JPH1133815A - Thrust machining tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform stable machining of high efficiency without impairing the machining surface accuracy. SOLUTION: A tip 8 whose contour assumes approx. a circuit disc is installed at the forefront of a tool body 1 in such a way that it is directed in the axial direction O of the tool body 1 with the circular surface 11 used as a rake face and the cutting edge 12 formed at the peripheral edge of the circular surface 11 is protruded over the whole circumference toward the peripheral side of the tool body 1, and the tool body 1 is fed in the axial direction O along the wall surface of the work to be machined, and thus the wall surface is machined by the cutting edge 12.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a punching tool used for processing, for example, a vertical wall surface (upright surface) of a mold.

[0002]

2. Description of the Related Art Conventionally, when cutting a mold or the like, a solid end mill is often used as a tool for machining a deep hole or a wall surface of a large mold or the like. When cutting with a solid end mill, if the vertical distance of the vertical surface to be machined increases, the distance from the holding part of the solid end mill held on the spindle (spindle) of the machine tool to the tip of the cutting edge, that is, the protrusion amount, also increases In this state, the vertical surface is cut while the cross feed is performed, and finishing is performed. Therefore, chatter vibration is easily generated, and the surface accuracy of the processed surface is deteriorated.
In addition, there is a disadvantage that the solid end mill bends due to the cutting resistance at the time of traverse feed and the machined surface is inclined.In this way, the cutting state is unstable, so it is not possible to perform upright machining by unmanned operation, It was necessary for an operator to constantly monitor the cutting state and make corrections to the processing at any time.

[0003] In order to solve such a problem, a plurality of polygonal flat chips are mounted on the outer periphery of the tip of the tool body which is rotated around the axis, and the cutting edges of the chips are on the inner circumferential side of the tool body. Using a thrusting tool whose rake face is oriented in the direction of tool rotation so that the cutting edge protrudes toward the outer circumference of the tool body so that the corner portion of the cutting edge protrudes toward the outer circumference of the tool body. While moving the tool body in the axial direction, the work material is cut by the cutting blade to form a wall surface on the work material, that is, the upright surface. Attempts have been made to form a wall surface having a certain width on a work material by sequentially repeating it. However, according to such a piercing tool, the upright machining of the above-described die or the like can be performed by the vertical feed cutting of the tool main body, so that the protrusion amount becomes larger than that of the lateral feed cutting by the end mill. This also has the advantage that chattering vibration is less likely to occur, and that there is little occurrence of bending during transverse feed.

[0004]

However, in such a butting tool, the tool body rotates around the axis and is sent out in the axial direction while cutting the work material to perform the machining. When the feed amount in the axial direction of the cutting edge is increased, the feed amount per one cutting edge is also increased, and the accuracy of the machined surface may be impaired. On the other hand, if it is attempted to increase the rotation speed of the tool body in order to prevent the feed amount per tooth from increasing in this way, the cutting speed also increases, causing damage to the cutting blade and vibration of the tool body. As a result, there is a possibility that the cutting may become unstable, and as a result, it is difficult to increase the feed amount with the punching tool having the above configuration, and there is naturally a limit in improving the processing efficiency.
In the case of a piercing tool in which the rake face of the insert faces the tool rotation direction, the main component of the cutting force acting on the tool moves the tool body and the spindle of the machine tool in a direction perpendicular to its axis. Since it acts as a bending component to bend, there is a problem that the stability of cutting is further impaired.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide a punching tool capable of performing highly efficient and stable machining without impairing the machining surface accuracy.

[0006]

In order to solve the above-mentioned problems and to achieve the above object, the present invention provides a tip having a substantially disk shape on a tip portion of a tool body and a circular surface formed on the tip. Along with being oriented in the axial direction of the tool main body as a rake face, a cutting blade formed on the outer peripheral edge of the circular surface is attached so as to protrude to the outer peripheral side of the tool main body over the entire circumference,
By feeding the tool body in the axial direction along the wall surface of the work material, the wall surface is cut by the cutting blade.

