JPH0560719U - Throw-away tip - Google Patents

Abstract

(57) [Summary] [Structure] In a throw-away tip having a substantially quadrangular upper surface 2, a pair of side ridges facing each other among the peripheral surfaces 4, 5 connected to the side ridges 7, 8 of the upper surface 2. Part 7, 7
The pair of peripheral surfaces 4 and 4 which are continuous with each other are made into a concave peripheral surface which is recessed inward toward the center of the side ridge portion 7 by the plurality of flat surface portions 4A, 4B and 4C which are continuous along the side ridge portion 7. .. Further, a main cutting edge 9 is formed on the other pair of side ridges 8, 8 on the upper surface 2. [Effect] By using such a tip 1 as an outer peripheral blade of a throw-away type cutting tool, which side is used when cutting is performed while moving the cutting tool toward the tip end side or the base end side in the axial direction thereof. It is possible to provide a throw-away type cutting tool capable of providing a clearance to these peripheral surfaces 4 and 4 to prevent contact with a work material even when the cutting tool is moved to a lower position, thereby reducing cutting resistance. It will be possible.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a throw-away tip (hereinafter referred to as a tip) used for a throw-away type cutting tool.

[0002]

[Prior Art]

 As such a throw-away type cutting tool, for example, a throw-away type end mill (hereinafter abbreviated as end mill) as described in Japanese Utility Model Laid-Open No. 62-168210 is known. This end mill has a chip discharge groove spirally formed on the outer periphery of the tool body, and a plurality of chip mounting seats are formed along the chip discharge groove on the rear side of the chip discharge groove in the tool rotation direction. A plate-like chip is detachably attached to these chip mounting seats with a clamp screw to form a chip row.

This chip has a substantially square upper and lower surface and four peripheral surfaces continuous with the side ridges of the upper and lower surfaces, and a pair of side ridges facing each other on the upper surface has cutting edges. It is formed so that its upper surface faces the outer peripheral side of the tool, one of the cutting edges is oriented in the tool rotation direction, and these cutting edges have a positive or negative axial rake angle. It is attached to the seat. In the end mill of this publication, the pitch of the chips adjacent to each other in each insert row is narrowed to the minimum, and each insert mounting seat is slightly shifted in the peripheral direction of the tool, so that By continuing the rotation trajectory in the tool axis direction, an outer peripheral blade having a length exceeding the cutting edge length of a single insert is formed in each spiral groove.

[0004]

[Problems to be solved by the device]

 By the way, in cutting with such an end mill, in addition to the case where the tool body of the end mill is moved only in the direction perpendicular to the tool axis to perform cutting, in addition to this, the tool body is moved to the tip side in the tool axis direction or It may be moved to the base end side for cutting. In such a case, for example, when cutting while moving the tool main body to the tip side in the tool axis direction, if the peripheral surface of the tip peripheral surface arranged on the tool front side is not allowed The peripheral surface may cause unnecessary contact with the work material, resulting in an increase in cutting resistance. On the contrary, when moving the tool body to the base end side in the tool axis direction, if the clearance is not given to the peripheral surface of the insert located on the tool base end side, the contact with the work material is similarly performed. It may occur.

However, in the tip having the above-mentioned structure, the peripheral surface of the tip arranged on the tool tip side and the peripheral surface of the tip arranged on the tool base end side are formed to be parallel to each other. If a relief is given to the peripheral surface, it cannot be provided to the other peripheral surface. Therefore, the above tip can provide only an end mill that can move the tool body to either the tip side or the base end side in the tool axial direction, that is, the end mill can move in the tool axial direction. It was impossible to move the tool body to either side of the tool for smooth cutting, and as a result, the versatility of the tool had to be naturally limited.

[0006]

[Means for Solving the Problems]

 The present invention has been made in order to solve such a problem, and provides a throw-away tip having a substantially rectangular upper and lower surfaces and four peripheral surfaces continuous with the side ridges of the upper and lower surfaces. Of the peripheral surfaces, a pair of peripheral surfaces that are continuous with a pair of side edge portions of the upper surface that face each other face the inside of the chip along the pair of side edge portions toward the central portion of the side edge portions. And a cutting edge is formed on at least one of the other pair of side ridges on the upper surface.

