JP2014062361A - Post-installed anchor set - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a post-installed anchor set capable of obtaining a stable fixation strength through simple installation work.SOLUTION: A post-installed anchor set comprises an anchor bolt 10, a sleeve 40, a washer 20 and a nut 30. In the anchor bolt 10, a bolt head 11 is formed in a tapered shape so as to be narrow towards a distal end of a bolt shank, and a male screw 14 is formed in a first half of the bolt shank. A pin tail 15 is formed in the distal end of the bolt shank via a notch 16 which is fractured by a predetermined torque, and the anchor bolt 10 is inserted from the bolt head into a mounting hole 51 which is opened on a ground 50. The sleeve 40 is tapered on an inner surface 41 of a distal end portion and externally covers the bolt shank. The washer 20 is abutted with an upper end of the sleeve, and the nut 30 is threaded with the male screw of the anchor bolt and abutted to the washer. By relatively revolving the nut and the pin tail, the sleeve relatively rides on the bolt head and is expanded and pressed against an inner surface of the mounting hole, and the pin tail is fractured at the notch when reaching the predetermined torque.

Description

  The present invention relates to a post-installed anchor set, and more particularly to an anchor set that can obtain a stable fixing force by a simple construction work.

  For example, post-installed anchor bolts are often used when installing devices and structures. For anchor bolts to be installed after this, a method is adopted in which mounting holes are drilled in concrete ground (including concrete foundations, floor boards, rocks, etc.), and anchor bolts are inserted into the mounting holes and fixed with mortar or adhesive. However, since the anchor bolt is inserted and fixed in the linear mounting hole, it is difficult to obtain a sufficiently large resistance against the upward pulling out of the anchor bolt.

  In contrast, one or a plurality of enlarged diameter portions are provided on the inner surface of the mounting hole drilled in the ground, the anchor reinforcing bar is inserted into the mounting hole, and the adhesive is filled between the anchor reinforcing bar and the inner surface of the mounting hole. A method of making it solidify is known (Patent Document 1).

  However, in this construction method, the anchoring reinforcement of the anchor rebar depends on the peripheral surface friction with the adhesive, so the anchor rebar may be separated from the adhesive and stable pull-out resistance may not be obtained. there were.

  In addition, a plurality of cut pieces are provided by forming a cut along the axial direction on the distal end side of the hollow anchor bolt, a reduced diameter portion is provided inside, a mounting hole is drilled in the ground, and a mounting hole is formed in the mounting hole. A method has been proposed in which an anchor bolt is inserted and a pin is driven into the anchor bolt so that the cut piece is expanded outward and the anchor bolt is pressed into the mounting hole and fixed (Patent Document 2).

  However, since it is necessary to form a pin insertion hole in the center of the anchor bolt, not only the strength of the anchor bolt itself is low, but also when the mounting hole is formed in a rock or the like, the cut piece cannot be expanded sufficiently. It is difficult to obtain a sufficiently large pulling resistance.

  An anchor bolt with an enlarged head at the tip is externally mounted with a fixing material having a plurality of slits and a cylindrical jig, and a mounting hole is drilled in the ground, and a taper-shaped expansion is formed at the bottom of the mounting hole. The diameter part is stepped, the anchor bolt is inserted into this mounting hole, the nut is screwed into the male screw of the anchor bolt, and the nut is rotated to advance the fixing material and ride on the enlarged head to expand it. Open and press firmly against the inner surface of the tapered enlarged diameter part of the mounting hole, then remove the nut and cylindrical jig and fill the space between the anchor bolt and the mounting hole with a solidifying material to obtain a sufficiently large pulling resistance A post-process anchor set has been proposed (Patent Document 3).

Japanese Patent Laid-Open No. 03-25120 Japanese Patent Laid-Open No. 04-73321 Japanese Patent Application Laid-Open No. 07-1192109

  However, in the post-process anchor set described in Patent Document 3, the anchor bolt fixing force varies not only depending on the degree of expansion of the fixing material, but also the anchor bolt structure is complicated and construction work is complicated. Become.

  In view of such problems, an object of the present invention is to provide a post-installation anchor set in which a fixing force having a desired size can be stably obtained by a simple construction work.

  The post-installed anchor set according to the present invention is formed in a taper shape such that the bolt head narrows toward the tip of the bolt shaft portion, a male screw is formed in the front half portion of the bolt shaft portion, and the tip of the bolt shaft portion is formed. The pin tail is formed through a notch that is broken by a predetermined torque, and an anchor bolt that is inserted from the bolt head into a mounting hole drilled in the ground, and a taper is formed on the inner surface of the tip, and is externally mounted on the bolt shaft. A sleeve, a washer that is in contact with the upper end of the sleeve, and a nut that is screwed into the male screw of the anchor bolt and is in contact with the washer, and the nut and pin tail are relatively rotated. As a result, the sleeve relatively rides on the bolt head and expands and is pressed against the inner surface of the mounting hole, and the pin tail is knocked when a predetermined torque is reached. In is characterized in that no such be broken.

  One of the features of the present invention is that the bolt head of the Torcia bolt is tapered, the sleeve is externally mounted on the bolt shaft, the inner surface of the tip of the sleeve is tapered, and the nut and pin tail are rotated relative to each other. The sleeve is advanced and the tip of the sleeve rides on the bolt head to expand, and the expanded portion of the sleeve is pressed against the inner surface of the mounting hole.

  Thereby, when the pressing force against the inner surface of the mounting hole of the expanding portion of the sleeve reaches a predetermined magnitude, the notch of the pin tail breaks due to the resistance due to the pressing, so that the predetermined fixing force can be stably obtained. The reliability of the anchor can be greatly improved.

  In addition, it is composed of four parts: a torcia type bolt, a sleeve, a washer, and a nut. The structure is simple and the anchor can be installed by a very simple operation.

  The sleeve may be simply cylindrical, but a plurality of slits extending in the axial direction may be formed in the tapered portion of the sleeve so as to be easily expanded.

  The taper of the sleeve is a taper of the same angle as the taper of the bolt head, but if the taper of the angle is larger than the taper of the bolt head, the tip of the sleeve can be expanded further and pressed more firmly against the inner surface of the mounting hole. And a sufficiently large fixing force can be obtained more stably.

  The outer surface of the taper portion of the bolt head and the inner surface of the taper portion of the sleeve form splines that extend in the axial direction and are engaged with each other. With this, the bolt is pulled up while the inner surface of the mounting hole is being scraped off, whereby a more stable fixing force can be obtained.

It is a block diagram which shows preferable embodiment of the post-installation anchor set which concerns on this invention. It is a figure which shows typically the construction work in the said embodiment. It is a figure which shows the anchor set after construction in the said embodiment.

  Hereinafter, the present invention will be described in detail based on specific examples shown in the drawings. 1 to 3 show a preferred embodiment of a post-process anchor set according to the present invention. In the figure, the anchor set of this example is composed of an anchor bolt 10, a washer 20, a nut 30 and a sleeve 40.

  The anchor bolt 10 is composed of a bolt head 11 and a bolt shaft portion. The bolt head 11 is formed in a taper 12 narrowed toward the tip of the bolt shaft portion, and a male screw 14 is formed on the tip half of the bolt shaft portion. The pin tail 15 is formed at the tip of the bolt shaft portion through a notch 16 that is broken by a predetermined torque.

  Further, a cylindrical sleeve 40 is externally mounted on the bolt shaft portion, and a taper having a size equal to the taper 12 of the bolt head 11 is formed on the inner surface 41 of the tip (bolt head side) of the sleeve 40, A plurality of slits (not shown) extending in the axial direction are formed in the tapered portion 41 of the sleeve 40 at intervals.

  Further, a washer 20 is externally mounted on the bolt shaft portion, the washer 20 is brought into contact with the upper end of the sleeve 40, and a nut 30 is screwed on the male screw 14 of the anchor bolt 10, and its seating surface comes into contact with the washer 20. Has been.

  Splines 13 that can be engaged with each other are formed on the outer surface of the tapered portion 12 of the bolt head 11 and the inner surface of the tapered portion 41 of the sleeve 40.

