JP2016070662A - Surface roughness measuring instrument - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a surface roughness measuring instrument that can measure and evaluate surface roughness of a peripheral surface of a measured object composed of a spherical body or rotor with accuracy and evaluation reference equal to a case where surface roughness of a flat surface of the measured object is measured, and causes no increase in size of a device or cost increase.SOLUTION: In a surface roughness measuring instrument 1, a work installation plate 48 supports a part on a lower side of a peripheral surface of a work W as a first portion, and, as coming into contact with a second portion which is a part on an upper side of the peripheral surface of the work W, a rubber part 86 moves in a direction orthogonal to a rotation axis of the work W by a drive unit, which in turn the work W is rotated. Then, a detector 30 is anchored at a position opposing to a third portion which is a part on the lower side of the peripheral surface of the work W to detect surface roughness in a circumferential direction of the peripheral surface of the work W.SELECTED DRAWING: Figure 6

Description

  The present invention relates to a surface roughness measuring machine, and more particularly to a surface roughness measuring machine that measures the surface roughness of a workpiece (workpiece) made of a rotating body such as a sphere or a cylinder or a cylinder with high accuracy.

  A surface roughness measuring instrument moves a detector (a detector (pickup) that detects the amount of displacement of the tip of the measuring element) having a measuring element (stylus) along the surface of the object to be measured (workpiece), and performs measurement. It is a device that measures the surface roughness, surface shape, and the like of a workpiece by converting the amount of displacement of the tip of the child into an electric signal and reading it into an arithmetic processing device (computer) such as a computer.

  For example, Patent Documents 1 and 2 disclose a surface roughness measuring machine having a well-known configuration. The surface roughness measuring machine is a horizontal upper surface (a plane parallel to the X axis and the Y axis) on which a workpiece is placed. ), A column extending in the Z-axis direction provided upright on the base, a drive unit supported by the column and moved up and down in the Z direction by the Z drive mechanism of the column, and a drive unit supported by the drive unit It has a detector (pickup) that moves in the X-axis direction by the X drive mechanism, and a data processing unit that acquires measurement signals output from the detector and performs various arithmetic processes. The detector has a probe (stylus) extending in the X-axis direction, and a stylus extending in the Z-axis direction is provided as a tip portion thereof.

  According to such a surface roughness measuring machine, the position (height) of the detector in the Z-axis direction is adjusted by the Z drive mechanism of the column, and the tip of the measuring element is placed on the surface of the workpiece placed on the base. Is set in a contact state. Then, the entire detector is moved at a constant speed in the X-axis direction by the X drive mechanism of the drive unit, and the tip of the measuring element is moved by a predetermined distance in the X-axis direction and stopped while sliding on the workpiece surface.

  In this way, when the tip of the probe is moving on the scanning line in the X-axis direction on the workpiece surface, the detector indicates the amount of displacement in the Z-axis direction of the tip of the probe. A signal is output and acquired by the data processor.

  As a result, in the data processing section, from the position of the workpiece surface (measurement start position) that the tip of the probe contacted at the start of measurement to the position of the workpiece surface (measurement end position) that was in contact at the end of measurement. The displacement amount in the Z direction of the tip of the probe at each measurement point on the scanning line along the X-axis direction is acquired as a value indicating the uneven state in the Z-axis direction of the workpiece surface at each measurement point. Based on the data indicating the surface shape of the workpiece, various evaluation values indicating the surface roughness (specified parameters such as arithmetic average roughness and maximum height) are calculated, and the acquired or calculated data is monitored. Is displayed.

  In such a surface roughness measuring instrument, when the workpiece to be measured is a sphere or a rotating body, the tip of the measuring element is on the workpiece surface except for the vertex of the workpiece (the point where the X-axis direction is a tangent). On the other hand, the surface of the workpiece is not contacted vertically, and the surface of the workpiece cannot be detected vertically. In addition, only a part of the peripheral surface of the workpiece can be measured by simply moving the tip of the probe linearly in the X-axis direction.

  Therefore, when measuring the surface roughness of the peripheral surface of the work over the entire circumference in the circumferential direction, a method of measuring the work multiple times by rotating the work index is proposed (see Patent Document 3). However, this method has a problem that it takes time and effort because it is necessary to synthesize results obtained by a plurality of measurements.

  As a technique to solve this problem, the workpiece is rotated so that the tip of the probe moves relatively along the circumferential direction on the circumferential surface of the workpiece, and the surface roughness in the circumferential direction of the circumferential surface of the workpiece Have been proposed in Patent Documents 4 and 5.

  Patent Documents 4 and 5 include a rotation driving device that rotates a spherical or rotating workpiece, and the rotation driving device includes two rollers whose axial directions are parallel to each other on the same horizontal plane. A motor for rotationally driving the roller. The workpiece is placed in a state of being supported from the two lower directions between the two rollers. On the other hand, the tip of the measuring element is brought into contact with the uppermost point in the Z-axis direction of the work placed on the roller.

  Thereby, the work can be rotated in conjunction with the rotation of the roller, and the tip of the measuring element can be relatively moved along the circumferential direction of the peripheral surface of the work.

