JP2010042428A - Apparatus for manufacturing unit reinforcement - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an apparatus for manufacturing a unit reinforcement having a mechanism for bending the front end parts of a vertical reinforcement and winding them around a main reinforcement until at least the front end parts of the vertical reinforcement reach positions where the front end parts intersect the non-bent portions of the vertical reinforcement. <P>SOLUTION: The apparatus for manufacturing a unit reinforcement is provided with: guide means 12, 13 for guiding main reinforcements 2, 2, which are disposed in both side-edges, and web reinforcements 3, 3, a plurality of which is disposed between the main reinforcements 2, 2, respectively; a vertical reinforcement feeding means 30 for feeding a vertical reinforcement 1 to the position where the main reinforcements 2, 2 and the web reinforcements 3, 3, which are guided by the guide means 12, 13, are orthogonally intersected; a bending means 20 for curving both side-edges of the vertical reinforcement 1, and for bending the side-edges and winding them around the main reinforcements 2 until at least the front end parts of the vertical reinforcement 1 reach positions where the front end parts intersect the non-bent portions of the vertical reinforcement 1; a weld means for welding the cross points of the web reinforcements 3, 3 and the vertical reinforcement 1; and a pulling device 50 for moving, by a predetermined pitch width, the unit reinforcement in which bending of the vertical reinforcement 1 is finished and welding thereof to the web reinforcement 3 is finished. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a unit rebar manufacturing apparatus, and more particularly, a lattice-like structure embedded in concrete to reinforce a concrete building or structure including a foundation such as a building or a concrete structure. The present invention relates to a unit rebar manufacturing apparatus.

  Conventionally, when constructing a reinforced concrete structure, the bar arrangement work that arranges the reinforcing bars vertically and horizontally at predetermined intervals is performed manually by craftsmen. Units are formed by bundling each intersecting portion framed vertically and horizontally by a plurality of abdominal muscles arranged parallel to each other and perpendicularly arranged with a tie wire made of mild steel wire or by welding. Reinforcing bars were constructed.

Reinforcing bars used for unit reinforcing bars have standardized reinforcing bars with hooks whose ends are bent at a predetermined angle. For example, 90-degree hooks with the ends of the reinforcing bars bent at right angles, 135 degrees, and 180 degrees There are 135-degree hooks and 180-degree hooks that are bent.
However, these hooks are only used to make a frame with reinforcing bars arranged in the crossing direction, and binding wires and welding have been used to connect both vertical and horizontal reinforcing bars.

In addition, as a reinforced concrete (RC) foundation for low-rise industrialized houses (prefabricated houses) and conventional wooden houses, it is common to use a unit rebar assembled in advance at the factory stage. This unit rebar is placed in a basic module preset in the target prefabricated house, and then a formwork is installed around the placed unit rebar, and concrete is placed in this formwork to build an RC foundation. To do.
For example, Japanese Patent Laid-Open No. 11-36589 (Patent Document 1) and Japanese Patent Laid-Open No. 06-57874 (Patent Document 2) are known as unit reinforcing bars, and the transverse muscles (main and abdominal muscles) and longitudinal muscles are all bound. Or it is connected using welding.

  In the unit reinforcing bars of Patent Documents 1 and 2, there are many connecting portions of the horizontal bars and the vertical bars, and much time and labor are required for the work of the frame and the connection. Further, in the connection by welding, since the reinforcing bar as the base material is melted, there are problems such as loss of cross-sectional area, difficulty in thermal management, and reduction in structural strength of the reinforcing bar. In particular, in the case of unit reinforcing bars, if welding heat is applied to the main bars on both sides held by the shear reinforcing bars, the strength of the main bars may be reduced and the material may be changed.

  Therefore, the inventor of the present application reduces productivity and workability by reducing the number of binding wires and welding points as much as possible when connecting rebars in a lattice shape to reduce unit strength due to welding heat. A patent application was filed in order to provide a unit rebar connection method that can prevent problems such as changes in material and material as much as possible (Japanese Patent Application No. 2007-045923). This method of fixing the vertical stripes is conventionally performed by bending the end portion to 135 ° or 180 °, whereas the vertical stripe end portion is bent and fixed to, for example, 225 ° so as to be in close contact with the main reinforcement. This is a method, and the strength and stability of the reinforcing bar can be greatly increased as compared with the conventional method.

