JP2005181023A - Apparatus and method for measuring height difference and inclination angle between planes - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accurately measure a height difference and an inclination angle of another plane with respect to one plane among two arbitrary planes of an object having a plurality of planes with high accuracy and easily in a short time. And a tilt angle measuring apparatus and method.
In a measurement object 1 having a plurality of relatively immovable planes, any one plane is used as a comparison reference plane 6, and any other plane is used as a measurement plane 7. The surface plate fixing part 10 having a surface plate surface 17 serving as an inspection reference and the object 1 to be measured on the surface plate surface 17 of the surface plate fixing part 10 are compared with the reference surface 6. A plurality of lifters 16 that are held in contact with each other and a plurality of measurement points measuring the distance to the measurement surface 7 of the measurement target object 1 in a direction parallel to the perpendicular direction of the surface plate surface 17 of the surface plate fixing unit 10. And a distance sensor 14.
[Selection] Figure 1

Description

  The present invention relates to an apparatus and method for measuring a height difference and an angle between planes, and in a measurement target object having a plurality of relatively stationary planes, any one surface is used as a comparison reference plane, and the measurement target object with respect to the reference plane The present invention relates to a technique for easily measuring the height difference and inclination angle of any other plane in a short time.

  Conventionally, in this type of technology, the height difference and the inclination angle between two planes to be measured are a combination of a laser measuring device and an orthogonal two-axis or three-axis moving table for moving the measuring head of the same device. A three-dimensional measuring device or the like is used.

The measurement method is as follows.
1. The distance from the measurement reference position of the apparatus to the three measurement points on the reference plane set for the measurement object is laterally extended.
2. The distance from the measurement reference position of the apparatus to the three measurement points on the measurement surface of the measurement object is laterally extended.
3. Equations for the respective planes are determined for the reference plane and the measurement plane.
4). An inclination angle and a height difference of the measurement surface with respect to the reference surface are obtained by calculation from the determined equation of each plane.

There exists patent document 1 as a prior art document of this kind of technique.
JP-A-4-297809

  However, in the measurement by the conventional method described above, a subtle difference in the length measurement value caused by the surface roughness of the measurement object directly affects the plane equation as a tilt error. Since this error increases in proportion to the distance between the two planes to be measured, the repeated measurement accuracy of the same object to be measured may not satisfy the required accuracy, particularly in the calculation result of the height difference between the two planes.

  Further, when various products are inspected in the same process using the same apparatus, the time required for the length measuring head of the measuring apparatus to physically move between the six measurement points is required for inspecting one product. This is a major factor in time. If the moving time of the measuring head is increased, the number of inspection devices arranged on the production line is increased, which in turn increases the product cost.

  The present invention solves the above-mentioned problem. Of any two planes of an object having a plurality of planes, the height difference and inclination angle of the other plane with respect to one plane can be accurately and easily performed in a short time. The present invention provides an apparatus and a method for measuring a height difference and a tilt angle between planes to be measured.

In order to solve the above-described problem, the measuring device for height difference and inclination angle between planes according to claim 1 of the present invention provides any one plane in a measurement target object having a plurality of relatively stationary planes. A device for measuring a height difference and an inclination angle of a measurement surface with respect to a comparison reference surface, using the other reference surface as a measurement surface as a comparison reference surface,
A surface plate means having a surface plate as an inspection reference, a measurement object holding means for holding the object to be measured in contact with the surface plate surface of the surface plate means on the comparison reference surface, and a perpendicular direction of the surface plate surface of the surface plate means Measuring means for measuring the distance to the measurement surface of the measurement target object at a plurality of measurement points in a direction parallel to the measurement object.

  With the configuration described above, the object to be measured is positioned in contact with the surface plate surface of the surface plate means on the comparison reference surface, so that the surface plate surface and the comparison reference surface have the same positional relationship with no height difference and inclination angle between each other. Therefore, it is not necessary to measure the comparison reference surface of the measurement target object with respect to the surface plate surface of the surface plate means when measuring the height difference and the inclination angle between the comparison reference surface of the measurement target object and the measurement surface, and the inclination angle. By measuring the height difference and the inclination angle of the measurement surface, the height difference and the inclination angle between the comparison reference surface and the measurement surface of the object to be measured can be obtained.

