JP5310336B2 - measuring device - Google Patents

Description

  The present invention relates to a measuring apparatus, and more particularly, to a measuring apparatus that can measure a test object with high accuracy.

  In general, in a measuring instrument that measures the shape of a test object in two dimensions or three dimensions, measurement from an arbitrary direction can be performed by rotating or tilting the posture of the test object. In such a measuring machine, in order to rotate or tilt the test object, a rotating table having a single rotating shaft and an inclined rotating table having two rotating shafts and an inclined shaft are provided.

  For example, Patent Literature 1 discloses an inclined rotary table that includes a rotary table that rotates a table surface on which a test object is placed, and a support base that tilts the rotary table.

JP 2005-138275 A

  However, in a measuring apparatus equipped with an inclined rotation table, minute displacements (such as displacement and blurring) may occur in the support portion that supports the inclination axis or the rotation axis due to the weight of the test object or the deviation of the center of gravity. This displacement may cause the position of the test object to deviate from the original position. And since a measurement error generate | occur | produces by such a micro displacement, a measurement precision will fall and it was difficult to measure a test object with high precision.

  The present invention has been made in view of such a situation, and makes it possible to measure a test object with high accuracy.

  The measuring device of the present invention is a measuring device for measuring a three-dimensional shape of a test object, the rotary table on which the test object is mounted and driven to rotate about a predetermined rotation axis, and the rotation A tilt table on which a table is rotatably mounted and driven to tilt around a tilt axis extending in the horizontal direction, first displacement measuring means for measuring a displacement of the rotary table with respect to the tilt table, and a vertical direction of the tilt table And a second displacement measuring means for measuring the displacement of the first and second displacements.

  In the measuring apparatus of the present invention, the test object is placed on a rotary table that is driven to rotate about a predetermined rotary axis, and the rotary table can be rotated by an inclined table that is driven to tilt about an inclined axis extending in the horizontal direction. The displacement of the rotary table relative to the tilt table is measured by the first displacement measuring means, and the vertical displacement of the tilt table is measured by the second displacement measuring means. Thereby, based on the measurement result by the 1st and 2nd displacement measuring means, a measurement result can be corrected so that the displacement of a rotation table and an inclination table may be canceled, and a test object is measured with high accuracy. be able to.

  Further, the second displacement measuring means can be disposed substantially directly below the intersection of the rotation axis of the rotary table and the tilt axis of the tilt table. With such an arrangement, the displacement can be measured effectively with few sensors.

  Further, the rotary shaft of the rotary table can be arranged approximately in the middle between the support portions that support both ends of the tilt table. Further, the first displacement measuring means can be disposed at at least three locations that are substantially equidistant along the circumference centered on the rotation axis of the rotary table. Thereby, it can measure efficiently.

  According to the measuring apparatus of the present invention, a test object can be measured with high accuracy.

It is a figure which shows the structural example of one Embodiment of the measuring apparatus to which this invention is applied. It is a three-view figure of the inclination rotation table of a measuring device. It is a figure explaining the measurement of the to-be-tested object on the rotary table inclined by the predetermined inclination angle. It is a block diagram which shows the structural example of the control apparatus which controls a measuring apparatus.

  Hereinafter, specific embodiments to which the present invention is applied will be described in detail with reference to the drawings.

  FIG. 1 is a diagram showing a configuration example of an embodiment of a measuring apparatus to which the present invention is applied.

  As shown in FIG. 1, the measuring device 11 has a surface plate 13 on which a stone or cast iron surface plate 13 is placed on a gantry 12 that can adjust the level of the measuring device 11 as a whole, and is kept horizontal. An inclined rotary table 14 is placed on the upper surface of 13.

  The surface plate 13 is formed so that the end portion (the right end portion in FIG. 1) also serves as the Y-axis guide of the portal frame 15 that can be driven on the surface plate 13 in the Y-axis direction (depth direction in FIG. 1). Has been. The portal frame 15 includes an X-axis guide 15a extending in the X-axis direction (left-right direction in FIG. 1), a driving side column 15b driven along the Y-axis guide of the surface plate 13, and a surface plate according to driving of the driving side column 15b. 13 is constituted by a driven side column 15c that slides on the upper surface of 13.

