JP4529664B2 - Tool shape measuring apparatus and method - Google Patents

Description

The present invention relates to a measuring apparatus for inspecting whether or not a cutting edge shape of a tool after re-polishing is accurate when, for example, a drill which is a rod-shaped tool is re-polished and used.

  The drill or end mill used in cutting or drilling is worn while the cutting edge is worn by the tool grinder because the cutting edge at the tip contacting the workpiece (workpiece) is worn as the usage time increases. . This polishing operation is called re-polishing, but the shape of the cutting edge after re-polishing, especially the shape of the cutting edge, has a great influence on machining accuracy and tool life. For example, a drill usually has a plurality of cutting edges at its tip, but if there is a difference in their shape, machining is performed with only a specific cutting edge, or the deflection of the drill during machining is abnormal. This causes a problem that becomes larger.

  Therefore, after re-polishing, an accurate polishing is performed and an inspection is performed as to whether or not each portion has a predetermined shape. This inspection is performed at a work site such as a factory, and in a simple case, it is manually inspected using a V block and a dial gauge. In the inspection using the V block, a polished drill is placed in the V groove of the V block, and a dial gauge probe is applied to one of the plurality of cutting edges as shown in FIG. This is the reference position. Next, the drill is rotated in the V groove, and the positions of the other cutting edges are measured in the same manner to obtain the difference from the reference position. This operation is performed at several points necessary for specifying the shape of the cutting edge, the difference in the shape of each cutting edge is detected, and the pass / fail of re-polishing is determined.

  In a device that inspects a tool whose tip of the cutting edge forms an arc, such as a ball end mill, the tool is fixed to the rotating shaft by a chuck, and the dial gauge is installed so that it can be rotated according to the shape of the arc. There is something. While turning the dial gauge, measure the position of several points on the arc of one of the cutting edges, rotate the tool fixed to the rotating shaft, measure the position of the other cutting edges in the same way, Is detected (see FIG. 7B).

  Further, there is an apparatus disclosed in Japanese Patent Laid-Open No. 6-137842 as an automated tool for measuring and inspecting such a tool shape. This apparatus combines a tool microscope and a television camera to measure the shape of the cutting edge of a tool such as a ball end mill. FIG. 8 shows an outline of the apparatus.

  A tool 30 such as a ball end mill to be inspected is attached to a chuck 31 and is rotatable about an axis A. The chuck 31 is supported by an angle indexing device 32. The angle indexing device 32 is installed on a table 33 that is movable in the X-axis and Y-axis directions. The direction can be moved by a feed screw 36 and a motor 37. A tool microscope 38 and a television camera 39 having an axis P as an optical axis are provided above the tool 30, and the television camera 39 is connected to the image processing apparatus.

When measuring the shape of the tool, the focus of the optical microscope 38 is fixed to the position of the axis A, then the table 33 is moved, and the axis P, which is the optical axis of the tool microscope, is changed to a tool with a cutting edge. Match with the measurement point on the contour of the tip. Thereafter, the position of the cutting edge at the measurement point is detected by an image processing device connected to the television camera 39, and the tool 30 is rotated around the axis A so as to match the focal position of the tool microscope 38, thereby determining the angular position. . Such measurement is performed at a plurality of measurement points on the contour of the tool tip, and the dimensions, shape, and the like of the cutting edge of the tool 30 are measured using the obtained X-axis, Y-axis, and angular position data. Thus, the inspection of the tool 30 or the pass / fail determination can be performed.
JP-A-6-137842

As described above, there are several methods for inspecting a tool such as a drill. Of these, the method using the V block and dial gauge is basically a manual operation performed by the operator and is a simple method. However, it requires a long period of work and is necessary for accurate inspection. It shall be subject to a skilled person.

  In the apparatus disclosed in Patent Document 1, although automatic measurement is possible, a tool microscope and an image processing apparatus must be provided, and an inspection apparatus becomes very expensive, and at the present time, measurement is possible. There is a limit to the size of the tool. Furthermore, in the inspection after tool re-polishing at the work site, it is often sufficient as a pass / fail judgment if it is inspected whether the difference in dimensions, angles, etc. of the plurality of cutting edges is within an allowable range, There is an aspect that does not require a high-quality device capable of precise measurement. An object of the present invention is to inspect the shape of a cutting edge portion of a tool after re-polishing or the like with a relatively simple device with necessary and sufficient accuracy.

