JP2022144351A - Post-installation anchor and installation method thereof - Google Patents

Abstract

To provide a post-installation anchor and an installation method thereof allowing an installation state of an anchor to be stabilized even in a state without attachment of attachment objects, flexibility of installation work to be enhanced, and workability to be improved.SOLUTION: A post-installation anchor 1 is provided with: a head 2 which has a male screw part 21 formed on a base end side and a cylindrical column part 23 in a generally cylindrical column shape formed on a tip side though a taper part 22 whose diameter gradually expands toward the tip and which includes an uneven shape on at least a part of an outer peripheral surface 231 of the cylindrical column part 23; an expansion sleeve 3 which has a plurality of expansion blades 32 arranged in circumferential direction with slits 31 cut from the tip to expand the expansion blades 32 such that the expansion blades 32 run on the taper part 22 toward a tip of the head 2; and a female screw body 4 which has a female screw part 41 threadably engageable with the male screw part 21 from the tip toward the base end side to hold an expansion state of the expansion blades 32 of the expansion sleeve 3 of the tip side through thread engagement between the female screw part 41 and the male screw part 21.SELECTED DRAWING: Figure 1

Description

The present invention relates to a so-called undercut type post-installed anchor, for example, in which a hole is formed in concrete by enlarging the diameter of a portion near the bottom of the hole, and the tip of the anchor is widened at the expanded bottom of the hole, and a method for installing the same. .

Conventionally, an undercut type post-construction is performed in which a hole is formed in the concrete by expanding the diameter near the bottom of the hole, and the tip of the anchor is expanded at the expanded bottom of the hole and installed in the concrete. Anchors are known. The undercut anchor does not obtain fixing force by friction fixation by pressing the expansion piece of the sleeve against the wall of the concrete drilled hole, but rather opens the expansion blades of the sleeve along the expanded bottom of the pre-formed hole. Since the expanding blades are fixed on the expanding bottom part, it is possible to reliably exhibit high fixing power even in high-strength concrete where metal cannot bite into concrete.

As such an undercut type anchor, there is an anchor disclosed in Patent Document 1. This anchor has a shaft with an enlarged diameter portion at the tip and a bolt portion at the other end. The outer peripheral surface of the enlarged diameter portion is tapered. By driving the sleeve into the enlarged diameter portion side of the shaft body, the expansion blades of the sleeve are expanded along the enlarged bottom portion of the bore.

JP 2016-132901 A

By the way, as in Patent Document 1, the shaft body 111 has an enlarged diameter portion 112 with a tapered outer peripheral surface at the tip, a bolt portion 113 is formed at the other end, and a spreading blade 115 is formed at the tip. When installing the anchor 110 composed of the sleeve 114 on the concrete 120, immediately after the anchor 110 is driven, the attachment 130 is externally placed on the bolt portion 113, and the nut for tightening the nut 140 on the bolt portion 113 from the outside. Once tightened, the expanding wings 115 of the sleeve 114 cannot move from the expanded bottom portion 122 of the bore 121, so that the anchor 110 is stably fixed to the concrete 120 (see FIG. 11(a)).

However, if a certain amount of time elapses between driving the anchor 110 and attaching the attachment 130, springback occurs in the spreading wings 115 of the sleeve 114, causing the sleeve 114 to come out gradually ( See FIGS. 11(b) and (c)). That is, in the construction process of this type of anchor, since no time can be left between driving the anchor and attaching the attachment, there is a problem that the degree of freedom in the construction work is low and the workability is poor.

The present invention is proposed in view of the above problems, and can stabilize the installation state of the anchor even in a state where no attachment is attached, increase the degree of freedom in construction work, and improve workability. It is an object of the present invention to provide a post-installed anchor and its installation method.