  The head portion 16 can be driven along the X-axis guide 15 a of the portal frame 15, and a Z-axis guide 17 that can be driven in the Z-axis direction (vertical direction in FIG. 1) is attached to the head portion 16. Yes. A measurement probe 18 is attached to the lower end of the Z-axis guide 17, and the measurement probe 18 is configured to be rotatable about the Z axis and tiltable about a predetermined axis in the horizontal direction. .

  As described above, in the measurement apparatus 11, the measurement probe 18 can be freely moved in each of the X direction, the Y direction, and the Z direction by driving the portal frame 15, the head unit 16, and the Z axis guide 17. The tip of the measurement probe 18 can be directed in an arbitrary direction by rotating and tilting the measurement probe 18.

  The tilt rotation table 14 is a tilt table on which a test object (for example, a test object 41 in FIG. 3 to be described later) is mounted on the upper surface, and the rotary table 21 is rotatably mounted around the rotation axis L1. The table 22 and support portions 23 and 24 that rotatably support the tilt table 22 about the tilt axis L2 extending in the X-axis direction are configured.

  The tilt table 22 has a built-in rotary shaft drive motor 22a, and the axis that serves as a center for the rotary shaft drive motor 22a to rotationally drive the rotary table 21 is the rotary shaft L1. Moreover, the support part 23 incorporates the inclination axis drive motor 23a, and the inclination axis drive motor 23a rotates the inclination table 22 around the inclination axis L2, thereby making the rotation table 21 predetermined with respect to the horizontal plane. Tilt at a tilt angle of.

  As described above, in the tilt rotary table 14, the test object placed on the rotary table 21 can be held in an arbitrary posture by rotating the rotary table 21 and tilting the tilt table 22. The rotary table 21 is configured so that the test object can be fixed so that the test object does not shift even when the tilt angle of the tilt table 22 becomes steep.

  And in the measuring apparatus 11, the attitude | position of the test object mounted in the rotary table 21 is hold | maintained by the predetermined inclination angle and inclination direction, and the measurement probe 18 is made to contact | abut to a test object from arbitrary directions, The three-dimensional shape of the test object is measured.

  Further, the inclined rotary table 14 is designed so that the table surface of the rotary table 21 (the upper surface of the rotary table 21 on which the test object is placed) is orthogonal to the rotation axis L1. However, since the rotary table 21 is rotatably supported with respect to the tilt table 22 in the tilt rotary table 14, the rotation of the tilt rotary table 14 depends on the weight of the test object placed on the rotary table 21 and the deviation of the center of gravity. The table surface of the rotary table 21 may be slightly displaced with respect to a surface orthogonal to the rotation axis L1 (hereinafter, referred to as “surface vibration” as appropriate) with a support portion (for example, a ball bearing) as a center.

  Further, since the tilt table 22 is rotatably supported with respect to the support portions 23 and 24, the tilt table 22 may be slightly displaced at the rotation support portions at both ends of the tilt table 22, and is placed on the turn table 21. Due to the weight of the test object, the entire tilting table 22 may be displaced downward in the Z direction, which is the vertical direction (hereinafter referred to as “sinking” as appropriate).

  As described above, the surface shake of the rotary table 21 and the sinking of the tilt table 22 occur, so that the position of the test object changes when the rotary table 21 is rotated or the tilt table 22 is tilted (that is, It is conceivable that a deviation from the original position occurs) and a measurement error occurs due to the change in the position.

  Therefore, the measuring apparatus 11 performs surface blurring of the rotary table 21 and sinking of the tilting table 22 in order to correct such a change in the position of the test object (that is, set the change amount to 0). A plurality of sensors (displacement sensors 31 to 34 in FIG. 2) to be measured are provided on the tilt rotation table 14, and correction means (in FIG. 4) corrects the measured values of the test object based on the displacements measured by these sensors. A control device 51 having a position correction unit 58) is provided.

  That is, in the measuring apparatus 11, based on the outputs of a plurality of sensors provided on the tilt rotation table 14, the control apparatus 51 changes the position of the test object due to surface shake of the rotary table 21 and sinking of the tilt table 22. Correction is performed to eliminate the above.

  Next, with reference to FIG. 2, the several sensor provided in the inclination rotation table 14 is demonstrated. FIG. 2 shows a three-side view of the tilt rotation table 14.

