JPH0760622A - Grinding device for twist end mill - Google Patents

Abstract

PURPOSE:To enable precise grinding at low cost without reading in an edge tip shape by controlling rotation of a work main shaft according to a signal to show a contact condition with the cutting edge while moving a work contact detecting means in synchronism with a grinding tool when the edge tip is ground. CONSTITUTION:When grinding work is carried out on a part running along the edge tip (a line to be ground) 3c of a work 3 where three edges 3a are formed in a spiral shape in the axis direction, a grinding wheel head 7 is advanced in the X axis direction, and a grinding wheel 9 is brought into contact with a work start position to start notching of the line 3c to be ground of the work edges 3a. The line 3c to be ground of the work 3 is brough successively into contact with a grinding surface 9a, and the work 3 is ground along the line 3c to be ground up to a work finish position from the work start position. In this case, whether or not the grinding wheel 9 comes into contact with the edges 3a of the work 3 is detected by a touch sensor 16 always situated on the front side of the grinding wheel 9, and a work main shaft 2, that is, rotation of a motor 5 is controlled in a feedback process so that the signal 51 is always put on.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a grinding device for a twist end mill, which is used for grinding a cutting edge of a twist end mill.

[0002]

2. Description of the Related Art Conventionally, for grinding the cutting edge of a twist end mill, while rotating the grinding wheel, the grinding wheel is automatically fed in the axial direction of the work axis, while the work spindle equipped with the work for the twist end mill. While the machine is manually rotated, the grinding wheel is brought into contact with the position to be ground of the workpiece to perform grinding. However, this method requires a skilled operator to perform a skillful operation, and the finished state of the work becomes uneven depending on the skill of the operator, so that there is a disadvantage that a twist end mill with high machining accuracy cannot be obtained. It was Therefore, by using a computer, the shape of the cutting edge is read in advance and converted into a digital signal, and the work is rotated based on the digital signal so as to eliminate the unevenness of the grinding process due to the difference in the machining operator. An NC machine has been developed that performs profile processing.

[0003]

However, in a twist end mill, a plurality of blades are usually blade-cut, and the finished shapes of the plurality of blades are slightly different from each other. Therefore, in the case of performing such a flattening process, it is necessary to perform a work of reading the shape of the cutting edge to be ground by a stylus or the like before grinding each cutting edge one by one. The lead time becomes very long. Further, in such an NC machine, a memory for reading the shape of the cutting edge and storing the shape is required, which naturally increases the machine cost. For this reason, in processing such as producing small lots,
It is extremely difficult to obtain a precise twist end mill by introducing such an NC machine from the economical aspect. Therefore, in view of the above circumstances, the present invention provides a grinding machine for a twist end mill, which does not need to read the shape of the cutting edge when grinding a twist end mill and enables precise grinding at low cost.

[0004]

That is, according to the present invention, a work spindle () capable of rotatably holding a work (3) for a twist end mill having a plurality of spiral cutting blades (3a) formed in the axial direction. 2), and the cutting blade (3) of the work (3)
A grinding tool (9) capable of grinding the cutting edge (3c) of a) is provided so as to be movable relative to the work (3) in the axial direction of the work spindle (2), and the work (3) is provided. Workpiece contact detection means (16) for detecting the contact state with the cutting blade (3a) of the workpiece is provided so as to be movable relative to the workpiece spindle (2) in the axial direction of the workpiece spindle (2), and the grinding is performed. Synchronous movement means (6, 7) capable of moving the tool (9) and the work contact detection means (16) relative to the work spindle (2) in the axial direction of the work spindle (2) relative to each other. Workpiece spindle rotation drive control means (5, 22, 2) which is provided and controls the rotation of the workpiece spindle (2) based on the signal (S1) output from the workpiece contact detection means (16).
5) is provided and configured. The numbers in parentheses () indicate the corresponding elements in the drawings for convenience, and therefore the present description is not limited to the description in the drawings. The same applies to the following action columns.

[0005]

With the above-mentioned structure, the present invention provides the cutting edge (3c).
When grinding the workpiece, the cutting blade (3a) output to the work contact detection means (16) while the work contact detection means (16) is moved synchronously with the grinding tool (9) by the synchronous movement means (6, 7). Work spindle rotation drive control means (5, 22, 25) based on the signal (S1) indicating the contact state with
To control the rotation of the work spindle (2).

