JPS6018497Y2 - Deformed steel bar joints for concrete reinforcement - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to the improvement of a joint for deformed steel bars for reinforcing concrete that can be easily implemented on site.

Conventionally, so-called steel bars such as deformed reinforcing bars for concrete reinforcement and PC steel bars used in the civil engineering and construction fields have been increasingly made larger in diameter and prefabricated. It is a successor.

A well-known general method of joining is to butt deformed steel bars together, cover that part with a designated iron pipe, and crush it.
A crimp joint that is inserted into the recess between the edges of a steel bar and transmits stress through the iron pipe, and a nut or coupler that forms a thread on the entire circumference of the steel bar or the curved edge of the steel bar, and is screwed into the thread. There are various types of threaded joints that aim to transmit stress.

However, with the above-mentioned known crimp joints, as the diameter of the steel bar increases, the device becomes larger and heavier, making it unsuitable for on-site workability.

In addition, in threaded joints, especially joints with threaded reinforcing bars in which the threads are formed by hot rolling on the protrusions on the surface of the steel bar, some backlash that occurs between the threads on the steel bar side and the threads of the nut or coupler can be avoided. First, if tensile force is applied to this joint in concrete, all of this tensile force will be applied to the cross section of the concrete until the gap between the screw threads disappears, and even a small tensile force can cause cracks in the concrete. be.

The present invention took into consideration the above-mentioned problems, and has particularly excellent features in terms of on-site workability, concrete adhesion of the joint sleeve, connectivity with the base steel bar, stress transmission, product manufacturing cost, and productivity. a ridge for adhesion to concrete, which has an adhesion force on the outer peripheral surface at least equal to or greater than the adhesion force to concrete of deformed reinforcing bars;
and a two-part separate layer coupler, which has a spiral groove threaded between the ridges to surround each other in a spiral manner, and a fitting groove that fits the protrusion of the deformed reinforcing bar to be connected on the inner circumferential surface. and a spring that is elastically tightened from the periphery so as to be screwed into and surrounding the spiral groove of the coupler.

Embodiments of the present invention will be described below with reference to the drawings.

In the figure, reference numeral 1 denotes a two-part separate layer coupler cast from a metal material with suitable strength, and the outer surface of the separate layer coupler 1 is spirally arranged along its axial direction with respect to the axis of the separate layer coupler 1. A continuous spiral groove 2 is provided, and when each side layer coupler 1 is placed in a symmetrical position as shown in the figure, the spring 3 is spirally advanced by the screw lead of the spiral groove 2, and the spring 3 is elastic. This allows the side layer coupler 1 to be elastically tightened from the periphery so as to surround it.

Reference numeral 4 denotes a concrete adhesion protrusion formed on the outer circumferential surface of the side layer sleeve 1 at a portion partitioned between the spiral grooves 2. The helical groove 2 threads between the protrusions 4 in a spiral pattern. This concrete adhesion protrusion 4
are formed to have concrete adhesion strength equal to or greater than that of general deformed reinforcing bars.

When the spring 3 is screwed into the spiral groove 2, the concrete adhesion protrusion 4 prevents the split coupler 1 from pressing or pulling the spring 3 in the axial direction of the split coupler 1.
It also plays the role of ensuring that you do not slip away.

In other words, the spring 3 is prevented from coming off the outer peripheral surface of the split coupler 1 due to vibrations or external forces during concrete pouring, or other external forces.

The concrete adhesion protrusions 4 are shown as continuous twill-like protrusions defined by the spiral grooves 2 in the figure, but in short, they have the same purpose as protrusions of general deformed reinforcing bars, which is to increase concrete adhesion. Since this is to prevent the spring 3 from coming off from the split coupler 1, it does not necessarily have to be continuous. The same effect can be obtained even if they are distributed and protruded in a shape.

Reference numeral 5 denotes a groove for fitting a protrusion (frame) of the base material reinforcing bar to be joined, which is provided on the inner peripheral surface of the split concrete 1, and has a shape and arrangement that allows it to receive and fit the protrusion 7 of the general deformed reinforcing bar 6 to be joined. They are formed on the inner peripheral surface of the split coupler 1 at predetermined intervals along the line direction.

Since the joint according to the present invention has the above-mentioned structure, when it is put into practice, as shown in the figure, the base material reinforcing bars 6, 6, which are held so as to be surrounded from the left and right by the coupler 1, are connected to the coupler 1. It can be strongly combined with

At this time, the feature of the present invention is that all of the protrusions 7 of the base material reinforcing bars 6, 6 are fitted into the fitting groove 5 of the coupler 1, and tightly joined by the clamping force from the periphery of the spring 3 in the axial direction. In particular, by the action of the spring 3, the coupler 1 is able to forcibly tighten the deformed reinforcing bars 6, 6 to be connected from the left and right sides.

Moreover, at this time, the concrete adhesion protrusion 4 can prevent the spring 3 from being pulled out or displaced from the split coupler 1.

That is, when the spring 3 is screwed into the spiral groove 2, since the spiral groove 2 is formed between the concrete adhesion protrusions 4, the protrusions 4 are raised higher than the spring 3. Since the spring 3 does not move even if it is pressed or pulled in the axial direction of the split coupler 1, the spring 3 may come off or become misaligned from the split coupler 1 due to vibrations during concrete pouring, external forces, etc. There is no.

Therefore, according to the joint of the present invention, it is possible to connect the base metal reinforcing bars with a very simple operation.In particular, since the coupler is a two-part, separate layer type, it is possible to use a spanner or wrench for dense reinforcement. It is effective in places where tools such as the The tension (axial force) is also very good, and since the spring is formed so that it will not come off or slip off from the outer circumferential surface of the coupler, structures constructed by pouring concrete will be able to withstand it. Since there is no local strength deficiency caused by detachment or loosening, it is extremely strong in terms of strength, contrary to the fact that products that can be connected continuously with extremely simple operations tend to lack strength. It is something that

As explained above, the joint of the present invention can be expected to have extremely excellent effects as a continuous connection member for individual base material reinforcing bars, and is especially suitable as a joint for general deformed reinforcing bars.
In its use, stable joint performance can be obtained without requiring special skills, and it also has excellent properties in terms of workability, concrete adhesion, breaking strength, etc.

[Brief explanation of drawings]

The drawing is a sectional view of a main part of an embodiment of the present invention in a state of implementation. 1...Split coupler, 2...Spiral groove,
3...Spring, 4...Concrete adhesion protrusion, 5...Fitting groove.

Claims (1)

[Scope of utility model registration request] Forming on the outer peripheral surface a ridge for concrete adhesion having an adhesion force at least equal to or greater than the concrete adhesion force of the deformed reinforcing bars, and a spiral groove surrounding the ridges in a spiral manner, In addition, there is a two-part separate layer coupler with a fitting groove formed on the inner circumferential surface that fits the protrusion of the deformed reinforcing bar to be connected, and a coupler elastically attached from the periphery so as to screw into and surround the spiral groove of this coupler. A deformed steel bar joint for concrete reinforcement, characterized by comprising a tightening spring.