Strapping machine

Abstract

FIELD: mechanical engineering.SUBSTANCE: strapping machine includes: a rotary shaft driven into rotation by an electric motor; a movable housing that moves in the axial direction of the rotary shaft in combination with the rotation of the rotary shaft and that rotates around the rotary shaft; an elastic housing that is compressed by moving the movable housing along the axial direction of the rotary shaft and that is configured to apply tension to a wire configured to tie an object to be tied by means of a stretching force; and a preventing element configured to prevent the formation of a force for twisting the elastic housing by means of rotation of the movable housing.EFFECT: improved performance.4 cl, 25 dwg

Description

Field of technology to which the invention relates

[0001] The present invention relates to a strapping machine that straps an object to be strapped, such as a reinforcing bar, using a wire.Background Art

[0002] Reinforcing bars are used in concrete structures to increase their strength, and are tied with wires so that the reinforcing bars do not deviate from a predetermined position when the concrete is poured.

[0003] In the prior art, a tying machine called a "rebar tying machine" is proposed that wraps a wire around two or more reinforcing bars and twists the wire wrapped around the reinforcing bars to tie two or more reinforcing bars with a wire.

[0004] When reinforcing bars are tied with wire, if the tying is loose, the reinforcing bars deviate from each other, requiring the reinforcing bars to be held tightly together. A technology is proposed in which a twisting block that twists the wire wound around the reinforcing bars is provided in such a way that it can approach or separate from the reinforcing bars. The twisting block is biased by a coil spring in the opposite direction, which is the direction away from the reinforcing bars, and the wire is twisted when tension is applied to the wire, thereby increasing the binding force (for example, see Japanese Patent No. 3013880).

[0005] Patent Document 1. Patent (Japan) No. 3013880

[0006] When the wire is twisted by the twisting block, the twisting force of the coil spring is generated. However, when the twisting force of the coil spring is generated relative to the coil spring, which applies tension to the wire through compression and extension, the wear resistance of the coil spring is reduced. Summary of the invention

[0007] The present invention is made to solve such a problem, and its object is to provide a strapping machine capable of preventing the formation of a force for twisting an elastic body that applies tension to a wire.

[0008] According to an aspect of the invention, a strapping machine is provided, including: a rotary shaft driven in rotation by an electric motor; a movable housing that moves in the axial direction of the rotary shaft in combination with the rotation of the rotary shaft and that rotates around the rotary shaft; an elastic housing that is compressed by moving the movable housing along the axial direction of the rotary shaft and that is configured to apply tension to a wire configured to tie an object to be tied by a stretching force; and a preventing member configured to prevent the formation of a force for twisting the elastic housing by rotating the movable housing.

[0009] According to an aspect of the invention, in a strapping machine that straps an object to be strapped, such as a reinforcing bar, using a wire, the generation of a twisting force by rotating a movable body on an elastic body compressed by moving the movable body along the axial direction of a rotation shaft is prevented.

[0010] According to an aspect of the invention, the wear resistance of the elastic body can be improved by preventing the generation of a force to twist the elastic body that exhibits the required function through compression and stretching.Brief description of the drawings

[0011] Fig. 1 is an internal configuration view when viewed from the side, illustrating an example of the overall configuration of the reinforcing bar binding machine according to the first embodiment. Fig. 2A is a partial side sectional view illustrating an example of the configuration of the main parts of the reinforcing bar binding machine according to the first embodiment. Fig. 2B is a perspective view illustrating an example of the configuration of the main parts of the reinforcing bar binding machine according to the first embodiment. Fig. 2C is a perspective view illustrating an example of the configuration of the main parts of the reinforcing bar binding machine according to the first embodiment. Fig. 3A is a side view illustrating the configuration of the main parts of the reinforcing bar binding machine according to the first embodiment. Fig.3B is a top view illustrating the configuration of the main parts of the reinforcing bar binding machine according to the first embodiment. Fig. 3C is a top sectional view illustrating the configuration of the main parts of the reinforcing bar binding machine according to the first embodiment. Fig. 4 is a top view illustrating an example of a preventing member. Fig. 5A is a sectional side view of the main parts illustrating an example of an operation of the reinforcing bar binding machine according to the first embodiment. Fig. 5B is a sectional side view of the main parts illustrating an example of an operation of the reinforcing bar binding machine according to the first embodiment. Fig. 5C is a sectional side view of the main parts illustrating an example of an operation of the reinforcing bar binding machine according to the first embodiment. Fig.5D is a sectional side view of the main parts illustrating an example of the operation of the reinforcing bar binding machine according to the first embodiment. Fig. 5E is a sectional side view of the main parts illustrating an example of the operation of the reinforcing bar binding machine according to the first embodiment. Fig. 5F is a sectional side view of the main parts illustrating an example of the operation of the reinforcing bar binding machine according to the first embodiment. Fig. 5G is a sectional side view of the main parts illustrating an example of the operation of the reinforcing bar binding machine according to the first embodiment. Fig. 5H is a sectional side view of the main parts illustrating an example of the operation of the reinforcing bar binding machine according to the first embodiment. Fig. 6 is a partial sectional side view illustrating an example of the configuration of the main parts of the reinforcing bar binding machine according to the second embodiment. Fig.7A is a sectional side view of the main parts illustrating an example of the operation of the reinforcing bar binding machine according to the second embodiment. Fig. 7B is a sectional side view of the main parts illustrating an example of the operation of the reinforcing bar binding machine according to the second embodiment. Fig. 7C is a sectional side view of the main parts illustrating an example of the operation of the reinforcing bar binding machine according to the second embodiment. Fig. 7D is a sectional side view of the main parts illustrating an example of the operation of the reinforcing bar binding machine according to the second embodiment. Fig. 7E is a sectional side view of the main parts illustrating an example of the operation of the reinforcing bar binding machine according to the second embodiment. Fig. 7F is a sectional side view of the main parts illustrating an example of the operation of the reinforcing bar binding machine according to the second embodiment. Fig.7G is a side sectional view of the main parts illustrating an example of the operation of the reinforcing bar binding machine according to the second embodiment. Fig. 7H is a side sectional view of the main parts illustrating an example of the operation of the reinforcing bar binding machine according to the second embodiment. Detailed description of the embodiments.

[0012] Hereinafter, an example of a reinforcing bar binding machine according to an embodiment of the binding machine of the present invention will be described herein with reference to the drawings.

[0013] Configuration Example of the Rebar Binding Machine According to the First EmbodimentFig. 1 is an internal configuration view when viewed from the side, illustrating an example of the overall configuration of the rebar binding machine according to the first embodiment.Fig. 2A is a partial side sectional view illustrating an example of the configuration of the main parts of the rebar binding machine according to the first embodiment.Figs. 2B and 2C are perspective views illustrating configuration examples of the main parts of the rebar binding machine according to the first embodiment.

[0014] The reinforcing bar binding machine 1A is held and used by a worker and includes a main body section 10A and a handle section 11A. In addition, the reinforcing bar binding machine 1A feeds a wire W in a forward direction indicated by an arrow F, wraps the wire W around the reinforcing bars S, which are an object to be bound, feeds the wire W wrapped around the reinforcing bars S in a reverse direction indicated by an arrow R, wraps the wire W around the reinforcing bars S, and then twists the wire W to bind the reinforcing bars S with the wire W.

[0015] In order to realize the above function, the reinforcing bar binding machine 1A includes a magazine 2A that houses the W wire, a wire feeding unit 3A that feeds the W wire, and a wire guide 4A that guides the W wire fed to the wire feeding unit 3A. The reinforcing bar binding machine 1A further includes a bend forming unit 5A that forms a path for winding the wire W fed by the wire feeding unit 3A around the reinforcing bars S, and a cutting unit 6A that cuts the wire W wound around the reinforcing bars S. In addition, the reinforcing bar binding machine 1A includes a binding unit 7A for twisting the wire W wound around the reinforcing bars S, and an actuating unit 8A that actuates the binding unit 7A.

[0016] Magazine 2A is an example of a placing unit, and a bobbin 20, around which a long wire W is wound in such a way that it is fed outward, is placed in the magazine 2A in a rotatably and removable manner. As the wire W, a wire formed from a metal wire that allows plastic deformation, a wire in which the metal wire is coated with resin, or a multi-strand wire is used. In the bobbin 20, one or more wires W are wound around a hub section (not illustrated) in such a manner that one or more wires W can be pulled out from the bobbin 20 simultaneously.

