the position corresponding to the inside of the slit S, the light receiving unit detects one edge s1 by the change of the reflected light, but the true edge position s1.
The head 21 is stopped at the outer position by the error δ1, and the head 21 is positioned at the X coordinate including the error δ1. Similarly, the non-contact sensor 50 is moved in the direction of the edge s2 from the position of the other edge, and when detecting the other edge s2, the non-contact sensor 50 stops at a position outside the true edge position s2 by an error δ2.

Also here, the error δ of the stop position of the head 21
1 and δ2 are generated in a direction symmetrical to the center position of the slit S (outside of the edge), and the errors δ1 and δ2 cancel each other with respect to the true edge positions s1 and s2. Even if there are errors δ1 and δ2, the arithmetic unit can simply determine the intermediate position with respect to the stop position of the head 21 as the center position of the slit S.

In the above description, both edges s of the slit S are
Although the reflected light changes from ON to OFF at 1 and s2, the detection logic of the non-contact sensor 50 may be reversed to change from OFF to ON. Even in this case, the positions where the errors δ1 and δ2 occur are generated at symmetrical positions with respect to the center position, and an error that cancels each other is obtained, so that an accurate center position can be obtained. Further, the movement start position of the non-contact sensor 50 at the time of detecting each edge does not require positioning accuracy, and may be a rough position, which does not affect the edge detection accuracy and also moves to a position from. Just move it in position.

In each case, the object W to be measured is fixed and the non-contact sensor 50 side moves in the X-axis direction, but the slit S of the object W to be measured is Y relative to the bed 2A.
When the axial direction is the width direction and the X-axis direction is the longitudinal direction, the head 21 and the non-contact sensor 5 are arranged.
By fixing 0 and moving the Y-axis table 9 side in the Y-axis direction, the center position of the slit S can be similarly easily obtained.

After the center position A is obtained, the coordinate measuring apparatus 1 is driven by the motors 10 and 17 to move Y.
The axis table 9 and the X-axis table 16 are moved to position the vertical surface probe 26 at the center position above the slit S of the mold W (point A in FIG. 9A). The non-contact sensor 50 and the vertical probe 26 are separated from each other by an interval P1 (see FIG. 4) in the X-axis direction, but the vertical probe 26 can be moved by simply shifting or adding / subtracting the X coordinate corresponding to this interval P1. It can be inserted from the central position A.

After that, the head 21 is manually operated or the motor 22 is operated.
The contact 30 of the vertical surface probe 26 is inserted into the slit S by driving the device in the downward (−Z) direction (point B in FIG. 9A). At this time, the height position of the contact 30 is set approximately in the middle of the vertical surfaces WV facing each other, which are slightly below the horizontal surface WH of the mold W.

Next, the contact 30 of the vertical plane probe 26.
The X-axis table 16 is moved in the + X direction so as to come into contact with one vertical surface WVa of the mold W. Next, the direction of the contact surface 29 of the contact 30 of the vertical surface probe 26 and the measurement interval width (measurement pitch) by the probe 26.
Set. This setting is performed by an input means such as a keyboard.

Next, the X-axis table 16 moves and the contact 30 of the vertical surface probe 26 is moved to the vertical surface WVa of the mold W.
The feeler 27 is moved in the X-axis direction to a position where the feeler 27 is substantially vertical and is substantially straight to the probe main body 28, and the feeler 27 is stopped at a position where the range display indicates substantially 0 (C in FIG. 9A). point).

At this time, the feeler 27 is in a state of being pressed and urged in the direction of the vertical surface WV about the axially supporting portion of the base portion 27a. Further, the three-dimensional coordinate value of the stopped position (point C) at this time is measured, and the displacement value of the probe 26 is corrected to zero.

Next, with the contact 30 in contact with the vertical surface WV of the mold W, the head 21 descends (-Z direction), and the displacement value of the contact 30 greatly changes (see FIG. 9 (a)). )
The middle D point) is set as the measurement start point, and the three-dimensional coordinate value at this position is measured. The point where this displacement value changes greatly is the lowermost end of the vertical surface WV.

