JP2002187009A - Cutter for drilling operation - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cutter for drilling operation capable of operating drilling with high efficiency and coaxiality without requiring reversal of a material, and also capable of dispensing with a setting-up work. SOLUTION: The cutter is used for drilling a through-hole consisting of a plurality of stepped holes from one end to the other end of a metal material in its longitudinal direction. The cutter has a main body part 2 which is at least longer than a hole length of a minimum diameter hole to be operated, and is provided with a tip 5 for cutting at the end surface of the main body part, a supporting guide pad 6 on an outer peripheral surface for smoothing sliding contact with the inner surface of the hole with the minimum diameter, a base part 3 of a larger diameter than the main body part at the base end of the main body part 2, and a supporting guide pad 7 on the peripheral surface of the base part for smoothing sliding contact with the inner surface of the hole with the second minimum diameter.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cutter used for drilling a through hole formed of a plurality of stepped holes from one end of a metal material in the longitudinal direction to the other end.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 3, one end has a small diameter and the other end has a large diameter, and a stepped non-through hole 12 extends from the other end to the middle of one end. The BTA (Boring & Trepaning Association) uses a drilling process to penetrate the non-through holes 12 of the metal material 11 formed in the direction.
It stands for: if done in deep hole processing machine), as shown in FIG. 4, first, the drilling of the inner diameter d ₁ so that this coaxial direction from one end to the blind small holes 12a of the blind holes 12 Done, material 1
1 is a through hole in which one end and the other end communicate. Then performs replacement BTA type, material 11 is inverted such that the one end and the other end to reverse relative to BTA, drilling of the inner diameter d ₂ by using the small hole 12a from the other end thereafter Processing, and from the same side, drilling processing of the inner diameter d _{3 in} the same way,
The through-hole 13 is formed of a plurality of stepped holes 13a, 13b, 13c having a smaller diameter sequentially from one end to the other end in the length direction of the material 11. At the time of this processing, cutters for the respective inner diameters are prepared and replaced each time. In FIG. 4, reference numeral 15 denotes a cutter for the inner diameter d ₂ , which is attached to the tip of the boring bar 17 of the BTA 16. 18 is B
The rotating face plate constituting the TA 16 is used to hold one end of the material 11 and rotate the material.

In the case of the above-described drilling, the material 11 has to be turned over when the material 11 is drilled from the inner diameter d ₁ to the inner diameter d ₂ . . That is, if the drilling is performed without inversion, the drilling is performed in the order of the inner diameter d ₂ → the inner diameter d _{1. In} this case, the inner diameter d ₁ of the cutter used for the drilling is used. I can not support stably utilizing the pores of d _2, coaxiality of the holes of the hole and the inner diameter d ₁ the inner diameter d ₂ there is a risk that can not be maintained. Therefore, it is necessary to first invert the inside diameter d ₁ as described above and then invert the material 11. In addition, setup work was also required by reversing the material 11.

[0004]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned conventional problems, and enables high-efficiency and high-coaxial drilling without the need to reverse the material.
An object of the present invention is to provide a cutter for drilling that does not require a setup operation.

[0005]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention relates to a drilling process for drilling a through-hole consisting of a plurality of stepped holes from one end to the other end in the longitudinal direction of a metal material. A cutter used having at least a body longer than the length of the smallest diameter hole to be machined,
A cutting tip is provided on a distal end surface of the main body, a support guide pad is provided on an outer peripheral surface of the main body portion so as to be in sliding contact with an inner surface of a hole having a minimum diameter, and a main body is provided at a base end of the main body portion. A base having a larger diameter than the base portion is provided, and a support guide pad is provided on the outer peripheral surface of the base so as to slidably contact the inner surface of the hole having the smallest diameter and the inner surface of the next larger hole.

[0006]

An embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a front view showing an entire cutter for drilling. Reference numeral 1 denotes a cutter, which comprises a main body 2 and a base 3 having a larger diameter. Outer diameter D ₁ of the base portion 3 is formed in substantially the same diameter as the inner diameter d ₂ of the hole 13b. Body 2 of slightly larger diameter on the tip side, but from the base 3 has a small-diameter tip portion 2a, the outer diameter D ₂ of the distal end portion 2a is formed on substantially the same diameter as the inner diameter d ₁ of the holes 13a I have. The length L ₁ of the main body portion 2 is longer than the length L ₃ of the hole 13a, the length L ₂ of the base 3 has become about one substantially half of the length L ₁ main body 2. A cutting tip 5 is provided on the tip end surface of the main body 2.