[0017] The wire feeding unit 3A includes a pair of feed gears 30, which are positioned in the middle and feed one or a plurality of wires W, arranged in parallel. In the wire feeding unit 3A, the rotation operation of the feed motor (not illustrated) is transmitted to rotate the feed gears 30. Accordingly, the wire feeding unit 3A feeds the wire W, positioned in the middle between the pair of feed gears 30, along the drawing direction of the wire W. In a configuration in which a plurality of wires W, for example, 2 wires W are fed, the 2 wires W are fed in parallel.

[0018] In the wire feed unit 3A, the rotation direction of the feed gears 30 is switched by switching the forward and reverse rotation directions of the feed motor (not illustrated), and the forward and reverse directions of the wire feed W are switched.

[0019] The wire guide 4A is disposed above the feed gears 30 in the feed direction of the wire W fed in a forward direction. In the configuration in which the reinforcing bar binding machine 1A binds the reinforcing bar with two wires W, the wire guide 4A guides the two wires W that enter between the pair of feed gears 30 by arranging the two wires W in parallel along the arranging direction of the pair of feed gears 30.

[0020] In the wire guide 4A, the hole on the upstream side in the feeding direction of the wire W fed forward has a larger opening area than the hole on the downstream side, and part or all of the inner surface of the hole is wedge-shaped. Accordingly, the insertion of the wire W drawn from the spool 20 accommodated in the magazine 2A into the wire guide 4A can be easily performed.

[0021] The bending forming unit 5A includes a bending guide 50 that bends the wire W fed by the wire feeding unit 3A, and a driving guide 51 that guides the wire W bent by the bending guide 50 into the binding unit 7A. In the reinforcing bar binding machine 1A, since the path of the wire W fed by the wire feeding unit 3A is adjusted by the bending forming unit 5A, the path of the wire W is a loop Ru, as illustrated by the dotted line with two dots in Fig. 1, and the wire W is wound around the reinforcing bars S.

[0022] The cutting unit 6A includes a fixed blade unit 60, a movable blade unit 61 that cuts the wire W together with the fixed blade unit 60, and a transmission mechanism 62 that transmits the operation of the binding unit 7A to the movable blade unit 61. The cutting unit 6A cuts the wire W by rotating the movable blade unit 61 with the fixed blade unit 60 as an axis around a fulcrum. The transmission mechanism 62 includes a first rod 62b, which rotates with a shaft 62a as a support point, and a second rod 62c, which connects the first rod 62b and the movable blade block 61, and the rotation operation of the first rod 62b is transmitted to the movable blade block 61 through the second rod 62c.

[0023] The binding unit 7A includes a wire locking housing 70 to which the wire W is locked. A detailed embodiment of the binding unit 7A is described below. The drive unit 8A includes an electric motor 80 and a gear reducer 81, which performs deceleration and torque amplification.

[0024] The reinforcing bar binding machine 1A includes a feed control unit 90, to which the distal end of the wire W in the wire feed path, locked by the wire locking body 70, is adjacent. In the reinforcing bar binding machine 1A, the bending guide 50 and the advancing guide 51 of the bend forming unit 5A described above are provided at the front side end portion of the section 10A of the main body. In addition, in the reinforcing bar binding machine 1A, the adjoining unit 91, to which the reinforcing bars S are adjacent, is provided between the bending guide 50 and the advancing guide 51 at the front side end portion of the section 10A of the main body.

[0025] In the 1A rebar binding machine, the 11A handle section extends downward from the 10A section of the main body. In addition, a 15A battery is detachably connected to the lower section of the 11A handle. In the 1A rebar binding machine, a 2A magazine is provided in front of the 11A handle section. In the 1A rebar binding machine, the 3A wire feeding unit, the 6A cutting unit, the 7A binding unit, the 8A driving unit that drives the 7A binding unit, etc., described above, are housed in the 10A section of the main body.

[0026] In the reinforcing bar binding machine 1A, the trigger 12A is provided on the front side of the handle section 11A, and the switch 13A is provided inside the handle section 11A. In the reinforcing bar binding machine 1A, the control unit 14A controls the electric motor 80 and the feed motor (not illustrated) according to the state of the switch 13A pressed by pressing the trigger 12A.

[0027] Fig. 3A is a side view illustrating the configuration of the main parts of the reinforcing bar binding machine according to the first embodiment. Fig. 3B is a top view illustrating the configuration of the main parts of the reinforcing bar binding machine according to the first embodiment. Fig. 3C is a top sectional view illustrating the configuration of the main parts of the reinforcing bar binding machine according to the first embodiment. Next, the details of the binding unit 7A and the connecting structure between the binding unit 7A and the driving unit 8A will be described with reference to the drawings.

[0028] The binding unit 7A includes a wire-stopping housing 70, which is used to stop the wire W, and a rotary shaft 72, which controls the wire-stopping housing 70. In the binding unit 7A and the driving unit 8A, the rotary shaft 72 and the electric motor 80 are connected to each other via a gear reducer 81, and the rotary shaft 72 is driven by the electric motor 80 via the gear reducer 81.

[0029] The wire stopper body 70 includes a central hook 70C connected to a rotary shaft 72, a first side hook 70L and a second side hook 70R that open and close relative to the central hook 70C, and a sleeve 71 that controls the first side hook 70L and the second side hook 70R in combination with the rotation operation of the rotary shaft 72.

[0030] In the strapping unit 7A, the side on which the central hook 70C, the first side hook 70L, and the second side hook 70R are provided is called the "front side", and the side on which the rotary shaft 72 is connected to the reducer 81 is called the "rear side".

[0031] The central hook 70C is connected to the rotation shaft 72 in such a way that it is rotatable relative to the rotation shaft 72 at a front end, which is one end portion of the rotation shaft 72, and is movable in the axial direction as a single unit with the rotation shaft 72.

[0032] The far end side of the first side hook 70L, which is one end portion of the first side hook 70L along the axial direction of the rotational shaft 72, is positioned on one side relative to the central hook 70C. The rear end side of the first side hook 70L, which is the other end portion of the first side hook 70L along the axial direction of the rotational shaft 72, is rotatably supported by the central hook 70C via the shaft 71b.

[0033] The distal end side of the second side hook 70R, which is one end portion of the second side hook 70R along the axial direction of the rotational shaft 72, is positioned on the other side relative to the central hook 70C. The rear end side of the second side hook 70R, which is the other end portion of the second side hook 70R along the axial direction of the rotational shaft 72, is rotatably supported by the central hook 70C via the shaft 71b.

[0034] Accordingly, the wire stopper housing 70 opens and closes in a direction in which the distal end side of the first side hook 70L is separated from and brought into contact with the central hook 70C through a rotating operation with the shaft 71b as a fulcrum. In addition, the wire stopper housing 70 opens and closes in a direction in which the distal end side of the second side hook 70R is separated from and brought into contact with the central hook 70C.

[0035] The rear end of the rotation shaft 72, which is the other end portion of the rotation shaft 72, is connected to the reduction gear 81 through a connection block 72b, which is configured to rotate integrally with the reduction gear 81 and be movable in the axial direction relative to the reduction gear 81. The connection block 72b includes a spring 72c, which biases the rotation shaft 72 backward, which is a direction approaching the reduction gear 81, and adjusts the position of the rotation shaft 72 along the axial direction. Accordingly, the rotation shaft 72 can move forward, which is a direction away from the reduction gear 81, when receiving a force with a rearward push by the spring 72c. Accordingly, when a force for moving the wire stopper housing 70 forward along the axial direction is applied, the rotation shaft 72 is movable forward when receiving a force with a rearward push by the spring 72c.

[0036] The sleeve 71 has a shape in which a range of a predetermined length along the axial direction of the rotation shaft 72 from the end portion in the forward direction indicated by the arrow A1 is divided into two ranges in the radial direction, and the first side hook 70L and the second side hook 70R are inserted into the sleeve 71. In addition, the sleeve 71 has a tubular shape covering the periphery of the rotation shaft 72 and has a protrusion (not illustrated) protruding from the inner peripheral surface of the tubular space into which the rotation shaft 72 is inserted. The protrusion enters a portion of the groove of the feed screw 72a formed along the axial direction on the outer periphery of the rotation shaft 72.The sleeve 71 is an example of a movable housing, and when the rotation shaft 72 rotates, the sleeve 71 moves in a front-to-back direction, which is a direction along the axial direction of the rotation shaft 72, according to the rotation direction of the rotation shaft 72 by means of an extrusion action (not illustrated) and a feed screw 72a of the rotation shaft 72. The sleeve 71 rotates as a single unit with the rotation shaft 72 around the rotation shaft 72.

