JP2528627B2 - Drilling tool - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drilling tool consisting of a rod and a blade such as a drill or a tap attached to the tip of the rod, which is particularly suitable for highly accurate drilling work and is easy to manufacture. is there.

[0002]

2. Description of the Related Art For example, in the case of manufacturing a car body of a train or the like, when a decorative plate is attached to the inside of an outer plate, a screw hole is formed by a drill or a tap in a mounting bracket portion integrally formed inside the outer plate.

However, in the case where the mounting bracket portion is located on the ceiling or in the inaccessible back portion, workability may be poor or impossible with a drill or tap having a short base portion.

In such a case, a screw hole can be formed in the mounting bracket portion by using a drill or tap with a long base, but a blade such as a drill or tap with a long base is more expensive than one with a short base. Therefore, it is expensive to use as a consumable item.

Therefore, from the viewpoint of improving the workability and reducing the cost of consumables, etc., at some drilling work sites, conventionally, as shown in FIG. 5, the bar material 1 is brazed to the blade 2 having a short base. The attached one is used as a drilling tool.

[0006]

However, in such a conventional drilling tool, since the blade 2 and the bar 1 are joined by brazing as described above, high heat during brazing is required. As a result, not only the strength of the bar and drill around the joint may decrease, but also warpage may occur.
Not suitable for high precision drilling work.

Further, since the conventional drilling tool requires the axial centering of the blade 2 and the bar 1 at the time of brazing, it cannot be easily made by anyone, and only an expert can manufacture it. Further, even an expert is difficult to align the axes while performing brazing.

In some cases, it has been proposed that a hole is provided in the end surface of the bar and a tool is attached to this hole to easily align the axes of the tool and the bar. However, since the joining of the drill etc. and the bar is due to brazing, there is a problem due to the brazing as described above, that is, the strength and warpage of the bar etc. around the joint occur. The problem of is left unsolved.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a drilling tool suitable for highly accurate drilling work and easy to manufacture.

[0010]

In order to achieve the above object, the invention according to claim 1 is a hole making jig comprising a rod and a blade such as a drill or a tap attached to the tip of the rod. A tool mounting hole is provided in the tip end surface of the bar, and the tool is inserted into the tool mounting hole, and the outer peripheral surface of the bar is irradiated with a pulsed YAG laser beam, thereby welding the bar and the tool. It is characterized by

According to a second aspect of the present invention, the laser beam is a pulsed YAG laser beam.

The invention according to claim 3 is characterized in that welding by irradiation of a laser beam is performed at a plurality of positions.

[0013]

According to the present invention, the heat during welding reaches only a part of an extremely narrow range, the decrease in strength of the bar and the blade due to the heat and the occurrence of warpage are prevented, and the bar and the blade are separated from each other. The axis alignment can also be done by a simple operation of inserting the blade into the blade mounting hole.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of a drilling tool according to the present invention will be described in detail below with reference to FIGS.

As shown in FIG. 1, this drilling tool comprises a bar 1 having a circular cross section and a blade 2 such as a drill or a tap attached to the tip of the bar 1.

A blade mounting hole 3 having a constant depth is formed in the tip end surface of the rod 1, and the blade 2 is inserted and mounted in the blade mounting hole 3.

The axis of the blade mounting hole 3 is formed to be the same as the axis of the bar 1, so that the axis of the blade 2 inserted into the blade mounting hole 3 is aligned with the axis of the bar 1. It is provided in.

The rod 1 and the blade 2 are joined by laser beam welding, and a pulsed YAG (yttrium, aluminum, garnet) laser beam L is used as the laser beam.

That is, when joining the bar 1 and the blade 2, the blade 2 is inserted into the blade mounting hole 3 in advance, and then,
The outer peripheral surface of the rod 1 is irradiated with a pulsed YAG laser beam L. At this time, the area of the irradiation point is the blade mounting hole 3
Around the

When such a region is irradiated with the pulsed YAG laser beam L from the outer peripheral surface side of the bar 1, the outer peripheral surface of the bar 1 is directed toward the center of the blade 2 as shown in FIG. A wedge-shaped melting zone a is formed in a narrow range, and thereby the rod 1 and the blade 2 are welded.