[0007] However, in the punching tool configured as described above, the outer disk-shaped chip is mounted with its rake face directed in the axial direction of the tool main body, and the tool main body is fed in the axial direction. As a result, the wall surface of the workpiece is cut by the cutting edge of the rake face of the chip, so that a desired machining surface accuracy can be obtained regardless of the rotation of the tool body during machining. Therefore, it is possible to prevent the feed amount from being limited or generating vibration due to the rotation of the tool main body, and to increase the feed amount while maintaining the stability of the cutting, thereby improving the machining efficiency. As well as
The cutting speed itself is lower than in the case of cutting by rotation of the tool body, and since the insert is disk-shaped and the cutting edge strength is high, damage such as chipping of the cutting edge can be prevented.
When cutting is performed by feeding the tool body in the axial direction, the main component of the cutting resistance acts as a thrust component along the axis of the tool body or the spindle of the machine tool. And the bending component can be suppressed, so that more stable cutting can be promoted.

Here, with the butting tool having the above-described structure, the wall surface of the work material can be cut regardless of the rotation of the tool body as described above. Therefore, for example, only the feed in the axial direction is performed without rotating the tool body. Although it is also possible to perform cutting, the tip is attached to the tool body with its central axis being coaxial with the axis, and the tool body is fed in the axial direction while rotating around the axis to perform cutting. Is performed, the cutting edge formed on the tip can be used evenly for cutting, and the wear of the tip can be made uniform. Further, by performing cutting while rotating the tool body in this manner, an effect is obtained in which the actual cutting edge angle is sharpened and sharpness is improved as compared with a case where the tool body is not rotated.

On the other hand, since only the outer peripheral portion where the cutting edge is formed is used for machining among the above-mentioned inserts,
If this chip is formed in an annular shape, the chip manufacturing cost can be reduced as compared with a case where the chip is formed in a solid disk shape. When the tip is formed in an annular shape as described above, if a fitting portion that can be fitted to the inner peripheral portion of the tip is formed at the tip of the tool body, the fitting portion is formed in an annular shape. Since the chip is positioned by being fitted to the inner peripheral portion of the chip, especially when the tool body is rotated as described above, it is possible to accurately align the center axis of the chip with the axis of the tool body. In addition, it is possible to improve the mounting rigidity of the chip. Furthermore, on the front and back of the chip, a pair of the circular surfaces each having the cutting blade are formed, and by reciprocating the tool body in the axial direction, using the pair of circular surface cutting blades. In addition, the work material can be cut in both the reciprocating strokes of the feed of the tool main body, and the substantial cutting ratio can be substantially doubled so that the machining time can be reduced by half.

[0010]

1 and 2 show a first embodiment of the present invention.
1 shows an embodiment of the present invention. In the present embodiment, a mounting hole 2 for mounting the tool main body 1 to a spindle (not shown) of a machine tool is formed in a central portion of the substantially cylindrical tool main body 1 along an axis O thereof. Mounting hole 2
A keyway 3 is formed on the rear end face of the tool body 1 so as to communicate with the keyhole. Then, the tool main body 1 has the set bolt 4 inserted into the mounting hole 2 with the key formed on the spindle front end fitted in the key groove 3 while the set bolt 4 is inserted into the tool main body. By being screwed into the spindle through the mounting hole 2 from the front end of the spindle 1, the spindle 1 is attached to the front end of the spindle, and is able to advance and retreat in the direction of the axis O as the spindle comes and goes.

The tip of the tool body 1 has the axis O
An annular fitting portion 5 whose inner peripheral portion communicates with the mounting hole 2 is formed so as to protrude toward the distal end side with the center as the center. An annular concave groove 6 opened to the outer peripheral side is provided. This groove 6
Is formed in a direction orthogonal to the axis O, and the tool body 1
An annular bottom surface 6A facing the distal end of the tool body 1 and a cylindrical surface formed in a direction perpendicular to the bottom surface 6A and facing the outer peripheral side of the tool body 1 and centered on an axis O serving as the outer peripheral surface of the fitting portion 5 A plurality of (three in this embodiment) mounting screw holes 7 are formed in the bottom surface 6A in the circumferential direction on the same circumference centered on the axis O. At regular intervals,
Further, they are formed in parallel with the axis O.

A chip 8 made of a hard material such as a cemented carbide is attached to the groove 6.
The tip 8 is a ring-shaped positive tip whose inner peripheral portion 8 </ b> A has a size that can be fitted to the fitting portion 5, and its outer diameter is slightly larger than the outer diameter of the tool body 1. Also, the thickness is slightly larger than the height of the fitting portion 5 in the direction of the axis O from the bottom surface 6A of the concave groove 6. Further, the chip 8 is formed with the same number of chip mounting holes 9 as the mounting screw holes 7 so as to penetrate the chip 8 in the thickness direction thereof.
A is fitted to the fitting portion 5 at the tip of the tool body 1,
Clamp screws 10 inserted into these chip mounting holes 9.
Are screwed into the mounting screw holes 7 so as to be detachably mounted in the concave grooves 6 of the tool body 1.