[0037] The sleeve 71 includes an opening and closing pin 71a that opens and closes the first side hook 70L and the second side hook 70R.

[0038] The opening and closing pin 71a is inserted into the opening and closing guide cavity 73 provided in the first side hook 70L and the second side hook 70R. The opening and closing guide cavity 73 extends along the moving direction of the sleeve 71 and has a shape to convert the linear movement of the opening and closing pin 71a, moving in combination with the sleeve 71, into an opening and closing operation by rotating the first side hook 70L and the second side hook 70R using the shaft 71b as a fulcrum.

[0039] In the wire stopper body 70, when the sleeve 71 moves in the reverse direction indicated by the arrow A2, the first side hook 70L and the second side hook 70R move in the direction from the central hook 70C by a rotation operation with the shaft 71b as a fulcrum, according to the trajectory of the opening and closing pin 71a and the shape of the opening and closing guide cavity 73.

[0040] Accordingly, the first side hook 70L and the second side hook 70R are opened relative to the center hook 70C, and a feeding path through which the wire W passes is formed between the first side hook 70L and the center hook 70C and between the second side hook 70R and the center hook 7C.

[0041] In the state in which the first side hook 70L and the second side hook 70R are open with respect to the central hook 70C, the wire W fed by the wire feeding unit 3A passes between the central hook 70C and the first side hook 70L. The wire W passing between the central hook 70C and the first side hook 70L is guided into the bend forming unit 5A. After that, the wire W bent by the bend forming unit 5A and guided into the binding unit 7A passes between the central hook 70C and the second side hook 70R.

[0042] In the wire locking body 70, when the sleeve 71 moves in the forward direction indicated by the arrow A1, the first side hook 70L and the second side hook 70R move in a direction approaching the central hook 70C by a rotating operation with the shaft 71b as a fulcrum according to the trajectory of the opening and closing pin 71a and the shape of the opening and closing guide cavity 73. Accordingly, the first side hook 70L and the second side hook 70R close relative to the central hook 70C.

[0043] When the first side hook 70L closes relative to the center hook 70C, the wire W, which is placed in the middle between the first side hook 70L and the center hook 70C, is stopped in a shape moved between the first side hook 70L and the center hook 70C. In addition, when the second side hook 70R closes relative to the center hook 70C, the wire W, which is placed in the middle between the second side hook 70R and the center hook 70C, is stopped in such a way that it is not torn off due to the second side hook 70R and the center hook 70C.

[0044] The wire stopper body 70 includes a bending block 71c1 that gives the wire W a predetermined shape by pressing and bending the distal end side of the wire W, which is one end portion of the wire W, in a predetermined direction, and a bending block 71c2 that gives the wire W a predetermined shape by pressing and bending the tail end side of the wire W, which is the other end portion of the wire W cut by the cutting block 6A, in a predetermined direction. In the present example, the bending block 71c1 and the bending block 71c2 are formed in the end portion of the sleeve 71 in the forward direction indicated by the arrow A1.

[0045] When the sleeve 71 moves in the forward direction indicated by the arrow A1, the far end side of the wire W, which is locked by the central hook 70C and the second side hook 70R, is pressed by the bending block 71c1 and is bent toward the side of the reinforcing bar S. In addition, when the sleeve 71 moves in the forward direction indicated by the arrow A1, the tail end side of the wire W, which is locked by the central hook 70C and the first side hook 70L and is cut by the cutting block 6A, is pressed by the bending block 71c2 and is bent toward the side of the reinforcing bar S.

[0046] The binding unit 7A includes a rotation control unit 74 that controls the rotation of the wire locking body 70 and the sleeve 71 in combination with the rotation operation of the rotation shaft 72. The rotation control unit 74 includes a rotation control blade 74a provided on the sleeve 71 and a rotation control latch 74b provided on the main body portion 10A.

[0047] The rotation regulating blade 74a is realized by providing, at predetermined intervals in the peripheral direction of the sleeve 71, a plurality of protrusions protruding in the radial direction from the outer periphery of the sleeve 71. The rotation regulating blade 74a is attached to the sleeve 71 and moves and rotates as a single unit with the sleeve 71.

[0048] In the rotation regulating unit 74, the rotation regulating blade 74a is locked to the rotation regulating latch 74b in an operating range in which the wire W is locked by the wire locking body 70, the wire W is wound around the reinforcing bars S and then cut, and the wire W is bent and formed by the bending units 71c1 and 71c2 of the sleeve 71. When the rotation regulating blade 74a is locked to the rotation regulating latch 74b, the rotation of the sleeve 71 is adjusted in combination with the rotation of the rotation shaft 72, and the sleeve 71 is moved in the front-to-back direction by the rotation operation of the rotation shaft 72.

[0049] Additionally, in the working range in which the wire W locked by the wire locking body 70 is twisted, the locking of the rotation regulating blade 74a to the rotation regulating latch 74b of the rotation regulating unit 74 is stopped. When the locking of the rotation regulating blade 74a to the rotation regulating latch 74b is stopped, the sleeve 71 rotates in combination with the rotation of the rotation shaft 72. In the wire locking body 70, the central hook 70C, the first side hook 70L and the second side hook 70R, which lock the wire W, rotate in combination with the rotation of the sleeve 71.

[0050] In the working range of the sleeve 71 and the wire stopper body 70 along the axial direction of the rotation shaft 72, the working range in which the wire W is stopped by the wire stopper body 70 is called the "first working range." The working range in which the wire W stopped by the wire stopper body 70 is cut by the cutting unit 6A is called the "second working range." The working range in which the wire W cut by the cutting unit 6A is bent and formed by the bending units 71c1 and 71c2 of the sleeve 71 is called the "third working range." In addition, the working range in which the wire W is twisted is called the "fourth working range."

[0051] The strapping block 7A is provided such that the transmission member 83 is movable in combination with the sleeve 71. The transmission member 83 is rotatably connected to the sleeve 71 and moves in the front-to-back direction in combination with the sleeve 71 without interlocking with the rotation of the sleeve 71.

[0052] The transmission member 83 includes an engaging block 83a that engages with the first link 62b of the transmission mechanism 62. When the transmission member 83 moves in the front-to-back direction in combination with the sleeve 71, the engaging block 83a of the binding block 7A engages with the first link 62b to rotate the first link 62b. The transmission mechanism 62 transmits the rotation operation of the first link 62b to the movable blade block 61 through the second link 62c to rotate the movable blade block 61. Accordingly, through the operation in which the sleeve 71 moves in the forward direction, the movable blade block 61 rotates in a predetermined direction, and the wire W is cut.

[0053] The binding unit 7A includes a tension application spring 92 that performs binding in a state in which tension is applied to the wire W. The tension application spring 92 is an example of an elastic body and biases the sleeve 71 and the wire locking body 70 in a direction from the adjacent unit 91 along the axial direction of the rotation shaft 72. The tension application spring 92 is realized, for example, by a coil spring that is stretched and compressed in the axial direction and is installed on the outer periphery of the sleeve 71 between the rotation regulating blade 74a and the support member 76d that supports the sleeve 71 such that it is rotating and sliding in the axial direction. When the tension spring 92 is realized by means of a coil spring, the inner diameter of the tension spring 92 is larger than the outer diameter of the sleeve 71.

[0054] When the sleeve 71 moves in the forward direction indicated by the arrow A1 along the axial direction of the rotational shaft 72, the tension spring 92 is compressed between the support member 76d and the blade 74a to regulate the rotation. The compressed tension spring 92 displaces, by means of a stretching force, the sleeve 71 in the opposite direction indicated by the arrow A2, which is the direction from the adjacent block 91 along the axial direction of the rotational shaft 72.

[0055] Accordingly, the tension application spring 92 biases the sleeve 71 and the wire stopper body 70 including the sleeve 71 in a direction in which the tension applied to the wire W wound around the reinforcing bars S is maintained, and applies tension to the wire W, which is cut by the cutting unit 6A after being wound around the reinforcing bars S, with a force greater than the force applied in the direction in which the wire W wound around the reinforcing bars S is loosened.

[0056] In other words, the reaction force of the tension applied to the wire W by the operation of winding the wire W around the reinforcing bars S is applied to the wire stopper body 70 stopping the wire W, thereby applying a force to move the wire stopper body 70 in a forward direction along the axial direction of the rotation shaft 72 to the wire stopper body 70. The wire stopper body 70 is movable in a forward direction together with the rotation shaft 72 while receiving the force to push the rotation shaft 72 in the opposite direction along the axial direction by the spring 72c. Therefore, when the wire stopper body 70 stopping the wire W moves in a forward direction along the axial direction of the rotation shaft 72, the wire W wound around the reinforcing bars S is loosened.

