WO2018052118A1

WO2018052118A1 - Core drill

Info

Publication number: WO2018052118A1
Application number: PCT/JP2017/033472
Authority: WO
Inventors: 宮永　昌明
Original assignee: 株式会社ミヤナガ
Priority date: 2016-09-16
Filing date: 2017-09-15
Publication date: 2018-03-22
Also published as: JP2018043327A

Abstract

Provided is a core drill capable of reducing powder dust that scatters outward during drilling work, even on a drilling spot having, at a location immediately near thereto, a wall or the like vertical to the surface to be drilled. An exemplary core drill according to the present invention is provided with: a shaft part (1) including a shank; a blade body part (2) including a cylindrical section (21) fixed to the front portion of the shaft part (1) and including a cutting blade (22) disposed at the leading edge of the cylindrical section; and a dust suction adapter (4) including a fitting part (4a) that is penetrated by the shaft part (1) and that is rotatably attached relatively to the shaft part (1), and including a suction port (4b) which is joined to the fitting part and which is connected to a suction hose, wherein a dust suction passage (15) is provided inside the shaft part (1), a discharge port (16) which is connected with the dust suction passage (15) is provided on a side surface of the shaft part (1), and the dust suction adapter (4) is configured in such a way that the suction port (4b) and the discharge port (16) of the shaft part (1) are always connected in a state where the shaft part (1) is relatively rotating with respect to the fitting part (4a).

Description

Core drill

The present invention relates to a core drill used for drilling an object to be drilled made of metal, stone, concrete, wood, composite material or the like.

粉 When drilling a drilling object made of metal, stone, concrete, wood, composite material, etc. using a drill, dust, mainly chips, is generated. For this reason, the dust collection tool for drilling tools (for example, refer patent documents 1 and 2) which prevented dusts, such as a chip, from scattering around is proposed.

This dust collecting device has a box-like shape, has a box opened downward, an opening for inserting a drill is formed on the upper surface of the box, and a base end is a suction device ( A suction port connected to the tip of a suction hose connected to a dust collector is formed in the box.

JP 2006-192525 A JP 2008-68328 A

For example, when performing a drilling operation using a core drill provided at the tip of a cylindrical tube with a cutting edge and the box-shaped dust collector, a box-shaped dust collector may be used in addition to the core drill. Since it is used, the number of parts increases. Further, since the box-shaped dust collector surrounds the periphery of the cylindrical portion of the core drill, the exclusive area of the dust collector is wider than the size of the hole to be opened. Therefore, when there is a wall or a protrusion perpendicular to the drilling target surface in the immediate vicinity of the drilling location and there is no space for installing the dust collector box, the dust collector cannot be used.

The present invention has been made to solve the above-described problems, and without using a box-shaped dust collector, there is a wall, a protrusion, or the like perpendicular to the drilling target surface in the immediate vicinity of the drilling site. An object of the present invention is to provide a core drill capable of reducing dust scattered outside even during drilling.

In order to achieve the above object, a core drill according to an aspect of the present invention includes a shaft portion having a shank at a rear portion, a cylindrical tube portion whose base end is fixed to a front portion of the shaft portion, and the tube portion. A blade body portion having a cutting edge disposed at the tip of the blade, a mounting portion that is penetrated by the shaft portion and attached to be relatively rotatable with respect to the shaft portion, and a dust absorber coupled to the mounting portion. A dust suction adapter having a suction port connected to the tip of the suction hose, and the shaft portion is provided with a dust suction passage extending rearward from the front end thereof, and the dust suction adapter is disposed on a side surface of the shaft portion. A discharge port communicating with a rear end portion of the passage is provided, and the dust suction adapter is configured so that the suction port and the discharge port of the shaft portion are in a state where the shaft portion rotates relative to the mounting portion. Are always in communication.

According to this configuration, dust generated during the drilling operation passes through the internal space of the cylindrical portion of the blade body portion, the dust suction passage and discharge port of the shaft portion, and the inside of the dust suction adapter, and is sucked into the dust suction machine. The And since there is no box-shaped dust collector with a large area that surrounds the cylindrical part of the conventional core drill, there are walls and protrusions perpendicular to the drilling target surface in the immediate vicinity of the drilling site. Even in such a perforated place, dust generated during the perforating work can be collected to the dust absorber via the dust suction adapter, and dust scattered outside can be reduced.

