JP2004142067A - Nc multiple-spindle grinding machine and grinding method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an NC multiple-spindle grinding machine with increased rigidity of a W spindle. <P>SOLUTION: The NC multiple-spindle grinding machine to grind a work by the relative movement between a grinding tool rotated around a predetermined axis and the work comprises: a bed 12; a column 14 which is straight-movable in two horizontal axial directions orthogonal to each other on an upper portion of the bed 12; a grinding wheel head 18 which is straight-movable on the column 14 in the vertical direction to rotatably support a grinding wheel shaft 24 with a grinding tool 30 fitted thereto; a turntable 58 which is on the upper portion of the bed 12 rotatably around the vertical axis; and a work spindle head 68 which is disposed on the turntable 58 to rotatably support a work spindle 70 to fix a work 76 around the horizontal axis. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an NC multi-axis grinding machine and a grinding method, and particularly to an NC multi-axis grinding machine which measures a tool such as a ball end mill on a machine with high accuracy and grinds the workpiece based on the measurement result. It relates to a board and a grinding method.
[0002]
[Prior art]
In an NC grinding machine having five or more axes, generally, a grindstone head that rotationally supports a grindstone shaft on which a rotating grindstone is mounted and a spindle head that rotationally supports a work linearly move in three orthogonal (XYZ axis) directions. The spindle head is rotatable about a vertical axis (W axis). In the prior art, the W axis is disposed on the XY movement axis. Such an NC multi-axis grinding machine is used for grinding a workpiece having a complicated shape such as a tool having a twisted blade.
[0003]
By the way, it is very difficult to measure the tip of a cutting edge of a tool having a torsion blade such as a ball end mill because of its complicated shape, and various measuring methods and measuring devices have been conventionally proposed.
[0004]
[Problems to be solved by the invention]
In the conventional NC multi-axis grinding machine, as described above, the W axis is disposed on the XY moving axis, and there is a problem that the rigidity of the W axis cannot be increased. In the measurement of a tool having a twisted blade such as a ball end mill, it is very difficult to eliminate measurement errors due to the complexity of the tool shape. In particular, the lack of a clear standard on which part of the tool the tip of the cutting edge should be measured makes it difficult to solve the problem.
[0005]
An object of the present invention is to solve such a problem of the related art, and an object of the present invention is to provide an NC multi-axis grinding machine with increased rigidity of a W-axis.
Another object of the present invention is to provide a tool which is a workpiece ground by such an NC multi-axis grinding machine, in particular, a method and an apparatus for measuring the shape of a ball end mill for precisely measuring the shape of the tip of a ball end mill. I have.
Another object of the present invention is to provide a ball end mill grinding method and apparatus for grinding a ball end mill based on the measurement results obtained by the measurement method.
[0006]
[Means for Solving the Problems]
The present invention according to claim 1 is an NC multi-axis grinding machine that grinds the workpiece by a relative movement between the grinding tool and the workpiece rotating around a predetermined axis,
A bed as a base,
A column provided on the bed so as to be linearly movable in two horizontal axis directions orthogonal to each other;
A linear moving linearly in the vertical direction on the column, a grindstone head rotatably supporting a grindstone shaft for mounting the grinding tool,
A swivel provided on the bed so as to be rotatable around a vertical axis,
A work spindle head provided on the swivel table and supporting a work spindle for fixing the work so as to be rotatable around a horizontal axis;
An NC multi-axis grinding machine characterized by comprising:
[0007]
The present invention according to claim 3 is a method for grinding a ball end mill,
Determine the cutting edge tip of the ball end mill to be measured at every predetermined angle around the center of the ball end mill tip ball portion, and determine the center of the ball end mill tip ball portion and the determined cutting edge tip to be measured. A sensor for reading the coordinate position is moved from the radial outside to the center of the tip sphere of the ball end mill along the connecting line, and the center of the tip sphere of the ball end mill and the tip of the cutting edge are moved. The distance was measured at each predetermined angle around the center of the ball end mill tip ball portion, and the grinding amount was obtained at each of the predetermined angles around the center of the ball end mill tip ball portion from the measured value, so that the grinding was performed. The gist is a method of grinding a ball end mill.
[0008]
The present invention according to claim 4 is a method for grinding a ball end mill,
(A) a step of supporting the ball end mill rotatably about a longitudinal central axis and about an axis perpendicular to the central axis by work supporting means;
(B) rotating the ball end mill around the center axis to adjust the tip of the ball end mill to the height of the center axis;
(C) moving a sensor for reading a coordinate position along a straight line connecting the center of the tip sphere of the ball end mill and the tip of the cutting edge to move the sensor between the center of the tip sphere of the ball end mill and the tip of the cutting edge; Measuring the distance;
(D) rotating the ball end mill by a predetermined angle about an axis passing through the center of the ball portion of the ball end mill and perpendicularly intersecting the longitudinal center axis of the ball end mill;
The steps (b), (c) and (d) are repeated to measure the shape of the ball end mill tip at every predetermined angle around the center of the tip ball of the ball end mill;
The gist of the present invention is a ball end mill grinding method in which a grinding amount is obtained for each predetermined angle around the center of the ball end mill tip ball portion from the obtained shape of the tip end portion of the ball end mill, and the grinding is performed.