[0057] On the contrary, the wire stopper body 70 receives a force to push the sleeve 71 in the reverse direction by means of a force to stretch the compressed spring 92 for applying tension. The force to stretch the compressed spring 92 for applying tension is greater than the force to move the wire stopper body 70 in the forward direction by means of the reaction force of the tension applied to the wire W wrapped around the reinforcing bars S, and the wire stopper body 70 is prevented from moving in the forward direction. Accordingly, the binding is performed in a state in which tension is applied to the wire W.

[0058] Fig. 4 is a plan view illustrating an example of a preventing member, and the configuration for preventing the generation of a force for torsion of the spring 92 for applying tension is described below with reference to the drawings. The reinforcing bar tying machine 1A includes a preventing member 93 that prevents the generation of a force for torsion of the spring 92 for applying tension.

[0059] The preventing member 93 has a plate shape and has a hollow section 93a having a diameter slightly larger than the diameter of the section of the sleeve 71, through which the tension application spring 92 passes so that it penetrates the preventing member 93. The preventing member 93 is provided between the tension application spring 92 and the rotation regulating blade 74a by passing the sleeve 71 between the tension application spring 92 and the rotation regulating blade 74a through the hollow section 93a. In addition, the preventing member 93 is rotatably supported relative to the sleeve 71 between the tension application spring 92 and the rotation regulating blade 74a and is movably supported in the axial direction of the rotation shaft 72 relative to the sleeve 71.

[0060] The preventing member 93 includes a rotation preventing block 93b that is engaged with the arm section 63. The arm section 63 has a plate shape and extends in a front-to-back direction, which is the moving direction of the sleeve 71 indicated by arrows A1 and A2. The side of the arm section 63 facing the sleeve 71 is parallel to the axial direction of the rotation shaft 72. In the present example, the arm section 63 is provided to connect the cutting unit 6A to the main body section 10A, and the fixed blade unit 60 and the shaft 62a are connected to the arm section 63. The movable blade unit 61 is rotatably supported by the fixed blade unit 60, and the first link 62b is rotatably supported by the shaft 62a.

[0061] The rotation preventing block 93b is realized by a groove opened with a width slightly larger than the plate thickness of the arm portion 63, and when the preventing member 93 is supported by the sleeve 71, the rotation preventing block 93b is engaged with the arm portion 63 in a state in which the arm portion 63 is inserted into the groove.

[0062] Accordingly, the preventing member 93 is supported so as to be movable in the front-to-back direction along the axial direction of the rotation shaft 72 relative to the sleeve 71 in a state in which rotation according to the rotation of the sleeve 71 and the rotation-regulating blade 74a is prevented, and moves in the front-to-back direction in combination with the movement of the sleeve 71 and the rotation-regulating blade 74a in the front-to-back direction.

[0063] When the sleeve 71 moves in the forward direction indicated by the arrow A1, the preventing member 93 is pressed by the rotational control blade 74a and moves in a direction approaching the supporting member 76d while receiving a force pressing against the rotational control blade 74a by the tension application spring 92. When the sleeve 71 rotates, the preventing member 93 is pressed by the rotational control blade 74a and receives a force in the rotational direction while receiving a force pressing against the rotational control blade 74a by the tension application spring 92.

[0064] However, since the rotation preventing block 93b is engaged with the shoulder portion 63, the preventing member 93 moves in a direction approaching the support member 76d in a state in which rotation according to the rotation of the sleeve 71 and the rotation regulating blade 74a is prevented.

[0065] The front end side, which is one end portion of the tension application spring 92, faces the support member 76d. At least a part of the support member 76d includes a section that does not rotate relative to the main body section 10A, and the front end side of the tension application spring 92 is pressed against the section that does not rotate relative to the main body section 10A in the support member 76d. In the present example, the support member 76d is realized by a bearing having a single-piece structure and is installed in the main body section 10A. The entire support member 76d does not rotate relative to the main body section 10A.

[0066] The rear end side, which is the other end portion of the tension application spring 92, faces the preventing member 93. The rear end side of the tension application spring 92 is pressed against the preventing member 93. At least a portion of the preventing member 93, which is pressed by the tension application spring 92, is prevented from rotating according to the rotation of the sleeve 71. In the present example, as described above, the entire preventing member 93 does not rotate relative to the main body portion 10A, and rotation according to the rotation of the sleeve 71 is prevented.

[0067] Example of Operation of Rebar Binding Machine According to the Present Embodiment Figs. 5A, 5B, 5C, 5D, 5E, 5F, 5G and 5H are side sectional views of main parts illustrating examples of operations of the rebar binding machine according to the first embodiment. Fig. 5A shows a state in which the rebars S are arranged in a position in which they can be tied. Fig. 5B illustrates an operation of feeding the wire W in a forward direction and winding the wire W around the rebars S. Fig. 5C illustrates an operation of stopping the wire W wound around the rebars S. Fig. 5D illustrates an operation of feeding the wire W in a reverse direction and winding the wire W around the rebars S. Fig. 5E illustrates the operation of cutting off the excess portion of wire W wound around reinforcing bars S. Fig. 5F illustrates the operation of bending wire W wound around reinforcing bars S. Fig.5G and 5H illustrate the twisting operation of wire W wrapped around reinforcing bars S.

[0068] The following describes the operation of tying reinforcing bars S using wire W by means of a reinforcing bar tying machine 1A according to the first embodiment with reference to the drawings.

[0069] In the reinforcing bar binding machine 1A, the state in which the wire W is held between the pair of feed gears 30, and the distal end of the wire W is located between the holding position of the feed gears 30 and the fixed blade block 60 of the cutting unit 6A, is a ready state. In the reinforcing bar binding machine 1A, in the ready state, the sleeve 71 and the wire locking body 70, in which the first side hook 70L, the second side hook 70R and the central hook 70C are attached to the sleeve 71, move in the reverse direction indicated by the arrow A2, and as illustrated in Fig. 3B, etc., the first side hook 70L opens relative to the central hook 70C, and the second side hook 70R opens relative to the central hook 70C.In addition, in the reinforcing bar binding machine 1A, in the standby state, the rotation control blade 74a is separated from the tension application spring 92, and the sleeve 71 and the wire stopper body 70 are not moved backward by the tension application spring 92.

[0070] As illustrated in Fig. 5A, reinforcing bars S are inserted between the bending guide 50 and the advancing guide 51 of the bend forming unit 5A. When the trigger 12A is pressed, the feeding motor (not illustrated) is driven in the forward rotation direction, and, as illustrated in Fig. 5B, the wire W is fed in the forward direction indicated by the arrow F by the wire feeding unit 3A.

[0071] When a plurality of, for example, 2 W wires are fed, the 2 W wires are fed by the wire guide 4A in a state of being arranged in parallel along the axial direction of the loop Ru formed by the W wires.

[0072] The wire W, fed in a forward direction, passes between the central hook 70C and the first side hook 70L and is fed into the bending guide 50 of the bend forming unit 5A. The wire W is wrapped around the reinforcing bars S by passing through the bending guide 50.

[0073] The wire W wound by the bending guide 50 is guided by the advancing guide 51 and further fed in a forward direction by the wire feeding unit 3A and then guided between the central hook 70C and the second side hook 70R by the advancing guide 51. After this, the wire W is fed until its distal end is adjacent to the feeding control unit 90. When the distal end of the wire W is fed to a position in which the distal end of the wire W is adjacent to the feeding control unit 90, the driving of the feeding motor (not illustrated) is stopped.

[0074] After the wire W is fed forward, the electric motor 80 is driven in the forward rotation direction. For the sleeve 71, in the first operating range in which the wire W is stopped by the wire stopping body 70, the rotation of the sleeve 71 in combination with the rotation of the rotation shaft 72 is controlled by locking the rotation control blade 74a to the rotation control latch 74b. Accordingly, as illustrated in Fig. 5C, the rotation of the electric motor 80 is converted into a linear movement, and the sleeve 71 moves in the direction shown by arrow A1, which is the forward direction.

[0075] When the sleeve 71 moves in a forward direction, the opening and closing pin 71a passes through the opening and closing guide cavity 73. Accordingly, the first side hook 70L moves in a direction approaching the central hook 70C through a rotating operation with the shaft 71b as a fulcrum. When the first side hook 70L closes relative to the central hook 70C, the wire W, which is positioned midway between the first side hook 70L and the central hook 70C, is locked in a shape moved between the first side hook 70L and the central hook 70C.