  As shown in FIG. 2, the tilt rotary table 14 includes three displacement sensors 31 to 33 for measuring the surface shake of the rotary table 21 and a displacement sensor 34 for measuring the sinking of the tilt table 22. The displacement sensors 31 to 34 output the measurement results to the control device 51. As the displacement sensors 31 to 34, for example, a sensor that generates an eddy current using a high-frequency electromagnetic field and measures an interval (distance) by a change in an oscillation state can be used.

  The displacement sensors 31 to 33 are arranged on the upper surface of the tilting table 22 so as to be equally spaced along a circumference around the rotation axis L <b> 1 that is the rotation center of the rotation table 21. Further, the displacement sensors 31 to 33 are arranged below the rotary table 21 so that the upper end surface, which is a measurement unit, and the lower surface of the rotary table 21 have a predetermined interval, and the distance from the lower surface of the rotary table 21 is. Measure.

  For example, the inclined rotary table 14 is in a state in which the test object is not placed on the rotary table 21 and the rotary table 21 is horizontal, and the upper end surface of each of the displacement sensors 31 to 33. It is designed so that the lower surface of the rotary table 21 has the same distance. When the surface blur of the rotary table 21 occurs as described above by placing the test object, the distance between the upper end surface of each of the displacement sensors 31 to 33 and the lower surface of the rotary table 21 changes, Is measured by the displacement sensors 31 to 33.

  Here, the turntable 21 has sufficiently high rigidity (flatness and rigidity against torsion) so that its own deformation can be ignored, and when the test object is placed on the turntable 21, Surface blurring occurs around a guide 22b (bearing or the like) in the tilt table 22 that rotatably supports the shaft portion of the rotary table 21, and the interval measured by the displacement sensors 31 to 33 changes. Accordingly, one plane defined by the measurement at the three points by the displacement sensors 31 to 33 is regarded as the table surface of the rotary table 21 in a state where the surface blur has occurred, that is, the surface blur that has occurred in the rotary table 21. Can be grasped.

  Further, the displacement sensor 34 is disposed on the upper surface of the base 35 on which the support portions 23 and 24 are arranged on both sides, and is directly below the intersection of the rotation axis L1 of the rotary table 21 and the tilt axis 22 of the tilt table 22. Be placed. For example, when the table surface of the rotary table 21 is horizontal, the displacement sensor 34 is disposed below the rotation axis L1 in the vertical direction.

  Here, in the tilting rotary table 14, the rotation axis L1 of the rotary table 21 is arranged in the middle of the guides 23b and 24b (bearings and the like) in the support portions 23 and 24 that rotatably support the shaft portion of the tilting table 22. Thus, the displacement sensor 34 measures the sinking of the tilting table 22 in the middle. That is, the displacement sensor 34 is arranged so that the distance from the displacement sensor 34 to the guide 23b is equal to the distance from the displacement sensor 34 to the guide 24b.

  Further, as shown in the side view of FIG. 2, the lower surface of the tilt table 22 is a semicircular curved surface with the tilt axis L2 as the center, and the displacement sensor 34 is measured even when the tilt table 22 is tilted. The distance between the upper end surface, which is a portion, and the lower surface of the tilt table 22 is constant.

  When the test object is placed on the rotary table 21 and the sinking of the tilting table 22 occurs, the distance between the upper end surface of the displacement sensor 34 and the lower surface of the tilting table 22 is narrowed. Measured.

  As described above, in the tilt rotary table 14, the surface shake of the rotary table 21 is measured by the displacement sensors 31 to 33, and the sinking of the tilt table 22 is measured by the displacement sensor 34. Then, based on the measurement results of the displacement sensors 31 to 34, as will be described later with reference to FIG. 4, the control device 51 can make corrections so as to eliminate the displacement of the test object, so that high-precision measurement is possible. It can be performed.

  Next, an example in which the test object 41 on the rotary table 21 tilted at a predetermined tilt angle is measured using the measurement probe 18 will be described with reference to FIG.

  For example, after measuring the side face 42 by bringing the measuring probe 18 into contact with the side face 42 of the test object 41 facing to the lower right in FIG. 3, the rotary table 21 is rotated 90 degrees and turned to the front side in FIG. 3. When the side surface 43 of the test object 41 is directed to the lower right and the side surface 43 is measured in the same manner as the side surface 42, the posture of the test object 41 changes as the rotary table 21 rotates. For this reason, when the position of the center of gravity changes in accordance with the deviation of the center of gravity of the test object 41, surface shake of the rotary table 21 occurs, or the tilt table 22 sinks.