[0009]
The present invention according to claim 5, a ball end mill grinding apparatus for grinding the ball end mill by a relative movement between a grinding tool rotating around a predetermined axis and a ball end mill,
A bed as a base,
A column provided on the bed so as to be linearly movable in two horizontal axis directions orthogonal to each other;
A linear moving linearly in the vertical direction on the column, a grindstone head rotatably supporting a grindstone shaft for mounting the grinding tool,
A swivel provided on the bed so as to be rotatable around a vertical axis,
A work spindle head provided on the swivel table and supporting a work spindle for fixing the ball end mill rotatably about a horizontal axis;
A sensor for reading the coordinate position attached to the grinding head,
The turning table is rotated around a vertical axis, and the cutting edge of the ball end mill to be measured at predetermined angles around the center of the ball end mill is determined around the center of the ball end mill tip, and the center of the ball end mill tip ball is determined. Move the sensor from the radial outside to the center of the ball end mill tip along a straight line connecting the determined cutting edge tip to be measured and the center of the ball end mill tip ball. The distance from the tip of the cutting edge is measured at predetermined angles around the center of the ball end mill tip of the ball end mill, and from the measured value, the amount of grinding at the predetermined angle around the center of the ball end mill tip ball portion. The gist of the present invention is to provide a ball end mill grinding device for grinding.
[0010]
The present invention according to claim 6 is a ball end mill grinding apparatus for grinding the ball end mill by a relative movement between a grinding tool and a ball end mill rotating around a predetermined axis,
A bed as a base,
A column provided on the bed so as to be linearly movable in two horizontal axis directions orthogonal to each other;
A linear moving linearly in the vertical direction on the column, a grindstone head rotatably supporting a grindstone shaft for mounting the grinding tool,
A swivel provided on the bed so as to be rotatable around a vertical axis,
A work spindle head provided on the swivel table and supporting a work spindle for fixing the ball end mill rotatably about a horizontal axis;
A sensor for reading the coordinate position attached to the grinding head,
(A) supporting the ball end mill on the work spindle;
(B) rotating the work spindle to rotate the ball end mill around its longitudinal center axis to adjust the tip of the blade end of the ball end mill to the height of the center axis;
(C) moving the sensor along a straight line connecting the center of the ball tip end of the ball end mill and the tip of the cutting edge to measure the distance between the center of the ball tip end of the ball end mill and the tip of the cutting edge; Process and
(D) rotating the swivel base to rotate the ball end mill by a predetermined angle around an axis passing through the center of the ball portion of the ball end mill and perpendicular to the longitudinal center axis of the ball end mill;
The steps (b), (c) and (d) are repeated to measure the shape of the tip of the ball end mill at every predetermined angle around the center of the tip of the ball end mill;
The gist of the ball end mill grinding device is such that a grinding amount is obtained at each predetermined angle around the center of the ball end mill tip ball portion from the determined shape of the tip end portion of the ball end mill, and the grinding is performed.
[0011]
The present invention according to claim 8 is a method for measuring the shape of a ball end mill,
Determine the cutting edge tip of the ball end mill to be measured at every predetermined angle around the center of the ball end mill tip ball portion, and determine the center of the ball end mill tip ball portion and the determined cutting edge tip to be measured. A sensor for reading the coordinate position is moved from the radial outside to the center of the tip sphere of the ball end mill along the connecting line, and the center of the tip sphere of the ball end mill and the tip of the cutting edge are moved. The gist is a method of measuring the shape of a ball end mill, wherein the distance is measured at predetermined angles around the center of the ball portion of the ball end mill.
[0012]
The present invention according to claim 9 is a method for measuring the shape of a ball end mill,
(A) supporting the ball end mill rotatably about a longitudinal central axis;
(B) rotating the ball end mill around the center axis to adjust the tip of the ball end mill to the height of the center axis;
(C) moving a sensor for reading a coordinate position along a straight line connecting the center of the tip sphere of the ball end mill and the tip of the cutting edge to move the sensor between the center of the tip sphere of the ball end mill and the tip of the cutting edge; Measuring the distance;
The gist is a method for measuring the shape of a ball end mill comprising:
[0013]
The present invention according to claim 12 is a ball end mill shape measuring device,
Work supporting means for supporting the ball end mill rotatably about a longitudinal central axis and an axis perpendicular to the central axis,
Moving means for relatively linearly moving a coordinate position reading sensor relative to the ball end mill along three orthogonal axes,
The ball end mill is rotated around the center axis to adjust the tip of the cutting edge of the ball end mill to the height of the center axis, and the sensor is moved along a straight line connecting the center of the tip sphere of the ball end mill and the tip of the cutting edge. The gist of the ball end mill shape measuring apparatus is such that the distance between the center of the ball portion of the ball end mill and the tip of the cutting edge is measured by moving the ball end mill.
[0014]
The present invention according to claim 18 is a method for measuring the shape of a rotary tool,
(A) supporting the tool rotatably about a longitudinal central axis;
(B) rotating the tool around the center axis to adjust the cutting edge of the tool to the height of the center axis;
(C) measuring the distance between the cutting edge of the tool and the central axis;
The gist is a method for measuring the shape of a rotary tool comprising:
[0015]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.