[0076] Additionally, the second side hook 70R moves in a direction approaching the central hook 70C through a rotating operation with the shaft 71b as a fulcrum. When the second side hook 70R closes relative to the central hook 70C, the wire W, located midway between the second side hook 70R and the central hook 70C, is stopped so that it is not torn off by the second side hook 70R and the central hook 70C.In the reinforcing bar binding machine 1A, in the first operating range in which the wire W is stopped by the wire stopping body 70, the sleeve 71 and the wire stopping body 70 are not moved backward by the tension applying spring 92, and an additional load due to the tension applying spring 92 is not applied by an operation in which the sleeve 71 and the wire stopping body 70 are moved in the direction shown by the arrow A1, which is a straight direction.

[0077] After the sleeve 71 moves forward to a position in which the wire W is stopped by the closing operation of the first side hook 70L and the second side hook 70R, the rotation of the motor 80 is temporarily stopped, and the feeding motor (not illustrated) is driven in the reverse rotation direction.

[0078] Accordingly, the pair of feed gears 30 rotate in the reverse direction, and, as illustrated in Fig. 5D, the wire W held between the pair of feed gears 30 is fed in the reverse direction indicated by the arrow R. Since the far end side of the wire W is stopped so that it does not come off between the second side hook 70R and the central hook 70C, the wire W is wound around the reinforcing bars S by the operation of feeding the wire W in the reverse direction.

[0079] After the wire W is wrapped around the reinforcing bars S and the driving of the feeding motor 31 in the reverse rotation direction is stopped, the motor 80 is driven in the forward rotation direction to further move the sleeve 71 in the forward direction indicated by the arrow A1. As illustrated in Fig. 5E, the operation in which the sleeve 71 moves in the forward direction is transmitted to the cutting unit 6A by the transmission mechanism 62, and then the movable blade unit 61 rotates. The wire W, locked by the first side hook 70L and the central hook 70C, is cut by the operations of the fixed blade unit 60 and the movable blade unit 61.In the reinforcing bar binding machine 1A, in the second working range in which the sleeve 71 and the wire stopper body 70 move in the forward direction to cut the wire W, the rotation regulating blade 74a comes into contact with the tension applying spring 92 through the preventing member 93, the tension applying spring 92 is compressed between the support member 76d and the rotation regulating blade 74a, and the sleeve 71 and the wire stopper body 70 are moved backward by the tension applying spring 92.

[0080] When the wire W is cut, the load applied to the movable blade unit 61 disappears. The movable blade unit 61 is connected to the sleeve 71 through the second link 62c and the first link 62b of the transmission mechanism 62 and the transmission member 83. Accordingly, when the load applied to the movable blade unit 61 disappears, the force for regulating the movement of the sleeve 71 is reduced by the load applied to the movable blade unit 61.

[0081] In the operation of winding the wire W around the reinforcing bars S described above, since the far end side of the wire W is stopped in such a way that it is not torn off between the second side hook 70R and the central hook 70C, the tension applied to the wire W increases. Accordingly, the force for moving the sleeve 71 in a forward direction is applied to the sleeve 71 by the reaction force of the tension applied to the wire W. Therefore, when the wire W is cut and the load applied to the movable blade block 61 disappears, and the force for regulating the movement of the sleeve 71 is reduced by the load applied to the movable blade block 61, the sleeve 71 moves in a forward direction.

[0082] When the sleeve 71 moves in the forward direction, the force for pulling the wire W, which is stopped by the wire stopping body 70, in which the central hook 70C, the first side hook 70L and the second side hook 70R are attached to the sleeve 71, in the reverse direction decreases, and the wire W wrapped around the reinforcing bars S is loosened before twisting.

[0083] On the contrary, in the present embodiment, in the second operating range in which the wire W is cut, the sleeve 71 is shifted in the backward direction by the tension application spring 92 compressed between the support member 76d and the rotation control blade 74a, through an operation in which the sleeve 71 is moved in the forward direction. Since the compressed tension application spring 92 is stretched, the force for shifting the sleeve 71 backward is greater than the reaction force of the tension applied to the wire W by wrapping around the reinforcing bars S. Therefore, even when the wire W is cut and the load applied to the movable blade unit 61 disappears, and the force for regulating the movement of the sleeve 71 is reduced by the load applied to the movable blade unit 61, the sleeve 71 is prevented from moving in the forward direction.

[0084] By preventing the sleeve 71 from moving forward, the force for pulling the wire W locked by the wire locking body 70 is prevented from decreasing. Accordingly, the tension applied to the wire W is maintained by the operation of feeding the wire W in the reverse direction and winding the wire W around the reinforcing bars S, and the wire W wound around the reinforcing bars S is prevented from loosening before twisting. The tension application spring 92 has a configuration in which a coil spring is provided on the outer periphery of the sleeve 71, and therefore, the limitation of the diameter and the like of the spring is small, and the bias force can be improved.

[0085] As described above, in the reinforcing bar binding machine 1A, in the second working range in which the wire W is cut, the sleeve 71 and the wire stopper body 70 are shifted in the backward direction by the tension applying spring 92, and therefore, the forward movement of the sleeve 71 can be prevented. On the other hand, when the sleeve 71 and the wire stopper body 70 are shifted backward by the tension applying spring 92 in the first working range in which the wire W is stopped by the wire stopper body 70, the additional load applied to the electric motor 80 increases.

[0086] As described above, in the reinforcing bar binding machine 1A, the rotation regulating blade 74a is separated from the tension application spring 92 in the standby state, and the sleeve 71 and the wire stopper body 70 are not moved backward by the tension application spring 92 in the first operating range in which the wire W is stopped by the wire stopper body 70. Accordingly, in the first operating range in which the wire W is stopped by the wire stopper body 70, an additional load due to the load caused by the tension application spring 92 that shifts the sleeve 71 and the wire stopper body 70 in the reverse direction is not applied by the operation of moving the sleeve 71 and the wire stopper body 70 in the direction shown by the arrow A1, which is the forward direction.Accordingly, an increase in the additional load applied to the electric motor 80 in the region in which the load caused by the spring 92 for applying tension is unnecessary.

[0087] The rotary shaft 72 is connected to the reducer 81 via the connecting block 72b, which rotates integrally with the reducer 81 and is movable in the axial direction relative to the reducer 81. In the first working range in which the wire W is stopped by the wire stopping body 70 from the ready position, since the sleeve 71 and the wire stopping body 70 are not moved backward by the tension applying spring 92, the position of the rotary shaft 72 in the axial direction cannot be adjusted by the tension applying spring 92 in the first working range. Therefore, the connecting block 72b includes a spring 72c, which moves the rotary shaft 72 backward, which is a direction approaching the reducer 81.Accordingly, the position of the rotary shaft 72 is adjusted by receiving a force for pushing backward by means of the spring 72c if there is no force for moving in the forward direction beyond the bias force applied by means of the spring 72c.

[0088] Accordingly, by providing the tension application spring 92 independently of the spring 72c, the load necessary for preventing the wire W from loosening can be applied in the required region, and in the second operating range in which the wire W is cut, since the sleeve 71 and the wire stopper body 70 can be shifted backward by the tension application spring 92, the effect of allowing the wire W wound around the reinforcing bars S to be prevented from loosening before twisting is achieved. In addition to this effect, by preventing an increase in the additional load applied to the motor 80 in the region in which the load caused by the shifting of the tension application spring 92 is unnecessary, an increase in the additional load applied to the motor 80 and the like in the entire one binding cycle can be prevented, and a decrease in the wear resistance of the components can be prevented.In addition, by providing the spring 72c, it is possible to prevent the rotation shaft 72 from moving excessively in the region in which the bias force applied by the spring 92 for applying tension is not applied.

[0089] When the electric motor 80 is driven in the forward rotation direction to move the sleeve 71 in the forward direction indicated by the arrow A1 to cut the wire W, the bending blocks 71c1 and 71c2 move in a direction approaching the reinforcing bars S almost simultaneously. Accordingly, as illustrated in Fig. 5F, the far end side of the wire W, locked by the central hook 70C and the second side hook 70R, is pressed against the side of the reinforcing bar S by the bending block 71c1 and is bent toward the side of the reinforcing bar S with the locking position as a fulcrum. When the sleeve 71 is further moved in the forward direction, the wire W locked between the second side hook 70R and the central hook 70C is held in a compressed state by the bending block 71c1.