  Therefore, in the measuring device 11, every time the turntable 21 is rotated, the measurement by the displacement sensors 31 to 34 is performed. If the measurement values by the displacement sensors 31 to 34 change before and after the rotation of the rotary table 21, the measurement result by the measurement probe 18 is corrected based on the amount of change of the measurement values. That is, the measurement result obtained by the measurement probe 18 is corrected so as to eliminate the surface blurring of the rotary table 21 and the sinking of the tilting table 22, that is, the change amount of the interval generated by the surface blurring and sinking becomes zero. It is corrected.

  Further, when measuring the side surface 44 of the test object 41 facing the upper right in FIG. 3, if the tilt table 22 is tilted, the movement of the center of gravity accompanying the change in the posture of the rotary table 21 causes the surface shake of the rotary table 21. Or the sinking of the tilting table 22 occurs. Therefore, in the measurement apparatus 11, the measurement result by the measurement probe 18 is corrected based on the measurement results of the displacement sensors 31 to 34 every time the tilt table 22 is tilted, similar to when the rotary table 21 is rotated.

  As described above, in the measurement apparatus 11, the measurement result by the measurement probe 18 is corrected based on the measurement results of the displacement sensors 31 to 34, so that the adverse effect due to the surface blur of the rotary table 21 and the sinking of the tilt table 22 is measured. 18 can be avoided from being reflected in the measurement result, and highly accurate measurement with few errors can be performed.

  Moreover, in the measuring apparatus 11, as shown in FIG. 2, since the displacement sensor 34 is arrange | positioned in the perpendicular direction downward of the rotating shaft L1 when the table surface of the turntable 21 is horizontal, the inclination table 22 with a small number of sensors. Can be measured effectively.

  Further, the measuring apparatus 11 is configured such that both ends of the tilt table 22 are supported by the guides 23b and 24b, and the rotation axis L1 is arranged at an intermediate point between the guides 23b and 24b. The displacement of the tilt table 22 when the object 41 is placed is limited only to the lower side in the vertical direction. As a result, the displacement of the tilt table 22 can be measured only by disposing only one displacement sensor 34 at the intermediate point between the guides 23b and 24b.

  Further, since the displacement sensors 31 to 33 are arranged at equal intervals along the circumference around the rotation axis L1 which is the rotation center of the rotation table 21, the surface shake of the rotation table 21 is easy. Can be measured.

  Thus, in the measuring apparatus 11, the displacement sensors 31 to 34 are appropriately arranged, and the surface shake of the rotary table 21 and the sinking of the tilt table 22 can be measured with the minimum number of sensors. Therefore, it is possible to efficiently measure the surface shake of the rotary table 21 and the sinking of the tilt table 22, and to configure the measuring device 11 at a low cost.

  Next, FIG. 4 is a block diagram illustrating a configuration example of a control device that controls the measurement device 11 of FIG.

  In the control device 51 of FIG. 4, the X-axis count unit 52 is connected to an X-axis encoder (not shown) of the head unit 16 of FIG. 1, and the head unit 16 is driven along the X-axis guide 15a. In response to this, the signal output from the X-axis encoder is counted, and a count value indicating the result is supplied to the position determination unit 57. Similarly, the Y-axis counting unit 53 supplies a count value corresponding to the driving of the portal frame 15 in the Y-axis direction to the position determining unit 57, and the Z-axis counting unit 54 is the Z-axis direction of the Z-axis guide 17. The count value corresponding to the drive to is supplied to the position determination unit 57.

  The θ-axis counting unit 55 supplies a count value corresponding to the rotation of the rotary table 21 to the position determining unit 57, and the γ-axis counting unit 56 supplies a count value corresponding to the inclination of the tilt table 22 to the position determining unit 57. To supply.

  The position determination unit 57 detects the test based on the count values supplied from the X-axis count unit 52, the Y-axis count unit 53, the Z-axis count unit 54, the θ-axis count unit 55, and the γ-axis count unit 56, respectively. The position of the tip of the measurement probe 18 that comes into contact with the object 41 is determined. Then, the position determination unit 57 supplies coordinate information indicating the tip position of the measurement probe 18 to the position correction unit 58.

