Anchor

Abstract

To provide an anchor that can be fixed in a specific position and can be used repeatedly.SOLUTION: An anchor comprises: an anchor insertion hole expanded diameter portion 8 provided at a tip side of an anchor insertion hole 3 and larger than an inner peripheral surface 7N of the anchor insertion hole 3; a step surface 15 provided between the inner peripheral surface 7N and the anchor insertion hole expanded diameter portion 8; a main body 4 cut at a tip to have a longitudinal slit 21 to be divided and provided with an expanded portion 22 that can be inserted into and removed from the anchor insertion hole 3; a core rod insertion hole 5 provided in the main body 4; a core rod 6 inserted into the core rod insertion hole 5 from a base end side; and a step surface 24D provided in the expanded portion 22 having a spring property that expands in diameter when the core rod 6 is inserted into the core rod insertion hole 5 and engaging with the step surface 15 when the expanded portion 22 expands in diameter. When the core rod 6 is removed from the core rod insertion hole 5, the expanded portion 22 contracts in diameter and engagement between a tip surface 7S and the step surface 24D is released. After use, when the core rod 6 is removed, the expansion portion 22 closes and the main body 4 can be pulled out.SELECTED DRAWING: Figure 6

Description

Technical Field

[0001] The present invention relates to an anchor fixed to an anchor insertion hole.

Background Art

[0002] In recent years, as this type of thing, there is a floor slab lifting jig (for example, Patent Document 1) including a core rod inserted into a hole formed in a floor slab and having a first diameter-expanded portion formed at a lower end with an outer diameter smaller than the inner diameter of the hole, a cylindrical portion through which the core rod is inserted, and a diameter-expanded member having a second diameter-expanded portion that can be expanded at the lower end of the cylindrical portion, and a suspension member that suspends the diameter-expanded member at a position facing the outer surface of the core rod. The diameter-expanded member is movable along the core rod. When the cylindrical portion is caught by the first diameter-expanded portion while moving downward with respect to the core rod and the second diameter-expanded portion is expanded, the maximum value of the outer diameter of the expanded second diameter-expanded portion is larger than the inner diameter of the hole. By inserting the first diameter-expanded portion of the core rod into the hole and expanding the second diameter-expanded portion, the second diameter-expanded portion larger than the inner diameter of the hole can be hooked in the hole, and by pulling up the core rod in this state, the floor slab can be lifted with the second diameter-expanded portion hooked in the hole.

[0003] Further, as a conventional technique, there is an anchor (for example, Patent Document 2) composed of a sleeve-shaped anchor body and a core rod inserted into the anchor body. The anchor body is provided with a plurality of slits cut axially from the tip and expansion pieces divided by the slits spaced in the circumferential direction. A stepped portion is formed inside the expansion piece. When the core rod is driven in and the bullet-shaped tip portion enters the stepped portion, the expansion piece expands.

Patent Document 1

Patent Document 2

Disclosure of the Invention

Problems to be Solved by the Invention

[0004] In the jig of the above Patent Document 1, the positions where the second diameter-expanded portion gets caught in the hole are likely to vary from jig to jig, but after use, it can be pulled out and reused (Fig. 15).

[0005] On the other hand, with the anchor of Patent Document 2, it can be fixed at a certain depth in the drilling of the concrete structure, but the anchor cannot be reused.

[0006] Therefore, in view of the above problems, an object of the present invention is to provide an anchor that can be fixed at a certain position and can be repeatedly used.

Means for Solving the Problems

[0007] In order to achieve the above object, the invention according to claim 1 is an anchor inserted and fixed in an anchor insertion hole, comprising: an anchor insertion hole diameter-expanded portion provided on the tip side of the anchor insertion hole and larger than the base end portion of the anchor insertion hole; a stepped surface provided between the base end portion of the anchor insertion hole and the anchor insertion hole diameter-expanded portion; a main body having a lengthwise slit cut into the tip portion and divided, and an expansion portion provided that can be inserted into and removed from the anchor insertion hole; a mandrel insertion hole provided in the main body; a mandrel inserted into the mandrel insertion hole from the base end side; and a locking portion provided on the expansion portion having spring properties that expands in diameter by the mandrel inserted into the mandrel insertion hole and locks to the stepped surface when the expansion portion expands in diameter. When the mandrel is pulled out from the mandrel insertion hole, the expansion portion contracts in diameter and the locking between the stepped surface and the locking portion is released.

