KR102076597B1 - Rebar coupler and method for manufacturing thereof - Google Patents

Abstract

The present invention relates to a rebar coupler and a manufacturing method thereof. According to the present invention, the rebar coupler comprises: a first coupler housing and a second coupler housing which respectively have fastening holes on the entrances for inserting a rebar and on the opposite side of the entrance; a plurality of first lock pins installed in the first coupler housing and a plurality of second lock pins installed in the second coupler housing; fastening members which fasten and connect the first coupler housing and the second coupler housing; and a first spring, wherein one end is supported by the fastening members, and the other end applies an elastic force to the plurality of first lock pins, and a second spring, wherein one end is supported by the fastening members and the other end applies an elastic force to the plurality of second lock pins on the opposite side of the fastening members. A plurality of first guide bumps are formed on the first coupler housing to allow the plurality of first lock pins to be located by being apart at regular intervals on the inside of the first coupler housing. In addition, a plurality of second guide bumps can be formed on the second coupler housing to allow the second lock pins to be located by being apart at regular intervals on the inside of the second coupler housing. The present invention aims to provide a rebar coupler and the manufacturing method thereof, capable of forming a shape to bind the lock pins on the coupler body at once, while improving the fastening force of the coupler.

Description

Rebar coupler and its manufacturing method {REBAR COUPLER AND METHOD FOR MANUFACTURING THEREOF}

The present invention relates to a rebar coupler and a method for manufacturing the same.

Concrete is very resistant to compression, but weak to tensile. The tensile strength of concrete is very small, from 1/9 to 1/13 of the compressive strength. Reinforcing bars, on the other hand, withstand both tension and compression. When reinforced concrete is reinforced with reinforced concrete, the strength of concrete that is very resistant to compression can be utilized, and the resistance to tensile and shear, which is a weak point, can be reinforced with reinforced concrete.

Since the coefficient of thermal expansion of reinforcing bars and concrete is almost the same, and the reinforcing bars in concrete are not corroded, the combination of concrete and reinforcing bars is an excellent composite material if only the adhesion strength of reinforcing bars to concrete is maintained.

The joints of reinforcing bars are standardized to increase the length of reinforcing bars produced in factories by connecting them at the construction site as necessary. At this time, since the tensile force or the compressive force is transmitted through the joint, the quality of the joint is very important. As the joint method of reinforcing bars, overlap joints connecting to the binding line are common, but there are also methods such as welding joints, screw joints, and sleeve crimping joints.

The reinforcing work of reinforcing bars at the construction site can affect the construction period depending on the time and convenience of the work. The quick coupler appeared for the convenience and speed of the joint work of reinforcing bars. When the quick coupler enters the butt reinforcing bar into the sleeve, the lock pins in the sleeve fix the bars of the reinforcing bar to prevent the reinforcing bar from disengaging from the sleeve. Various shapes of the quick coupler have been proposed, and there are various manufacturing methods accordingly. However, the existing quick coupler has a problem that there are many parts required, the manufacturing method for this is complicated, and the cost increases.

* Related prior art

Korean Registered Patent No. 10-0989783 (registered on October 18, 2010)

Japanese Patent Publication No. 1998-018510 (published on January 20, 1998)

An object of the present invention is to provide a reinforcing bar coupler and a method of manufacturing the same, which can improve the fastening force of the coupler while simultaneously forming a shape in which the lock pins can be restrained on the coupler body.

Reinforcing bar couplers related to the present invention, the first coupler housing and the second coupler housing having an inlet for inserting the reinforcing bar and a fastening hole on the opposite side of the inlet, respectively; A plurality of first lock pins installed on the first coupler housing and a plurality of second lock pins installed on the second coupler housing; A fastening member for fastening and connecting the first coupler housing and the second coupler housing; And One end is supported by the fastening member and the other end is a first spring for applying an elastic force to the plurality of first lock pins, and one end is supported by the fastening member on the opposite side of the fastening member and the other end is elastic force to the plurality of second lock pins A second spring for applying; includes, a plurality of first guide projections are formed in the first coupler housing so that the plurality of first lock pins are spaced apart at regular intervals from the inside of the first coupler housing. In addition, a plurality of second guide protrusions may be formed in the second coupler housing so that the second lock pins are spaced apart at regular intervals from the inside of the second coupler housing.

