JP2016037988A - Expansion anchor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an anchor capable of efficiently cutting hole at an item to be cut and that is fixed positively to the item to be cut.SOLUTION: An expansion anchor 10 comprises an anchor tube 12 and an anchor core 14 fitted and inserted into the anchor tube 12. The anchor tube 12 has a plurality of cut holes 24 formed to be divided and expanded by a slit punched in an axial direction of the anchor tube 12. The extremity end of slit part of one cut hole is formed to have an acute end and the extremity ends of slits at two cut holes adjacent to the one cut hole are cut and recessed, the extremity end of the slit part of one cut hole is exposed and formed to cut the item to be cut, the anchor tube 12 is struck into an axial line direction of the anchor core 14 to expand the cut hole part along the outer circumferential surface of the anchor core 14 to bite into the item to be cut.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an anchor, and more particularly, to an expanded anchor used for fixing a vessel to a frame (base material) such as a concrete frame.

Conventionally, as an anchor used for fixing an object to a housing while being fixed to the housing by inserting into a pilot hole drilled in a housing such as concrete and expanding a tip portion (expansion portion), for example, a patent There are those described in Documents 1 and 2.
The anchor described in Patent Document 1 has an anchor hole 2 formed in an existing concrete structure 1, and the hole wall is enlarged and cut to form an enlarged portion 2 a having an upper concavity. And a taper nut 15 formed with a tapered portion 15a having a constriction in the upper part thereof screwed to the screw rod 14 and the taper portion 15a of the taper nut 15 to be pushed open. The expansion piece 17 is inserted into the lower part of the ring body 19 with an anchor fitting made of a diameter-enlarging metal fitting 16 formed in a skirt shape, and the expansion piece 17 is opened by pushing the diameter-expansion metal fitting 16 with a jig. It is comprised so that it may engage with the enlarged diameter part 2a of a wall.
The anchor described in Patent Document 2 has an anchor rod (1) having a head portion (2) that expands in one direction at one end, and an expanded piece (6) separated from each other by an axial slit (5). ), And the slit is provided from the plastic hinge (4) to the front free end (7) of the sleeve (3), and the sleeve (3) and the anchor rod (1) are moved relative to each other. In the expansion anchor in which the expansion pieces (6) are pushed outward in the radial direction by the above, at least one groove-like depression (8 or 9) is provided in each expansion piece (6). A dent extending to the region of the front free end (7), extending over at least a portion of the axial length (l) of the spreading piece (6) and parallel to the axis (A) of the sleeve Inclined with respect to the straight line (G), the three (3) the distance from the straight line of the outlet (G) in the region of the front free end (7) (a) is characterized by being made larger in.

Japanese Patent No. 3636632 Japanese Patent No. 4068712

Mechanical anchors such as those described in Patent Documents 2 and 2 are usually provided with a slit in the anchor body and the like, and an expanded portion that expands in a skirt shape. The anchor body is inserted into an anchor hole drilled in a concrete structure and then expanded. The part is expanded in the hole and fixed by this frictional force.
However, with regard to mechanical anchors, it is possible to efficiently drill a workpiece such as concrete, and the mechanical anchor can be securely fixed to a workpiece such as concrete and come off or slip. No such anchor is desired.

  This invention is made | formed in view of the said situation, Comprising: It makes it a subject to provide the anchor which can be drilled to a workpiece efficiently and is firmly fixed to a workpiece.