Next, the Y-axis table 9 and the X-axis table 1
Only the head 21 is moved upward without moving 6 and the vertical plane probe 26 is moved in a vertical straight line at every set pitch to perform measurement. The measured values are the three-dimensional coordinate value for each pitch and the amount of displacement in the X-axis direction with respect to the Z-axis, and this amount of displacement is the stop position (C
The value is the value of the linearity on the straight line perpendicular to the vertical surface WV with respect to the point), and the measurement is performed. Then, the vertical plane probe 26
Contactor 30 of the vertical plane WV is crossed over the upper edge of the feeler 2
The measurement ends at the point where 7 is changed from the substantially vertical state to the inclined state (point E in FIG. 9A).

The measured values are shown as numerical values and figures in FIG.
As shown in (b), it is displayed on the display and these measurement results are stored.

After the measurement, the head 21 moves upward,
The vertical surface probe 26 is lifted from the mold W (FIG. 9).
(A) Medium F point).

Next, the vertical plane probe 26 located above the horizontal plane WH of the mold W (point F in FIG. 10A) is
1 by a rotary drive mechanism (not shown) provided at the base end
Rotate horizontally by 80 ° and rotate the contact surface 29 of the contact 30 in the opposite direction,
That is, in the present embodiment, it faces in the -X direction. At this time, since the feeler 27 of the probe 26 is inclined with respect to the main body 28, the contact 30 is moved to point G in the figure by this rotation.

Next, the head 21 descends again, and the contact 30 of the probe 26 is moved to the vertical surface W facing the slit S.
At approximately the middle of V, the mold W is inserted into the slit S at a position slightly below the horizontal plane WH and stopped (point H in FIG. 10A).

Next, the contact 30 of the vertical plane probe 26.
The X-axis table 16 is moved in the -X direction so as to be in contact with the other vertical surface WVb of the mold W facing the one vertical surface WVa.

Next, the X-axis table 16 moves, the contact 30 of the vertical surface probe 26 is brought into contact with the other vertical surface WVb of the mold W, and the feeler 27 becomes substantially vertical, so that the probe main body 28. To the position where it becomes almost straight -X
Direction and stop at the position where the range display indicates substantially 0 (point I in FIG. 10A).

At this time, the feeler 27 is in a state of being pressed and biased in the direction of the vertical surface WVb about the axially supporting portion of the base. At this time, the stopped position (I
3D coordinate value of the point) and the probe 26
The displacement value of is corrected to 0.

Next, the contact 30 is the vertical surface WVb of the mold W.
Head 21 descends in contact with
The point where the displacement value due to 7 changes significantly (J in Fig. 10 (a))
Point) is set as the measurement start point, and the three-dimensional coordinate value at this position is measured. The point where this displacement value changes greatly is the lowermost end of the vertical surface WVb.

Next, the Y-axis table 9 and the X-axis table 1
Only the head 21 is moved upward without moving 6 and the vertical plane probe 26 is moved in a vertical straight line at every set pitch to perform measurement.

The measured value is the amount of displacement in the X-axis direction with respect to the three-dimensional coordinate axis and the Z-axis for each pitch, and this amount of displacement is the mold W for the stop position (point I) corrected to zero.
Is the value of the linearity on the vertical straight line of the vertical surface WVb of
Measurement is performed. Then, the contact 30 of the vertical surface probe 26 crosses over the upper edge of the vertical surface WV, and the feeler 27 changes from the substantially vertical state to the inclined state (point K in FIG. 10A).
The measurement ends with.

The measured values are shown as numerical values and figures in FIG.
The display is displayed as shown in 0 (b), and these measurement results are stored.

After the measurement, the head 21 moves upward,
The vertical surface probe 26 is lifted from the mold W (FIG. 10).
(A) L point in the middle).