First, the NC multi-axis grinding machine 10 is a 7-axis NC grinding machine, which is fixed to the floor of a factory and serves as a base for the NC multi-axis grinding machine 10, and is erected on the upper surface of the bed 12. And a grinding wheel head feed base 16 attached to a side surface of the column 14 so as to be vertically movable (Z-axis direction). A grindstone head 18 and a dress saddle 20 are mounted on the grindstone head slide 16, and a servomotor 22 as a Z-axis feed motor for moving the grindstone head slide 16 in the Z-axis direction is mounted on the top of the column 14. Have been. The grindstone head 18 is also attached to the grindstone head feed base 16 so as to be rotatable about an axis B perpendicular to the Z axis (perpendicular to the plane of FIG. 1).
[0016]
The grindstone head 18 supports a grindstone shaft 24 rotatably around a central axis O of the grindstone head 18 via bearings 18a and 18b, and incorporates a built-in motor 26 for driving the grindstone shaft 24 to rotate. A rotating grindstone 30 is attached to the tip of the grindstone shaft 24 via an HSK type tool holder 28. A load cell 19 for measuring a thrust force acting on the grindstone shaft 24 is provided at a rear end of the grindstone shaft 24. Further, a touch sensor 88 for reading a coordinate position connected to the NC device 84 is preferably provided on the outer peripheral surface of the grinding head 18, in particular, on a front flange so that its measuring probe is vertically suspended from the grinding head 18. Installed. In this case, the grinding head 18, especially its housing, acts as a sensor support.
[0017]
The dresser saddle 20 is attached to the grindstone head feed bar 16 or the grindstone head 18 so as to be able to reciprocate in a direction parallel to the axis O. A dresser feed bar 32 is provided at the tip of the dresser saddle 20 with respect to the axis O. It is mounted so that it can reciprocate vertically in a vertical direction. More specifically, the dresser saddle 20 is reciprocally driven in a direction parallel to the axis O by the servomotor 38 and the feed screw 40, and the dresser feed base 32 is moved in a direction perpendicular to the axis O by the servomotor 42 and the feed screw 44. Is reciprocated. A dresser tool 36, which is driven to rotate by a hydraulic motor 34, is attached to the tip of the dresser feed table 32.
[0018]
A pair of X-axis guide rails 56 are provided on the upper surface of the bed 12 and extend in the horizontal direction along the X-axis, and the table 46 is movably mounted along the X-axis guide rails 56. ing. The table 46 is reciprocated by an X-axis feed screw (not shown) and a servomotor 54 as an X-axis feed motor. A Y-axis feed screw 50 extends on the upper surface of the table 46 in a direction perpendicular to the X-axis and the Z-axis. The rear end of the Y-axis feed screw 50 is connected to a servomotor 48 as a Y-axis feed motor. Are linked. Further, a nut 14 a that engages with the Y-axis feed screw 50 is connected to the lower end of the column 14. Thereby, the column 14 is reciprocated along the X axis and the Y axis.
[0019]
A swivel 58 is mounted on the bed 12 so as to be swivelable about an axis (W axis) extending in the vertical direction. More specifically, the turntable 58 has a turntable shaft portion 58a extending vertically downward at one end thereof, and the turntable shaft portion 58a preferably has a boss portion projecting upward from the upper surface of the bed 12. It is rotatably supported by bearings 78a and 78b arranged on 12a. The lower end of the turntable shaft portion 58a is connected to an output shaft of a servomotor 66 as a W-axis turn motor disposed in the bed 12, and the turntable 58 is driven to rotate about a vertical W-axis. Is done.
[0020]
According to the present embodiment, since the W axis is fixed to the bed 12, the rigidity of the W axis can be increased. In particular, by providing the boss 12a protruding upward from the upper surface of the bed 12 and rotatably supporting the turntable shaft 58a of the turntable 58 with the boss 12a, the turntable shaft 58a is formed. According to this embodiment, the rigidity of the W-axis can be significantly increased as compared with the related art in which the swivel table is arranged on the X and Y movement axes. Therefore, according to the present embodiment, it is possible to increase the positioning accuracy around the W axis when grinding the tip of the work 76. This is particularly advantageous when the workpiece 76 is a ball end mill and the R shape at the tip of the ball end mill is measured and ground with high accuracy.
[0021]
A work feed table 60 is attached to the turntable 58 so as to be reciprocable in a horizontal axis (U-axis) direction. A servo motor 62 serving as a U-axis feed motor and a U-axis feed screw are attached to the turntable 58. 64 is reciprocated. The U-axis feed motor may not be provided, and the U-axis may be manually fed. A work spindle 68 is attached to the work feed base 60, and the work spindle 68 supports the work spindle 70 rotatably about an axis A parallel to the U axis. The work spindle 70 is rotationally driven by a servo motor 72 as a spindle drive motor. A work 76 is attached to the tip of the work spindle 70 via a work holder 74. In the present embodiment, the workpiece 76 is a ball end mill to be ground by the NC multi-axis grinding machine 10. A power supply brush 80 is provided at the rear end of the work spindle 70, and a predetermined voltage is applied between the power supply brush 70 and the touch sensor 88. When the work 76 and the touch sensor 88 come into contact with each other, the work 76 and the touch sensor 88 are short-circuited, and the NC device 84 uses the signal as a skip signal to measure the outer shape of the work 76 from the coordinates of each axis at that time. It becomes possible.