In the post-installed anchor of the present invention, a male threaded portion is formed on the base end side, and a substantially cylindrical cylindrical portion is formed on the distal end side via a tapered portion that gradually expands in diameter toward the distal end, and the outer peripheral surface of the cylindrical portion. and a plurality of expanding blades are provided in the circumferential direction by slits cut from the tip of the head, and the expanding blades extend toward the tapered portion toward the tip of the head. An expansion sleeve on which the expansion blades are expanded by riding on the expansion sleeve, and a female threaded portion that can be screwed into the male threaded portion from the distal end toward the base end are formed. and a female screw body for holding the expanded state of the expansion blades of the expansion sleeve on the distal end side.
According to this, while preventing co-rotation of the head by hooking the uneven shape on the hole wall of the bore, the female threaded portion of the female threaded body is screwed into the male threaded portion of the head and screwed into the expansion sleeve. The spread state of the spread blades can be maintained and stabilized. In other words, even when no attachment is attached, after the female threaded part of the female threaded body is screwed into the male threaded part of the head, when a force acts on the post-installed anchor in the pull-out direction, the head will further open the expansion blades. As a result, the installation state of the construction anchor can be stabilized. Therefore, it is possible to perform a construction process in which a certain amount of time elapses from the installation of the post-installed anchors before the installation of the attached object, and the like, so that the degree of freedom in the construction work can be increased and the workability can be improved.

In the post-installed anchor of the present invention, the expansion sleeve and the female threaded body are separate bodies, and the expansion blades are expanded by contacting the distal end surface of the female threaded body with the proximal end surface of the expansion sleeve. is characterized by holding
According to this, by making the expansion sleeve and the female threaded body separate, when the female threaded body is rotated and screwed into the head, the base end surface of the expansion sleeve, which is separate from the female threaded body, As the head is screwed into the female threaded body, it is pushed by the distal end surface of the female threaded body, and the expansion blades of the expansion sleeve are opened through the slits. At this time, the base end face of the expansion sleeve is in stable contact with the tip end face of the female screw body, and the two are separate bodies. The expansion blades can ride on the tapered portion of the head and expand smoothly without being hindered by the rigidity of the head. In addition, even if the expansion sleeve and the female threaded body are separated, the expansion sleeve rides on the tapered part at the position sandwiched between the female threaded body and the tip of the head screwed into it, so that it expands. , the expansion sleeve cannot be retracted toward the opening due to the springback of the expansion sleeve, and the stability of the expanded state of the expansion blades of the expansion sleeve is not hindered.

In the post-installed anchor of the present invention, the female threaded body has a substantially cylindrical shape, and another female threaded portion that can be screwed into the mounting bolt from the base end to the distal end side is formed coaxially with the female threaded portion. characterized by
According to this, by making the female threaded body substantially cylindrical in which another female threaded portion is formed from the proximal end to the distal end side, the post-installed anchor protrudes from the installation surface such as the concrete wall surface in the state where the post-installed anchor is installed. Protrusions such as bolts are eliminated to prevent the protrusions from interfering with other construction work. In addition, depending on the thickness of the object to be attached, a mounting bolt of any length can be screwed into a different internal thread to be used, making it possible to handle various thicknesses of the object to be attached, resulting in versatility. Excellent for

The post-installed anchor of the present invention is characterized in that an outwardly protruding anti-rotation protrusion is provided on the outer peripheral surface of the cylindrical portion of the head so as to be able to press against the hole wall of the bore.
According to this, the co-rotation of the head can be more reliably prevented by the pressure contact of the anti-rotation projection against the hole wall of the drilled hole, and the female threaded portion of the female threaded body can be more reliably screwed into the male threaded portion of the head. .

The post-installed anchor of the present invention is characterized in that the outer peripheral surface of the tapered portion of the head is formed as an R surface that is recessed inward in an arc shape. More preferably, the inner surface of the tip portion of the expanding blade is configured to be an inclined surface that is inclined so as to widen toward the tip side.
According to this, it is possible to prevent the expansion blades of the expansion sleeve from being caught on the outer peripheral surface of the tapered portion, and to smoothly expand the expansion blades so as to follow the arcuate recessed R surface. Furthermore, if the inner surface of the tip of the expansion blade is configured to be an inclined surface that widens toward the tip side, the expansion blade can be moved so as to follow the arc-shaped recessed R surface. , the expansion blades can be expanded more smoothly.

