JP2005280244A - Drill tool - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a drill tool capable of cutting the inner peripheral surface of a hole to easily form a deep recessed part. <P>SOLUTION: The drill tool 10 used is characterized in that an annular guide plate 35 freely revolvable with respect to a long rod-shaped shank 20 is mounted on the outer periphery on the midway part of the shank 20 and a head 11, of which the diameter is larger than that of the shank 20 is provided to the leading end of the shank 20, that one or a plurality of ribs 15a, 15b and 15c formed along the peripheral direction of the head 11 are provided to the side surface of the head 11 in a protruded state, and that cutting blades 16a, 16b and 16c are arranged to protruded end edges of the ribs 15a, 15b and 15c in a protruded state. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a drill tool for cutting a part of an inner peripheral surface of a hole formed in a casing such as concrete.

  As a method of constructing anchors, deformed steel bars, etc. on a concrete frame, etc., a drill hole or other drilling machine is used to form a pilot hole, and after cleaning, an adhesive such as mortar or resin is injected into the pilot hole. However, a method of inserting and fixing a bar is widely used. At this time, if a part of the inner peripheral surface of the lower hole is cut and roughened, the adhesive force of the adhesive to the inner peripheral surface of the lower hole is increased. Examples of the roughening jig for this purpose include the following.

In Patent Document 1, a blade is arranged so that it can project and retreat in the radial direction of the rotating body, and a wedge-shaped member is brought into contact with the back of the blade, whereby the blade tip is pressed against the inner peripheral surface of the hole. A hole expanding device is described.
Patent Document 2 describes a jig provided with one or more cutting tips on one axial half surface of a rod-shaped main body.
Patent Document 3 includes a series of cutting elements arranged along the longitudinal direction of the shaft so as to protrude radially from the shaft, and a pair of cutting elements adjacent to each other on the side close to the mounting end. A drill tool is described in which the spacing is greater than the spacing between a pair of adjacent cutting elements on the side away from the mounting end.
In the tools disclosed in Patent Documents 2 and 3, since the cutting tip is disposed on one side of the tool body, when the tool body is rotated, the rotating shaft swings, and the cutting tip is the inner peripheral surface of the hole. Is supposed to cut.
Patent Document 4 describes a construction cutting bit in which a plurality of cemented carbide tips made of a plurality of cemented carbide or diamond are projected along a spiral track on an outer circumferential surface having substantially the same diameter as the inner wall surface of a prepared hole. Yes.
JP 60-247507 A Japanese Patent Laid-Open No. 3-182305 JP 10-44135 A Japanese Patent No. 3404301

However, in the case of the hole expanding device described in Patent Document 1, the mechanism for moving the blade back and forth with respect to the inner peripheral surface of the hole is complicated, and it is inferior in durability, difficult to manufacture, and expensive.
With tools such as those described in Patent Documents 2, 3, and 4, it is possible to cut only the protruding height of the tip at most, and to make the depth of the recess formed on the inner peripheral surface of the hole too deep. Can not. For this reason, when the hole has a large diameter (for example, a diameter of 90 mm), if the concave portion is too shallow, the effect of improving the strength for fixing the bar material such as the anchor becomes low. However, if the chip is protruded too high, the impact applied to the chip increases, and the durability may deteriorate.

  This invention is made | formed in view of the said situation, and makes it a subject to provide the drill tool which can form the deep recessed part easily by cutting the internal peripheral surface of a hole.

In order to solve the above-mentioned problems, the present invention provides an annular guide plate that is rotatable with respect to the shank on the outer periphery of a middle portion of a long rod-shaped shank. A head having a larger diameter is provided, and one or a plurality of annular ribs formed along the circumferential direction of the head are provided on the side surface of the head, and a cutting blade protrudes from the protruding edge of these ribs. Provided is a drill tool characterized by being arranged.
In the drill tool, the cutting blade is preferably arranged so that the angle along the circumferential direction of the head is shifted for each rib.
Moreover, it is also possible to employ a configuration in which the height of the cutting blade from the central axis of the shank increases from the proximal end of the head to the distal end for each rib.
The head is preferably detachable from the shank.

