Patent Abstract:
The present invention provides a reinforcing bar tie the enables the connection intersecting reinforcing bars. The invention houses a tie made of an elastic member in a reception space, and extrudes it with an extruding member. At this time, the curved portions provided on both ends of the tie advance while guiding portions and of a guide member push them open, and are guided to an intersecting position of two reinforcing bars. Further, by extruding with the extruding member the tie detaches from the guiding member and winds around the intersection of the two reinforcing bars with a force sufficient to couple the two reinforcing bars together.

Full Description:
TECHNICAL FIELD 
       [0001]    The present invention relates to a tie for binding materials to be tied such as reinforcing bars, a tie assembly, and a tie attachment device. 
       BACKGROUND OF INVENTION 
       [0002]    Conventionally, reinforcing bars are arranged inside of concrete columns and walls in reinforced concrete buildings. For example, in a reinforced concrete column, a plurality of reinforcing bars are arranged along the direction of the column, and reinforcing bars are further arranged in horizontal direction intersecting with the reinforcing bars in a horizontal direction. Such reinforcing bars are installed prior to pouring concrete in a formwork and an intersectional portion of the reinforcing bar in the vertical direction (vertical reinforcement) and the reinforcing bar in the horizontal direction (horizontal reinforcement) are fixed by twisting a wire. Such procedure of twisting wires takes time and effort, thus connection and fixation tools for fixing intersectional reinforcing bars and devices for twisting wires have been proposed, as follows: 
         [0003]    [Patent document 1] Japanese Published Unexamined Patent Application No. 2005-320816; 
         [0004]    [Patent document 2] Japanese Published Unexamined Utility Model Application No. S60-87930; 
         [0005]    [Patent document 3] Japanese Published Unexamined Utility Model Application No.S61-20625; and 
         [0006]    [Non-patent document 1] Binding machine http)://www9.ocn.ne.ip/{tilde over ( )}tairiku/PicHomePage0/vw 7.html 
       BRIEF SUMMARY OF THE INVENTION 
       [0007]    However, while the conventional connecting tools described above save the effort of twisting wire for binding, it is bulky for preparing large amounts because the ties are in complicated forms. For this reason, it is inconvenient to carry. Also, there is a problem of difficulty in the attachment work. 
         [0008]    Further, the binding machine described in non-patent document 1 is a device having a motor driven by electricity and binds reinforcing bars by twisting wires around, however, the machine is not suitable for working for a long time due to its large weight, and there is a problem of a further increase of the weight when a battery is used because the power wire supplying electricity disturbs the work. 
         [0009]    The present invention has been made in consideration of these issues, and it is therefore an objective of the present invention to: 1) provide a reinforcing bar tie which connects intersectional reinforcing bars; 2) provide a tie assembly that connects a plurality of ties for easy attachment; and 3) provide a tie attachment device for each attachment to the intersectional portion of the reinforcement bars. 
         [0010]    The objectives are achieved by the present invention described as below. 
         [0011]    (1) A tie for twisting around at an intersectional portion of a plurality of materials to be tied to bind these materials, wherein the tie consists of a wire rod made of elastic material formed in an arc, where the clearance between both ends is larger than the minimum width of the bound portion of material to be tied when both ends are opened within an elastic deformation range, and the maximum inner diameter in a restored state is smaller than the maximum width of the bound portion of materials to be tied. 
         [0012]    (2) The tie according to (1) above, wherein the tie is for binding a pair of materials to be tied. 
         [0013]    (3) The tie according to (2) above, wherein an intersectional portion of crossed material to be tied is a bound portion. 
         [0014]    (4) The tie according to (2) above, wherein the bound portion is a portion of overlap of materials to be tied which are arranged in parallel. 
         [0015]    (5) The tie according to any one of (1) to (4) above, wherein both ends of said arc wire rod have curved portions curving opposite to the direction of the curve of the arc. 
         [0016]    (6) The tie according to any one of (1) to (5) above, wherein said wire rod has a rupture portion to be ruptured when a deformation value exceeds an elasticity limit. 