[0008] Further, the invention according to claim 2 is characterized in that the base end portion of the anchor insertion hole is constituted by a pipe body embedded and fixed in concrete.

[0009] Further, the invention according to claim 3 is characterized in that a large-diameter portion is provided at the tip of the main body, the locking portion is provided at the base end of this large-diameter portion, and the tip side of the main body is reduced in diameter toward the locking portion.

[0010] In addition, the invention according to claim 4 is characterized in that the tubular body is made of a rigid material, the front end surface of the tubular body is located on the stepped surface, and the locking portion can be locked to the front end surface of the tubular body.

Advantages of the Invention

[0011] According to the anchor described in claim 1 of the present invention, when the main body is inserted into the anchor insertion hole and the mandrel is inserted into the mandrel insertion hole from the base end side of the main body, the expansion portion is opened by the mandrel, and the locking portion of the expansion portion is locked to the stepped surface of the anchor insertion hole, and the main body can be attached to the anchor insertion hole in a state of being prevented from coming off at a position corresponding to the stepped surface of the anchor insertion hole. When working using this main body and, after the work is completed, the mandrel is removed, the expansion portion closes and the main body can be pulled out, and the main body and the mandrel can be repeatedly used.

[0012] In addition, according to the anchor described in claim 2, the base end portion of the anchor insertion hole can be provided by the tubular body without drilling a concrete member.

[0013] In addition, according to the anchor described in claim 3, the expansion portion can be expanded until the reduced diameter portion on the front end side of the main body contacts the inner peripheral surface of the anchor insertion hole.

[0014] In addition, according to the anchor described in claim 4, since the locking portion is locked to the front end surface of the tubular body made of a rigid material, the locking strength between the locking portion and the front end surface can be ensured.

Brief Description of the Drawings

[0015]

Figure 1

Figure 2

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Figure 4

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Figure 8

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Figure 15

Figure 16

Best Mode for Carrying Out the Invention

[0016] Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

Example 1

[0017] Hereinafter, Example 1 of the present invention will be described with reference to FIGS. 1 to 6. As shown in the figure, the anchor 1 of the present invention is attached to an anchor insertion hole 3 formed in a concrete member 2, and includes a main body 4 made of metal, for example, steel and having a circular cross-section, a mandrel insertion hole 5 provided at the center of the inside of the main body 4, a metal mandrel 6 inserted into the mandrel insertion hole 5 from the base end side, and a tubular body 7 made of a hard material such as metal that is attached to the concrete member 2 by an insert and whose inner peripheral surface 7N constitutes the base end portion of the anchor insertion hole 3.

[0018] Further, an enlarged diameter portion 8 of the anchor insertion hole 3 is provided on the tip side of the anchor insertion hole 3. The enlarged diameter portion 8 of the anchor insertion hole is formed by attaching a cap 11 made of metal or synthetic resin to the tip of the tubular body 7 and attaching it by an insert during the molding of the concrete member 2.

[0019] The anchor insertion hole 3 has a base end portion formed by the inner peripheral surface 7N of the tubular body 7 and a tip side formed by the enlarged diameter portion 8 of the anchor insertion hole.

[0020] The cap 11 closes the tip of a cylindrical portion 12 having a diameter larger than the inner diameter of the tubular body 7 with a tip cover plate portion 13, and forms a connecting ring portion 14 facing the center side at the base end of the cylindrical portion 12. The connecting ring portion 14 is formed in a curved shape, and its inner edge portion 14N (FIG. 4) is attached to the outer peripheral surface of the tip of the tubular body 7.

[0021] The inside of the cap 11 is the enlarged diameter portion 8 of the anchor insertion hole. Further, the tip surface 7S of the tubular body 7 and the inner surface of the connecting ring portion 14 continuous therewith are a stepped surface 15 (FIG. 4) provided between the inner peripheral surface 7N, which is the base end portion of the anchor insertion hole 3, and the enlarged diameter portion 8 of the anchor insertion hole. The tip surface 7S located on this stepped surface 15 is located on a plane orthogonal to the center line of the main body 4. Note that the tip surface 7S faces the tip side.