  In addition, measurement results from the displacement sensors 31 to 34 are input to the displacement sensor input unit 59. That is, the displacement sensor input unit 59 receives the measurement value indicating the distance between the displacement sensors 31 to 33 and the lower surface of the rotary table 21 and the measurement value indicating the distance between the displacement sensor 34 and the lower surface of the tilt table 22. Is entered. The displacement sensor input unit 59 supplies these measurement results to the position correction unit 58.

  The position correction unit 58 corrects the coordinate information indicating the tip position of the measurement probe 18 supplied from the position determination unit 57 based on the measurement results by the displacement sensors 31 to 34 supplied from the displacement sensor input unit 59, and A process of recording the corrected measurement result in the measurement result recording unit 60 is performed.

  As described above, in the measurement apparatus 11, each time the rotary table 21 is rotated and the tilt table 22 is tilted, the measurement by the displacement sensors 31 to 34 is performed, and the rotation of the rotary table 21 or the tilt table 22 is measured. When the measurement value changes before and after tilting, the position correction unit 58 performs measurement so as to eliminate the surface shake of the rotary table 21 and the sinking of the tilt table 22 based on the change amount of the measurement value. The coordinate information indicating the tip position of the probe 18 is corrected.

  An operation unit 61 including a keyboard and a mouse supplies an operation signal corresponding to a user operation to the control unit 64, and a display unit 62 including a CRT and an LCD is controlled by the position correction unit 58 according to the control of the control unit 64. Displays output measurement results and various messages.

  For example, the control unit 64 displays a message for confirming whether or not correction is performed when measuring the test object 41 on the display unit 62, and displays an operation signal supplied from the operation unit 61 according to a user operation. Based on this, each part of the control device 51 is controlled. The drive unit 63 drives the rotary shaft drive motor 22a and the inclined shaft drive motor 23a, and drive means for driving each of the portal frame 15, the head unit 16, and the Z-axis guide 17 according to the control of the control unit 64. Then, the tip of the measurement probe 18 is brought into contact with the test object 41, and the three-dimensional shape of the test object 41 is measured.

  As described above, the control device 51 is configured, and when the three-dimensional shape of the test object 41 on the rotary table 21 tilted at a predetermined tilt angle is measured, the position correction unit 58 includes a displacement sensor. Since the measurement result of the test object 41 is corrected based on the measurement results of 31 to 34, the measurement can be performed with high accuracy.

  In addition, as a measuring method of the test object 41 by the measuring apparatus 11, an optical measuring method using a laser probe or an image probe can be employed.

  The embodiment of the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the gist of the present invention.

  DESCRIPTION OF SYMBOLS 11 Measurement apparatus, 12 mounts, 13 surface plate, 14 inclination rotation table, 15 portal frame, 16 head part, 17 Z axis guide, 18 measurement probe, 21 rotation table, 22 inclination table, 22a rotation axis drive motor, 23 and 24 support unit, 23a tilt axis drive motor, 31 to 34 displacement sensor, 35 base, 41 test object, 51 control device, 52 X axis count unit, 53 Y axis count unit, 54 Z axis count unit, 55 θ axis Count unit, 56 γ-axis count unit, 57 Position determination unit, 58 Position correction unit, 59 Displacement sensor input unit, 60 Measurement result recording unit, 61 Operation unit, 62 Display unit, 63 Drive unit, 64 Control unit

Claims (5)

In a measuring device that measures the three-dimensional shape of a test object,
A rotating table on which the test object is mounted and driven to rotate around a predetermined rotation axis;
A tilt table on which the rotary table is rotatably mounted and driven to tilt around a tilt axis extending in the horizontal direction;
First displacement measuring means for measuring the displacement of the rotary table with respect to the tilt table;
And a second displacement measuring means for measuring a vertical displacement of the tilt table. The measuring apparatus according to claim 1, wherein the second displacement measuring unit is disposed substantially directly below the intersection of the rotation axis of the rotary table and the tilt axis of the tilt table. . The measuring apparatus according to claim 1, wherein a rotation shaft of the rotary table is disposed substantially in the middle of support portions that support both ends of the tilt table. The first displacement measuring means is disposed at at least three locations that are substantially equidistant along a circumference centered on a rotation axis of the rotary table. The measuring device described in 1. 5. The correcting device according to claim 1, further comprising a correcting unit that corrects a measured value of the test object based on the displacement measured by the first displacement measuring unit and the second displacement measuring unit. The measuring apparatus in any one.

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