As an example related to the present invention, the first coupler housing and the second coupler housing have a change in thickness, and the outer diameter of the end where the inlet is located is smaller than the outer diameter of the end where the fastening hole is located, and the inlet is The inner diameter of the located end may be formed smaller than the inner diameter of the end where the fastening hole is located.

As an example related to the present invention, the first coupler housing and the second coupler housing are hollow, each having an inner circumferential surface in contact with the plurality of first lock pins and the plurality of second lock pins, and the inner circumferential surface is the It may have a first taper of a first angle so that the diameter decreases toward the entrance.

As an example related to the present invention, the first guide protrusion and the second guide protrusion may protrude in the central circumferential surface of the first coupler housing and the second coupler housing and extend in the longitudinal direction. have.

As an example related to the present invention, the first guide protrusion and the second guide protrusion may include at least two tapers having different angles. In this case, the at least two tapers include a second taper formed at a second angle in the direction of the fastening hole starting from the inlet side; And a third taper formed at a third angle in the direction of the fastening hole from the end point of the second taper.

As an example related to the present invention, the third angle may be formed larger than the second angle.

As an example related to the present invention, the third angle may be the same as the first angle.

As an example related to the present invention, the first guide protrusion and the second guide protrusion may be formed to decrease in width toward the fastening hole in a section having the second taper.

A method of manufacturing a reinforcing bar coupler according to the present invention includes forming an inlet for inserting a reinforcing bar and a first coupler housing and a second coupler housing each having a fastening hole opposite the inlet; Forming a plurality of first lock pins installed in the first coupler housing and a plurality of second lock pins installed in the second coupler housing; Forming a fastening member for fastening and connecting the first coupler housing and the second coupler housing; And One end is supported by the fastening member and the other end is a first spring for applying an elastic force to the plurality of first lock pins, and one end is supported by the fastening member on the opposite side of the fastening member and the other end is elastic force to the plurality of second lock pins Forming a second spring for applying, and forming a first coupler housing and a second coupler housing, each having an inlet for insertion of the reinforcing bar and a fastening hole on the opposite side of the inlet, is a heated metal material. Performing primary forging by the first mold with respect to; And forming a guide projection on the inner wall of the material by performing secondary forging by a second mold on the material that has undergone the primary forging step.

As an example related to the present invention, the method of manufacturing the reinforcing bar coupler, after the step of forming a guide projection on the inner wall of the material by performing secondary forging on the material that has undergone the first forging step, punches the inlet. It may further include the step of performing a third forging by a third mold so as to be possible.

According to the rebar coupler related to the present invention, a plurality of first guide protrusions so that a plurality of first lock pins and a second lock pin are spaced apart at regular intervals of the first coupler housing and the second coupler housing, and By forming the second guide protrusion, it is possible to obtain a simplification of the configuration and a reduction in manufacturing cost compared to a conventional technique in which a part serving to maintain a constant distance between the lock pins is separate from the coupler housing. In particular, compared to the case of placing a spacer made of a resin material, the performance of fixing and separating rebar is improved.

The coupler housing related to the present invention forms a shape and a structure of a body and a guide protrusion through forging in a metal material, minimizing waste of material during manufacturing and reliability in terms of lockability and fastening force of a rebar occurring at a friction or contact area This is excellent.

In addition, the reinforcing bar coupler to which the coupler housing related to the present invention is applied has the advantage of being applicable to various structures or civil structures requiring earthquake resistance because it can improve the rigidity while saving material by minimizing the number of parts.

1 is a cross-sectional view showing a state in which two reinforcing bars are connected to a reinforcing bar coupler 100 related to the present invention.
2 is a perspective view of a coupler housing 110 related to the present invention.
3 is a side view of the coupler housing 110 of FIG. 2.
4 is a longitudinal sectional view of the coupler housing 110 of FIG. 2.
5 and 6 are views schematically showing molding devices for manufacturing a coupler housing related to the present invention.

Hereinafter, a rebar coupler and a manufacturing method related to the present invention will be described in detail with reference to the accompanying drawings.

According to FIG. 1, the upper and lower two rebars RB1 and RB2 are connected by a rebar coupler 100 related to the present invention. In order to use the reinforcing bar coupler 100, the operator inserts and installs the reinforcing bar coupler 100 assembled in the lower reinforcing bar RB2, and inserts the reinforcing bar RB1 from the top to complete the work. The working time for connecting the reinforcing bars is significantly shortened in this regard, and the work also has a simple advantage.