[0022] At the tip of the main body 4, a slit 21 is cut from the tip side, and an expanded portion 22 divided into pieces is provided. In this example, four slits 21, 21, 21, 21 are cut in the longitudinal direction of the main body 4 at substantially equal intervals in the circumferential direction from the tip side, and four expanded portions 22, 22, 22, 22 divided into pieces by these slits 21, 21, 21, 21 are provided.

[0023] The mandrel insertion hole 5 includes a base end portion 5K having a circular cross-section formed from the base end to near the tip of the main body 4, and a tip portion 5S provided between the base end portion 5K and the tip of the main body 4. The cross-sectional area of the tip portion 5S is smaller than that of the base end portion 5K. Further, a tapered reduction portion 5V is provided between the base end portion 5K and the tip portion 5S, and the reduction portion 5V, which is the tip of the base end portion 5K, is located at a position away from the tip of the main body 4 toward the base end side.

[0024] Also, the base end 21K of the slit 21 is located on the base end side of the main body 4 from the position of the reduction portion 5V, which is the tip of the base end portion 5K of the mandrel insertion hole 5, and the slit 21 communicates with the mandrel insertion hole 5. Further, the circumferential width of the slit 21 is smaller than the diameter of the mandrel insertion hole 5, and the circumferential width of the slit 21 is constant. Also, the tip portion 5S is located at the center of the plurality of slits 21, 21, 21, 21, and the diameter of the tip portion 5S is larger than the width of the slit 21. An arc portion 22E (FIG. 2) constituting a part of the tip portion 5S is formed on the center side of the main body 4 of the expansion portion 22.

[0025] On the tip side of the main body 4, a tapered portion 23 whose outer circumference shrinks is provided from the vicinity of the position of the base end 21K of the slit 21 toward the tip side. A diameter-increasing portion 24 that can be locked to the tip surface 7S of the tubular body 7 is provided at the tip of the tapered portion 23. The diameter of the diameter-increasing portion 24 is larger than that of the tip of the tapered portion 23, and a step surface 24D, which is a locking step portion at the base end of the diameter-increasing portion 24, locks to the tip surface 7S. And the step surface 24D faces the base end side. In this way, the tip side of the main body 4 has a reduced diameter from the vicinity of the position of the base end 21K of the slit 21 toward the step surface 24D.

[0026] By providing the tapered portion 23 in this manner, the thickness of the proximal end side of the expanded portion 22 becomes thinner, facilitating expansion. Also, the expanded portion 22 can expand until the outer surface of the tapered portion 23 contacts the tubular body 7 (Fig. 6). Further, a quenching process is performed on a predetermined range including the expanded portion 22. Since the expanded portion 22 has a large spring property, it will return to its original shape even if the expanded portion 22 expands as described above. Incidentally, the maximum outer diameter D of the expanded portions 22, 22, 22, 22 is substantially equal to the diameter of the outer periphery of the main body 4, and the expanded portion 22 before expansion can be inserted into the anchor insertion hole 3.

[0027] The mandrel 6 has a conical tip portion 32 formed at the tip of a rod main body 31 made of a round bar, and a head portion 33 serving as an operation portion at the proximal end of the rod main body 31. The diameter of the rod main body 31 is slightly smaller than that of the mandrel insertion hole 5, and the head portion 33 is larger than the diameter of the mandrel insertion hole 5 and smaller than the diameter of the main body 4.

[0028] Incidentally, when the head portion 33 abuts against the base end surface 4K which is the base end of the main body 4, the expanded portion 22 expands, and the stepped surface 24D engages with the tip surface 7S of the stepped surface 15.

[0029] In the main body 4, in a state of being attached to the concrete member 2, a through hole 35 in the diameter direction is formed in a portion on the proximal end side that extends to the outside, and a male screw portion 36 is formed on the outer periphery of the proximal end side.

[0030] Also, as shown in Fig. 6, when the mandrel 6 is inserted into the mandrel insertion hole 5, the expanded portion 22 expands, and the stepped surface 24D of the large diameter portion 24 engages with the tip surface 7S of the tubular body 7. In this locked state, the stepped surface 24D is in surface contact with the tip surface 7S. In the state before expansion, the stepped surface 24D is formed slightly obliquely at an angle θ with respect to a plane perpendicular to the center. After expansion, the stepped surface 24D is located on a plane perpendicular to the center line of the main body 4 and is in surface contact with the tip surface 7S.