  Patent Documents 6 and 7 disclose apparatuses that measure the surface roughness (surface roughness) of a rotating body workpiece in-process at the time of workpiece machining in a machining apparatus such as a cylindrical grinding machine.

JP 2002-107144 A JP 2006-300823 A Japanese translation of PCT publication No. 6-507706 JP-A-2-129509 Japanese Patent Laid-Open No. 3-9209 Japanese Patent Laid-Open No. 10-138095 Japanese Patent Laid-Open No. 2005-016972

  When measuring the surface roughness in the circumferential direction of the circumferential surface of a spherical or rotating workpiece, the workpiece is moved so that the tip of the probe moves relatively along the circumferential direction on the circumferential surface of the workpiece. A rotation drive mechanism for rotating the is required.

  However, the rotation drive devices described in Patent Documents 4 and 5 are newly added with a rotation drive mechanism for rotating a workpiece with respect to the surface roughness measuring machine as described in Patent Documents 1 and 2. When rotating the workpiece with high accuracy, an expensive bearing mechanism is also required, which increases the size of the surface roughness measuring machine and increases the cost.

  In Patent Documents 6 and 7, since a measuring machine is incorporated in the machining apparatus, a rotation drive mechanism for rotating the workpiece can be used as a component of the machining apparatus, but can be incorporated in the machining apparatus. There is a limitation of being a premise. Further, when viewed as a surface roughness measuring machine, a rotation driving mechanism for a workpiece is newly added as in Patent Documents 4 and 5, which increases the size of the surface roughness measuring machine and increases the cost.

  Moreover, when measuring the surface roughness of the flat surface of a workpiece | work with surface roughness measuring machines like patent document 1, 2, as mentioned above, a data processing part is a detector (tip of a measuring element) by a drive part. The measurement signal from the detector when the part is moving at a constant speed in the X-axis direction is acquired. At this time, the value obtained by multiplying the elapsed time from the start of measurement by the movement speed of the detector is the movement of the tip of the probe moved along the scanning line from the measurement start position (at the start of measurement) by that elapsed time. This represents the amount (movement distance) and corresponds to the position of the measurement point on the surface of the workpiece that is in contact with the tip of the measuring element at the elapsed time, expressed by the length of the scanning line from the measurement start position.

  From such a relationship, the data processing unit associates the signal value of the measurement signal at each measurement point on the workpiece surface sequentially obtained from the detector with the length of the scanning line from the predetermined reference position to each measurement point. Have acquired. In the case of a workpiece having a flat surface (measurement surface), since the scanning line is parallel to the X-axis direction, the length of the scanning line from the predetermined reference position to the measurement point is from the predetermined reference position to the measurement point. The position of each measurement point is represented by an X coordinate value with respect to a predetermined origin position. Further, the position of the measurement point can be similarly obtained by acquiring the position of the detector (position in the X-axis direction) from the position sensor, not from the moving speed of the detector and the elapsed time.

  In addition, the data processing unit, for example, samples the measurement signal of the analog signal from the detector at a predetermined time period, acquires it by converting it into a digital signal by A / D conversion, and the movement speed of the detector, By adjusting the sampling period (time period), the signal value of the measurement signal at the measurement points at predetermined intervals on the scanning line is acquired.

  On the other hand, when measuring the work peripheral surface of a sphere or rotating body in the circumferential direction, each measurement point on the scanning line along the circumferential direction on the work peripheral surface is the same as when measuring a flat work surface. The signal value of the measurement signal is acquired in association with the length of the scanning line from the predetermined reference position to each measurement point (periphery of the measurement surface), and measurement is performed at measurement points at every desired length of the scanning line. It is desirable to be able to acquire (sample) the signal value of the signal. As a result, even if the measurement surface is a spherical or rotating work peripheral surface, the surface roughness can be evaluated by the same evaluation criteria as in the case of a flat work surface.

  However, when the work is rotated by rotation of a roller or the like in a rotation drive mechanism that supports the work as in Patent Document 4-7, the measurement points on the scanning line along the circumferential direction of the work peripheral surface are measured. The length of the scanning line depends on the value of the workpiece (workpiece peripheral surface) or roller diameter multiplied by their rotation speed and the elapsed time from the start of measurement. Information is required. These pieces of information are unnecessary information in the case of a flat workpiece surface. If these pieces of information are obtained in advance by manual input by the user, the work requires time and the position of the measurement point. This increases the error with respect to the actual position.

  On the other hand, conventionally, the position of the measurement point is represented by the rotation angle of the workpiece or roller obtained by multiplying the rotation speed and the elapsed time, and the signal value of the measurement signal at each measurement point corresponds to the rotation angle of the workpiece, etc. In general, the surface roughness is evaluated as a result of the evaluation, and there is a problem that it is not possible to make a judgment on whether or not the surface roughness is evaluated.

  Further, in Patent Document 4-7, there is a support point that supports the workpiece at a position that is 180 ° opposite to the circumferential direction with respect to the position of the measurement point on the workpiece circumferential surface that is in contact with the tip of the measuring element. Not done. For this reason, there is a problem that vibration is likely to occur in the orthogonal direction at the measurement point on the work peripheral surface, and an error is likely to occur.

