JP2000248637A - Anchor plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an anchor plate resolving the problem of tension strength and shearing breakage produced by employing screwing type in place of stud welding because the production of strain due to heat is eliminated when an anchor bar is fixed on a plate body. SOLUTION: An anchor plate comprises a plate body 2 and an anchor bar 3 fixed on one face thereof. In this case, a female screw hole 4 is provided on the plate body 2, a large diameter part 6 is formed on the edge of the shell part of the anchor bar 3, a male screw part 7 screwed in the female screw hole 4 is provided on the outer peripheral face of the large diameter part 6, and the screw bottom diameter D of the male screw part is formed larger than the shell diameter (d) of the anchor bar 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an anchor plate, and more particularly to an anchor plate used for attaching, for example, a seismic isolation rubber bearing to a concrete structure.

[0002]

2. Description of the Related Art A seismic isolation effect is exhibited by being disposed between a lower concrete structure and an upper concrete structure and prolonging the period of seismic motion acting on the lower concrete structure and transmitting it to the upper concrete structure. Rubber bearings are known. This seismic isolation rubber bearing is conventionally attached to these structures in a manner as shown in FIG.

[0003] An anchor plate 13 having a plurality of anchor bars 12 embedded therein is fixed to an upper concrete structure 10 and a lower concrete structure 11. The seismic isolation rubber bearing 14 has upper and lower mounting plates 15, 15, and the upper and lower mounting plates 15, 15 are fixed to the anchor plate 1 by bolts 16.
3 and 13, thus isolating the rubber bearing 14
Are fixed to the upper concrete structure 10 and the lower concrete structure 11, respectively.

In the above-described anchor plate 13, the anchor bar 12 is conventionally fixed to a circular or square plate body 17 by stud welding.
For this reason, the plate body 17 is distorted by the heat of welding and warps, and the flatness of the surface of the rubber bearing 14 in contact with the mounting plate 15 is deteriorated. When the rubber bearing 14 is assembled, a gap is formed in the outer circumferential direction of the contact surface. Occurs. If there is such a gap, the load applied to the rubber bearing 14 will not be evenly distributed, and the durability of the rubber bearing will be reduced.

Conventionally, a stud welding method has been adopted in a state where the outer periphery of a plate body 17 made of a steel plate is restrained on a surface plate so as not to generate distortion due to heat. However, it is difficult to completely prevent the occurrence of distortion, and the distortion is then removed by a press or the like. For this reason, it was troublesome and the cost was high.

[0006] Regardless of the stud welding, the plate body 17
A method is also conceivable in which a screw hole is provided in the hole and the anchor bar 12 is screwed. However, in this case, the anchor bar 12
Has a smaller thread bottom diameter than the body, so that when a horizontal force is applied to the anchor bar, there is a problem that the anchor bottom is liable to shear fracture at the thread bottom.

On the other hand, a stepped cap nut 18 to which a bolt 16 for fixing the seismic isolation rubber bearing 14 is screwed is fixed to the plate body 17 of the anchor plate 13. The cap nut 18 is inserted into a hole provided in the plate body 17 and welded. In this case, the welding position is on the outer peripheral side of the plate body 17 and its welding leg length is small, so that the problem of distortion is not particularly caused. .

[0008]

SUMMARY OF THE INVENTION The present invention has been made on the basis of the above technical background, and has the following objects. SUMMARY OF THE INVENTION An object of the present invention is to provide an anchor plate which employs a screwing method instead of stud welding in order to eliminate distortion due to heat when an anchor bar is fixed to a plate body, but which solves the problem of shear fracture associated therewith. Is to do. Another object of the present invention is to provide an anchor plate capable of accurately and firmly fixing a cap nut by employing a screwing method instead of welding.

[0009]

The present invention employs the following means to achieve the above object. That is, the present invention provides an anchor plate including a plate body and an anchor bar fixed to one surface thereof, wherein a female screw hole is provided in the plate body, and a large diameter portion is provided at a tip of a trunk portion of the anchor bar. Formed on the outer peripheral surface of the large diameter portion, a male screw portion to be screwed into the screw hole, and a screw bottom diameter of the male screw portion is made larger than a body diameter of the anchor bar. On the anchor plate.

Further, the present invention provides a plate body, an anchor bar fixed to one surface of the plate body, and fixed to one surface of the plate body so as to be located on an outer peripheral side of the anchor bar, And a cap nut whose female screw hole is open on the other surface side of the plate body, wherein the first and second caps are respectively provided at positions corresponding to the anchor bar and the cap nut of the plate body.
And a second female screw hole, a large diameter portion is formed at the tip of the trunk portion of the anchor bar, and an external thread portion screwed to the first female screw hole is provided on the outer peripheral surface of the large diameter portion, Increase the thread bottom diameter of the male thread part than the trunk diameter of the anchor bar,
An anchor characterized in that the outer shape of the cap nut is polygonal, a small-diameter portion is formed at the tip, and a male screw portion screwed into the second female screw hole is provided on the outer peripheral surface of the small-diameter portion. On the plate.