         [0017]    (7) The tie according to (6) above, wherein said rupture portion is provided on the midsection of an axial direction of said wire rod. 
         [0018]    (8) The tie according to (6) or (7) above, wherein said rupture portion is a portion smaller in area of cross-section of said wire rod than another portion. 
         [0019]    (9) The tie according to (8) above, wherein said rupture portion is a groove or a cut formed in a direction perpendicular to the axial direction of said wire rod. 
         [0020]    (10) The tie according to one of any (1) to (9) above, wherein a portion of both end portions of said wire rod is crossing in a restored state. 
         [0021]    (11) The tie according to one of any (1) to (10) above, wherein said wire rod having one, or two or more loops formed in an arc as an overall shape and a portion is configured by curving outward. 
         [0022]    (12) A tie assembly for connecting an inserting member inserted between both ends of a tie through a thin walled connecting portion, wherein the tie consists of a wire rod made of elastic material formed in an arc, the clearance between both ends is larger than the minimum width of the bound portion of material to be tied when both ends are opened within an elastic deformation range, and the maximum inner diameter in a restored state is smaller than the maximum width of the bound portion of material to be tied. 
         [0023]    (13) A tie attachment device consisting of; 
         [0024]    a guiding member positioned between both ends of a tie for guiding to a direction, wherein a tie consists of a wire rod made of elastic material formed in an arc, the clearance between both ends is larger than the minimum width of the bound portion of material to be tied when both ends are opened within an elastic deformation range, and the maximum inner diameter in a restored state is smaller than the maximum width of the bound portion of material to be tied; 
         [0025]    a storing portion positioned between said guiding member for storing the material to be tied; 
         [0026]    an extruding member positioned posterior to said guiding member for extruding a tie forward; and 
         [0027]    an operation means for advancing said extruding member; 
         [0028]    wherein said extruding member is capable of reciprocal motion between a standby position forming a reception space to house a tie between said guiding member, and an attachment position where both ends of a tie exceeding the frond end of the guiding member. 
         [0029]    (14) The tie attachment device according to (13) above, wherein a groove for guiding both end portions of the tie is formed on an outer face of said guiding member. 
         [0030]    (15) The tie attachment device according to (13) or (14) above, wherein the tie attachment device for feeding a tie to a reception space has a reception portion between said guiding member and said extruding member. 
         [0031]    (16) The tie attachment device according to (15) above, wherein a tie assembly is housed in said reception portion, wherein the tie assembly connects an inserting member inserted between both ends of a tie through a thin walled connecting portion, and the tie consists of a wire rod made of elastic material formed in an arc, the clearance between both ends is larger than the minimum width of the bound portion of material to be tied when both ends are opened within an elastic deformation range, and the maximum inner diameter in a restored state is smaller than the maximum width of the bound portion of material to be tied; and 
         [0032]    a biasing member is provided in said reception portion for biasing said tie assembly to the reception space. 
         [0033]    (17) The tie attachment device according to one of any (13) to (16) above, wherein said operating means has an operation lever provided slidably, and a connecting member provided slidably to said operation lever at the opposite side of supporting point of the operation lever, 
         [0034]    wherein an extruding rod has a extruding member fixed to its front end, and is inserted into a connecting hole formed on said connecting member, and moving the connecting member and the extruding rod as a unit by obliquely contacting the connection hole of the connecting member to the extruding rod when the operation lever is pulled. 
         [0035]    According to the invention described herein, when opening both ends within the elasticity distortion range the clearance between both ends are larger than the minimum width of a bound portion of the material to be tied, thereby material to be tied can be guided to inside by opening both ends, and bundling of the material to be tied can be tightened and fixed by the restoration strength of the wire rod because the maximum inner diameter in a restored state is smaller than the minimum width of the bound portion of the material to be tied. 
         [0036]    According to the invention described herein, the material(s) can be bound more securely by using the invention when binding a pair of materials to be tied. According to the invention described herein, providing an intersectional portion of crossed materials to be tied as the bound portion, the crossed materials to be tied can be bound in an intersectional state. According to the invention described herein, binding a plurality of material to be tied which are arranged in parallel and attaching these to the outside of the bound portion, thereby these can be tightened from outside and it is easy to bind them. 