Further, when the tip 8 is mounted on the tool body 1 in this manner, the circular surface 11 of the tip 8 facing the tip side of the tool body 1 has an outer peripheral edge 11A having an inner peripheral edge 11B. The outer periphery of the outer peripheral edge 11A, that is, the outer peripheral edge of the circular surface 11 has a circumferential shape centered on the axis O. A cutting edge 12 is formed. Therefore, the cutting blade 12 projects outward from the outer peripheral surface of the tool body 1 over the entire circumference. Further, the outer peripheral edge 11A of the circular surface 11 of the tip 8 is formed so as to gradually retreat toward the rear end in the direction of the axis O as it goes toward the inner peripheral side of the tool main body 1. The rake face is provided with the rake angle α, and the peripheral surface 13 of the tip 8 is formed so as to gradually decrease in diameter toward the inner peripheral side of the tool main body 1 toward the rear end side in the axis O direction, The flank has a clearance angle β given to the cutting edge 12. The inner peripheral edge 11 </ b> B of the circular surface 11 is formed in a direction orthogonal to the axis O, and is formed so as to be flush with the distal end surface of the fitting portion 5.

In the punching tool constructed as described above, the tool main body 1 is attached to the tip of the spindle as described above with its axis O being coaxial with the axis of the spindle of the machine tool, as shown in FIG. As described above, the axis O is made parallel to the wall surface S of the workpiece W, and is sent out along the wall surface S in the feed direction F toward the front end side in the axis O direction.
The wall S is cut along the feed direction F by the cutting blade 12. Therefore, regardless of the rotation of the tool body 1, the cutting of the wall surface S is performed by the feed in the feed direction F. Thus, as in the case of the conventional punching tool, in order to obtain a predetermined machining surface accuracy, the tool body is cut. The rotation does not limit the feed amount, or the rotation of the tool body does not cause chattering vibrations, and cutting becomes unstable.
In addition, since the feed amount of the tool body 1 is not limited as described above, the cutting conditions can be set relatively freely, and chattering vibration due to a decrease in the cutting speed, as will be described later, can be prevented. Can be avoided.

For this reason, according to the butting tool having the above-described configuration, even if the feed amount of the tool body 1 in the feed direction F is increased, a desired machined surface accuracy can be obtained and vibration can be reliably prevented. As a result, stable cutting can be promoted, so that high-efficiency machining using the feed capability of the machine tool to its limit can be achieved. Incidentally, according to an experiment, when the thrusting tool of the present embodiment is used for finishing the wall surface S, the cutting D and the cutting width P (see FIG. 3) are equal to those of the above-mentioned conventional thrusting tool. Cutting with the maximum feed amount is possible, and when the thrusting tool of the present embodiment is used for rough machining of the wall surface S, the cutting depth D is equal to the conventional thrusting tool and the cutting width P is reduced. Thereby, it is also possible to cut with the maximum feed amount of the machine tool and obtain the same machining surface accuracy as the finish machining, that is, it is possible to obtain a desired machining surface in one rough machining process. .

Further, when the workpiece W is cut by feeding the tool body 1 in the direction of the axis O (feed direction F) as compared with the conventional case where the tool body is rotated and cut. As described above, even if the feed amount is increased to achieve high-efficiency machining, the cutting speed itself can be kept low. In addition, in the butting tool having the above-described configuration, the insert 8 has a disk shape as described above, and the circular surface 11 is a rake face, so that a sharp corner is formed on the cutting edge 12. Therefore, the strength of the cutting blade 12 itself is improved. Therefore, according to the piercing tool having the above configuration, even if the feed amount is increased for the high-efficiency machining, it is possible to prevent the cutting blade 12 from being damaged or the like, such as chipping, and to insert the chip. 8 can be extended. Conversely, if the life of the chip 8 is the same, the chip 8
The material of the cemented carbide such as the present embodiment or C
Even without using an expensive material such as BN, the chip 8 can be manufactured from an inexpensive material such as high-speed steel (high-speed tool steel), and the chip cost can be reduced.

