JP3527882B2 - Shape measuring device and shape measuring method - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shape measuring device and a shape measuring method for measuring the shape of an arts and crafts in a non-contact manner in detail.

[0002]

2. Description of the Related Art A shape measuring apparatus for measuring the shape of an object to be measured in a non-contact manner, for example, as described in JP-A-61-131859, places the object to be measured at the center of a rotary table.
A non-contact sensor installed so as to face the center of the rotary table is vertically scanned along the rotation axis of the rotary table to measure the outer shape of the measured object. A laser distance sensor is generally used as the non-contact sensor.

FIG. 11 is a state diagram for measuring the outer shape of an object to be measured with a conventional shape measuring apparatus. As shown in FIG. 11A, the measurement light path 211 from the sensor is attached to the handle 20.
The object to be measured 1 is fired and measured every time the object to be measured 1 is rotated by a predetermined angle in the direction of the arrow toward the rotation center C1 of the object to be measured 1, 202, as shown in FIG. 11 (b). Between measurement ray paths 2111 to 2112 and 2113
From 2 to 2114, the outside of the handles 201 and 202 can be measured, but the inside cannot be measured (the portion indicated by the dotted line in the drawing). Here, the measurement light ray paths 2111 to 211
Reference numeral 2114 is a relative display of the measurement light beam path emitted for each rotation of the DUT 1.

FIG. 12 is a state diagram in which the outer shape of another object to be measured is measured by the conventional shape measuring apparatus. As in the case of FIG. 11, there is a portion where the measurement cannot be performed (the dotted line portion in the figure).

[0005]

However, even with the above-described conventional shape measuring device, if the object to be measured is placed at a position deviated from the center of the rotary table, the shape of the protruding portion such as the handle can also be measured. However, there is a problem in that it takes a lot of time and effort to measure the moving dimension and the like when the position of the object to be measured is shifted, and it cannot be easily measured.

It is an object of the present invention to provide a shape measuring apparatus and a shape measuring method capable of easily and faithfully measuring the outer shape of an object to be measured having a protruding portion such as a handle.

To achieve the above object, the shape measuring apparatus of the present invention is characterized in that a rotary table portion on which an object to be measured is placed is attached to an object to be measured with respect to an external sensor. Is configured so that the rotation center of the measurement object can be moved in parallel, and the measurement control device measures the outer shape of the measurement object each time the rotation center of the measurement object is changed with respect to the external sensor, and And a combining unit that combines the measured values.

Specifically, the present invention provides the following apparatus and method.

According to the present invention, a rotatable rotary table part on which an object to be measured is placed, a rotary table drive mechanism for driving the rotary table part, a measurement beam is emitted to the object to be measured, and the object to be measured is An external sensor that receives the measurement beam reflected from the object to be measured, a sensor drive mechanism that supports the external sensor so as to be movable in the height direction of the object to be measured, and based on a signal of the received measurement beam, In a shape measuring device having a rotary table drive mechanism and a measurement control device that drives the sensor drive mechanism to measure the outer shape of the measured object, the rotary table section is configured to measure the external object with respect to the external sensor. The measurement control device measures the outer shape of the measured object each time the rotational center of the measured object is changed with respect to the external sensor. A measuring unit to provide a shape measurement apparatus; and a combining unit for combining the measured values the measurement.

Further, according to the present invention, a rotatable rotary table part on which an object to be measured is placed, a rotary table drive mechanism for driving the rotary table part, a measurement beam is emitted to the object to be measured, An external sensor that receives the measurement beam reflected from the object to be measured, a sensor driving mechanism that movably supports the external sensor in the height direction of the object to be measured, and a signal of the received measurement beam A shape measuring device having a rotary table driving mechanism and a measurement control device that drives the sensor driving mechanism to measure the outer shape of the object to be measured, wherein the external sensor is located at a center of rotation of the facing rotary table portion. It is configured such that the direction of the measurement beam can be translated to the outside, and the measurement control device translates the direction of the measurement beam in parallel to the rotation center of the measured object. Wherein providing a measuring unit for measuring the external shape of the measured object, a shape measuring apparatus, characterized in that it comprises a combining unit for combining the measured values the measured.