[0022]
Prior to grinding, a work 76, preferably a ball end mill, is attached to the tip of the work spindle 70. Next, the grindstone shaft 24 and the work spindle 70 are rotated by the built-in motor 26 and the servomotor 72, and the work feed base 60 is moved in the U-axis direction by the servomotor 62 to press the work 76 against the rotating grindstone 30. In the meantime, the tip of the work 76 is ground by rotating the turntable 58 about the W axis or rotating the grindstone head 18 around the B axis. The shape and dimensions of the tip of the workpiece 76 during the grinding can be obtained by calculation by reading the coordinates of each axis from the NC device 84. However, in the present embodiment, as will be described later, the touch sensor 88 is brought into contact with the work 76, the short-circuit current at that time is captured as a skip signal, and the coordinates of each axis are read from the NC device 84 to form the tip shape of the work 76. Can be obtained accurately. The touch sensor is not limited to the short-circuit type, but may be another type. Further, a displacement detection type sensor may be used instead of the touch sensor.
[0023]
At this time, at the start of the grinding process, as shown in FIG. 1, with the work 76 facing the rotary grindstone 30, the work feed base 60 is moved in the Y-axis direction to bring the work 76 close to the rotary grindstone 30. . When the workpiece 76 comes into contact with the rotating grindstone 30, sound or vibration generated by the contact between the two is detected by the acoustic sensor 81. The acoustic sensor 81 can be formed by a microphone composed of a voice coil and a permanent magnet, or a microphone composed of a piezoelectric element, and can detect sound or vibration generated by the contact between the work 76 and the rotating grindstone 30. Any sensor can be used.
[0024]
A very large frictional force acts on the grinding surface of the rotary grindstone 30 that contacts the work 76 and grinds the work 76, and wears. Further, while the sharpness of the grinding surface of the rotary grindstone 30 is maintained, the wear is also caused by dressing for maintaining the shape of the grinding surface flat. As in the present embodiment, the contact between the workpiece 76 and the rotating grindstone 30 is detected by the acoustic sensor 81, and this is sent to the NC device 84 as a skip signal, and the coordinates of each axis at that time are read, whereby the rotating grindstone 30 is read. It is possible to calibrate the retreat position of the ground surface.
[0025]
With the work spindle 70 and the grindstone shaft 24 being rotated, the tip of the work 76 is pressed against the grinding surface of the rotating grindstone 30, and a working fluid is supplied from a working fluid nozzle (not shown) to a contact point between the two, whereby the work is supplied. 76, especially the tip of the ball end mill is ground. At this time, similarly to the conventional NC device, the feed amount of each of the seven axes (A axis, B axis, X axis, Y axis, Z axis, U axis, W axis) is controlled by the NC device 84, The work 76 is ground into a desired shape.
[0026]
When the tip of the work 76 is ground, the grinding surface of the rotary grindstone 30 is also worn, but by setting the pressing force or the processing pressure of the work 76 against the rotary grindstone 30 to the optimum processing pressure, the rotation of the rotary grindstone 30 is reduced. On the ground surface, so-called spontaneous cutting occurs and a sufficient sharpness is maintained. In the present embodiment, the processing pressure is monitored by measuring the thrust force acting on the grinding wheel shaft 24 by the load cell 19. That is, when the processing pressure detected by the load cell 19 exceeds a predetermined value, the NC device 84 determines that the grinding surface of the rotary grindstone 30 is worn out and the sharpness of the rotary grindstone 30 is reduced, and will be described below. The dressing process is started. Further, when the sharpness of the rotary grindstone 30 decreases, the current value of the servomotor, especially the servomotor 62 as the U-axis feed motor increases, so that instead of the measurement of the thrust force of the grindstone shaft 24 by the load cell 19, the servomotor 62 The dressing process may be started when a current value supplied to the battery is measured and the current value exceeds a predetermined value.
[0027]
When the grinding of the work 76 is completed, the NC multi-axis grinding machine 10 can measure the outer shape of the work 76 on the machine while the work 76 is mounted on the work spindle 70. Next, a method for measuring the shape of the ground work 76 will be described with reference to FIGS.
[0028]
(1) First, the center O of the tip sphere of the ball end mill 76 _b Are arranged on the W axis. This can be done as follows. That is, the touch sensor 88 is oriented in the vertical direction by rotating the B axis, and then the touch sensor 88 is moved in the XY axis directions by the servomotors 48 and 54 to be arranged on the W axis. The XY coordinates of the touch sensor 88 at this time are defined as the origin W (0, 0).
[0029]
Next, the turntable 58 is rotated about the W axis by the servomotor 66, and the longitudinal center axis of the ball end mill 76 is made to coincide with X = 0. Next, the ball end mill 76 is advanced in the Y-axis direction as shown by the arrow A, and is brought into contact with the touch sensor 88 (see FIG. 3). This can be performed by using the servomotor 62 to advance the ball end mill 76 along the U axis, or by using the servomotor 48 to advance the column 14 along the Y axis.