A positioning shaft shape whose base end is attached to the front end of the shaft portion, extends forward through the center of the cylindrical portion of the blade body portion, and has a distal end protruding forward of the cutting edge of the blade body portion. A member may further be provided, and the shaft-like member may be provided with a communication path that connects the outer surface of the shaft-shaped member and the dust suction path.

In this case, the dust generated during the drilling operation passes through the internal space of the cylindrical portion of the blade body portion, the communication passage of the shaft-like member, the dust suction passage and discharge port of the shaft portion, and the inside of the dust suction adapter. Sucked into the machine.

The shaft-shaped member may be a center pin that is detachably attached to the front end of the shaft portion and can expand and contract in the axial direction.

The shaft-shaped member may be a center drill that opens a center hole in a drilling target.

The present invention has a configuration as described above, and without using a box-shaped dust collecting device, there is a perforated portion where a wall or a protrusion perpendicular to the perforation target surface is present in the immediate vicinity of the perforated portion. Even so, there is an effect that it is possible to provide a core drill capable of reducing dust scattered to the outside during the drilling operation.

FIG. 1 is a side view showing a part of a core drill of a configuration example of an embodiment of the present invention in cross section. FIG. 2 is an exploded view of the core drill of FIG. FIG. 3 is a side view showing an example of a center drill.

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. In the following description, the same or corresponding elements are denoted by the same reference symbols throughout all the drawings, and redundant description thereof is omitted. Further, the present invention is not limited to the following embodiment.

(Embodiment)
FIG. 1 is a side view showing a part of a core drill (core drill bit) of a configuration example of an embodiment of the present invention in cross section. FIG. 2 is an exploded view of the core drill of FIG. In the following, for the sake of convenience, as shown in FIG. 1, “front” and “rear” of the core drill are determined and described.

This core drill is a drilling device including a shaft portion 1 having a shank 11 at the rear portion, a blade body portion 2, a center pin 3 which is an example of a positioning shaft-like member, and a dust suction adapter 4.

The shaft portion 1 has a shank 11 detachably attached to a chuck of a rotary tool (for example, an electric drill or a pneumatic drill) at the rear portion, and a male screw portion for attaching the blade body portion 2 to the outer wall of the front portion. 12 is provided. An insertion hole 14 for attaching the positioning center pin 3 is provided at the tip of the shaft portion 1.

The shaft portion 1 has an adapter mounting portion 13 between the shank 11 and the male screw portion 12, and the adapter mounting portion 13 is formed with an annular groove 17 (FIG. 2) in which the O-ring 5 is fitted. Yes. A dust suction passage (elongated space) 15 is formed in the front portion of the shaft portion 1 (the male screw portion 12 or the adapter mounting portion 13). Is provided. A discharge port 16 communicating with the rear end portion of the dust suction passage 15 is provided on the side surface of the adapter mounting portion 13 of the shaft portion 1. The discharge port 16 communicates the rear end portion of the dust suction passage 15 and the surface of the side surface of the adapter mounting portion 13 and is formed by, for example, a round hole.

The blade body portion 2 includes a cylindrical tube portion 21, a plurality of cutting blades 22 fixed to the tip of the tube portion 21, and an attachment portion 23 attached to the front portion of the shaft portion 1 on the proximal end side of the tube portion 21. And have. A plurality of cutting edges 22 are arranged at appropriate intervals in the circumferential direction at the tip of the cylindrical portion 21, and may be composed of, for example, a segment grindstone containing diamond particles, or composed of a cemented carbide chip or the like. May be. Further, the cutting edge 22 is not a plurality, but may be an annular one in which a cutting edge made of a sintered alloy containing diamond abrasive grains is provided on the entire periphery of the tip of the cylindrical portion 21.

The mounting portion 23 has a cylindrical shape, and an internal thread portion 23a that is screwed with the external thread portion 12 of the shaft portion 1 is provided on the inner wall thereof. Therefore, the blade body portion 2 is fixed to the front portion of the shaft portion 1 by screwing the female screw portion 23 a with the male screw portion 12. In addition, in this example, the case where the diameter of the attachment part 23 is smaller than the diameter of the cylinder part 21 is illustrated, but when the diameter of the attachment part 23 is equal to the diameter of the cylinder part 21 or from the diameter of the cylinder part 21. Can also be large.

