JPS5856268Y2 - Rebar joint fittings - Google Patents

Description

[Detailed explanation of the idea] The present invention relates to a reinforcing bar joint.

Generally, in the construction of reinforced concrete buildings, joints of reinforcing bars need to have strength to resist external forces such as tensile and bending in order to maintain the integrity of the reinforcing bars.

BACKGROUND ART Conventionally, for connecting reinforcing bars to each other, a joining fitting has been proposed that includes a plurality of strips surrounding a joint of reinforcing bars and a pair of ring-shaped members fitted to the strips.

According to this joint fitting, the strip is configured such that the thickness gradually decreases from the center portion to both ends thereof,
By moving the ring-shaped member from both ends of the strip toward its center, the reinforcing bars are tightened and joined together.

By the way, reinforcing bars and strips generally have dimensional errors during manufacturing or processing.

For example, there may be a manufacturing error in the diameter of the reinforcing bars that causes a step when the reinforcing bars are butted against each other, or there may be a manufacturing error in the diameter of the central portion of the strip.

In such a case, there is a problem in that when reinforcing bars are joined using the joining fittings, a large pull-out resistance cannot be obtained.

This is because the central part of the strip is thicker than both ends, so the central part located at or near the end of the reinforcing bar has the least flexibility in deflection, and conversely, the central part of the reinforcing bar has the least bending deformability. The ends located farthest from each other have the greatest flexibility in bending and deformation, and as a result, the central part of the strip conforms to the reinforcing bars on both sides, creating a strong bond between the central part of the strip and both reinforcing bars. This is because contact cannot be obtained or a gap is created between the center of the strip and the reinforcing bar, making it impossible to securely tighten the bar. It can be easily removed from the gap.

Therefore, an object of the present invention is to provide a joining metal fitting that can obtain a large pullout resistance even if there is a dimensional error in the reinforcing bar or the above-mentioned piece.

The reinforcing bar joint fitting according to the present invention is characterized in that the strip is configured so that the strip increases gradually from the center toward both ends, so that the strip has the greatest flexibility in bending and deformation at the center. When moving a pair of ring-shaped members fitted to multiple strips toward the ends of the strips, the strips blend well with the reinforcing bars near the ends of the reinforcing bars and can come into close contact with them, causing the reinforcing bars to Securely tightened onto the strip.

The features of the invention will become more apparent from the following description of the illustrated embodiment.

As shown in FIGS. 1 and 2, the reinforcing bar joint fitting 10 according to the present invention comprises a pair of reinforcing bars 12 arranged as reinforcing materials for a concrete structure and made of a pair of round steel whose ends 11 are butted against each other. placed at the junction of the

The reinforcing bar joint fitting 10 is made up of a plurality of strips 16 arranged around and in contact with the joint portion of the reinforcing bars 12, and a pair of ring-shaped members 18 fitted to the strips.

Each strip 16 is made of a metal material whose wall thickness gradually increases from its center portion 16a toward both ends 16b, and the curvature of its inner circumferential surface 20 is approximately equal to the curvature of the outer circumferential surface 12a of the reinforcing bar 12. , has an arcuate cross-sectional shape as a whole.

By configuring the strip 16 in this way, both ends 16
It becomes easier to bend as it moves from b to the center part 16a,
Central part 1 located at or near the end 11 of the reinforcing bar 12
6a is the most easily deformed.

The nongangular member 18 is made of a metallic material, and as shown in FIG. gradually increases, and the inclination angle of the inner circumferential surface 24 of the ring-shaped member 18 in the axial direction of the reinforcing bar 12 is approximately equal to the inclination angle of the outer circumferential surface 22 of the strip 16.

The radius of curvature of the inner peripheral surface 24 of the ring-shaped member 18 is
a, the radius of curvature of the outer circumferential surface 22 at the central portion 16a of the strip 16 is greater than the radius of curvature of the strip 16 at the other end 18b.
The radius of curvature is smaller than the radius of curvature of the outer circumferential surface 22 of both ends 16b of 6.

When using the reinforcing bar joint fitting 10, the pair of ring-shaped members 18 are moved toward the center portion 16a of the strip 16 in advance, and a plurality of strips 16 are placed around and around the reinforcing bar at the joint of the reinforcing bar 12. The ring-shaped member 18 is arranged at intervals in the circumferential direction so as to be in contact with each other, and then one end 18a of the ring-shaped member 18 is attached to the strip 1.
6 towards the end 16 b side (direction shown by the arrow in the figure),
For example, the strip 16 is held at the disposed position by moving the ring-shaped member 18 by tapping lightly with a hammer, and further moved toward the end 16b of the strip 16 using a jack or the like.

When the ring-shaped member 18 is moved toward the end 16b of the strip 16, that is, in the direction in which the wall thickness gradually increases, the highly deformable thin center portion 16a is in a state where it fits well with the end 11 of the reinforcing bar. The strip 16 is in close contact with the reinforcing bar 12.
2, and thus the pair of reinforcing bars 12
is securely fastened to the strip 16.

Therefore, even if there is some dimensional error in the reinforcing bars 12 or the strips 16, when an external force such as a tensile force is applied to the reinforcing bars 12, the frictional force acting between the reinforcing bars 12 and the strips 16 will resist the external force. A strong connection between the reinforcing bars 12 is maintained.

The amount of movement of the ring-shaped member 18 is determined by the amount of movement of the ring-shaped member 18.
The reinforcing bar 1 is selected as appropriate depending on the inclination angle of 2.
In order to more reliably apply the clamping force to 2, it is desirable to move the ring-shaped member 18 over the strip 16 until it yields.

The above-mentioned example relates to a case where the joining fitting 10 of the present invention is applied to joining round steel, but it can be similarly applied to joining deformed steel bars.

Furthermore, the outer peripheral surface 22 of the strip 16 and the ring-shaped member 18
The inner circumferential surface 24 may be defined as a plane instead of the illustrated example.

According to the reinforcing bar joint according to the present invention, since the thickness of the strip gradually increases from the center to both ends,
The thin central portion, which is most easily deformed, is located around or near the ends of the pair of reinforcing bars to be joined.

Therefore, there may be manufacturing errors in the diameter dimensions of a pair of reinforcing bars, slight deformation at the ends of the reinforcing bars due to trimming of the reinforcing bars, or manufacturing errors in the center of the strip. However, the strip fits well with the reinforcing bars in its center, and both reinforcing bars can be tightened securely.
Thereby, it is possible to obtain a large pull-out resistance.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a reinforcing bar joint according to the present invention, and FIG. 2 is a partial vertical sectional view of the reinforcing bar joining fitting. 10: Rebar joint fitting, 11: End of rebar, 12: Rebar,
16: Strip, 16a: Center portion of strip, 16b: End portion of strip, 18: Ring-shaped member.

Claims (1)

[Scope of utility model registration request] A plurality of strips, the thickness of which gradually increases from the center to both ends, are arranged surrounding the reinforcing bars and in contact with the reinforcing bars at the joints of the reinforcing bars, and the strips are fitted into the strips and have the shape described above. and a pair of ring-shaped members that can tighten the shaped piece from the periphery by moving it toward both ends of the reinforcing bar joint.