According to the drill tool of the present invention, by bringing the guide plate into contact with the inner peripheral surface of the lower hole, the shank is inclined with respect to the lower hole while rotating the shank with the guide plate as a bearing, and the cutting blade is moved into the hole. It becomes possible to cut this by making pressure contact with the peripheral surface. Therefore, it is possible to easily cut the inner peripheral surface of the prepared hole deeper than the protruding height of the cutting blade.
Since the head has a larger diameter than the shank, it is easy to swing the head using the guide plate as a fulcrum. Moreover, since the shank can be formed thinner than the hole diameter, the jig can be reduced in weight. Since the gaps between the ribs are concave grooves, it is easy to discharge chips.
When installing anchor bolts or the like on the housing, roughening of the pilot holes can be performed efficiently. A mechanism for projecting and retracting the cutting blade with respect to the tool body is unnecessary, and the structure can be simplified and the durability can be improved.
Even if the hole has a large diameter (for example, a diameter of about 90 mm or more), a sufficiently deep recess can be formed, and roughening of the prepared hole can be effectively performed when constructing an anchor bolt or the like. it can.

The present invention will be described below with reference to the drawings based on the best mode.
Fig.1 (a) is drawing which shows the example of 1 form of the drill tool of this invention. FIG. 1B is a partially cutaway cross-sectional view showing an enlarged front end side of the drill tool of the present embodiment. FIG. 2 is a cross-sectional view illustrating the front end side of the head from a cut surface along the line II-II in FIG.
Fig.3 (a) is drawing which shows an example of the use condition of the drill tool of this embodiment. FIG.3 (b) is drawing which shows an example of a mode that the recessed part was formed in the internal peripheral surface of a hole by the operation | work shown to Fig.3 (a).
Fig.4 (a) is drawing which shows the 2nd example of the use condition of the drill tool of this embodiment. FIG. 4B is a drawing showing a second example in which a recess is formed on the inner peripheral surface of the hole by the operation shown in FIG.

  As shown in FIGS. 1 and 2, the drill tool 10 according to the present embodiment includes an elongated rod-shaped shank 20, an annular guide plate 35 attached to the outer periphery of the middle portion of the shank 20, and the shank 20. And a head 11 having a diameter larger than that of the shank 20 provided at the tip of the head. The head 11, the shank 20, and the guide plate 35 can be made of a rigid metal or the like.

  Here, the shank 20 is configured by connecting a first shank 21 on the distal end side (side on which the head 11 is provided) and a second shank 31 on the proximal end side (side on which the rotary tool 40 is connected). Yes. On the base end 31b side of the second shank 31, a tool connecting portion 37 (here, a hexagonal bar-like joint) for connecting a rotary tool 40 such as a hammer drill is provided.

  A plurality of annular ribs 15 a, 15 b, and 15 c formed along the circumferential direction of the head 11 are projected from the side surface of the head 11. Further, cutting edges 16a, 16b, and 16c are disposed so as to protrude from the protruding edges of the ribs 15a, 15b, and 15c. Between the annular ribs 15 a, 15 b, 15 c, the outer peripheral surface of the head 11 is an annular concave groove 14.

Here, a plurality of annular ribs 15a, 15b, and 15c are provided between the distal end portion 11a and the proximal end portion 11b of the head 11. Here, the number of the annular ribs 15a, 15b, 15c is three, but is not particularly limited in the present invention. Further, the number of the annular ribs can be one.
In the drawings and the following description, the reference numerals of the annular ribs are distinguished as 15a, 15b, and 15c in order from the distal end portion 11a side to the proximal end portion 11b side of the head 11 for convenience.
In this embodiment, the diameters of the annular ribs 15a, 15b, and 15c are the same, and the diameters of the annular ribs 15a, 15b, and 15c are perforated in the casing 1 such as concrete as shown in FIG. The diameter is selected to be smaller than the diameter (inner diameter) of the prepared lower hole 2.

