JPS6048208A - Annular perforating tool - Google Patents

Abstract

PURPOSE:To easily discharge chips without clogging a garret by reducing cutting resistance per one blade and also reducing the chips into finer particles by means of providing the cutting blades on the bottom part of the tool main body with steps arranged in radial direction. CONSTITUTION:An annular perforating tool capable of perforating a deep hole is provided with a key groove 3 as well as a screw hole 5 on the top of the cylindrical tool main body 1, a plurality of twisted grooves 7 on the outer wall and cutting blades 9 on the bottom. A plurality of these blades 9 are arranged at intervals in the circumferential direction and a plurality of steps a1-a3 are formed in radial direction of main body 1 and respective steps a1-a3 are formed in tapered faces. Then, when a hole is perforated with this tool, cutting resistance is reduced on each blade by dispersing the resistance over each step a1-a3 and the chips are also dispersed away from clogging the garret 7 and so easily discharged.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an annular drilling tool capable of drilling deep holes.

In general, when drilling annular holes, it is necessary to make it easy to spin out the chips in order to achieve a smooth machined surface and a high feed rate. A groove called a flute is also known. However, since the glue powder is usually formed in a continuous curled manner, it becomes entangled in the grooves 1 and 1, causing clogging, and cutting resistance. There was a problem in which the radial depth of the gullet increased, resulting in a chipped edge ('□I).Therefore, a solution 'b was proposed in which the depth of the gullet was increased in the radial direction, but in that case, the side surface of the cutter was thin and The problem arises that the strength becomes weaker.

This invention was made in order to solve such conventional problems, and by providing a step in the radial direction on the cutting blade at the lower end of the tool body, it reduces the cutting resistance per cut and also reduces the amount of chips. By dividing the gullet into small pieces, the chips are easily discharged without clogging the gullet 1, and the purpose is to create an annular hole that allows for smooth deep hole machining.

Hereinafter, one embodiment shown in the figure will be explained in detail. FIG. 1 is a perspective view of an embodiment of the present invention. Cylindrical 2 [Topping body 1
A keyway 3 and a screw hole 5 are installed at one end, a plurality of twisted grooves 7 are provided at the outer peripheral wall, and a cutting blade 9 is installed at the lower end.
is provided.

These cutting blades 9 (as shown in FIG. 2, a plurality of cutting blades are provided spaced apart in the circumferential direction). As shown in FIGS. A plurality of steps are provided in the radial direction of the step al, a2 and a3, and each step is
I+"2+"3 is tapered. Further, as detailed in FIG. 3, each stage al, a2 and a2. There is also a step between a3 and b2 in the circumferential direction. Furthermore, each stage alla2. a3 tip C+ + 02,
C3 also has taper α1. α2. α3 is taken.

When performing drilling work with this annular drilling tool, the apex of the 81st stage performs the scribing action, and cutting begins from the 81st stage and continues with the a2 and 83rd stages. Also, 81 steps, 82 steps, 8
Since there are steps tll and b2 between the 2nd stage and the 83rd stage, the chips from a + Fi, the 82nd stage Nyorori powder, and the 83rd stage Nyorori powder come out completely separated. In this way, each stage al.

The cutting resistance is dispersed between a2 and a3, so the cutting resistance acting on each cut is small, and the chips are dispersed, making it possible to create a galette @7.
This makes it difficult to get stuck inside. Roughly each step a1. a2.
Since a3 is tapered in the axial direction, the coefficient of friction between the blade part during cutting and the target to be cut becomes small, and the I? I'm so excited to hear that i-send is now available.

Since this invention has the configuration described in the claims,
- The cutting resistance that acts on the blade is small, and - the cutting chips that act on the blade are divided into shards and whirlpools. + Easy to put out 1 no 1 without +, smooth hole IJ 7+
lI, -r can be realized.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of an embodiment of the present invention, FIG. 2 is a bottom view of the same, FIG. 3 is an enlarged view of section A in FIG. 2, and FIG. 1 is an enlarged vertical cross-sectional view of the same. '1... Tool book IA 7... Groove 9... Cutting blade special π1 Applicant: 11 Koneji Cut and Saw Co., Ltd.

Claims (2)

[Claims] (1) Create multiple grooves on the outer peripheral wall of the cylindrical tool body. 1
11. An annular drilling tool comprising: a plurality of cutting blades spaced apart from each other in the circumferential direction at the lower end thereof, and a step provided on each cutting blade along the radial direction of the tool body. (2) The annular drilling tool according to claim 1, wherein each of the cutting blades is inclined in the radial direction and has a step.