[0090] Additionally, the tail end side of the wire W, locked by the central hook 70C and the first side hook 70L and cut in the cutting block 6A, is pressed against the side of the reinforcing bar S by the bending block 71c2 and is bent toward the reinforcing bar S with the locking position as a fulcrum. When the sleeve 71 is further moved in a forward direction, the wire W, locked between the first side hook 70L and the central hook 70C, is held in a compressed state by the bending block 71c2. In the third working range in which the wire W is bent and formed, the rotational adjusting blade 74a is locked to the rotational adjusting latch 74b. The sleeve 71 moves in a forward direction without rotating.

[0091] After the far end side and the tail end side of the wire W are bent toward the side of the reinforcing bar S, the electric motor 80 is further driven in the forward rotation direction, causing the sleeve 71 to further move in the forward direction. When the sleeve 71 moves to a predetermined position and reaches the fourth working range in which the wire W, locked by the wire locking body 70, is twisted, the locking of the rotation control blade 74a to the rotation control latch 74b is released.

[0092] Accordingly, when the electric motor 80 is further driven in the forward rotation direction, the sleeve 71 rotates in combination with the rotation shaft 72, and the wire W locked by the wire locking body 70 is twisted.

[0093] In the fourth operating range, in which the sleeve 71 rotates to twist the wire W, the binding unit 7A receives a force to pull the wire stopper body 70 forward along the axial direction of the rotation shaft 72 by twisting the wire W locked by the wire stopper body 70. When the sleeve 71 moves in a forward direction to a position in which the sleeve 71 is rotating, the tension application spring 92 is further compressed, and the sleeve 71 receives a force to push by the tension application spring 92 in the reverse direction.

[0094] Accordingly, when a force for moving forward along the axial direction is applied to the wire stopper body 70, as illustrated in Fig. 5G, the sleeve 71 of the wire stopper body 70 receives a pushing force by means of the spring 92 for applying a rearward tension. At the same time, the rotary shaft 72 moves forward while receiving the pushing force by means of the spring 72c, and the wire W is twisted while the rotary shaft 72 moves forward.

[0095] Accordingly, a portion of the wire W locked by the wire locking body 70 is pulled, tension is applied in the tangential direction of the reinforcing bars S, and the wire W is tensioned such that it is in direct contact with the reinforcing bars S. In the binding block 7A, in the fourth working range in which the sleeve 71 rotates to twist the wire W, when the wire locking body 70 is further rotated in combination with the rotation shaft 72, the wire W is further twisted at the time when the wire locking body 70 and the rotation shaft 72 move in a forward direction, which is a direction in which the gap between the twisted portion of the wire W and the reinforcing bars S is reduced.

[0096] Accordingly, as illustrated in Fig. 5H, the wire W is twisted at the time when the wire stopper body 70 and the rotation shaft 72 are moved forward in the state of receiving the force for pushing backward by the tension application spring 92 and the spring 72c. Consequently, the gap between the twisted portion of the wire W and the reinforcing bars S is reduced, and the wire W is brought into direct contact with the reinforcing bars S along the reinforcing bars S. Accordingly, the slack before the wire W is twisted can be removed, and the binding can be performed in the state in which the wire W is in direct contact with the reinforcing bars S.

[0097] When it is detected that the additional load applied to the electric motor 80 is maximized by twisting the wire W, the forward rotation of the electric motor 80 is stopped. Then, when the electric motor 80 is driven in the reverse rotation direction, the rotary shaft 72 rotates in the reverse direction, and the sleeve 71 rotates in the reverse direction according to the reverse rotation of the rotary shaft 72. The rotation of the sleeve 71 in combination with the rotation of the rotary shaft 72 is adjusted by the rotation adjusting blade 74a, which is locked by the rotation adjusting latch 74b. Accordingly, the sleeve 71 moves in the direction shown by arrow A2, which is the reverse direction.

[0098] When the sleeve 71 moves in the reverse direction, the bending blocks 71c1 and 71c2 are separated from the wire W, and the holding of the wire W by the bending blocks 71c1 and 71c2 is released. In addition, when the sleeve 71 moves in the reverse direction, the opening and closing pin 71a passes through the opening and closing guide cavity 73. Accordingly, the first side hook 70L moves in a direction away from the central hook 70C through a rotational operation with the shaft 71b as a fulcrum. The second side hook 70R moves in a direction away from the central hook 70C through a rotational operation with the shaft 71b as a fulcrum. Accordingly, the wire W is removed from the wire locking housing 70.

[0099] Example of the operation and effect of the reinforcing bar tying machine according to the first embodiment As described above, through the operation in which the tension application spring 92 is compressed when the sleeve 71 moves in the forward direction, as indicated by the arrow A1, the front end side, which is one end portion of the tension application spring 92, is pressed against the support member 76d supporting the sleeve 71. The support member 76d is installed in the portion 10A of the main body and does not rotate even when the sleeve 71 rotates. Accordingly, even when the sleeve 71 rotates after moving in the forward direction, the force for rotating the far end side of the tension application spring 92 is not applied to the tension application spring 92.

[0100] A configuration is considered in which the preventing member 93 is not provided, and the rear end side of the tension application spring 92, which is the other end portion of the tension application spring 92, is in direct contact with the rotation control blade 74a, or a configuration in which the rear end side of the tension application spring 92 is in contact with a member that rotates according to the sleeve 71 and the rotation control blade 74a. In such a configuration, when the sleeve 71 and the rotation control blade 74a rotate, the rear end side of the tension application spring 92 rotates according to the rotation of the sleeve 71 and the rotation control blade 74a, thereby generating a force for twisting the tension application spring 92.

[0101] On the contrary, in the configuration including the preventing member 93, when the sleeve 71 moves in the forward direction indicated by the arrow A1, the rotation regulating blade 74a, which moves in the forward direction together with the sleeve 71, comes into contact with the preventing member 93. When the sleeve 71 and the rotation regulating blade 74a further move in the forward direction, the preventing member 93 is pressed against the tension application spring 92, and the preventing member 93 is located in the middle between the tension application spring 92 and the rotation regulating blade 74a. The tension application spring 92 is compressed between the support member 76d supporting the sleeve 71 and the rotation regulating blade 74a through the preventing member 93.

[0102] When the sleeve 71 rotates in a state in which the preventing member 93 is arranged in the middle between the tension application spring 92 and the rotation control blade 74a, the preventing member 93 is pressed against the rotation control blade 74a by means of a force for stretching the compressed tension application spring 92, and thereby a force for rotating the preventing member 93 by means of the rotation control blade 74a, which rotates together with the sleeve 71, is applied to the preventing member 93.

[0103] However, since the rotation preventing block 93b is engaged with the shoulder portion 63 to regulate the rotation, the preventing member 93 does not rotate according to the sleeve 71 and the blade 74a to regulate the rotation.

[0104] The rear end of the tension application spring 92 is pressed against the preventing member 93 by the force for extending the compressed tension application spring 92, but since the preventing member 93 does not rotate according to the sleeve 71 and the rotation adjusting blade 74a, the force for rotating the rear end of the tension application spring 92 is not applied to the tension application spring 92, even when the sleeve 71 and the rotation adjusting blade 74a rotate. Accordingly, even when the sleeve 71 rotates after moving in the forward direction, the generation of a force for twisting the tension application spring 92 is prevented, and an additional load is prevented from being applied in a direction different from the direction in which the tension application spring 92 is compressed and extended to the tension application spring 92, which is a coil spring.Accordingly, the wear resistance of the spring 92 for applying tension can be increased.

[0105] Example of the Configuration of the Rebar Binding Machine According to the Second Embodiment Fig. 6 is a partial side sectional view illustrating an example of the configuration of the main parts of the rebar binding machine according to the second embodiment. The overall configuration of the rebar binding machine 1B according to the second embodiment is identical to the overall configuration of the rebar binding machine 1A according to the first embodiment. Components identical to those of the rebar binding machine 1A according to the first embodiment are denoted by the same reference numerals, and detailed descriptions thereof will be omitted.

[0106] The reinforcing bar binding machine 1B according to the second embodiment includes a preventing member 94 that prevents the generation of a force for twisting the spring 92 for applying tension. The preventing member 94 is realized by a bearing and rotatably supports the sleeve 71 relative to the main body section 10A on the front end side, which is one end section of the spring 92 for applying tension. In the preventing member 94, the inner annular section 94a of the bearing supporting the sleeve 71 rotates in combination with the sleeve 71, and the outer annular section 94b of the bearing seated in the main body section 10A does not rotate.