[0030]
Next, as shown by an arrow B in FIG. 3, the touch sensor 88 is separated from the ball end mill 76 along the Y axis. Finally, the ball end mill 76 is further advanced along the Y axis, and the center O _b To the origin (see FIG. 4). This is due to the design radius R of the hemispherical tip of the ball end mill 76. ₀ By moving the ball end mill 76 along the Y-axis by a distance obtained by adding the radius of the touch sensor 88 to the ball end mill 76.
[0031]
(2) Next, by rotating the turntable 58 about the W axis, the ball end mill 76 is _b It is rotated around by a predetermined angle α, and is arranged at an angular position shown by (i) in FIG. In the illustrated embodiment, α is 22.5 °, but other angles such as 30 ° or 15 ° may be selected. As described above, by determining the angle α, the center O of the tip end spherical portion of the ball end mill 76 is obtained. _b The tip of the cutting edge to be measured is determined for each circumference α.
[0032]
(3) Next, the tip of the cutting edge is adjusted to the same height as the longitudinal center axis of the ball end mill 76 by rotating the A-axis. This can be done as follows. First, as shown by an arrow D in FIG. 5, the touch sensor 88 is advanced along the Y-axis, and a design radius R is calculated from the center Ob of the tip sphere of the ball end mill 76. ₀ Then, the touch sensor 88 is moved down along the Z-axis so that the tip of the touch sensor 88 is at the same height as the center axis of the ball end mill 76. Next, the A-axis is rotated until the tip of the cutting edge of the ball end mill 76 contacts the tip of the touch sensor 88.
[0033]
Although the touch sensor 88 is illustrated in FIG. 5 as having a relatively thick measuring probe, the touch sensor 88 has a measuring probe that is as thin as possible in order to prevent chipping of the cutting edge. Advantageously. In that case, it is difficult to bring the tip of the cutting edge of the ball end mill 76 into contact with the tip of the touch sensor 88. Therefore, as shown in FIG. Can also be arranged radially inward.
[0034]
(4) Next, as shown by an arrow E, when the touch sensor 88 is moved away from the ball end mill 76 along the Y axis and the touch sensor 88 is linearly moved along the Y axis, Is moved down along the Z-axis so that the tip of the cutting blade can come into contact therewith. Then, as shown by an arrow F in FIG. 6, the touch sensor 88 is caused to approach the cutting edge of the ball end mill 76 along the Y axis. Thus, according to the present embodiment, the touch sensor 88 is configured such that the tip of the cutting blade to be measured and the center O of the tip end of the ball end mill 76 are measured. _b Along the straight line connecting _b To approach from the outside in the radial direction. Then, from the mechanical coordinate system in the NC device at the time when both come into contact with each other, the center O _b And the distance between the cutting edge and the tip of the cutting blade are calculated. When calculating the distance, it is desirable to consider the radius of the touch sensor 88. Thus, the tip O of the cutting edge to be measured and the ball center O of the ball end mill 76 are measured. _b The touch sensor 88 along the straight line connecting _b , The outermost diameter actually cut by the cutting edge tip determined for each angle α can be measured.
[0035]
In the NC multi-axis grinding machine 10 also having the ball end mill measuring device of FIGS. 1 and 2, the touch sensor 88 is attached to the grinding wheel head 18, so that the touch sensor 88 can move in three orthogonal XYZ directions. I have. Therefore, moving the touch sensor 88 along the Y axis so that the height of the cutting edge is aligned with the central axis of the ball end mill 76 is very easy to understand and advantageous in creating a measurement program for the ball end mill 76. is there. In the present invention, the tip of the cutting edge to be measured and the center O of the tip sphere of the ball end mill 76 are measured. _b The touch sensor 88 along the straight line connecting _b It is important to perform the approach operation from the outside in the radial direction. Therefore, when the touch sensor 88 has an axis configuration other than the orthogonal three-axis system including the vertical axis line as in the NC multi-axis grinding machine 10, the touch sensor 88 does not need to be moved in the horizontal direction. In other words, it can be said that “the height of the cutting edge” means the position of the cutting edge when the moving direction of the touch sensor 88 is set as the horizontal reference.
[0036]
(5) Next, the above steps (2) to (4) are repeated, and the outer shape of the tip of the ball end mill 76 is measured over 180 °. By repeating the measurement in this manner, a graph as shown in FIG. 8 can be created. Based on this graph, the grinding amount at each angular position of the tip of the ball end mill 76 is determined, and the shape of the tip of the ball end mill 76 can be finished with high precision by the NC multi-axis grinding machine 10.
[0037]
Also, as understood from FIG. 8, the positions of 0 ° and 180 ° correspond to the radius of the side surface of the ball end mill. Therefore, the radius of the tool can be measured by measuring the distance between the longitudinal center axis of the tool that performs cutting on a side surface such as a reamer and the tip of the cutting edge using the above method.
[0038]
【The invention's effect】
According to the first aspect of the present invention, since the swivel table is provided so as to be rotatable around the vertical axis at the upper part of the bed, it is possible to increase the rigidity of the W axis.