In view of the above problems, the present invention aims to measure the shape of a cutting edge of a drill, which is a rod-shaped tool provided with a linear cutting edge, with a simple device without any variation in accuracy by an operator. And That is, the present invention
"A tool shape measuring apparatus for measuring the shape of the cutting edge of the drill with a straight cutting edge, rectilinear and the tool holding device for rotating and holding the drill, the upper rotating shaft parallel to the plane of the drill In a tool shape measuring device having a sliding table that slides on
A swivel table supported on the slide table and capable of swiveling with respect to the slide table, and a support base that slides along a straight line perpendicular to the radial direction of the swivel axis of the swivel table, are provided on the support base. A laser displacement meter is mounted facing the cutting edge, and the laser displacement meter is slid along a straight line perpendicular to the radial direction of the turning shaft of the turning table, and the laser displacement meter and the cutting edge Measure distance at multiple points. ''
This is a tool shape measuring device characterized by this.

According to a second aspect of the present invention, the laser displacement meter is connected to a data processing device that scans the distance between the tip of the drill and the laser displacement meter over a certain width to detect the position of the cutting edge. can do.

The present invention can be implemented as an invention of a method for measuring the shape of a cutting blade of a drill. In this case, as described in claim 3,
"A tool shape measuring method for measuring the shape of a cutting edge of a drill having a linear cutting edge,
Attaching the drill to a tool holding device for holding and rotating the drill,
A laser displacement meter is installed on a turning table that rotates on a plane parallel to the rotation axis of the drill so as to face the tip of the drill, and the laser displacement meter is linearly parallel to the cutting edge of the drill. Slide and measure the distance between the laser displacement meter and the cutting edge of the drill at multiple points. "
This is a tool shape measuring method characterized by this.

In the present invention, when measuring the shape of the cutting edge of the drill is a rod-like tool, with to hold the drill rotation to the tool holding device, placing the support base fitted with a laser displacement meter on a pivotable turntable The laser displacement meter installed opposite the linear cutting edge at the tip of the drill is linearly moved on the swivel table along a straight line perpendicular to the radial direction of the swivel axis of the swivel table. . The distance between the laser displacement meter and the measuring point of the cutting edge facing it is measured at multiple points to determine the shape of the cutting edge of the drill , and the same shape measurement is performed for the multiple cutting edges of the drill. Then, the pass / fail of the tool polishing is determined. Since only the distance is measured, the apparatus is simple, and it is possible to carry out an inspection at a manufacturing / processing site such as a factory without a skilled worker. The laser displacement meter is capable of precise measurement and can measure the shape with sufficient accuracy.

In the invention of claim 2, the position of the cutting edge is detected by scanning the distance between the tip of the drill and the laser displacement meter over a certain width. That is, since the point where the distance is the shortest by scanning in the direction perpendicular to the cutting edge is determined as the cutting edge position, the position can be accurately determined.

The invention of claim 3 has the shape measuring method of the cutting edge of the drill is a rod-like tool. In the drill, the cutting edge is almost straight in plan view, and when the laser displacement meter installed on the swivel table is moved parallel to this straight line, the distance to the cutting edge hardly changes and stable measurement can be performed. The In the invention of claim 3, it is clear that also achievable invention the same effect as in claim 1 above.

  Hereinafter, a tool shape measuring apparatus and method according to the present invention will be described with reference to the drawings. FIG. 1 is a plan view schematically showing a tool shape measuring apparatus according to the present invention, in which a motor for driving a table and the like, and a data processing apparatus for processing measurement data are also shown. FIG. 2 is a schematic front view of the apparatus in a state where the laser displacement meter is placed so as to face the bar-shaped tool, and FIG. 3 is a view showing a drive device of the turning table.

  On the base 1 of the tool shape measuring device, a tool holding device 4 that includes a chuck 3 for fixing the bar-shaped tool 2 and an indexing mechanism for a rotational position and that rotates the bar-shaped tool to be inspected is placed. The rod-shaped tool 2 in FIG. 1 is a drill, and has a linear cutting edge 5 in a plan view at a tip portion thereof, and can be rotated by a stepping motor 7 with a shaft 6 as a rotation axis. Instead of using the stepping motor 7, it may be rotated manually.