The spread anchor according to the present invention includes an anchor tube and an anchor core that is inserted into the anchor tube.
The anchor tube includes a head portion that expands in a direction crossing the axial direction at an end portion into which the anchor core is fitted,
The head portion has a plurality of drilling portions formed so as to be divided and expanded by a slit portion drilled in the axial direction of the anchor tube,
The tip on the slit side of one of the drilling portions constituting the drilling portion is formed sharply,
The tip on the slit side of the two drilling portions adjacent to each other with the slit portion sandwiched between the one drilling portion is cut out,
The tip on the slit side of the one hole portion is exposed toward the direction of rotating the anchor tube at the time of cutting, and is formed so as to cut the workpiece.
The slit is formed such that the shavings produced when being cut are guided in a direction opposite to the driving direction along the slit,
The anchor tube is driven so as to be driven in the axial direction of the anchor core, the drilling portion is expanded along the outer peripheral surface of the anchor core, and is formed so as to bite into the work piece.
It is a spread anchor.
The expansion anchor according to claim 2 is:
A sharpened portion is formed in a region where the one hole portion intersects or is orthogonal to the edge on the slit side and the lower edge,
The front end portion where the slit side edge and the lower end edge intersect with each other so that the two hole portions adjacent to each other across the slit expose the outer region at the sharpened portion of the first hole portion. The side of the cutout is cut away, and a cutout tip that is lowered toward the first slit is formed.
The expansion anchor according to claim 3 is:
Shaving powder guide in which the anchor tube guides the cutting powder produced when the workpiece is cut on the surface of the body portion opposite to the side where the anchor core is inserted into the surface opposite to the driving direction. Grooves are formed.
The expansion anchor according to claim 4 is:
The anchor core has a conical cone portion whose diameter gradually increases as it reaches a region protruding from the region inserted into the anchor tube,
The head portion of the anchor tube is formed to slide and expand on the surface of the cone portion of the anchor core.
The expansion anchor according to claim 5 is:
The anchor tube has a cylindrical shape in which the upper cylindrical body and the lower cylindrical body are integrated.
The upper cylinder is engraved with a screw on the hole wall in the through hole,
The lower cylindrical body is formed with a head portion and a slit portion having a drilling portion.

According to this invention, comprising an anchor tube and an anchor core fitted into the anchor tube,
The anchor tube includes a head portion that expands in a direction crossing the axial direction at an end portion into which the anchor core is fitted,
The head portion has a plurality of drilling portions formed so as to be divided and expanded by a slit portion drilled in the axial direction of the anchor tube,
The tip on the slit side of one of the drilling portions constituting the drilling portion is formed sharply,
The tip on the slit side of the two drilling portions adjacent to each other with the slit portion sandwiched between the one drilling portion is cut out,
The tip on the slit side of the one hole portion is exposed toward the direction of rotating the anchor tube at the time of cutting, and is formed so as to cut the workpiece.
The slit is formed such that the shavings produced when being cut are guided in a direction opposite to the driving direction along the slit,
The anchor tube is driven so as to be driven in the axial direction of the anchor core, and the hole portion is expanded along the outer peripheral surface of the anchor core so as to bite into the work piece. It is possible to provide an anchor that can be drilled and securely fixed to a workpiece.
According to the invention of claim 2,
The one drilling portion has a sharpened portion formed in a region where the edge on the slit side and the lower end edge intersect or are orthogonal to each other,
The two drilling portions adjacent to each other across the slit have an outer end portion where the edge on the slit side intersects with the lower end edge so that the outer region of the sharpened portion of the first drilling portion is exposed. Since the notch tip is formed by cutting the side surface and lowering toward the first slit side, the work can be cut efficiently.
According to the invention of claim 3,
The anchor tube guides the cutting powder produced when the work piece is cut on the surface of the body part opposite to the side where the anchor core is inserted, to the opposite side to the driving direction. Since the grooves are formed, the work can be efficiently cut without clogging with the cutting powder.
According to the invention of claim 4,
The anchor core has a conical cone portion whose diameter gradually increases as it reaches a region protruding from the region inserted into the anchor tube,
Since the head portion of the anchor tube is formed to slide and expand on the surface of the cone portion of the anchor core, it is securely fixed to the work piece.
According to the invention of claim 5,
The anchor tube has a cylindrical shape in which the upper cylindrical body and the lower cylindrical body are integrated.
The upper cylinder is engraved with a screw on the hole wall in the through hole,
Since the lower cylindrical body is formed with a head portion and a slit portion having a hole-cutting portion, it is possible to perform placement efficiently.

