JPS595219Y2 - anchor bolt - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an anchor bolt for use in concrete, etc.

A typical conventional anchor bolt is described in Japanese Patent No. 96968.

Referring to FIGS. 10 to 14 of the above-mentioned publication, a cylindrical body is provided with inclined surfaces on the inside of both ends, and two sets of dead-end elongated holes are formed inward from both ends of the cylindrical body, and at both ends of the cylindrical body. One is a conical nut, and the other is a conical plug without threads, both of which are molded together through a broken part called a runner, and a bolt is screwed into the conical nut, and the broken part is removed by rotating the bolt. After cutting, a conical nut is inserted into the cylindrical body to expand the cylindrical body, and at the same time, the other conical plug is also thrust into the cylindrical body to expand both ends of the cylindrical body and then installed in concrete.

In the conventional type described above, the elongated hole is provided in the middle of the cylindrical body, so that the cylindrical body is held in a constricted shape at the center by conical nuts and conical plugs attached to both ends within the concrete hole.

By the way, since the anchor bolt is for supporting the load in the axial direction, if the center part is constricted, about half of the cylindrical body does not do anything to increase the supporting force of the bolt.

In the above cited example, in the state shown in Figure 14, the diameter of the cylindrical body is also large at the opening where the conical plug is attached, but the bolt is supported only by the conical nut at the tip. It is.

The biggest drawback of conventional anchor bolts is that the stress distribution is concentrated at the tip of the cylindrical body.

In this case, if a load beyond the allowable limit is applied, the anchor bolt may break the surrounding concrete, and the anchor may come off with the concrete.Ideally, the stress distribution generated in the cylindrical body should be gentle from the base force toward the tip. It is separated in a curved manner.

This is not only because the diameter of the cylindrical body is increased, but also because the diameter of the cylindrical body is expanded before it is charged into the concrete hole. As a result, the entire surface of the cylindrical body from the base to the tip is crimped.

By satisfying the above requirements, it is possible to obtain an anchor bolt that can support a larger load than conventional anchor bolts even if a bolt with the same diameter as its cousin is used.

The applicant of the present application filed Utility Model Application No. 79013/1983 in order to eliminate these conventional drawbacks.

The above-mentioned device forms a thin wall part in the middle of the sleeve and provides two slits extending from the open end to the thin wall part, screws onto a bolt at the tip of the sleeve, attaches a cone nut, and rotates the bolt to attach the cone nut. After pulling up and expanding the tip of the sleeve, pull up the part along with the cone nut to break the thin part, and divide the part from the thin part of the sleeve to the tip into two, and the divided sleeve member is larger than before installation. This anchor bolt has a diameter that increases from the base to the tip, and the entire sleeve is held in the concrete hole.The sleeve is crimped and supported in the concrete hole so that the stress distribution on the sleeve is not concentrated at the tip. was firmly crimped along its entire length, successfully increasing its supporting capacity.

In the above device, the thin walled part of the sleeve is broken by the force of pulling up the cone nut, and the divided snows are polymerized on the outside of the base of the sleeve. However, when the cone nut is started to be pulled up, the tip of the sleeve expands and the concrete is removed. Because the sleeve was connected to the hole and pulled up while connected, it was sometimes difficult to move the sleeve.

The present invention is a further improvement of the previously proposed device, and when the tip of the sleeve is expanded by pulling up the cone nut, that is, when the tip of the sleeve is bonded to the concrete hole with a certain amount of pressure, the base of the sleeve is By pressing toward the sleeve to break the thin-walled part of the sleeve and pushing the sleeve base into the inside of the divided sleeve, the sleeve is reliably divided, and when the sleeve is divided, the sleeve is divided from the base to the tip. The purpose of this invention is to provide an anchor bolt that can be crimped into a concrete hole with a large diameter slope.