[0031] Next, taking the case of using the anchor 1 for lifting a concrete member 2 as an example, the method of using the anchor 1 will be described. Inside the formwork (not shown) of the concrete member 2, the tubular body 7 with the cap 11 attached is fixed in position so that the base end of the tubular body 7 is located on the surface of the concrete member 2. Then, concrete is placed in the formwork, and after curing the placed concrete, the formwork is removed, and the concrete member 2 provided with the anchor insertion hole 3 is formed.

[0032] Insert the main body 4 into the anchor insertion hole 3 from the base end side until the tip of the expansion part 22 hits the tip cover plate part 13 of the cap 11. After that, insert the core bar 6 from the base end side of the core bar insertion hole 5. When the bar main body 31 enters the tip part 5S of the core bar insertion hole 5, since the tip part 5S of the core bar insertion hole 5 is smaller than the core bar 6, the expansion part 22 expands so as to open. When the head 33 abuts against the base end face 4K of the main body 4, as shown in FIG. 6, the stepped surface 24D is locked to the tip surface 7S, and the main body 4 is locked in a state where it cannot be pulled out.

[0033] Then, a female screw part such as an eyebolt (not shown) is screwed onto the male screw part 36 on the base end side of the main body 4, and the concrete member 2 can be lifted using the eyebolt.

[0034] After the lifting or movement of the concrete member 2 is completed, use the head 33 to pull out the core bar 6. When the core bar 6 is pulled out, the expansion part 22 contracts in diameter to be smaller than the inner diameter of the tubular body 7 due to its large spring property and returns to the diameter before expansion, and the locking is released, and the main body 4 can be pulled out. At this time, a jig (not shown) can be inserted into the through hole 35 to pull out the main body 4.

[0035] After use in this way, the main body 4 and the core bar 6 can be removed from the anchor insertion hole 3, and the removed main body 4 and core bar 6 can be attached to other anchor insertion holes 3 and used repeatedly.

[0036] Thus, in this embodiment, corresponding to claim 1, in the anchor 1 inserted and fixed into the anchor insertion hole 3, an anchor insertion hole diameter expansion portion 8 provided on the distal end side of the anchor insertion hole 3 and larger than the inner peripheral surface 7N which is the proximal end portion of the anchor insertion hole 3, a stepped surface 15 provided between the inner peripheral surface 7N of the anchor insertion hole 3 and the anchor insertion hole diameter expansion portion 8, a main body 4 whose tip portion is cut with a longitudinal slit 21 and divided, and an expansion portion 22 that is provided to be insertable into and removable from the anchor insertion hole 3, a mandrel insertion hole 5 provided in the main body 4, a mandrel 6 inserted into the mandrel insertion hole 5 from the proximal end side, and a stepped surface 24D which is a locking portion provided in the springy expansion portion 22 that expands by the mandrel 6 inserted into the mandrel insertion hole 5 and locks to the stepped surface 15 when the expansion portion 22 expands. When the mandrel 6 is pulled out from the mandrel insertion hole 5, the expansion portion 22 contracts and the locking between the tip surface 7S and the stepped surface 24D is released. Therefore, when the main body 4 is inserted into the anchor insertion hole 3 and the mandrel 6 is inserted into the mandrel insertion hole 5 from the proximal end side of the main body 4, the expansion portion 22 is opened by the mandrel 6, and the stepped surface 24D which is the locking portion of the expansion portion 22 locks to the stepped surface 15 of the anchor insertion hole 3, and at a position corresponding to the stepped surface 15 of the anchor insertion hole 3, the main body 4 can be attached to the anchor insertion hole 3 in a non-removable state. When working using this main body 4, and after the work is completed, when the mandrel 6 is pulled out, the expansion portion 22 closes and the main body 4 can be pulled out, and the main body 4 and the mandrel 6 can be repeatedly used.