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a front view showing an example of a twist end mill during grinding using the present invention, FIG. 2 is a view taken in the direction of arrow II in FIG. 1, and FIG. 3 is a work line shape in the twist end mill shown in FIG. 4 is a plan view showing the control system of the processing apparatus for twist end mills according to the present invention, FIG.
3 is a flow chart showing a grinding process of the twisting end mill grinding device according to the present invention.

As shown in FIG. 1 or 2, a grinding machine 1 to which a grinding device for a twist end mill according to the present invention is applied can detachably hold a metal work 3 to be a twist end mill by grinding. The work spindle 2 is provided, and the work 3 is already formed by cutting a predetermined number of blades 3a that are spiral cutting blades in the axial direction of the work 3 and forming a spiral groove 3d in the work 3. In this form, it is rotatably held on the work spindle 2 as a work for a twist end mill to be ground. The work spindle 2 has a first motor 5 for rotationally driving the work spindle 2.
Is connected, and the first motor 5 turns the work spindle 2 around the rotation center CL2, which is the axis of the work spindle 2, so as to be rotatable around the Z axis shown in the directions of arrows M and N in the figure. Has become.

In addition, as shown in FIG. 1 or 2, the rest base 6 of the grinder 1 is fed and moved along the Z-axis direction shown by the arrows E and F in FIG. 1 (the direction intersecting the plane of FIG. 2). The second motor 11 is connected to the rest base 6 via a ball screw 12 so as to be rotatable and driven in the directions of arrows R and S. The second motor 11 is configured so that the rest base 6 can be moved along the Z-axis direction shown by the arrows E and F in FIG. 1 by the rotational driving operation of the second motor 11. 2, the grindstone head 7 is mounted in such a manner that it can be moved forward and backward along the X-axis direction shown by the arrows A and B in FIG. 2 (direction intersecting the plane of FIG. 1). In the grindstone head 7, a grindstone 9 formed in a disk shape as a grinding tool that can grind a line to be ground 3c that is a cutting edge of the blade 3a of the work 3 via a grindstone shaft 91 that is a tool driving shaft, The grindstone 9 is mounted so as to be rotatable in the directions P and Q in the drawing about a rotation center CL1 which is the axis of the grindstone shaft 91, and the grindstone 9 moves along with the movement of the rest base 6 in the directions E and F. By moving along the directions of the arrows E and F, which are the axial directions of the work spindle 2, the work spindle 3 is movable relative to the work 3. The grindstone 9 is an outer peripheral grinding tool having a grinding surface 9a formed on the outer periphery thereof, and the grindstone 9 rotates in the arrow P or Q direction via a tool drive motor 10 connected to a grindstone shaft 91. By the operation, the cutting edge located on the outer peripheral surface portion along each blade 3a of the work 3, that is, the line to be ground 3c can be spirally ground for each blade 3a.

Further, the grinding machine 1 includes a grinding processing control device 1
3 is provided, and the grinding processing control device 13 has a configuration shown in FIG.
As shown in FIG. 3, a positioning sensor 15 that can position the grinding start position of the work 3 by the grindstone 9 is provided in a position corresponding to the end surface 3b portion of the work 3, and the positioning sensor 15 has As shown in FIG. 2, a casing 151 is provided outside the work 3 along the outer circumference of the work 3. Casing 15
1, a plurality of detecting portions 15p of the positioning sensor 15 are provided in such a manner that they form a predetermined angle with respect to the rotation center CL2 of the work spindle 2 respectively.
Is detected by any one of the detection units 15P from the processing start position P0 of the blade 3a at which the cutting edge is to be ground, and the processing start position P0 ′ of another blade 3a arranged at a predetermined angle α on the arrow N direction side. Can be detected.