The post-installed anchor construction method of the present invention is a method of installing the post-installed anchor of the present invention, wherein a hole is formed in concrete so as to form an enlarged bottom portion having an enlarged diameter near the bottom of the hole. 1 step, in which the expansion sleeve and the female threaded body are sequentially inserted onto the male threaded portion of the head, and the vicinity of the tip of the female threaded portion of the female threaded body is screwed to the male threaded portion; a second step of inserting the anchor into the bore and driving the post-installed anchor until the tip of the head reaches the bottom of the bore; It is characterized by comprising a third step of moving the expansion sleeve to the bottom side, causing the expansion blades of the expansion sleeve to ride on the tapered portion, and expanding the expansion blades at the expansion bottom portion.
According to this method, a post-installed anchor composed of a head, an expansion sleeve, and a female threaded body is inserted into a hole, and from this state, the female threaded body that has already been screwed to the male threaded portion is screwed into the hole, and an impact wrench or the like is inserted. It is possible to expand the expansion blades by mechanical construction using an electric rotary tool with good workability. In addition, it is possible to reduce the work that requires high precision such as aligning the female threaded portion of the female threaded body with the male threaded portion of the head in the drilled hole, hooking it, and screwing it together, thereby improving workability. .

The post-installed anchor construction method of the present invention is a method of installing the post-installed anchor of the present invention, wherein a hole is formed in concrete so as to form an enlarged bottom portion having an enlarged diameter near the bottom of the hole. Step 1: inserting the head and the expansion sleeve into the bore with the expansion sleeve separate from the male thread body being fitted over the male threaded portion of the head, and inserting the expansion sleeve into the hole; a second step of driving the expansion blade with a driving rod to expand the expanding blade at the expanded bottom portion; inserting the female threaded body into the bore; a third step of inserting and bringing the distal end surface of the female screw body into contact with the base end surface of the expansion sleeve to maintain the expanded state of the expansion blades.
According to this, it is possible to carry out the work manually using a widely used hammering rod without using an electric tool for expanding the post-installed anchor, so that the work can be carried out in a wider variety of construction environments. It becomes possible to

According to the present invention, the installation state of the post-installed anchor can be stabilized even in a state in which no attachment is attached, the flexibility of the post-installed anchor construction work can be increased, and the workability can be improved.

(a) is a front view of a post-installed anchor according to an embodiment of the present invention, (b) is a view along line AA in (a), and (c) is a longitudinal section of the post-installed anchor in FIG. figure. (a) is a left side view of the female threaded body in the post-installed anchor of the embodiment, (b) is a front view of the female threaded body of FIG. Figure, (d) is a front view of the head in the post-installed anchor of the embodiment, (e) is a right side view of the head of the figure (d). FIG. 4 is a perspective explanatory view of a head, an expansion sleeve, an internal thread body, and a jig for setting the post-installed anchor in the post-installed anchor of the embodiment; (a) to (d) are process explanatory diagrams of the first half process in the first example of the method of constructing the post-installed anchor according to the embodiment. (a) to (e) are process explanatory diagrams of the latter half process in the first example of the method of constructing the post-installed anchor according to the embodiment. (a) is a partial cross-sectional explanatory view of a state in which an attachment is attached with a post-construction anchor of the embodiment, and (b) is a cross-sectional explanatory view thereof. (a) to (c) are process explanatory diagrams of the first half process in the second example of the method of constructing the post-installed anchor according to the embodiment. (a) to (d) are process explanatory diagrams of the second half of the process in the second example of the method of constructing the post-installed anchor according to the embodiment. (a) is a front view of a modified head, and (b) is a right side view thereof. (a) is a front view of a state in which the internal thread body is separated by the construction anchor after the modification, and (b) is a vertical cross-sectional view thereof. (a) is a fracture explanatory diagram of a state in which a post-installed anchor is driven into concrete in a conventional example and an attached object is attached, (b) is a fracture explanatory diagram of a state in which a post-installed anchor is driven into concrete in a conventional example, (c) Fig. 10 is a broken explanatory view of a state in which the sleeve has come out due to springback from the state of Fig. 1(b);

[Anchor installed after embodiment]
As shown in FIGS. 1 to 3, the post-installed anchor 1 according to the embodiment of the present invention has a male threaded portion 21 formed on the proximal end side, and a tapered portion 22 gradually increasing in diameter toward the distal end side. A head 2 having a substantially cylindrical columnar portion 23 formed thereon, and an expansion sleeve 3 externally inserted over a portion of the head 2 on the proximal side from the tapered portion 22 in the non-expanded state, which is the male screw portion 21 in the illustrated example. , a female threaded body 4 formed with a female threaded portion 41 that can be screwed into the male threaded portion 21 of the head 2 from the distal end toward the base end.