[0037] Thus, in this embodiment, corresponding to claim 2, since the inner peripheral surface 7N which is the proximal end portion of the anchor insertion hole 3 is constituted by a pipe body 7 embedded and fixed in the concrete, the proximal end portion of the anchor insertion hole 3 can be provided by the pipe body 7 without drilling the concrete member 2.

[0038] Thus, in this embodiment, corresponding to claim 3, a large-diameter portion 24 is provided at the tip of the main body 4, and a stepped surface 24D which is a locking portion is provided at the proximal end of this large-diameter portion 24. Since the tip side of the main body 4 tapers toward the stepped surface 24D, the expansion portion 22 can be expanded until the tapered portion on the tip side of the main body 4 contacts the inner peripheral surface 7N of the anchor insertion hole 3.

[0039] Thus, in this embodiment, corresponding to claim 4, the tubular body 7 is made of a rigid material, the tip surface 7S of the tubular body 7 is located on the stepped surface 15, the stepped surface 24D serving as the locking portion can be locked to the tip surface 7S of the tubular body 7, and since the stepped surface 24D serving as the locking portion is locked to the tip surface 7S of the tubular body 7 made of a rigid material, the locking strength between the stepped surface 24D and the tip surface 7S can be ensured.

[0040] Hereinafter, as an effect in the embodiment, a large-diameter cap 11 is provided at the tip of the tubular body 7 constituting the base end portion of the anchor insertion hole 3, so that the anchor insertion hole 3 having the tip surface 7S serving as a stepped surface can be easily formed in the concrete member 2. Further, since a tapered reduction portion 5V is provided between the base end portion 5K and the tip portion 5S of the mandrel insertion hole 5, the expanded portion 22 can be greatly expanded in diameter by pushing open the reduction portion 5V with the mandrel 6.

[0041] Also, on the outer periphery of the main body 4, a tapered portion 23 whose outer periphery is reduced is provided from the position of the base end 21K of the slit 21 toward the large-diameter portion 24 on the tip side. Therefore, the thickness on the base end side of the expanded portion 22 becomes thin and it becomes easy to expand. In addition, as shown in FIG. 6, the expanded portion 22 can be greatly expanded until the outer surface of the tapered portion 23 abuts or approaches the tubular body 7. Further, in the state before expansion, the stepped surface 24D is formed slightly obliquely at an angle θ with respect to a plane orthogonal to the center, and after expansion, the stepped surface 24D is located on a plane orthogonal to the center line of the main body 4 and is in surface contact with the tip surface 7S, so that the anti-loosening strength can be improved. In addition, since the expanded portion 22 has a large spring property, when the mandrel 6 is removed, the expanded portion 22 returns to its original shape.

Embodiment 2

[0042] FIGS. 7 to 12 show Embodiment 2 of the present invention. The same parts as those in the above Embodiment 1 are denoted by the same reference numerals, and the detailed description thereof is omitted. In this example, an example in which the expanded portion 22 is bent and reduced in diameter is shown.

[0043] As shown in FIG. 7, the slit 21 is formed wider and the height of the large-diameter portion 24 is increased as compared with Embodiment 1.

[0044] Then, as shown in FIG. 7, after the processing of the expanding portions 22 such as the mandrel insertion holes 5, the tapered portions 23, the large-diameter portions 24, and the slits 21 is completed, as shown in FIGS. 9 and 10, the tip side of the expanding portion 22 is bent by hot or cold working so as to approach the center of the main body 4, and then quenching is performed. By this bending process, between the position of the base end 21K of the thin-walled slit 21 and the position of the reduced portion 5V which is the tip of the mandrel insertion hole 5 in the expanding portion 22, the expanding portion 22 bends with a large radius of curvature, the tips of the slits 21 approach each other, and the tip sides of the expanding portions 22, 22, 22, 22 approach each other.

[0045] Also, by the bending process, the tip side of the base end portion 5K of the mandrel insertion hole 5 is slightly reduced in diameter toward the reduced portion 5V. Also, the tip portion 5S of the mandrel insertion hole 5 is formed between the corner portions 22K, 22K, 22K, 22K which are the center portions of the main body 4 of the four expanding portions 22, 22, 22, 22. And the maximum outer diameter D after the bending process is smaller than the inner diameter of the inner peripheral surface 7N of the anchor insertion hole 3. Incidentally, at the tip of the main body 4, the slit 21 may be closed. Also, as in the first embodiment, the corner portion 22K may be formed into an arc portion 22E so that the tip of the tip portion 5S opens at the tip of the main body 4.