That is, the casing 1 of the positioning sensor 15
The 51 is provided with a plurality of detectors 15P arranged in a position that forms a predetermined angle α of 90 degrees, 120 degrees, 180 degrees or the like from the reference position X1 set in the positioning sensor 15. The positioning sensor 15 is configured to be able to effectively operate only a predetermined detection unit 15P selected by the angle α set according to the number of blades 3a formed on the work 3. Therefore, in the embodiment shown in FIG. 2, since the work 3 is provided with the three blades 3a, the positioning sensor 15 now selectively selects only the detecting portion 15P that makes an angle of 120 degrees from the reference position X1. And the detection unit 15P at the 120-degree position,
The other blade 3a at a position forming an angle of 120 degrees from the processing start position P0 of the blade 3a to be grounded to the arrow N direction side.
The processing start position P0 ′ of No. 1 can be detected.
The grinding control device 13 determines that the number of blades 3a, which are cutting blades for twist end mills formed on the work 3, is
In the case of other than the three blades described in the embodiment, the detecting portion 15p of the positioning sensor 15 according to the formation pitch angle of the blade 3a is made effective and the above-described blade 3a detecting operation can be performed. That is, when two cutting blades are formed on the work, the detection unit 1 forming an angle of 180 degrees from the reference position X1.
Only 5P is effective, and when four cutting blades are formed on the work, by effectively operating only the detection unit 15P forming an angle of 90 degrees from the reference position,
The processing start position of each blade can be detected according to the number of workpiece cutting blades.

Further, in the grinding control device 13, as shown in FIG. 1 or 2, the touch sensor 16 is always positioned on the arrow A direction side which is the front side of the grindstone 9 so that the blade 3a of the work 3 is positioned. The touch sensor 16 corresponds to the radius of the workpiece 3 to be ground from the axis CL2 of the work spindle 2 in a position slightly inward of the grinding line 3c to be ground (on the axis CL2 side). It is mounted on the rest base 6 in such a manner that it can be driven to project and retreat in the vertical direction indicated by the arrows G and H on the arrow B direction side by the distance L1. The position of the touch sensor 16 in the directions of arrows A and B can be arbitrarily adjusted and set according to the radius of the work 3 to be processed. The touch sensor 16 determines whether or not the touch sensor 16 is in contact with the blade 3a of the work 3 in such a manner that it becomes an electric contact when the tip end portion shown in FIG. The touch sensor 16 can be detected by the ON / OFF output of the signal S1. Therefore, the touch sensor 16 moves in synchronization with the grindstone 9 by using the rest base 6 and the grindstone head 7 as the synchronous moving means in synchronization with the work spindle 2. Work contact while detecting relative contact with the blade 3a of the work 3 held by the work spindle 2 while moving relative to the work spindle 2 in the axial direction (arrow E, F direction) of It is in the form of a detecting means.

Further, as shown in FIG. 4, the grinding control device 13 has a main control unit 20, and the main control unit 20 has a machining start position indexing unit 21, a signal judging unit 22, and a grindstone. The rotary drive unit 23, the work shaft rotation control unit 25, the grindstone feed control unit 26, the grindstone shaft forward drive control unit 27, the keyboard 29, etc. are connected. Each of the detection units 15P of the positioning sensor 15 is connected to the processing start position indexing unit 21, and the touch sensor 16 is connected to the signal determining unit 22, respectively,
Further, the work shaft rotation control unit 25 includes the first motor 5
However, the second motor 11 is connected to the grindstone feed control unit 26. Further, the tool drive motor 10 is connected to the grindstone rotation drive unit 23, and the X-axis actuator 28 is connected to the grindstone shaft forward drive control unit 27. The signal determination unit 22, the work shaft rotation control unit 25, and the first motor 5 control the rotation of the work spindle 2 based on the signal S1 from the touch sensor 16 that is the work contact detection means. The main shaft rotation driving means is configured.