The center pin 3 is a shaft-like member provided for positioning, can be expanded and contracted in the axial direction (front-rear direction), and when in the most extended state, the tip is forward of the cutting edge 22 as shown in FIG. Protruding to Specifically, as shown in FIG. 2, the center pin 3 includes a first body portion 31 on the proximal end side, a second body portion 32 on the distal end side, and a compression spring 33. In addition, a disk-like pin support portion 34 is fixed to the center pin 3 at a portion near the tip of the second main body portion 32. The outer peripheral side surface of the pin support portion 34 is in contact with the inner surface of the cylindrical portion 21 so as to be slidable in the front-rear direction.

An insertion portion 35 to be inserted into the insertion hole 14 at the distal end of the shaft portion 1 is provided at the proximal end portion of the first main body portion 31. The first main body 31 and the second main body 32 are connected to each other so as to be slidable in the axial direction (front-rear direction) within a predetermined range. And the compression spring 33 is accommodated in the inside of the 1st main-body part 31 and the 2nd main-body part 32, and the 1st main-body part 31 and the 2nd main-body part 32 are axial direction (front-back direction) by the compression spring 33, and It is urged away from each other. Thereby, the center pin 3 can be expanded and contracted in the axial direction.

When the insertion portion 35 of the center pin 3 is inserted into the insertion hole 14 of the shaft portion 1 and the center pin 3 is attached and is not pressed against the object to be drilled, the tip of the center pin 3 is shown in FIG. Thus, it is in the state which protruded ahead rather than the front-end | tip of the blade part 2, and when it is pressed on a drilling target object, the full length will shrink. The center pin 3 is detachably attached to the insertion hole 14 of the shaft portion 1. The above configuration is known.

In the center pin 3 of the present embodiment, the disk-shaped pin support portion 34 is provided with one or a plurality of holes 34a that serve as air (dust) suction ports. For example, the number of holes 34a is preferably increased as the diameter of the cylinder portion 21 increases. In addition, when the pin support part 34 is not disc-shaped but has a shape that allows air to easily flow in the front-rear direction across the pin support part 34, the hole 34a may not be provided.

And the hole 36a connected to the dust suction passage 15 of the shaft portion 1 and extending in the front-rear direction is provided in the insertion portion 35 on the proximal end side of the first main body portion 31 and in the vicinity thereof. Further, a through hole 36b orthogonal to the hole 36a is provided. These holes 36 a and through-holes 36 b form a communication path 36 that connects the outer surface of the center pin 3 and the dust suction path 15. Thereby, the internal space P3 of the blade body part 2 and the discharge port 16 of the shaft part 1 are connected by the communication path 36 and the dust suction path 15.

The dust suction adapter 4 is formed of resin or the like, and has a configuration in which an annular mounting portion 4a and a cylindrical suction port 4b are coupled. When using this core drill, the tip of the suction hose of an external dust suction device (suction device) is connected to the suction port 4b. The proximal end of the suction hose is connected to a dust absorber.

The mounting portion 4a is configured so that the shaft portion 1 is penetrated and attached to the shaft portion 1 so as to be relatively rotatable. Specifically, the mounting portion 4a is provided with an insertion hole 41 through which the adapter mounting portion 13 of the shaft portion 1 is inserted in the front-rear direction. A wide annular groove 42 having a larger diameter than the insertion hole 41 is provided on the side wall at the center of the insertion hole 41, and the annular groove 42 is connected to the internal space P2 of the cylindrical suction port 4b. An annular groove 43 into which the O-ring 5 is fitted is provided on the side wall of the insertion hole 41.

With the O-ring 5 fitted in the annular groove 17 (FIG. 2) of the shaft portion 1, the shaft portion 1 is passed through the insertion hole 41 of the dust suction adapter 4 from the shank 11 side, and the O-ring 5 is fitted in the annular groove 43. Thus, the dust suction adapter 4 is mounted on the adapter mounting portion 13 of the shaft portion 1. At this time, the dust suction adapter 4 is attached so as to be rotatable relative to the shaft portion 1, and the shaft portion 1 rotates in a state where the suction hose of the dust suction device (suction device) is connected to the suction port 4 b. Even if the dust suction adapter 4 does not rotate.