(B) Measurement of horizontal straightness on the vertical surface WV (see FIG. 11) Next, the Y-axis table 9 and the X-axis table 16 are moved by manual operation or automatic drive (by the motors 10 and 17). Then, the vertical surface probe 26 is positioned above the slit S of the mold W. This moving position is determined by the non-contact sensor 50.
It is the center position A obtained in. Next, the head 21 is moved in the downward (-Z) direction manually or by driving with the motor 22, and the contact 30 of the vertical surface probe 26 is inserted into the slit S at a desired measurement depth (Fig. 11 ( a) Medium B point).
The orientation of the contact surface 29 of the contact 30 is in the initial state when the vertical straightness of the vertical surface WV is measured, that is, on one vertical surface WVa side of the slit S (+ X).
Direction) is set.

Next, the direction of the contact surface 29 of the contact 30 of the vertical surface probe 26, the measurement distance by the probe 26, the moving direction of the probe, and the measurement pitch width are set. This setting is performed by an input means such as a keyboard. In the case of this embodiment, the moving direction of the probe 26 is the −Y direction with respect to the bed 2A.

Next, the X-axis table 16 is moved to bring the contact 30 of the vertical surface probe 26 into contact with the vertical surface WV of the mold W, and the feeler 27 becomes substantially vertical and the probe main body 28 becomes substantially vertical. It is moved to the straight position in the + X direction, stopped at the position where the range display indicates substantially 0, and this point is set as the starting point (point C in FIG. 11A).

At this time, the feeler 27 is pressed and biased in the direction of the vertical surface WV about the pivotal support portion of the base portion 27a. Further, the three-dimensional coordinate value of the stopped position (point C) at this time is measured, and the displacement value of the probe 26 is corrected to zero.

Next, with the contact 30 in contact with the vertical surface WV of the mold W, the head 21 and the X-axis table 16 are not moved, and only the Y-axis table 9 is moved. Then, the vertical surface probe 26 is moved in parallel in a straight line in the -Y direction to perform measurement.

The measured values are the three-dimensional coordinate value for each pitch and the amount of displacement in the X-axis direction with respect to the Y-axis. This amount of displacement is perpendicular to the starting point (point C) corrected to 0 The value is taken as the linearity value on the horizontal straight line of the surface WV, and the measurement is performed. Then, when the contact 30 of the vertical surface probe 26 reaches the set measurement distance (point D in FIG. 11B).
Then, the measurement is completed.

The measured values are shown as numerical values and figures in FIG.
Displayed as shown in FIG. 1 (c), and these measurement results are stored.

After the measurement, the X-axis table 16 is moved in the -X direction to move the vertical surface probe 26 to the vertical surface W of the mold W.
The head 21 is separated from V (point E in FIG. 11B), and the head 21 is moved upward so as to be lifted from within the slit S.

(4) Correction of each measured value Next, the measured value of each linearity obtained by the procedure of (2), (3) (a), (3) and (b) described above, ) Is corrected by the correction value obtained by the procedure
Each straightness on each surface of the actual mold W is calculated by removing the error of the fixed state of the mold W fixed with respect to A.

Then, the shape or numerical value is displayed on the display screen, and the measurement result of the three-dimensional shape is obtained.

Therefore, in the three-dimensional measuring method and apparatus 1 thus constructed, the probe 26 is used when measuring the shape of the mold W as the object to be measured in which the slit S which is a minute gap is formed. , 31 on which the heads 31 are arranged,
Each of the X-axis table 16 provided with the head 21 and the Y-axis table 9 provided with the X-axis table 16 is the bed 2
Since the probes 26 and 31 are linearly moved in a one-dimensional manner when the measurement is performed by the probes 26 and 31 such that the probes 26 and 31 are individually moved linearly with respect to A, the probes 26 and 31 are measured. Since the measurement can be performed while the accuracy of the probes 26 and 31 is maintained without being affected by other than the one driving portion that moves the probe, accurate results can be obtained.

Further, since the respective driving parts are not driven at the same time, the adjustment at the time of manufacturing and assembling or the maintenance can be adjusted so as to maintain accuracy in each part, so that the work is simplified and the structure is simple. Therefore, the entire device can be manufactured at low cost.