Since the grinding machine 1 has the above-described structure, the grinding machine 1 is used to form the work in which the three blades 3a are spirally formed in the axial direction as described above. In order to grind a portion along the line to be ground 3c which is the cutting edge of 3, the work 3 is first held on the work spindle 2. In this state, as shown in FIG. 3, the grindstone head 7 is moved forward along the X-axis direction in the direction of the arrow A, so that the cut line 3c of the blade 3a to be ground in the work 3 is cut. The grindstone 9 is brought into contact with the processing start position P0 to be started.
Then, while the grindstone 9 is rotationally driven in the direction of arrow Q in FIG. 3 about the rotation center CL1, the grindstone 9 is moved relative to the work 3 in FIG. Is moved in the direction of arrow F, and the work spindle 2 is rotated about the rotation center CL2 as shown in FIG.
In, the rotation is made in the direction of arrow M. As a result, the grinding line 3c of the work 3 is sequentially brought into contact with the grinding surface 9a, and along the grinding line 3c, which is the cutting edge of the blade 3a of the work 3, from the processing start position P0 to the processing end position P1. Then, the work 3 is ground. At this time, the grinding control device 13
Then, the touch sensor 16 which is always located on the arrow A direction side which is the front side of the grindstone 9 is caused to detect whether or not it is in contact with the blade 3a of the work 3 by turning the signal S1 ON and OFF, and the signal S1 is always As it is turned on, the rotation of the work spindle 2, that is, the rotation driving amount of the work 3 due to this, is feedback-controlled by the signal determination unit 22, the work shaft rotation control unit 25, and the first motor 5. As a result, the grinding surface 9a of the grindstone 9 that moves in the direction of arrow F in synchronization with the touch sensor 16 controls so that the blade 3a of the work 3 can be accurately ground along the line to be ground 3c.

Therefore, when performing the grinding process, the grinding process control device 13 is used to perform the machining process PRO shown in FIG.
The work 3 on which the blades 3a, which are spiral cutting blades, have already been formed along the above, is processed in such a manner that the portion to be ground 3c, which is the cutting edge corresponding to each blade 3a, is ground. Therefore, first, in step ST1 in FIG. 5, the work 3 to be ground is mounted on the work spindle 2. At the start of processing, the grindstone 9 is moved along the X-axis in the direction of the arrow B so that the grindstone 9 is located at the retracted position BG as shown by the alternate long and short dash line in FIG. Retreat. Further, at this time, the touch sensor 16 is retracted from the state shown in FIG. 2 to the position lowered in the direction of the arrow H. In this state, in step ST2 of FIG. 5, the operator inputs the number N of blades of the work 3 to be ground from the keyboard 29, and also inputs the processing start command SC to the grinding control device 13 to input the grinding start command SC to the grinding machine. The grinding process according to 1 is started.

Then, first, the main control unit 20 causes the work shaft rotation control unit 25 to drive the first motor 5 in step ST3 of FIG. 5, thereby causing the first motor 5 to start rotation. Then, by the rotation of the first motor 5, the work spindle 2 rotates in the direction of arrow M or N,
The work 3 rotates about the Z axis around the rotation center CL2. Therefore, next, in step ST4 of FIG. 5, the processing start position indexing section 21 selectively enables the detecting section 15P of the positioning sensor 15 corresponding to the input number N of blades (in the case of the embodiment, the detecting section 15P2 The positioning sensor 15 is caused to detect a machining start position P0 ′ of another blade 3a at a position forming an angle of 120 degrees in the arrow N direction side from the machining start position P0 of the blade 3a to be ground. . That is, in the embodiment, the detection unit 15P2 at a position 120 degrees from the machining start position P0 to be positioned is effectively operated, and the work 3 is rotated in this state. Then,
The positioning sensor 15 detects the line to be ground 3c, which is the cutting edge of the blade 3a arranged at a position forming an angle of 120 degrees with respect to the reference position X1, and the blade 3a to be ground from now on.
The grind line 3c of the blade 3a on the side of the 120 degree arrow N,
That is, the processing start position P0 'is detected. Therefore, the main control unit 20 causes the machining start position indexing unit 21 to perform a step ST5 in FIG.
Thus, the processing start position P0 is indexed to the reference position X1 based on the output signal of the positioning sensor 15. In response to this, the main controller 20 receives the work axis rotation controller 2
5, the processing start position P0 of the blade 3a to be ground
Causes the first motor 5 to be temporarily stopped in such a manner that the work 3 is positioned at the reference position X1 facing the grinding surface 9a of the grindstone 9.