  When measuring, the distance to the surface of the surface plate means is measured in advance as an initial value of the measuring means. For this reason, the master work (reference device) is pressed against the surface plate surface of the surface plate means by the reference surface and is held by the measurement object holding means, and the reference surface of the master work facing the measurement means is assumed to be equivalent to the surface plate surface. Measure the distance to the surface with the measuring means.

  The standard master work has a single reference plane, but the area where the reference plane is pressed against the surface of the surface plate means (first reference surface) and the area facing the measurement means (second reference surface) ) As different planes, and having a known height difference and inclination angle as correction values between the two regions. In this case, the measured value is corrected with the correction value.

  At the time of this measurement, the object to be measured is brought into contact with the surface plate surface of the surface plate means at the comparison reference surface and held by the object object holding means, and the distance to the surface to be measured of the object to be measured facing the measuring means is measured. The difference between the measured actual value measured and the initial value is taken as the measured value.

  This will be described in detail below. Assuming that a virtual plane parallel to the surface plate is superimposed on the reference surface of the master work and the measurement surface of the object to be measured, set the X axis and Y axis perpendicular to the virtual plane, and set the intersection of the X axis and Y axis. As a reference point, a first measurement point on the Y axis that is separated from the X axis and the Y axis by a predetermined distance, a second measurement point on the intersection of the X axis and the Y axis, and a third measurement on the X axis A point is set, and the distance between the first measurement point and the second measurement point and the distance between the second measurement point and the third measurement point are set to known predetermined values.

  When measuring the initial value, the first measurement point on the Y axis projected onto the reference surface of the master work facing the measurement means, the second measurement point on the intersection of the X axis and the Y axis, and the third measurement point on the X axis. Measure at each measurement point.

The measured values at the respective measurement points are respectively the initial value of the first measurement point on the Y axis, the initial value of the second measurement point on the intersection of the X axis and the Y axis, and the initial value of the third measurement point on the X axis. Value.
At the time of this measurement, the object to be measured is brought into contact with the surface plate surface of the surface plate means at the comparison reference plane and held by the object object holding means, and the object to be measured is opposed to the measuring means at the same measurement point as the measurement point for the master workpiece. Measure the distance to the measurement surface.

Then, the difference between the actual value measured at each measurement point and the initial value is taken as the measurement value at each measurement point, and the measurement value at the first measurement point, the measurement value at the second measurement point, and the measurement at the third measurement point. Calculate the value.
Among the calculated measurement values, the measurement value at the second measurement point, which is the reference point, is defined as a difference between the comparison reference surface and the measurement surface of the measurement target object.

  Next, the inclination angle of the measurement surface with respect to the comparison reference surface of the measurement object is calculated. The inclination angle (Pitch) around the X axis is a known predetermined value between the first measurement point and the second measurement point, the measurement value at the second measurement point as the reference point, and the measurement value at the first measurement point. It calculates with the inverse trigonometric function from the relationship with the difference value. The tilt angle (Roll) about the Y axis is the distance between the second measurement point and the third measurement point, which are known predetermined values, the measurement value at the second measurement point, which is the reference point, and the measurement value at the third measurement point. It calculates with the inverse trigonometric function from the relationship with the difference value.

  If this apparatus is used, there is no need to perform length measurement on the comparison reference plane of the object to be measured as in the prior art, and the measuring means is moved between two surfaces of the comparison reference plane and the measurement plane of the measurement object. Since there is no necessity, the height difference and the inclination angle between both surfaces can be obtained in a short time.

  According to a second aspect of the present invention, there is provided a measuring apparatus for measuring the height difference between the planes and the inclination angle, the measuring object holding means biasing the moving member abutting the measuring object and the moving member toward the surface plate surface. It consists of an elastic body and a universal joint that connects the movable member and the elastic body.

According to this configuration, the positioning of the comparison reference surface of the object to be measured with respect to the surface plate surface of the surface plate means can be performed very simply.
According to a third aspect of the present invention, there is provided a device for measuring a height difference between planes and an inclination angle, the number of distance sensors being equal to the number of measurement points arranged on the measurement surface of the measurement object by the measurement means. .

  With this configuration, the setting of the measurement point is determined by the arrangement position of the distance sensor, and the two axes of the X axis and the Y axis that are orthogonal to each other in the plane parallel to the reference surface of the master plate equivalent to the surface plate surface and the surface plate surface are set. The distance sensors are separated from each other by a predetermined distance, and are arranged on the X axis, the Y axis, and the intersections of the X axis and the Y axis.

  This eliminates the need to move the distance sensor of the measurement means when measuring a plurality of measurement points on the measurement surface, thereby reducing the measurement time and eliminating the mechanism for moving the distance sensor from the measurement means. Therefore, the apparatus can be simplified.

According to a fourth aspect of the present invention, there is provided a method for measuring a height difference between planes and a tilt angle, wherein a measurement target object having a plurality of relatively stationary planes is used as a comparison reference plane, and any other arbitrary Is a method of measuring the height difference and the inclination angle of the measurement surface with respect to the comparison reference surface, using the flat surface of
The master work is pressed against the surface plate surface of the surface plate means with the reference surface, and the distance to a plurality of measurement points on the reference surface of the master work facing the measurement means is measured in a direction parallel to the perpendicular direction of the surface plate surface, The actual measurement value at each measurement point is the initial value of each measurement point, and the distance between each measurement point is set as a known predetermined value.
The object to be measured is pressed against the surface plate of the surface plate means with the comparison reference surface, and the distance to the surface to be measured of the object to be measured facing the measuring means is measured at the same measurement point as the measurement point for the master workpiece. The difference between the measured value measured at the point and the initial value is the measured value at each measuring point,
Among the measurement points, the measurement value at the measurement point used as the reference point is the difference in height between the comparison reference surface and the measurement surface of the object to be measured, and the measurement value at the measurement point used as the reference point and the measurement value at any measurement point The inclination angle of the measurement surface with respect to the comparison reference surface is calculated in the relationship between the difference value and the distance between the measurement point which is a known predetermined value and the measurement point as the reference point.

  According to this configuration, it is possible to perform measurement with high accuracy with respect to the height difference without being affected by the distance between the two surfaces of the comparison reference surface and the measurement surface of the measurement target object.

  As described above, according to the present invention, it is not necessary to measure the comparison reference plane of the measurement target object by positioning the measurement target object in contact with the surface plate surface of the surface plate means on the comparison reference plane, thereby eliminating the need to measure the comparison reference plane of the measurement target object. By measuring the height difference and the tilt angle of the measurement surface of the measurement target object with respect to the surface plate surface of the means, the height difference and the tilt angle between the comparison reference surface and the measurement surface of the measurement target object can be obtained.

  In other words, the distance to the reference surface measured in advance in the master work is taken as the initial value to the surface plate surface and the comparative reference surface, and the difference between the measured value and the initial value of the distance to the measurement surface measured in the object to be measured is calculated. Measured values at multiple measuring points are obtained as measured values, and the measured value at the measuring point as the reference point is not the difference in height between the comparison reference surface and the measuring surface of the object to be measured, and the measured value at the measuring point as the reference point is The inclination angle of the measurement surface with respect to the comparison reference surface can be calculated based on the difference between the measurement value at an arbitrary measurement point and the relationship between the measurement point that is a known predetermined value and the distance between the measurement point as the reference point.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a schematic diagram of an apparatus for measuring the height difference and inclination angle between planes according to an embodiment of the present invention, and FIG. 2 is a diagram of a plurality of relatively immovable planes in a measurement object measured by the apparatus. A definition diagram of a height difference and an inclination angle of an arbitrary plane (hereinafter referred to as a measurement plane) in the object with respect to the same reference plane (hereinafter referred to as a comparison reference plane) when any one plane is used as a reference; FIG. 3 is a perspective view showing an example of an object to be measured, and FIG. 4 is a perspective view of the apparatus.

  1 to 4, an object 1 to be measured is an apparatus that handles an information recording medium as an example, and an S reel 3 and a T reel 4 for feeding and winding a magnetic tape are provided on a base 2, and further magnetic A plurality of guide posts 5 for guiding the tape are provided. For measurement, the upper surfaces of the S reel 3 and the T reel 4 are treated as a plurality of relatively stationary planes as an integral part of the base 2, and the S reel 3 An upper surface of the T reel 4 is a measurement surface 7.