[0011] It is preferable that the large diameter portion has a threadless portion having a predetermined length range on the body portion side. In this case, the length of the non-threaded portion is, assuming that the pitch of the screw is p,
It is good to set it in the range of 0.5p to 5p. The anchor plate according to the present invention is applied, for example, for attaching a seismic isolation rubber bearing to a concrete structure, wherein one surface of the plate body is connected to the anchor bar through the anchor bar embedded in the concrete structure. Fixed to the structure,
A seismic isolation rubber bearing is fixed to the other surface of the plate body.

More specifically, the seismic isolation rubber bearing is fixed to the anchor plate via bolts whose upper and lower mounting plates are screwed to cap nuts of the plate body. Therefore, it is preferable that the male screw portion of the cap nut and the female screw hole inside the cap nut have opposite threads. By doing so, when you tighten the bolt,
The cap nut also exerts a force in the direction of tightening the plate body.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional view showing a mounting mode of a seismic isolation rubber bearing to which an anchor plate according to the present invention is applied. The anchor plate 1 has one surface of the plate body 2 fixed to the upper concrete structure 10 and the lower concrete structure 11 via the plurality of anchor bars 3 as in the related art. On the other surface of the plate body 2, a mounting plate 15 of a seismic isolation rubber bearing 14 is fixed by bolts 16, whereby the seismic isolation rubber bearing 14 is fixed to the upper concrete structure 10 and the lower concrete structure 11, respectively. .

The plate body 2 of the anchor plate 1 is
It is made of a circular or square steel plate depending on the shape of the seismic isolation rubber bearing 14. FIG. 2 is an enlarged front view showing an attachment state of the anchor bar 3 to the plate main body 2. A plurality of female screw holes 4 are provided in the plate body 2 at intervals in the circumferential direction, and the anchor bar 3 is screwed into these female screw holes 4.

The anchor bar 3 comprises a body portion 5 and a large-diameter portion 6 formed at the tip thereof. A male thread portion 7 screwed into the female screw hole 4 is formed on the outer peripheral surface of the large-diameter portion 6. ing.
The thread bottom diameter φD of the male screw portion 7 is larger than the diameter φd of the body portion 5. The male screw portion 7 is formed from the tip of the large diameter portion 6, but is not formed over the entire large diameter portion 6, and as a result, the threadless portion 8 remains.

By forming such a threadless portion 8, when the anchor bar 3 is screwed into the plate main body 2, the positioning is reliably performed and the locking is prevented. The length of the threadless portion 8 is desirably about 0.5p to 5p when the pitch of the screw is p.

According to the anchor plate having the above structure, the horizontal force F or the tensile force F ′ is applied to the anchor bar 3.
Works, the screw bottom diameter φD is larger than the body diameter φd of the anchor bar 3, so that no break occurs in this screw portion.

The anchor bar 3 is obtained by forming a large-diameter portion 6 by forging a tip portion of a round steel and then threading the large-diameter portion 6. As shown in FIG. 3, the shape of the head 9 may be a shape having two flat surfaces parallel to each other by cutting out a disk-shaped one, as long as the shape is a spanner, or a hexagonal head. Good. When fastening the anchor bar 3, an adhesive for stopping water may be applied to the male screw portion 7.

A suitable screw diameter (thread bottom diameter φD) with respect to the body diameter φd is as follows. Body diameter φd Suitable screw diameter (screw bottom diameter φD) 13φ M16 (13.8φ) 16φ M20 (17.3φ) 19φ M22 (19.3φ) or M24 (20.8φ) 22φ M27 (23.7φ)

FIGS. 4 and 5 show another embodiment of the present invention. In this embodiment, not only the anchor bar 3 but also the cap nut 30 is fixed to the plate body 2 by screwing. The plate main body 2 is provided with a first female screw hole 4 for the anchor bar 3 and a second female screw hole 31 for the cap nut 30.

The cap nut 30 has a polygonal outer shape (a hexagon in this embodiment), and has a small-diameter portion 32 at its tip by being stepped as in the conventional case.
On the outer periphery of the small diameter portion 32, a male screw portion 33 screwed into the second female screw hole 31 is provided. The cap nut 30 has a female screw hole 34 inside, and the female screw hole 34 is oppositely screwed to the male screw part 33.