For this reason, the anchor bolt of the present invention has a thin-walled part in the middle of the sleeve, one of which is a cone member, and the other part of which is a crimp sleeve.
A slit is provided and a cone nut screwed onto the bolt is attached to the tip of the sleeve, and when inserting the anchor bolt into the concrete hole, the end of the sleeve and the tightening nut screwed onto the bolt for pulling up the cone nut are connected. In between, a supporter having a thickness corresponding to the overlapping length of the crimp sleeve to be divided and the cone member inserted into the crimp sleeve is attached to limit the insertion depth of the anchor bolt, and the cone nut is pulled up to remove the tip of the crimp sleeve. After expanding and joining the concrete hole with a certain amount of pressure, the supporter is removed and the sleeve is pressed with a force that pulls up the cone nut,
The thin wall part of the sleeve is broken, and when inserting an anchor bolt into a concrete hole, the sleeve is not inserted completely, but the thickness of the supporter is made to protrude from the concrete wall, and the crimp sleeve is supported by a predetermined pressure. It is characterized in that the sleeve is sometimes pressed to ensure division of the crimping snub.

Next, embodiments of the present invention will be described with reference to the drawings.

Reference numeral 1 denotes a sleeve, with a thin wall portion 2 provided in the middle, one end forming a cone member 3, and the other end forming a crimp sleeve 4.

The thin portion 2 is formed by dividing the inside of the sleeve by an outer circumferential cut groove 21 and an inner circumferential cut groove 22, and a portion including the outer circumferential cut groove 21 is formed in the cone member 3.

In the thin portion 2, the direction in which the cut line of the outer peripheral cut groove 21 extends is
If the inner circumferential cut groove 22 is located inside the direction in which the cut line extends, the cone member 3 and the crimp sleeve 4 will be reliably separated when an axial load is applied to the sleeve 1, as will be described later. be done.

For this reason, the outer circumferential surface of the thin-walled part where the inner and outer circumferential surfaces of the sleeve are tapered is such that the outer diameter of the sleeve increases as the distance from the thin-walled part increases, and the inner circumferential surface of the sleeve decreases as the distance from the thin-walled part increases. They are each formed on a slope.

The tip opening of the crimp sleeve 4 forms a tapered portion 5 that becomes larger in diameter toward the opening end, and two slits 6.6 parallel to the axial direction are inserted into the thin wall portion 2 from the opening end. It is provided up to the boundary line of the outer peripheral cut grooves 21 and 22.

Further, the surface of the crimp sleeve 4 is knurled.
Alternatively, irregularities are formed in a shape that increases the frictional force between the prepared hole C and the concrete.

An annular indicator groove 7 is formed at the open end of the cone member 3 to serve as a guide for protruding the sleeve 1 from the concrete hole when inserting the sleeve 1 into the concrete hole.

A stud bolt 8 is inserted into the sleeve 1, and a cone nut 9 is tightened at the open end of the crimp sleeve 4, and a hexagonal nut 11 is tightened at the end of the cone member 3 via a washer 10.

12 is a retaining groove provided on the end face of the stud bolt 8 on the side where the hexagonal nut 11 is mounted.

A supporter 13 is installed between the concrete wall surface on which the anchor bolt is attached and the washer 10 of the stud bolt, and has a thickness corresponding to the overlapping length of the crimp sleeve to be divided and the cone member inserted into the crimp sleeve. , the tip of the crimp sleeve 4 is expanded by pulling up the cone nut 9, and when it is joined to the concrete hole with a certain amount of pressure, it is removed.

The supporter 13 is formed into a bifurcated shape, and allows the sleeve to be inserted and removed from the lateral direction freely.

In order to attach the attachment B to the concrete wall A using the anchor bolt configured as described above, a pilot hole C having approximately the same diameter as the outer diameter of the sleeve 1 is bored at a predetermined position on the wall A.
An anchor bolt is inserted into this pilot hole C, and the sleeve 1 is inserted using the indicator groove 7 provided at the end of the sleeve as a guide.

Next, a metal fitting such as a screwdriver is inserted into the engagement hole 12 formed at the end of the stud bolt 8 to prevent the sleeve 1 from rotating, and the hexagonal nut 11 is rotated to pull up the cone nut 9.

When the cone nut 9 begins to move within the crimp sleeve 4, the crimp sleeve 4 begins to expand from its open end, and the torque for engaging the lower hole C and pulling up the cone nut 8 increases.

After the stud bolt 8 and the hexagonal nut 11 no longer rotate together and are further tightened appropriately, that is, when the rotational torque of the stud bolt reaches a predetermined value, the supporter 1
3 and rotate the hexagonal nut 11 again.

The crimp sleeve 4 has already been expanded from the tip by the cone nut 9 and fixed in the pilot hole C with a certain degree of pressure, so when the hexagonal nut 11 is rotated, the cone member 3 moves toward the crimp sleeve 4. The thin walled portion 2 is ruptured by the pressure of the cone member 3 towards the crimp sleeve 4 .