[0046] Also, in this example, on the inner surface of the connecting ring portion 14, a straight portion continuous with the tip surface 7S of the pipe body 7 is provided, and this straight portion and the tip surface 7S are located on the same plane. Incidentally, as in the first embodiment, the stepped surface 24D engages and disengages with the tip surface 7S.

[0047] Then, in the same manner as in the first embodiment above, by an insert, the pipe body 7 with the cap 11 attached to the concrete member 2 is buried and fixed to form the anchor insertion hole 3, the main body 4 is inserted into this anchor insertion hole 3, the mandrel 6 is inserted from the base end side of the main body 4 to expand the diameter of the expanding portion 22, the large-diameter portion 24 is locked to the tip surface 7S located on the stepped surface 15 (FIG. 11), and the main body 4 is attached to the anchor insertion hole 3.

[0048] Using the main body 4 attached to the concrete member 2, the concrete member 2 is lifted, or used by attaching other members to the concrete member 2. After movement or after using other members, the mandrel 6 can be removed, the locking can be released, and the tubular body 7 can be pulled out. Further, the pulled-out mandrel 6 and the main body 4 can be repeatedly used.

[0049] Thus, also in this embodiment, corresponding to all the claims, the same operations and effects as those in the above-described Embodiment 1 are exhibited.

[0050] Further, as an effect in the embodiment, after providing the tapered portion 23 in the main body 4, the expanding portions 22, 22, 22, 22 are reduced in diameter by bending, so that the height of the stepped surface 24D can be increased and the retaining strength can be improved, and even a heavy concrete member 2 can be lifted.

Embodiment 3

[0051] FIG. 13 shows Embodiment 3 of the present invention. The same parts as those in the above-described embodiments are denoted by the same reference numerals, and a detailed description thereof will be omitted. In this example, a cap 11 without a connecting ring portion 14 is used.

[0052] The inner peripheral surface 12N of the cylindrical portion 12 of the cap 11 is fixed to the outer periphery of the tip of the tubular body 7. If the cap 11 is made of synthetic resin, it can be fixed by a fixing portion 41 using an adhesive or the like, and if the cap 11 is made of metal, it can be fixed by a fixing portion 41 using welding or the like. And the main body 4 having the same configuration as that of Embodiment 1 is used. In this example, since there is no connecting ring portion 14, the stepped surface 15 is composed of only the tip surface 7S.

[0053] Thus, also in this embodiment, corresponding to all the claims, the same operations and effects as those in the above-described embodiments are exhibited.

[0054] Further, as an effect in the embodiment, by fixing the inner peripheral surface 12N of the cylindrical portion 12 of the cap 11 to the outer periphery of the tip of the tubular body 7, it becomes easy to attach the cap 11 to the tubular body 7.

Embodiment 4

[0055] Figures 14 to 16 show Example 4 of the present invention. The same parts as those in the above examples are denoted by the same reference numerals, and detailed descriptions thereof are omitted. To describe in detail, in this example, the configuration of the main body 4 is simplified compared to Examples 1 and 2.

[0056] As shown in the figure, on the main body 4 made of a steel pipe or the like having a certain thickness, a flange-shaped large-diameter portion 24 is provided around the outer periphery of the tip of the main body 4, and the stepped surface 24D is formed by the surface on the base end side of the large-diameter portion 24. Incidentally, before the bending process described later, the maximum outer diameter D of the large-diameter portion 24 is substantially equal to the outer diameter of the main body 4. Further, as shown in the figure, in this example, the tapered portion 23 is not provided.

[0057] At the tip of the main body 4, the slits 21 are cut from the tip side, and four of the expanded portions 22, 22, 22, 22 that are split into pieces are provided. After these expanded portions 22 are bent, quenching is performed.

[0058] As shown in FIG. 14, after the bending process of the expanded portion 22, the expanded portions 22, 22 adjacent to each other in the circumferential direction at the tip are close to each other, or the slit 21 is closed at the tip, and the maximum outer diameter D of the expanded portion 22 becomes smaller than the inner diameter of the pipe body 7, and the main body 4 can be inserted into the pipe body 7.

