JP2558887Y2 - Indexable milling tools - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a throw-away milling tool, such as a screw-on-clamp type cutter or end mill, to which a throw-away tip is attached with a screw.

[0002]

2. Description of the Related Art Conventionally, there is an end mill shown in FIG. 4 and FIG. FIG. 4 is a side view of the end portion of the end mill, and FIG. 5 is a sectional view taken along line AA of FIG. In the drawing, a groove 3 for mounting a throw-away tip 2 is formed in the outer periphery of a tip end portion of a tool body 1 of an end mill so as to be cut out in a substantially fan shape in cross section (see FIG. 5). On the surface of the groove 3 facing the tool body rotation direction,
The seating surface 4 of the indexable insert 2 is formed along the axial direction, and the surface in the rotational direction forms a chip discharge surface 5, and is formed to be longer than the seating surface 4 from the tip of the tool body 1 toward the base end. (See FIG. 4).

[0003] The seating surface 4 of the throw-away tip 2 forms a plane slightly inclined from the base end to the tip end with respect to the axis in a side view. A screw hole 6 for fixing the throw-away tip is formed in the seating surface 4 toward the rear in the rotation direction of the tool body. Also, a throw away tip 2
Is provided with a stepped screw hole 7 corresponding to the screw hole 6 at the time of mounting, and the screw 8 is screwed into the screw hole 6 through the stepped screw hole 7 of the chip 2 so that the throw away The tip 2 is firmly fixed to the seating surface 4 of the tool body. Further, on the rear side in the rotation direction of the screw hole 6 of the tool body 1, a recessed hole 9 is drilled from the outer peripheral surface of the screw hole 6 in the direction opposite to the seating surface 4 in the extension line direction of the screw hole 6. (In the direction of arrow a), and communicates with the screw hole 6. Generally, if the tip of the screw hole 6 is formed by sealing in a dead end shape, dust and scum easily accumulate on the bottom and the like, and if it is dyed black, it tends to be clogged, which is not preferable because the screw 8 is screwed tightly. For this reason, a through hole 9 communicating with the screw hole 6 is formed at the tip of the screw hole 6 so that dust, scum and the like do not accumulate inside. The recessed hole 9 is provided on the seating surface 4 with respect to the screw hole 6.
In the side view shown in FIG. 4, a boundary surface 9 a with the outer peripheral surface of a portion communicating with the screw hole 6 becomes flat, and corner portions 9 b are provided at both ends thereof in the side view shown in FIG. 4. , 9b
Is formed. The portion between the seating surface 4 of the tool main body 1 and the tip end surface of the recess 9 is plate-shaped (see FIG. 5). Further, at a corner located on the base end side of the seating surface 4 and extending in a direction substantially perpendicular to the axis, a chip seat recess 10 is provided in the extending direction of the corner.

[0004]

[Problem to be solved by the invention]
Is formed in this way, cracks c may enter or be lost in the direction of the seating surface 4 from the corners 9b of the recessed hole 9 due to the notch effect. For this reason, the plate-shaped tool body having the boundary surface 9a of the through hole 9 and the seating surface 4 is easily deformed or broken, and the screw 8 is bent at the time of fixing the chip, and the chip 2 cannot be mounted. There is a disadvantage that. In addition, such a through hole 9
Is generally cut by a processing end mill, but when drilling the recess 9, FIG.
In the substantially circular cross section of the tool main body orthogonal to the axis as shown in FIG. 1, the recess 9 is machined while relatively moving the machining end mill in the longitudinal direction of the screw hole 6 formed in the direction of the chord. Therefore, when the diameter of the tool body is large, such as a milling cutter, the length of the end mill must be considerably large so that the chuck portion holding the machining end mill does not contact the outer peripheral surface of the tool body. There is a disadvantage in processing that it is not necessary.

The present invention has been made in view of the above circumstances and provides a throw-away type rolling tool in which machining of a through hole is easy and cracks, breakage, and the like are hardly generated in the through hole portion of the tool body. With the goal.

[0006]

SUMMARY OF THE INVENTION A throw-away type milling tool according to the present invention is provided with a screw hole for fixing a throw-away tip on a seating surface of a groove provided on an outer peripheral portion of a tool body having a substantially circular cross section. In a throw-away type milling tool formed by fixing a throw-away tip to a seating surface by screwing a screw into this screw hole via a throw-away tip, a screw hole is formed. In the direction intersecting the screw hole from the outer peripheral surface at the rear side in the tool rotation direction, a round recess hole communicating with the screw hole is provided.

[0007]

[Action] Since the through holes are provided in the direction intersecting with the screw holes, it is easy to drill the through holes with a machining end mill or the like, and furthermore, with the seating surface of the portion having the seating surface of the tool body. Since the facing pit holes have a circular shape, the strength is high without forming corners or the like.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS. 1 and 2. The same reference numerals are used for the same parts or members as those in the above-mentioned prior art, and the description is omitted. FIG. 1 is a side view of the tip of the end mill, and FIG. 2 is a sectional view taken along line BB of FIG. In the figure, in the tool body 1 of the end mill, a round shaped sunk hole 12 is provided at the tip end of the screw hole 6 of the seating surface 4 in a direction crossing the screw hole 6 from the outer peripheral surface of the tool body 1. For this reason, the screw hole 6 communicates with the recessed hole 12 at the tip. This hole 12
1 is to be formed in the same direction as the chip seat recessed hole 10 in the side view of the tip end portion of the tool main body 1 shown in FIG. Therefore, the surface 12a of the recessed hole 12 facing the seating surface 4 formed in the tool body 1
Has a circular shape. For this reason, a corner portion that easily causes the notch effect is not formed in the surface portion facing the seating surface 4.

Further, since the recessed hole 12 is formed as described above, when the recessed hole 12 is formed by a machining end mill or the like, a sectional view taken along a line BB of FIG. 1 shown in FIG.
Although the tool body 1 has a substantially circular shape, it can be machined by relatively moving the machining end mill in a direction substantially perpendicular to the longitudinal direction of the screw hole 6 (direction of arrow b). Even if the diameter of the main body 1 is relatively large, the drill of the processing end mill having a short length can be easily formed without hindering the chuck of the processing end mill.

As described above, in the end mill according to the present embodiment, since the corners and the like are not formed on the surface 12a facing the seating portion 4 of the recessed hole 12 communicating with the chip fixing screw hole 6, cracks due to the notch effect are generated. No chipping or the like occurs, and the strength of the tool body from the seating portion 4 to the recessed hole 12 can be increased. Also, in the drilling of the through hole 12 by a processing end mill or the like, since the processing direction is the same direction as the direction of the chip seat through hole 10, the work can be performed in the same setup, and the processing is easy. Reduction of processing time and reduction of processing cost can be achieved. Moreover,
Screw holes 6 in a circular cross section orthogonal to the axial direction of the tool body 1
Since the pits 12 can be machined in a direction intersecting with the longitudinal direction, the length of the machining end mill may be short, and machining is easy.

Next, another embodiment of the present invention will be described with reference to FIG. FIG. 3 is a front view of the front milling machine. In the figure, a chip discharge groove 15 and a seating surface 4 of a throw-away tip 2 located rearward in the direction of rotation of the chip discharge groove 15 are formed at a predetermined interval on an outer peripheral portion of a front end of a tool body 14 of the front milling cutter. Each seating surface 4 is provided with a screw hole 6 for a screw for fixing the chip toward the rear side in the rotation direction. Behind that, a screw hole 6 is formed from the outer peripheral surface of the tool body.
A round shaped through hole 16 is provided in a direction intersecting with the screw hole 6 and communicates with the tip of the screw hole 6. In the drawing, the burrow 16 is omitted except for one. In the case of the present embodiment, the circular tool body has a large diameter in a cross section in a direction perpendicular to the axis of the tool body 14, but the through hole 16 is formed in a direction intersecting the longitudinal direction of the screw hole 6. In addition, the machining of the through hole 16 is easy.

In the above-described embodiment, the end mill and the face mill have been described. However, the present invention is not limited to this, and it goes without saying that the present invention can be applied to other indexable milling tools.

[0013]

As described above, the indexable rolling tool according to the present invention has a threaded hole communicating with the screw hole in a direction intersecting the screw hole from the outer peripheral surface behind the screw hole in the tool rotation direction. Since it is provided, no corner or the like is formed in a portion facing the seating portion of the through hole communicating with the screw hole for chip fixing, no crack or breakage due to the notch effect occurs, and from the seating portion to the through hole. The strength of the tool body can be increased. Also, in the case of drilling a through hole with a machining end mill or the like, since the processing direction is the same direction as the chip seat through hole direction, the work can be performed in the same setup, and the processing is easy and the processing time is short. Reduction and processing cost can be achieved. In addition, since it is possible to machine a through hole in the direction crossing the longitudinal direction of the screw hole in a circular cross section perpendicular to the axial direction of the tool body, the length up to the chuck of the machining end mill may be short, and machining is easy. It is.

[Brief description of the drawings]

FIG. 1 is a front side view of an end mill according to a first embodiment of the present invention.

FIG. 2 is a sectional view taken along line BB of the end mill shown in FIG.

FIG. 3 is a front side view of a face mill according to a second embodiment of the present invention;

FIG. 4 is a front end side view of a conventional end mill.

FIG. 5 is a sectional view taken along line AA of the end mill shown in FIG. 4;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Tool main body 2 Indexable insert 3 Groove 4 Seating surface 6 Screw hole 12, 16

Claims (1)

(57) [Scope of request for utility model registration] A screw hole for fixing a throw-away tip is drilled substantially rearward in the rotational direction of a tool on a seating surface of a groove provided on an outer peripheral portion of a substantially circular cross section of a tool body. In a throw-away type milling tool formed by screwing a screw through a throw-away tip to fix the throw-away tip, in a direction intersecting the screw hole from the outer peripheral surface in the tool rotation direction rear of the screw hole, A throw-away type milling tool, wherein a round shaped through hole communicating with the screw hole is provided.