  The present invention has been made in view of such circumstances, and has the same accuracy and evaluation standard as those used when measuring the surface roughness of a flat surface of the object to be measured. An object of the present invention is to provide a surface roughness measuring machine that can measure and evaluate the surface roughness of a surface and that does not increase the size of the apparatus or increase the cost.

  In order to achieve the above object, a surface roughness measuring instrument according to an aspect of the present invention includes a supporting unit that supports a first part that is a part of a peripheral surface of a measurement object including a sphere or a rotating body, and a measurement target. Rotating means for rotating the object to be measured by moving in a direction orthogonal to the rotation axis of the object to be measured while contacting a second part which is another part of the peripheral surface of the object, and a periphery of the object to be measured Detecting means for detecting the surface roughness in the circumferential direction of the peripheral surface of the object to be measured, which is disposed and fixed at a position facing the third part which is still another part of the surface.

  According to the present invention, as in the case of measuring the surface roughness of a flat surface, the position of each measurement point on the scanning line along the circumferential direction of the circumferential surface of the non-measurement object is set to the diameter of the non-measurement object. Regardless of the above, based on the moving speed of the rotating means in the direction orthogonal to the rotation axis of the non-measurement object and the elapsed time from the start of measurement, the length of the scanning line from the predetermined reference position (peripheral length And the signal value of the measurement signal output from the detection means can be acquired in association with the length of the scanning line.

  In addition, when the measurement signal of the analog signal is sampled at a predetermined time period and converted into a digital signal by A / D conversion, the moving speed and sampling of the rotating means are sampled as in the case of measuring the surface roughness of the flat surface. By adjusting the period (time period), the signal value of the measurement signal at the measurement points at predetermined intervals on the scanning line can be acquired.

  Therefore, even if the measurement surface is a sphere or a peripheral surface of a rotating body, the surface roughness can be evaluated based on the same evaluation criteria as in the case of a flat surface. In addition, information such as the diameter of an object to be measured that is not necessary for measuring the surface roughness of a flat surface is also unnecessary, so there is no need for the user to manually input the information in advance, and the measurement results can be processed. There is no increase in error factors.

  In addition, since the rotating means can be configured by using a driving means that is used when measuring the surface roughness of a flat surface and moves the detecting means straight, the apparatus of the surface roughness measuring machine Does not lead to an increase in size and cost.

  In the surface roughness measuring machine according to one aspect of the present invention, the rotating means is a flat surface parallel to the rotation axis, which is in contact with the object to be measured, and the contact surface along the flat surface. And a driving means for moving straightly in the selected direction.

  In the surface roughness measuring instrument according to one aspect of the present invention, the third part can be an aspect that is 180 degrees opposite to the second part in the circumferential direction.

  According to this aspect, it is difficult for vibration to occur in the third region where the surface roughness is measured by the detection means, which contributes to improvement in measurement accuracy.

  In the surface roughness measuring machine according to one aspect of the present invention, the detection means may be an aspect of a contact type detection means having a measuring element whose tip is in contact with the third part.

  In the surface roughness measuring machine according to one aspect of the present invention, the rotating means may be provided with a pressurizing means that pressurizes the object to be measured via a contact surface that contacts the object to be measured.

  In the surface roughness measuring instrument according to an aspect of the present invention, the support means includes a plate-like body having a tapered hole into which a part of the peripheral surface of the sphere enters when the object to be measured is a sphere. It can be.

  In the surface roughness measuring machine according to another aspect of the present invention, the support means includes a tapered groove into which a part of the range along the rotation axis of the peripheral surface of the rotating body enters when the object to be measured is a rotating body. It can be set as the aspect which has.

  According to the present invention, it is possible to measure and evaluate the surface roughness of the peripheral surface of a measured object made of a sphere or a rotating body with the same accuracy and evaluation standard as when measuring the surface roughness of a flat workpiece surface. In addition, it is possible to prevent an increase in size and cost of the apparatus.

Front view of a surface roughness measuring machine to which the present invention is applied Right side view of a surface roughness measuring machine to which the present invention is applied The front view which expanded and showed the detector support mechanism of FIG. Top view showing the central part of the workpiece installation table in an enlarged manner Sectional view along arrow 5-5 in FIG. Enlarged view showing the arrangement of the workpiece, detector, and pressure unit during measurement Plan view showing workpiece installation plate when measuring circumferential surface roughness of cylindrical workpiece surface 8-8 arrow sectional view in FIG. The conceptual diagram which simplified and showed the surface roughness measuring machine of FIG. Conceptual diagram showing another embodiment of the surface roughness measuring instrument in a simplified manner Conceptual diagram showing another embodiment of the surface roughness measuring instrument in a simplified manner

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

  1 and 2 are a front view and a side view of a surface roughness measuring machine to which the present invention is applied. The surface roughness measuring machine 1 shown in these drawings is a device that measures the surface roughness in the circumferential direction of the circumferential surface of a spherical workpiece, and includes a measuring unit 2 that measures the surface shape of the measuring surface, and a measuring unit 2. And a data processing unit 3 for processing the data obtained by the above. The data processing unit 3 is provided as part of the function of an arithmetic processing device such as a personal computer. In the following, when the surface roughness measuring device 1 is simply referred to, the measuring unit 2 is mainly shown. In FIG. 2, the data processing unit 3 is omitted.