  The above-described object, other objects, features, and advantages of the present invention will become more apparent from the following description of embodiments for carrying out the invention with reference to the drawings.

It is a front illustration solution figure which made a part of anchor of the present invention a section. It is a bottom view solution figure of the anchor shown in FIG. It is a perspective view solution figure of the anchor shown in FIG. It is an illustration of the anchor tube of the anchor shown in FIG. It is the illustration figure solution of the anchor tube of the anchor shown in Drawing 1, (c) is a bottom view solution figure, (d) is a sectional view solution figure. It is an illustration figure of an anchor core, (a) is a top view, (b) is a front illustration solution figure, and (c) is a bottom view. It is an illustration figure which shows the construction method of an anchor. It is a front illustration solution figure which made a part of anchor set to a preceding hole into a section. It is a bottom view solution figure of the anchor set to the preceding hole. It is a perspective view solution figure which shows the usage method of the anchor shown in FIG. It is the front solution figure which made the section which shows the usage method of the anchor shown in FIG. It is a bottom view solution figure of the anchor shown in FIG. It is an illustration figure which shows the construction method of the anchor shown in FIG. It is a front illustration solution figure which made the cross section the part which shows the anchor before placement. It is the front illustration solution figure which made the section which shows the method to drive in the cross section. It is a front illustration solution figure which made the cross section the part which shows the anchor after placement. FIG. 10 is a schematic front view of a modification showing a part of the anchor before placement. It is a bottom view solution figure which shows the state before placement of the anchor of a modification. FIG. 10 is a front schematic view with a part in cross section showing a state after placement of an anchor of a modified example. It is a cross-sectional solution figure which shows the utilization method of an anchor. It is a perspective view solution figure which shows the state before placement of the anchor of a modification. It is explanatory drawing of an anchor.

An anchor according to an embodiment of the present invention will be described with reference to the accompanying drawings.
FIG. 1 is a schematic front view of a part of the anchor of the present invention, and FIG. 2 is a bottom schematic view of the anchor shown in FIG.

  The spread anchor 10 includes an anchor tube 12 and an anchor core 14 that is inserted into the anchor tube 12.

The anchor tube 12 has a cylindrical shape in which the upper cylindrical body 20 and the lower cylindrical body 22 are integrated.
The upper cylindrical body 20 and the lower cylindrical body 22 are hollow right circular cylinders having substantially the same diameter.
The anchor core 14 has a conical cone portion 100 whose diameter gradually increases as it reaches a region protruding from a region inserted into the anchor tube 12.

The anchor tube 12 includes a head portion 30 that expands in a direction intersecting the axial direction at an end portion into which the anchor core 14 is inserted.
The head portion 30 is divided by a slit portion 70 formed in the axial direction of the anchor tube 12 so as to be divided and widened (a first hole portion 32, a second hole portion). 34, a third drilling portion 36, and a fourth drilling portion 38.

In this embodiment, the slit portion 70 is formed with four slit portions, and four drilling portions are formed with the slit portion 70 interposed therebetween.
The slit part 70 includes a first slit part 72, a second slit part 74, a third slit part 76, and a fourth slit part 78.
The first hole portion 32 and the second hole portion 34 are adjacent to each other with the first slit portion 72 interposed therebetween, and the second hole portion 34 and the third hole portion 36 are sandwiched between the second slit portion 74. Are adjacent to each other, sandwiching the third slit portion 76, the third drilling portion 36 and the fourth drilling portion 38 are adjacent, and sandwiching the fourth slit portion 78, the fourth drilling portion 38 and the first cutting portion are sandwiched. The hole 32 is adjacent.