The head 2 is formed so that the outer peripheral surface 221 of the tapered portion 22 is a rounded surface that is slightly recessed inward in an arc shape, and is a curved surface that is slightly curved inward. At least part of the outer peripheral surface 231 of the cylindrical portion 23 of the head 2 is provided with an uneven shape. A plurality of anti-rotation grooves 232 are formed by opening, in the illustrated example, four anti-rotation grooves 232 are formed at equal intervals in the circumferential direction. The anti-rotation groove 232 in the illustrated example is cut so as to be inclined inward toward the distal end of the head 2 .

Anti-rotation blades 233 and 233 are respectively fitted in the anti-rotation grooves 232 and 232 at the two opposing locations among the four anti-rotation grooves 232 , and the anti-rotation blades 233 and 233 are attached to the cylindrical portion 23 of the head 2 . is provided so as to protrude outward from the outer peripheral surface 231 of the . The detent blade 233 in the illustrated example has a substantially triangular plate shape, and is formed substantially following the shape and width of the detent groove 232 cut into a substantially triangular shape. The detent blades 233, 233 of this embodiment correspond to detent projections projecting outward from the outer peripheral surface 231 of the cylindrical portion 23 of the head 2, and are provided so as to be able to press against the wall of a hole formed in concrete or the like. It is

The expansion sleeve 3 has a substantially cylindrical shape, and has a plurality of expansion blades 32 in the circumferential direction by slits 31 cut from the tip thereof. In the expansion sleeve 3 of this embodiment, an annular groove 34 is formed in the circumferential direction on the distal end side of the base end annular portion 33, and the portion where the annular groove 34 is formed is a thin portion. A spreading blade 32 is provided on the tip side of this thin portion, and the spreading blade 32 is formed on the tip side of the base end ring portion 33 via the thin portion. Each slit 31 that partitions the expansion blade 32 extends from the tip to the annular groove 34 and is formed to reach the tip surface of the base end ring portion 33 . In addition, the inner surface of the tip portion of each expansion blade 32 is an inclined surface 321 that is inclined so as to widen toward the tip side. An inclined surface 321 is formed by chamfering the inner diameter so as to increase the inner diameter.

When the expanding sleeve 3 is pushed out or driven toward the distal end of the head 2 from a state of being externally inserted on the proximal end side of the tapered portion 22 of the head 2 , the expansion sleeve 3 expands toward the distal end of the head 2 . The blade 32 rides on the tapered portion 22, and the expansion blade 32 is expanded by the riding on the tapered portion 22 to be in the expanded state. At this time, the outer peripheral surface 221 of the tapered portion 22 of the head 2 , which is curved inwardly, and the inclined surface 321 at the tip of the expanding blade 32 , allow the expanding blade 32 to move very smoothly to the outer peripheral surface 221 . It can be moved along and expanded.

The female threaded body 4 is separate from the expansion sleeve 3 in this embodiment, and is generally formed in a substantially cylindrical shape over its entirety, which is cylindrical in the illustrated example. The female threaded body 4 is formed with a female threaded portion 41 that can be screwed into the male threaded portion 21 of the head 2 from the distal end to the proximal side, and can be screwed into the mounting bolt from the proximal end to the distal side. Another female threaded portion 42 is formed coaxially with the female threaded portion 41 . Between the base end of the female threaded portion 41 and the distal end of another female threaded portion 42 in the female threaded body 4 is a reduced diameter portion 43 without a thread groove, and the reduced diameter portion 43 can regulate the screwing amount of the mounting bolt. It has become.

The female threaded body 4 can hold the expanded state of the expansion blades 32 of the expansion sleeve 3 on the distal end side by screwing the female threaded portion 41 and the male threaded portion 21 of the head 2. The tip surface of the body 41 abuts the base end surface of the expansion sleeve 3, so that the expanded state of the expansion blades 32 can be maintained (see FIGS. 5(d) and 5(e)). Engagement grooves 44 for engaging and attaching a driving jig are formed at two locations in the circumferential direction of the base end portion of the female screw body 4 .

Next, the 1st example of the construction method of the post-installation anchor 1 of this embodiment is demonstrated. In the construction method of the first example, first, after forming a straight hole 63m in the concrete 61 from the wall surface 62 with a drill 71, a dedicated bottom enlarging tool 72 is inserted into the hole 63m to expand the diameter of the portion near the hole bottom 65. , a borehole 63 having an enlarged bottom 64 is formed in the concrete 61 (see FIGS. 4a and 4b).