  The unit reinforcing bar connection method has a characteristic that spring back is unlikely to occur because the tip end side of one reinforcing bar is bent back to the reinforcing bar and overlapped. Further, the tip side of the end portion of the reinforcing bar protrudes from the reinforcing bar to the side opposite to the bent portion, so that the spring back is further less likely to occur.

  On the other hand, Japanese Patent Application Laid-Open No. 2003-205319 discloses a rebar bending process, a unit, and a rebar bending apparatus using the unit (Patent Document 3). This rebar bending process and unit and the rebar bending apparatus using it have bending claws that rotate around the guide shaft, and the bending claws perform bending according to the diameter of the guide shaft. is there.

JP 11-36589 A Japanese Patent Laid-Open No. 06-57874 JP2003-205319A

  The above-described unit rebar connection method provides an unprecedented unit rebar, and an object of the present invention is to provide such a unit rebar manufacturing apparatus. And it aims at mass-production and cost reduction of unit rebar with high stability and intensity.

  Here, the rebar bending process and the unit and the rebar bending apparatus using the same in Patent Document 3 are formed by bending both ends of the rebar in a ring shape, as in the unit rebar connection method described above. Furthermore, it does not include a mechanism that bends at least until the leading end of the vertical stripe crosses the unfolded portion of the vertical stripe. Further, when the vertical bars are wound around the horizontal bars by the bending process of the reinforcing bars and the unit and the reinforcing bar bending apparatus using the unit of Patent Document 3, when the vertical bars are bent over 180 ° to 225 °, the ends of the vertical bars However, the vertical bars cannot be wrapped around the main bars in close contact with the main bars.

  In view of the above, the present invention can provide a device for realizing the above-described method for connecting unit reinforcing bars, in which the longitudinal bars can be bent over 180 ° to 225 °. Specifically, it is an object of the present invention to provide a unit reinforcing bar manufacturing apparatus including a mechanism that bends at least a tip of a vertical bar to a position where it intersects with an unfolded portion of the vertical bar and winds it around the main bar.

  In the present invention, the longitudinal bars are automatically arranged in a direction perpendicular to the main and abdominal muscles at predetermined intervals, the intersections of the abdominal muscles and the longitudinal muscles are welded, and the unit rebars are automatically repeated by sequentially repeating them. An object of the present invention is to provide an apparatus for manufacturing a unit reinforcing bar that can be manufactured automatically.

  In order to achieve the above object, the present invention according to claim 1 is a unit reinforcing bar manufacturing apparatus in which reinforcing bars are combined in a lattice shape, and a plurality of abdominal muscles arranged between the main muscles and the main muscles arranged on both end sides, respectively. Guide means for guiding, vertical muscle supply means for supplying vertical muscles to positions orthogonal to the main muscles and abdominal muscles guided by the guide means, and both ends of the vertical muscles are curved, and at least the longitudinal muscle ends are longitudinal muscles. Bending means that folds to the position where it intersects with the non-bending part and wraps around the main bar, welding means that welds the intersection of the abdominal muscle and the longitudinal muscle, and the unit that has finished bending the longitudinal muscle and welding the abdominal muscle and the longitudinal muscle And a tension device that moves the reinforcing bar at a predetermined pitch width.

  In order to achieve the above object, according to a second aspect of the present invention, in the unit reinforcing bar manufacturing apparatus according to the first aspect of the present invention, the bending means is a cylindrical main bar guide into which the main bar is inserted. The main muscle guide is formed to include a main bar guide formed with an inclined tip on the side from which the bar protrudes, and a roller member that abuts on the vicinity of the vertical bar protruding from the front end of the main bar guide and winds around the main bar. And

  In order to achieve the above object, according to a third aspect of the present invention, there is provided the unit reinforcing bar manufacturing apparatus according to the first or second aspect, wherein the bending means abuts on the tip of the vertical bar to perform positioning. It is characterized by having.

  In order to achieve the above object, according to a fourth aspect of the present invention, in the unit reinforcing bar manufacturing apparatus according to any one of the first to third aspects, the main muscle and the plurality of abdominal muscles are guided by the guide means. A positioning pusher for aligning the main muscle and the plurality of abdominal muscles by abutting the end portions is provided.