According to the third aspect of the present invention, the tip of the cutting edge of the ball end mill to be measured is determined at every predetermined angle around the center of the tip of the ball end mill, and the center of the tip sphere of the ball end mill is determined. Move the sensor from the outside in the radial direction to the center of the ball end mill tip along a straight line connecting the determined cutting edge tip to be measured and the center of the ball end mill tip ball and the The distance from the tip of the cutting edge is measured at predetermined angles around the center of the ball sphere of the ball end mill, and from the measured value, the amount of grinding at the predetermined angle around the center of the ball sphere of the ball end mill. And grinding is performed, so that the grinding amount can be determined accurately, and the ball end mill can be ground with high precision.
[0039]
According to the present invention as set forth in claim 4, the ball end mill is rotated around the center axis of the ball end mill so that the tip of the cutting edge of the ball end mill is adjusted to the height of the center axis, and Since the sensor was moved along a straight line connecting the center and the tip of the cutting edge to measure the distance between the center of the tip sphere of the ball end mill and the tip of the cutting edge, the radius of the tip of the ball end mill was changed. It can be measured accurately. Further, by rotating the ball end mill by a predetermined angle about an axis passing through the center of the ball end mill tip ball portion and perpendicularly intersecting the longitudinal center axis of the ball end mill, the entire ball end mill tip portion can be accurately formed. The radius can be measured. Then, since the grinding amount is obtained at the predetermined angle around the center of the ball end mill tip ball portion from the obtained shape of the tip portion of the ball end mill, the grinding amount can be accurately determined, and the ball end mill can be used. High precision grinding is possible.
[0040]
According to the present invention as set forth in claim 5, the cutting edge of the ball end mill to be measured is determined at every predetermined angle around the center of the ball end mill tip ball portion, and the ball end mill tip ball portion is measured. By moving the sensor from the radial outside to the center of the ball end mill tip along a straight line connecting the center and the determined cutting edge tip to be measured, the center of the ball tip mill tip ball is moved. The distance between the tip and the cutting edge is measured at every predetermined angle around the center of the ball end mill tip ball, and from the measured value, around the center of the ball end mill tip ball at the predetermined angle. Since the grinding amount is determined, the grinding amount can be determined precisely, and the ball end mill can be ground with high precision.
[0041]
According to the present invention as set forth in claim 6, the ball end mill is rotated around the central axis of the ball end mill so that the tip of the cutting edge of the ball end mill is adjusted to the height of the central axis, and Since the sensor was moved along a straight line connecting the center and the tip of the cutting edge to measure the distance between the center of the tip sphere of the ball end mill and the tip of the cutting edge, the radius of the tip of the ball end mill was changed. It can be measured accurately. Furthermore, by rotating the ball end mill by a predetermined angle about an axis passing through the center of the ball end mill tip ball portion and perpendicular to the longitudinal center axis of the ball end mill, the ball end mill tip portion can be accurately adjusted over the entire ball end mill tip portion. The radius can be measured. Then, since the amount of grinding is determined at the predetermined angle around the center of the tip of the ball end mill from the determined shape of the tip of the ball end mill, the amount of grinding can be determined precisely, and the height of the ball end mill can be increased. It becomes possible to grind with high precision.
[0042]
According to the present invention as set forth in claim 8, the cutting edge of the ball end mill to be measured is determined for each predetermined angle around the center of the ball of the ball end mill. Move the sensor from the outside in the radial direction with respect to the center of the ball end mill tip ball along a straight line connecting the center and the determined cutting edge tip to be measured. Since the distance between the center and the tip of the cutting edge is measured at predetermined angles around the center of the tip sphere of the ball end mill, the outer shape of the tip of the ball end mill can be accurately measured. .
[0043]
According to the present invention as set forth in claims 9 and 12, the ball end mill is rotated around the center axis of the ball end mill to adjust the tip of the cutting edge of the ball end mill to the height of the center axis, and the tip ball of the ball end mill Since the sensor was moved along a straight line connecting the center of the part and the tip of the cutting edge to measure the distance between the center of the tip sphere of the ball end mill and the tip of the cutting edge, the tip of the tip of the ball end mill was measured. The radius can be measured accurately.
[0044]
According to the present invention as set forth in claim 18, in the method for measuring the shape of a rotating tool, the tip of the cutting edge of the tool is adjusted to the height of the central axis by rotating the tool around a central axis, and the cutting of the tool is performed. By measuring the distance between the blade tip and the central axis, it is possible to accurately measure the radius of a tool such as a reamer.
[Brief description of the drawings]
FIG. 1 is a schematic diagram of an NC multi-axis grinding machine according to a preferred embodiment of the present invention.
FIG. 2 is a schematic perspective view of the NC multi-axis grinding machine of FIG. 1;
FIG. 3 is a view for explaining a method of measuring the tip of a ball end mill according to a preferred embodiment of the present invention.
FIG. 4 is a view for explaining a method of measuring the tip of a ball end mill according to a preferred embodiment of the present invention.
FIG. 5 is a view for explaining a method of measuring a cutting edge of a ball end mill according to a preferred embodiment of the present invention.
FIG. 6 is a view for explaining a method of measuring a cutting edge of a ball end mill according to a preferred embodiment of the present invention.