The upper cylindrical body 20 of the anchor tube 12 has a screw 28 engraved on the hole wall in the through hole 24.
The lower cylindrical body 22 constitutes the head portion 30 and is formed with the slit portion 70.

The tip on the slit part 70 side of one hole forming part (first hole forming part 32) constituting the hole forming part is formed sharply,
The tip on the slit side of two adjacent drilling portions (second drilling portion 34) across the one drilling portion (first drilling portion 32) is notched,
The tip of the one hole part (first hole part 32) on the slit part 70 side is exposed toward the direction of rotation of the anchor tube 12 during cutting so as to cut the workpiece (C). Is formed.

The tip of the first hole portion 32 constituting the hole portion on the first slit portion 72 side is formed to be sharp.
The front end on the first slit portion 72 side of the second drilled portion 34 adjacent to the first drilled portion 32 across the edge 50 on the first slit portion 72 side is notched.
The tip of the first hole portion 32 on the first slit portion 72 side is formed so as to be exposed in the direction of rotating the anchor tube 12 during cutting and to cut the workpiece (C).

In the first drilled portion 32, a sharpened portion 44 is formed in a region where the end edge 40 and the lower end edge 42 on the first slit portion 72 side intersect or are orthogonal to each other.
The second hole 34 adjacent to each other across the first slit 72 has an edge 50 on the first slit 72 side so as to expose the outer region of the sharpened portion 44 of the first hole 32. A front end region intersecting with the lower end edge 52 is notched on the outer surface, and a notch front end portion 54 is formed which becomes lower toward the first slit portion 72 side.
The sharpened portion 44 has a substantially triangular shape when viewed from the slit portion 70 side, and the rotation direction when cutting the anchor tube 12 so as to cut the periphery of the lower portion of the preceding hole (Ch) of the work piece (C). It stands sharply toward.

The first drilled portion 32 has a notch tip 54 formed on the fourth slit portion 78 side and a sharpened portion 44 formed on the first slit portion 72 side.
The second drilling portion 34 has a notch tip portion 54 formed on the first slit portion 72 side and a sharpened portion 44 formed on the second slit portion 74 side.
The third drilling portion 36 has a notch tip 54 formed on the second slit portion 74 side and a sharpened portion 44 formed on the third slit portion 76 side.
The fourth drilled portion 38 has a notch tip 54 formed on the third slit portion 76 side and a sharpened portion 44 formed on the fourth slit portion 78 side.

The first drilled portion 32 formed with the sharpened portion 44 on the first slit portion 72 side constitutes one drilled portion, and the second drilled portion formed with the notch tip portion 54 on the first slit portion 72 side. The hole 34 constitutes a second drilling part.
The second drilling portion 34 formed with the sharpened portion 44 on the second slit portion 74 side constitutes a single drilling portion, and the third drilled portion 54 formed with the notch tip portion 54 on the second slit portion 74 side. The hole 36 constitutes a second drilling part.
The third drilled portion 36 formed with the sharpened portion 44 on the third slit portion 76 side constitutes one drilled portion, and the fourth drilled portion formed with the notch tip 54 on the third slit portion 76 side. The hole 38 constitutes a second drilling part.
The fourth hole portion 38 formed with the sharpened portion 44 on the fourth slit portion 78 side constitutes one hole portion, and the first hole formed with the notch tip portion 54 on the fourth slit portion 78 side. The hole portion 32 constitutes a second drilling portion.

The anchor tube 12 is driven in the axial direction of the anchor core 14 and is drilled in a region separated along the outer peripheral surface of the anchor core 14 (first drilling portion 32, second drilling portion 34, first The third drilling portion 36 and the fourth drilling portion 38) are expanded and formed to bite into the work piece (C).
The head portion 30 of the anchor tube 12 is formed so as to slide and expand on the surface of the cone portion 100 of the anchor core 14.