[0007]

[Action]

 In a chip with such a configuration, the above-mentioned concave peripheral surface is arranged at both ends across the cutting edge, so that the top angle of the corner of the top surface of the chip is set to the acute angle side. Become. Therefore, when such a tip is used in a cutting tool such as the above-mentioned end mill, the clearance for the cutting edge is provided both on the peripheral surface of the tip arranged on the tool tip side and on the peripheral surface of the tip end side. Therefore, it is possible to avoid unnecessary contact with the work material even when cutting is performed while moving the tool body to either side in the axial direction.

[0008]

【Example】

 1 to 4 show an embodiment of the present invention. In these figures, a chip 1 is a flat plate made of a hard material such as cemented carbide, and has a substantially parallelogrammatic upper surface 2, a lower surface 3 arranged in parallel with the upper surface 2, and upper and lower surfaces 2 thereof. , 3, and four peripheral surfaces 4, 4, 5, 5 arranged around the periphery of In addition, a through hole 6 that opens to the upper and lower surfaces 2 and 3 is formed in the center of the chip 1 in plan view. Of these four peripheral surfaces 4, 4, 5, 5, the pair of peripheral surfaces 4, 4 connected to the pair of side edge portions 7, 7 of the upper surface 2 facing each other are respectively the side edge portions 7, 7 is formed of three flat surface portions 4A, 4B, 4C that are continuous in the direction in which they are formed. These flat portions 4A, 4B, 4C are all so-called negative surfaces that are perpendicular to the upper and lower surfaces 2, 3, and therefore, as shown in FIG. The intersection angle α with the lower surfaces 2 and 3 is set to 90 °.

As shown in FIG. 1, of these plane portions, first, the plane portion 4A is formed so as to incline toward the inside of the chip 1 from one end of the side edge portion 7 toward the central portion side. Further, the flat surface portion 4B connected to the flat surface portion 4A is formed so as to incline more greatly than the flat surface portion 4A toward the center of the side ridge portion 7 and toward the inside of the chip 1. Further, the flat surface portion 4C connected to the flat surface portion 4B is formed so as to be inclined toward the outside of the chip 1 as it goes away from the central portion side toward the other end of the side ridge portion 7. That is, the flat portions 4A and 4B are bent and connected in a convex shape, and the flat portions 4B and 4C are bent and connected in a concave shape, and the central portion of the entire peripheral surface 4 is chipped. 1 is a concave peripheral surface that is concave inward. Therefore, by this, the center portion of the pair of side ridges 7, 7 connected to the concave peripheral surfaces 4, 4 is also formed in a concave shape in which the side ridges 7, 7 are recessed in the direction in which they face each other. The intersection ridge line between the peripheral surface 4 and the lower surface 3 is provided with a flat chamfer. Further, a curved chamfer is applied to the ridge line portion where the flat surface portion 4A and the upper surface 2 intersect.

On the other hand, the other pair of peripheral surfaces 5 and 5 connected to the other pair of side edge portions 8 and 8 of the upper surface 2 are each formed of one flat surface that intersects the upper surface 2 at an acute angle. This is a so-called page. Therefore, the peripheral surface 5 has a clearance angle β as shown in FIG. The clearance angle β is set to 11 ° in this embodiment. By adopting the above-mentioned configuration for the peripheral surfaces 4 and 5, the top surface 2 of the chip 1 has an acute apex angle at all corners C1, C1, C2 and C2 as shown in FIG. Is formed as. Further, regarding the apex angle of these corner portions, the apex angle θ1 of the corner portion C1 of the portion where the plane portion 4A and the peripheral surface 5 intersect is the portion where the plane portion 4C and the peripheral surface 5 intersect. Is set to be larger than the apex angle .theta.2 of the corner portion C2. In the present embodiment, these apex angles .theta.1 and .theta.2 are set to 80.degree. And 76.degree., Respectively. Further, the main cutting edges 9 and 9 of the tip 1 are formed on the other pair of side edge portions 8 and 8 of the upper surface 2, that is, on the intersecting edge portions of the upper surface 2 and the peripheral surfaces 5 and 5, respectively. There is. A sub-cutting edge 10 continuous with the main cutting edge 9 is formed at the ridge line portion where the flat surface portion 4A of the peripheral surface 4 and the peripheral surface 5 intersect.

In the tip 1 having such a configuration, the peripheral surfaces 4 and 4 arranged at both ends of the main cutting edge 9 are sandwiched into concave peripheral surfaces, and the corner portions C1 and C2 located at the both ends are formed. Since all of them are set on the acute angle side, by using such a tip 1 as an outer peripheral blade of a cutting tool such as an end mill, the tip 1 is arranged on the peripheral surface and the base end side which are arranged on the tool tip side. It is possible to give relief to both of the placed peripheral surfaces.

For example, FIGS. 5 to 7 show a tip portion of an end mill in which the tip 1 of the above-described embodiment is mounted on the tip of the tool of the tip row to form a tip outer peripheral blade tip. In these drawings, the tool main body 11 is formed of steel or the like and has a substantially cylindrical shape, and a spiral chip discharge groove 12 that is twisted around the tool axis O at a negative twist angle is formed on the outer peripheral portion of the tool main body 11. 4 are formed at equal intervals in the circumferential direction, and chip mounting seats 13 that open to the outer peripheral surface of the tool body 11 and the chip discharge groove 12 are formed on the rear side in the tool rotation direction. Of the chip discharge grooves 12, ... A pair of chip discharge grooves 12A, 12A located symmetrically with respect to the tool axis O has a tip mounting seat 13A located at the tip of the tool. The chip 1 is detachably attached by a clamp screw 14. Further, a bottom blade tip 15 is attached to the tip mounting seat 13B located at the tip of the tool of the other pair of chip discharge grooves 12B, 12B. Further, outer peripheral blade tips 16 ... Are mounted on the other chip mounting seats 13 ... Excluding these tip mounting seats 13A and 13B, and these tip outer peripheral blade tips 1 and outer peripheral blade tips 16 ... By the blade tip 15 and the outer peripheral blade tip 16, a chip row extending from the tip of the tool body 11 toward the tool base end is formed for each chip discharge groove 12.

Here, the tip mounting seat 13 A on which the tip outer peripheral blade tip 1 is mounted is provided with a wall surface 13 a facing the tool tip side, and this wall surface 13 a is the concave peripheral surface 4 of the tip outer peripheral blade tip 1. It is formed in a mountain shape that bulges toward the tool tip side when viewed from the outer peripheral side of the tool so as to engage with the concave portion formed by the flat portions 4B and 4C in the central portion. Further, on the tool tip side of the tip mounting seat 13A, an outer peripheral convex portion 17 protruding from the bottom surface of the tip mounting seat 13A toward the outer peripheral side of the tool is integrally formed on the tool body 11. The wall surface 17a of the outer peripheral convex portion 17 facing the tool base end side is engaged with the concave portion of the central portion of the concave peripheral surface 4 of the tip outer peripheral blade tip 1 in the same manner as the wall surface 13a. It is formed in a mountain shape that bulges toward the base end side of the tool.

In this end mill, the tip outer peripheral blade tip 1 has the upper surface 2 directed toward the outer peripheral side of the tool, and one of the two main cutting edges 9, 1 is rotated by the tool mounting seat 13A having such a configuration. One of the two concave peripheral surfaces 4 and 4 is engaged with the outer peripheral convex portion 21 toward the tool tip side while the other concave peripheral surface 4 is directed toward the tool base end side in a state of being directed forward in the direction. It is seated against the wall surface 13a. Further, in this state, the main cutting edge 9 is provided with a positive axial rake angle, and the sub cutting edge 10 connected to the main cutting edge 9 is projected toward the tool tip side rather than the tip surface of the tool body 11. It is a part of the bottom blade of the end mill.

