JP2003127016A - Drilling tool - Google Patents

Abstract

(57) [Problem] To provide a drilling tool capable of grasping in real time the depth of drilling during drilling work. SOLUTION: The present invention relates to a drilling tool in which a cutting tip 6 is fixed to a distal end portion 2 of a cylindrical bit shank 1, and on the outer peripheral surface of the bit shank 1, an object to be drilled by the bit shank 1 is provided. And a scale means 5 for grasping the depth of the perforation.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drilling tool such as a core bit or a hole saw, in which a cutting tip is fixed to the tip of a cylindrical bit shank.

[0002]

2. Description of the Related Art Conventionally, core bits have been used for perforating reinforced / steel-framed concrete, asphalt, bricks, stones, etc., sampling, perforating guardrail fences, etc. This type of core bit includes a cylindrical bit shank, and a plurality of cutting chips made of a metal sintered product containing, for example, diamond abrasive grains and fixed to the tip of the bit shank by brazing at regular intervals. In general, a rotating force of a drill is applied by fitting an adapter mounted on a chuck of a rotary drive machine (hereinafter referred to as a drill) such as an electric motor to the base end portion of the bit shank.

[0003]

By the way, in the conventional core bit described above, at the final stage of the drilling operation, that is, near the time when the hole is removed, excessive pressing force is applied to the object to be drilled, so that the fluff (on the exit side) There is a risk that the edge of the hole will be chipped), and when the hole is removed, the reaction force of the pressing force received from the object to be drilled is suddenly lost, and the worker may lose balance and be injured.
Therefore, it is extremely important to know the depth of drilling during the drilling work in terms of work quality and safety.

As a solution to this problem, a drill having a stopper function for generating a signal for stopping the driving of the electric motor by contacting the surface of the object to be drilled is used, depending on the thickness of the object to be drilled which is grasped in advance. Although it is conceivable to adjust the position of the stopper in advance before the punching work, this method hinders the speed of the punching work and complicates the work of the positioning adjustment.

On the other hand, when a drill having no stopper function is used, the core bit is temporarily removed during the drilling work, a ruler is inserted into the hole, and the drilling depth at that time is measured several times. It is necessary to repeat the process for a long time, and even in this method, the speed of the drilling work is impeded, and a series of works for measuring the drilling depth is complicated.

The above-mentioned problem is not limited to the core bit, but is a problem that other drilling tools such as a hole saw to which a cemented carbide cutting tip is fixed have.

Therefore, the present invention has been made in view of the above problems, and an object thereof is to provide a drilling tool capable of grasping the drilling depth during a drilling operation in real time.

[0008]

In order to solve the above problems, a drilling tool according to the present invention is provided with a cylindrical bit shank 1.
In the drilling tool in which the cutting tip 6 is fixed to the tip portion 2 of the, the scale means 5 for grasping the drilling depth to the drilling object is formed on the outer peripheral surface of the bit shank 1. Configured.

According to the drilling tool having the above structure, the scale means 5 sequentially enters the object to be drilled as the drilling progresses. That is, the depth of perforation can be grasped in real time by visually grasping the entering amount of the scale means 5.

Further, the drilling tool according to the present invention is defined by claim 2.
As noted, the scale means 5 includes a bit shank 1
It is possible to employ a configuration in which the scales are engraved at regular intervals along the axial direction of the. In this case, if the scale includes at least a line segment in the circumferential direction of the bit shank 1, it is possible to grasp the tilt (vertical degree) of the bit shank 1 with respect to the surface of the object to be drilled and perform appropriate drilling. .

Furthermore, in the drilling tool according to the present invention, as described in claim 3, the scale means 5 is a circumferential annular line formed at regular intervals along the axial direction of the bit shank 1. A configuration can be adopted. According to such a configuration, the visibility of the scale means 5 during the rotation of the bit shank 1 is enhanced, so that the drilling depth and the tilt of the bit shank 1 can be more accurately grasped. still,
The annular line is a concept including not only a solid line but also a partially broken line such as a broken line, a dotted line, and a dash-dotted line, which is visually recognized in a similar manner to the solid line due to an afterimage phenomenon.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION The structure of a core bit, which is an embodiment of a drilling tool according to the present invention, will be described in detail below with reference to the drawings.

The core bit according to this embodiment has a plurality of cutting tips 6, ...
A configuration in which the components are fixed at regular intervals, more specifically,
A plurality of substantially rectangular notches 2a, ... Are provided in the tip portion 2 of the cylindrical bit shank 1 at regular intervals along the circumferential direction,
A part of a substantially rectangular parallelepiped cutting tip 6 made of a sintered metal containing diamond abrasive grains is inserted into each notch 2a and fixed by brazing or the like.