When the touch sensor 16 is driven to project in the direction of arrow G in this state, the projecting tip of the touch sensor 16 moves from the axis CL2 of the work spindle 2 to the radius of the work 3, as shown in FIG. The blade 3 positioned at the reference position X1 in the groove 3d located at the corresponding distance L1
The blade 3a contacts the blade 3a slightly inward of the line to be ground 3c to be ground at a (on the workpiece main axis CL2 side). As a result, the touch sensor 16 determines the signal S1 in a predetermined manner in the direction of the arrow A, which is the front side of the grindstone 9, in such a manner that the tip portion thereof serves as an electrical contact point and detects the contact state with the blade 3a of the work 3. ON or OFF output starts in a cycle. Therefore, the main control unit 20 controls the grindstone rotation drive unit 23.
The tool driving motor 10 is driven to rotate the grindstone 9 around the Z axis shown in the arrow P or Q direction around the rotation center CL1 via the grindstone shaft 91. At the same time, the main control unit 20 causes the grindstone shaft forward drive control unit 27 to move to X
The axis actuator 28 is driven to move the grindstone head 7 to the X axis.
The grinding surface 9a of the grindstone 9 mounted on the grindstone head 7 is brought into contact with the blade 3a of the work 3 with a predetermined pressing force by advancing along the axial direction toward the arrow A direction. Then, the work surface 3c is ground in such a manner that the work 3 is ground by the amount of contact with the grindstone 9.

That is, in order to perform grinding, first, in step ST6 in FIG. 5, as shown in FIG.
a is brought into contact with the machining start position P0 of the blade 3a of the work 3. In this state, in step ST7 in FIG. 5, the main control unit 20 causes the grindstone feed control unit 26 to move to the second motor 1.
1 is rotated at a predetermined rotation speed in the arrow R direction or the S direction. That is, the rest base 6 is moved in the arrow F direction along the Z-axis direction by the ball screw 12 by an amount corresponding to the rotation amount of the second motor 11. In this way, when the rest base 6 is moved in the direction of the arrow F, the grindstone 9 that is being driven to rotate about the rotation center CL1 will be
As shown in FIG. 5, the second motor 11 moves in the arrow F direction along the Z-axis direction by an amount corresponding to the rotation amount of the second motor 11. Then, the grinding surface 9a of the grindstone 9 and the grinding line 3c of the work 3 are moved in a direction in which the grinding surface 9a moves in the direction of arrow F in FIG. 3 with respect to the spiral grinding target line 3c shown by the one-dot chain line in FIG. The work 3 separates from the grindstone 9 in the direction of arrow N relative to the amount corresponding to the rotational drive amount of the second motor 11. In this way, when the grinding surface 9a and the grinding target line 3c separate from each other, the grindstone 9
The touch sensor 16 mounted on the rest base 6 so as to be positioned on the arrow A direction side, which is the front side of the, in the direction of the arrow F in the groove 3d of the work 3 synchronously with the grindstone 9 via the rest base 6. By moving, it becomes a non-contact state with the to-be-ground line 3c of the blade 3a. As a result, the touch sensor 16 immediately outputs the signal S1 in the OFF state in the form of no electrical contact with the blade 3a of the work 3.

Therefore, the main control unit 20 outputs the signal S1 of the touch sensor 16 to the signal determining unit 22 at a predetermined cycle.
It is determined whether it is N or OFF, and the work shaft rotation control unit 25 turns on the first motor 5 for each OFF output.
The work 3 is rotated in the arrow M direction by rotationally driving until the signal S1 is output. When the work 3 rotates in the direction of the arrow M, the tip of the touch sensor 16 that has been separated until then comes into contact with the work 3 again, and the signal S1 is turned on.
Becomes When the signal S1 is turned on, the first motor 5 is stopped, and the rotation of the work 3 in the arrow M direction is stopped. In this state, the grinding surface 9a of the grindstone 9 and the line to be ground 3c are in proper contact with each other in the directions of the arrows M, N (P, Q), so that the blade 3a of the work 3 is properly ground. By repeating such control, it is possible to keep the grindstone 9 always in proper contact with the blade 3a. Therefore, as described above, in step ST7 of FIG. 5, while the second motor 11 is rotated at a predetermined rotation speed, in this state, the signal S1 of the touch sensor 16 is sent to the signal determination unit 22 at predetermined intervals. ON and OFF are detected and judged. If the signal S1 of the touch sensor 16 is OFF output in step ST8 of FIG.
In step ST9, the first motor 5 is moved to the touch sensor 1
Rotate until the signal S1 of 6 turns on. Then, the main control unit 20 performs the operation of the steps ST7 to ST9 in FIG. 5 until the grindstone 9 which is the grinding tool reaches the machining end position P1 (shown in FIG. 3) which is the work end in step ST10 of FIG. To do.