         [0037]    According to the invention described herein, both ends of an arc wire rod have a curved portion curved opposite to the curving direction of the arc thereby it is easy to insert the inserting body between both ends of the arc wire rod and the work of opening both ends against the elastic force can easily be done. According to the invention described herein, the wire rod has a rupture portion to be ruptured when a deformation value exceeds the elasticity limit, thereby the arc wire rod can easily be ruptured by expanding and exceeding the elasticity limit and the work of removing a tie from the bound portion can easily be done. 
         [0038]    According to the invention described herein, when opening both ends of the arc wire rod, the rupture portion is located in a center portion, the position where stress is concentrated the most, thereby the tie can easily be ruptured and removed. According to the invention described herein, the rupture portion is a portion smaller in area of cross section compared to other portions, thereby the concentration of stress is further accelerated and the rupture operation can easily be done. According to the invention described herein, the rupture portion is a groove or a cut formed in a direction perpendicular to the axial direction of the wire rod, thereby the process of forming the rapture portion can be made easily. 
         [0039]    According to the invention described herein, the wire rod is in a shape that both ends intersect in a restoration state, thereby a large distortion amount can be taken when binding and the tightening force can further be increased. According to the invention described herein, because the wire rod has a loop when both end of the tie are expanded, the length of wire rod will be longer, distortion on the wire rod is equalized and reduced, and a distortion amount (the width of both ends expanded) can further be increased. Also, the contacting portion of the tie and materials to be tied can be increased, thereby further securely binding. 
         [0040]    According to the invention described herein, a plurality of ties can be carried as a unit by a tie assembly connecting inserting member inserted slidably between both ends of a tie through a thin walled connecting portion. Consequently, when attaching ties at a work site where a number of bound portions exist, work can be done by removing ties from the end in order, thereby working efficiency can be increased. According to the invention described herein, by operating the operation means to progress extruding member, the tie positioned in the reception space is pushed out forward. The tie is pushed open while progressing, and detached from the guiding member and attached to the materials to be tied when both ends of the tie are in a position exceeding the materials to be tied housed between the guiding member. By using such a device, attachment of the tie to materials to be tied can be made easily and quickly. 
         [0041]    According to the invention described herein, a groove is formed on an external face of the guiding member to guide both end portions of a tie, thus, the tie can be guided to the position exceeding the front end of the guiding member. According to the invention described herein, a storing portion is provided between the guiding member and the extruding member to feed the tie into the reception space, thereby the tie can easily be loaded to the tie attachment device. According to the invention described herein, the tie assembly is housed in a storing portion and the bias member is provided in the storing portion thereby the attachment operation of the tie can be made continuously without an operation of loading one tie at a time. This increases the efficiency of the binding work. 
         [0042]    According to the invention described herein, by sliding the operation lever, the connecting member extrudes the extruding member forward. When the connecting member moves forward, it contacts the connecting hole of the connecting member obliquely against the extruding rod, which further applies a force to move it forward, thereby the edge of the connecting hole is pressed by the extruding rod, which strengthens the connection of the extruding rod and the connecting member, and the extruding rod moves as a unit with the connecting member. Consequently, the extruding rod extrudes the extruding member and the tie is attached. The point for applying the force to slide the operation lever acts as a point of application and the connecting hole acts as a point of action. Further, adjusting the length of the operation lever generates a force to easily extrude the tie manually, and a simple and lightweight attachment device can be configured without driving equipment, such as motors. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0043]      FIG. 1  is an overall perspective view showing a tie. 
           [0044]      FIG. 2  is an overall plane view of a tie in a restored state. 
           [0045]      FIG. 3  is an enlarged perspective view of an inserting member. 
           [0046]      FIG. 4  is a side view showing a tie assembly. 
           [0047]      FIG. 5  is an overall perspective view of a tie attachment device. 
           [0048]      FIG. 6  is an overall side view of a tie attachment device. 
