JP2005220963A - Anchor bolt - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an anchor bolt capable of simply and accurately inserting into a constructed hole drilled into a concrete body. <P>SOLUTION: The anchor bolt is provided with a narrow diameter thread section 6 formed at a lower part of a large diameter bolt 5, a fixed member 2 and an expansion sleeve 3 loosely fitted on the narrow diameter thread section 6, and a push-up nut 4 engaged with the narrow diameter thread section 6. The fixed member 2 is formed on a tapered portion 7 with a plurality of steps in which its side peripheral face is tapered downward in diameter, and is formed so that an envelope surface 8 connecting the maximum diameters among respective tapered portions is tapered downward in diameter. Further, a stripe of a thin-walled recess 6 is formed in an axis direction. The expansion sleeve 3 is cylindrical, and a plurality of slits 15 are arranged on the side peripheral face from one end to the vicinity of other end at an axis direction. The push-up nut 4 is formed into a conical shape at its upper part. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an anchor bolt used for fixing other members to a concrete frame.

  Conventionally, when fixing other members to a concrete frame, a diameter-expanding portion that tapers toward the bottom of the hole is provided on the peripheral surface near the bottom of the hole drilled in the concrete surface. A method is widely known in which an expansion sleeve attached to the tip of a bolt is expanded and fixed, an anchor bolt is installed in a construction hole, and other members are fixed using this anchor bolt (Patent Document 1). ).

In this type of anchor bolt, as a means for expanding the expansion sleeve, for example, as in Patent Document 1, a pressing cylinder containing the bolt is driven into the construction hole from above with a hammer or the like. The expansion sleeve attached to the lower end portion of the bolt is pressed downward and expanded while being moved along the tip diameter-expanded tapered surface of the anchor bolt.
Japanese Patent No. 2544021

  The above-mentioned conventional anchor bolt has a pressing cylinder inserted so as to contain the anchor bolt, and the construction hole is drilled according to the outer diameter of the pressing cylinder larger than the outer diameter of the anchor bolt. The diameter of the bolt protruding from the opening of the construction hole is smaller than the diameter of the drilled construction hole, so when drilling from above the installation with holes, the gap between the protruding bolt and the hole of the installation In the unlikely event that a lateral displacement occurs in the attachment, a large displacement width will occur.

  In addition, when the above-mentioned conventional anchor bolt is to be installed on the ceiling surface, the anchor bolt is inserted into the drilled construction hole and hit with a hammer or the like, but until the expansion sleeve expands Since the anchor bolt comes out of the construction hole due to its own weight and falls, there is a problem that it is necessary to hold the anchor bolt and the construction work becomes difficult.

  Further, in the case where the separated piece is bundled with a bundling strip having elasticity such as the deployment sleeve of Patent Document 1, the bundling strip is applied when a tensile force is applied to the anchor bolt after the expansion sleeve is expanded. Are likely to break apart and vary in the degree of fixation for each deployment piece, and may not be able to exhibit stable tensile strength.

  This invention is made | formed in view of the said point, and makes it a subject to provide the anchor bolt which can be applied to a concrete frame simply and correctly.

In order to solve the above-described problem, the anchor bolt of the present invention has a small-diameter screw portion formed in a lower portion of a large-diameter bolt, a fixing member and an expansion sleeve are loosely fitted in the thin-diameter screw portion, and the thin-diameter screw portion A push-up nut is screwed onto the screw.
The fixing member is formed to have a plurality of tapers whose side peripheral surfaces are reduced in diameter downward, and an envelope surface connecting the maximum diameters of these tapers is formed to be reduced in diameter downward. In the side peripheral surface, a thin thin recess is formed in the axial direction.

The expansion sleeve has a cylindrical shape, and the side circumferential surface may be provided with a plurality of slits extending from one end to the vicinity of the other end in the axial direction. A circumferential groove is provided, and the upper cylinder and the lower cylinder are connected via the circumferential groove, and a plurality of slits are provided in the axial direction on the side circumferential surface of the lower cylinder. Good.
Further, the expansion sleeve may be formed with a chamfered portion at the inner peripheral edge of the distal end of the extended piece formed between the plurality of slits, and a push-up nut locking groove may be provided in the chamfered portion. Good. The push-up nut may be formed conically at the top.

  In the anchor bolt of the present invention, since the fixing member can be reduced in diameter, if the maximum outer diameter of the large-diameter bolt, expansion sleeve, and push-up nut, which is a member other than the fixing member, is slightly smaller than the construction hole. The anchor bolt can be inserted into the construction hole and installed, and even when drilled from above the hole of the attachment, the gap between the bolt protruding from the opening of the construction hole and the hole of the attachment can be reduced. In the unlikely event that a lateral displacement occurs in the attachment, a large displacement width can be prevented. Furthermore, it can be easily applied to the ceiling surface.

An embodiment of the present invention will be described with reference to the accompanying drawings.
FIG. 1 is a front view showing an anchor bolt of the present invention, and FIG. 2 is a front view showing an anchor bolt body of the present invention. 3A and 3B show a fixing member constituting the anchor bolt of the present invention, wherein FIG. 3A is a plan view and FIG. 3B is a partial sectional front view. FIG. 4 shows an expansion sleeve constituting the anchor bolt of the present invention, where (a) is a partial sectional front view and (b) is a bottom view. FIG. 5 shows another expansion sleeve of the present invention, in which (a) is a partial sectional front view and (b) is a bottom view. FIG. 6 is a partial sectional front view of a push-up nut constituting the anchor bolt of the present invention.

As shown in FIGS. 1 and 2, the anchor bolt of the present invention includes an anchor bolt main body 1, a fixing member 2, an expansion sleeve 3 and a push-up nut 4.
The anchor bolt main body 1 has a small-diameter threaded portion 6 formed below the large-diameter bolt 5. The small-diameter threaded portion 6 has a cylindrical fixing member 2 extending from the lower end toward the large-diameter bolt 5. Similarly, a cylindrical expansion sleeve 3 is attached in a loose fit in order, and a push-up nut 4 is screwed.

The fixing member 2 is a hard flexible member such as a synthetic resin or a synthetic rubber. As shown in FIGS. 3 (a) and 3 (b), the fixing member 2 has a plurality of steps whose side peripheral surfaces are reduced in diameter downward. An envelope surface 8 formed on the taper 7 and connecting the maximum diameters of the plurality of tapers 7 is formed to have a diameter reduced downward.
The fixing member 2 is mounted loosely on the small-diameter threaded portion 6 of the anchor bolt body 1 with the upper end 9 on the large-diameter bolt 5 side of the anchor bolt body 1 and the lower end 10 on the expansion sleeve 3 side. However, the upper end portion 9 is in contact with the step wall 11 at the boundary between the large-diameter bolt 5 and the small-diameter screw portion 6 and cannot move to the large-diameter bolt 5 side. Therefore, the inner diameter of the hollow portion 12 of the fixing member 2 is formed smaller than the outer diameter of the large-diameter bolt 5. Further, on the side peripheral surface of the fixing member 2, a single thin recess 13 is formed in the axial direction.

  The expansion sleeve is a metal cylinder. For example, as shown in FIGS. 4 and 5, the hollow portion is loosely attached to the small-diameter threaded portion 6 of the anchor bolt main body 1, and the expansion sleeve 3. A plurality of slits 15 are provided at equal intervals in the axial direction on the side peripheral surface 14 of 3a, and expansion pieces 16 are formed between the slits 15, respectively.

  The expansion sleeve 3 shown in FIG. 4 has a configuration in which the slit 15 extends from one end on the lower end side of the small-diameter screw portion 6 to the vicinity of the upper end that is the other end on the large-diameter bolt 5 side. A chamfered portion 17 for facilitating reception of the tip end portion of the push-up nut 4 is formed in the portion.