The reinforcing bar coupler 100 includes a first coupler housing 110A and a second coupler housing 110B, a plurality of first lock pins 120A, a plurality of second lock pins 120B, a fastening member 130, and a first spring ( 140A) and a second spring 140B. The plurality of first lock pins 120A can move in the vertical direction within the first coupler housing 110A, and as they move upward, the gap between each other narrows, thereby increasing the frictional force for the reinforcing bar RB1. Conversely, when the entered reinforcing bar (RB1) is subjected to a tensile force, the plurality of first locking pins (120A) transmits the tensile force to the lower reinforcing bar (RB2) by friction with the reinforcing bar (RB1). The plurality of second locking pins 120B is also configured such that the lower reinforcing bar RB2 in the second coupler housing 110B exerts a strong binding force in one direction.

The fastening member 130 connects the first coupler housing 110A and the second coupler housing 110B by fastening. The fastening member 130 may have a shape such as 'H' when viewed in a cross-sectional shape. This form is easy to support the spring (140A, 140B), provides a space for entering the reinforcing bar (RB1, RB2). As described later, the fastening member 130 may be primarily shaped by forging, such as the coupler housings 110A and 110B and the lock pins 120A and 120B. Thereafter, a screw tab is formed on the outer circumferential surface of the fastening member 130.

The first spring 140A and the second spring 140B are supported at one end by a fastening member 130, and opposite ends are supported by a plurality of first lock pins 120A and second lock pins 120B, respectively, to provide a first lock pin ( 120A) and the second locking pin 120B are installed to apply elastic force. The springs 140A and 140B allow the first lock pins 120A and the second lock pins 120B to move slightly in the direction of the fastening member 130 while the reinforcing bars RB1 and RB2 enter, while restoring to the restoring force. By this, the first locking pin 120A and the second locking pin 120B serve to maintain the fixed reinforcing bars RB1 and RB2.

In FIG. 1, the right cross-section shows that the reinforcing bars RB1 and RB2 are fixed by the first lock pins 120A and the second lock pins 120B inside the first coupler housing 110A and the second coupler housing 110B. The left cross section shows that the spacing between the individual lock pins constituting the plurality of first lock pins 120A and the plurality of second lock pins 120B is limited by the guide protrusions 115A and 115B. That is, the right and left cross-sections of FIG. 1 are adjusted for cutting with respect to the present invention. The detailed description of the guide protrusions 115A and 115B will be mainly described with reference to FIG. 2 or less.

FIG. 2 is a perspective view of the coupler housing 110 related to the present invention, FIG. 3 is a side view of the coupler housing 110 of FIG. 2, and FIG. 4 is a longitudinal sectional view of the coupler housing 110 of FIG. 2.

As shown in these drawings, the coupler housing 110 is formed in a hollow, substantially cylindrical shape with variations in diameter and thickness. The inlet 111 having a small diameter of the coupler housing 110 is a side where the reinforcing bar enters, and the fastening hole 113 having a large diameter becomes a side to which the fastening member 130 described above is fastened. Specifically, the outer diameter of the end where the inlet 111 of the coupler housing 110 is located is smaller than the outer diameter of the end where the fastening hole 113 is located, and the inner diameter of the end where the inlet 111 is located is the fastening hole 113. It is formed smaller than the inner diameter of the located end. As will be described later, such a shape feature, while obtaining the required diameter and strength through the forging of steel, it becomes an easy form to secure the locking force of the lock pin to be hooked.

According to FIG. 4, the coupler housing 110 is hollow, and includes the inner circumferential surfaces to which the lock pins 120A and 120B described above are in contact, and the inner circumferential surface has a first angle θ ₁ to decrease in diameter toward the inlet 111. ) Has a first taper T1. The shape of the inner circumferential surface of the coupler housing 110 allows the fastening force for the reinforcing bar to be secured as the distance between the lock pins 120A and 120B toward the inlet 111 decreases.