After that, the expansion sleeve 3 and the female threaded body 4 are sequentially inserted onto the male threaded portion 21 of the head 2, and the post-installed anchor 1 is installed in a state in which the male threaded portion 21 is screwed to the vicinity of the distal end of the female threaded portion 41 of the female threaded body 4. The post-installed anchor 1 is inserted into the hole 63 and driven until the tip of the head 2 reaches the hole bottom 65 of the hole 63 (see FIGS. 4(c), (d) and 5(a)). After the driving is completed, the vicinity of the engagement groove 44 of the female thread body 4 of the post-installed anchor 1 protrudes from the wall surface 62 of the concrete 61 . At this time, by setting the length from the tip of one detent blade 233 of the head 2 to the tip of the opposite detent blade 233 to be slightly larger than the perforation diameter, the detent blades 233 and 233 are perforated. It bites into the hole wall 66 near the hole bottom 65 of the hole 63, and it becomes possible to reliably stop rotation when rotating the female screw body 4 which will be described later.

Then, the engaging ridges 52, 52 extending in the axial direction of the driving jig 51 are engaged with the engaging grooves 44, 44 of the female screw body 4, and an electric rotating tool 54 such as an impact wrench is attached to the driving jig. It is attached to the chuck 53 of the tool 51, and the internal thread body 4 is rotated by the rotating operation of the electric rotating tool 54 (see FIGS. 5(b) and 5(c)). When the female threaded body 4 is rotated, the female threaded part 41 of the female threaded body 4 is screwed into the male threaded part 21 of the head 2 whose co-rotation is prevented, and is screwed into the hole 63 of the female threaded body 41 toward the hole bottom 65 side. With the movement of , the expansion sleeve 3 , whose distal end face of the female threaded body 4 abuts the proximal end face, is also pushed by the female threaded body 4 and moves toward the hole bottom 65 side of the bore 63 . By this movement of the expansion sleeve 3, the expansion blade 32 of the expansion sleeve 3 rides on the tapered portion 22 of the head 2, and the expansion blade 32 divided through the slit 31 expands at the expanded bottom portion 64 of the perforation 63. It is expanded so as to substantially follow the shape of the portion 64 (see FIG. 5(d)).

In this way, when the post-installed anchor 1 is embedded in the concrete 61 and installed, the female threaded portion 41 of the female threaded body 4 and the male threaded portion 21 of the head 2 are integrated by screw connection. The expansion blades 32 of the expansion sleeve 3 whose faces are in contact with the base end face cannot move from the expanded state of the expanded bottom portion 64 . That is, when the female threaded body 4 tries to escape from the hole 63, the head 2 is pulled toward the female threaded body 4, and the expanding blade 32 expands to the outside of the expanded bottom portion 64 and returns to its original non-expanded state. (See thick line arrow in FIG. 5(e)). Therefore, there is no danger of the post-installed anchor 1 slipping out of the hole 63 due to narrowing of the expansion blades 32, and the post-installed anchor 1 is stably fixed to the concrete 61.例文帳に追加

After that, a mounting bolt 81 is screwed into another female threaded portion 42 of the female threaded body 4, and an attachment 82 is arranged so as to be externally inserted into the attachment bolt 81 and along the wall surface 62 of the concrete 61. A nut 84 such as a locking nut is screwed onto the mounting bolt 81 via a washer 83 from the outside of 82, and tightened to mount the mounting object 82 on the concrete 61 (see FIGS. 5(e) and 6).

Next, a second example of the construction method of the post-installed anchor 1 of this embodiment will be described. In the construction method of the second example, first, by the same steps as in the first example, a hole 63 having an expanded bottom portion 64 with an enlarged diameter near the hole bottom 65 is formed in the concrete 61, and the formed hole 63 is The head 2 and the unexpanded expansion sleeve 3 are inserted in a state in which the expansion sleeve 3, which is separate from the male thread body 4, is externally inserted into the male threaded portion 21 of the head 2 (see FIG. 7(a)). .

