JPH0541622U - Radius ball end mill - Google Patents

Abstract

(57) [Summary] [Object] The present invention relates to a radius ball end mill, and provides an end mill that can be used for various purposes by using an oval-shaped throw-away tip that can be used for vertical feed, shoulder milling, etc. To aim. According to the present invention, a plurality of oval-shaped throw-away tips are used, and the arc cutting blades of the tips are used for cutting the R portion, and the linear cutting blades are used for the bottom blade and the outer peripheral blade as in the conventional case.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a radius-type throw-away type ball end mill.

[0002]

[Prior Art]

 Many radius ball end mills to which a throw-away tip having an arc cutting edge is attached have already been proposed and put into practical use. For relatively small-diameter one-way-away inserts, round inserts are used to improve the attachment strength and attachment accuracy of the insert while covering the dimensional margin of the attachment part. However, even if the end mill has a relatively large blade diameter and has a plurality of blades, it has been proposed to arrange a large number of round tips. However, round inserts have low mounting strength and are prone to chatter during cutting and the resulting chip damage, so further improvement in performance is expected.

[0003]

[Problems to be solved by the device]

 The purpose of the present invention is to provide a means for mounting strength and axial cutting, which are the drawbacks of radius type ball end mills that use round inserts, so that the chip has mounting strength and stable chip mounting accuracy. It is to provide a high performance throw away type radius ball end mill.

[0004]

[Means for solving the problem]

 In order to achieve the above-mentioned problems, the present invention has the following constituent features. That is, in the present invention, when the throw-away tip is attached to the tip seat, the tip mounting accuracy is stable because the reference surface for attachment to the tip seat wall surface is a straight side surface. As a matter of course, the tip seat wall surface can be easily processed because it is a straight flat surface. In addition, the rake face that is the upper surface of the insert is a convex curved surface, so the cutting edge length is longer than that of a flat rake surface, and the cutting amount per cutting blade unit length can be reduced, so stable cutting area without chattering etc. Can be extended to higher conditions.

A feature of the present invention is that the throw-away tip can commonly use a tip that forms the first bottom blade and a tip that cuts a second linear portion in the axial direction. Since the insert has a relatively long straight cutting edge, it has a cutting edge up to the shaft center line, and can also be used for vertical feed cutting. Also, the depth in the axial direction is as deep as the length of the straight cutting edge. it can.

[0006]

【Example】

 An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a front view of a throw-away type ball end mill according to the present invention, and FIG. 2 is a bottom view thereof. FIG. 3 is a front view showing another example of the present invention. 4 is a plan view of the throw-away tip incorporated in the proposed ball end mill, and FIG. 5 is a side view thereof.

In FIGS. 1 and 2, reference numeral 1 denotes a cylindrical tool body, a tip pocket portion 2 and a tip seat 3 are provided at the tip of the tool body. 4 and a throw-away tip having a straight side surface 5 as a cutting edge is attached by a set screw 6. The first tip 7 is attached at an angle of α degrees with respect to the normal to the axial direction, and the second tip 8 is attached at an angle of β degrees with respect to the axial direction. When increasing the mounting strength, it is more effective to use both setscrews and clamps. Further, FIG. 3 shows an example in which α is large.

As shown in FIGS. 4 and 5, the oval throw-away tip is connected to a pair of substantially 1/2 circular arc side surfaces 4 which are point-symmetrical with respect to the central mounting hole. It has a straight upper side surface 5, and each side surface is formed with a clearance angle so that the bottom surface is smaller than the rake surface. Further, cutting resistance can be reduced by forming a concave breaker on the outer peripheral portion of the rake face. Furthermore, the mounting mechanism of the tip will be described in detail with reference to FIG. Since the tip is attached so as to be applied in the direction of the intersection of the two tip seat wall surfaces, the tip can be stably and reliably fixed to the tip seat.

[0009]

[Effect of the device]

 The present invention relates to a throw-away type radius ball end mill, wherein the throw-away tip has an approximately 1/2 circular arc side surface at a position point-symmetrical with respect to the central mounting hole and a linear side surface continuous with the circular side surface. The first tip has a cutting edge on the side of the arc, and the straight side extending to the side of the arc extends to near the center of the axis of the tool body. The tip has a cutting edge on the side of the arc, and a straight cutting edge connected to the side of the arc is a cutting edge in the axial direction, so that the tip seat can be easily machined and the mounting accuracy of the tip is stable. Also, the contact length of the cutting edge is increased, and therefore a synergistic effect of these can provide a high-performance throw away type radius ball end mill.

[Brief description of drawings]

FIG. 1 is a front view of a throw-away type ball end mill according to the present invention.

FIG. 2 shows a bottom view of FIG.

FIG. 3 shows a front view of another embodiment of the present invention.

FIG. 4 is a plan view of a throw-away tip incorporated in the ball end mill of the present invention.

FIG. 5 shows a side view of FIG.

[Explanation of symbols]

 1 Tool body 2 Tip pocket 3 Tip seat 4 Arc side 5 Straight side 6 Set screw 7 First throw-away tip 8 Second throw-away tip α Angle of attachment of tip 7 Angle of attachment of tip 8

Claims (1)

[Scope of utility model registration request] 1. A plurality of throw-away tips are detachably fixed by set screws through a central mounting hole on the rake face of the tips in a tip seat provided at the tip of a cylindrical tool body. In the throw-away type radius ball end mill, the throw-away tip has an arc-shaped side surface of approximately 1/2 circle at a position point-symmetrical with respect to the central mounting hole, a straight side surface continuous with the arc-shaped side surface, and a flat bottom surface and a convex surface. The upper surface (rake surface) of the curved surface
Has a cutting edge on the side of the arc, and the straight side extending to the side of the arc extends to the vicinity of the axial center of the tool body to form a cutting edge. The second tip cuts on the side of the arc. A radius ball end mill having a blade edge and a straight cutting edge connected to the side surface of the circular arc as an axial cutting edge.