A spiral groove 4 is formed on the outer peripheral surface of the bit shank 1.
Is engraved. A plurality of spiral grooves 4 are formed around the axis of the bit shank 1, and a plurality of spiral bands 4a formed by the plurality of spiral grooves 4 ,.
... perform a spiral movement upward with the rotation of the bit shank 1 around the axis.

As a result, the cutting dust generated by the conventional core bit during drilling remains, and the cutting dust enters between the side surface of the bit shank 1 and the cutting side surface or between the cutting tip 6 and the cutting surface to cause the drilling. As the amount of cutting dust between the side surface of the bit shank 1 and the cutting side surface increases, the load resistance to the rotation of the bit shank 1 increases, the cutting speed is extremely reduced, and the bit shank 1 And the object to be perforated are in mesh with each other and cannot be rotated, or when the amount of cutting dust around the cutting tip 6 increases, the cutting tip 6 does not hit the cutting surface, resulting in extremely high cutting speed. The problems are solved, such as lowering and finally making it impossible to drill.

Scales 5 are engraved along the axial direction of the bit shank 1 on the outer peripheral surface of the bit shank 1 in which the spiral grooves 4, ... Are formed. In the present embodiment, the scale 5 is provided by laser marking (may be an etching process or the like), and includes one line segment along the axial direction and the tip 2 of the bit shank 1. With the end face of 0 as 0, and the line segment along the circumferential direction that is orthogonal to the long line segment and is cut by 10 mm in the axial direction.

When forming the scale 5, the bit shank 1
The cutting tip 6 is worn and causes a dimensional change with use because the end surface of the tip portion 2 of the bit shank 1 is used as a reference, but the end surface of the tip portion 2 of the bit shank 1 is always in non-contact with the cutting surface. That is, there is no dimensional change. However, the scale 5 is based on the base end side edge of the cutting tip 6 (base end side edge of the notch 2a), that is, the position that is one end of the effective length of the core bit, or the tip side end of the cutting tip 6 You may form based on an edge.

Further, at the base end portion 3 of the bit shank 1,
Locking notch 3 with its edge cut out in a substantially L-shape in side view
At least two circular holes a and circular through holes 3b are formed at regular intervals in the circumferential direction. This locking notch 3a
The through hole 3b is for integrating the core bit when the core bit is mounted on the adapter 7, and the notch 3a for locking.
The first projection 9a of the adapter 7 engages with the, and the second projection 9b of the adapter 7 engages with the through hole 3b.

The first protrusions 9a are columnar protrusions, and the second protrusions 9b are ball-shaped protrusions which are retracted by pressing, and both are provided so as to protrude on the outer peripheral surface of the insertion portion 9 inserted into the bit shank 1. There is. The first protrusion 9a is the notch 3a for locking.
When the adapter 7 is inserted into the base end portion 3 of the bit shank 1 at a position where it can be engaged with the bit shank 1, and then the adapter 7 is rotated in the circumferential direction with respect to the bit shank 1, the first protrusion 9a is formed.
Comes into contact with the end of the locking notch 3a, and a part of the second protrusion 9b is inserted into the through hole 3b, so that the bit shank 1 and the adapter 7 are integrated.

The adapter 7 is provided with a prism-shaped gripping portion 8 coaxially with the bit shank 1, and by mounting this gripping portion 8 on a chuck of a drill (not shown), rotation of the drill becomes a core bit. It is provided so that the core bit can rotate around the axis.

The core bit according to the present embodiment has the above-mentioned configuration, and the scale 5 which is a characteristic part of the present embodiment.
Is used as follows with reference to FIG.

An object to be drilled, for example, a concrete wall H
When performing the drilling work, the thickness of the concrete wall H and the protruding amount of the cutting tip 6 from the end surface of the tip portion 2 of the bit shank 1 are first grasped. In the present embodiment, if the former is 100 mm and the latter is 5 mm, the position of the scale 5 indicated by the concrete wall surface when the cutting tip 6 penetrates the concrete wall H is 95 mm.

If the timing at which the core bit penetrates the concrete wall H is known, it is advisable to reduce the rotation speed of the drill before that or to reduce the pressing force against the concrete wall.
Specifically, if the rotation speed of the drill is reduced immediately before the insertion amount of the bit shank 1 is 95 mm, or if the pressing force of the drill is weakened, it is highly possible that the back surface of the concrete wall will be covered with a gravel just before the hole comes out. Also, the reaction force received from the concrete wall H suddenly disappears at the time of pulling out, and there is no concern that the worker may lose balance and be injured.