At this time, when the YAG laser beam L is gradually moved along the bar 1, a wedge-shaped melting zone a is continuously formed along the bar 1, and the bar 1 is formed by linear welding. And the blade 2 can be integrated.

In the welding with the pulsed YAG laser beam L, the welding can be performed by narrowing down the welding to a very narrow range, and while the beam is intermittently interrupted, the base material to be irradiated, that is, the bar 1 and Since the blade 2 cools, the strength and warpage of the bar 1 and the blade 2 due to heat such as brazing will not occur.

The wedge-shaped melting zone a is formed not to reach the center of the cutting tool 2 as shown in FIG. 2, but to the middle thereof as shown in FIG. 3, or to near the center of the cutting tool 2 as shown in FIG. 3, or as shown in FIG. Thus, it may be formed until it penetrates the blade 2.

The position at which the wedge-shaped melting zone a is formed can be appropriately selected by adjusting the output of the YAG laser beam.

The welding with the YAG laser beam L may be conducted at one place, but may be conducted at a plurality of places from the viewpoint of bonding strength and the like.

Therefore, the drilling tool of the above embodiment is
The blade 2 is inserted into the blade mounting hole 3 provided on the tip end surface of the bar 1 and is welded with a pulsed YAG laser beam L to integrally bond the bar 1 and the blade 2. For this reason, the heat at the time of welding reaches only a part of an extremely narrow range, the strength of the bar 1 and the blade 2 due to the heat, the occurrence of warpage, etc. are prevented, which is suitable for highly accurate drilling work. Further, the axial alignment between the rod 1 and the blade 2 can be performed by a simple operation of inserting the blade 2 into the blade mounting hole 3, and the manufacturing is easy.

A pipe may be used as the rod 1, and when the pipe is used, the inside of the pipe can be directly used as the blade mounting hole 3.

Further, in the above embodiment, pulse oscillation YAG is used.
Although the laser beam is used, any other laser beam may be used as long as it is a laser beam equivalent to the pulsed YAG laser beam.

[0029]

According to the drilling tool of the present invention,
As described above, the tool is inserted into the tool mounting hole provided on the tip surface of the bar, and the tool is welded with a laser beam to integrally join the bar and the tool. For this reason, the heat during welding reaches only a part of an extremely narrow range, which prevents the strength and warpage of the bar and blade from occurring due to the heat, and the axis of the bar and the blade is aligned with the blade. Since it can be performed by a simple operation of inserting it into the mounting hole, there is an effect that it is possible to provide a drilling tool that is suitable for highly accurate drilling work and that is easy to manufacture.

Even in the inventions according to claims 2 and 3, the same effects as described above can be obtained.

[Brief description of drawings]

FIG. 1 is a perspective view of an embodiment of a drilling tool according to the present invention.

FIG. 2 is a sectional view taken along line II-II shown in FIG.

FIG. 3 is a sectional view taken along line II-II shown in FIG.

FIG. 4 is a sectional view taken along line II-II shown in FIG.

FIG. 5 is a front view of a conventional drilling tool.

[Explanation of symbols]

 1 bar 2 blade 3 blade mounting hole LYAG laser beam

Claims (3)

(57) [Claims] 1. A drilling tool comprising a rod and a blade such as a drill or a tap attached to the tip of the rod, wherein a tool mounting hole is provided on the tip surface of the bar, and the tool is mounted in the tool mounting hole. A hole making tool, characterized in that the rod is irradiated with a laser beam while the rod is being inserted, and the rod and the blade are thereby welded. 2. The drilling tool according to claim 1, wherein the laser beam is a pulsed YAG laser beam. 3. The drilling tool according to claim 1 or 2, wherein welding by laser beam irradiation is performed at a plurality of locations.