           [0049]      FIG. 7  is a perspective view showing a state when the tie is attached. 
           [0050]      FIG. 8  is an overall plane view showing a tie in another configuration. 
           [0051]      FIG. 9  is an overall plane view showing a tie in another configuration. 
           [0052]      FIG. 10  is a plane view of a tie showing a state of attachment to a bound portion. 
           [0053]      FIG. 11  is an overall plane view of another configuration example of a tie. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0054]    Detail of embodiments according to the present invention is hereinafter explained referring to the drawings.  FIG. 1  is an overall perspective view of a tie according to present invention, and  FIG. 2  is an overall plane view of a tie in a restored state. The tie  1  is configured by forming a wire rod  10  consisting of elastic material in a generally toric shape, and a metal spring material is used as an elastic material. In this embodiment, a cross section of the wire rod  10  is formed in a circular form and end portions alternately overlapping each other and forming a toric shape when in a non-deformed state (restored state) as shown in  FIG. 2 . 
         [0055]    Both end portions  11   a  and  11   b  of the wire rod  10  having curved portions  110   a  and  110   b  curved opposite to the curving direction of the wire rod  10 , and an inserting member  2  is inserted between the curved portions  110   a  and  110   b  in a loaded state as shown in  FIG. 1 . The inserting member  2  pushes open both ends of wire rod  10 , forming a clearance between the curved portions  110   a  and  110   b  while the wire rod  10  is in an elastic deformation state. Therefore, when the inserting member  2  is removed from the tie  1  with inserting member  2  inserted, a force to return to the restored state is acting. Also, a suppressed stress is consistently acting from the curved portions  110   a  and  110   b  in a direction to sandwich and attempt to crush the inserting member  2 . 
         [0056]      FIG. 3  is an enlarged perspective view of the inserting member  2 , and  FIG. 4  is a side view of the tie assembly  100 . The inserting member  2  is a plate form member having a thickness longer than the length of the wire rod  10  of tie  1 , and the side face of both ends contact the curved portions  110   a  and  110   b  are provided with depressed portions  21   a  and  21   b  having curvatures according to the curves of curved portions  110   a  and  110   b . Also, a groove  23  is formed in a circumferential direction on the side face of inserting member  2 , and both ends of the groove are connected to curved portion grooves  22   a  and  22   b  from in the depressed portions  21   a  and  21   b . The groove  23  and the curved portion grooves  22   a  and  22   b  are formed in a shape corresponding to the cross section shape of wire rod  10 . Also, the groove  23  is formed on a position closer to one of the upper face  211   a  or lower face  211   b  (one side) in the thickness direction of the inserting member  2 . 
         [0057]    When attached to the tie  1 , the groove  23  is formed on a side face  24 , the side of the tie  1  is positioned, and the side face  24  is formed in a convex along the curve of the tie  1 . Also, on a plane of the side where the groove  23  is formed, a fit portion  26  in a depressed shape that the rear end of a guiding member (described later) to be engaged, is formed. This fit portion  26  is formed to conform to the rear end portion of the guiding member, and in a shape that the width and the depth gradually decreases so that the opening portion is the deepest. Connecting portions  27   a  and  27   b  are provided to front end side end portions of the upper  211   a  and lower  211   b  faces of the inserting member  2 , and by these connecting portions  27   a  and  27   b , inserting members  2  layered in the thickness direction are alternately connected. The connecting portions  27   a  and  27   b  are specially formed as thin-walled, and configured to be able to be ruptured with a small shear stress. 
         [0058]    As shown in  FIG. 4 , a plurality of inserting members  2  are serially coupled by the connecting portions  27   a  and  27   b , and the ties  1  are attached to each inserting member. In this way, a tie assembly  100  is configured. The inserting portions  2  configured as above consist of, for example, a synthetic resin.  FIG. 5  is an overall perspective view of a tie attachment device  6 , and  FIG. 6  is an overall side view of the same. The tie attachment device  6  is provided with a guiding member  61  which guides the tie  1  so as to fit outside of the binding portion of the reinforcing bars while opening the tie  1 , a storing portion  62  positioned posterior to the guiding member  61  to store the tie  1 , an extruding member  63  positioned posterior to the storing portion  62 , an extruding rod  64  having the extruding member  63  fixed to its front end, a main body  65  to support the extruding rod  64  so as to move freely in an antero-posterior direction, an operation lever  66  slidably supported by the main body  65 , and a connecting member  67  having a connecting hole in which the operation lever  66  is inserted. 