The slit portion 70 is formed so that the shavings produced when being cut are guided along the slit portion 70 in the direction opposite to the driving direction.
The anchor tube 12 is driven into the surface of the upper cylindrical body 20 (body part) opposite to the side on which the anchor core 14 is inserted, by cutting powder generated when the workpiece (C) is cut. A shaving powder guide groove 80 is formed to guide the direction opposite to the direction.

The anchor core 14 is a columnar body in which the upper column body 110 and the lower column body 112 are integrated.
The upper column 110 is a right circular cylinder having substantially the same diameter as the through hole 24 of the lower cylinder 22 of the anchor tube 12.
The lower column body 112 is a conical body constituting the cone portion 100 of the conical body.

Next, the usage method of the expansion anchor 10 concerning this invention is demonstrated.
First, a preceding hole (Ch) is drilled at a position where an anchor of a work piece (C) such as a concrete structure is installed with a drill for concrete.
Next, the expansion anchor 10 is set by being inserted into the preceding hole (Ch).
On the other hand, a hexagonal bolt 200 having a male threaded rod 204 protruding from a hexagonal columnar head 202 is prepared. Further, a hexagon nut 206 is screwed into the male screw rod 204 of the hexagon bolt 200.
The outer shape of the head 202 of the hexagon bolt 200 and the hexagon nut 206 is substantially the same.

The male screw rod 204 of the hexagon bolt 200 is screwed into the through hole 24 of the anchor tube 12 of the expansion anchor 10 set in the preceding hole (Ch).
On the other hand, a socket bit 250 having a hole 252 that fits into the head 202 of the hex bolt 200 and the hex nut 206 is prepared, and the hole 252 of the socket bit 250 is covered with the head 202 and the hex nut 206 of the hex bolt 200. Crown.
Furthermore, a rotary driving instrument 280 such as a drill that can be driven while rotating the expansion anchor 10 is prepared.
The socket bit 250 is loaded into the chuck of the rotary driving tool 280 so that the socket bit 250 can be rotated and driven by the rotary driving tool 280.
Then, the rotary driving tool 280 is operated so that the hexagon bolt 200 can be driven while rotating through the socket bit 250.
Thus, the expansion anchor 10 is operated by the rotary driving tool 280, and the workpiece (C) while the anchor tube 12 cuts the workpiece (C) by the rotation and driving of the socket bit 250 and the hexagon bolt 200. ) And slides along the outer peripheral surface of the anchor core 14, and drills holes (the first hole 32, the second hole 34, the third hole 36, and the fourth hole) of the head 30. The drilling portion 38) is expanded and bites into the work piece (C).
Since the sharpened portion 44 of the first drilled portion 32 can be cut by directly contacting the work piece (C), the work piece (C) can be cut reliably and efficiently.

  The cutting powder of the workpiece (C) cut out by the anchor tube 12 of the expansion anchor 10 passes through the slit portion 70, is guided to the cutting powder guide groove 80, gradually rises upward, and expands. It is discharged out of the anchor tube 12 of the open anchor 10.

  When removing the hexagon bolt 200 from the expansion anchor 10 fixed to the workpiece (C), the hexagonal nut 206 is grasped with a spanner or the like, and the head 202 is rotated with the spanner that grasps the head 202. Remove. Since the hexagonal bolt 200 is screwed with the hexagonal nut 206, the hexagonal bolt 200 can be removed from the expansion anchor 10 relatively easily as a reverse screw.

Further, when the expanded anchor 10 is driven into the work (C), the tool 192 is fitted into the stepped portion 26 provided at the entrance of the through hole 24 of the anchor tube 12, and the anchor tube is driven with a driving tool 190 such as a hammer. You can hit 12 and drive in.
The anchor tube 12 slides down on the surface of the cone part 100 of the anchor core 14, and the first drilling part 32 expands along the shape of the cone part 100.
The drilling portion 32 of the anchor tube 12 surely bites into the work piece (C).

