JPH09207012A - Drilling spot facing cutter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform rapid and simple cutting of a hole having a spot facing and to ensure the spot facing with a specified depth. SOLUTION: A drill 17 is supported at a holder 11, a rotary body 21 having drilling tips 23 is fitted in the outer periphery of a drill 17. The rotary body 2 is movable forward and backward axially of the drill and rotated integrally with the drill 17. The rotary body 21 is energized in an advancing direction through the force of a spring 19. Even when the upper surface position of a work 25 is not specified, the rotary body 21 is moved and the height of the upper surface position thereof is absorbed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a perforated counterbore cutter for simultaneously forming perforations and counterbores in a work such as steel.

[0002]

2. Description of the Related Art For example, as shown in FIG. 5, a counterbore 28 is formed at an end of a hole 26 in order to pass a sinking tack 27 or the like through the hole 26. Conventionally, in order to form the counterbore 28, after boring using a drilling machine or the like, the end of the boring is counterbored by a tool different from the drilling machine.

[0003]

However, the depth of the spot facing is not constant in the past, and since it is necessary to perform double machining, not only is it troublesome to machine, but also a drilling machine and spot facing. Two types of processing machines were required.

The present invention has been made in order to solve the above problems, and the purpose thereof is to perform drilling and counter boring in a single drilling operation and to suppress vibration during machining. Therefore, it is an object of the present invention to provide a perforated counterbore cutter capable of achieving high efficiency and high precision machining.

[0005]

In order to achieve the above object, in the invention described in claim 1, a drill for drilling and a drill for arranging the drill at an outer peripheral position thereof and advancing in the axial direction of the drill, A rotating body that can be retracted and can rotate integrally with the drill, a counterbore blade supported on the rotating body so as to be located on the outer periphery of the drill, and bias the rotating body in the forward direction. It is equipped with a spring.

According to a second aspect of the present invention, in the first aspect, there are a plurality of blades, and the rotation surfaces of the blades are at different positions. According to a third aspect of the invention, in the second aspect, the number of blades is two.

According to the invention described in claim 4, in any one of claims 1 to 3, a part of the rotating surface is wrapped. Therefore, when the work is drilled with the drill, the counterbore is located at the outer peripheral position of the drill and the counterbore processing is performed simultaneously with the drilling.

Further, since the rotating surfaces of the blades are located at different positions, the cutting amount per blade does not become excessive.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to FIGS. As shown in FIGS. 1 and 2, the holder 11 rotatably supports a rotary shaft 12 through a bearing 13 therein, and one end of the rotary shaft 12 is connected to a spindle (not shown) of a drilling machine or the like. The connecting portion 14 is formed. The cylindrical accommodating portion 15 is fixed to the tip of the holder 11, and the sleeve 16 is accommodated therein.

The drill 17 is fixed to the tip of the rotary shaft 12 and is supported by the sleeve 16 via a bearing 18. The spring 19 includes a large number of ring-shaped leaf springs and is housed in the housing portion 15. The stopper 20 is accommodated at the tip of the accommodating portion 15 so as to be able to advance and retract along the axial direction of the drill, and is urged by the spring 19 in the advancing direction. The protruding position of the stopper 20 is regulated by the contact between the protrusion 20a and the protrusion 15a. Recess 2
0b are formed at three positions at the tip of the stopper 20, and chips are discharged from the recess 20b to the outside.

The rotating body 21 is fitted on the outer circumference of the drill 17, is supported by the stopper 20 via a bearing 22, and is moved integrally with the stopper 20 in the axial direction. The pair of drilling tips 24 are fixed to the tip of the drill 17.
The pair of counterbore tips 23 are separated from the drilling tips 24 and fixed to the rotating body 21, and are located on the outer periphery of the drill 17. The rotating body 21 has a pair of protrusions 21a on the inner periphery thereof.
Comes into contact with the pair of concave lands 17a of the drill 17 and is rotated integrally with the drill 17.

As shown in FIG. 4, the counterbore tip 23 is formed.
Has a substantially triangular shape, and each side has a blade 23a.
Are formed. The blades 23a involved in the cutting are located on different rotating surfaces, which are partially overlapped. The blades 23a on the three sides involved in cutting are rearranged due to wear or the like.