         [0059]    The guiding member  61  has guiding portions  611   a  and  611   b  that respectively press curved portions  110   a  and  110   b  on both ends of the tie  1  from outside, the guiding portions  611   a  and  611   b  are connected to the rear end (back end) and configured to gradually increase the clearance of both towards the front end, and a storing portion  610  is formed between guiding portion  611   a  and  611   b . The guiding member  61  is fixed on a base material  60  protruding anterior to the main body  65 , and onto the base material  60 , a reception space  620  to be described later is provided between the main body  65  and the guiding member  61 . The intersectional portion (bound portion) of a vertical reinforcement Sr 1  and a horizontal reinforcement Sr 2  is housed in the storing portion  610 , and between the top ends of guiding portions  611   a  and  611   b  is an opening  612  for bringing the reinforcing bars into the storing portion  610 . 
         [0060]    Outer side faces of each guiding portion  611   a  and  611   b  are guiding faces that contact the curved portions  110   a  and  110   b  of tie  1  and guide in a way that twist around a reinforcing bar inside the storing portion  610  while pressing open the curved portions  110   a  and  110   b , and grooves  613   a  (not shown) and  613   b  formed to this guiding face along the axial direction of the guiding portions  611   a  and  611   b . One side (lower side in  FIG. 5 ) of grooves  613   a  (not shown) and  613   b  is formed higher and the other side (upper side in  FIG. 5 ) is formed lower, and configured to position the wire rod  10  main body of tie  1  to the side that is formed lower. 
         [0061]    The grooves  613   a  (not shown) and  613   b  are provided to the guiding portions  611   a  and  611   b  continuously from the rear end to the top end. In the back end portion of the guiding member  61 , the guiding portions  611   a  and  611   b  are integrated, with the height and width gradually decreasing towards the posterior, and the rear end is formed in an acute angle. To this rear end, the inserting member  2  of loaded tie  1  is layered, and the fit portion  26  of inserting member  2  is fitted to the rear end portion  615  of guiding member  61 . A reception space  620  is provided posterior to the guiding member  61  to house the tie  1 , further, the extruding member  63  is provided posterior to the reception space  620 . The extruding member  63  is formed in an arc along the curve of wire rod  10 , and a groove  631  (not shown) is formed to place the tie  1  inside. By this groove  631  (not shown), the tie  1  is prevented from separating from the extruding member  63 . 
         [0062]    Also, the curvature of extruding member  63  is formed to conform to the curvature of wire rod  10  when the tie  1  is pressed open to the maximum by the guiding member  61  as described later, instead of the curvature of tie  1  when housed inside the reception space  620 . The top end of extruding rod  64  is connected posterior to the extruding member  63 , and the extruding rod  64  supports the extruding member  62  so as to move freely in an antero-posterior direction The extruding member  63  contacts the main body  65 , and being slidably supported in an axial direction by this main body  65 . The main body  65  is provided with a front support portion  651  and a back support portion  652  that slidably support the extruding rod  64 , and a grip portion  656  projected in a direction almost perpendicular to the extruding rod  64 . 
         [0063]    The inserting hole to insert the extruding rod  64  formed on the front supporting portion  651  is formed sufficiently larger than the diameter of extruding rod  64 , and a play occurs between the inserting hole and the extruding rod  64 . A plate-shaped lock member  654  is provided posterior to the back supporting portion  652 . One end of the lock member  654  is slidably supported by the main body  65 , and inserting hole  654   a  is formed in center portion to insert the extruding rod  64 . A compression spring  655  is inserted between the other end of lock member  654  and the main body  65 . 