  The measuring device 8 includes a surface plate fixing portion 10 that constitutes a surface plate means standing on the base member 9, a measurement movable portion 13 disposed via an X table 11 and a Y table 12 provided on the base member 9, and a measurement A plurality of distance sensors 14 including a laser distance sensor or the like serving as a measurement unit provided in the movable unit 13 and a lifter unit 16 serving as a measurement target object holding unit that presses the measurement target object 1 against the surface plate fixing unit 10 are provided. .

  The surface plate fixing portion 10 has a surface plate surface 17 at a portion facing the base member 9, and the measurement movable portion 13 has a measurement reference surface 18 at a portion facing the base member 9 and a plurality of distance sensors 14 on the measurement reference surface 18. Is arranged. The positional relationship between the surface plate surface 17 and the measurement reference surface 18 is fixed at the time of measurement. In the present embodiment, both surfaces are assembled in parallel.

  The lifter unit 16 includes a plate 19 that is a movable member that comes into contact with the object 1 to be measured, a guide rod 20 that holds the plate 19 up and down with respect to the base member 9, and the guide rod 20 in a vertical direction within a predetermined angle range. A rod holding hole 21 provided in the base member 9 that is swingably held, a spring 22 as an elastic body that urges the plate 19 toward the surface plate surface 17, and a universal joint that connects the spring 222 and the plate 19. As a floating universal joint 23.

  Here, the definition of the height difference and the inclination angle in the measurement target object 1 in the present embodiment will be described with reference to FIG. In this apparatus, a first distance sensor 15a, a second distance sensor 15b, and a third distance sensor 15c are arranged at three positions on two axes orthogonal to each other on the measurement reference plane 18 of the measurement movable unit 13, respectively. The positional relationship is described below.

  In FIG. 2, a virtual plane S parallel to the measurement reference surface 18 of the measurement movable part 13 which is parallel to the surface plate surface 17 and a reference surface of a master work described later is superimposed on the measurement surface 7 of the measurement target object 1. Assuming that the X axis and Y axis that are orthogonal to each other in the virtual plane S are set, and the intersection point of the X axis and the Y axis is set as a reference point on the Y axis that is separated by a predetermined distance on the X axis and the Y axis. The first measurement point 31, the second measurement point 32 on the intersection of the X axis and the Y axis, and the third measurement point 33 on the X axis are set, and the distance yl between the first measurement point and the second measurement point and the second The distance xl between the measurement point and the third measurement point is set to a known predetermined value.

  The first distance sensor 15a, the second distance sensor 15b, and the third distance sensor 15c pass through the first measurement point 31, the second measurement point 32, and the third measurement point 33, respectively. At each measurement point projected on the measurement surface 7, the measurement surface is in contact with the measurement surface 7 of the measurement target object 1 at the measuring tip, and the distance to the measurement surface 7 of the measurement target object in a direction parallel to the perpendicular direction of the surface plate surface 17. Is measured at the first measurement point 31, the second measurement point 32, and the third measurement point 33. In the present embodiment, the length is measured by a plurality of distance sensors, but a single distance sensor may be moved to the first measurement point 31, the second measurement point 32, and the third measurement point 33.

  The height difference of the measurement surface 7 with respect to the comparison reference surface 6 of the measurement object 1 is Penetration as the value measured at the second measurement point 32, Pitch as the tilt angle around the X axis, and Roll as the tilt angle around the Y axis. Symbols are respectively defined for the directions shown in the figure.

The X table 11 moves the measurement movable unit 13 in the X-axis direction shown in FIG. 2, and the Y table 12 moves the measurement movable unit 13 in the Y-axis direction shown in FIG.
A measurement procedure using the apparatus configured as described above will be described below. In the measurement, the distance to the surface plate surface 17 of the surface plate fixing unit 10 is measured in advance as an initial value of measurement by the first distance sensor 15a, the second distance sensor 15b, and the third distance sensor 15c.

  For this reason, this master work is prepared by cutting a reference surface having no height difference and an inclination angle with respect to the surface plate surface 17, and the reference surface is a single flat surface as a standard. However, as will be described later, the master work faces a region (first reference surface) where the reference surface is pressed against the surface plate surface 17, and the first distance sensor 15a, the second distance sensor 15b, and the third distance sensor 15c. The region (second reference plane) to be used may be a different plane, and a known height difference and inclination angle may be used as a correction value between the two regions. In this case, a measurement value described later is corrected with a correction value.

  At the time of measuring the initial value, the master work is held by the lifter unit 16 while being pressed against the surface plate surface 17 by the reference surface. By this operation, the surface plate surface 17 and the reference surface of the master work have the same positional relationship with no height difference and no inclination angle between them. In this state, assuming that the reference surface of the master work facing the first distance sensor 15a, the second distance sensor 15b, and the third distance sensor 15c is equivalent to the surface plate surface, the distance to the reference surface is the first distance. The output values of the sensor 15a, the second distance sensor 15b, and the third distance sensor 15c are read, and these are read as initial values M1, M2, and M3 at the first measurement point 31, the second measurement point 32, and the third measurement point 33, respectively. And The initial value need not be measured at every measurement, and may be measured at an appropriate time.

  Next, the object to be measured 1 is positioned in contact with the surface plate surface 17 at the comparison reference surface 6 in the same manner as described above. By this operation, the surface plate surface 17 and the comparison reference surface 6 have the same positional relationship with no height difference and no inclination angle between them. For this reason, it is not necessary to measure the comparison reference surface 6 of the measurement target object 1 when measuring the height difference and the tilt angle between the comparison reference surface 6 and the measurement surface 7 of the measurement target object 1, and the measurement target object with respect to the surface plate surface 17. By measuring the height difference and the inclination angle of one measurement surface 7, the height difference and the inclination angle between the comparison reference surface 6 and the measurement surface 7 of the measurement target object 1 can be obtained.

  In this state, the first distance sensor 15a, the second distance sensor 15b, and the distance to the measurement surface 7 of the measurement target object 1 facing the third distance sensor 15c are the first distance sensor 15a and the second distance sensor 15a. The output values of the sensor 15b and the third distance sensor 15c are read, and these are set as the actual measurement values W1, W2, and W3 at the first measurement point 31, the second measurement point 32, and the third measurement point 33, respectively.

  Then, the difference between the measured values W1, W2, W3 measured at the respective measurement points, ie, the first measurement point 31, the second measurement point 32, and the third measurement point 33, and the initial values M1, M2, and M3 is determined at each measurement point. As measurement values, the measurement value (M1-W1) of the first measurement point, the measurement value (M2-W2) of the second measurement point, and the measurement value of the third measurement point (M3-W3) are calculated.

  Among the calculated measurement values, the measurement value (M2-W2) at the second measurement point, which is the reference point, is defined as the elevation difference between the comparison reference surface 6 and the measurement surface 7 of the measurement target object 1 in the following equation.

  Next, the inclination angle of the measurement surface 7 with respect to the comparison reference surface 6 of the measurement target object 1 is calculated. The tilt angle (Pitch) around the X axis is the distance yl between the first measurement point 31 and the second measurement point 32, which is a known predetermined value, and the measurement value (M2-W2) at the second measurement point 32, which is a reference point. ) And the difference value of the measurement value (M1-W1) at the first measurement point 31 is calculated by the inverse trigonometric function of the following equation.

  Next, the inclination angle (Roll) about the Y-axis is a distance xl between the second measurement point 32 and the third measurement point 33, which is a known predetermined value, and a measurement value (second measurement point 32, which is a reference point) ( M2−W2) and the relationship between the measured value (M3−W3) at the third measurement point 33 and the inverse trigonometric function of the following equation.

  In the above-described configuration, an object having a single reference plane and a Penetration, Pitch, and Roll values all zero with respect to the surface plate surface 17 is used as the master workpiece. However, the master workpiece defines the reference plane. A region (first reference surface) pressed against the board surface 17 and a region (second reference surface) facing the first distance sensor 15a, the second distance sensor 15b, and the third distance sensor 15c have different planes. However, it is also possible to use the difference in height and inclination angle between the two regions given as known correction values. In this case, if each correction value is a master work given as Pe, Pi, Ro, it is obvious that the above (Equation 1) to (Equation 3) can be replaced as follows.