Then, the first motor 5 has the grindstone 9 and the arrow F.
O of the signal S1 of the touch sensor 16 that moves synchronously in the direction
The drive amount is controlled so that the signal S1 is always ON based on N and OFF, so that the touch sensor 16 is always at a position where the touch sensor 16 forms a predetermined distance L1 from the axis CL2 of the work spindle 2. At the blade 3a of the work 3
The rotation of the work 3 is controlled so as to maintain a state in which the blade 3a contacts the grinding surface 9a of the grindstone 9 at the reference position X1. As a result, the grindstone 9 can always grind the ground line 3c, which is the cutting edge of the blade 3a, by a predetermined depth, with the grinding surface 9a always in contact with the blade 3a of the work 3. In this way, at the part to be ground 3c corresponding to one blade 3a to be ground,
From the processing start position P0 to the processing end position P1, as described above, while making the rotation amount of the work spindle 2 by the first motor 5 follow the grindstone feed movement amount by the second motor 11,
When the work 3 and the grindstone 9 are moved relative to each other in the direction of the arrow F, the one grinding line 3c corresponding to the one blade 3a is surely ground into a predetermined shape.

Then, in step ST11 in FIG. 5, the main control unit 20 causes the grindstone shaft forward drive control unit 27 to operate the X-axis actuator 28 to move the grindstone 9 and the rest 6 of the grindstone 9 to the grindstone shaft. 91 is the retracted position B shown in FIG.
2 is moved backward along the X-axis direction shown in the arrow B direction in FIG. 2 and the rest base 6 is moved to the machining start position in the arrow E direction by the second motor 11 via the grindstone feed control unit 26. return. By the process of steps ST1 to ST12 described above, one of the works 3
The grinding of one line to be ground 3c of the blade 3a is completed. Therefore, next, again returning to step ST3 of FIG. 5, the first motor 5 is started to rotate, and step ST of FIG.
4 and ST5, the positioning sensor 15 and the machining start position indexing portion 21 are caused to index the machining start position of the ground line 3c to be newly ground, so that the grinding line 3c to be newly ground is first cut. The steps from ST6 to ST11 described above are repeated. In this way, by the machining process PRO shown in FIG. 5, when the above steps are repeated by the number of times corresponding to the number of the ground lines 3c which are the cutting edges of the blades 3a of the work 3, the cutting edges of all the blades 3a of the work 3 are obtained. The grinding of the line 3c to be ground is completed. During the grinding,
As described above, the rotation amount of the work spindle 2 is controlled so that the grindstone 9 and the touch sensor 16 that moves synchronously in the direction of the arrow F are always in contact with the blade 3a of the work 3. 3 is ground while being rotated so that the portion to be ground 3c always maintains the state in which it is accurately in contact with the grindstone 9. As a result, a uniform blade edge having a predetermined shape is ground on each of the plurality of blades 3a of the work 3 along the line to be ground 3c without any difference. Therefore, FIG.
In step ST13, the work 3 is removed from the work spindle 2.

Thus, in the predetermined number of blades 3a to be ground, the grindstone 9 is moved in the arrow F direction relative to the work 3 by the rotation of the second motor 11 as described above, while the first motor 5 moves. The rotation, that is, the rotation of the work 3 mounted on the work spindle 2 is changed to O of the signal S1 of the touch sensor 16.
By controlling on the basis of N and OFF, the grinding stone 9 and the work 3 are moved from the machining start position P0 to the machining end position P1
And are accurately moved relative to each other to grind a plurality of lines to be ground 3c. Then, each of the lines to be processed 3c ground by this is always finished in a state where the ground surface 9a of the grindstone 9 and the lines to be ground 3c are in proper contact with each other. Therefore, each of the plurality of lines to be ground 3c is ground into a uniform shape, and the work 3 becomes a twist end mill having a precise shape. When the twist end mill is ground and finished in this way, in the grinder 1, the line to be ground 3c
In order to grind the work 3 once along the direction, the grinding surface 9a of the grindstone 9 is moved once relative to the blade 3a of the work 3 from the processing start position P0 to the processing end position P1 as shown in FIG. Just let me. That is, according to the present invention, the line to be ground 3 is formed in a form prior to the actual machining, such as so-called profile machining.
Since it is not necessary to move a stylus or the like for reading this along the shape of c on the work 3, the processing procedure is simple. Further, since the grinding process can be started immediately by simply attaching the work 3 to the work spindle 2, the machining lead time is short and the total machining time required for the twist end mill is short. Further, as described above, when performing precision machining so that each of the lines to be machined 3c is ground in a uniform state, the grinding surface 9a of the grindstone 9 is always the blade 3a of the work 3.
Since the operation of following and controlling the rotation of the work spindle 2 so as to bring the workpiece into contact with the robot can be automatically performed by the grinding control device 13, no skilled technique is required for the operator. Therefore, depending on the operator, each line to be ground 3c
Alternatively, the finished state of grinding of each work 3 does not become inhomogeneous, and it is possible to easily perform a precise grinding process in which the lines to be ground 3c of a plurality of works to be machined are uniform. In addition, the grinder 1 reads the shape of the cutting edge,
By not needing memory to store this,
The machine cost is relatively low, so the twist end mill can be precisely ground and finished at low cost.