[0107] In the sleeve 71, the spacer 95 is inserted between the preventing member 94 and the tension application spring 92. The spacer 95 has an annular shape, comes into contact with the inner annular portion 94a of the bearing implementing the preventing member 94, and rotates according to the sleeve 71 and the inner annular portion 94a of the preventing member 94. The front end side of the tension application spring 92 comes into contact with the spacer 95 and can rotate according to the sleeve 71 and the inner annular portion 94a of the preventing member 94 through the spacer 95.

[0108] Example of Operation of Rebar Binding Machine According to the Present Embodiment Figs. 7A, 7B, 7C, 7D, 7E, 7F, 7G and 7H are side sectional views of main parts illustrating examples of operations of the rebar binding machine according to the second embodiment. Fig. 7A shows a state in which the rebars S are arranged in a position in which they can be tied. Fig. 7B illustrates an operation of feeding the wire W in a forward direction and winding the wire W around the rebars S. Fig. 7C illustrates an operation of stopping the wire W wound around the rebars S. Fig. 7D illustrates an operation of feeding the wire W in a reverse direction and winding the wire W around the rebars S. Fig. 7E illustrates the operation of cutting off the excess portion of wire W wrapped around reinforcing bars S. Fig. 7F illustrates the operation of bending wire W wrapped around reinforcing bars S. Fig.7G and 7H illustrate the twisting operation of wire W wrapped around reinforcing bars S.

[0109] The following describes the operation of tying reinforcing bars S using wire W by means of a reinforcing bar tying machine 1B according to a second embodiment with reference to the drawings.

[0110] In the reinforcing bar binding machine 1B, similar to the reinforcing bar binding machine 1A according to the first embodiment, in the ready state, as illustrated in Fig. 7A, the reinforcing bars S are inserted between the bending guide 50 and the advancing guide 51 of the bend forming unit 5A. When the trigger 12A is pressed, the feeding motor (not illustrated) is driven in the forward rotation direction, and, as illustrated in Fig. 7B, the wire W is fed in the forward direction indicated by the arrow F by the wire feeding unit 3A.

[0111] When 2 W wires are fed, the 2 W wires are fed by the wire guide 4A in a state of being arranged in parallel along the axial direction of the loop Ru formed by the W wires.

[0112] The wire W, fed in a forward direction, passes between the central hook 70C and the first side hook 70L and is fed into the bending guide 50 of the bend forming unit 5A. The wire W is wrapped around the reinforcing bars S by passing through the bending guide 50.

[0113] The wire W wound by the bending guide 50 is guided by the advancing guide 51 and further fed in a forward direction by the wire feeding unit 3A and then guided between the central hook 70C and the second side hook 70R by the advancing guide 51. After this, the wire W is fed until its distal end is adjacent to the feeding control unit 90. When the wire W is fed to a position in which the distal end of the wire W is adjacent to the feeding control unit 90, the driving of the feeding motor (not illustrated) is stopped.

[0114] After the wire W is fed forward, the electric motor 80 is driven in the forward rotation direction. For the sleeve 71, in the first operating range in which the wire W is stopped by the wire stopping body 70, the rotation of the sleeve 71 in combination with the rotation of the rotation shaft 72 is controlled by locking the rotation regulating blade 74a to the rotation regulating latch 74b. Accordingly, as illustrated in Fig. 7C, the rotation of the electric motor 80 is converted into a linear movement, and the sleeve 71 moves in the direction shown by arrow A1, which is the forward direction.

[0115] When the sleeve 71 moves in a forward direction, the opening and closing pin 71a passes through the opening and closing guide cavity 73. Accordingly, the first side hook 70L moves in a direction approaching the central hook 70C through a rotation operation with the shaft 71b as a fulcrum. When the first side hook 70L closes relative to the central hook 70C, the wire W, placed in the middle between the first side hook 70L and the central hook 70C, is locked in a shape moved between the first side hook 70L and the central hook 70C.

[0116] Additionally, the second side hook 70R moves in a direction approaching the central hook 70C through a rotating operation with the shaft 71b as a fulcrum. When the second side hook 70R closes relative to the central hook 70C, the wire W, located midway between the second side hook 70R and the central hook 70C, is stopped so that it is not torn off by the second side hook 70R and the central hook 70C.In the reinforcing bar binding machine 1B, in the first operating range in which the wire W is stopped by the wire stopping body 70, the sleeve 71 and the wire stopping body 70 are not moved backward by the tension applying spring 92, and an additional load due to the tension applying spring 92 is not applied by an operation in which the sleeve 71 and the wire stopping body 70 are moved in the direction shown by the arrow A1, which is a straight direction.

[0117] After the sleeve 71 moves forward to a position in which the wire W is stopped by the closing operation of the first side hook 70L and the second side hook 70R, the rotation of the motor 80 is temporarily stopped, and the feeding motor (not illustrated) is driven in the reverse rotation direction.

[0118] Accordingly, the pair of feed gears 30 rotate in the reverse direction, and, as illustrated in Fig. 7D, the wire W held between the pair of feed gears 30 is fed in the reverse direction indicated by the arrow R. Since the far end side of the wire W is stopped so that it does not come off between the second side hook 70R and the central hook 70C, the wire W is wound around the reinforcing bars S by the operation of feeding the wire W in the reverse direction.

[0119] After the wire W is wrapped around the reinforcing bars S and the driving of the feeding motor 31 in the reverse rotation direction is stopped, the motor 80 is driven in the forward rotation direction to further move the sleeve 71 in the forward direction indicated by the arrow A1. As illustrated in Fig. 7E, the operation in which the sleeve 71 moves in the forward direction is transmitted to the cutting unit 6A by the transmission mechanism 62, and then the movable blade unit 61 rotates. The wire W, locked by the first side hook 70L and the central hook 70C, is cut by the operations of the fixed blade unit 60 and the movable blade unit 61.In the reinforcing bar binding machine 1B, in the second working range in which the sleeve 71 and the wire stopper body 70 move in the forward direction to cut the wire W, the rotation regulating blade 74a comes into contact with the tension applying spring 92, the tension applying spring 92 is compressed between the preventing member 94 and the rotation regulating blade 74a, and the sleeve 71 and the wire stopper body 70 are moved backward by the tension applying spring 92.

[0120] In the second working range in which the wire W is cut, the sleeve 71 is shifted in the reverse direction by the tension application spring 92 compressed between the preventing member 94 and the rotation regulating blade 74a, through an operation in which the sleeve 71 is moved in the forward direction. Therefore, by preventing the sleeve 71 from moving in the forward direction, the force for pulling the wire W stopped by the wire stopper body 70 is prevented from decreasing. Accordingly, the tension applied to the wire W is maintained by the operation of feeding the wire W in the reverse direction and winding the wire W around the reinforcing bars S, and the wire W wound around the reinforcing bars S is prevented from loosening before twisting.

[0121] When the electric motor 80 is driven in the forward rotation direction to move the sleeve 71 in the forward direction indicated by the arrow A1 to cut the wire W, the bending blocks 71c1 and 71c2 move in a direction approaching the reinforcing bars S almost simultaneously. Accordingly, as illustrated in Fig. 7F, the far end side of the wire W, locked by the central hook 70C and the second side hook 70R, is pressed against the side of the reinforcing bar S by the bending block 71c1 and is bent toward the side of the reinforcing bar S with the locking position as a fulcrum. When the sleeve 71 is further moved in the forward direction, the wire W locked between the second side hook 70R and the central hook 70C is held in a compressed state by the bending block 71c1.

[0122] Additionally, the tail end side of the wire W, locked by the central hook 70C and the first side hook 70L and cut by the cutting block 6A, is pressed against the side of the reinforcing bar S by the bending block 71c2 and is bent toward the reinforcing bar S with the locking position as a fulcrum. When the sleeve 71 is further moved in a forward direction, the wire W, locked between the first side hook 70L and the central hook 70C, is held in a compressed state by the bending block 71c2. In the third working range in which the wire W is bent and formed, the rotational adjusting blade 74a is locked to the rotational adjusting latch 74b. The sleeve 71 moves in a forward direction without rotating.

[0123] After the far end side and the tail end side of the wire W are bent toward the side of the reinforcing bar S, the electric motor 80 is further driven in the forward rotation direction, causing the sleeve 71 to further move in the forward direction. When the sleeve 71 moves to a predetermined position and reaches the fourth working range in which the wire W, locked by the wire locking body 70, is twisted, the locking of the rotation control blade 74a to the rotation control latch 74b is released.