Therefore, as shown in FIG. 3, when the rotary shaft 12 is rotated, the drill 17 and the rotary body 21 are integrally rotated. Therefore, the work 25 is drilled by the drilling tip 24 at the tip of the drill 17, and when the drilling reaches a certain depth, the counterbore tip 23 moves the work 25.
And a chamfered spot face is cut. in this case,
As shown in FIG. 5 , the work 25 is curved,
Even if the upper surface position of the work 25 is not constant, the position of the rotating body 21 supporting the spot facing chip 23 is displaced,
It is possible to carry out counter boring with a certain depth. That is, when the upper surface position of the work 25 is high, the rotating body 21 resists the spring force of the spring 19 in accordance with the height of the work 25 and the rotating body 21 moves to the housing portion 15.
Retreat and immerse inside. Therefore, the height of the upper surface of the work 25 is absorbed, and the spot facing amount becomes constant.

Further, during the counter boring process, since the counter boring tips 23 have different rotary surfaces on which a part of the counter boring tips 23 wrap, the counter boring tips 23 carry the cutting of a portion of a width narrower than the entire cutting width. . Therefore, the cutting resistance per one spot facing chip 23 does not increase, and the chips generated by cutting become fine.

As described above, this embodiment has at least the following advantages. (1) Since counter boring and boring are performed almost at the same time, it is possible to easily machine a hole having a spot facing in a short time. (2) Since it is possible to perform punching and counter boring with the same tool, only one processing machine is required. (3) As described above, regardless of the shape of the work 25, it is possible to always carry out counterbore cutting with the same depth. (4) Since the structure for preventing relative rotation of the counterbore tip 23 with respect to the drill 17 uses the land 17a of the drill 17 and the convex portion 21a of the rotating body 21, a separate component is not required and the structure is simple. become. (5) Since the rotating surfaces of the spot facing tips 23 are partially overlapped and different, even if the cutting width is large, each of the tips 23 carries a different cutting area and the amount of cutting per chip 23 is small. . For this reason, the cutting resistance per chip is reduced, and the spot facing chip 23 and the rotating body 2 supporting it.
The load of 1 is reduced, and problems such as insufficient rigidity do not occur.
Therefore, vibration during cutting can be suppressed, and high precision machining and high efficiency machining can be achieved. Moreover, since the amount of cutting per chip is small, the chips generated by cutting are fine. For this reason, chips can be discharged smoothly, high rotation can be performed, and high efficiency machining can be contributed.

The present invention can be embodied even with the following modifications. (A) Change the number of blades of the spot facing tip 23 and the punching tip 24 to two or more. Even with such a configuration, the same effect as that of the above-described embodiment can be enjoyed. (B) The mounting angle of the spot facing chip 23 can be changed. According to this structure, the spot facing 28 corresponding to the inclined surface of the sunken tack 27 can be formed. (C) The counterbore tip 23 should be changed to another shape such as a square shape having blades on four sides and a pentagonal shape having blades on five sides. If the number of blades is increased, the life of the spot facing chip 23 can be extended.

Further, the technical idea understood from the above embodiment will be described below. (1) A boring seat in which the spot facing tip 23 is supported by the rotating body 21, the rotating body 21 is fitted on the outer periphery of the drill 17, and the convex portion 21a of the rotating body 21 is brought into contact with the land 17a of the drill 17. Boring cutter. With this structure, the structure is simplified without increasing the number of parts.

[0018]

Since the present invention is constructed as described above, it has the following effects. According to the first aspect of the present invention, it is possible to easily cut a counterbore having a constant depth, and to perform both boring and counterbore with a single processing machine.

According to the second to fourth aspects, vibration during cutting can be suppressed to achieve high efficiency machining and high precision machining.

[Brief description of drawings]

FIG. 1 is a cutaway front view of a main part of a perforated spot facing cutter according to an embodiment of the present invention.

FIG. 2 is a bottom view of the perforated spot facing cutter.

FIG. 3 is a cutaway front view of essential parts when using a punched spot facing cutter.

FIG. 4 is a sectional view showing a work.

FIG. 5 is an enlarged sectional view showing a cutting portion.

[Explanation of symbols]

17 ... drill, 19 ... spring, 20 ... stopper, 2
3 ... Counterbore tip, 23a ... Blade, 24 ... Perforated tip.

Claims (4)

[Claims] 1. A drill for drilling, a rotating body which is arranged at an outer peripheral position of the drill, is movable forward and backward in the axial direction of the drill, and is rotatable integrally with the drill, and is positioned on the outer periphery of the drill. In addition, a perforated counterbore cutter including a counterbore blade supported on the rotating body, and a spring for urging the rotating body in a forward direction. 2. The perforated counterbore cutter according to claim 1, wherein there are a plurality of blades, and the rotation surfaces of the blades are at different positions. 3. The perforated counterbore cutter according to claim 1, wherein the blade has two blades. 4. A part of the rotating surface is wrapped.
A perforated spot facing cutter according to any one of 3 to 3.