         [0064]    The lock member  654  is maintained by the compression spring  655  in a position against the extruding rod  64 . At this time, the edge of inserting hole  654   b  touches the side face of extruding rod  64  and maintains the extruding rod  64  to be incapable of sliding backwards, thereby locking the backward movement of extruding rod  64 . This lock is released by pressing in the lock member  65  against the compression spring  655  and positioning perpendicular to the extruding rod  64 , thereby the extruding rod  64  is in a state capable of moving backwards. 
         [0065]    The operation lever  66  is slidably supported pivotally at a supporting point  663  to the front side of grip portion  656 , and the handle portion  661  is configured to approach and depart to/from the grip portion  656 . The connecting member  664  is slidably supported pivotally to the end portion on the opposite side of the grip portion  661  centering on the supporting portion  663  through the supporting point  662 . In the center of connecting member  664 , a connecting hole  665  is formed to insert the extruding rod  64 , and the diameter of connecting hole  665  is formed to be slightly larger than that of extruding rod  64 . Also, the compression spring  653  is inserted between the connecting member  664  and front supporting portion  651  which biases the connecting member  651  in a posterior direction. 
         [0066]    In such configuration, the supporting point  664  is extruded forward when sliding the operation lever  66  to the grip portion  656 . By the movement of supporting point  664 , the connecting member  664  slants to the extruding rod  64 , thereby the edge of connecting hole  665  contacts the side face of extruding rod  64 . This contact increases a friction coefficient of the connecting hole  665  and extruding rod  64 , and the extruding rod  64  and connecting member  664  move forward as a unit against the biasing force of compression spring  653 . When returning the operation lever  66  to the original position, the connecting member  664  is in a position almost perpendicular to the extruding rod by the biasing force of compression spring  653 , thereby contacting the edge of the connecting hole  665  and the extruding rod  64  is released and only the connecting member  664  returns to the original position. Also, on the upper side of reception space  620 , reception portion  62  is provided to house a tie assembly  100 , the housed tie assembly  100  is pushed into the reception space  620  by the spring  621  as a biasing member provided between the inner wall of reception portion  62  and the feeding member  622 . 
         [0067]    In addition, a bursiform collecting portion  67  is provided on the lower side of storing portion  610  rear end, and having an opening on the storing portion  610  side. The collecting portion  67  receives inserting member  2  dropped from the reception portion  610  in its inside and collects them. In the tie assembly  100 , the tie  1  positioned undermost is positioned in the reception space  620 . The fit portion  26  of inserting member fits to the rear end portion  615  of guiding member  61  and the tie  1  in the reception space  620 . When the tie  1  inside the reception space  620  is extruded forward by the extruding member  63 , first, the curved portions  110   a  and  110   b  detach from the depressed portions  21   a  and  21   b  of inserting member  2 , and move into the grooves  613   a  and  613   b  provided on the guiding portions  611   a  and  611   b  of guiding member  61 . 
         [0068]    When the extruding member  63  is further extruded forward, the tie  1  progresses while the curved portions  110   a  and  110   b  are pressed open right and left by the guiding portions  611   a  and  611   b . Next, the rear end portion of wire rod  10  contacts the inserting member  2 , and the wire rod  10  fits within the groove  23  of inserting member  2 , thereby further extruding inserting member  2  forward. At this time, connecting portions  27   a  and  27   b  connected adjacent to inserting portion  2  in the tie assembly  100 , and the undermost inserting member  2  is detached from the tie assembly  100 . 
         [0069]    The detached inserting portion  2  moves along with tie  1 , drops downward as it reaches storing portion  610 , and is collected in the collecting portion  67 . Meanwhile, the bound portion which is an intersection of the horizontal reinforcement Sr 2  and the vertical reinforcement Sr 1 , is positioned within the storing portion  610 , and the curved portions  110   a  and  110   b  of tie  1  guided by the guiding member  61  so as to go around outside the bound portion. As the curved portions  110   a  and  100   b  of tie  1  reach the top end of guiding member  61 , the tie  1  detaches from the guiding member  61 , decreases its diameter by the restoration force of the wire rod  10 , and attaches to the bound portion which is an intersection of the vertical reinforcement Sr 1  and horizontal reinforcement Sr 2 , as shown in  FIG. 7 . 