  The surface roughness measuring machine 1 includes a base 4 having a flat upper surface arranged along the horizontal direction (X-axis direction and Y-axis direction), and fixed to the base 4 along the vertical direction (Z-axis direction). And a column 5 erected. On the upper surface of the base 4, a detector support mechanism 10 that supports a detector 30 (detection means that is also referred to as a pickup) and a work support mechanism that supports a spherical workpiece W (see FIG. 6 described later) as a measurement target. 40 (support means) is provided, and the column 5 is provided with a work drive mechanism 70 (rotation means) for rotating the work W supported by the work support mechanism 40.

  First, the detector support mechanism 10 will be described with reference to the front view of FIG. 3 in which only the detector support mechanism 10 is enlarged. On the upper surface of the base 4, a flat first rectangular fixed plate 12 is formed. Is fixed, and a flat and rectangular second fixing plate 14 having a smaller surface area than the first fixing plate 12 is fixed to the upper surface of the first fixing plate 12. As shown in FIG. 2, the first fixing plate 12 is fixed to the base 4 with a screw in a state of being engaged with a rectilinear groove 4A formed along the X-axis direction, and the first fixing plate 12 is first fixed by loosening the screw. The plate 12 can be moved in the X-axis direction along the rectilinear groove 4A. As a result, the fixed positions in the X-axis direction of the base 4 of the detector support mechanism 10 and the workpiece support mechanism 40 are adjusted as a whole.

  An XYZ stage 16 is fixed on the upper surface of the second fixed plate 14, and a detector 30 is supported on the upper part of the XYZ stage 16. As the XYZ stage 16, a well-known and arbitrary structure can be used, and detailed description is omitted. However, when the Y knob 18A (see also FIG. 2) is rotated, the Y stage 18B becomes the second fixed plate. 14, the detector 30 moves in the Y-axis direction. When the X knob 20A is rotated, the X stage 20B moves in the X axis direction with respect to the Y stage 18B, and the detector 30 moves in the X axis direction. When the Z knob 22A is rotated, the Z stage 22B moves in the Z axis direction with respect to the X stage 20B, and the detector 30 moves (moves up and down) in the Z axis direction. The X axis, the Y axis, and the Z axis are orthogonal to each other, the X axis and the Y axis indicate a horizontal direction parallel to the horizontal plane (the upper surface of the base 4), and the Z axis indicates a vertical direction orthogonal to the horizontal plane. Show.

  The detector 30 can also be a well-known and arbitrary structure, and although detailed description is omitted, a cylindrical detector body 32 and a rod-shaped measurement extending from the tip of the detector body 32 And a child 34 (stylus). A detector holder 24 is fixed to the upper part of the Z stage 22B of the XYZ stage 16, and the detector 30 is supported on the XYZ stage 16 by fixing the detector main body 32 to the detector holder 24. .

  The measuring element 34 of the detector 30 is arranged in a direction orthogonal to the Y axis and substantially parallel to the X axis. Furthermore, a stylus 36 that protrudes in a direction orthogonal to the stylus 34 and contacts the surface (circumferential surface) of the workpiece W is provided at the tip of the stylus 34, and the stylus 36 is in the Y-axis. In a direction perpendicular to the Z axis, substantially parallel to the Z axis and upward.

  Next, the work support mechanism 40 will be described. As shown in FIGS. 1 and 2, a work setting table 46 is provided on the upper surface of the second fixing plate 14 to which the XYZ stage 16 is fixed. The workpiece mounting base 46 is fixed to the second fixing plate 14 and is erected along the vertical direction (Z-axis direction), and has two leg portions 42 disposed opposite to each other in the Y-axis direction, and two It has a support portion 44 that is fixed to the upper end portion of the leg portion 42 and spans horizontally (Y-axis direction).

  In addition, the workpiece mounting base 46 is disposed across the stylus 36 of the probe 34 in the detector 30, and the support portion 44 is disposed above the stylus 36.

  4 is an enlarged top view showing the vicinity of the central portion of the workpiece mounting table 46, and FIG. 5 is a cross-sectional view taken along the arrow 5-5 in FIG. As shown in these drawings, a through groove 44A (broken line) penetrating in the Z-axis direction extending in the X-axis direction is formed at the center of the support portion 44, and the through-groove 44A is formed on the upper surface of the support portion 44. A disc-shaped workpiece installation plate 48 is detachably fixed to the overlapping portion with screws 50, 50 with knobs. In addition, positioning pins 52 and 52 protrude from two positions on the upper surface of the support portion 44, and are fixed to the support portion 44 in a state where the outer peripheral edge of the workpiece installation plate 48 is in contact with the positioning pins 52 and 52. As a result, the workpiece setting plate 48 is positioned at the specified position of the support portion 44.