  A rail 8 is formed on the base 1 in parallel with the rotary shaft 6, and a sliding table 9 is placed on the rail 8. The sliding table 9 is slid by the stepping motor 23 in parallel with the rotary shaft 6 along the rail 8 using, for example, a feed screw mechanism. As shown in FIG. 3, the sliding table 9 is basically U-shaped in cross section when viewed from the direction of the rotating shaft 6 and has a hollow central portion. The through hole 10 is opened.

  A turning table 11 is placed on the sliding table 9. As shown in FIGS. 2 and 3, a columnar turning shaft 12 is integrally formed at the lower portion of the turning table 11 and is fitted into the through hole 10 of the sliding table 9. A worm gear 13 is fixed below the turning shaft 12, and the worm gear 13 meshes with a worm 14 disposed in a hollow portion of the sliding table 9. The worm 14 is rotationally driven by a stepping motor 15 attached to the side surface of the sliding table 9. Therefore, the turning table 11 can turn around an axis perpendicular to the rotating shaft 6 on a plane parallel to the rotating shaft 6.

A support base 16 that slides linearly is placed on the upper surface of the turntable 11, and a laser displacement meter 17 is fixed to the support base 16. The laser displacement meter 17 is installed at the same height as the rotary shaft 6 so as to face the cutting edge of the drill 2 which is a rod-shaped tool. The support 16 is guided by the rail on the upper surface of the turning table 11 by the stepping motor 18 and can slide linearly along a straight line perpendicular to the radial direction of the turning shaft of the turning table 11 . That is, the support base 16 is movable in parallel to the linear cutting edge 5 of the drill 2.
The laser displacement meter 17 on the support base 16 irradiates the tip of the drill 2 which is a rod-shaped tool with laser, and measures the distance to the tip using the reflected light. The measurement data is input to the data processing device 19. Further, the rotation amount of each stepping motor is controlled by the control device 20, and those data are also input to the data processing device 19.

Here, measurement method of using a tool shape measuring apparatus of the present invention will be described with reference also to FIG. 4 to FIG. First, after attaching the drill 2 which is a rod-shaped tool to be inspected to the tool holding device 4, the slide table 9 is slid on the base 1 according to the length of the drill, and the laser displacement meter 17 is moved to the tip of the drill. Is brought close to the cutting edge 5. FIG. 4A is a view of the tip of the drill as viewed from the axial direction, but the cutting edge 5 of the drill is usually a straight line. The tool holding device 4 rotates and positions the drill so that the straight line of the cutting edge 5 is positioned on the horizontal plane, and the turning table 11 is further adjusted so that the rail on the turning table 11 is parallel to the cutting edge 5 in the plan view. Turn.

  In this state, laser is irradiated from the laser displacement meter 17, and the distance between the laser displacement meter 17 and the surface of the tip of the drill is measured. As shown in FIG. 4 (a), the measurement is performed by moving the support 16 of the laser displacement meter 17 by the stepping motor 18 to the measurement points 1, 2 to n, and moving the laser in the direction perpendicular to the cutting edge. As shown in FIG. As a result, the data shown in FIG. 4B is obtained for the measurement points 1, 2 to n. Since the position of the cutting edge of the drill at each measurement point is the point with the shortest distance, the peak value of the arrow in FIG. 4B corresponds to the position of the cutting edge. The detection of the peak value is executed by the data processing device 19, and the distance of the cutting edge at each measurement point is obtained. Moreover, the distance at the point between each measurement point can be calculated | required by interpolating the data of each measurement point with the data processor 19, and the continuous cutting-blade shape is determined.

  When the measurement is completed for one cutting edge of the drill, the stepping motor 7 is driven to rotate the drill 180 degrees, and the same measurement is performed for the other cutting edge. At the time of re-polishing, as shown in FIG. 5A, when both the cutting edges are not accurately polished, the angles of the cutting edges become asymmetric, and the shapes of both cutting edges are as shown in FIG. ) As shown in the measurement results. In this way, by comparing the shape of both cutting edges after re-polishing, it is possible to inspect the re-polishing operation of the drill, and it is easy to determine whether or not it is acceptable even at a work site such as a factory. It will be possible.