FIG. 7 is a view for explaining a method of measuring a cutting edge of a ball end mill according to a preferred embodiment of the present invention.
FIG. 8 is a graph showing measurement results obtained by a method of measuring a cutting edge of a ball end mill according to a preferred embodiment of the present invention.
[Explanation of symbols]
10 ... NC multi-axis grinding machine
12 ... bed
12a ... Boss
14 ... Column
16 ... Wheel head feed
18 ... Whetstone head
19… Load cell
20 ... Dressa saddle
24 ... Whetstone axis
30 ... rotating whetstone
32 ... dresser feeder
36 ... Dresser tool
46 ... Table
50 ... Y axis feed screw
58 ... Turn table
58a: Turning table shaft
60 ... Work feeder
66 ... electric insulating plate
68 ... Work spindle head
70 Work spindle
76… Work
78 ... energizing brush
80: energizing brush
84 NC device
88 ... Touch sensor

Claims (19)

An NC multi-axis grinding machine that grinds the work by relative movement between the grinding tool and the work that rotates around a predetermined axis,
A bed as a base,
A column provided on the bed so as to be linearly movable in two horizontal axis directions orthogonal to each other;
A linear moving linearly in the vertical direction on the column, a grindstone head rotatably supporting a grindstone shaft for mounting the grinding tool,
A swivel provided on the bed so as to be rotatable around a vertical axis,
A work spindle head provided on the swivel table and supporting a work spindle for fixing the work so as to be rotatable around a horizontal axis;
NC multi-axis grinding machine characterized by comprising: 2. The NC multi-axis grinding machine according to claim 1, wherein the work spindle head is configured to be linearly movable manually or by numerical control on the swivel base along an axis parallel to the axis of the spindle head. 3. In the ball end mill grinding method,
Determine the cutting edge tip of the ball end mill to be measured at every predetermined angle around the center of the ball end mill tip ball portion, and determine the center of the ball end mill tip ball portion and the determined cutting edge tip to be measured. A sensor for reading the coordinate position is moved from the radial outside to the center of the tip sphere of the ball end mill along the connecting line, and the center of the tip sphere of the ball end mill and the tip of the cutting edge are moved. The distance was measured at each predetermined angle around the center of the ball end mill tip ball portion, and the grinding amount was obtained at each of the predetermined angles around the center of the ball end mill tip ball portion from the measured value, so that the grinding was performed. Ball end mill grinding method. In the ball end mill grinding method,
(A) a step of supporting the ball end mill rotatably about a longitudinal central axis and about an axis perpendicular to the central axis by work supporting means;
(B) rotating the ball end mill around the center axis to adjust the tip of the ball end mill to the height of the center axis;
(C) moving a sensor for reading a coordinate position along a straight line connecting the center of the tip sphere of the ball end mill and the tip of the cutting edge to move the sensor between the center of the tip sphere of the ball end mill and the tip of the cutting edge; Measuring the distance;
(D) rotating the ball end mill by a predetermined angle about an axis passing through the center of the ball portion of the ball end mill and perpendicularly intersecting the longitudinal center axis of the ball end mill;
The steps (b), (c) and (d) are repeated to measure the shape of the ball end mill tip at every predetermined angle around the center of the tip ball of the ball end mill;
A grinding method of a ball end mill, wherein a grinding amount is obtained at every predetermined angle around the center of the ball end mill tip ball portion from the determined shape of the tip portion of the ball end mill, and grinding is performed. In a ball end mill grinding apparatus for grinding the ball end mill by relative movement between a grinding tool rotating around a predetermined axis and a ball end mill,
A bed as a base,
A column provided on the bed so as to be linearly movable in two horizontal axis directions orthogonal to each other;
A linear moving linearly in the vertical direction on the column, a grindstone head rotatably supporting a grindstone shaft for mounting the grinding tool,
A swivel provided on the bed so as to be rotatable around a vertical axis,
A work spindle head provided on the swivel table and supporting a work spindle for fixing the ball end mill rotatably about a horizontal axis;
A sensor for reading the coordinate position attached to the grinding head,
The swivel is rotated about a vertical axis, indexed, and the tip of the cutting edge of the ball end mill to be measured at predetermined angles around the center of the tip ball of the ball end mill is determined, and the center of the tip ball of the ball end mill is determined. Move the sensor from the radial outside to the center of the ball end mill tip along a straight line connecting the determined cutting edge tip to be measured and the center of the ball end mill tip ball. The distance from the tip of the cutting edge is measured at predetermined angles around the center of the ball end mill tip of the ball end mill, and from the measured value, the amount of grinding at the predetermined angle around the center of the ball end mill tip ball portion. Grinding machine for ball end mills that seeks and grinds. In a ball end mill grinding apparatus for grinding the ball end mill by relative movement between a grinding tool rotating around a predetermined axis and a ball end mill,
A bed as a base,
A column provided on the bed so as to be linearly movable in two horizontal axis directions orthogonal to each other;
A linear moving linearly in the vertical direction on the column, a grindstone head rotatably supporting a grindstone shaft for mounting the grinding tool,
A swivel provided on the bed so as to be rotatable around a vertical axis,
A work spindle head provided on the swivel table and supporting a work spindle for fixing the ball end mill rotatably about a horizontal axis;
A sensor for reading the coordinate position attached to the grinding head,
(A) supporting the ball end mill on the work spindle;