In the above-described embodiment, the grindstone 9 which is a grinding tool is mounted on the grindstone head 7 which can be moved forward and backward along the X-axis direction, and the grindstone head 7 is Z-shaped.
Although the example of being mounted on the rest base 6 which is movable along the axial direction has been described, the grindstone 9 is provided so as to be movable relative to the work 3 in the axial direction of the work spindle 2. However, it may be arranged in any other manner. Therefore, in the grindstone 9, as described in the embodiment, the rest base 6 supporting the grindstone 9 has the second motor 11 through the ball screw 12.
By the movement of moving in the Z-axis direction by the rotation drive of
It does not need to move relative to the work 3. That is, the grinder 1 is configured such that the grindstone 9 and the work 3 are relatively movable by moving the work 3 side in the Z-axis direction with respect to the rest base 6 and the like via the work main shaft 2. I don't mind. The material of the grinding tool such as the grindstone 9 is arbitrary. Further, in the embodiment, the example in which the touch sensor 16 mounted on the rest base 6 in a state of being always positioned on the front side of the grindstone 9 (on the side of the arrow A) is used as the work contact detection sensor has been described. The contact detection sensor may be provided in another position in another arrangement as long as it can detect the contact state with the blade 3a of the work 3 while moving in synchronization with the grindstone 9. . The touch sensor 16 is the touch sensor 1 in the embodiment.
6 is fixedly mounted on the rest base 6 as a synchronous movement means,
The example in which the grindstone 9 and the work spindle 2 are configured to be synchronously movable in the axial direction of the work spindle 2 has been described, but the construction of the synchronous moving means is not limited to this. Not a thing. Therefore, the touch sensor 16 may be configured so as to be able to move in synchronization with the grindstone 9 via a clutch or the like, and the touch sensor 16 is synchronized with the grindstone 9 in a form preceding the grindstone 9 in the arrow F direction. The contact state with the blade 3a may be detected while moving. Furthermore, the touch sensor 16 may detect the contact state with the blade 3a of the work 3 while moving in synchronization with the grindstone 9 by other means. In the embodiment, the touch sensor 16 indicates the contact state with the blade 3a of the work 3 by turning on and off the signal S1.
Although an example in which the signal determination unit 22 is configured to be able to immediately determine whether the signal S1 is turned on or off is described in the present invention, in the present invention, the work spindle rotation drive is performed based on the signal S1. It suffices that the control means can control the rotation of the work spindle 2. Therefore, the output and reading format of the signal S1 and the like may be other than those in the embodiment. The work spindle rotation drive control unit does not necessarily have to be configured by the first motor 5, the signal determination unit 22, and the work shaft rotation control unit 25 as described in the embodiment, but is configured by other components. May be done.