Guide protrusions 115 are formed on the inner circumferential surface of the coupler housing 110 to guide the direction of movement of the plurality of lock pins 120A and 120B while maintaining a spaced apart space at a predetermined interval. The guide protrusion 115 protrudes in the direction of the central axis from the inner circumferential surface of the coupler housing 110 and extends in the longitudinal direction. The guide protrusion 115 has a certain length, and the protruding amount from the inner circumferential surface may have certain conditions according to the manufacturing method related to the present invention. Specifically, the guide projection 115 has at least two tapers having different angles. According to FIG. 4, these two tapers are formed of a second taper T2 and a second taper T2 formed at a second angle θ ₂ in the direction of the fastening hole 113 starting from the inlet 111 side. It may include a third taper (T3) formed at a third angle (θ ₃ ) in the direction of the fastening hole 113 from the end point. The third angle θ ₃ is greater than the second angle θ ₂ , and the third angle θ ₃ and the first angle θ ₁ may be the same. Most of the section of the first taper T1 having a large change in inner diameter serves to keep the height of the guide protrusion 115 constant by keeping the third angle θ ₃ of the third taper T3 similar. . On the other hand, the portion of the coupler housing 110 close to the inlet 111 becomes narrower as the thickness thereof becomes relatively thick, and accordingly, the second angle θ ₂ of the second taper T2 is the third angle. By making it smaller than (θ ₃ ), the shape of the guide protrusion 115 ends without a step at the entrance 111 side. In either case, the second angle θ ₂ of the second taper T2 is a positive angle (ie, having a positive angle in the direction of the fastening hole 113 with respect to the axis X parallel to the central axis) As a result, the guide protrusion 115 can be formed by a punch in the forging process described later.

The guide protrusion 115 may be formed to decrease in width toward the fastening hole 113 in the section having the second taper T2. That is, as shown in FIG. 4, the width at the start point of the second taper T2 is W ₁ and the width at the end point is W ₂ , so that W ₂ is smaller than W ₁ . The variable width of the guide projection 115 serves to accurately ensure the stopping effect when the lock pins 120A and 120B move.

Hereinafter, a method of manufacturing the reinforcing bar coupler 100 related to the present invention will be described. The manufacturing process of the reinforcing bar coupler includes forming a coupler housing having an inlet for inserting the reinforcing bar and a fastening hole on opposite sides of the inlet, and forming a plurality of lock pins installed in the coupler housing, and the coupler housing and the coupler housing. A step of forming a fastening member to be connected by fastening may be included, and one end may be supported by the fastening member and the other end may include forming a spring that applies elastic force to the plurality of lock pins. In the double coupler housing, the first forging is performed by the first mold on the heated metal material, and the second forging is performed by the second mold on the material that has undergone the first forging step to guide the inner wall of the material. It can be produced by the step of forming a step and performing a third forging by a third mold so as to perforate the inlet. In addition, the lock pins 120A and 120B and the fastening member 130 may also be manufactured by a forging process. The manufacturing method by such forging can secure the correct shape and stiffness and improve the mass productivity, while also allowing the rebar to be strongly bound by simple operation, which is the basic function of the quick coupler.

5 and 6 schematically show molding apparatuses for manufacturing a coupler housing related to the present invention, FIG. 5 is a molding apparatus 200 using a second mold, and FIG. 6 is a molding apparatus using a third mold ( 300). Prior to the second mold operation, an intermediate material having a concave groove through a first mold is obtained from a rod-like material cut into a certain length. As shown in FIG. 5, the two-step forming apparatus 200 has a coupler housing intermediate 110 ′ having a detailed shape through a die 210 having an outer shape of the coupler housing and a punch 220 having an inner peripheral surface shape of the coupler housing. ). The punch 220 includes a groove-shaped portion 221 corresponding to the guide projection 115 of the coupler housing. The die 210 may be provided with a support mold 230 for supporting a portion on the inlet side of the coupler housing during the punching process.

Next, as shown in FIG. 6, a trimming step is performed through a molding apparatus 300 equipped with a punch 310 for forming a die 310 having a punch groove and an inlet 111. Through this, a coupler housing intermediate 110 "on both sides is obtained, and a final coupler housing is formed through a process such as thread tapping.

The reinforcing bar coupler described above and its manufacturing method are not limited to the configuration and method of the described embodiments. The above embodiments may be configured by selectively combining all or part of each embodiment so that various modifications can be made.