Further, a driving rod 73 having at least a cylindrically formed tip portion into which the male screw portion 21 of the head 2 can be inserted is brought into contact with the base end surface of the expansion sleeve 3, and the hole bottom 65 side of the hole 63 is struck with a hammer 74 or the like. The expansion sleeve 3 is driven in. When the expansion sleeve 3 is driven in, the tip of the head 2 first reaches the bottom 65 of the hole, and the length from the tip of one anti-rotation vane 233 of the head 2 to the tip of the opposite anti-rotation vane 233 is larger than the hole diameter. By setting the size slightly larger, the anti-rotation vanes 233, 233 can be made to bite into the hole wall 66 near the bottom 65 of the hole, and a structure capable of preventing rotation can be achieved. As the driving of the expansion sleeve 3 is continued, the expansion blades 32 of the expansion sleeve 3 ride up on the tapered portion 22 of the head 2, and the expansion blades 32 approximately conform to the shape of the expanded bottom portion 64 at the expanded bottom portion 64 of the perforation 63. It is expanded so as to follow (see FIGS. 7(b) and (c)).

After recovering the driving rod 73 , the female threaded body 4 is inserted into the bore 63 , and the axially extending engaging ridges 52 of the driving jig 51 are engaged with the engaging grooves 44 of the female threaded body 4 . Then, the female threaded body 4 is rotated in the same manner as in the first example, and the female threaded part 41 of the female threaded body 4 is screwed into the male threaded part 21 of the head 2 so that the distal end surface of the female threaded body 4 is fitted to the proximal end surface of the expansion sleeve 3. 8A to 8C). That is, as in the case of construction in the first example, when the female threaded body 4 attempts to escape from the bore 63, the head 2 is pulled toward the female threaded body 4, and the expansion blade 32 spreads outside the expanded bottom portion 64. It cannot return to the original non-expanded shape (see the thick arrow in FIG. 8(c)). Therefore, there is no danger of the post-installed anchor 1 slipping out of the hole 63 due to narrowing of the expansion blades 32, and the post-installed anchor 1 is stably fixed to the concrete 61.例文帳に追加

After that, as in the first example, the mounting bolt 81 is screwed into another internal thread portion 42 of the internal thread body 4 and screwed, and the mounting object is inserted over the mounting bolt 81 and along the wall surface 62 of the concrete 61 . 82 is placed, and a nut 84 such as a locking nut is screwed onto the mounting bolt 81 via a washer 83 from the outside of the attachment 82, and tightened to attach the attachment 82 to the concrete 61 (FIG. 8(d)). ), see FIG. 6).

According to the post-installed anchor 1 of the present embodiment, for example, the head 2 is prevented from co-rotating by hooking the uneven shape on the hole wall 66 of the hole 63 of the concrete 61, and the female thread body 4 is attached to the male thread portion 21 of the head 2. By screwing the female threaded portion 41 into and screwed on, the expanded state of the expansion blades 32 of the expansion sleeve 3 can be maintained and stabilized. That is, even if the attachment 82 is not attached, after the female threaded portion 41 of the female threaded body 4 has been screwed into the male threaded portion 21 of the head 2, the head 2 will continue to move when a force acts on the post-installed anchor 1 in the pull-out direction. Since the expansion blade 32 is about to be opened, the installation state of the post-construction anchor 1 can be stabilized. Therefore, it is possible to perform a construction process in which the attachment 82 is mounted after a certain amount of time has passed since the installation of the post-installed anchor 1, so that the degree of freedom in the construction work can be increased and the workability can be improved.

In addition, by making the expansion sleeve 3 and the female threaded body 4 separate, when the female threaded body 4 is rotated and screwed into the head 2, the expansion sleeve 3, which is separate from the female threaded body 4, can be disassembled. As the head 2 is screwed into the female threaded body 4 , the base end face is pushed by the distal end face of the female threaded body 4 , and the expansion blades 32 of the expansion sleeve 3 are opened through the slits 31 . At this time, the base end surface of the expansion sleeve 3 is stably brought into close contact with the distal end surface of the female threaded body 4, and since the two are separate bodies, the expansion blades 32 of the expansion sleeve 3 are expanded through the slits 31. The opening deformation is not hindered by the rigidity of the internal thread body 4, and the expansion blade 32 can ride on the tapered portion 221 of the head 2 to smoothly expand. In addition, since the expansion sleeve 3 rides on the tapered portion 221 at a position sandwiched between the female threaded body 4 and the distal end portion of the head 4 screwed into it, the expansion sleeve 3 springs back to the hole. It is not possible to retreat to the mouth side, and the stability of the expanded state of the expansion blades 32 of the expansion sleeve 3 is not hindered.