[0023]

As described above, according to the present invention, a work spindle capable of rotatably holding a work 3 for a twist end mill having a plurality of cutting blades such as a spiral blade 3a formed in the axial direction. A grinding tool, such as a grindstone 9 having two and capable of grinding the cutting edge of the grinding line 3c of the cutting blade of the work 3 is movable relative to the work 3 in the axial direction of the work spindle 2. And a work contact detecting means such as a touch sensor 16 for detecting a contact state of the work 3 with the cutting blade, the work contact detecting means being provided so as to be movable relative to the work spindle 2 in the axial direction of the work spindle 2. Synchronous movement means such as a rest base 6 and a grindstone head 7 that can move the grinding tool and the workpiece contact detection means in the axial direction of the workpiece spindle 2 relative to the workpiece spindle 2 in synchronization is provided. Output from contact detection means Since the work spindle rotation control means for controlling the rotation of the work spindle 2 based on the signal S1 such as the signal determination unit 22, the work spindle rotation control unit 25, and the first motor 5 is provided, the cutting edge is ground. When doing
While the work contact detection means is moved synchronously with the grinding tool by the synchronous movement means, the work spindle rotation drive control means is caused to perform the work spindle 2 based on the signal S1 output to the work contact detection means and representing the contact state with the cutting blade. The rotation of can be controlled. Then, when the cutting edge of the cutting blade is spirally ground in the grinding device for the twist end mill such as the grinder 1, the cutting blade and the grinding tool are brought into contact with each other in a state of being in contact with the cutting blade of the work 3. The grinding is performed by moving the work spindle. In this case, in the present invention, the work spindle 2 is rotated so that the grinding tool and the work contact detecting means that are moving synchronously are always in contact with the cutting blade of the work 3. It is possible to perform grinding while controlling. As a result, the work 3 is ground while being rotated so that the cutting edge portion of the cutting blade always maintains the state where the cutting edge of the work 3 is accurately and accurately in contact with the grinding surface of the grinding tool. As a result, the grinding tool does not come off from the cutting edge of the cutting blade of the work 3, and each cutting edge of each of the plurality of cutting blades of the work 3 is ground so as to always have a uniform shape. Therefore, according to the present invention, it is not necessary to read the shape of the cutting edge prior to grinding as in so-called profile machining, and the machining can be immediately started by bringing the workpiece contact detection means and the grinding tool into contact with the cutting blade. The edge of the cutting blade can be uniformly ground in a simple and short time. That is, the time required for grinding the twist end mill can be shortened. Further, according to the present invention, since a skilled worker's skill is not required to perform the grinding of the cutting edge, the finished state of grinding may be uneven due to the difference in skill of the operator. Instead, a precise twist end mill that always produces a uniform cutting edge is machined and finished. In the twist end mill grinding device according to the present invention, since it is not necessary to read the shape of the cutting edge as described above, the memory required for storing the shape of the cutting edge is not necessary, and the machine cost is low accordingly. is there. Therefore, it is possible to precisely grind the twist end mill at low cost.

[Brief description of drawings]

FIG. 1 is a front view showing an example of a twist end mill during a grinding process using the present invention.

FIG. 2 is a view on arrow II in FIG.

FIG. 3 is a plan view showing a line shape to be processed in the twist end mill shown in FIG.

FIG. 4 is a block diagram showing a control system of the twisting end mill processing apparatus according to the present invention.

FIG. 5 is a flowchart showing a grinding process of the twisting end mill grinding device according to the present invention.

[Explanation of symbols]

1 ... Grinding device for grinder (grinding machine) 2 ... Work spindle 3 ... Work 3a ... Cutting blade (blade) 3c ... Blade edge (ground line) 6 ... Synchronous moving means (rest base) 7 ... … Synchronous movement means (grinding stone head) 9 …… Grinding tool (grinding stone) 16 …… Workpiece contact detecting means (touch sensor) 5 …… Workpiece spindle rotation drive control means (first motor) 22 …… Workpiece spindle rotation drive control means (Signal determination section) 25 ... Work spindle rotation drive control means (work axis rotation control section)

Claims (1)

[Claims] 1. A grinding machine having a work spindle capable of rotatably holding a work for a twist end mill having a plurality of spiral cutting blades formed in the axial direction, and capable of grinding the cutting edge of the cutting blade of the work. A tool is provided in the axial direction of the work spindle so as to be relatively movable with respect to the workpiece, and work contact detection means for detecting a contact state with the cutting blade of the work is provided in the axial direction of the work spindle. Synchronous movement means is provided so as to be movable relative to the work spindle, and the grinding tool and the work contact detection means can be synchronously moved relative to the work spindle in the axial direction of the work spindle. A twist end mill grinding device, comprising a work spindle rotation drive control means for controlling the rotation of the work spindle based on a signal output from the work contact detection means.