JPH0526217A - Concrete anchor device of footstep - Google Patents

Abstract

PURPOSE:To improve the fitting strength, and prevent deformation and rust in concrete anchor device of a footstep of reinforced concrete structure by forming a male screw in each leg part of a ladder, and screwing a nut, a support sleeve, a fitting sleeve, and a taper plug in order. CONSTITUTION:A steel bar is bent into a U-shape to form a footstep 1 having a step 2 and a pair of leg parts 3. A male screw 5 is formed in the tip of each leg part 3, and a nut 6 and a washer 7 are installed to the base part of the male screw 5. A support sleeve 8 made of steel pipe is installed over the length of nearly 1/2-2/3 of the leg part 3 of the tip side from the washer 7, and furthermore, a fitting sleeve 9 made of steel pipe is installed to the tip of the support sleeve 8. The inner diameter of the support sleeve 8 is formed so as to contact to the thread of the male screw 5, and the outer diameter thereof is formed into a largeness, which can be inserted to a fitting hole 17 of the concrete. A slit 10 is provided in the fitting sleeve 9. A taper plug 11 is provided in the tip of the fitting sleeve 9. Finally, the leg parts 3 are fitted for fixation to the fitting holes 17 of a concrete structure.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an anchor device which is fitted and fixed in a mounting hole formed in a concrete structure so as not to come out of both legs of the trap, and more particularly, after the anchor device is fitted in the mounting hole, a nut is mounted on a concrete surface. The anchor device for a concrete of a trumpet, in which the engaging member expands in response to a very slight pulling of the leg toward the front when tightened tightly, and is fixed by crimping and locking to the concrete surface of the mounting hole. It is a thing.

[0002]

2. Description of the Related Art Conventionally, a ramp is usually installed in a tower or a concrete chimney of a building or a structure made of reinforced concrete or steel frame concrete. To attach both legs of the trap to a concrete structure, mounting holes are usually drilled in advance from the concrete surface. The depth or length of the mounting hole affects the building itself if the reinforcing bar or steel frame embedded as an aggregate is damaged, and therefore the mounting hole must be relatively short so as not to come into contact with it. Even if both legs are inserted and fixed in this short mounting hole, there is a possibility that if the load is lifted or the lift is repeatedly moved up and down and a load is applied, it will sway and slip out (creep).

In view of the above technical situation, the inventor of the present application has proposed an anchor for concrete as described in Japanese Utility Model Publication No. 63-25366. This technology forms a leg anchor of a ramp with a diameter that can be tightly fitted in the mounting hole, and the leg has a taper plug fixedly mounted on the male screw part, the thread cutout part, and the reduced diameter shaft part at the tip, A nut is provided on this leg and the outer circumference of the soft metal anchor sleeve, which is inserted over the entire length of the leg, has approximately the same diameter as the mounting hole over the entire length, and the tapered plug interposition portion is aligned with the plug. It has a tapered hole with a divergent tip, and has a configuration in which a plurality of slits are formed in the axial direction from the tip to the middle.By this, when the nut is tightened on the concrete structure, the taper plug is pulled toward you, The front end side of the sleeve is expanded and fixed to the peripheral surface of the mounting hole by crimping engagement.

[0004]

However, in the prior art as described above, since the taper hole of the expanding sleeve has a long taper portion which is slanted slowly, the tip side is extremely thin. When the nut is screwed, it easily intervenes between the taper plug and the rough surface of the mounting hole, and the taper plug of the leg part corresponds to this and is pulled toward the front side over a long distance. Be done. Therefore, the leg portion has a shorter fitting distance than the relatively short mounting hole. When a load is repeatedly applied to such a ramp, the fitted portion will sway and cause creep.

The anchor sleeve is made of a soft metal material, and when the nut is strongly screwed with a tool such as a wrench to pull the leg part toward you, the base part of the sleeve buckles or contracts to reduce the diameter. It will go into the gap of the shaft and the valley of the male screw. The thin tapered hole not only buckles and contracts, but also deforms like being sharpened by the sharp rough surface of the mounting hole to reduce the locking force, causing the leg anchor to come out early. ..

According to the present invention, a sleeve provided on a leg portion is provided with a support sleeve made of a long steel pipe and a short engagement sleeve made of an alloy steel pipe having a slit at the tip side thereof, and the tip side thereof has a relatively steep angle. By arranging the taper plug of the above, the sleeve can be easily expanded without providing a taper part on the sleeve, and the engagement sleeve can be firmly locked in the mounting hole with an extremely small amount of leg pulling by the nut. The purpose is to maintain the locked state permanently without the pieces deforming or rusting.

[0007]

In order to achieve the above object, in the anchor device of the present invention, a male screw is engraved on both legs of the trap and a nut is screwed, and the diameter of the thread of the male screw is adjusted. From an alloy steel pipe in which a supporting thru made of a steel pipe having substantially the same inner diameter and the same outer diameter as the mounting hole is interposed, and a plurality of wide slits are formed on the distal end side of the sleeve from the distal end edge to the vicinity of the proximal end edge. And a taper plug having a steep angle is fixed to the tip of the leg portion on the tip side of the sleeve for engagement.