100: rebar coupler 110, 110A, 110B: coupler housing
111: Entrance 113: Fastening hole
115, 115A, 115B: Guide projection 120A, 120B: Lockpin
130: fastening member 140A, 140B: spring
T1: First taper T2: Second taper
T3: Third taper

Claims (12)

A first coupler housing and a second coupler housing each having an inlet for inserting a reinforcing bar and a fastening hole opposite the inlet;
A plurality of first lock pins installed on the first coupler housing and a plurality of second lock pins installed on the second coupler housing;
A fastening member for fastening and connecting the first coupler housing and the second coupler housing; And
One end is supported by the fastening member and the other end is a first spring that applies elastic force to the plurality of first lock pins, and one end is supported by the fastening member on the opposite side of the fastening member and the other end is elastic to the plurality of second lock pins. The second spring to be added; includes,
A plurality of first guide protrusions are formed in the first coupler housing so that the plurality of first lock pins are spaced apart at regular intervals from the inside of the first coupler housing,
A plurality of second guide projections are formed in the second coupler housing so that the second lock pins are spaced apart at regular intervals from the inside of the second coupler housing,
The first coupler housing and the second coupler housing have a change in thickness,
The outer diameter of the end where the inlet is located is smaller than the outer diameter of the end where the fastening hole is located, and the inner diameter of the end where the inlet is located is smaller than the inner diameter of the end where the fastening hole is located,
The first coupler housing and the second coupler housing are hollow, each having an inner circumferential surface in contact with the plurality of first lock pins and the plurality of second lock pins,
The inner peripheral surface has a first taper of a first angle so that the diameter decreases toward the entrance,
The first guide protrusion and the second guide protrusion are formed to protrude in the central axis direction from the inner circumferential surfaces of the first coupler housing and the second coupler housing and extend in the longitudinal direction,
The first guide protrusion and the second guide protrusion include at least two tapers having different angles,
The at least two tapers,
A second taper formed at a second angle in the direction of the fastening hole starting from the entrance side; And
And a third taper formed at a third angle in the direction of the fastening hole from the end point of the second taper,
The third angle is greater than the second angle,
The third angle is the same as the first angle,
The first guide protrusion and the second guide protrusion are formed such that the width decreases toward the fastening hole in a section having the second taper.
delete delete delete delete delete delete delete delete Forming a first coupler housing and a second coupler housing each having an inlet for inserting a reinforcing bar and a fastening hole on the opposite side of the inlet;
Forming a plurality of first lock pins installed in the first coupler housing and a plurality of second lock pins installed in the second coupler housing;
Forming a fastening member for fastening and connecting the first coupler housing and the second coupler housing; And
One end is supported by the fastening member and the other end is a first spring that applies elastic force to the plurality of first lock pins, and one end is supported by the fastening member on the opposite side of the fastening member and the other end is elastic to the plurality of second lock pins. And forming a second spring to be applied.
The step of forming a first coupler housing and a second coupler housing each having an inlet for inserting the reinforcing bar and a fastening hole on the opposite side of the inlet,
Subjecting the heated metal material to primary forging by a first mold;
Forming a guide projection on the inner wall of the material by performing secondary forging by a second mold on the material that has undergone the primary forging step; And
And performing a third forging by a third mold so as to puncture the entrance,
The first coupler housing and the second coupler housing have a change in thickness,
The outer diameter of the end where the inlet is located is smaller than the outer diameter of the end where the fastening hole is located, and the inner diameter of the end where the inlet is located is smaller than the inner diameter of the end where the fastening hole is located,
The first coupler housing and the second coupler housing are hollow, each having an inner circumferential surface in contact with the plurality of first lock pins and the plurality of second lock pins,
The inner peripheral surface has a first taper of a first angle so that the diameter decreases toward the entrance,
The first guide protrusion and the second guide protrusion are formed to protrude in the central axis direction from the inner circumferential surfaces of the first coupler housing and the second coupler housing and extend in the longitudinal direction,
The first guide protrusion and the second guide protrusion include at least two tapers having different angles,
The at least two tapers,
A second taper formed at a second angle in the direction of the fastening hole starting from the entrance side; And
And a third taper formed at a third angle in the direction of the fastening hole from the end point of the second taper,
The third angle is greater than the second angle,
The third angle is the same as the first angle,
The first guide projection and the second guide projection is formed so that the width decreases toward the direction of the fastening hole in the section having the second taper, the method of manufacturing a reinforcing bar coupler. delete delete

Images