Further, unlike the conventional measuring method, since an arbitrary straight line on the surface (WH, WV) to be measured is continuously measured, no error occurs during probe movement, and the reference measurement target object is not generated. Since the horizontality of the horizontal plane WH is measured and corrected to calculate the shape of the measured object W, it is possible to obtain a more reliable measurement result.

Further, the feeler 2 of the vertical plane probe 26
The shape of the tip portion 30 of 7 is a surface 29 that contacts as compared with the conventional case.
Since only the convex spherical surface is used and the measuring method is such that a large impact is not applied at the time of contact, it is possible to make the shape small, so that the slit S of the die W for extrusion molding, which is a minute gap, can be formed. It is possible to sufficiently deal with this, and thereby, it becomes possible to measure the surface shape in the slit S,
Moreover, since the measurement is performed by contact, the reliability of the measured value is improved.

In the above-described embodiment, the fixed state of the mold W as the object to be measured on the Y-axis table 9 is such that the longitudinal direction of the slit S is the Y-axis direction and the width direction is the X-axis direction. Although the measurement procedure of each surface of the slit S in the state is described, the longitudinal direction and the width direction of the slit S are not limited to this state, and when the longitudinal direction is the X axis direction and the width direction is the Y axis direction, In the horizontal and vertical measurement procedure,
The movement directions of the Y-axis table 9 and the X-axis table 16 are changed according to the slit S.

When the object to be measured such as the mold W is obtained in a more strict three-dimensional shape, it can be obtained by performing the above-mentioned procedure in all directions.

Further, although the non-contact sensor 50 described in the above embodiment has been described as having a structure for detecting the edge position and the center position of the concave portion such as the slit S, the non-contact sensor 50 has other convex portions. It may be configured to measure. For example, as shown in the schematic diagrams of FIGS. 14A and 14B, the edge and the center position of the convex portion Wp of the measured object W can be similarly detected. That is, as shown in FIG. 7A, the non-contact sensor 50 is moved from the outer side to the inner side of the convex portion Wp on both sides of the convex portion Wp, or as shown in FIG. By moving the non-contact sensor 50 from the inner side to the outer side with respect to the portion Wp, even if an error occurs in any of them, the occurrence position is a symmetrical position with respect to the center position, so that the center position can be accurately obtained. Like

The center position detecting device provided with the non-contact sensor 50 is not limited to being applied to the three-dimensional measuring device 1,
It is possible to independently detect the center positions of the slits and the convex portions and to obtain the moving position of the processing jig incorporated in another processing device or the like.

[0109]

As described above, according to the center position detecting method and the apparatus therefor according to the present invention, the concave portion such as the slit of the object to be measured is moved so that the non-contact sensor crosses the concave portion, and both edges are moved. Detect the position. Both edge positions are
Since the error is detected from the outer position of the recess toward the inner position, any error will appear symmetrically with respect to the center position of the recess, and the errors will cancel each other out. The center position of the slit can be accurately obtained only by calculating the intermediate value of the included values, and the center position of the slit can be detected with high accuracy with a simple configuration. The non-contact sensor is configured to detect from the inner position of the concave portion of the object to be measured toward the outer position, and also when detecting the convex portion, similarly highly accurate detection of the center position can be performed. .

When the concave portion of the object to be measured is a minute slit, the center position of this slit can be accurately obtained. Therefore, when measuring the state of this slit surface with a contact probe, Since the insertion position of the contact probe with respect to can be made precise, damage to the contact probe or the like can be prevented.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view showing an embodiment of a device to which a center position detecting device of the present invention is applied.

FIG. 2 is a side sectional view of the Y-axis table according to the same embodiment.

FIG. 3 is a front view of an X-axis table and a head according to the same embodiment.

FIG. 4 is a front view of a vertical plane probe, a horizontal plane probe, and a non-contact sensor according to the same embodiment.

5A is a side view showing the tip shape of the vertical plane probe according to the embodiment, and FIG.