The present invention is not limited to the above embodiment, and can be changed based on the idea of the present invention.
Next, an anchor that is a modification of the expansion anchor 10 of the above embodiment will be described.
The anchor of the modification shown in FIG. 14 is mainly different in the configuration of the anchor core 14 from the anchor core 14 of the spread anchor 10 of the above embodiment.
This deformation-side anchor core 14 has a protrusion 104 projecting from the lower end opposite to the region fitted into the anchor tube 12.
The protrusion 104 includes a substantially hexagonal columnar portion when viewed from the bottom.
The protrusion 104 may be formed by a bolt screwed into a female screw hole 106 drilled in the lower end of the anchor core 104, or may be formed integrally with the anchor core 14.
Further, the anchor of the modification shown in FIG. 17 is notched until the notch tip 54 reaches the through hole 24 side. Since the cut-out portion is large, the sharpened portion 44 having a substantially triangular shape as viewed from the slit portion 70 side is more exposed, and the workpiece (C) can be easily cut.

  For example, when fixing an adherend 400 such as a building material such as a base or a pillar to the expansion anchor 10, a bolt 406 is anchored to a through-hole 402 formed in the adherend 400 via a washer 404. Screw onto the screw 28 of the tube 12.

  The base material to which the anchor is applied is not limited to a concrete frame, but also includes a brick frame, a frame made of ALC, resin, or the like.

DESCRIPTION OF SYMBOLS 10 Expanding anchor 12 Anchor tube 14 Anchor core 20 Upper cylinder 22 Lower cylinder 24 Through-hole 26 Step part 28 Screw 30 Head part 32 1st hole part 34 2nd hole part 36 3rd hole part 38 4th Drilling hole 40 First slit side edge 42 (first drilling part) Lower edge 44 (first drilling part) Lower edge 44 Sharpened part 50 (second drilling part) First slit side edge 52 Lower end edge (of second drilled portion) 54 Notch tip portion 70 Slit portion 72 First slit portion 74 Second slit portion 76 Third slit portion 78 Fourth slit portion 80 Shaving powder guide groove 100 Cone portion 104 Protrusion 106 Female thread Part 110 Upper column body 112 Lower column body 190 Driving tool 192 Tool 200 Hexagon bolt 202 Head 204 Male thread rod 206 Hexagon nut 250 Socket bit 252 Hole 280 Rotation Chikomi instrument 400 adherend 402 through hole 404 washer 406 volts C Work object Ch preceding hole