[0124] Accordingly, when the electric motor 80 is further driven in the forward rotation direction, the sleeve 71 rotates in combination with the rotation shaft 72, and the wire W locked by the wire locking body 70 is twisted.

[0125] In the fourth operating range, in which the sleeve 71 rotates to twist the wire W, the binding unit 7A receives a force to pull the wire stopper body 70 forward along the axial direction of the rotation shaft 72 by twisting the wire W locked by the wire stopper body 70. When the sleeve 71 moves in a forward direction to a position in which the sleeve 71 is rotating, the tension application spring 92 is further compressed, and the sleeve 71 receives a force to push by the tension application spring 92 in the reverse direction.

[0126] Accordingly, when a force for moving forward along the axial direction is applied to the wire stopper body 70, as illustrated in Fig. 7G, the sleeve 71 of the wire stopper body 70 receives a pushing force by means of the spring 92 for applying a rearward tension. At the same time, the rotary shaft 72 moves forward while receiving the pushing force by means of the spring 72c, and the wire W is twisted while the rotary shaft 72 moves forward.

[0127] Accordingly, a portion of the wire W locked by the wire locking body 70 is pulled, tension is applied in the tangential direction of the reinforcing bars S, and the wire W is tensioned such that it is in direct contact with the reinforcing bars S. In the binding unit 7A, in the fourth working range in which the sleeve 71 rotates to twist the wire W, when the wire locking body 70 is further rotated in combination with the rotation shaft 72, the wire W is further twisted at the time when the wire locking body 70 and the rotation shaft 72 move in a forward direction, which is a direction in which the gap between the twisted portion of the wire W and the reinforcing bars S is reduced.

[0128] Accordingly, as illustrated in Fig. 7H, the wire W is twisted at the time when the wire stopper body 70 and the rotation shaft 72 are moved forward in the state of receiving the force for pushing backward by the tension application spring 92 and the spring 72c. Consequently, the gap between the twisted portion of the wire W and the reinforcing bars S is reduced, and the wire W is brought into direct contact with the reinforcing bars S along the reinforcing bars S. Accordingly, the slack before the wire W is twisted can be removed, and the binding can be performed in the state in which the wire W is in direct contact with the reinforcing bars S.

[0129] When it is detected that the additional load applied to the electric motor 80 is maximized by twisting the wire W, the forward rotation of the electric motor 80 is stopped. Then, when the electric motor 80 is driven in the reverse rotation direction, the rotary shaft 72 rotates in the reverse direction, and the sleeve 71 rotates in the reverse direction according to the reverse rotation of the rotary shaft 72. The rotation of the sleeve 71 in combination with the rotation of the rotary shaft 72 is adjusted by the rotation adjusting blade 74a, which is locked by the rotation adjusting latch 74b. Accordingly, the sleeve 71 moves in the direction shown by arrow A2, which is the reverse direction.

[0130] When the sleeve 71 moves in the reverse direction, the bending blocks 71c1 and 71c2 are separated from the wire W, and the holding of the wire W by the bending blocks 71c1 and 71c2 is stopped. In addition, when the sleeve 71 moves in the reverse direction, the opening and closing pin 71a passes through the opening and closing guide cavity 73. Accordingly, the first side hook 70L moves in a direction away from the central hook 70C through a rotational operation with the shaft 71b as a fulcrum. The second side hook 70R moves in a direction away from the central hook 70C through a rotational operation with the shaft 71b as a fulcrum. Accordingly, the wire W is removed from the wire locking housing 70.

[0131] Example of operation and effect of reinforcing bar tying machine according to second embodimentAs described above, by the operation in which the tension application spring 92 is compressed when the sleeve 71 moves in the forward direction as indicated by the arrow A1, the front end side, which is one end portion of the tension application spring 92, is pressed, through the spacer 95, against the inner annular portion 94a of the preventing member 94 supporting the sleeve 71.

[0132] The inner annular portion 94a of the preventing member 94 supporting the sleeve 71 rotates in combination with the sleeve 71, and the gasket 95 comes into contact with the inner annular portion 94a of the preventing member 94 and rotates according to the sleeve 71. The front end side of the spring 92 for applying tension comes into contact with the gasket 95 and can rotate according to the sleeve 71 and the inner annular portion 94a of the preventing member 94 through the gasket 95.

[0133] The rear end side, which is the other end portion of the tension application spring 92, comes into contact with the rotation control blade 74a. When the tension application spring 92 is compressed, when the sleeve 71 moves in the forward direction, the rear end side of the tension application spring 92 is pressed against the rotation control blade 74a by the force for stretching the compressed tension application spring 92.

[0134] When the sleeve 71 rotates after moving in the forward direction, the rear end of the tension application spring 92 receives a rotational force in accordance with the rotation of the sleeve 71 and the rotation control blade 74a. As described above, the front end of the tension application spring 92 can rotate in accordance with the sleeve 71 and the inner annular portion 94a of the preventing member 94 through the spacer 95.

[0135] Accordingly, when the sleeve 71 rotates after moving in the forward direction, the generation of a force for twisting the tension spring 92 is prevented by rotating the tension spring 92 according to the sleeve 71, and an additional load is prevented from being applied in a direction different from the direction in which the tension spring 92 is compressed and extended to the tension spring 92, which is a coil spring. Accordingly, the wear resistance of the tension spring 92 can be improved.

[0136] Furthermore, as another embodiment of the strapping machine of the present invention, a reinforcing bar strapping machine can be provided that includes both the above-described preventing member 93 in the first embodiment and the above-described preventing member 94 in the second embodiment. According to the reinforcing bar strapping machine, the above-described effects of the first and second embodiments can be achieved.

Claims

1. A strapping machine (1A) comprising: - a rotary shaft (72) driven into rotation by an electric motor (80); - a movable housing (71), which is supported with the possibility of rotation by means of a section (10A) of the main housing through a support element (76d) and rotates around a rotational shaft (72), wherein the movable housing (71) is configured to move in the axial direction of the rotational shaft (72) together with the rotation of the rotational shaft (72); - an elastic body (92) which is compressed by moving the movable body (71) along the axial direction of the rotational shaft (72) and which is configured to apply tension to a wire configured to tie an object to be tied by means of a stretching force, wherein the elastic body (92) includes a coil spring which is compressed and stretched in the axial direction of the movable body (71) along the axial direction of the rotational shaft (72); and - a preventing element (93) designed to prevent the formation of a force for twisting the elastic body (92) by rotating the movable body (71), wherein one end section of the elastic body (92) faces the support element (76d), and the other end section of the elastic body (92) faces the preventing element (93), one end section of the elastic body (92) is pressed against the section of the support element (76d), wherein the section is non-rotating relative to the section (10A) of the main body, the other end section of the elastic body (92) is pressed against the preventing element (93), wherein rotation of at least a section of the preventing element (93), which is pressed by means of the elastic body (92), is prevented in accordance with the rotation of the movable body (71).

2. A strapping machine (1B), comprising: - a rotary shaft (72) driven into rotation by an electric motor (80); - a movable housing (71) which moves in the axial direction of the rotary shaft (72) together with the rotation of the rotary shaft (72) and which rotates around the rotary shaft (72); - an elastic body (92) which is compressed by moving the movable body (71) along the axial direction of the rotational shaft (72) and which is configured to apply tension to a wire configured to tie an object to be tied by means of a stretching force, wherein the elastic body (92) includes a coil spring which is compressed and stretched in the axial direction of the movable body (71) along the axial direction of the rotational shaft (72); and - a preventing element (94) designed to prevent the formation of a force for twisting the elastic body (92) by rotating the movable body (71), wherein the preventing element (94) causes the elastic body (92) to rotate in accordance with the rotation of the movable body (71), the preventing element (94) supports the movable housing (71) with the possibility of rotation in the section (10A) of the main housing, one end section of the elastic body (92) faces the preventing element (94), the preventing element (94) rotates in accordance with the rotation of the movable housing (71), the preventing element (94) includes a bearing including an inner annular section (94a) that rotates together with the movable housing (71) and an outer annular section (94b) that is mounted on the section (10A) of the main housing, wherein one end section of the elastic housing (92) is pressed against the inner annular section (94a).

3. The strapping machine according to item 1, in which: - a preventing element (93) is made between the elastic body (92) and the element (74a), which is made on the movable body (71) and which has the ability to regulate the rotation of the movable body (71).

4. The strapping machine according to item 1, in which: - the preventing element (93) has a plate shape.

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