On the other hand, as the bottom blade tip 15 mounted on the other pair of tip mounting seats 13B, 13B at the tip of the tool, the tip having the same shape and size as the tip outer peripheral blade tip 1 is used in this end mill. .. Further, a tip projection 18 is formed on the outer peripheral side of the tip mounting seat 13B so as to project toward the tip of the tool. The bottom blade tip 15 has its upper surface 2 directed toward the tool tip side, one main cutting edge 9 directed forward in the tool rotation direction, and one concave peripheral surface 4 directed toward the tool outer peripheral side toward the tip convex portion 18. It is engaged and seated on the chip mounting seat 13B, and is fixed by the clamp screw 14.

Further, the outer peripheral blade tip 16 to be mounted on the tip mounting seat 13 other than the tip mounting seats 13A and 13B at the tip of these tools has a substantially equilateral triangular upper surface 18 in this end mill, and the upper surface 18 of the upper surface 18. A positive type chip having three peripheral surfaces 19 disposed around the peripheral surface. The upper surface 18 is directed toward the outer peripheral side of the tool and one peripheral surface 19 is directed forward in the tool rotation direction. A cutting edge 20 formed on a ridge line intersecting with the surface 19 is seated so as to face the chip discharge groove 12. Further, a cutout surface 21 is formed at three corners C3 ... At which the peripheral surfaces 19 of the outer peripheral blade tip 16 intersect with each other, and a cutting edge 20 is formed at a ridgeline intersection between the cutout surface 21 and the upper surface 18. Corner blades 22 intersecting at 120 ° are formed. The two outer peripheral blade chips 16, 16 adjacent to each other in one chip row are such that one outer peripheral blade chip 16 located on the tool tip side is more than the other outer peripheral blade chip 16 located on the tool base end side. It is arranged so as to be shifted to the rear side in the tool rotation direction. Further, in these outer peripheral blade tips 16, 16, the notch surface 21 located on the tool base end side of the cutting blade 20 of one outer peripheral blade tip 16 is formed on the peripheral surface 19 of the other outer peripheral blade tip 16 facing the tool tip side. The corner blades 22 are also arranged close to each other in the direction of the tool axis O so as to face each other. Therefore, the corner blade 22 located on the tool base end side of one outer peripheral blade tip 16 has the upper surface of the other outer peripheral blade tip 16. It is arranged so as to face the edge portion of the tool 18 located on the tip side of the tool substantially in parallel.

In the end mill having such a structure, the peripheral surface 4 of the tip outer peripheral blade tip 1 facing the tool tip side and the peripheral surface 4 facing the tool base end side are both concave peripheral surfaces. The relief for the main cutting edge 9 is provided on both the peripheral surfaces 4. Therefore, by using the tip 1 of the above-described embodiment, there are a case where the cutting is performed while moving the tool body 11 toward the tip side in the tool axis O direction and a case where the cutting is performed while moving the tool body 11 toward the base end side in the tool axis O direction. In either case, it is possible to avoid the peripheral surface 4 of the tip 1 from coming into contact with the work material, and it is possible to reduce the cutting resistance. That is, according to the tip 1 having the above-described structure, it is possible to smoothly perform the cutting process while moving the tool body 11 to the tip end side or the base end side in the axis O direction with one end mill, which is highly versatile. It becomes possible to provide an end mill.

Further, in the tip 1 of the above-mentioned embodiment, the concave peripheral surfaces 4, 4 arranged at both ends of the main cutting edge 9 are respectively composed of three flat surface portions 4A, 4B, 4C. 4, 4 and the main cutting edge 9 intersect, that is, the apex angle of each corner C1, C2 of the upper surface 2 of the tip is the apex angle θ1 of the corner C1 where the flat surface 4A intersects the main cutting edge 9 Is set to be larger than the apex angle θ2 of the other corner portion C2. However, this corner C1 is also a corner where the sub cutting edge 10 connected to the main cutting edge 9 intersects. Therefore, according to the tip 1 of this embodiment, in the tip outer peripheral edge tip, a part of the bottom edge is formed. It is possible to set the angle of the leading edge of the auxiliary cutting edge 10 that is configured, and the angle of the edge of the secondary cutting edge 10 that configures a part of the outer peripheral blade in the bottom blade tip 15 to be large. As a result, there is an advantage that the strength of the cutting edge can be improved and a chip or the like can be prevented.