  In order to achieve the above object, the present invention according to claim 5 is the unit rebar manufacturing apparatus according to any one of claims 1 to 4, wherein a predetermined number of longitudinal bars have been attached. A stock conveyor for sequentially stacking and stocking reinforcing bars, and further comprising a stock conveyor for transferring to a next process when a predetermined number of unit reinforcing bars are stacked.

  According to the unit reinforcing bar manufacturing apparatus according to the present invention, the both ends of the longitudinal bar are bent and wound around the main bar so that at least the tip of the longitudinal bar is bent until it reaches the position where the unfolded portion of the vertical bar intersects. Compared to the conventional case, there is an effect that it is possible to automatically and inexpensively manufacture a unit reinforcing bar which has improved the fixing property of the main reinforcement in the concrete and has greatly increased the stability and strength of the quality.

  Further, according to the unit reinforcing bar manufacturing apparatus of the present invention, since a predetermined number of completed unit reinforcing bars are transferred to the stock conveyor, there is an effect that it is convenient for transportation and storage.

  Further, according to the unit reinforcing bar manufacturing apparatus according to the present invention, since heat is not applied to the main bar, the mechanical properties of the main bar are not impaired, management of the main bar welding portion is unnecessary, and the electric power for welding the main bar is eliminated. There is an effect that energy can be greatly reduced.

  Further, according to the unit reinforcing bar manufacturing apparatus according to the present invention, since the unit reinforcing bar is manufactured while being managed in the factory, the quality is stable and the processing time can be shortened as compared with the reinforcing bar of the field set. There is.

  Hereinafter, a unit reinforcing bar manufacturing apparatus according to the present invention will be described in detail with reference to the drawings. Fig.1 (a) is a top view of one Embodiment of the manufacturing apparatus of the unit reinforcement which concerns on this invention, (b) is the side view.

  The unit reinforcing bar manufacturing apparatus 10 shown in the figure schematically includes a guide portion 12 that is a guide means for guiding the main muscles 2 and 2 disposed on both ends, and a plurality of abdominal muscles 3 disposed between the main bars 2 and 2. Guide section 13 which is a guide means for guiding 3 and longitudinal muscle which is a longitudinal muscle supply means for supplying the longitudinal muscle 1 to a position orthogonal to the main muscles 2 and 2 and the abdominal muscles 3 and 3 guided by the guide sections 12 and 13. The main device 2, 2 is bent by bending both ends of the supply device 30 and the longitudinal bar 1 until at least the distal end portion 1 b of the longitudinal bar 1 intersects the non-bending portion 1 a which is a linear portion of the longitudinal bar 1. A bending device 20 which is a bending means for winding the wire, spot welding devices 40 and 40 which are welding means for welding the intersection 6 of the abdominal muscles 3 and 3 and the longitudinal muscle 1, bending of the longitudinal muscle 1 and abdominal muscles 3 and 3 The unit that has been welded to the vertical bar 1 It is constituted by a tensioning device 50 for moving the reinforcing bars 5 at a predetermined pitch.

  The main muscle 2 and the abdominal muscle 3 are generally long members formed in a predetermined length, and are formed of a steel material. Further, the main bar 2 and the abdominal bar 3 may be round bars having a circular cross section, deformed bars having ribs on the outer peripheral surface, or other shapes, and high-strength bars or ultra-high-strength bars can also be used. Is not limited to this.

  As shown in FIG. 3, the guide portion 12 that is a main muscle guide into which the main muscle 2 is inserted is formed in a cylindrical body into which the main muscle 2 can be inserted, and is arranged as a part of a bending device 20 described later. . And the front-end | tip part 12a of the guide part 12 in the side from which the main reinforcement 2 protrudes is formed so that it may incline diagonally. As will be described later, by bending the longitudinal streaks 1 along this inclination, the longitudinal streaks 1 can be bent at least 225 ° or more without contacting the unfolded portion 1a without contacting the longitudinal streaks 1 themselves. It is like that.

  On the other hand, the guide portion 13 is formed by a cylindrical member having a hollow inside and is disposed between the guide portions 12 and 12, similarly to the guide portion 12. And the abdominal muscles 3 and 3 are guided by inserting and arranging the abdominal muscles 3 and 3 inside the guide part 13. In FIG. 1A, the guide portions 13 are provided at two locations, but the present invention is not limited to this, and an appropriate number of guide portions 13 can be installed according to the configuration of the unit reinforcing bars 5.

  Here, the unit reinforcing bar manufacturing apparatus 10 is positioned so as to abut on the rear end portions of the main muscles 2 and 2 and the abdominal muscles 3 and 3 having predetermined lengths arranged in the guide portions 12 and 13, respectively. A pusher 60 is provided. The positioning pusher 60 is configured by a contact plate 65 and a cylinder member 61 for pushing the contact plate 65 forward disposed on a base 63 having a predetermined height. Thereby, relative positioning of the transverse muscle is performed by the contact plate 65 pressing the rear ends of the main muscles 2 and 2 and the abdominal muscles 3 and 3 set in the guide portion 12 and the guide portion 13, respectively. Yes. In this embodiment, a guide base 70 that supports the main muscles 2 and 2 and the abdominal muscles 3 and 3 is disposed between the positioning pusher 60 and the guide portions 12 and 13.

  The bending devices 20 are arranged at two positions on both ends, respectively, and as shown in FIG. 3, the distal ends of the longitudinal bars 1 arranged so as to be orthogonal to the main bars 2 protruding from the distal ends 12 a of the guide parts 12. 1b is provided with a roller member 21 that rotates in contact with the vicinity of 1b, and the roller member 21 transmits power from a drive mechanism including a motor 25, an idle gear 26, and a main gear 27 via an arm 23. It is designed to drive. Then, as shown in FIG. 4, the roller member 21 is pressed along the drum 22 having the rotation center A while being in contact with the vicinity of the end portion 1 b of the vertical bar 1, thereby the end of the vertical bar 1. The portion 1b and the vicinity are bent so as to be wound around the main bar 2. At this time, since the tip 12a side of the guide portion 12 is inclined, the vicinity of the end 1b of the vertical bar 1 is wound obliquely around the main bar 2, so that the front end 1b of the vertical bar 1 collides with its own unfolded part 1a. For example, it can be bent at 225 ° (see FIG. 5).

  Also, as shown in FIG. 4, the guide portion 12 that guides the main bar 2 is disposed at a position slightly decentered from the rotation center A of the bending device 20. Thereby, the roller member 21 can be pressed while being in contact with the vicinity of the end 1b of the vertical bar 1 and bent up to 225 °.

  On the other hand, the bending device 20 includes a positioning mechanism 29 that performs positioning by contacting the end 1b of the longitudinal bar 1. The positioning mechanism 29 includes a main body 29a and an abutting body 29b arranged so as to protrude from the main body 29a, and is attached to both of the folding devices 20 arranged on both sides in a direction in which the abutting body 29b faces each other. It has been. When the vertical streak 1 is supplied from a vertical streak supply device 30 to be described later, both contact bodies 29b and 29b advance by a predetermined length, and alignment is performed so as to sandwich the vertical streak 1 therebetween. It has become.

  Between the bending apparatuses 20 and 20 arrange | positioned at both sides, as shown in FIG. 2, the spot welding apparatuses 40 and 40 which weld the intersection 6 of the longitudinal muscle 1 and the abdominal muscles 3 and 3 are arrange | positioned. Thereby, the intersection 6 of the longitudinal muscle 1 and the abdominal muscles 3 and 3 is firmly joined. In the present embodiment, the spot welding devices 40 and 40 are arranged at two locations. However, the present invention is not limited to this, and an appropriate number can be installed according to the configuration of the abdominal muscles 3 of the unit reinforcing bars 5. Needless to say.

  As shown in FIG.1 (b), the vertical streak supply apparatus 30 is arrange | positioned in the front position rather than the bending apparatus 20, and the upper position of a line. The vertical streak supply device 30 accommodates a large number of vertical streaks 1 and a supply conveyor that transports the vertical streaks 1 one by one from the storage box 31 and supplies the vertical streaks 1 to the position for folding by the folding device 20. 33 is formed. As a means for supplying the vertical bars 1 stored in the storage box 31 to the supply conveyor 33 one by one, an appropriate method can be adopted. In FIG. 1A, the vertical streak supply device 30 is omitted.

  On the other hand, a tension device 50 is provided on the lower side of the vertical bar supply device 30 to move the unit reinforcing bars 5 that have been wound and welded with the vertical bars 1 with a predetermined pitch size. The tension device 50 includes two chuck arms 51 and 51 that sandwich the longitudinal bars 1 that have been wound and welded, and is configured to be movable along rails 53 and 53 that are arranged on both the left and right sides. Yes. The longitudinal bars 1 to be attached next are positioned by pulling the chuck arms 51, 51 toward the tensioning device 50 by a predetermined distance. Then, every time the winding and welding of the vertical bars 1 are completed, the unit reinforcing bars 5 are pulled by a predetermined interval. Then, it is determined by the number of pulls that the predetermined number of vertical bars 1 have been attached, and the operation is returned to the original position and repeated.

  In addition, the unit reinforcing bar manufacturing apparatus 10 includes a stock conveyor 80 that sequentially stacks and stocks the unit reinforcing bars 5 on which a predetermined number of vertical bars 1 have been attached. The stock conveyor 80 is a conveyor on which the unit reinforcing bars 5 on which all the vertical bars 1 have been attached are mounted, and the gantry 81 that supports them can be expanded and contracted vertically, and the finished unit reinforcing bars 5 are stacked one after another. As the process proceeds, the height position of the stock conveyor 80 can be gradually lowered. When the predetermined number of unit rebars 5 are stacked and the height of the transport surface of the stock conveyor 80 reaches the same height as the transport rollers 90, the stacked unit rebars 5 are transported to the transport rollers. 90 is transferred and transported.

  The operation of each mechanism described above is program-controlled so as to automatically operate according to a predetermined sequence by a control device constituted by a general-purpose computer (not shown).

  Next, operation | movement of the manufacturing apparatus 10 of the unit rebar mentioned above is demonstrated. First, the main muscles 2 and 2 are inserted and set in the guide portions 12 and 12 arranged on both sides, respectively. Further, the abdominal muscles 3 and 3 are inserted and set in the guide portions 13 and 13 disposed between the guide portions 12 and 12, respectively. The following operation is continuously performed by a control device (not shown). That is, the positioning pusher 60 presses the end surfaces of the main muscles 2 and 2 and the abdominal muscles 3 and 3 to perform alignment so that the entire lengths are aligned.

  When the alignment of the main muscles 2, 2 and the abdominal muscles 3, 3 is completed, one vertical muscle 1 is brought into a direction orthogonal to the extending direction of the main muscles 2, 2 and the abdominal muscles 3, 3 by the supply conveyor 33 of the vertical muscle supply device 30. Supplied. At this time, the position of the vertical stripe 1 is adjusted by the positioning mechanism 29 provided in the left and right bending apparatuses 20.

  When the positioning of the vertical muscle 1 is completed, the intersection 6 between the vertical muscle 1 and the abdominal muscles 3 and 3 is welded by the spot welding devices 40 and 40. At the same time, both end portions of the longitudinal bar 1 are bent by the bending devices 20 and 20 so as to be wound around the main bars 2 and 2, respectively. Specifically, the roller member 21 attached to the arm 23 rotates about 260 ° around the center of rotation A along the drum 22 and presses while contacting the vicinity of the end 1b of the vertical bar 1 to generate the vertical bar. The vicinity of the end 1b of 1 is wound around the main muscle 2. At this time, since the distal end portion 12a of the guide portion 12 is inclined, the vicinity of the end portion 1b of the vertical bar 1 is bent at 225 ° without hitting the non-bending portion 1a which is a linear portion which is the main body of the vertical bar 1. (See FIG. 6). When the bending of the vertical stripe 1 is completed, the arm 23 rotates in the reverse direction and returns to the original position.

  When the bending of the front end 1b of the vertical bar 1 and the welding of the intersection point 6 are completed, the tensioning device 50 engages the chuck arms 51 and 51 with the front vertical bar 1 and pulls it toward the tensioning device 50 by a predetermined pitch width. . Then, the next vertical stripe 1 is supplied from the vertical stripe supply device 30 and the above operation is repeated a predetermined number of times.