  A taper-shaped taper hole 48 </ b> A that penetrates in the Z-axis direction and has an enlarged diameter toward the upper side is provided at the center of the work installation plate 48. The lower opening of the taper hole 48A is disposed near the center of the support portion 44 of the workpiece mounting base 46, and the taper hole 48A communicates with the through groove 44A.

  As shown in FIG. 5, a spherical workpiece W to be measured is placed in the tapered hole 48A, and a portion below the center position of the workpiece W enters the tapered hole 48A. The inclined surface of the taper hole 48A contacts the peripheral surface of the workpiece W from the lower oblique direction over the entire circumference around the vertical axis. As a result, the workpiece W is placed in a state in which the downward movement of the workpiece W in the vertical direction (Z-axis direction) and the horizontal direction (X-axis direction and Y-axis direction) are restricted by the tapered hole 48A. Supported by the plate 48. At this time, the lower apex (lowermost point) of the peripheral surface of the workpiece W is disposed near the lower opening of the tapered hole 48A. As a result, the arrangement of the workpiece W and the detector 30 at the time of measurement is shown, and the tip of the probe 34 in the detector 30 is located on the lower vertex of the peripheral surface of the workpiece W as shown in FIG. The stylus 36 can come into contact.

  A plurality of types of workpiece installation plates 48 having different plate thicknesses, taper hole 48A sizes, slope inclinations, etc. are prepared, and those of an appropriate type are selected according to the diameter of the workpiece W to be measured. It can be installed on the support portion 44 of the installation table 46. As a work installation plate 48 suitable for the work W, when the work W is placed in the tapered hole 48A, the peripheral surface of the work W is at least the upper edge or the lower edge of the taper hole 48A of the work installation plate 48. Preferably, the taper comes into contact with the center of the inclined surface of the tapered hole 48A in the vertical direction, and the lower apex (lowermost point) of the peripheral surface of the workpiece W is a height near the lower end of the tapered hole 48A. (The height in the vicinity of the lower surface of the workpiece installation plate 48) and the upper vertex (uppermost point) of the peripheral surface of the workpiece W is above the upper end of the taper hole 48A (the upper surface position of the workpiece installation plate 48). Applicable to height.

  Next, the workpiece drive mechanism 70 will be described. As shown in FIGS. 1 and 2, the column 5 supports a drive unit 72 (feed device as drive means) so as to be movable up and down in the Z-axis direction.

  An arm 74 projects from the lower side of the drive unit 72, and pressurization is performed at the lower end of the arm 74 to press the workpiece W supported by the workpiece installation plate 48 of the workpiece support mechanism 40 from above. The unit 76 is fixed.

  On the other hand, a motor that moves the drive unit 72 up and down is mounted inside the column 5, and a motor that moves the arm 74 in the X-axis direction is mounted inside the drive unit 72. These motors are driven in accordance with a control signal from the arithmetic processing device or according to a control signal based on a user operation from the controller 6 installed in the base 4, and the drive unit 72 moves along the column 5 along the Z axis. The arm 74 moves up and down in the direction and moves straight in the X-axis direction.

  Therefore, the pressurizing unit 76 is supported by the column 5 and the drive unit 72 so as to be movable in the Z-axis direction and movable in the X-axis direction.

  As the drive unit 72, as is well known, when measuring the surface roughness of a flat workpiece surface, a drive unit that holds the detector 30 and moves the detector 30 straight in the X-axis direction is used. It can be used as a component that is not newly added to measure the surface roughness of the peripheral surface of the spherical workpiece W as in the present embodiment.

  The pressurizing unit 76 is fixed to the arm 74 of the driving unit 72, has a rod-like support part 78 extending along the X-axis direction, and a pressurizing part 80 (pressurizing means) is provided at the tip thereof. .

  As shown in the enlarged view of FIG. 6 showing the arrangement state of the workpiece W, the detector 30, and the pressurizing unit 80 at the time of measurement, the pressurizing unit 80 is the axis of the tip 78A of the support unit 78. A quadrangular columnar (cantilever type) spring portion 82 extending from the position in the X-axis direction and elastically deformable, and a hard, square-columnar tip support portion 84 extending in the X-axis direction from the tip of the spring portion 82; A rubber portion 86 fixed to the lower surface side of the tip support portion 84 and having a rectangular flat contact surface long in the X-axis direction as a lower surface. At the time of measurement, the contact surface of the rubber portion 86 contacts the upper apex (uppermost point) of the work W supported by the work setting plate 48 of the work support mechanism 40, and pressurizes the work W from the upper side.

  In addition, an index needle 88 extending to the vicinity of the tip portion 78A of the support portion 78 is fixed to the tip support portion 84 via the spring portion 82, and a pressure alignment mark 90 is written on the tip portion 78A of the support portion 78. Is done. The indication position of the index needle 88 and the position of the pressurization position alignment mark 90 indicate that the spring portion 82 is elastically deformed when the rubber portion 86 is brought into contact with the work W to pressurize, so that an optimal pressurization state is achieved. When it becomes, it corresponds in the vertical direction.