Further, an annular space P1 is formed by an annular groove 42 between the surface of the adapter mounting portion 13 of the shaft portion 1 and the mounting portion 4a of the dust suction adapter 4, and this annular space P1 and the internal space P2 of the suction port 4b Is continuous. Therefore, even if the shaft portion 1 rotates without the dust suction adapter 4 rotating, the discharge port 16 of the shaft portion 1 and the internal space P2 of the suction port 4b are always connected via the annular space P1.

That is, the leading end portion of the blade body 2 and the spaces P1 and P2 inside the dust suction adapter 4 are the holes 34a of the disk-shaped pin support portion 34, the internal space P3 of the blade body 2 and the communication path of the center pin 3. 36, the shaft 1 is configured to always communicate with each other via the dust suction passage 15 and the discharge port 16.

When drilling using the core drill in this embodiment, the shank 11 is attached to the chuck of the rotary tool, and the suction hose of the dust suction machine is connected to the suction port 4b of the dust suction adapter 4 to operate the rotary tool and the dust suction machine. To do. By operating the rotary tool, the center pin 3 and the pin support portion 34 rotate together with the shaft portion 1 and the blade body portion 2 with the central axis extending in the front-rear direction of the shaft portion 1 as the rotation axis. Does not rotate.

時には Use with the center pin 3 attached at the start of drilling. First, the tip of the center pin 3 is drilled in accordance with the center of the hole drilled by the blade body part 2 (cutting edge 22), and is cut, for example, about 2 to 3 mm until the tip of the blade body part 2 enters the drilling object. . After positioning is completed in this manner, the center pin 3 is used with the center pin 3 removed and drilled to a desired depth. The center pin 3 can be easily removed by pulling it forward.

When drilling with the center pin 3 attached at the start of the drilling operation, dust such as chips generated by cutting by the cutting blade 22 at that time is indicated by an arrow in FIG. Through the hole 34a, the internal space P3 of the blade body part 2, the communication path 36 of the center pin 3, the dust suction path 15 and the discharge port 16 of the shaft part 1, and the spaces P1 and P2 inside the dust suction adapter 4. Sucked into. At this time, dust to be scattered outside the tube portion 21 can also be sucked into the tube portion 21 from the hole 34 a of the pin support portion 34.

Next, when the center pin 3 is removed, the pin support portion 34 fixed thereto is also removed. In the case of drilling in this state, dust such as swarf is generated in the internal space P3 of the blade part 2, the insertion hole 14 of the shaft part 1, the dust suction passage 15 and the discharge port 16 of the shaft part 1, and the inside of the dust suction adapter 4. Passes through the spaces P1 and P2, and is sucked into the dust collector. In this case, the insertion hole 14 of the shaft portion 1 is a part of the dust suction passage.

As described above, the dust generated during the drilling operation can be recovered to the external dust collector via the dust suction adapter 4.

And in this embodiment, since the box-shaped dust collector with a large exclusive area surrounding the circumference of the cylindrical part of the conventional core drill is not used, a wall or protrusion perpendicular to the drilling target surface is located immediately near the drilling site. Even in a perforated part where there is a portion or the like, dust generated during the perforating work can be collected to the dust absorber via the dust suction adapter 4, and dust scattered outside can be reduced.

In the present embodiment, the center pin 3 is used as the positioning shaft-shaped member. However, instead of the center pin 3, a center drill (a drill bit for making a center hole) may be used. An example of the configuration of the center drill in this case is shown in FIG.

The center drill 6 shown in FIG. 3 has a cutting edge 60a formed at the tip of a shaft body 60, and a fixed portion 60b fixed with a set screw, for example, at the base end. In this case, the shaft portion 1 of the core drill is provided with an insertion portion into which the base end portion of the center drill 6 can be inserted in the front portion of the shaft portion 1 in order to fix the center drill 6. Furthermore, a screw hole that is screwed with the set screw for fixing the fixed portion 60b in a state where the base end portion of the center drill 6 is inserted into the insertion portion is provided.

