JPH07118977B2 - Processing tool for large diameter holes - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a working tool used for forming a large-diameter hole required for piping of an air conditioner on a wall surface of a building frame.

[0002]

2. Description of the Related Art FIG. 4 is a side sectional view showing a conventional working tool 100. This processing tool 100 is a center drill 1
32, a central body portion 131, and a shank 133 (a portion to be chucked by an electric drill or the like) with respect to the tool shaft body 130, along the annular end portions on both sides in the longitudinal direction so as to surround the center drill 132. Many cutting blades 1
A cylindrical hole drilling cylinder 110 provided with 11 is held.

The hole forming cylinder 110 can be easily attached to and detached from the tool shaft body 130 when the cutting blade 111 is damaged. The structure for that is as follows. That is, the central body portion 131 of the tool shaft body 130 has a stepped structure including the small diameter portion 135 and the large diameter portion 136. Of these, the small diameter portion 135 has a disk-shaped cylindrical holder 1
20 is inserted. The tube holder 120 has a boss 122 having a central hole 123, a flange 121 protruding around the boss 122, and a flange 121 protruding from the flange 121 toward the hole processing cylinder 110. The expansion / contraction wheel portion 124 is capable of contacting the peripheral surface. The expansion / contraction ring portion 124 is provided with a large number of slits 125 extending from the projecting end to the flange portion 121 along the axis of rotation at a predetermined pitch over the entire circumference. Also,
A small diameter portion 135 is provided on the central body 131 of the tool shaft body 130.
A threaded portion 134 is provided at the end on the side, and the taper disk 1 having a threaded hole 141 at the center thereof is provided in this threaded portion 134.
40 is screwed together. The outer peripheral surface of the taper disk 140 is literally formed into a taper surface having a smaller diameter toward the cylinder holder 120 side, and is in contact with the inner peripheral surface of the expansion / contraction ring portion 124.

Therefore, if the tool shaft body 130 is rotated in the screw tightening direction while holding the cylinder holder 120 in a non-rotatable state, the taper disk 140 will be rotated.
And the expansion / contraction ring portion 124 is expanded, and the inner surface of the hole-machining cylinder 110 is pressed around the entire circumference, and the overall assembly relationship is fixed.
On the contrary, if the tool shaft body 130 is rotated in the loosening direction of the screw, the entire shaft can be loosened.

[0005]

The rotation direction when the tool shaft body 130 is tightened with respect to the cylinder holder 120 (taper disk 140) is the rotation direction when the machining tool 100 is used to form a large-diameter hole. It must be the same as (the direction of rotation of an electric drill). This is of course to prevent loosening of the screws during use. Therefore, while the machining tool 100 is being used, the tool shaft body 130 is further tightened, and then it becomes extremely difficult to loosen the entire body. That is, when the cutting blade 111 is damaged or the like, there is a problem that it takes a lot of time and labor to remove the hole forming cylinder 110 from the tool inner shaft body 130 to change its direction or replace it. In particular, when cutting chips or the like are caught between the respective abutting surfaces of the tool shaft body 130 and the taper disk 140 or the respective abutting surfaces of the cylindrical holder 120, the whole may not be able to be separated. It was

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a machining tool for a large-diameter hole in which the hole machining cylinder can be reliably and quickly attached to and detached from the tool shaft body. To do.

[0007]

In order to achieve the above object, the present invention takes the following technical means. That is, in the method according to the present invention, the center drill, the center barrel, and the shank are provided on one axis along the axis of rotation, and the tool core is held by the periphery of the center barrel of the tool core. A large-bore hole machining tool having a disk-shaped cylinder holder and a cylindrical hole-machining cylinder held by the cylinder holder in a state of enclosing a center drill of the tool shaft body, wherein a central body portion of the tool shaft body is provided. Has a thread portion formed on the outer peripheral surface on the side of the center drill, and the cylinder holder is formed with a boss portion screwed into the thread portion of the tool shaft body and a boss portion formed orthogonally around the boss portion to form a hole forming cylinder. It has a flange part that fits and holds one end, and the hole forming cylinder is provided with a large number of cutting blades along the annular ends on both sides, and the hole part is formed in the flange part of the cylinder holder. An outer diameter that can be inscribed in the cylinder Alternatively, the expansion / contraction ring portion formed with slits in the same direction as the rotation axis is provided at a plurality of locations integrally or separately, and through holes are formed at least at two locations along the peripheral portion of the boss portion. A taper disk having a tapered outer peripheral surface capable of abutting the inner peripheral surface of the expansion / contraction wheel portion and an insertion opening for a tool shaft body in the central portion is arranged so that the small diameter end surface side faces the cylinder holder. The taper disk has a small-diameter end surface side, which is integrally or separately provided with an encircling piece having an arc-shaped cross section which projects from each through hole formed in the flange portion of the cylinder holder along the periphery of the boss portion. The outer peripheral surface of each of the surrounding pieces is characterized in that a screw centering on the rotation axis is engraved so that the nut member is screwed.

[0008]

According to the present invention, when the taper disc is fitted toward the expansion / contraction ring portion provided integrally with or separately from the cylinder holder,
The surrounding piece protruding from the taper disk penetrates the flange portion of the cylinder holder and is arranged along the periphery of the boss portion of the cylinder holder. When the nut member is screwed into this surrounding piece and tightened, the taper disk is pulled toward the cylinder holder, expanding the expansion / contraction ring part, and the inner peripheral surface of the hole-processed cylinder fitted and held on the outer peripheral part. Will be pressed all around. That is, this fixes the hole forming cylinder. As a structure different from this, the central body portion of the tool shaft body is screwed into the boss portion of the cylinder holder to fix both of them.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. 1 and 2 show a first embodiment of a machining tool 1 according to the present invention, in which 2 is a tool shaft body consisting of a center drill 3, a central body portion 4 and a shank 5, and 10 is hole machining. It is a cylinder. The center body portion 4 of the tool shaft body 2 has a stepped structure having a small diameter portion 6 and a large diameter portion 7, and a large number of hole forming cylinders 10 are provided along the annular end portions on both sides in the longitudinal direction. Regarding that it has the cutting blade 11 of the above, except for the dimensional length of each part, the conventional processing tool 100 (see FIG. 4)
Is almost the same as.

In this machining tool 1, as a structure for holding the hole machining cylinder 10 with respect to the tool shaft body 2, the cylinder holder 20 and the taper disk 40 including the tool shaft body 2 are as follows. . First, in the tool shaft body 2, the threaded portion 8 is the entire length of the small diameter portion 6 that is closer to the center drill 3 in the central body portion 4.

The tube holder 20 has a tool center shaft 2 at the center thereof.
It has a boss portion 22 having a threaded hole 23 formed therethrough that is screwed into the threaded portion 8 and a flange portion 21 formed around the boss portion 22 so as to extend orthogonally. Flange 21
An expansion / contraction ring portion 24 that can come into contact with the inner peripheral surface of the hole forming cylinder 10 is integrally provided to the hole forming cylinder 10 side. The expansion / contraction ring portion 24 is provided with a large number of slits 25 extending from the projecting end to the flange portion 21 along the rotation axis center at a predetermined pitch over the entire circumference thereof. Each tongue piece 26 that remains between the slits 25 has a recess 27 formed in the outer peripheral surface in the middle thereof.
The elastic rocking easily occurs along the radial direction.
The inner surface of each tongue piece 26 is inclined so that the tongue piece 26 becomes thinner toward the tip end side. On the other hand, in the flange portion 21, through-holes 28 each having an arc shape are formed at two opposite positions of the peripheral portion around the boss portion 22.

The taper disc 40 has a small diameter end face 42 having a diameter capable of being fitted in the expansion / contraction ring portion 24 of the cylinder holder 20,
A large-diameter end surface 43 formed to be slightly smaller than the inner diameter of the hole-machining cylinder 10 and having a tapered outer peripheral portion, the central portion of which penetrates between both end surfaces 42, 43. A central hole 41 is formed. A cylindrical part 50 is fitted into the central hole 41. This part 50
Is made of a pipe material and has a collar portion 46 formed at one end side thereof, and at the other end portion thereof, a surrounding piece 4 having an arcuate cross section protruding in a bifurcated shape.
The notches 48 facing each other are formed so as to leave 7 remaining, and the screws 49 for screwing the nut member 30 are further formed on the outer peripheral surfaces of the surrounding pieces 47. Each surrounding piece 47 has such a length and shape as to pass through each through hole 28 formed in the flange portion 21 of the cylinder holder 20 and follow the outer peripheral surface of the boss portion 22. The pipe hole of the part 50 serves as an insertion port 45 for the tool shaft body 2. It should be noted that the reason why the parts 50 are fitted into the taper disk 40 is to consider the ease of processing of both parts, and the surrounding piece 47 and the insertion port 4 are used as the taper disk 40.
You may make it integrally formed in the form provided with 5.

The tool shaft body 2, the cylinder holder 20, the hole-machining cylinder 10, the taper disk 40 (part 50) thus constructed.
In order to assemble the machining tool 1 using
The taper disk 40 (with the parts 50 fitted therein) is arranged such that the small-diameter end surface 42 side faces the tube holder 20, and each surrounding piece 4
7 is inserted into the cylinder holder 20 in such a manner as to pass through the through hole 28 of the cylinder holder 20, and the nut member 30 is lightly screwed into the surrounding piece 47 which is arranged along the periphery of the boss portion 22 of the cylinder holder 20. So that they do not separate. Then, with the center drill 3 passing through the screw hole 23 of the cylinder holder 20 toward the insertion opening 45 of the taper disk 40, the screw portion 8 of the tool shaft body 2 is screwed into the screw hole 23 of the cylinder holder 20. And tighten them firmly to fix them. Further, one end portion of the hole forming cylinder 10 is fitted and held around the expansion / contraction ring portion 24 and the taper disk 40 of the cylinder holder 20. At this time, the cutting blades 11 of the hole forming cylinder 10 are fitted into the slits 25 of the expansion / contraction wheel portion 24 correspondingly, and the provisional rotation of the cylinder holder 20 and the hole forming cylinder 10 is performed. The stopping action and the positioning action and the protecting action of the cutting blade 11 are obtained. After doing this, the cylinder holder 20
The nut member 30 is tightened in the tightening direction of the screw while the (actually, the hole forming cylinder 10) is held in a non-rotatable state. As a result, the taper disk 40 is attracted to the tube holder 20 and spreads the expansion / contraction ring portion 24, whereby the inner surface of the hole-machining tube 10 is pressed all around, and the overall assembly relationship is fixed. It

FIG. 3 is an exploded view of the main parts according to the second embodiment of the present invention. The difference from the first embodiment is that in the cylinder holder 20, a flange portion 21 and an expansion / contraction ring portion 24 are provided. Is formed as a separate body.
The expansion / contraction ring portion 24 is a split ring in which a slit 25 is formed at one location on the outer peripheral portion so as to have a C-shaped planar shape, and the inner peripheral surface thereof has a large inner diameter on the taper disk 40 side. Is formed in a tapered surface such that the inner diameter on the cylinder holder 20 side is small. The expansion / contraction ring portion 24 can have a straight inner surface, or can be divided into a plurality of arc-shaped pieces by providing a plurality of slits 25. The other structure and operation of the second embodiment are the same as those of the first embodiment, and therefore, the same reference numerals are given to the respective parts and the description thereof will be omitted.

[0015]

According to the present invention, which has the above-mentioned structure, the tool shaft body and the tube holder are fixed to each other by screw fitting, while the taper disk penetrates the tube holder from the taper disk. The nut member is screwed to the surrounding piece that protrudes to the position so that the nut member is pulled toward the expansion / contraction ring portion. That is, since the tool shaft and the taper disk do not have a direct screwing structure, it is never difficult to attach and detach the hole forming cylinder by using this processing tool. Therefore, the work for reversing or replacing the mounting direction of the hole forming cylinder can be performed reliably and quickly.

[Brief description of drawings]

FIG. 1 is a side sectional view showing a first embodiment of the present invention.

FIG. 2 is a partially crushed perspective view showing the main part of FIG. 1 in an exploded manner.

FIG. 3 is an enlarged side sectional view showing an exploded main part of the second embodiment of the present invention.

FIG. 4 is a side sectional view showing a conventional processing tool.

[Explanation of symbols]

 1 Processing Tool 2 Tool Middle Shaft 3 Center Drill 4 Central Body 5 Shank 8 Thread 10 Hole Machining Tube 11 Cutting Blade 20 Tube Holder 21 Flange 22 Boss 24 Expansion / contraction Ring 25 Slit 28 Through Hole 30 Nut Member 40 Taper Disk 42 small diameter end face 45 insertion port 47 enclosing piece 49 screw

Claims (1)

[Claims] 1. A tool center shaft body comprising a center drill, a center body part, and a shank provided on a single axis along the axis of rotation, and a disk-shaped tube held by the peripheral part of the center body part of the tool center shaft body. A large-diameter hole machining tool having a holder and a cylindrical hole-machining cylinder held by the cylinder holder in a state of enclosing the center drill of the tool shaft body, wherein a center drill is provided in the center barrel of the tool shaft body. A threaded portion is formed on the outer peripheral surface on the side of the hole holder, and the cylinder holder is formed so as to extend perpendicularly around the boss portion screwed into the threaded portion of the tool shaft and to fit one end portion of the hole machining cylinder. The hole forming cylinder is provided with a large number of cutting blades along the annular ends on both sides, and the flange part of the cylinder holder is inscribed in the hole forming cylinder. Has an outer diameter that can be obtained at one or more locations on the outer periphery The expansion / contraction ring portion formed with a slit in the same direction as the rotation axis is integrally or separately provided, and through holes are formed at least at two positions along the peripheral portion of the boss portion. A taper disk having a tapered outer peripheral surface capable of abutting the inner peripheral surface of the ring portion and an insertion opening for the tool shaft body in the central portion is fitted so that the small diameter end surface side faces the cylinder holder. , On the small-diameter end surface side of the taper disk, integrally or separately provided with an encircling piece having an arc-shaped cross section that protrudes from each through hole formed in the flange portion of the cylinder holder along the periphery of the boss portion. A machining tool for a large-diameter hole, wherein a screw centering on the rotation axis is engraved on the outer surface of the surrounding piece so that a nut member can be screwed.