[0008]

In order to mount the anchor device constructed as described above, first, a pair of mounting holes having substantially the same diameter as the diameter of the sleeve are drilled from a predetermined position on one side of the concrete. Then, the two leg anchor devices of the trap are tightly fitted into the mounting holes. Then, when the nut and washer at the preset position reach the position where they contact the concrete surface,
The nut is tightened to pull the leg part very slightly toward the front side, and at this time, the taper plug penetrates into the inner peripheral surface of the engagement sleeve. Corresponding to this, the distal end side of each piece of the engaging sleeve cut out by the slit expands outwardly of the leg shaft radius. Since this expansion force is almost in contact with the inner peripheral surface of the mounting hole from the beginning, at the same time when the expansion starts, the concrete rough surface is crushed by strong pressing force from the sleeve tip side made of hard steel material. Engage with. Then, a slight connection portion on the base end side of the engagement sleeve cut out by the slit is deformed when expanded, but does not break due to the toughness made of alloy steel material, and each piece bent in the circumferential direction. The shape of does not deform and engages the inner peripheral surface of the mounting hole with a strong pressing force. Further, because of the rustproof property, the locked state is permanently maintained, so that it does not come out carelessly.

[0009]

EXAMPLES Examples will be described with reference to the drawings. In FIG. 1, a turret 1 is formed by bending a steel rod in a U shape to form a step 2 and a pair of legs 3 bent at right angles from both ends of the step 2. The tip side of the leg portion 3 constitutes the anchor device 4 according to the present invention. This trump 1 is to attach a required number of pieces to a concrete structure at equal intervals.

As shown in FIG. 2, a male screw portion 5 is engraved on the distal end side of the leg portion 3 over a predetermined length from the distal end. A nut 6 is screwed onto the base of the male screw portion 5 and a washer 7 is interposed. A support sleeve 8 is interposed over a length of about ½ to ⅔ of the leg portion on the tip side of the washer 7. The support sleeve is made of a drawn steel pipe, the inner diameter of which is rotatably in contact with the crest portion of the male screw portion, and the outer diameter of which is a diameter that allows slidable close fitting in the mounting hole 17.

The engagement sleeve 9 interposed so as to contact the tip of the support sleeve 8 is 1/2 to 1/3 of the support sleeve 8.
The length of the support sleeve 8
It has the same diameter as. The engagement sleeve 9 is made of an alloy made of an iron material mixed with chrome, nickel, or manganese, or a pipe made of an alloy steel material such as hard stainless steel material. The engagement sleeve 9 is axially equidistant from the leading edge to the vicinity of the proximal edge. A plurality of slits 10 are cut out. Further, the corners of the outer peripheral corners of the base end face are chamfered so that the expanding action is facilitated, and the corners of the inner peripheral corner of the front end face are chamfered so that the taper plug 11 can easily enter during the expansion. It is a thing.

The taper plug 11 provided at the tip of the leg portion 3 is made of steel and has a female thread 12 formed in the shaft hole so as to be screwed into the male screw 5 of the leg portion, and is steeply inclined toward the engagement sleeve side. The tapered portion 13 is formed. Further, the leg portion 3 and the taper plug are provided with radial screw holes 14 and 15 and are fixed to the leg portion so as not to rotate by driving a screw 16.

[0013]

[Effect] Since the present invention is configured as described above, the following effects are exhibited. The sleeve is divided into the engagement sleeve and the support sleeve, and the long support sleeve has a hard drawn and drawn steel pipe that is not deformed tightly fitted into the concrete mounting hole.Therefore, even if repeated load is applied to the step, the mounting hole and the supporting sleeve are There are no gaps and no shaking defects.

Further, the engaging sleeve is provided with a slit having a relatively wide width from the front edge to the vicinity of the base end, and the plurality of engaging pieces formed by being divided by the slit are hard to be deformed because of the alloy rigid material. Immediately and strongly engage the nut so that the tip end bites into the mounting hole while maintaining its shape by tightening the nut. The connecting portion of the engaging piece at the proximal end of the slit is formed to be thin, but it has toughness and is easily deformed and expanded when the taper block enters.

Further, since the taper block is formed in a taper shape with a steep angle, even if the amount of pulling of the front side of the leg portion due to the tightening of the nut is extremely small, the tip of the engaging sleeve is greatly expanded and completely attached. Not only does the anchor device engage with the hole to lock the anchor device in the mounting hole, but since it is a non-rusting alloy steel material, it has the effect of maintaining a permanently strong locked state.

[Brief description of drawings]

FIG. 1 is an overall perspective view in which an anchor device is provided on a leg portion of a trap.

FIG. 2 is a partially cutaway side view showing a state in which an anchor device provided on a leg portion of a trap is tightly fitted in a mounting hole of concrete.

FIG. 3 is a partially cutaway side view showing a state in which the second anchor device is locked and fixed in a mounting hole. 1 Talap equipped with an anchor device 2 Step 3 Leg part 4 Aner device 5 Male screw of leg part 6 Nut 8 Support sleeve 9 Engaging sleeve 10 Slit 11 Taper plug 17 Concrete mounting hole

Claims (1)

Claims: What is claimed is: 1. An anchor device provided on both leg portions of a ramp that slidably fits into a pair of mounting holes drilled in a reinforcing bar or a steel-framed concrete structure. A male thread is engraved on the male thread, a nut is screwed on the proximal end of the male thread, and a washer is interposed, and then a steel pipe with a 1/2 to 2/3 length of the leg section with the male thread is used. A support sleeve having a diameter approximately the same as that of the mounting hole and an outer diameter approximately the same as that of the mounting hole is interposed. A short engagement sleeve having the same diameter as the sleeve is interposed, and then a tape plug inclined from the tip of the leg to the tip of the engagement sleeve at a steep angle is screwed and fixed to the engagement sleeve side. Anchor device for concrete of tarup.