Further, according to the present invention, an external sensor emits a measurement beam to an object to be measured placed on a rotary table, and the external sensor receives the measurement beam reflected from the object to be measured. In the shape measuring method for measuring the outer shape of the measured object based on the received measurement beam signal, the first measurement is performed by measuring the outer shape of the measured object at the first rotation center of the rotary table section. Record it as a value,
Next, the outer shape portion of the measured object that cannot be measured in the first measurement is moved either in parallel with the rotation center of the rotary table portion or the external sensor, or the rotary table is rotated. Record the measured value after moving parallel to the outside of the rotation center of the part,
There is provided a shape measuring method characterized by synthesizing each measured value recorded on the basis of the moved size of the parallel movement to measure the outer shape of the measured object.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION A shape measuring apparatus and a shape measuring method according to an embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows the overall configuration of a shape measuring apparatus according to an embodiment of the present invention.

The shape measuring device comprises a workpiece 1 with a handle 2.
And a rotary table section 32 for mounting the
A rotary table drive mechanism 31 for rotating and driving an external sensor 21, an external sensor 21 for measuring an external shape of the DUT 1, and a DUT 1
An internal sensor 22 for measuring the internal shape of the object, a bottom sensor 23 for measuring the distance to the bottom of the DUT 1, an external sensor 21, a sensor drive mechanism 33 for moving the internal sensor 22 and the bottom sensor 23, and an external sensor 21. , The measurement control device 41 for controlling the rotary table drive mechanism 31 and the sensor drive mechanism 33 based on the signals from the internal sensor 22 and the bottom sensor 23, and the rotary table drive mechanism 31 and the sensor drive mechanism 33 are fixedly held. Base 30 and measurement control device 41
And an input / output device 42 which is connected to the device and serves as a man-machine interface.

Optical distance sensors (for example, a semiconductor laser on the light emitting side and a CCD on the light receiving side) are generally used for the external sensor 21, the internal sensor 22, and the bottom sensor 23.

The external sensor 21 is supported by a support arm 37 attached to the horizontal arm 34, emits a measurement beam toward the center of rotation of the rotary table 32 including the object to be measured 1, and reflects from the object 1 to be measured. The received measurement beam is received.

The internal sensor 22 is supported by a support arm 36 attached to a horizontal arm 34, and the measurement beam is reflected by the mirror 2.
Light is emitted and received via 4 to measure the internal shape of the DUT 1. The reason for passing through the mirror 24 is to deal with the DUT 1 having a small inner diameter such that the internal sensor 22 cannot be inserted.

The bottom sensor 23 is supported by the tip of the support arm 36, emits and receives a measurement beam, measures the distance to the bottom of the DUT 1, and detects the downward measurement limit of the internal sensor 22. .

Reference numerals 211, 221, 222, and 231 denote measuring ray paths emitted from the external sensor 21, the internal sensor 22, and the bottom sensor 23.

In order to change the rotational position of the DUT 1, in the case of the rotary table portion 32, the rotation center is changed with respect to the external sensor 21. C1 is the rotation center of the rotary table portion 32, and Cn is the rotation center of the rotary table portion 32 when the predetermined size Tn is shifted.

2 and 3 show details of the rotary table 32. 2 is a top view of the rotary table 32, and FIG. 3 is a vertical sectional view. The rotary table drive mechanism 31 includes
The lower table 3 is connected to the rotary shaft 327 having a square cross section.
33 and an upper table 321 on which the DUT 1 is placed are mounted. A groove 332 on which the rotary shaft 327 slides is provided on the back surface of the upper table 321, and the upper table 321 can be moved in the radial direction of the arrow by the rack 322 and the pinion 323. By moving the upper table 321, the rotational position of the DUT 1 can be changed.

The pinion 323 has brushes 329 and 331.
And is driven by an upper table drive mechanism 324 which is powered via slip rings 328, 330. The limit switch 325 detects that the upper table 321 is at the moved position, and the limit switch 326 detects that the upper table 321 is at the center position of the lower table 333.

The object to be measured 1 is placed on the upper table 321.
It is also possible to dispose a mounting table on which is mounted, slide the mounting table by a certain size, and change the rotation center of the DUT 1.