  The pressure unit 80 includes a stopper unit 92, and the stopper unit 92 includes an arm member 94 and a stopper 96. The arm member 94 is fixed to the upper surface side of the tip portion 78A of the support portion 78, bends in an L shape, and extends in the X-axis direction above the spring portion 82 and the tip support portion 84. The stopper 96 is attached to the distal end portion of the arm member 94, has a convex portion downward, and is opposed to the upper surface of the distal end support portion 84 with a gap. When the workpiece W is pressed by the rubber portion 86, the spring portion 82 is elastically deformed and the tip support portion 84 is displaced upward by a certain amount with respect to the support portion 78, so that the upper surface of the tip support portion 84 contacts the stopper 96. Further displacement is restricted in contact.

  Further, the distal end portion 78A of the support portion 78 is rotated within a range of about 90 degrees around the rotation axis with the Y axis direction as the rotation axis with respect to the base end portion 78B of the support portion 78 by loosening the screw 98 with the knob. As shown in FIG. 6, the pressurizing unit 80 is supported upward from the axial direction of the support unit 78 from the state in which the pressurization unit 80 is supported in the axial direction of the support unit 78 as shown in FIG. 6. You can switch to the state. Accordingly, it is possible to facilitate the work of placing the workpiece W on the workpiece setting plate 48 of the workpiece support mechanism 40 or taking it out of the workpiece setting plate 48 before the measurement is started or after the measurement is completed.

  The operation at the time of measuring the surface roughness in the circumferential direction of the peripheral surface of the spherical workpiece W by the surface roughness measuring machine 1 configured as described above will be described.

  As shown in FIG. 6, first, the operator places the spherical workpiece W to be measured at the position of the tapered hole 48 </ b> A in the workpiece installation plate 48 of the workpiece support mechanism 40. Then, the position of the detector 30 is adjusted by operating the XYZ stage 16, and the stylus 36 of the probe 34 is brought into contact with the lower apex of the workpiece W from the lower side of the workpiece setting plate 48 and the workpiece setting table 46.

  Further, by operating the input device or the like of the arithmetic processing unit having the controller 6 or the data processing unit 3, the position of the drive unit 72 in the Z-axis direction and the position of the arm of the drive unit 72 in the X-axis direction are adjusted, and the pressurizing unit The lower surface of the rubber part 86 in the pressure part 80 of 76 is brought into contact with the upper vertex of the work W from above. Then, the pressure unit 76 is lowered until the support position of the index needle 88 coincides with the position of the pressure alignment mark 90. Thereby, the rubber part 86 and the workpiece W are frictionally engaged, and the workpiece W is pressed against the workpiece installation plate 48 with an appropriate pressure.

  Since the contact surface (lower surface) of the rubber portion 86 is horizontal, if the range in the X-axis direction and the Y-axis direction is set to a position including the upper vertex of the workpiece W, the rubber is formed at the upper vertex of the workpiece W. The abutment surface of the portion 86 can be brought into contact, and high-precision adjustment is unnecessary. Further, it is assumed that the position on the base end side (the support portion 78 side) in the range of the contact surface of the rubber portion 86 is in contact with the workpiece W.

  Subsequently, when the controller 6 or the input device of the arithmetic processing unit having the data processing unit 3 is operated to give an instruction to start measurement, the drive unit 72 goes straight in the X-axis direction at a constant speed of the pressurizing unit 76. Start moving. Here, the direction from the distal end side to the proximal end side of the pressure unit 76 (rightward in FIG. 6) is defined as the traveling direction.

  As a result, when the rubber portion 86 of the pressurizing unit 76 moves in the X-axis direction at a constant speed, the workpiece W is caused to rub with the rubber portion 86 so that the central axis parallel to the Y-axis (of the workpiece W Rotate around an axis that passes through the center and is parallel to the Y axis. As a result, the position of the peripheral surface in a central cross section (surface passing through the center of the workpiece W and parallel to the XY plane) parallel to the XZ plane of the workpiece W of the detector 30 is used as a scanning line on the scanning line. The stylus 36 of the probe 34 moves relatively while sliding.

  At this time, the detector 30 detects the amount of displacement of the stylus 36 of the probe 34 in the Z-axis direction, and a measurement signal indicating the amount of displacement is output from the detector 30.

  The data processing unit 3 acquires the measurement signal output from the detector 30, and various evaluation values (specified parameters such as arithmetic average roughness and maximum height) indicating the surface roughness based on the acquired measurement signal. Calculation, display of the acquired or calculated data on a monitor, etc. are performed.

  According to the configuration and operation of the surface roughness measuring machine 1 described above, the driving unit is used when measuring the surface roughness of a flat workpiece surface, and the driving unit moves the detector straight with respect to the workpiece surface. Is used as the drive unit 72 to rotate the spherical workpiece W, and a rotation drive mechanism for rotating the workpiece W is not newly added except for a part thereof. There is an advantage that it does not increase in size and cost. However, the drive part 72 does not necessarily need to be a drive part used when measuring the surface roughness of a flat workpiece surface.