In this embodiment, the flat portions 4A, 4B, 4C forming the pair of concave peripheral surfaces 4, 4 of the chip 1 are negative surfaces, and the other pair of peripheral surfaces 5, 5 are positive surfaces. However, conversely, the concave peripheral surfaces 4 and 4 may be positive surfaces and the peripheral surfaces 5 and 5 may be negative surfaces. Furthermore, both the peripheral surfaces 4 and 5 may be negative surfaces or positive surfaces.

By the way, in the above end mill, the tip 1 of this embodiment is used only for the tip tip outer peripheral blade tip of the tip row of the tips mounted on the outer circumference of the tool. This is because the effect of the contact of the cutting tip with the work surface and the peripheral surface is most likely to occur when the cutting is performed while moving the tool body 11 toward the base end side in the tool axis O direction. That is, of the tips mounted on the outer circumference of the tool, the outer peripheral blade tips 16 other than this tip outer peripheral blade tip have the wall surface of the tip mounting seat on the tool tip side and the base end side, so that the tool axis O direction It is held relatively firmly even when a load is applied to it. Since the tip of the outer peripheral blade tip has a wall surface of the tip mounting seat on the tool base end side, when the tool body 11 is moved toward the tip side in the tool axis O direction, the tip is firmly fixed. Although held, the tip 1 is fixed and held only by the clamp screw 14 when the tool body 11 is moved to the base end side in the tool axis O direction to perform so-called pulling up. If a load is generated on the tip end side in the tool axis O direction due to the contact of the chip in such a state with the work material, an excessive load is imposed on the clamp screw 14.

On the other hand, in the above end mill, the tip 1 of the embodiment of the present invention is used in the tip outer peripheral blade tip which is most affected by the contact with the work material as described above, and as described above, Even in the case of pulling up, the peripheral surface 4 located on the tool base end side of the chip 1 can be provided as a concave peripheral surface to provide relief. Therefore, it is possible to prevent unnecessary contact between the peripheral surface 4 and the work material, reduce the cutting resistance acting on the chip, and reduce the load on the clamp screw 14. In addition to this, in the above end mill, the outer peripheral convex portion 17 is formed at the tip of the tool main body 11, and the tip outer peripheral blade tip 1 engages the peripheral surface 4 on the tool tip side with the outer peripheral convex portion 17. Since it is mounted as described above, the load on the clamp screw 14 can be further reduced. Further, in the above end mill, the tip 1 of this embodiment is also used for the bottom blade tip 15, and the concave peripheral surface 4 facing the outer peripheral side of the tool is attached by engaging the tip convex portion 18. Therefore, even if the bottom blade tip 15 is subjected to a load acting on the outer peripheral side of the tool, it is possible to securely hold the tip similarly to the tip outer peripheral blade tip and reduce the load on the clamp screw 14.

Further, in the above end mill, the outer peripheral blade tip 16 other than the tip outer peripheral blade tip 1 is formed with a corner blade 22 at its corner C3, and the outer peripheral blade tips 16 and 16 adjacent to each other have one tool base. The corner blade 22 on the end side is arranged so as to face the side edge portion of the other upper surface 18 on the tool tip side substantially in parallel. For this reason, it becomes possible to arrange the outer peripheral edge tips 16 in the tool axis O direction closer to each other, and it is possible to set a large amount of overlapping of the cutting edges 20 of these outer peripheral edge tips 16 in the tool axis O direction. The advantages that the load acting on each outer peripheral blade tip 16 can be reduced, and especially chipping of the tip caused by such a load acting on the corner C3 can be prevented beforehand. Can also be obtained.