         [0070]    The tie  1  is configured such that the inner diameter in the restored state as shown in  FIG. 2  is smaller than the sum of diameters of binding horizontal reinforcement Sr 2  and vertical reinforcement Sr 1 , and the distance between the curved portions  110   a  and  110   b  is larger than the sum of the diameters of binding horizontal reinforcement Sr 2  and vertical reinforcement Sr 1  when expanded within the elasticity limit of wire rod  10 . In addition, in order for the tie  1  to be able to be easily removed after the attachment, the tie  1  can be configured such that a groove or a cut is formed on the center portion, thereby it can easily be plastically deformed or ruptured at the groove or cut when deformed to exceed an elasticity limit. In this case, the rupture portion configured by forming a groove or a cut may be a site where the form of the wire rod  10  in the axial direction is discontinuous, or it may be a site where an area of cross section is smaller compared to other portions. Alternatively, it may be a site with a different composition. The site with different a composition can be provided by applying treatment different from other parts, such as quenching, annealing, or shot-peening. 
         [0071]      FIG. 8  is a plane view showing a tie  1 A having loop  12   a  formed on a center position of the wire rod  10 A. The loop  12 A is an annular section formed outside by curving the wire rod  10 A opposite to the main body portion formed in an arc. By providing the loop  12 A, distortion on the wire rod  10 A which occurs when opening both end portions  11   a  and  11   b , can be even equalized and decreased as a whole thereby a larger opening W of both end portions  11 Aa and  11 Ab can be realized. This enables use of a smaller wire rod. 
         [0072]    The tie  1 B shown in  FIG. 9  has a plurality of loops  14 B 1 - 14 B 5  at even intervals, and contacting portions  15 B 1 - 15 B 6  are provided in-between these loops  14 B 1 - 14 B 5 . For this tie  1 B, the clearance of both ends  11 Ba and  11 Bb can also be widened when deformed, and each contacting portion  15 B 1 - 15 B 6  can be in pressure contact against intersectional reinforcing bars as shown in  FIG. 10 , thereby increasing contacting portions against the reinforcing bars. This increases the binding strength of the bound portion. 
         [0073]      FIG. 11  is an overall plane view of another configuration example of a tie. A tie  1 C has a loop  12 C on the center of a wire rod, and wire rods  13 Ca and  13 Cb on both sides of the loop are formed in line symmetrical across a center line L which runs through the loop  12 C. That is, the wire rods  13 Ca and  13 Cb are formed by extending a pair of wire rods which is parallel in a same direction with reference to the loop  12 C as a base end, towards a direction away from the center line L, curving it to the direction of center line L at the curved portions  141 Ca and  141 Cb, and curving outward (direction away from the center line L) at the curved portions  143 Ca and  143 Cb on the top end side of curved portion  141 Ca and  141 Cb, further curving towards the center line L at the curved portion  142 Ca and  142 Cb on the top end side. The wire rods  13 Ca and  13 Cb are configured with an elastic material as the tie in the embodiments described above. Top end portions  11 Ca and  11 Cb of each wire rod  13 Ca and  13 Cb are curved outward and configured to slide and contact easily to the grooves  613   a  and  613   b  of guiding member  61 . As described above, in the tie  1 C, the wire rods  13 Ca and  13 Cb on left and right are in line asymmetry wave forms, thus reception retention portions  151  and  152  are formed between the wire rods  13 Ca and  13 Cb to house a horizontal reinforcement and a vertical reinforcement respectively. Each of the reception retention portions  151  and  152  according to this embodiment are in virtually rectangle forms and in the forms that retain horizontal reinforcement and vertical enforcement respectively, thereby increasing contact portions of the horizontal reinforcement and the vertical reinforcement with the wire rods  13 Ca and  13 Cb, which improves the retaining force. Also, the form of each reception retention portion  151  and  152  is not limited to a rectangle, and may be in other polygonal shapes or a circular shape.

Technology Classification (CPC): 4