(B) rotating the work spindle to rotate the ball end mill around its longitudinal center axis to adjust the tip of the blade end of the ball end mill to the height of the center axis;
(C) moving the sensor along a straight line connecting the center of the ball tip end of the ball end mill and the tip of the cutting edge to measure the distance between the center of the ball tip end of the ball end mill and the tip of the cutting edge; Process and
(D) rotating the swivel base to rotate the ball end mill by a predetermined angle around an axis passing through the center of the ball portion of the ball end mill and perpendicular to the longitudinal center axis of the ball end mill;
The steps (b), (c) and (d) are repeated to measure the shape of the tip of the ball end mill at every predetermined angle around the center of the tip of the ball end mill;
A grinding machine for a ball end mill, wherein a grinding amount is determined for each predetermined angle around the center of the ball end mill tip ball portion from the determined shape of the tip portion of the ball end mill, and the grinding is performed. The grinding apparatus for a ball end mill according to claim 5, wherein the workpiece spindle head is configured to be capable of linearly moving manually or by numerical control along an axis parallel to the axis of the spindle head on the swivel table. In the method of measuring the shape of a ball end mill,
Determine the cutting edge tip of the ball end mill to be measured at every predetermined angle around the center of the ball end mill tip ball portion, and determine the center of the ball end mill tip ball portion and the determined cutting edge tip to be measured. A sensor for reading the coordinate position is moved from the radial outside to the center of the tip sphere of the ball end mill along the connecting line, and the center of the tip sphere of the ball end mill and the tip of the cutting edge are moved. A method of measuring the shape of a ball end mill, wherein the distance is measured at predetermined angles around the center of the ball portion of the ball end mill. In the method of measuring the shape of a ball end mill,
(A) supporting the ball end mill rotatably about a longitudinal central axis;
(B) rotating the ball end mill around the center axis to adjust the tip of the ball end mill to the height of the center axis;
(C) moving a sensor for reading a coordinate position along a straight line connecting the center of the tip sphere of the ball end mill and the tip of the cutting edge to move the sensor between the center of the tip sphere of the ball end mill and the tip of the cutting edge; Measuring the distance;
A method for measuring the shape of a ball end mill, comprising: The measuring method further includes the step of (d) rotating the ball end mill by a predetermined angle around an axis passing through the center of the ball portion of the ball end mill and perpendicularly intersecting the longitudinal center axis of the ball end mill,
The method for measuring the shape of a ball end mill according to claim 9, wherein the steps (b), (c) and (d) are repeated. The step of measuring the distance between the center of the ball end mill and the tip of the cutting edge is performed along a straight line connecting the center of the ball end mill and the cutting edge. 11. The method according to claim 9, wherein a sensor for reading a coordinate position is approached to the tip of the cutting blade from outside in the radial direction with respect to the center of the spherical portion, and the sensor is brought into contact with the tip of the cutting blade. Method. In the ball end mill shape measuring device,
Work supporting means for supporting the ball end mill rotatably about a longitudinal central axis and an axis perpendicular to the central axis,
Moving means for relatively linearly moving a coordinate position reading sensor relative to the ball end mill along three orthogonal axes,
The ball end mill is rotated around the center axis to adjust the tip of the cutting edge of the ball end mill to the height of the center axis, and the sensor is arranged along a straight line connecting the center of the tip sphere of the ball end mill and the tip of the cutting edge. Is moved to measure the distance between the center of the ball end of the ball end mill and the tip of the cutting edge. The work support means includes a work spindle head rotatably supporting a work spindle on which the ball end mill is mounted at the tip and being horizontally oriented, and a swivel table rotatably supporting the work spindle head around a vertical axis. The shape measuring device for a ball end mill according to claim 12. 14. The ball end mill shape measuring device according to claim 13, wherein the work spindle head is provided on the revolving base so as to be able to linearly move in the central axis direction of the work spindle by manual or numerical control. 15. The ball end mill shape measuring apparatus according to claim 13, wherein the moving unit linearly moves the sensor along two horizontal axes orthogonal to each other and a vertical axis perpendicular to the two horizontal axes. The moving means includes a column provided linearly movable in two horizontal axis directions orthogonal to each other at an upper portion of a bed serving as a base, and a sensor mounting member that linearly moves vertically on the column and supports the sensor. The ball end mill shape measuring device according to claim 15, comprising: 17. The shape measuring device for a ball end mill according to claim 16, wherein the swivel table is provided on the bed so as to be rotatable about the vertical axis. In the method of measuring the shape of a rotating tool,
(A) supporting the tool rotatably about a longitudinal central axis;
(B) rotating the tool around the center axis to adjust the cutting edge of the tool to the height of the center axis;
(C) measuring the distance between the cutting edge of the tool and the central axis;
A method for measuring the shape of a rotary tool, comprising: The step of measuring the distance between the cutting edge of the tool and the central axis line is such that a coordinate position reading sensor approaches the cutting edge from outside in the radial direction, and the sensor and the cutting edge are connected. 19. The method for measuring the shape of a rotary tool according to claim 18, wherein the method is performed by contacting.

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