Further, when cutting is performed by feeding the tool body 1 in this manner, the main component of the cutting resistance acting during machining acts in the feed direction F of the tool body 1, so that the tool body 1 And the thrust component along the axis O of the spindle and the axis of the spindle, and it is possible to prevent the main component from acting as a bending component as in the above-mentioned conventional pushing tool. By the way, according to the experiments, the ratio of the thrust component to the bending component in the cutting force acting during machining was about 0.1 in the conventional piercing tool, and the bending component was overwhelmingly large. On the other hand, in the present embodiment, this ratio was about 1.0, and the bending component and the thrust component were almost equal. However, the tool body 1 and the spindle of the machine tool have the highest rigidity in the thrust direction (the direction of the axis O). By receiving this, it is possible to achieve more stable cutting, and it is possible to promote more efficient machining.

Here, in the butting tool of the present embodiment,
The tip 8 is formed in an annular shape having an inner peripheral portion 8A. In the tip 8, a circular cutting edge 12 is formed on an outer peripheral edge of a circular face 10 which is a rake face. For this reason, for example, the chip 8 may be formed in a solid disk shape in which the inner peripheral portion 8A is not formed. However, since only the outer peripheral portion of the chip 8 on which the cutting edge 12 is formed is processed exclusively in the chip 8, for example, when the chip 8 is formed of a cemented carbide or the like. For example, tip 8
Increases the manufacturing cost. Therefore, in the present embodiment, by forming the tip 8 in an annular shape as described above, it is possible to provide a relatively inexpensive tip 8 even when the material is cemented carbide or CBN. .

Further, in the present embodiment, in accordance with the fact that the tip 8 is formed in an annular shape as described above, a fitting portion in which the inner peripheral portion 8A of the tip 8 can be fitted to the tip end of the tool body 1. The tip 8 is positioned in the radial direction of the tool body 1 by fitting the inner peripheral portion 8 </ b> A to the fitting portion 5 and attaching the tip 8. 8 can be mounted on the tool body 1 such that the center of the circumferential cutting edge 12 more accurately coincides with the axis O of the tool body 1. Moreover, since the inner peripheral portion 8A of the tip 8 is fitted into the fitting portion 5 of the tool body 1 in this manner, the rigidity of mounting the tip 8 on the tool body 1 can be increased. According to the butting tool, it is possible to further improve the processing accuracy. Furthermore, in the punching tool having the above-described configuration, since the tip 8 is mounted so that the entire periphery of the cutting edge 12 protrudes toward the outer peripheral side of the tool body 1, even if the cutting edge 12 is worn or the like, the tip 8 may be worn. In the case of re-grinding, the re-grinding can be performed while the tip 8 is mounted on the tool body 1, and the handling is easy, and the center of the newly formed cutting edge 12 by the re-grind Body 1
The advantage is also obtained that the axis O can be accurately matched with the axis O.

By the way, in the butting tool having the above structure,
As described above, the wall surface S of the workpiece W can be cut regardless of the rotation of the tool main body 1, and for example, the cutting can be performed only by feeding in the direction of the axis O without rotating the tool main body 1. However, in such a case, the circumferential cutting edge 1
2 is a part used for cutting, and if the cutting blade 12 is worn in this part, the tool body 1 is rotated by a predetermined angle, and cutting is performed by the cutting blade 12 part without wear. There is a cutting blade 12
When is used for cutting for each part, it is inevitable that the degree of wear varies in the entire circumferential direction of the cutting blade 12. Therefore, in order to prevent such variations from occurring, the tool body 1 is sent out in the direction of the axis O (feed direction F) while rotating the tool body 1 around the axis O at a certain number of rotations as shown by a broken line in FIG. It is also possible to perform cutting.

However, since the cutting is performed while rotating the tool body 1 while rotating the tool body 1, the circumferential cutting blade 12 is used evenly and uniformly over the entire circumference. And the situation where the life of the tip 8 is extremely shortened due to partial wear can be prevented. Further, by cutting the workpiece W by feeding it in the direction of the axis O while rotating the tool body 1 as described above, the work material W is cut by the cutting blade 12 moving forward in the feeding direction F, and Since the cutting edge 12 rotates in the circumferential direction, it is also cut, and the substantial cutting edge angle of the cutting edge 12 with respect to the workpiece W becomes sharper than the rake angle α. Therefore, the cutting resistance can be reduced and more stable cutting can be performed, and the improvement of the machining surface accuracy can be promoted.