  In the expansion sleeve shown in FIG. 5, a circumferential groove 18 is provided in the center of the side circumferential surface 14, and the upper cylinder 19 and the lower cylinder 20 are connected via the circumferential groove 18, and this lower cylinder. A plurality of slits 15 are provided at equal intervals in the axial direction on the side peripheral surface of 20. In this expansion sleeve 3 a, all the slits 15 are configured from the lower end of the lower cylinder 20 to the circumferential groove 18.

  In the expansion sleeve 3 a, as in the expansion sleeve 3 shown in FIG. 4, the expansion pieces 16 are formed between the slits 15, and the chamfered portion 17 formed at the inner peripheral edge of the distal end of the expansion piece 16 includes A push-up nut locking groove 21 is provided.

  As shown in FIG. 6, the push-up nut 4 is a metal cylinder having an upper part formed in a conical shape, and is screwed into the small-diameter threaded portion 6 of the anchor bolt body 1 from the conical side. By rotating in the direction, the expansion sleeve attached to the small-diameter screw portion 6 in a loose-fitting manner is pressed toward the large-diameter bolt 5 side.

The expansion sleeves 3, 3 a, the push-up nut 4, and the lower end portion 10 of the fixing member 2 have substantially the same outer peripheral diameter, and are usually larger than the outer diameter of the large-diameter bolt 5 of the anchor bolt body 1, for example, a construction hole Is larger by about 3.3 mm. The maximum diameter of the fixing member 2 is formed to be about 8 mm larger than the outer diameter of the large-diameter bolt 5 of the anchor bolt main body 1.
In addition, since the fixing member 2 has a shape capable of reducing the diameter, even if the construction hole is enlarged by about 1 mm due to the influence of the aggregate or the like during drilling, the fixing member has a function of reliably holding the position in the pilot hole. Construction is possible to achieve.

Hereinafter, the procedure for constructing the anchor bolt of the present invention shown in FIG. 1 on the concrete frame will be described with reference to FIG.
First, as shown to Fig.7 (a), it drills by the prescribed depth in the designated position of a concrete frame, the construction hole 25 is formed, and the chip etc. which arose in the construction hole 25 are removed.
The inner diameter of the construction hole 25 is formed to be smaller than the maximum diameter of the fixing member 2, and desirably, the diameter is such that the expansion sleeve 3 and the push-up nut 4 can be slidably inserted.
Further, as shown in FIG. 7B, the enlarged diameter portion 27 is formed on the peripheral surface of the working hole 25 with the specified depth A by using the enlarged diameter drill 26, and chips generated in the working hole 25. Remove.

The diameter-expansion drill 26 is configured such that a protruding blade 30 protrudes and protrudes from a slit 29 formed on a lower peripheral side surface of a pipe-shaped rotating shaft body 28, and is provided on an upper portion of the rotating shaft body 28. When the pressing table 32 connected by the elastic member is pressed from above and the pressing table 32 and the receiving table 31 are in contact with each other, the protruding blade 30 is completed to protrude.
Therefore, the enlarged-diameter portion 27 in the construction hole 25 is inserted and rotated by inserting the diameter-expansion drill 26 into the construction hole 25, and the pressing base 32 is slowly pushed in until it comes into contact with the receiving base 31, until the resistance during rotation disappears. This can be easily formed.

Next, as shown in FIG. 7 (c), the anchor bolt in which the fixing member 2 and the expansion sleeve 3 are loosely fitted to the small-diameter threaded portion 6 of the anchor bolt main body 1 and the push-up nut 4 is screwed is pressed. Insert into the construction hole 25 from the raising nut 4.
The anchor bolt is inserted into the construction hole 25 in the order of the push-up nut 4 and the expansion sleeve 3, but the insertion is stopped near the lower end of the fixing member 2 having an outer diameter larger than the inner diameter of the construction hole 25. To do.

From this, the upper end of the anchor bolt body 1 is struck with an anchor hammer 35,
The anchor bolt main body 1 is inserted until the washer 36 passed through the large-diameter threaded portion 5 of the anchor bolt main body 1 and the screwed nut 37 abut against the concrete casing at the opening of the construction hole 25.
At this time, the screwing stop position of the nut 37 to the anchor bolt main body 1 is previously set to a position obtained by adding the thickness of the washer 36 to the specified depth A of the construction hole 25 described above.

  As the anchor bolt main body 1 is inserted into the construction hole 25 by hitting the anchor hammer 35, the fixing member 2 is deformed in a direction to crush the single thin recessed portion 13 formed on the side peripheral surface thereof. The diameter will be adapted to the diameter of the construction hole. Thereby, the anchor bolt main body 1 is fixed on the axial center in the construction hole 25.

Next, as shown in FIG. 7D, the nut 37 is rotated by a spanner or the like and tightened.
When the nut 37 is tightened, the anchor bolt main body 1 rises on the concrete surface, and at the same time, the push-up nut 4 screwed into the small-diameter threaded portion 6 of the anchor bolt main body 1 also rises, and its conical shape. The distal end portion of the expansion sleeve 3 enters the gap between the expansion sleeve 3 and the small-diameter screw portion 6, and the tapered surface of the conical distal end portion expands the expansion piece 16 of the expansion sleeve 3 in a sliding manner. It is pressed and fixed in the enlarged diameter portion 27 of the hole 25.
Thereby, the anchor bolt of the present invention is firmly fixed on the axial center in the construction hole 25.

  Moreover, when constructing the anchor bolt of the present invention using the expansion sleeve 3a shown in FIG. 5 on the concrete frame, the construction hole 25 is formed in the same manner as the anchor bolt described above based on FIGS. 7 (a) to (c). Then, a diameter-expanded portion 26 is formed in the construction hole 25 by the diameter-expansion drill 26, an anchor bolt is inserted into the construction hole 25, and an anchor hammer 35 is struck to form an axial center in the construction hole 25. Then, the nut 37 is tightened, and the anchor bolt body 1 is raised on the concrete surface.

  As the anchor bolt main body 1 rises, as shown in FIG. 8, when the push-up nut 4 screwed into the small-diameter threaded portion 6 of the anchor bolt main body 1 also rises, the upper conical tip of the push-up nut 4 However, it enters into the gap between the lower cylindrical body 20 of the expansion sleeve 3a and the small-diameter threaded portion 6, and the expansion piece 16 of the expansion sleeve 3a is slidably expanded to enter the expansion portion 27 of the construction hole 25. Press and fix.

At that time, the shoulder portion 22 of the push-up nut 4 is locked in the push-up nut locking groove 21 provided in the chamfered portion 17 of the expansion piece 16 of the expansion sleeve 3a. It is completely locked and can exhibit a stable tensile strength.
Therefore, the anchor bolt using the expansion sleeve shown in FIG. 5 can be used for construction requiring a greater pulling strength.

  Conventionally, when fixing a heavy object or the like, after placing the heavy object, drilling is performed from above the attachment having a hole, but in the anchor bolt of the present invention, like a conventional anchor bolt, The gap between the protruding bolt and the hole in the attachment is not greatly increased, and the gap between the protruding bolt and the hole in the attachment can be reduced, so that even if a lateral displacement of the attachment occurs, it will be large. It is possible to prevent deviation.

Moreover, since the anchor bolt of this invention does not fall by dead weight even when constructing on a ceiling surface by the function of a fixing member, workability | operativity can be improved greatly.
Further, the anchor bolt of the present invention has a shape that allows the diameter of the fixing member to be reduced, so that the diameter of the pilot hole is slightly larger than the predetermined pilot hole diameter (about 1 mm) due to the influence of the aggregate during drilling. Construction is possible even if it becomes large.

  Moreover, in the anchor bolt of the present invention, since the male screw is formed on the outer peripheral surface over the entire length of the bolt, the adhesive bolt is filled in the gap between the construction hole and the bolt so that the male screw is formed over the entire length of the bolt. Since the adhesive force by the adhesive can be obtained, the tensile strength can be further improved.