In the above end mill, the outer peripheral blade tips 16 and the bottom blade tip 15 are attached to the rear side in the axial direction of the tool in a row, and the outer peripheral blade tips 16 are attached to each other along a plurality of chips along the chip discharge groove 12. Although the chip row is formed as described above, for example, as shown in FIGS. 8 and 9, each chip discharge groove 12 may be provided with only one tip outer peripheral blade tip 1 or bottom blade tip 15. However, in FIGS. 8 and 9, reference numeral 31 denotes a tool body formed in a truncated cone shape whose tip portion 31A expands in diameter toward the tip end side in the tool axis O direction, and other portions are shown in FIGS. The same parts as those of the end mill shown in FIG.

[0024]

[Effect of the device]

 As described above, according to the present invention, the peripheral surfaces arranged at both ends of the cutting edge are concave peripheral surfaces, which allows the tool body to be moved while moving the tool body to either side of its axial direction. However, it is possible to provide a throw-away type cutting tool that can prevent these materials from coming into contact with the work material by giving relief to these peripheral surfaces. As a result, it is possible to reduce the cutting resistance at the time of such cutting processing, and it is possible to perform stable processing.

[Brief description of drawings]

FIG. 1 is a plan view from the upper surface 2 side of a chip 1 showing an embodiment of the present invention.

FIG. 2 is a side view of the chip 1 shown in FIG. 1 as viewed in the X direction.

FIG. 3 is a side view of the chip 1 shown in FIG. 1 as viewed in the Y direction.

FIG. 4 is a ZZ sectional view of the chip 1 shown in FIG.

5 is an enlarged side view of a tip portion of an end mill using the tip 1 shown in FIG.

FIG. 6 is a front view of the end mill shown in FIG.

FIG. 7 is an outer peripheral development view of the end mill shown in FIG.

8 is a side view showing another example of the end mill using the tip 1 shown in FIG. 1. FIG.

FIG. 9 is a front view of the end mill shown in FIG. 8 viewed from the tool tip side.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 tip (tip outer peripheral blade tip) 2 upper surface 4 concave peripheral surface 4A, 4B, 4C flat surface portion constituting the concave peripheral surface 4 peripheral surface 7, 8 side edge portion of upper surface 9 main cutting edge 10 sub cutting edge 11, 31 End mill tool body 12, 12A, 12B Chip discharge groove 13, 13A, 13B Chip mounting seat 14 Clamp screw 15 Bottom blade tip 16 Peripheral blade tip 17 Peripheral convex portion 18 Tip convex portion 20 Peripheral blade tip 16 cutting blade 22 Perimeter Corners of the blade tip C1, C2 Corners of the tip 1 Corner angle of top corner 2 of the top surface 2 of the tip 1 Tip 1 Corner angle of top corner 2 of the top surface 2 of the tip 1 Tip angle O of the tool O axis

Claims (3)

[Scope of utility model registration request] 1. A throw-away tip having a substantially quadrangular upper and lower surface and four peripheral surfaces continuous with side ridges of the upper and lower surfaces, wherein the upper surface of the peripheral surface is opposed to each other. The pair of peripheral surfaces connected to the pair of side ridges is a concave peripheral surface that is recessed inward of the chip toward the center of the side ridges along the pair of side ridges, and at least the other upper surface. A throw-away tip having a main cutting edge formed on one of a pair of side ridges. 2. A sub-cutting edge is formed on one of the intersecting ridgelines connecting the main cutting edges among the ridges intersecting the peripheral surfaces, and among the corners where the side ridges of the upper surface intersect. The apex angle of a corner portion located at one end of the main cutting edge and intersecting with the sub cutting edge is set to be larger than the apex angle of a corner portion located at the other end of the main cutting edge. The throw-away tip according to claim 1. 3. The throw-away tip according to claim 1, wherein the concave peripheral surface is composed of a plurality of surfaces that are bent and continuous in a direction along the pair of side ridges.