  When an anchor is installed on the ground 50, as shown in FIG. 2A, after a mounting hole 51 is drilled by a drill 60 in the installation location, a bolt set is installed as shown in FIG. 2B. Is inserted into the mounting hole 51 from the bolt head 11.

  Next, the nut 20 and the pin tail 15 of the anchor bolt 10 are each gripped by a wrench, the nut 20 is prevented from rotating, and the pin tail 15 is rotated. Then, as the pin tail 15 rotates, the anchor bolt 10 is gradually pulled up, and when the anchor bolt 10 is pulled up to some extent, the taper portion 41 of the sleeve 40 is relative to the taper portion 12 of the bolt head 11 of the anchor bolt 10. Ride and expand.

  When the nut 20 is stopped and the pin tail 15 is further rotated, the tapered portion 41 of the sleeve 40 completely rides on the tapered portion 12 of the bolt head 11 of the anchor bolt 10 as shown in FIG. Further, the tapered portion 41 of the sleeve 40 is further expanded and strongly pressed against the inner surface of the mounting hole 51.

  At the same time, since the spline 13 of the taper portion 41 of the sleeve 40 is engaged with the spline 13 of the taper portion 12 of the bolt head 11 of the anchor bolt 10, when the nut 20 is stopped and the pin tail 15 is further rotated, the sleeve The expanded taper portion 41 of 40 rotates together with the bolt head 11 while scraping the inner surface of the mounting hole 51, whereby a large fixing force can be obtained.

  When the pin tail 15 is further rotated by stopping the rotation of the nut 20 and a predetermined torque is reached, as shown in FIG. 3, the pin tail 15 is broken from the notch 16, so that when the nut 30 and the washer 20 are removed, An anchor having a predetermined fixing force can be constructed.

  In the above description, the taper of the sleeve 40 is a taper having the same angle as the taper of the bolt head 11. However, if the taper of the sleeve 40 is larger than the taper of the bolt head 11, the tip end portion of the sleeve 40 is further expanded and the mounting hole 51 can be pressed more strongly to the inner surface, and a sufficiently large fixing force can be obtained more stably.

DESCRIPTION OF SYMBOLS 10 Anchor bolt 11 Bolt head 12 Tapered part 13 Spline 14 Male thread 15 Pin tail 16 Notch 20 Washer 30 Nut 40 Sleeve 41 Tapered part 50 Ground 51 Mounting hole

Claims (4)

The bolt head (11) is formed in a taper shape so as to narrow toward the tip of the bolt shaft, a male screw (14) is formed in the front half of the bolt shaft, and the pin tail (15) is formed at the tip of the bolt shaft. An anchor bolt (10) which is formed through a notch (16) which is broken by a predetermined torque and is inserted from a bolt head (11) into a mounting hole (51) drilled in the ground (50),
A taper is formed on the inner surface (41) of the tip part, and a sleeve (40) is provided on the bolt shaft part,
A washer (20) in contact with the upper end of the sleeve (40);
A nut (30) screwed into the male screw (14) of the anchor bolt (10) and brought into contact with the washer (20);
When the nut (30) and the pin tail (15) are relatively rotated, the sleeve (40) rides on the bolt head (11) and is expanded and the mounting hole (51 The post-installed anchor set is characterized in that the pin tail (15) is broken at the notch (16) when a predetermined torque is reached.   The post-installed anchor set according to claim 1, wherein a plurality of slits extending in the axial direction are formed in the tapered portion of the sleeve (40).   The post-installed anchor set according to claim 1, wherein the taper of the sleeve (40) has a larger angle than the taper of the bolt head (11).   Splines (13) extending in the axial direction and engaged with each other are formed on the outer surface of the tapered portion (12) of the bolt head and the inner surface of the tapered portion (41) of the sleeve (40). When the diameter of (40) rides on the bolt head (11) and is expanded to be pressed against the inner surface of the mounting hole (51), the spline (13) is engaged with each other so that the bolt shaft portion The post-installed anchor set according to claim 1, wherein the sleeve (40) and the sleeve (40) are rotated together.

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