The sensor drive mechanism 33 moves the external sensor 21 supported by the support arm 37, and the internal sensor 22 and the bottom sensor 23 supported by the support arm 36 up and down.

FIG. 4 shows the details of the sensor drive mechanism 33. On the base 30, three vertical drive shafts 341, 342,
343 is provided, and the horizontal arm 34 to which the support arms 36 and 37 are attached is rigidly supported. The vertical drive shaft 341 and the vertical drive shaft 343 are connected to the horizontal arm 34 in a sliding structure. The vertical drive shaft 342 and the horizontal arm 34 are
It is coupled with a ball screw and a nut structure, and the vertical drive shaft 342 is rotated by the vertical drive device 344,
The horizontal arm 34 is vertically movable.

Returning to FIG. 1, the rotary table drive mechanism 31.
The sensor driving mechanism 33 operates by receiving a control signal from the measurement control device 41 through the control amplifier 35. The output signals of the external sensor 21, the internal sensor 22, and the bottom sensor 23 are taken into the measurement control device 41 through the input amplifier 25.

The lower limit of the sensor drive mechanism 33 is detected by the bottom detection signal of the bottom sensor 23, and the upper limit of the sensor drive mechanism 33 is measured because the external sensor 21 no longer receives the measurement beam reflected from the DUT 1. The upper limit is detected based on the deviation from the range.

The measurement positions of the internal sensor 22 and the external sensor 21 are vertically displaced because the internal sensor 22 stops before reaching the bottom of the DUT 1 for safety, but at that time, In order to measure the whole from the bottom to the top of the DUT 1 by installing the external sensor 21 below the bottom of the DUT 1 to eliminate measurement leakage of the external shape of the DUT 1. Is.

When the surface of the DUT 1 on the rotary table 32 has an external protrusion such as a pot with a handle, the external sensor 21 facing the center of rotation of the rotary table 32 is affected by the external protrusion. In some cases, the measurement beam emitted toward the DUT 1 is blocked and a shadow is formed, and the shadow cannot be measured.

In this embodiment, when there is a shadow and there is a portion that cannot be measured, as shown in FIG. 5, the center of rotation of the rotary table 32 is changed from C1 in FIG. 5A to C2 in FIG. 5B. Move to. At this time, the measuring light ray path of the external sensor 21 is directed to the rotation center C2, so that the rotation light center of the object to be measured 1 moves in parallel, so that a measuring light ray path such as 2117 or 21111 becomes possible. The front and rear measuring ray paths also enable measurement of the parts that could not be measured. Measurement light beam paths 2116 to 211 shown in FIG.
Reference numeral 12 is a relative display of the measurement light beam paths sequentially emitted to the rotating DUT 1.

FIG. 6 shows a functional configuration of the measurement control device 41 shown in FIG. The measurement control device 41 includes a measurement signal processing unit 411.
A measurement result storage unit 412 and a measurement result combining unit 413.
A measurement omission detection unit 414, a rotary table / sensor drive control unit 415, an end / stop determination unit 416, an output style creation unit 417, and an operation signal processing unit 418.

The measurement signal processing unit 411 calculates the external radius of the object to be measured 1 based on the measurement signal output from the external sensor 21 each time the rotational center of the object to be measured 1 is changed.

The measurement result storage unit 412 stores each calculated measurement value.

The measurement result synthesizing unit 413 synthesizes the stored measurement values.

The measurement omission detection unit 414 detects a portion that cannot be measured during measurement of the outer shape of the DUT 1, for example, a portion shadowed by a protrusion such as a handle, and outputs detection information to the rotary table / sensor drive control unit. Output to 415.

Rotary table / sensor drive controller 415
Drives and controls the rotary table drive mechanism 31 or the sensor drive mechanism 33 in order to measure the outer shape of the DUT 1, and based on the detection information from the measurement missing detection unit 414, the rotation center of the DUT 1. In order to change, the rotation center of the rotary table section 32 is changed and the measurement of the missing portion is added.

The end / stop determination unit 416 is based on the signals from the respective sensors, and the rotary table / sensor drive control unit 41.
An instruction to end / stop the operation of the rotary table drive mechanism 31 or the sensor drive mechanism 33 is output to 5.