  As described above, according to the present invention, it is not necessary to measure the comparison reference plane of the measurement target object by positioning the measurement target object in contact with the surface plate surface of the surface plate means on the comparison reference plane, thereby eliminating the need to measure the comparison reference plane of the measurement target object. By measuring the height difference and inclination angle of the measurement surface of the object to be measured relative to the surface plate surface of the means, the height difference and inclination angle between the comparison reference surface and the measurement surface of the object to be measured can be obtained. Measurement target object having a plurality of stationary planes, and using any one surface as a comparison reference plane, the height difference between any other planes of the measurement target object relative to the reference plane and the inclination angle between the measurement planes It can be used in a difference and angle measuring device and method.

The model figure of the measuring apparatus of the elevation difference between planes and inclination-angle concerning embodiment of this invention Definition of measurement surface height difference and tilt angle according to the same embodiment A perspective view showing an example of an object to be measured The perspective view of the measuring device of the height difference between planes and an inclination angle concerning the embodiment

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Measurement object 2 Base 3 S reel 4 T reel 5 Guide post 6 Comparison reference plane 7 Measurement surface 8 Measurement apparatus 9 Base member 10 Surface plate fixed part 11 X table 12 Y table 13 Measurement movable part 14 Distance sensor 15a 1st Distance sensor 15b Second distance sensor 15c Third distance sensor 16 Lifter portion 17 Surface plate surface 18 Measurement reference surface 19 Plate 20 Guide rod 21 Rod holding hole 22 Spring 23 Floating universal joint 31 First measurement point 32 Second measurement point 33 Third measurement point

Claims (4)

Measure the height difference and tilt angle of the measurement surface with respect to the comparison reference plane, using any one plane as the comparison reference plane and any other plane as the measurement plane in the measurement target object having a plurality of relatively stationary planes. A device,
A surface plate means having a surface plate as an inspection reference, a measurement object holding means for holding the object to be measured in contact with the surface plate surface of the surface plate means on the comparison reference surface, and a perpendicular direction of the surface plate surface of the surface plate means Measuring device for measuring the difference in height and inclination angle between planes, comprising measuring means for measuring the distance to the measurement surface of the object to be measured at a plurality of measurement points in a direction parallel to the plane. The measurement object holding means includes a movable member that comes into contact with the measurement object, an elastic body that urges the movable member toward the surface plate, and a universal joint that connects the movable member and the elastic body. The apparatus for measuring a height difference between planes and a tilt angle according to claim 1. 3. The apparatus for measuring height difference and inclination angle between planes according to claim 1, wherein the measuring means has a number of distance sensors equal to the number of measurement points arranged on the measurement surface of the object to be measured. Measure the height difference and tilt angle of the measurement surface with respect to the comparison reference plane, using any one plane as the comparison reference plane and any other plane as the measurement plane in the measurement target object having a plurality of relatively stationary planes. A method,
The master workpiece is pressed against the surface plate surface of the surface plate means with the reference surface, and the distance to a plurality of measurement points on the reference surface of the master workpiece facing the measuring means is measured in a direction parallel to the perpendicular direction of the surface plate surface, The actual measurement value at each measurement point is the initial value of each measurement point, and the distance between each measurement point is set as a known predetermined value.
The object to be measured is pressed against the surface plate of the surface plate means with the comparison reference surface, and the distance to the surface to be measured of the object to be measured facing the measuring means is measured at the same measurement point as the measurement point for the master workpiece. The difference between the measured value measured at the point and the initial value is the measured value at each measuring point,
Among the measurement points, the measurement value at the measurement point used as the reference point is the difference in height between the comparison reference surface and the measurement surface of the object to be measured, and the measurement value at the measurement point used as the reference point and the measurement value at any measurement point Difference in height between planes characterized by calculating the inclination angle of the measurement surface with respect to the comparison reference surface in the relationship between the difference value and the distance between the measurement point that is a known predetermined value and the measurement point as the reference point And measuring method of tilt angle.

Images