The shaft body 60 of the center drill 6 is provided with a hole 61a extending in the axial direction (front-rear direction) from the base end and a through hole 61b orthogonal to the hole 61a. The hole 61 a is provided so as to be connected to the dust suction passage 15 of the shaft portion 1, and the communication passage 61 that communicates the outer surface of the center drill 6 and the dust suction passage 15 of the shaft portion 1 by the hole 61 a and the through hole 61 b. Is formed. The communication path 61 corresponds to the communication path 36 of the center pin 3 described above, and the internal space P3 of the blade part 2 and the discharge port 16 of the shaft part 1 are connected by the communication path 61 and the dust suction path 15. Connected.

When such a center drill 6 is used, the center drill 6 is always fixed to the shaft portion 1 during drilling, and the tip portion of the center drill 6 protrudes beyond the tip of the blade body portion 2. It has become.

In this case, the drilling operation is started by aligning the tip of the center drill 6 with the center of the hole drilled by the blade body 2. Then, first, a center hole is drilled in the drilling object with the center drill 6, and when the blade body 2 reaches the drilling object, a hole with a desired diameter is drilled in the blade body 2. That is, the center drill 6 has a positioning function that becomes a rotation center with respect to the cutting by the cutting edge 22 of the blade body portion 2.

In this case, dust such as swarf generated by cutting with the cutting edge 22 during drilling work is generated in the internal space P3 of the blade body part 2, the communication path 61 of the center drill 6, the dust suction path 15 and the discharge port 16 of the shaft part 1. Then, it passes through the spaces P1, P2 inside the dust suction adapter 4 and is sucked into the dust suction machine.

The communication path of the center drill 6 is not limited to the communication path 61 as long as it is configured to communicate the outer surface of the center drill 6 and the dust suction path 15 of the shaft portion 1. For example, without providing the through hole 61b, a through hole 62 in which the hole 61a extending in the axial direction is further extended as indicated by a two-dot chain line may be provided as the communication path.

Further, a configuration in which neither the center pin 3 nor the center drill 6 is provided may be employed. In this case, the dust suction passage 15 of the shaft portion 1 is formed up to the front end of the shaft portion 1 so as to be connected to the internal space P3 of the blade body portion 2. In this case, an auxiliary tool or the like for positioning may be separately provided outside the blade body part 2.

From the above description, many modifications and other embodiments of the present invention are apparent to persons skilled in the art. Accordingly, the foregoing description should be construed as illustrative only and is provided for the purpose of teaching those skilled in the art the best mode of carrying out the invention. The details of the structure and / or function may be substantially changed without departing from the spirit of the invention.

The present invention does not use a box-shaped dust collecting device, and even during a drilling operation, even in a drilling site where there is a wall or a protrusion perpendicular to the drilling target surface in the immediate vicinity of the drilling site, It is useful as a core drill that can reduce dust scattered outside.

DESCRIPTION OF SYMBOLS 1 Shaft part 2 Blade part 3 Center pin 4 Dust absorption adapter

4a Mounting part

4b Suction port 6 Center drill 11 Shank 15 Dust collection path 16 Discharge port 21 Cylinder part 22 Cutting edge 36 Communication path 61 Communication path

Claims

A shank having a shank at the rear,
A blade body portion having a cylindrical tube portion whose base end is fixed to the front portion of the shaft portion, and a cutting blade disposed at the tip of the tube portion;
A dust-absorbing adapter having a mounting portion that is penetrated by the shaft portion and is rotatably attached to the shaft portion, and a suction port that is coupled to the mounting portion and connected to a tip of a suction hose of a dust suction device When,
With
The shaft portion is
A dust suction passage extending backward from the front end of the dust suction passage is provided inside, and a discharge port communicating with a rear end portion of the dust suction passage is provided on a side surface of the shaft portion.
The dust suction adapter is
In the state where the shaft portion is rotating relative to the mounting portion, the suction port and the discharge port of the shaft portion are configured to always communicate with each other.
Core drill.
A positioning shaft shape whose base end is attached to the front end of the shaft portion, extends forward through the center of the cylindrical portion of the blade body portion, and has a distal end protruding forward of the cutting edge of the blade body portion. Further comprising a member,
The shaft-shaped member is
A communication passage that communicates the outer surface of the dust suction passage with the outer surface is provided.
The core drill according to claim 1.
The shaft-shaped member is
It is a center pin that is detachably attached to the front end of the shaft portion and can be expanded and contracted in the axial direction.
The core drill according to claim 2.
The shaft-shaped member is
It is a center drill that opens a center hole in the drilling object.
The core drill according to claim 2.