The output style creating section 417 creates an output style for outputting the synthesis result synthesized by the measurement result synthesis section 413 to the input / output device 42.

The operation signal processing section 418 is provided in the input / output device 42.
It processes the operation signal from and outputs it to the rotary table / sensor drive control unit 415.

FIG. 7 shows a flowchart of the measurement missing detection operation of the measurement control device 41 of FIG. Step 4111
The measurement signal from the external sensor 21 is taken in, and the external radius R of the DUT 1 is calculated based on the measurement signal taken in next (4112). Next, the calculated external radius R is differentiated with respect to the rotation angle θ to obtain dR / dθ (4121).

Next, the measurement missing portion, for example, the shadow portion,
As shown in FIG. 11, since the measured external radius R changes abruptly, a point having a large differential value dR / dθ of the radius R is searched for and a shadowed portion is determined (4122). Since the differential value can be negative, use the absolute value.

Next, when it is determined in step 4122 that there is a shadow, the Z coordinate of the shadowed part is registered (412).
3).

As for the criterion Δ for the magnitude of the differential value, the smaller the shadow, the finer the shadow can be detected. However, since the false determination due to noise increases, about 10% of the maximum diameter of the DUT 1 is appropriate.

The outer radius R of the object 1 to be measured when the center of rotation of the turntable 32 is not changed can be calculated by the following equation (Equation 1). The rotation angle θ of the turntable portion 32 is measured clockwise.

Ro (θ, z) = Roo−Xo (θ, z) (Equation 1) Ro (θ, z): External shape of the object measured from the rotation center Roo: External sensor 21 measured from the rotation center Radial deviation Xo (θ, z): measured value of external sensor 21 at height z and rotation angle θ

Further, the inner diameter of the object to be measured 1 is calculated by the following equation (Equation 2).
Can be found at.

Ri (θ, z + Δz)) = Xi (θ, z + Δz) (Equation 2) Ri (θ, z + Δz): Inner diameter Xi (θ, z + Δz) of the object measured from the rotation center: Height z, Measurement value Δz of the internal sensor 22 at the rotation angle θ: the internal sensor 22 based on the height of the external sensor
Deviation of height

Note that Xi (θ, z + Δz) is a value obtained by correcting the measurement value of the internal sensor 22 by the distance from the internal sensor 22 to the mirror 24.

Further, the thickness of the body of the DUT 1 can be obtained by the following equation (Equation 3).

T (θ, z) = Ro (θ, z) −Ri (θ, z) (Equation 3) T (θ, z): Body part of the measured object at height z and rotation angle θ Thickness of

FIG. 8 is an explanatory diagram for calculating the outer radius of the DUT 1 when the rotation center of the rotary table section 32 is changed in order to change the rotation center of the DUT 1. The center of rotation of the rotary table 32 is moved from C1 to C3. Sections 201 and 202 of the handle 2 and section 10 of the body of the DUT 1
The relative positional relationship of 1 is the same as when the center of rotation is C1. Since the optical axis of the external sensor 21 faces the rotation center C3, the measuring ray path is as shown in S31. D
1 is a point indicating the position of the DUT 1 on the body surface, and D
4 is a point indicating the position on the surface of the handle 2. SC is a line indicating the moving direction of the rotation center of the turntable 32.

The external radius of the DUT 1 in this case is calculated by the following equation (Equation 4).

Ro (θ, z) = {[(Roo−Ro (θ, z) sin (π / 2−θ)] 2 + [(Roo−Ro (θ, z) cos (π / 2−θ)) -ΔR] 2} 1/2 = {[Roo-Ro (θ, z)] 2-2ΔR [Roo-Ro (θ, z)] x cos (π / 2-θ) + ΔR2} 1/2… (number 4) ΔR: Radial displacement of the measured object based on the rotary table 32.

As described above with reference to FIGS. 7 and 8, according to the present invention, the outer shape of the object to be measured 1 is measured at the rotation center C1 to be 1
The measurement value of the second time is recorded, and the rotation center of the DUT 1 is moved in parallel so that a portion that cannot be measured by the first measurement, for example, a shaded portion can be measured, and the second rotation center C3 is used for the second measurement. By recording the measured value and combining the measured value of the first time and the measured value of the second time on the basis of the moving dimension of the parallel movement, the entire outer shape of the DUT 1 can be measured. is there.