  When the predetermined number of vertical bars 1 are attached, the unit reinforcing bars 5 are placed on the stock conveyor 80. The stock conveyor 80 descends by the height of the unit reinforcing bar 5 for one sheet, and then waits at a position where the completed unit reinforcing bar 5 can be stacked thereon. The operation is repeated each time the completed unit rebars 5 are sent one after another, a predetermined number of unit rebars 5 are stacked, and the height of the conveying surface of the stock conveyor 80 is the same height as the conveying rollers 90. Then, the stacked unit reinforcing bars 5 are transferred to the conveyance roller 90 and conveyed to the next process.

  As described above, according to the unit reinforcing bar manufacturing apparatus according to the present invention, it is possible to automatically fix a unit reinforcing bar which has improved the fixing property of the main reinforcing bar in the concrete and greatly increased the stability and strength of the quality compared to the conventional case. In a short time and at low cost.

  As described above, the preferred embodiment of the present invention has been described in detail. However, the present invention is not limited to the specific embodiment, and within the scope of the gist of the present invention described in the claims, Needless to say, various modifications and changes are possible.

(A) is a top view of one Embodiment of the manufacturing apparatus of the unit reinforcement which concerns on this invention, (b) is the side view. It is explanatory drawing which shows attachment of the vertical muscle to a main muscle and an abdominal muscle. It is a partial expanded sectional view of a bending apparatus. It is explanatory drawing for demonstrating the bending of the front-end | tip part of a vertical line by a roller member. It is a top view which shows the winding state to the main reinforcement of a vertical line. (A) is a figure which shows before bending of a vertical line, (b) is a figure which shows the state which bent the edge part of the vertical line. It is a top view of one embodiment of a unit rebar.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Longitudinal muscle 2 Main muscle 3 Abdominal muscle 6 Intersection 10 Unit rebar manufacturing apparatus 12 Guide part 13 Guide part 20 Bending apparatus 21 Roller member 22 Drum 23 Arm 25 Motor 26 Idle gear 27 Main gear 29 Positioning mechanism 29a Main body 29
29b Abutment body 30 Longitudinal line supply device 31 Storage box 33 Supply conveyor 40 Spot welding device 50 Tension device 51 Chuck arm 53 Rail 60 Positioning pusher 70 Guide base 80 Stock conveyor 81 Mounting base 90 Conveying roller

Claims (5)

In the unit rebar manufacturing equipment that combines rebars in a grid pattern,
Guide means for guiding the main muscles arranged at both ends and a plurality of abdominal muscles arranged between the main muscles;
Longitudinal muscle supply means for supplying longitudinal muscles to positions orthogonal to the main and abdominal muscles guided by the guide means;
Bending means for curving both ends of the longitudinal bars, bending the windings to the position where at least the tip of the longitudinal bars intersects with the unfolded portion of the longitudinal bars,
Welding means for welding the intersection of the abdominal muscle and the longitudinal muscle;
A tensioning device for moving the unit reinforcing bars, which have been bent and the welding of the abdominal muscles and the longitudinal bars, with a predetermined pitch width;
An apparatus for manufacturing a unit reinforcing bar, comprising: In the manufacturing apparatus of the unit reinforcing bar according to claim 1,
The bending means is
A cylindrical main muscle guide into which the main muscle is inserted, and a main muscle guide formed with an inclined tip on the side from which the main muscle protrudes;
A roller member that comes into contact with the vicinity of the tip of the vertical bar protruding from the tip of the main bar guide and winds around the main bar;
A connecting device for unit reinforcing bars, comprising: In the manufacturing apparatus of the unit reinforcing bar according to claim 1 or 2,
The bending means is
A connecting device for unit reinforcing bars, comprising a positioning mechanism for positioning by contacting a tip of the longitudinal bars. In the manufacturing apparatus of the unit reinforcing bar according to any one of claims 1 to 3,
A unit rebar connection comprising a positioning pusher for aligning the main muscle and the plurality of abdominal muscles by contacting the main muscles guided by the guide means and the rear end portions of the plurality of abdominal muscles apparatus. In the manufacturing apparatus of the unit reinforcing bar according to any one of claims 1 to 4,
A stock conveyor for sequentially stacking and stocking unit reinforcing bars for which a predetermined number of vertical reinforcing bars have been attached, and further transferring the stock conveyor to the next process when a predetermined number of unit reinforcing bars are stacked A connecting device for unit reinforcing bars, comprising:

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