As a reference example, FIG. 6 shows an inspection method for a ball end mill having an arcuate cutting edge using an inspection apparatus similar to the present invention . Since the laser displacement meter 17 performs measurement using the reflected light of the laser, the measurement error increases when the angle formed by the tangent to the cutting edge of the measurement point and the laser beam is large. In order to prevent this, in the inspection of the ball end mill, the turning table 11 is positioned so that the rail on the turning table 11 on which the support base 16 slides forms an angle of 45 degrees with respect to the rotary shaft 6 of the tool.

  At this position, the laser displacement meter 17 slides in parallel with the tangent at the center position of one of the cutting edges, and thus both ends of the measurement portion, that is, the intersection 21 between the rotating shaft 6 and the cutting edge and the outer peripheral edge of the cutting edge. 22, the angle formed by the axis of the displacement meter 17 and the tangent line of the cutting edge becomes equal. Therefore, the laser displacement meter 17 can averagely receive the reflected light of the irradiated laser, and avoid an increase in measurement error due to an increase in the angle formed by the tangent line between the laser beam and the cutting edge measurement point. it can. In some cases, the amount of rotation of the turntable 11 relative to the rotating shaft 6 can be changed stepwise so that the laser beam is irradiated as close to a right angle as possible at the cutting edge of each measurement point. After the measurement of one cutting edge is completed, the pass / fail judgment can be made by rotating the ball end mill 180 degrees and measuring and comparing the shape of the other cutting edge, as in the case of the above-described drill.

As described in detail above, the present invention aims to measure the shape of a linear cutting edge in a drill with a simple device without variation in accuracy by an operator. Hold and rotate the drill , and slide the support base with the laser displacement meter on the swivelable turntable so that the laser displacement meter installed facing the cutting edge at the tip of the drill moves linearly. It is something to be made. Although a stepping motor is used here to drive the support base and the table, it is obvious that other drive mechanisms such as an actuator having a hydraulic cylinder can be employed. Further, in order to rotate the turning table, for example, a well-known link mechanism that changes the reciprocating motion into a rotational motion can be used instead of the worm mechanism.

It is a schematic plan view of the tool shape measuring apparatus of this invention. It is a schematic front view of the tool shape measuring apparatus of this invention. It is a figure which shows the drive device of the turning table of this invention. It is explanatory drawing which shows the measuring method of the drill cutting edge based on this invention. It is explanatory drawing which shows the pass / fail determination method of the drill based on this invention. It is explanatory drawing which shows the pass / fail determination method of a ball end mill as a reference example . It is explanatory drawing of the conventional tool shape measuring method. It is a perspective view of the conventional tool shape measuring apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Base 2 Bar-shaped tool 4 Tool holding device 5 Cutting blade 9 Sliding table 11 Turning table 13 Worm gear 14 Worm 16 Support stand 17 Laser displacement meter 19 Data processing device

Claims (3)

A tool shape measuring device for measuring the shape of a cutting edge (5) of a drill (2) having a linear cutting edge, the tool holding device (4) for holding and rotating the drill (2), and the drill In a tool shape measuring apparatus having a sliding table (9) that slides linearly on a plane parallel to the rotational axis (6) of (2),
A turning table (11) supported on the sliding table (9) and capable of turning with respect to the sliding table (9), and a support that slides along a straight line perpendicular to the radial direction of the turning axis of the turning table. And a laser displacement meter (17) is attached to the support table (16) so as to face the cutting edge (5), and the laser displacement meter (17) is attached to the turning shaft of the turning table. The tool shape measuring apparatus is characterized in that the distance between the laser displacement meter (17) and the cutting edge (5) is measured at a plurality of points by sliding along a straight line orthogonal to the radial direction. The laser displacement meter (17) scans the distance between the tip of the drill (2) and the laser displacement meter (17) over a certain width to detect the position of the cutting edge (5). The tool shape measuring device according to claim 1, to which a processing device (19) is connected. A tool shape measuring method for measuring the shape of a cutting edge (5) of a drill (2) having a linear cutting edge ,
The drill (2) is attached to a tool holding device (4) for holding and rotating the drill (2),
A laser displacement meter (17) is installed on a turning table (11) that turns on a plane parallel to the rotation axis (6) of the drill (2) so as to face the tip of the drill (2). A laser displacement meter (17) is linearly slid parallel to the cutting edge (5) of the drill (2), and the laser displacement meter (17) and the cutting edge (5) of the drill (2) A tool shape measuring method comprising measuring a distance at a plurality of points.

Images