FIG. 9 is a flow chart of the measuring operation of the shape measuring apparatus of FIG. 1, and is an example of the measuring operation when measuring the object 1 to be measured such as a pot having a space inside. In step 500, raise the horizontal arm 34 to the upper limit of movement,
The upper table 321 of the rotary table section 32 is set at the center position (505). Next, place the DUT 1 on the upper table 3
Place it in the center of 21 (510).

Next, the support arm 36 is installed at the center of the inner diameter of the DUT 1, the horizontal arm 34 is lowered and inserted inside (515), and when the bottom sensor 23 operates, step 515 ends (520). ). Next, the rotary table section 3
The horizontal arm 34 is scanned in the upward direction while rotating 2 and the internal and external shapes of the DUT 1 are measured by the external sensor 21 and the internal sensor 22 (520). External sensor 2
It is detected that 1 has passed the upper end of the object to be measured, and the measurement is ended (530).

Next, in order to change the center of rotation of the DUT 1, when changing the center of rotation of the rotary table section 32 (5
35), the support arm 36 is swung upward, and the support arm 36 is placed at a position where it does not contact the DUT 1 when the horizontal arm 34 is lowered (540). Next, the upper table 321
Is moved in the radial direction until the limit switch 325 operates, and the rotation center of the rotary table section 32 is changed (5
45). Next, at the time of measurement in step 525, a portion that is shaded and cannot be measured is measured (550). It is confirmed that the measurement of the required portion is completed, and all the measurements are completed (555).

In the flowchart of FIG. 9, when there is no space inside the DUT 1, in the above steps,
Steps 500, 515 and 540 are unnecessary.

In the embodiment of FIG. 1, the center of rotation of the rotary table 32 is changed in order to change the center of rotation of the DUT 1. However, FIG. 10 shows another embodiment of the present invention. As described above, the external sensor 21 is moved in parallel by a predetermined dimension,
Even if the position of the external sensor 21 is changed, the same effect as that of the embodiment of FIG. 1 can be obtained.

The measurement light beam path 211 is directed to the rotation center C1 in a state where the rotation center of the rotary table section 32 is not changed.
Is translated in 2120. When the DUT 1 is rotated in this state, the measurement light beam path is changed from 2120 to 2120.
121, 2122 and then 2138 in that order to return to the state of 2120.

The inside of the handle 201 is the measurement light path 2
It can be measured in the state of 138. Similarly, the measurement light path 21
At 20 and 2121, the body part which is the shadow of the handle 201 can be measured. The shadowed portion of the handle 202 can be measured with the measuring ray paths 2129, 2131, 2132, or the like. The measurement light ray paths 2120 to 2138 are relative display of the measurement light ray paths sequentially emitted to the rotating DUT 1.

When the handle is attached in the horizontal direction, by tilting the direction of the external sensor 21 from the horizontal direction, the shadowed portion of the handle of the DUT 1 can be measured in the same manner as above.

As still another embodiment of the present invention, the object to be measured 1 is placed on the upper table 321 of the rotary table section 32.
1 may be configured by placing a mounting table on which the table is mounted and sliding the mounting table by a predetermined dimension to change the rotation center of the DUT 1.
It is possible to obtain the same effect as that of the embodiment.

[0063]

According to the present invention, it is possible to easily and faithfully measure the outer shape of an object to be measured having a protruding portion such as a handle, and thus, for example, a complex arts and crafts or archaeological excavated product. It is possible to improve the efficiency of shape measurement work and to contribute to highly accurate measurement.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram of a shape measuring apparatus according to an embodiment of the present invention.

FIG. 2 is a top view of the rotary table section in FIG.

FIG. 3 is a vertical cross-sectional view of the rotary table section in FIG.

FIG. 4 is a detailed view of the sensor driving mechanism of FIG.

FIG. 5 is a diagram showing a direction of a measuring light beam path when a rotation center of a turntable unit is changed.