A hole 13 is formed in a half of the outer peripheral surface of the main body 2 on the front end side.
A plurality of support guide pads 6 are provided at equal intervals in the circumferential direction to make smooth contact with the inner surface of a. The guide pad 6 is fitted in a recess formed on the outer peripheral surface of the main body 2 so that its surface slightly protrudes from the outer peripheral surface of the main body 2, and is attached with screws. When connecting the surface of the guide pad 6 was only slightly protruding as the so as to draw a perfect circle, the diameter of the perfect circle is adapted to the inner diameter d ₁ and the same diameter of the hole 13a. Also, a plurality of similar support guide pads 7 are provided at equal intervals in the circumferential direction at the front end side half of the outer peripheral surface of the base portion 3 so as to slide in contact with the inner surface of the hole 13b for smoothing. The guide pad 7 is fitted in a recess formed in the outer peripheral surface so that its surface slightly protrudes from the outer peripheral surface of the base 3 and is attached by screws 8. Also in this case, when the surfaces of the guide pads 7 which are slightly protruded are connected so as to draw a perfect circle, the diameter of the perfect circle becomes the inner diameter d of the hole 13b.
It has the same diameter as ₂ .

The operation will be described with reference to FIG. material
While holding one end of 11 with the face plate 18 and the other end of BTA16
Hold with. When the rotating face plate 18 is rotated in this state, the material
11 rotates and the'll advance the boring bar 17 fitted with a cutter 15 in the distal end portion, the hole 13b of the inner diameter d ₂ which corresponds to the diameter of the cutter 15 is formed over a predetermined length during the rotation . Next, the cutter 1 is attached to the tip of the boring bar 17 instead of the cutter 15, and the boring bar 17 is similarly advanced. Then, the hole 13a of the inner diameter d ₁ which corresponds to the outer diameter D ₂ of the front end portion 2a of the main body portion 2 by cutting with the chip 5 of the cutter 1 is over a predetermined length, are formed through to the distal end surface. Next, another cutter is attached to the tip of the boring bar 17 in place of the cutter 1, and the boring bar 17 is similarly advanced. Then, the hole 13c of the inner diameter d ₃ which corresponds to the outer diameter of the cutter is formed over a predetermined length.

The processing of the hole 13a by the cutter 1 is performed using the hole 13b of the first pass through which the base 3 passes as a guide. In addition, during this processing, the guide pad 6 attached to the distal end portion 2a advances while sliding on the inner surface of the hole 13a to smooth the inner surface of the hole, and the guide pad 7 attached to the base portion 3 It advances while sliding on the inner surface to smooth the inner surface of the hole. The guide pad 7 has a hole 13b.
Since the main body 2 is firmly supported by being in sliding contact with the inner surface of the shaft, the processing can be performed with stable support without the shaft core being loosened. Therefore, the coaxiality is not deviated, the high coaxiality can be maintained, and the setup work conventionally required is unnecessary. Also, as described above, this cutter 1
If the material 11 is used, there is no need to invert the material 11 as in the related art.

The cutter 1 described in the above embodiment is merely a preferred embodiment, and it is needless to say that the specific structure and shape can be arbitrarily changed and modified upon implementation.

[0011]

Since the present invention has the above-described structure, it is possible to perform high-efficiency, high-coaxiality drilling without the necessity of reversing the material, and to eliminate the need for setup work. There is.

[Brief description of the drawings]

FIG. 1 is an overall front view of a drilling cutter showing an embodiment of the present invention.

FIG. 2 is a drawing showing a step of drilling the same as above.

FIG. 3 is a drawing showing an example of a material before processing.

FIG. 4 is a view showing a conventional drilling process.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cutter 2 Main part 2a Tip part 3 Base 5 Cutting tip 6, 7 Supporting guide pad 8 Screw 11 Metal material 12 Non-through hole 13 Through hole 13a, 13b, 13c Stepped hole 15 Cutter 16 BTA 17 Boring bar 18 Face plate

Claims (1)

[Claims] 1. A cutter used for drilling a through hole comprising a plurality of stepped holes from one end side to the other end side in the longitudinal direction of a metal material, wherein the cutter has at least a minimum diameter to be machined. A supporting guide pad having a main body portion longer than the length of the hole, a cutting tip provided on the tip end surface of the main body portion, and an outer peripheral surface for making smooth contact with the inner surface of the hole having the smallest diameter. A support guide pad provided at a base end of the main body portion, the base portion having a larger diameter than the main body portion; A cutter for drilling, characterized in that a cutter is provided.