The present invention according to claim 1 is provided with an anchor tube, an anchor core inserted into the anchor tube, and an anchor tube, and a direction intersecting the axial direction of the anchor tube at the end where the anchor core is inserted. A plurality of head portions that are provided in the head portion and that are divided in the axial direction of the anchor tube and that are divided by the slit portions and that are formed on the head portion so as to expand the head portion. The drilling part is formed on the surface of the body part of the anchor tube that is opposite to the side where the anchor core is inserted, and the swarf generated when the work piece is cut is placed on the side opposite to the driving direction. It includes a cutting powder guide groove to be guided, and a protrusion projecting from the lower end of the anchor core opposite to the region fitted in the anchor tube, and the drilled portion is sharpened toward the slit portion side. And a sharpened portion of one of the drilling portions, including two drilling portions adjacent to the one drilling portion across the slit portion and having a notch tip portion on the slit portion side. Is formed so as to cut the workpiece by exposing the anchor tube in the direction of rotation during cutting, and the anchor tube is driven in the axial direction of the anchor core along the outer peripheral surface of the anchor core. This is an expanded anchor that is formed so that the hole portion is expanded and bites into the work.
According to the first aspect of the present invention, since the above-described configuration is provided, the work can be efficiently and efficiently drilled without clogging with the cutting powder, and the work can be reliably made. An expanded anchor can be provided that is secured.
The present invention according to claim 2 is an invention dependent on the invention according to claim 1, wherein the sharpened portion of the one drilling portion is formed between the edge on the slit portion side and the lower end edge of the one drilling portion. The end on the slit portion side of the second drilling portion is formed in an intersecting or orthogonal region, and the notch tip portion of the second drilling portion exposes the outer region in the sharpened portion of the first drilling portion. The expanding anchor is formed such that the front end portion where the edge and the lower end edge intersect with each other is formed such that the outer surface is notched and becomes lower toward the slit portion side.
According to the second aspect of the present invention, since the above-described configuration is provided, the work can be efficiently drilled by the expansion anchor.
The present invention according to claim 3 is an invention dependent on the invention according to claim 1 or claim 2, wherein the anchor tube has a cylindrical shape in which the upper cylindrical body and the lower cylindrical body are integrated, and the upper cylinder. The body is a spread anchor in which a screw is engraved on the hole wall in the through-hole, and the lower cylindrical body is formed with a head portion having a hole portion and a slit portion.
According to the third aspect of the present invention, since the above-described configuration is provided, it is possible to efficiently drive the expansion anchor.
The present invention according to claim 4 is an invention dependent on the invention according to any one of claims 1 to 3, wherein the anchor core reaches a region protruding from a region inserted into the anchor tube. Accordingly, the head portion of the anchor tube is an expanding anchor formed so as to slide and expand on the surface of the cone portion of the anchor core.
According to the fourth aspect of the present invention, since the above-described configuration is provided, the expansion anchor is securely fixed to the work piece.

ADVANTAGE OF THE INVENTION According to this invention, while being able to drill a work efficiently and efficiently, without clogging with cutting powder, the expansion anchor fixed firmly to a work can be provided.

Claims (5)

An anchor tube, and an anchor core fitted into the anchor tube,
The anchor tube includes a head portion that expands in a direction crossing the axial direction at an end portion into which the anchor core is fitted,
The head portion has a plurality of drilling portions formed so as to be divided and expanded by a slit portion drilled in the axial direction of the anchor tube,
The tip on the slit side of one of the drilling portions constituting the drilling portion is formed sharply,
The tip on the slit side of the two drilling portions adjacent to each other with the slit portion sandwiched between the one drilling portion is cut out,
The tip on the slit side of the one hole portion is exposed toward the direction of rotating the anchor tube at the time of cutting, and is formed so as to cut the workpiece.
The slit is formed such that the shavings produced when being cut are guided in a direction opposite to the driving direction along the slit,
The anchor tube is driven so as to be driven in the axial direction of the anchor core, the drilling portion is expanded along the outer peripheral surface of the anchor core, and is formed so as to bite into the work piece.
Expanding anchor. The one drilling portion has a sharpened portion formed in a region where the edge on the slit side and the lower end edge intersect or are orthogonal to each other,
The two drilling portions adjacent to each other across the slit have an outer end portion where the edge on the slit side intersects with the lower end edge so that the outer region of the sharpened portion of the first drilling portion is exposed. The expansion anchor according to claim 1, wherein a notch tip portion is formed, the side surface of which is notched and becomes lower toward the first slit side.   The anchor tube guides the cutting powder produced when the work piece is cut on the surface of the body part opposite to the side where the anchor core is inserted, to the opposite side to the driving direction. The expansion anchor according to claim 1, wherein a groove is formed. The anchor core has a conical cone portion whose diameter gradually increases as it reaches a region protruding from the region inserted into the anchor tube,
The expansion anchor according to any one of claims 1 to 3, wherein the head portion of the anchor tube is formed to slide and expand on the surface of the cone portion of the anchor core. The anchor tube has a cylindrical shape in which the upper cylindrical body and the lower cylindrical body are integrated.
The upper cylinder is engraved with a screw on the hole wall in the through hole,
The expansion anchor according to any one of claims 1 to 4, wherein the lower cylindrical body is formed with a head portion having a drilling portion and a slit portion.