FIG. 6 is a functional configuration diagram of the measurement control device in FIG. 1.

FIG. 7 is a flowchart of a measurement missing detection operation of the measurement control device of FIG.

FIG. 8 is an explanatory diagram for calculating the external radius of the measured object when the rotation center of the rotary table unit is changed.

9 is a flow chart diagram of a measuring operation of the shape measuring apparatus of FIG.

FIG. 10 is an explanatory diagram for measuring a shadow portion by moving an external sensor in parallel according to another embodiment of the present invention.

FIG. 11 is a state diagram of measuring the outer shape of an object to be measured with a conventional shape measuring device.

FIG. 12 is a state diagram of measuring the outer shape of another measured object with a conventional shape measuring apparatus.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Object to be measured, 2 ... Handle of object to be measured, 21 ... External sensor, 22 ... Internal sensor, 23 ... Bottom sensor, 31 ... Rotating table drive mechanism, 32 ... Rotating table part, 33 ... Sensor drive mechanism, 41 ... Measurement control device, 42 ... Input / output device,
411 ... Measurement signal processing unit, 412 ... Measurement result storage unit, 4
13 ... Measurement result synthesizing unit, 414 ... Measurement missing detecting unit, 41
5 ... rotary table / sensor drive control unit, 416 ... end /
Stop determination unit, 417 ... Output style creation unit, 418 ... Operation signal processing unit

Continuation of the front page (56) Reference JP-A-7-181022 (JP, A) JP-A-6-18232 (JP, A) JP-A-2000-241133 (JP, A) JP-A-61-131659 (JP, A) JP 53-146656 (JP, A) JP 11-230721 (JP, A) JP 5-126541 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) ) G01B 11/24

Claims (3)

(57) [Claims] 1. A rotatable rotary table section on which an object to be measured is placed, a rotary table drive mechanism for driving the rotary table section, a measurement beam is emitted to the object to be measured, and the object to be measured is provided. An external sensor that receives the measurement beam reflected from the sensor, a sensor drive mechanism that movably supports the external sensor in the height direction of the object to be measured, and the rotary table based on a signal of the received measurement beam. In a shape measuring device having a drive mechanism and a measurement control device that drives the sensor driving mechanism to measure the outer shape of the measured object, the rotary table section is a rotation center of the measured object with respect to the external sensor. Is configured to be movable in parallel, and the measurement control device measures the outer shape of the measured object each time the rotation center of the measured object is changed with respect to the external sensor. The shape measuring apparatus characterized by having a combining unit for combining the measured values the measurement. 2. A rotatable rotary table section on which an object to be measured is placed, a rotary table drive mechanism for driving the rotary table section, a measurement beam is emitted to the object to be measured, and the object to be measured is provided. An external sensor that receives the measurement beam reflected from the sensor, a sensor drive mechanism that movably supports the external sensor in the height direction of the object to be measured, and the rotary table based on a signal of the received measurement beam. In a shape measurement device having a drive mechanism and a measurement control device that drives the sensor drive mechanism to measure the outer shape of the object to be measured, the external sensor measures the outside of a rotation center of the facing rotary table section. The measurement control device is configured so that the direction of the beam can be moved in parallel, and the measurement control device is configured to move the direction of the measurement beam in parallel with respect to the rotation center of the measurement target. A measuring unit for measuring the outer shape of the shape measuring apparatus characterized by having a combining unit for combining the measured values the measurement. 3. A measurement beam emitted from an external sensor to an object to be measured placed on a rotary table part, the measurement beam reflected from the object to be measured is received by the external sensor, and the received measurement beam is received. In the shape measuring method of measuring the outer shape of the measured object based on the signal of, the outer shape of the measured object is measured at the first rotation center of the rotary table section and recorded as a first measurement value. Next, with respect to the outer shape portion of the measured object that cannot be measured in the first measurement, either one of the rotary table portion or the external sensor is moved in parallel with respect to the external sensor, or the rotation center is rotated. The measurement value measured after the parallel movement to the outside of the rotation center of the table part is recorded, and the respective measurement values recorded based on the parallel movement size are combined to obtain the outer shape of the measured object. A shape measuring method characterized by measuring