[0059] Although not shown, similar to Example 1, at the base end of the mandrel 6, the head 33 smaller than the outer diameter of the pipe body 7 is provided, and in the state where the main body 4 is attached to the concrete member 2, a through hole 35 in the diameter direction is formed in a portion on the base end side that extends to the outside, and the male screw portion 36 is formed on the outer periphery of the base end side of the main body 4.

[0060] Further, the tip portion 32A of the rod main body 31 is formed in a truncated conical shape that becomes thinner toward the tip side.

[0061] And, similar to each of the above embodiments, by means of the insert, a tubular body 7 with a cap 11 attached to the concrete member 2 is buried and fixed to form an anchor insertion hole 3. The main body 4 is inserted into this anchor insertion hole 3, the mandrel 6 is inserted from the proximal end side of the main body 4 to expand the diameter of the expansion part 22, the large-diameter part 24 is locked to the tip surface 7S located on the stepped surface 15, and the main body 4 is attached to the anchor insertion hole 3. In FIG. 16, for the sake of explanation, only the expansion part 22 in the upper right of the figure is shown at an enlarged position.

[0062] Using the main body 4 attached to this concrete member 2, the concrete member 2 can be lifted, or another member can be attached to the concrete member 2. After movement or after the use of another member, the mandrel 6 can be removed, the locking can be released, and the tubular body 7 can be pulled out. Also, the pulled-out mandrel 6 and the main body 4 can be repeatedly used.

[0063] Thus, also in this embodiment, corresponding to all the claims, the same operations and effects as those of the above embodiments are achieved.

[0064] Also, as an effect of the embodiment, since a steel pipe with a certain thickness is used for the main body 4, after providing the large-diameter part 24 in the steel pipe and forming the slit 21, it is bent and then quenched, so that the main body 4 can be easily manufactured.

[0065] As described above, the embodiments of the present invention have been described in detail. However, the present invention is not limited to the above embodiments, and various modifications can be made within the scope of the gist of the present invention. For example, in the embodiment, the number of expansion parts is four, but two or more are sufficient. Also, the tubular body may be made of a hard material on the tip side. Furthermore, it may be combined with the configurations of each embodiment. For example, the main body of Embodiments 1 and 3 may be bent.

Explanation of Reference Numerals

[0066] 1 Anchor 2 Concrete Member 3 Anchor Insertion Hole 4 Main Body 5 Mandrel Insertion Hole 6 Mandrel 7 Tubular Body 7N Inner circumferential surface (base end portion of anchor insertion hole) 7S Tip surface (step surface of anchor insertion hole) 8 Anchor insertion hole diameter expansion portion 15 Step surface 21 Slit 22 Expansion portion 23 Taper portion 24 Large diameter portion 24D Step surface (locking portion)

Claims

1. An anchor to be inserted and fixed into an anchor insertion hole, an anchor insertion hole diameter expansion part provided on the tip side of the anchor insertion hole and larger than the base end part of the anchor insertion hole, a stepped surface provided between the base end part of the anchor insertion hole and the anchor insertion hole diameter expansion part, a main body with a lengthwise slit cut into the tip part and divided, and an expansion part provided that can be inserted into and removed from the anchor insertion hole, a mandrel insertion hole provided in the main body, a mandrel inserted into the mandrel insertion hole from the base end side, a locking part provided on the expansion part having spring properties that expand in diameter by the mandrel inserted into the mandrel insertion hole, and that locks to the stepped surface when the expansion part expands in diameter, The anchor is characterized in that when the mandrel is pulled out of the mandrel insertion hole, the expansion part contracts in diameter and the locking between the stepped surface and the locking part is released.

2. The anchor according to claim 1, characterized in that the base end part of the anchor insertion hole is constituted by a pipe body embedded and fixed in concrete.

3. The anchor according to claim 1, characterized in that a large diameter part is provided at the tip of the main body, the locking part is provided at the base end of this large diameter part, and the tip side of the main body contracts in diameter toward the locking part.

4. The anchor according to claim 2, characterized in that the pipe body is made of a hard material, the tip surface of the pipe body is located at the stepped surface, and the locking part can lock to the tip surface of the pipe body.

Images