In addition, by forming the female threaded body 4 into a substantially cylindrical shape in which another female threaded portion 42 is formed from the proximal end to the distal end side, when the post-installed anchor 1 is installed, a bolt or the like protruding from the concrete wall surface 62 can be removed. It is possible to eliminate protrusions and prevent the protrusions from interfering with other construction work. In addition, depending on the thickness of the object 82 to be attached, the mounting bolt 81 of any length can be screwed into another internal thread portion 42 to be used, and various thicknesses of the object 82 to be attached can be accommodated. It is possible and versatile.

In addition, by pressing the anti-rotation vanes 233, 233 corresponding to the anti-rotation protrusions against the hole wall 66 of the perforation 63, co-rotation of the head 2 is more reliably prevented, and the male screw portion 21 of the head 2 is internally threaded. The female screw portion 41 of the body 4 can be screwed in more securely.

In addition, the tapered portion 22 of the head 2 has an arcuately recessed outer peripheral surface 221 and an inclined surface 321 at the tip of the expanding blade 32 . It can be moved so as to follow the surface 221 and spread more smoothly.

Further, according to the construction method of the first example, the post-installed anchor 1 composed of the head 2, the expansion sleeve 3, and the female thread body 4 is inserted into the hole 63 and already screwed to the male thread portion 21 from this state. By screwing in the internal thread body 4 and expanding the expansion blades 32 by mechanical work using an electric rotating tool such as an impact wrench, it is possible to perform the work with good workability. In addition, it is possible to reduce the work that requires high precision such as aligning the female threaded portion 41 of the female threaded body 4 with the male threaded portion 21 of the head 2 in the hole 63 and hooking and screwing the female threaded portion 41 at the time of construction. can be improved. Moreover, according to the construction method of the second example, the widely used driving rod 73 can be used for construction, and construction can be performed in a wider variety of construction environments.

[Scope of invention disclosed in this specification]
In addition to each invention, embodiment, and each example listed as an invention, the invention disclosed in this specification is specified by changing these partial contents to other contents disclosed in this specification within the applicable range or specified by adding other content disclosed in this specification to these contents, or specified by deleting these partial contents to the extent that partial effects can be obtained and making them a broader concept include those that The invention disclosed in this specification also includes the following contents and the following further modifications.

For example, the head 2 of the post-installed anchor 1 in the above embodiment is formed so that the outer peripheral surface 221 of the tapered portion 22 is slightly arcuately recessed inward. Alternatively, the outer peripheral surface 221a of the tapered portion 22a may be formed as a linearly inclined surface. Further, depending on the strength of the concrete and the diameter of the drilled hole, the anti-rotation groove 232 of the head 2, 2a itself may be formed into an uneven shape provided on at least a part of the outer peripheral surface 231 of the cylindrical portion 23, and the corner of the tip of the head due to this uneven shape, that is, Co-rotation may be prevented by hooking the corner of the anti-rotation groove 232 on the hole wall 66 .

In addition, when performing impact type construction as in the construction method of the second example described above, instead of the substantially cylindrical female thread body 4 over the entire length, a bolt type female thread body 4b shown in FIG. 10 is used. It is also possible to configure the construction anchor 1b. The female threaded body 4b has a substantially cylindrical base portion 45b with a predetermined length of female threaded portion 41b that can be screwed into the male threaded portion 21 of the head 2 from the distal end toward the proximal side. A male threaded portion 46b is formed so as to project therefrom. In the post-installed anchor 1b as well, it is possible to maintain the expanded state of the expansion blades 32 of the expansion sleeve 3 on the tip side by screwing the female threaded portion 41b and the male threaded portion 21 of the head 2 together. When constructing the post-installed anchor 1b, for example, it is constructed by rotating the female threaded body 4b and screwing the female threaded portion 41b into the male threaded portion 21 of the head 2 installed in the state shown in FIG. 8(a).

Further, the post-installed anchor of the present invention also includes one in which the expansion sleeve 3 and the female thread body 4 are not separate but integral members.

INDUSTRIAL APPLICABILITY The present invention can be used, for example, as an undercut type post-installed anchor in which a hole is formed in concrete by enlarging the diameter of the portion near the bottom of the hole, and the tip of the anchor is widened at the expanded bottom of the hole. .