In the present embodiment, the tip 8 is mounted on the tip of the tool body 1 with the circular surface 11 serving as a rake face facing the tip of the tool body 1. The leading end side in the direction is defined as a feed direction F, and the feed direction F
When the tool body 1 is sent out to the workpiece W
For example, on the contrary, the tip 8 is mounted so that the circular surface 11 serving as a rake face thereof faces the rear end side of the tool body 1, and the above-mentioned axis O of the tool body 1 is set. The rear end side in the direction may be the feed direction, and the wall surface S of the work material W may be cut when the tool body 1 retreats toward the rear end side in the axis O direction.

Further, as described above, the tool main body 1 is
In addition to cutting the work material W only when sending out to one side in the direction, the peripheral surface 13 of the chip 8 includes the axis O, for example, as in the second embodiment of the present invention shown in FIG. The cross-section is formed in a V-shape that opens to the outer peripheral side, and the cutting edges 12,
By forming 12 and reciprocating the tool body 1 in the direction of the axis O, the wall surface S of the workpiece W may be cut in both reciprocating movements of the tool body 1. In this case, By substantially doubling the substantial cutting ratio and halving the processing time, it is possible to promote more efficient processing. In the second embodiment shown in FIG. 4, the same parts as those in the first embodiment shown in FIGS. 1 and 2 are denoted by the same reference numerals, and description thereof is omitted.

[0024]

According to the present invention, regardless of the rotation of the tool body, the wall surface of the workpiece can be cut to a predetermined machining surface accuracy by feeding the tool body in the axial direction thereof. The feed amount is prevented from being restricted or the vibration is not caused by the rotation of the main body, and the feed amount is increased while performing stable cutting, so that high-efficiency machining can be performed. In addition, the cutting speed itself is reduced, and the cutting edge strength is high because the insert is disk-shaped, so that damage to the cutting edge can be prevented to extend the tool life and reduce costs. Further, since the bending component acting during cutting can be reduced, it is possible to promote more stable cutting.

[Brief description of the drawings]

FIG. 1 is a partially cutaway side view showing a first embodiment of the present invention.

FIG. 2 is a front view of the embodiment shown in FIG.

FIG. 3 shows a wall surface S of a work material W according to the embodiment shown in FIG.
It is a figure which shows the case where is processed.

FIG. 4 is a partially cutaway side view showing a second embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Tool main body 5 Fitting part 8 Throw-away tip (tip) 8A Inner peripheral part of throw-away tip 8 11 Circular surface (rake face) of throw-away tip 8 12 Cutting edge O Axis line of tool main body 1 F Feed of tool main body 1 Direction W Work material S Wall surface of work material W

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Masaaki Hasegawa 1528 Nakashinda, Yokoi, Kobe-cho, Yahachi-gun, Gifu Prefecture Inside of Gifu Works, Mitsubishi Materials Corporation (72) Inventor Kiyoaki Shibata, Yojii, Kobe-cho, Yahachi-gun, Gifu 1528 Nakashinda, Mitsubishi Materials Corporation Gifu Works (72) Inventor Naofumi Yamashita 1 Toyota Town, Toyota City, Aichi Prefecture Toyota Motor Corporation

Claims (4)

[Claims] At the tip of the tool body, a chip having a substantially disk shape is formed on the outer peripheral edge of the circular surface with the circular surface facing the axial direction of the tool body as a rake face. The cutting blade is attached so as to protrude to the outer peripheral side of the tool body over the entire circumference, and the tool body is fed in the axial direction along the wall surface of the work material, whereby A punching tool characterized by cutting the wall. 2. The chip is attached to the tool body with its center axis being coaxial with the axis, and the tool body is fed in the axial direction while being rotated about the axis. Item 6. The piercing tool according to Item 1. 3. The tool according to claim 2, wherein the tip is formed in an annular shape, and a fitting portion capable of fitting to an inner peripheral portion of the tip is formed at a tip end of the tool body. The piercing tool according to claim 1 or 2. 4. A pair of said circular surfaces each having said cutting edge are formed on the front and back of said tip, and said tool body is reciprocated in said axial direction. A thrusting tool according to any one of claims 1 to 3.