Also, with conventional anchor bolts, the position of the enlarged diameter portion provided in the construction hole is defined by the dimensions of the construction hole opening and bottom surface. However, in the anchor bolt of the present invention, since the diameter-enlarged portion of the construction hole is provided after drilling, no trouble occurs even if the hole bottom becomes deeper than the specified depth A by drilling.
Moreover, the specified depth A between the opening of the construction hole and the enlarged diameter portion can be easily and accurately positioned with the aforementioned enlarged diameter drill.

  Furthermore, in the case of the anchor bolt of Patent Document 1, the portion that finally breaks when a tensile force is applied is the shaft portion of the anchor bolt included in the pressing cylinder, but in the case of the anchor bolt of the present invention, Since it becomes the shaft part of a small-diameter bolt, and the construction hole diameter is the same and the tensile strengths of both are comparable, when compared with the anchor bolt of Patent Document 1, the tension by the shape and structure of the anchor bolt of the present invention There is no reduction in strength.

It is a front view which shows the anchor bolt of this invention. It is a front view which shows the anchor bolt main body of this invention. The fixing member which comprises the anchor bolt of this invention is shown, (a) is a top view, (b) is a partial cross section front view. The expansion sleeve which comprises the anchor bolt of this invention is shown, (a) is a fragmentary sectional front view, (b) is a bottom view. The another expansion sleeve which comprises the anchor bolt of this invention is shown, (a) is a fragmentary sectional front view, (b) is a bottom view. It is a partial cross section front view of the raising nut which comprises the anchor bolt of this invention. (A)-(d) is a schematic diagram which shows the construction order of the anchor bolt of this invention. It is a typical fragmentary sectional view which shows the other construction state of the anchor bolt of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Anchor bolt main body 2 Fixing member 3 Expansion sleeve 4 Push-up nut 5 Thick bolt 6 Thin screw part 7 Taper 8 Envelope surface 9 Upper end part 10 of a fixing member Lower end part 11 of a fixing member Stepped wall 12 Hollow part 13 of a fixing member Thin concave portion 14 Side surface 15 of expansion sleeve Slit 16 Expansion piece 17 Chamfered portion 18 Circumferential groove 19 Upper cylindrical body 20 Lower cylindrical body 21 Push-up nut locking groove 22 Push-up nut shoulder 25 Construction hole 26 Expanded diameter Drill 27 Expanded diameter portion 28 of construction hole Rotating shaft 29 (for expanded diameter drill) Slit 30 Projecting blade 31 Receiving base 32 Pressing base 35 Anchor hammer
36 Washer 37 Nut

Claims (7)

An anchor bolt in which a thin screw portion is formed at a lower portion of a large-diameter bolt, a fixing member and an expansion sleeve are loosely fitted to the thin screw portion, and a push-up nut is screwed onto the thin screw portion. The fixing member is formed in a plurality of tapers whose side peripheral surfaces are reduced in diameter downward, and an envelope surface connecting the maximum diameters of these tapers is reduced in diameter downward, and The anchor bolt according to claim 1, wherein a thin thin concave portion is formed on the side peripheral surface in the axial direction. The anchor bolt according to claim 1 or 2, wherein the expansion sleeve has a cylindrical shape, and a plurality of slits extending from one end to the vicinity of the other end in the axial direction are provided on a side peripheral surface. The expansion sleeve has a cylindrical shape and is provided with a circumferential groove in the central portion of the side circumferential surface, and the upper cylinder and the lower cylinder are connected to each other through the circumferential groove. The anchor bolt according to claim 1 or 2, wherein a plurality of slits are provided on the surface in the axial direction. The anchor bolt according to claim 3 or 4, wherein a chamfered portion is formed at the inner peripheral edge of the tip of the expansion piece formed between the plurality of slits of the expansion sleeve. The anchor bolt according to claim 5, wherein a push-up nut locking groove is provided in a chamfered portion formed at a tip inner peripheral edge portion of the extension piece. The anchor bolt according to any one of claims 1 to 6, wherein an upper portion of the push-up nut is formed in a conical shape.

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