The crimp sleeve 4 is pulled up by the cone nut 9 and the cone member 3 is pressed toward the crimp sleeve, so that the total pressure causes the crimp sleeve 4 to
The cone member 3 is divided into two thin plates, and the tip portion is superimposed on the outside of the cone member 3.

After fixing the cone nut 9, temporarily tighten the hexagonal nut 1.
1 and the flat washer 10 are removed, the stud bolt 8 is inserted into a hole previously drilled in the fixture B, and the hexagonal nut 10 is tightened again through the flat washer 10 to attach the fixture B to the concrete wall surface A.

Figures 5a and 5b show spacers 14 and 15, and when a longer bolt is required due to the thickness of the object to be attached or the purpose of use of the anchor bolt, these spacers 14 and 15 can be used as sleeves 1. It is installed between the washer 10 and the washer 10.

In this case as well, the indicator groove 7 can be used as a guide for inserting into the prepared hole C.

In the embodiment, a stud bolt into which a hexagonal nut is screwed is used, but instead of the stud bolt, a bolt having a normal hexagonal head may be used.

As explained above, in the present invention, the sleeve is formed into a cone member and a crimp sleeve through a thin wall part, a cone nut screwed onto a bolt is attached to the tip of the crimp sleeve, and an anchor bolt is inserted into a concrete hole. In this case, a supporter to limit the insertion depth is attached between the end of the sleeve and a tightening nut screwed onto the bolt for pulling up the cone nut. Just by inserting the cone member, the insertion length into the crimp sleeve is secured, and after expanding the crimp sleeve by moving the cone nut, the cone member is moved toward the crimp sleeve to break the thin portion, At the same time, the cone member of the sleeve protrudes into the inside of the two-split cone member to reliably press and support the cone nut in the concrete hole.

Moreover, the trough-shaped crimping sleeve is divided into two halves and expands in an inclined manner from the base of the sleeve to the tip, and the entire surface of the sleeve is crimped and supported in the concrete hole, so the stress distribution of the load applied to the sleeve is Since the cone nut is distributed in a gentle curve toward the tip, the supporting force is enhanced and the cone nut has an even stronger retaining action, resulting in a more reliable anchor bolt with stronger supporting force than conventional anchors. effective.

[Brief explanation of drawings]

Figure 1 is a perspective view of the entire anchor bolt of the present invention assembled, Figure 2 is a partially cutaway side view of the anchor bolt before it is inserted into a concrete hole and fixed, and Figure 3 is a partially cutaway side view. The figure is a cross-sectional view showing the attachment after the anchor bolt has been fixed, Figure 4 is a side view with a part of the sleeve cut away, and Figures 5a and 5b are side views with a part of the spacer cut away. FIG. 6 is a perspective view of the supporter. 1...Sleeve, 2...Thin wall part, 3.
・Curved cone member, 4...Crimp sleeve, 5...
Curved taper section, 6...Slit, 7...
Indication groove, 8... Stud bolt, 9...
- Cone nut, 10... Bent washer, 11 - Hex nut, 12... Engagement groove, 13... Supporter.

Claims (1)

[Scope of utility model registration request] The inner and outer circumferential surfaces of the sleeve are cut in an inclined manner in the middle of the sleeve, the outer circumferential cut groove becomes smaller in diameter toward the center of the sleeve, and the inner circumferential cut groove is cut parallel to the outer circumferential cut groove. The sleeve is partitioned into a cone member in a portion including the outer circumferential cut groove and a crimp sleeve in a portion including the inner circumferential cut groove, and the tip opening of the crimp sleeve is tapered to have a larger diameter toward the open end. In addition, two slits are provided parallel to the axial direction from the tip opening end to the thin-walled portion, and a bolt is inserted into the sleeve from the cone member, and a bolt is inserted into the portion protruding from the tip opening of the crimp sleeve. When screwing a cone nut and inserting an anchor bolt into a prepared hole in concrete, etc., a crimp sleeve is separated between the end of the sleeve and a tightening nut screwed onto a bolt that pulls up the cone nut. An anchor bolt equipped with a supporter that has a thickness corresponding to the overlapping length of the cone member to be inserted and limits the insertion depth of the anchor bolt.