  Similarly to the case of measuring a flat workpiece surface, the data processing unit 3 relates the position of each measurement point on the scanning line along the circumferential direction of the circumferential surface of the workpiece W to the diameter of the workpiece W or the like. Rather, based on the moving speed of the rubber part 86 by the drive part 72 and the elapsed time from the start of measurement, or based on the position in the X-axis direction of the rubber part 86 that can be acquired from the position sensor, The signal value of the measurement signal output from the detector 30 can be acquired in correspondence with the length of the scanning line (peripheral length).

  Further, when the data processing unit 3 (or the detector 30) samples the measurement signal of the analog signal at a predetermined time period and converts it into a digital signal by A / D conversion, the moving speed of the rubber part 86 and the sampling period (time) By adjusting (cycle), the signal value of the measurement signal at the measurement points at predetermined lengths on the scanning line can be obtained in the same manner as when measuring a flat workpiece surface.

  Accordingly, even if the measurement surface is a spherical or rotating workpiece peripheral surface, the surface roughness can be evaluated by the same evaluation criteria as in the case of a flat workpiece surface. Also, unnecessary information such as the diameter of the workpiece W is not necessary in the measurement of the surface of the flat workpiece, so that there is no need for the user to manually input the information in advance and the cause of the error in the measurement result. Will not increase.

  Furthermore, the measurement point at which the stylus 36 of the probe 34 of the detector 30 contacts the workpiece W, that is, the upper vertex of the workpiece W that is 180 ° opposite to the lower vertex of the workpiece W in the circumferential direction. Since the rubber part 86 of the pressurizing unit 76 contacts and supports the work W as a support point, vibrations hardly occur in the orthogonal direction at the measurement point on the peripheral surface of the work W. Further, vibration that may be transmitted to the workpiece W is absorbed by the rubber portion 86 and the spring portion 82 of the pressure unit 76. Therefore, there is little noise of the measurement signal due to the vibration of the workpiece W, and highly accurate measurement is possible.

  In the above embodiment, the surface roughness measuring machine 1 that measures the surface roughness of a spherical workpiece W as a measurement target has been described. However, the workpiece setting plate 48 of the workpiece setting table 46 in the workpiece support mechanism 40 is a cylindrical body. By using a rotating body such as a cylindrical body, the surface roughness in the circumferential direction of the peripheral surface of the rotating body can be measured in the same manner as in the above embodiment.

  FIG. 7 is a plan view showing a work installation plate 48 corresponding to the work W of the rotating body (cylindrical body), and FIG. 8 is a cross-sectional view taken along arrow 8-8 in FIG. As shown in these drawings, a taper (V-shaped) taper groove 48B extending in a straight line is formed in the workpiece installation plate 48, and the measurement is performed in the center in the longitudinal direction of the taper groove 48B in the Z-axis direction. A working hole 48C is formed.

  When the workpiece setting plate 48 is fixed to the support portion 44 of the workpiece setting table 46 (see FIG. 6), the longitudinal direction of the tapered groove 48B is arranged along the Y-axis direction, and is below the measurement hole 48C. The opening is disposed near the center of the support portion 44 and communicates with the through groove 44A.

  According to this, when the work W of the rotating body is placed so that its rotation axis (center axis) is along the longitudinal direction of the taper groove 48B, the portion below the rotation axis position of the work W is the taper groove 48B. Get in. The inclined surface of the taper groove 48B is contacted with the peripheral surface of the workpiece W obliquely from the lower two directions so that the rotation axis of the workpiece W is in the Y-axis direction, so that the workpiece W becomes the workpiece installation plate 48. Supported.

  At the time of measurement, the stylus 36 of the probe 34 of the detector 30 is inserted from below the measurement hole 48C and brought into contact with the lower apex of the work W, and the contact surface of the rubber portion 86 of the pressure unit 76 Is brought into contact with the upper apex of the workpiece W. Then, by moving the rubber part 86 of the pressurizing unit 76 in the X-axis direction, the work W is rotated around a rotation axis parallel to the Y-axis by frictional engagement between the work W and the rubber part 86. The surface roughness in the circumferential direction of the peripheral surface of the workpiece W can be measured by the detector 30.

  Moreover, the surface roughness measuring machine which concerns on this invention should just be provided with the following structural requirements (1)-(3), and is not limited to the said embodiment.

(1) Support means for supporting a first part that is a part of the peripheral surface of the object to be measured, which is a sphere or a rotating body. (2) Contact with a second part that is another part of the peripheral surface of the object to be measured. Rotating means for rotating the object to be measured by moving in a direction orthogonal to the rotation axis of the object to be measured. (3) Third part which is still another part of the peripheral surface of the object to be measured Is a detection means for detecting the surface roughness in the circumferential direction of the peripheral surface of the object to be measured. That is, the surface roughness measuring machine 1 of the above embodiment is shown in the conceptual diagram of FIG. As shown, the workpiece installation plate 48 of the workpiece support mechanism 40, which is a form of the support means of the configuration requirement (1), supports a part of the lower side of the peripheral surface of the workpiece W as the first portion. In addition, the rubber portion 86 of the work drive mechanism 70 which is one form of the rotating means of the configuration requirement (2) is driven by the drive portion 72 while contacting a part of the upper side of the peripheral surface of the work W as the second part. The workpiece W is rotated by moving in a direction orthogonal to the rotation axis of the workpiece W. Further, the detector 30 which is one form of the detection means of the configuration requirement (3) is arranged and fixed by the detector support mechanism 10 at a position facing the third portion which is a part of the lower side of the peripheral surface of the workpiece W, The surface roughness in the circumferential direction of the peripheral surface of the workpiece W is detected.