DESCRIPTION OF SYMBOLS 1, 1b... Post-installation anchor 2, 2a... Head 21... Male screw part 22, 22a... Tapered part 221, 221a... Outer peripheral surface 23... Cylindrical part 231... Outer peripheral surface 232... Anti-rotation groove 233... Anti-rotation vane 3... Expansion Sleeve 31... Slit 32... Expanding blade 321... Inclined surface 33... Base end ring part 34... Annular groove 4, 4b... Female screw body 41, 41b... Female screw part 42... Another female screw part 43... Diameter reduction part 44... Engagement Groove 45b Base portion 46b Male screw portion 51 Placement jig 52 Engagement ridge 53 Chuck 54 Electric rotating tool 61 Concrete 62 Wall surface 63, 63m Drill hole 64 Expanded bottom portion 65 Hole bottom 66 Hole wall 71 Drill 72 Enlarged bottom tool 73 Hammer 81 Mounting bolt 82 Attachment 83 Washer 84 Nut 110 Anchor 111 Shaft 112 Expanded diameter portion 113 Bolt portion 114 Sleeve DESCRIPTION OF SYMBOLS 115... Expansion blade|wing 120... Concrete 121... Perforation 122... Expansion bottom part 130... Attachment 140... Nut

Claims (7)

A male threaded portion is formed on the base end side, and a substantially cylindrical cylindrical portion is formed on the distal end side via a tapered portion that gradually expands in diameter toward the distal end. a head provided;
An expansion sleeve in which a plurality of expansion blades are provided in the circumferential direction by slits cut from the tip, and the expansion blades are expanded by riding on the tapered portion toward the tip of the head. When,
A female threaded portion that can be screwed into the male threaded portion is formed from the distal end toward the base end, and the threaded engagement between the female threaded portion and the male threaded portion controls the expanded state of the expansion blades of the expansion sleeve on the distal end side. A post-installed anchor comprising a retaining internal thread body. The expanding sleeve and the female threaded body are separate bodies,
2. The post-installed anchor according to claim 1, wherein the expanded state of the expansion blades is maintained by the distal end surface of the female screw body coming into contact with the proximal end surface of the expansion sleeve. 2. The female threaded body is substantially cylindrical, and another female threaded portion is formed coaxially with the female threaded portion that can be screwed onto the mounting bolt from the proximal end toward the distal end. 2 Installation anchor after the description. 4. The rear end according to any one of claims 1 to 3, wherein an outwardly protruding anti-rotation protrusion is provided on the outer peripheral surface of the cylindrical portion of the head so as to be press-contactable with the hole wall of the bore. construction anchor. The post-installed anchor according to any one of claims 1 to 4, wherein the outer peripheral surface of the tapered portion of the head is formed as an R surface recessed inward in an arc shape. A method for constructing a post-installed anchor according to any one of claims 1 to 5,
a first step of forming a hole in the concrete by forming an enlarged bottom portion having an enlarged diameter at a portion near the bottom of the hole;
The expansion sleeve and the female threaded body are sequentially inserted onto the male threaded portion of the head, and the post-installed anchor is drilled in a state in which the vicinity of the distal end of the female threaded portion of the female threaded body is screwed into the male threaded portion. a second step of driving the post-installed anchor until the tip of the head reaches the bottom of the hole;
The female threaded body is screwed into the expansion sleeve to move the expansion sleeve toward the hole bottom side of the hole, and the expansion blade of the expansion sleeve rides on the tapered portion to expand the expansion blade at the expansion bottom portion. A method of constructing a post-installed anchor, characterized by comprising a third step of opening. A method for constructing a post-installed anchor according to any one of claims 1 to 5,
a first step of forming a hole in the concrete by forming an enlarged bottom portion having an enlarged diameter at a portion near the bottom of the hole;
In a state in which the expansion sleeve separate from the male screw body is fitted around the male threaded portion of the head, the head and the expansion sleeve are inserted into the bore, and the expansion sleeve is pushed by a driving rod. a second step of driving the expanding blades to expand the expanding blades at the expanding bottom portion;
The female threaded body is inserted into the bore, the female threaded section of the female threaded body is screwed into the male threaded section of the head, and the distal end surface of the female threaded body is brought into contact with the proximal end surface of the expansion sleeve, thereby expanding the expansion sleeve. A method of constructing a post-installed anchor, characterized by comprising a third step of maintaining the expanded state of the open blades.

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