The ratio of the width of the annular ribs 15a, 15b, 15c and the width of the concave groove 14 is not particularly limited. For example, when the annular groove 3 is formed step by step as shown in FIG. It is preferable to make the ratio of the width of 15a, 15b, 15c: the width of the concave groove 14 relatively small.
In addition, as shown in FIG. 4, when the annular groove 3 cut by the respective annular ribs 15a, 15b, and 15c is connected to form a larger diameter enlarged portion 4, the annular ribs 15a, 15b, and 15c It is preferable to make the ratio of width: width of the concave groove 14 relatively large.

As the cutting blades 16a, 16b, and 16c, cutting tips made of, for example, cemented carbide can be used. In the drawings and the following description, for the sake of convenience, the sign of the cutting edge is directed from the distal end part 11a side of the head 11 to the proximal end part 11b side so as to correspond to the sign of the annular ribs 15a, 15b, 15c. They were distinguished as 16a, 16b, and 16c in order.
As shown in FIG. 2, a plurality of cutting blades 16a, 16b, 16c are implanted at equal intervals (four in the illustrated example at intervals of 90 °) for each of the ribs 15a, 15b, 15c. The cutting blades 16a, 16b, and 16c are arranged so as to be shifted by 30 ° in the circumferential direction of the annular ribs 15a, 15b, and 15c between adjacent ribs (15a and 15b, 15b and 15c). That is, the cutting edges 16a, 16b, and 16c are all arranged so that the angles along the rotation direction are shifted. Thereby, when the drill tool 10 is rotated, the cutting blades 16 a, 16 b, and 16 c come into contact with the inner peripheral surface of the lower hole 2 one by one, and the rotary tool 40 transmitted through the shank 20. It is possible to increase the cutting efficiency by effectively using the driving force.

A first shank insertion hole 12 is formed in the head 11 so as to penetrate between the distal end side and the proximal end side. An insertion portion 22 that can be inserted into the first shank insertion hole 12 of the head 11 is formed on the distal end 21 a side of the first shank 21. The insertion portion 22 is formed with a male screw portion 22a that is screwed into the female screw portion 12a on the first shank insertion hole 12 side. The head 11 and the first shank 21 can be connected by screwing both screw portions 12a and 22a.
As shown in FIGS. 1 and 2, a pair of head end 11b and the outer periphery of the first shank 21 are exposed to a position where the head 11 and the first shank 21 are connected to each other. Planar notches 13 and 23 are formed. Thereby, when fastening or loosening the screw, the head 11 and the first shank 21 can be sandwiched by bringing a tool (not shown) into contact with the flat cutout portions 13 and 23 and holding the head 11 and the first shank 21 together. Can be easily carried out.

A second shank insertion hole 24 into which the insertion portion 32 of the distal end 31a of the second shank 31 can be inserted is formed on the base end 21b side of the first shank 21. The insertion portion 32 of the second shank 31 is formed with a male screw portion 32a that is screwed into the female screw portion 24a on the second shank insertion hole 24 side. The 1st shank 21 and the 2nd shank 31 can be connected now by screwing of both screw parts 24a and 32a.
As shown in FIG. 1, the first shank 21 and the second shank 31 are exposed on the outer periphery on the base end 21 b side and the front end 31 a side of the second shank 31 in a state where the first shank 21 and the second shank 31 are connected. Further, a pair of flat cutout portions 25 and 33 are formed respectively. Thus, when fastening or loosening the screws, the first shank 21 and the second shank 31 can be sandwiched by bringing the tool (not shown) into contact with the flat cutout portions 25 and 33 and affixing the first shank 21 and the second shank 31. The detaching operation with the two shanks 31 can be easily performed.

  The screw tool 12a and 22a connected to the head 11 and the first shank 21 and the thread winding direction in the screw parts 24a and 32a connected to the first shank 21 and the second shank 31 are rotated by the rotary tool 40. In order to prevent the screw parts 12a, 22a, 24a, and 32a from being loosened, the screw is tightened by turning in the rotational direction of the drill tool 10.

A flange portion 34 projects from the second shank 31 with a gap from the base end 21b of the first shank 21 in a state where the first shank 21 and the second shank 31 are connected.
The guide plate 35 is an annular member having a through hole 35a. The guide plate 35 is rotatably held with respect to the shank 20 by being sandwiched between the base end 21b of the first shank 21 and the flange portion 34 of the second shank 31 with some clearance. Yes.
The inner peripheral surface of the through hole 35a of the guide plate 35 and the outer peripheral surface of the sliding portion 36 (between the flange portion 34 and the screw portion 32a) of the second shank 31 that is in contact with the inner surface of the through hole 35a are smooth by a metal receiver. It is designed to rotate.