  On the other hand, the surface roughness measuring machine according to the present invention can change the first part, the second part, and the third part to arbitrary positions with respect to the workpiece W. For example, FIG. As shown in the conceptual diagram, the positions of the workpiece installation plate 48, the rubber portion 86, and the detector 30 are arranged at positions rotated by 180 degrees around the rotation axis of the workpiece W, whereby the first part and the second part , And the third part can be set to a position rotated 180 degrees around the rotation axis of the workpiece W. Similarly, the first part, the second part, and the third part may be arranged around the rotation axis of the work W at an arbitrary angle other than 180 degrees.

  Moreover, as shown in the conceptual diagram of FIG. 11, the positions of the second part and the third part can be exchanged by exchanging the positions of the rubber part 86 and the detector 30. In this case, the load from the workpiece W can be dispersed and supported by the rubber portion 86 and the workpiece installation plate 48. The ratio can be changed by adjusting the pressure applied to the workpiece W by the rubber portion 86 (adjustment of pressurization by the pressurizing unit 80). Therefore, even when the weight of the workpiece W is large and it is difficult to rotate the workpiece W against the frictional force between the workpiece W and the workpiece setting plate 48, the ratio of the load on the rubber portion 86 is increased. The workpiece W can be rotated.

  Further, as described above, the second part and the third part in the positional relationship between the measurement point and the support point are positions 180 degrees opposite to each other in the circumferential direction of the workpiece W as in the above embodiment. Although it is desirable because there is little noise in the measurement signal due to the vibration of the workpiece W, the detector 30 may be arranged at a position different from that as shown by a broken line in FIG. Furthermore, the detector 30 may be a non-contact type using a laser or the like instead of a stylus type that makes the tip of the measuring element 34 contact the work W as in the above embodiment. Even in such a case, the measurement position for measuring the surface roughness by the detector 30 may be arranged and fixed at the third site.

  W: Workpiece, 1 ... Surface roughness measuring device, 2 ... Measuring unit, 3 ... Data processing unit, 4 ... Base, 4A ... Straight groove, 5 ... Column, 6 ... Controller, 10 ... Detector support mechanism, 12 ... No. 1 fixed plate, 14 ... second fixed plate, 16 ... XYZ stage, 18B ... Y stage, 20B ... X stage, 22B ... Z stage, 24 ... detector holder, 30 ... detector, 32 ... detector body, 34 ... Measuring element 36 ... Stylus 40 ... Work support mechanism 42 ... Leg part 44, 78 ... Support part 44A ... Through hole 46 ... Work installation base 48 ... Work installation plate 48A ... Taper hole 50 DESCRIPTION OF SYMBOLS 98 ... Screw with knob, 52 ... Positioning pin, 70 ... Work drive mechanism, 72 ... Drive part, 74 ... Arm, 76 ... Pressure unit, 78A ... Tip part, 78B ... Base end part, 80 ... Pressure part, 82 ... Spring part, 84 ... Tip support part, 86 ... Go Parts, 88 ... indicator needle, 90 ... pressure alignment mark, 92 ... stopper, 94 ... arm member, 96 ... stopper

Claims (7)

A support means for supporting a first part which is a part of a peripheral surface of an object to be measured including a sphere or a rotating body;
Rotating means for rotating the object to be measured by moving in a direction orthogonal to the rotation axis of the object to be measured while being in contact with a second part which is another part of the peripheral surface of the object to be measured;
A detecting means which is arranged and fixed at a position facing a third part which is still another part of the peripheral surface of the object to be measured, and detects the surface roughness in the circumferential direction of the peripheral surface of the object to be measured;
A surface roughness measuring machine.   The rotating means is a flat surface parallel to the rotation axis and is in contact with the object to be measured, and driving means for moving the contact surface straight in a direction along the flat surface. The surface roughness measuring machine according to claim 1.   The surface roughness measuring machine according to claim 1 or 2, wherein the third part is a position that is 180 degrees opposite to the second part in the circumferential direction.   The surface roughness measuring machine according to claim 1, 2 or 3, wherein the detecting means is a contact type detecting means having a measuring element whose tip is in contact with the third part.   5. The surface roughness measurement according to claim 1, wherein the rotating unit includes a pressurizing unit that pressurizes the object to be measured through a contact surface that contacts the object to be measured. Machine.   The said support means is provided with the plate-shaped body which has a taper-shaped hole into which the range of a part of peripheral surface of this spherical body enters, when the said to-be-measured object is a spherical body. The surface roughness measuring machine described.   The said support means is equipped with the plate-shaped body which has a taper-shaped groove | channel where the one part range along the said rotating shaft of the surrounding surface of this rotary body enters, when the said to-be-measured object is a rotary body. The surface roughness measuring machine according to any one of the above.

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