Further, according to the core bit having the above-mentioned structure, since the drilling depth can be grasped in real time even during the drilling work, the work of extracting the core bit and measuring the hole depth during the drilling work is unnecessary. Moreover, since it is not necessary to use a drill having a stopper function, the drilling work can be performed quickly and easily.

Further, according to the core bit having the above structure,
Since the scale means has line segments engraved in the circumferential direction, it is possible to grasp the inclination of the core bit with respect to the surface of the concrete wall. That is, if it is found that the line segment is inclined with respect to the concrete wall surface during the drilling work, correct this (make the concrete wall surface and the line segment parallel).
By correcting the inclination of the core bit in this way, it is possible to make a hole at a right angle to the wall surface.

The drilling tool according to the present invention is not limited to the above embodiment, and various modifications can be made without departing from the gist of the present invention.

The scale means is not limited to the above-mentioned embodiment, and for example, circumferential annular lines (solid line, broken line, dotted line, etc.) formed at regular intervals along the axial direction of the bit shank 1. (Including the one-dot chain line), the visibility of the scale means is high even when the rotation speed of the bit shank 1 is high, and the parallelism between the annular line and the surface of the object to be drilled can be grasped. Since it is easy, it is effective for knowing the drilling depth of the drilling tool and the perpendicularity to the surface of the drilling object.

Alternatively, a colored band pattern in the circumferential direction may be applied at regular intervals in the axial direction of the bit shank 1, or in the circumferential direction having a constant width in the axial direction of the bit shank 1. The band pattern may be sequentially changed in color in the axial direction of the bit shank 1, or the color pattern or marks may be stamped at appropriate positions in the axial direction of the bit shank 1.

Further, the scale means is not limited to the one engraved on the outer peripheral surface of the bit shank 1, and may be a means for printing or affixing a seal. Here, as the scale means by printing or the scale means composed of a seal, one having a strong adhesiveness with the bit shank 1 is used so as not to be peeled off by sliding contact with the object to be punched in the punching work, or It is preferable to take measures to coat the surface with a protective film. However, in the bit shank 1 in which the spiral groove 4 is provided, since it is almost unnecessary to consider the influence of the sliding contact between the spiral groove 4 and the object to be drilled, printing is performed only on the spiral groove 4. Or
The scale may be configured by attaching a seal.

Even when the scale means as in the above embodiment is provided, at least two or more pairs may be provided by shifting the positions in the circumferential direction of the outer peripheral surface of the bit shank 1. For example, if the scale means is provided in the circumferential trisecting position on the outer peripheral surface of the bit shank 1, when the rotation of the drilling tool is once stopped and the drilling depth is confirmed by the scale means, either scale is used. The means will always be in the operator's field of view, and as a result,
This is useful because it eliminates the complexity of searching for a scale means on the bit shank 1.

Further, in the above embodiment, a plurality of cutting tips 6, ... Are provided and fixed to the tip portion 2 of the bit shank 1 at regular intervals along the circumferential direction. However, the present invention is not limited to this, and for example, even when a ring-shaped cutting tip is adopted or a plurality of cutting tips are adopted, they can be arranged at irregular intervals.

[0032]

Since the drilling tool according to the present invention is provided with the scale means on the outer peripheral surface of the bit shank for grasping the drilling depth to the drilling object, the drilling depth during drilling work is grasped in real time. In addition, there is no need to use a drill with a stopper function, or to temporarily interrupt the drilling work to remove the drill and measure the drilling depth, resulting in quick and easy drilling work. You will be able to do it.

[Brief description of drawings]

FIG. 1 shows a side view of a core bit according to one embodiment of the present invention.

FIG. 2 is a side view showing a state in which the core bit of the same embodiment is being perforated in a concrete wall.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Bit shank, 2 ... Tip, 2a ... Notch, 3 ... Base end, 3a ... Locking notch, 3b ... Through hole, 4 ... Spiral groove, 4
a ... spiral band, 5 ... scale (scale means), 6 ... cutting tip, 7 ... adapter, 8 ... gripping part, 9 ... insertion part, 9a
… The first protrusion

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 3C037 AA05 DD05 FF02                 3C069 AA04 BA09 BB01 CA07 CA12                       EA05

Claims (3)

[Claims] 1. A drilling tool comprising a cutting tip (6) fixed to a tip portion (2) of a cylindrical bit shank (1), wherein an object to be drilled is provided on the outer peripheral surface of the bit shank (1). A drilling tool, characterized in that scale means (5) for grasping the drilling depth into the hole is formed. 2. The drilling tool according to claim 1, wherein the scale means (5) is a scale provided at regular intervals along the axial direction of the bit shank (1). 3. The drilling tool according to claim 1, wherein the scale means (5) is a circumferential annular wire line provided at regular intervals along the axial direction of the bit shank (1).