FIG. 6A is a schematic perspective view of an object to be measured (mold) measured by the apparatus of the present invention. FIG.

FIG. 7 (a) is a schematic side sectional view showing the procedure for measuring the horizontalness of the horizontal plane of the object to be measured by the device of the present invention.

FIG. 8 (a) is a schematic side sectional view showing the procedure for measuring the linearity of the horizontal plane of the object to be measured by the same device.

FIG. 9 (a) is a schematic side sectional view showing a measuring procedure of vertical straightness of a vertical surface in a slit of an object to be measured by the same device.

FIG. 10 (a) is a schematic side sectional view showing the procedure for measuring the linearity in the vertical direction of the vertical surface in the slit of the object to be measured by the same device.

FIG. 11 (a) is a schematic side sectional view showing a procedure for measuring the horizontal straightness of a vertical surface in a slit of an object to be measured by the same device, (b) the same plan view, and (c) the same display screen.

FIG. 12 is a schematic diagram showing an operation example of detecting the center position of a slit by the center position detecting device of the present invention.

FIG. 13 is a schematic view showing another operation example of detecting the center position of a slit by the center position detecting device of the present invention.

FIG. 14A is a schematic view showing an example of the operation of detecting the central position of a convex portion by the central position detecting device of the present invention. FIG. 14B is another operation of detecting the central position of the convex portion by the central position detecting device of the present invention. Schematic diagram showing an example

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Three-dimensional measuring device 2 ... Base 2A ... Bed 9 ... Y-axis table 16 ... X-axis table 21 ... Head 21a ... Bottom part 26 ... Vertical surface probe 31 ... Horizontal surface probe 50 ... Non-contact sensor (edge measuring means) W ... Object to be measured (mold) Wp ... Convex portion S ... Slit (concave portion) s1, s2 ... Edge (edge position)

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Toshihiko Iwakiri 1-9-3 Kamatahonmachi, Ota-ku, Tokyo Incorporated Niigata Iron Works Engineering Center

Claims (5)

[Claims] 1. A center position detecting method for determining a center position between both edges of a concave portion such as a slit formed in an object to be measured, wherein an edge measurement is performed from an outer position of one edge of the concave portion of the object to an inner part of the concave portion. After moving the means to detect the one edge position, after moving the edge measuring means from the outside position of the other edge of the recess of the object to be measured to the inside of the recess to detect the other edge position, A center position detecting method, characterized in that an intermediate value of the values of one and the other edge positions is obtained as the center position of the recess. 2. A center position detecting method for obtaining a center position between both edges of a concave portion such as a slit formed in an object to be measured, wherein an edge measuring means is provided from an inside position of the concave portion of the object to be measured to an outside direction of one edge. After moving the edge position to detect the one edge position, the edge measuring means is moved from the inside position of the concave portion of the object to be measured to the outside direction of the other edge, and the other edge position is detected. A center position detecting method, wherein an intermediate value of the edge position values is obtained as the center position of the recess. 3. The object to be measured is formed with a convex portion instead of the concave portion, and the edge measuring means detects both edge positions of the convex portion, and determines an intermediate value of the values of both edge positions of the convex portion. The center position detecting method according to claim 1 or 2, wherein the center position is obtained as a center position. 4. A bed on a base on which an object to be measured having a concave portion or a convex portion is placed, and the concave portion or the convex portion of the object to be measured, which is movable in the horizontal direction with respect to the bed. A non-contact sensor that detects both edge positions of the center position, and a calculation unit that determines an intermediate value of the values of the both edge positions detected by the non-contact sensor as the center position of the concave or convex portion. Detection device. 5. The non-contact sensor is provided on a head that is movable in the horizontal direction and the vertical direction with respect to the bed, and the head is in contact with both edge surfaces of the concave portion and is in a state of the edge surface. 5. The center position detecting device according to claim 4, further comprising a contact probe for measuring the position of the contact probe, the contact probe being inserted into the recess from the center position determined by the calculation unit.