Next, the operation of the drill tool 10 of this embodiment will be described.
As shown in FIG. 1, the drill tool 10 is connected to the rotary tool 40 via the tool connecting portion 37, and as shown in FIG. 3, the drill tool 10 is inserted into the pilot hole 2 formed in the housing 1 on the head 11 side. Insert from. Further, the drill tool 10 is rotated by the rotary tool 40 described above while the guide plate 35 is brought into contact with the inner peripheral surface of the lower hole 2. At this time, since the guide plate 35 serves as a bearing, the shank 20 can smoothly rotate in the through hole 35 a of the guide plate 35 even if the guide plate 35 stops with respect to the lower hole 2.

By tilting the shank 20 with respect to the lower hole 2 using the guide plate 35 as a fulcrum, the cutting edges 16a to 16c can be pressed against the inner peripheral surface of the lower hole 2 to cut the inner peripheral surface of the lower hole 2. . By swinging the tip of the head 11 so as to swing, the inner peripheral surface of the lower hole 2 can be cut evenly in the circumferential direction. Thus, cutting deeper than the protruding height of the cutting blades 16a to 16c can be easily performed.
For example, in FIG. 3B, by gradually shortening the insertion length of the drill tool 10 from the bottom surface 2a of the lower hole 2 toward the opening 2b, a large number of annular grooves 3 are formed on the inner peripheral surface of the lower hole 2. It can be formed step by step.

As a method of constructing an anchor or deformed steel bar or the like in this lower hole, after cleaning the lower hole, insert the bar into this lower hole and insert mortar or mortar into the gap between the inner peripheral surface of the lower hole and the bar. It can be carried out by injecting and fixing an adhesive such as resin. In some cases, a rod is inserted and fixed after injecting an adhesive such as mortar or resin into the prepared hole.
By forming a large number of annular grooves 3 in this way, if the inner peripheral surface of the lower hole is roughened, the adhesion of the adhesive to the inner peripheral surface of the lower hole is increased, and the rod is made stronger. Can be constructed.

4 (a) and 4 (b), the head 11 is also swung up and down to connect the annular grooves 3 cut by the respective annular ribs 15a, 15b, and 15c, so that the larger expansion is achieved. In the case of forming the diameter portion 4, it is preferable that the ratio of the width of the annular ribs 15 a, 15 b, 15 c: the width of the groove 14 is relatively large.
In this case, it is preferable that the gap between the base end 21 b of the first shank 21 and the flange portion 34 of the second shank 31 is made large so that the shank 20 can easily move with respect to the guide plate 35.

According to the drill tool of this embodiment, the shank can be tilted with respect to the pilot hole while rotating with the guide plate provided in the middle of the shank as a fulcrum. Thereby, it is possible to easily cut the inner peripheral surface of the prepared hole deeper than the protruding height of the cutting blade.
Since the head has a larger diameter than the shank, the head can be easily swung with the guide plate as a fulcrum. Moreover, since the shank can be formed thinner than the hole diameter, the jig can be reduced in weight. It is also easy to discharge chips through the concave grooves between the ribs.
When installing anchor bolts or the like on the housing, roughening of the pilot holes can be performed efficiently. A mechanism for projecting and retracting the cutting blade with respect to the tool body is unnecessary, and the structure can be simplified and the durability can be improved.

  Since a plurality of cutting blades are protruded and arranged at the protruding edge of each rib, when forming the annular groove, the plurality of cutting blades are sequentially pressed against the same part of the inner peripheral surface of the lower hole, thereby further improving the cutting efficiency. Can be high.

Since the head can be attached to and detached from the shank, work with various conditions by replacing the head with an appropriate one according to the diameter of the pilot hole and the size of the recess (width, depth, etc.) And efficient work is possible. Further, even when the cutting blade is worn or broken, the head can be replaced and used continuously.
Since the guide plate can also be replaced by removing the connection between the first shank and the second shank, it can be replaced with an appropriate guide plate according to the diameter of the pilot hole.

Next, a modified drill tool of the present invention will be described with reference to FIG.
Fig.5 (a) is drawing which shows the drill tool of a modification. FIG.5 (b) is drawing which shows an example of the recessed part formed in the internal peripheral surface of a hole using the drill tool shown to Fig.5 (a).
5A and 5B, the same reference numerals as those used in FIGS. 1 to 4 indicate the same or similar configurations as those shown in FIGS. Is omitted.

In the drill tool 10 shown in FIG. 5, the radii of the annular ribs 15 a, 15 b, and 15 c are larger toward the distal end portion 11 a side than the proximal end portion 11 b side of the head 11. Thereby, the turning radius of the cutting blades 16 a, 16 b, 16 c around the turning axis of the shank 20 increases from the base end of the head 11 toward the tip.
In order for the head 11 to be easily inserted into the lower hole 2, the radii of the annular ribs 15a, 15b, and 15c are all larger than the inner diameter of the lower hole 2 at the stage of the straight hole before cutting the inner peripheral surface. It is desirable to make it smaller.

  Even when the drill tool 10 configured as described above is used, the cutting blades 16 a to 16 c are pressed against the inner peripheral surface of the lower hole 2 by tilting the shank 20 with respect to the lower hole 2 with the guide plate 35 as a fulcrum. Thus, the inner peripheral surface of the lower hole 2 can be cut. By swinging the tip of the head 11 so as to swing, and further swinging the head 11 up and down, the inner peripheral surface of the lower hole 2 is cut evenly in the circumferential direction, and the annular groove 3 generated by the cutting is further connected, As shown in FIG. 5, a tapered diameter-enlarged portion 5 having a large diameter on the bottom surface 2 a side of the lower hole 2 can be formed.

Although the present invention has been described based on the best mode, the present invention is not limited to the above-described best mode, and various modifications can be made without departing from the gist of the present invention.
For example, the structure in which the guide plate is rotatably mounted in the middle part of the shank is not limited to the metal receiver as in the above embodiment, and a bearing having another structure can also be adopted. It is.

  INDUSTRIAL APPLICABILITY The present invention can be used for cutting a part of the inner peripheral surface of a hole formed in a casing such as concrete. For example, when adhesively fixing an anchor bolt, a steel bar, a pile, etc., it can be used for roughening the inner peripheral surface of the prepared hole.

(A) It is drawing which shows the example of 1 form of the drill tool of this invention. (B) It is the fragmentary sectional view which expanded and showed the front end side of the drill tool shown to Fig.1 (a). It is sectional drawing which illustrated the front end side of the head from the cut surface which follows the II-II line | wire of FIG.1 (b). (A) It is drawing which shows an example of the use condition of the drill tool shown in FIG. (B) It is drawing which shows an example of a mode that the recessed part was formed in the internal peripheral surface of a hole. (A) It is drawing which shows the 2nd example of the use condition of the drill tool shown in FIG. (B) It is drawing which shows the 2nd example of a mode that the recessed part was formed in the internal peripheral surface of a hole. (A) It is drawing which shows the modification of the drill tool of this invention. (B) It is drawing which shows an example of the recessed part formed in the internal peripheral surface of a hole using the drill tool shown to Fig.5 (a).

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Drill tool, 11 ... Head, 15a-15c ... Rib, 16a-16c ... Cutting blade, 20 ... Shank, 35 ... Guide plate.

Claims (4)

  An annular guide plate that is rotatable with respect to the shank is mounted on the outer periphery of a middle portion of the long shank, and a head having a diameter larger than that of the shank is provided at the tip of the shank. One or a plurality of annular ribs formed along the circumferential direction of the head are provided on the side surface of the head, and a cutting blade is projected from the protruding edge of these ribs. .   The drill tool according to claim 1, wherein the cutting blade is arranged such that an angle along a circumferential direction of the head is shifted for each rib.   3. The drill tool according to claim 1, wherein a height of the cutting blade from a central axis of the shank increases from a proximal end to a distal end of the head for each rib.   The drill tool according to any one of claims 1 to 3, wherein the head is detachable from the shank.

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