The cap nut 30 is fixed to one surface of the plate body 2 by screwing the male screw portion 33 into the second female screw hole 31. In this state, the female screw hole 34 inside the cap nut 30 is It opens on the other surface side of the main body 2.
As a result, the stepped portion 35 of the cap nut 30 is tightened to the plate main body 2, and the cap nut 30 can be accurately and firmly fastened.

The bolt 16 for attaching the seismic isolation rubber bearing 14 to the anchor plate 1 is inserted into a hole 36 provided in the upper and lower attachment plates 15 and screwed into the female screw hole 34 of the cap nut 30. Male thread part 33 of cap nut 30
And the female screw hole 34 are reverse-threaded, so that when the bolt 16 is tightened, a force acts in a direction in which the cap nut 30 is also tightened. Even if the bolt 16 is loosened during maintenance, the cap nut 30 does not rotate because the outer periphery of the cap nut 30 is hardened with concrete. Note that an adhesive may be applied to the male screw portion 33 for stopping water.

According to this embodiment, the plate body 2 can be made as thin as possible because there are no welded portions, and the anchor bar 3 and the cap nut 30 are compact and have good assembling workability. An anchor plate can be obtained.

In the above embodiment, the case where the seismic isolation rubber bearing is attached to the concrete structure using the anchor plate according to the present invention has been exemplified. However, the present invention is not limited to this case. It can also be applied to applications.

[0026]

As described in detail above, according to the present invention, when the anchor bar is fixed to the plate body, no stud welding is employed, so that no distortion occurs in the plate body. Therefore, the plate body only needs to be thick enough to secure the required screw length, and the plate thickness can be made smaller than in the stud welding method, and the cost can be reduced.

Further, since the diameter of the screw bottom is made larger than the diameter of the body portion, no shear breakage occurs at the screw bottom due to the adoption of the screw-in system. Further, by using a screw-in method for the cap nut, the plate body can be made as thin as possible. Further, since the anchor bar and the cap nut are compact and assembly workability is good, a low-cost anchor plate with little distortion can be obtained.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a manner of mounting a seismic isolation rubber bearing to which an anchor plate according to the present invention is applied.

FIG. 2 is an enlarged front view showing an attachment state of an anchor bar to a plate main body.

FIG. 3 is a perspective view illustrating the shape of the head of the anchor bar;

FIG. 4 is a cross-sectional view showing another embodiment.

FIG. 5 is a bottom view of the cap nut.

FIG. 6 is a cross-sectional view showing a manner of mounting a seismic isolation rubber bearing using a conventional anchor plate.

[Explanation of symbols]

 1: Anchor plate 2: Plate body 3: Anchor bar 4: Female screw hole (first female screw hole) 5: Trunk 6: Large diameter part 7: Male screw part 8: No screw part 9: Head 10: Upper concrete structure Object 11: Lower concrete structure 30: Cap nut 31: Second female screw hole 32: Small diameter portion 33: Male screw portion 34: Female screw hole 35: Stepped portion

Claims (6)

[Claims] 1. An anchor plate comprising a plate main body and an anchor bar fixed to one surface thereof, wherein said plate main body is provided with a female screw hole, and a large diameter portion is provided at a tip end of a body of said anchor bar. An anchor, wherein a male screw portion screwed into the female screw hole is provided on an outer peripheral surface of the large diameter portion, and a screw bottom diameter of the male screw portion is larger than a body diameter of the anchor bar. plate. 2. A plate body, an anchor bar fixed to one surface of the plate body, and fixed to one surface of the plate body so as to be located on an outer peripheral side of the anchor bar.
And a cap nut having an internal female screw hole opening on the other surface side of the plate body, wherein the first and the second are respectively located at positions corresponding to the anchor bar and the cap nut of the plate body. 2, a large diameter portion is formed at the tip of the trunk portion of the anchor bar, and a male screw portion screwed into the first female screw hole is provided on the outer peripheral surface of the large diameter portion; The diameter of the screw bottom is larger than the diameter of the body of the anchor bar, the outer shape of the cap nut is polygonal, and a small diameter portion is formed at the tip, and the second female screw is formed on the outer peripheral surface of the small diameter portion. An anchor plate having a male screw portion screwed into a hole. 3. The anchor plate according to claim 2, wherein the male screw portion of the cap nut and the female screw hole inside the cap nut are oppositely threaded. 4. The anchor plate according to claim 1, wherein the large diameter portion of the anchor bar has a threadless portion having a predetermined length range on the body side. . 5. The threadless portion has a thread pitch p
5. The anchor plate according to claim 4, wherein the distance is in the range of 0.5p to 5p. 6. One surface of the plate body is fixed to the structure via the anchor bar embedded in the concrete structure, and a seismic isolation rubber bearing is fixed to the other surface of the plate body. An anchor plate according to any one of claims 1 to 5, characterized in that: