JP2018109295A - Binding machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To wind a wire securely on a bound object, while suppressing idling of a feed gear that takes place when the wire is pulled back.SOLUTION: A pull-back operation is started for a wire W, when feed operation for the wire W is finished. (S150) A control section 100 compares time T3, when a driving curent Iequals or is greater than a standard driving current I, with preset standard time T3 (S190), when the following is determined to be applicable: time T2is less than standard time T2 (S160); a pull-back amount R2is less than a standard pull-back amount R2 (S170); and the driving current Iequals or is greater than the standard driving current I (S180). The control section 100 finishes the pull-back operation for the wire W by halting a feed motor 32 (S200), in a case the time T3that is when the driving current Iequals or is greater than the standard driving current I equals or is greater than the standard time T3, determining that a first feed gear 30 L and a second feed gear 30R start idling.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a binding machine.

  2. Description of the Related Art Conventionally, a reinforcing bar binding machine that binds reinforcing bars by twisting a wire wound around a reinforcing bar after bending the wire in a loop shape has been widely used. In this type of rebar binding machine, for the purpose of reducing wire consumption, after winding the wire around the rebar, the wire feed motor that feeds the wire reversely rotates to pull back the wire, and then to twist the wire It is popular. The wire feeding operation and the drawing back operation are performed by two feeding gears in which V grooves are formed.

  For example, in Patent Document 1, for the purpose of automatically pulling back a wire in accordance with the diameter of the reinforcing bar, when the wire is pulled back, the drive current of the feed motor is measured every unit time, and the peak current due to the start of reverse rotation of the feed motor is There is described a reinforcing bar binding machine that performs control to stop the feed motor when the measured value after flowing increases by a predetermined amount from the lowest value in the measured value.

  Further, in Patent Document 2, the drive system of the feed mechanism is fixed at the time of pulling back the wire for the purpose of performing stable pulling back of the binding wire regardless of the type of binding wire, external conditions, battery voltage, and the like. There is described a reinforcing bar binding machine including a control means for rotating several times reversely and a slip permitting means of a drive system for limiting the pull back tension applied to the wire to a cutting limit value or less.

Japanese Patent No. 3680804 JP 2004-142913 A

  However, the conventional reinforcing bar binding machine has the following problems. That is, the length with which the wire is pulled back depends on the diameter of the reinforcing bars to be bound. In the conventional reinforcing bar binding machine, control such as pulling back the wire by the same length as the feed amount is performed. For this reason, in a bundle with a long circumference, such as a large-diameter rebar or three small-diameter rebars, the pullback amount is reduced, so that the feed gear is idled. When the feed gear is idle, the wire in contact with the feed gear is scraped, and there is a problem that the shaving residue enters the reinforcing bar binding machine and causes malfunction. Further, since the idling time of the feed gear is an extra drive, there is a problem that the power consumption of the battery is also affected.

  Further, in the reinforcing bar binding machine described in Patent Document 1 and the like, since the feed motor is controlled to be stopped when the wire is wound around the reinforcing bar in the wire pullback operation, the idling of the feed gear with respect to the wire is caused. There is a problem that it cannot be reliably suppressed.

  Accordingly, the present invention has been made in view of the above problems, and provides a binding machine capable of reliably winding a wire around a binding object while suppressing idling of a feed gear that occurs when the wire is pulled back. With the goal.

A binding machine according to the present invention includes a pair of feeding units that pinch a wire, and feed or pull back the pinched wire by rotation driving, and a driving unit that rotationally drives one feeding unit of the pair of feeding units, A drive information detection unit that detects drive information of the drive unit when the wire is pulled back; and a timing of occurrence of idling of the feed unit based on the drive information detected by the drive information detection unit; A control unit that stops the driving unit based on the occurrence timing of the idle rotation,
Is provided.

  In the binding machine according to the present invention, the drive unit includes a motor, and the drive information is information on at least one of a drive current, a drive time, and a rotation speed of the motor.

  In the binding machine according to the present invention, the control unit stops the driving unit at a timing immediately before the idling of the feeding unit occurs.

  In the binding machine according to the present invention, the control unit stops the driving unit at a timing immediately after the idling of the feeding unit occurs.

  According to the present invention, since the idling occurrence timing of the feeding unit is determined and the drive unit is stopped based on the determined idling occurrence timing, idling in the feeding unit can be suppressed. Thereby, generation | occurrence | production of the scrap and scrap of the wire which comes out at the time of idling of a feed part can be suppressed.

It is sectional drawing which shows the structural example of the reinforcing bar binding machine which concerns on one embodiment of this invention. AD is a figure for demonstrating the operation example of the reinforcing bar binding machine in the case of winding a reinforcing bar with a wire and twisting it. It is a block diagram which shows the function structural example of a reinforcing bar binding machine. It is a flowchart which shows the operation example of the reinforcing bar binding machine at the time of pulling back of a wire.

  Exemplary embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

[Section configuration example of reinforcing bar binding machine 1A]
FIG. 1 shows an example of a cross-sectional configuration of a reinforcing bar binding machine 1A according to an embodiment of the present invention. In the reinforcing bar binding machine 1A of FIG. 1, the left side of the paper is the front side of the reinforcing bar binding machine 1A, the right side of the paper is the rear side of the reinforcing bar binding machine 1A, the upper side of the paper is the upper side of the reinforcing bar binding machine 1A, and the lower side of the paper is the reinforcing bar. The lower side of the binding machine 1A.

  As shown in FIG. 1, the reinforcing bar binding machine 1 </ b> A includes a binding machine body 10, a handle part 11 </ b> A, a magazine 2 </ b> A that is a storage part in which a wire W is stored, and a wire feed that sends a wire W stored in the magazine 2 </ b> A. 3A, a wire W sent to the wire feed part 3A, and a guide part 4A for guiding the wire W sent from the wire feed part 3A. Further, the reinforcing bar binding machine 1A includes a curl guide part 5A for winding the wire W sent from the wire feeding part 3A around the reinforcing bar S, a cutting part 6A for cutting the wire W wound around the reinforcing bar S, and the reinforcing bar S. A twisting mechanism 7A for gripping and twisting the wire W wound around the wire W is provided.

  The binding machine body 10 is an elongated tube extending in the front-rear direction (the front-rear direction when the side where the curl guide portion 5A is provided (the one end side) is the front direction and the opposite side (the other end side) is the rear direction). It is comprised by the case which makes a shape, and has the half structure which can be divided | segmented into the left and right of the reinforcing bar binding machine 1A. Inside the binding machine body 10, a twist mechanism 7A, a drive mechanism 8A for driving the twist mechanism 7A, and the like are assembled at predetermined positions.

  The handle portion 11 </ b> A is a part for an operator to grip, and extends substantially downward (vertical direction) from the lower surface on the rear side slightly from the center portion of the binding machine body 10. A trigger 12A for an operator to operate the reinforcing bar binding machine 1A is provided on the front side of the handle part 11A and in the vicinity of the boundary with the binding machine body 10.

  A switch 13A is provided behind the trigger 12A and inside the handle portion 11A. The switch 13A is turned on in response to the pressing operation of the trigger 12A by the operator, and operates the feed motor 32 (see FIG. 3), the torsion motor 80, and the like. A battery 15A is detachably attached to the lower portion of the handle portion 11A.

  The magazine 2A detachably stores a reel 20 on which a long wire W is wound so that it can be fed out. In the reinforcing bar binding machine 1A, the wire W is fed out from the reel 20 while the reel 20 stored in the magazine 2A is rotated by the operation of feeding the wire W by the wire feeding unit 3A and the operation of manually feeding the wire W.

  As a pair of feed members for feeding the wire W, the wire feed section 3A sandwiches the wire W between the first feed gear 30L in the form of a spur gear that feeds the wire W by a rotating operation and the first feed gear 30L. Similarly, a spur gear-like second feed gear 30R is provided. The pair of first feed gear 30L and second feed gear 30R have a spur gear shape in which teeth are formed on the outer peripheral surface of a disk-shaped member. In FIG. 1, the first feed gear 30L is located on the back side of the first feed gear 30R.

  The wire feed portion 3A is configured such that the first feed gear 30L and the second feed gear 30R are provided across the feed path of the wire W, so that the outer peripheral surfaces of the first feed gear 30L and the second feed gear 30R It is configured to face each other. The first feed gear 30L and the second feed gear 30R sandwich the wire W between the opposed portions of the outer peripheral surface. The first feed gear 30L and the second feed gear 30R send the wire W along the extending direction of the wire W.

  The wire feed section 3A switches the rotation direction of the first feed gear 30L and the second feed gear 30R by switching the rotation direction of the feed motor 32, and switches the rotation direction of the wire W. It is done.

  In the reinforcing bar binding machine 1A, the wire W is moved in the forward direction indicated by the arrow X1, that is, in the direction of the curl guide portion 5A by causing the wire feed portion 3A to rotate the first feed gear 30L and the second feed gear 30R forward. The curled guide 5A is wound around the reinforcing bar S. Further, after the wire W is wound around the reinforcing bar S, the first feed gear 30L and the second feed gear 30R are reversed so that the wire W is fed in the reverse direction indicated by the arrow X2, that is, in the direction of the magazine 2A. To be pulled back. The wire W is brought into close contact with the reinforcing bar S by being pulled back after the wire W is wound around the reinforcing bar S.

  The wire feed portion 3A is disposed between the first feed gear 30L and the second feed gear 30R and the handle portion 11A in a direction toward and away from the first feed gear 30L and the second feed gear 30R. A second displacement member 36 to be displaced is provided. An operation button (not shown) for displacing the second displacement member 36 is attached to the second displacement member 36.

  The guide portion 4A is provided between the magazine 2A and the first feed gear 30L and the second feed gear 30R, and regulates the direction of the one or more wires W that have been sent (a plurality of wires). When W is sent, the wires W are arranged in parallel) and the wire W is sent out. The guide portion 4A can also be provided downstream of the first feed gear 30L and the second feed gear 30R in the direction of the arrow X1.

  The curl guide portion 5A includes a first guide portion 50 for winding the wire W fed by the first feed gear 30L and the second feed gear 30R, and the wire W fed from the first guide portion 50. A second guide 51 is provided for guiding to the twisting mechanism 7A.

  The first guide portion 50 includes a guide groove 52 that constitutes a feed path of the wire W, and guide pins 53 and 53 b as guide members that wind the wire W in cooperation with the guide groove 52.

  The guide groove 52 regulates the radial direction of the wire W perpendicular to the feeding direction of the wire W together with the guide portion 4A.

  The guide pin 53 is provided on the introduction portion side of the wire W fed by the first feed gear 30L and the second feed gear 30R in the first guide portion 50, and with respect to the feed path of the wire W by the guide groove 52. , The inner side of the loop Ru formed by the wire W in the radial direction. The guide pin 53 regulates the feed path of the wire W so that the wire W fed along the guide groove 52 does not enter the inner side in the radial direction of the loop Ru formed by the wire W.

  The guide pin 53b is provided on the discharge portion side of the wire W fed by the first feed gear 30L and the second feed gear 30R in the first guide portion 50, and with respect to the feed path of the wire W by the guide groove 52. The loop Ru formed by the wire W is disposed outside in the radial direction.

  The wire W fed by the first feed gear 30L and the second feed gear 30R has at least two points on the radially outer side of the loop Ru formed by the wire W and at least one point inside the two points. By restricting the radial position of the loop Ru formed by the wire W at three points, the wire W is curled.

  In this example, with respect to the feeding direction of the wire W fed in the forward direction, the wire is provided at two points: a guide portion 4A provided on the upstream side of the guide pin 53 and a guide pin 53b provided on the downstream side of the guide pin 53. The position of the outer side in the radial direction of the loop Ru formed by W is restricted. Further, the position of the inner side in the radial direction of the loop Ru formed by the wire W is regulated by the guide pin 53.

  The curl guide portion 5A includes a retracting mechanism 53a that retracts the guide pin 53 from a path along which the wire W moves by an operation of winding the wire W around the reinforcing bar S. The retracting mechanism 53a is displaced in conjunction with the operation of the twisting mechanism 7A after the wire W is wound around the reinforcing bar S, and the wire W moves on the guide pin 53 before the timing when the wire W is wound around the reinforcing bar S. Evacuate from the route.

  The second guide portion 51 includes a fixed guide portion 54 that regulates the radial position of the loop Ru formed by the wire W wound around the reinforcing bar S (the movement of the wire W in the radial direction of the loop Ru), The movable guide part 55 which regulates the position (movement of the wire W to the axial direction Ru1 of the loop Ru) of the loop Ru formed by the wire W wound around the reinforcing bar S is provided.

  The movable guide portion 55 has a guide position where the wire fed from the first guide portion 50 can be guided to the second guide portion 51 by a rotation (turning) operation with the shaft as a fulcrum, and the reinforcing bar S to the reinforcing bar binding. It opens and closes with the retreat position where it retreats by the operation of pulling out the machine 1A.

  The cutting portion 6A includes a fixed blade portion (not shown), a rotary blade portion 61 that cuts the wire W in cooperation with the fixed blade portion, and a transmission mechanism 62 that transmits the operation of the torsion mechanism 7A to the rotary blade portion 61. The rotary blade portion 61 cuts the wire W passing through the guide portion 4A of the fixed blade portion by a rotating operation with the shaft as a fulcrum. The transmission mechanism 62 is displaced in conjunction with the operation of the torsion mechanism 7A, winds the wire W around the reinforcing bar S, and then rotates the rotary blade 61 in accordance with the timing of twisting the wire W to cut the wire W.

  The twisting mechanism 7A includes a gripping portion 70 that grips the wire W, a bending portion 71 that bends one end WS side and the other end WE side of the wire W toward the reinforcing bar S, and one of the wires W. A length restricting portion 74 for restricting the position of the end portion WS, a torsion motor 80, and a rotating shaft 82 (see FIG. 2) driven by the torsion motor 80 via a speed reducer 81 that performs deceleration and torque amplification. A movable member 83 that is displaced by the rotation operation of the rotation shaft 82 and a rotation restriction member 84 that restricts the rotation of the movable member 83 in conjunction with the rotation operation of the rotation shaft 82 are provided.

  The gripping part 70 includes a fixed gripping member 70C, a first movable gripping member 70L, and a second movable gripping member 70R (see FIG. 3). The first movable gripping member 70L and the second movable gripping member 70R are arranged in the left-right direction via the fixed gripping member 70C. Specifically, the first movable gripping member 70L is disposed on one side along the axial direction of the wire W to be wound with respect to the fixed gripping member 70C, and the second movable gripping member 70R is on the other side. It is arranged on the side.

  The bending portion 71 bends the wire W so that the end portion of the wire W after binding the reinforcing bars S is positioned closer to the binding object than the top of the wire W that protrudes most in the direction away from the reinforcing bars S. The bending portion 71 bends the wire W gripped by the grip portion 70 before twisting the wire W by the grip portion 70.

  The length restricting portion 74 is configured by providing a member with which one end portion WS of the wire W is abutted on the feeding path of the wire W that has passed between the fixed gripping member 70C and the first movable gripping member 70L. . In this example, the length restricting portion 74 is provided in the first guide portion 50 of the curl guide portion 5A in order to secure a predetermined distance from the holding position of the wire W by the fixed holding member 70C and the first movable holding member 70L. It is done.

  The rotating shaft 82 and the movable member 83 are rotated in the front-rear direction along the rotating shaft 82 of the movable member 83 by the screw portion provided on the rotating shaft 82 and the nut portion provided on the movable member 83. Converted to move. The torsion mechanism 7A is provided integrally with the movable member 83, and moves in the front-rear direction when the movable member 83 moves in the front-rear direction.

  The movable member 83 and the bending portion 71 are rotated by the rotation restricting member 84 by being locked to the rotation restricting member 84 in an operation range where the wire W is grasped by the grasping portion 70 and the wire W is bent by the bending portion 71. Move back and forth in a restricted state. Further, the movable member 83 and the bent portion 71 are rotated by the rotation operation of the rotary shaft 82 by being removed from the locking of the rotation restricting member 84.

  The reinforcing bar binding machine 1 </ b> A includes a control unit 100. The control unit 100 supplies power to the torsion motor 80, the feed motor 32, and the like, and controls each operation of the torsion motor 80 and the like. The control unit 100 is assembled on the upper side of the torsion mechanism 7A, and each wiring is drawn out to the torsion mechanism 7A side.

  An operation unit 16 </ b> A is provided at the rear portion (back surface portion) of the binding machine body 10. The operation unit 16A includes a torque adjustment dial for adjusting the tightening torque of the wire W, a switch for switching the power source of the reinforcing bar binding machine 1A on and off, and an LED that lights up based on the on and off of the switch, etc. Have 16 A of operation parts are connected to the control part 100 via the wiring which is not shown in figure.

[Operation example of reinforcing bar binding machine 1A]
Next, an example of the operation of the reinforcing bar binding machine 1 </ b> A when binding the reinforcing bars S with the wires W will be described with reference to FIGS. 1 and 2. 2A to 2D are diagrams for explaining an example of an operation of gripping and twisting the wire W. FIG.

  As shown in FIGS. 1 and 2A, when the two wires W are fed in the forward direction from the magazine 2A by the first feed gear 30L and the second feed gear 30R, the wires W are connected to the fixed gripping member 70C and the second gripping member 70C. Passes through the guide groove 52 of the first guide portion 50 of the curl guide portion 5A. Thereby, the wire W is attached with a winding rod wound around the reinforcing bar S.

  The wire W fed out from the first guide portion 50 is guided to the fixed guide portion 54 in a state where the movement is restricted by the movable guide portion 55 of the second guide portion 51. The movement of the wire W guided to the fixed guide portion 54 along the radial direction of the loop Ru is restricted by the fixed guide portion 54, and is guided between the fixed gripping member 70C and the first movable gripping member 70L. Then, the tip of the wire W is abutted against the length restricting portion 74. Thereby, the wire W is wound around the reinforcing bar S in a loop shape.

  As shown in FIGS. 1 and 2B, after the feed of the wire W is stopped, the torsion motor 80 is driven in the forward rotation direction, thereby moving the movable member 83 in the arrow direction which is the forward direction. That is, in the movable member 83, the rotation operation linked to the rotation of the torsion motor 80 is regulated by the rotation regulating member 84, and the rotation of the torsion motor 80 is converted into a linear movement. As a result, the movable member 83 moves in the forward direction. A direction in which the first movable gripping member 70L approaches the fixed gripping member 70C by a rotational motion about the shaft 77 as the bending portion 71 moves forward in conjunction with the motion of the movable member 83 moving forward. Move to. Thereby, one end WS side of the wire W is gripped.

  The second movable gripping member 70 </ b> R moves in a direction approaching the fixed gripping member 70 </ b> C by a rotating operation with the shaft 77 as a fulcrum. The wire W is supported in the extending direction by the second movable gripping member 70R moving in a direction approaching the fixed gripping member 70C.

  Furthermore, the movement of the movable member 83 moving forward is transmitted to the retracting mechanism 53a, and the guide pin 53 is retracted from the path along which the wire W moves. After gripping one end WS side of the wire W between the first movable gripping member 70L and the fixed gripping member 70C, the feed motor 32 is driven in the reverse rotation direction, whereby the first feed gear 30L. Is reversed, and the second feed gear 30R is reversed following the first feed gear 30L. As a result, the two wires W are pulled back in the direction of the magazine 2A and sent in the opposite direction. The wire W is wound so as to be in close contact with the reinforcing bar S by the operation of feeding the wire W in the reverse direction.

  After the wire W is wound around the reinforcing bar S and the feeding of the wire W is stopped, the torsion motor 80 is driven in the forward rotation direction, thereby moving the movable member 83 in the forward direction. The movement of the movable member 83 in the forward direction is transmitted to the cutting portion 6A by the transmission mechanism 62, and the other end WE side of the wire W gripped by the second movable gripping member 70R and the fixed gripping member 70C is the rotary blade portion. It is cut by the operation of 61.

  As shown in FIG. 2B, after the wire W is cut, the movable member 83 is further moved in the forward direction, whereby the bent portion 71 is moved in the forward direction integrally with the movable member 83.

  As shown in FIG. 2C, the bending portion 71 moves by a predetermined distance in the forward direction indicated by the arrow F, so that one end portion WS of the wire W gripped by the fixed gripping member 70C and the first movable gripping member 70L. The side is pressed to the rebar S side by the bending portion 71b1 and bent to the rebar S side with the gripping position as a fulcrum. Further, when the bending portion 71 is further moved forward, the opening / closing pin 71a is moved in the opening / closing guide hole 77R, so that the wire W of the wire W is interposed between the second movable gripping member 70R and the fixed gripping member 70C. There is a gap through which one end WE is sent.

  Further, the bending portion 71 moves a predetermined distance in the forward direction indicated by the arrow F, so that the other end WE side of the wire W held by the fixed holding member 70C and the second movable holding member 70R is bent. 71b2 is pressed to the reinforcing bar S side and bent to the reinforcing bar S side with the gripping position as a fulcrum.

  As shown in FIGS. 1 and 2D, after the end portion of the wire W is bent to the reinforcing bar S side, the torsion motor 80 is further driven in the forward rotation direction, so that the torsion motor 80 further moves the movable member 83 forward. The direction is moved in the direction of arrow F. When the movable member 83 moves to a predetermined position in the direction of the arrow F, the movable member 83 comes off from the locking of the rotation restricting member 84, and the restriction of rotation by the rotation restricting member 84 of the movable member 83 is released. As a result, the torsion motor 80 is further driven in the forward rotation direction, whereby the gripping portion 70 that grips the wire W rotates and twists the wire W. The gripping portion 70 is urged rearward by a spring (not shown), and twists while applying tension to the wire W. Therefore, the reinforcing bar S is bound by the wire W without the wire W being loosened.

[Block configuration example of reinforcing bar binding machine 1A]
FIG. 3 is a block diagram illustrating an example of a functional configuration of the reinforcing bar binding machine 1A. As shown in FIG. 3, the reinforcing bar binding machine 1 </ b> A includes a control unit 100 that controls the operation of the entire machine. The control unit 100 includes a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and the like, and reads and executes a program stored in a memory such as a ROM to reinforce the reinforcing bar. A bundling process for bundling S with the wire W is performed.

  A forward / reverse drive circuit 120, a rotation speed detection circuit 130, and a current detection circuit (drive information detection unit) 140 are connected to the control unit 100, respectively. A feed motor (drive unit) 32 is connected to the forward / reverse drive circuit 120.

  The forward / reverse drive circuit 120 includes, for example, a driver circuit, generates a drive signal for rotating the feed motor 32 forward or backward based on a control signal supplied from the control unit 100, and supplies the drive signal to the feed motor 32. .

  The feed motor 32 is constituted by, for example, a DC motor or the like, and is connected to the first feed gear 30L via a gear (not shown). The feed motor 32 is driven based on the drive signal supplied from the forward / reverse drive circuit 120, and rotates the first feed gear 30L and the second feed gear 30R driven by the first feed gear 30L in the forward and reverse directions.

  The rotation speed detection circuit 130 is composed of an encoder, for example, and is attached to the feed motor 32. The rotation speed detection circuit 130 detects the rotation speed of the feed motor 32 and supplies the detection result (rotation pulse) to the control unit 100.

  The current detection circuit 140 is connected between the forward / reverse drive circuit 120 and the feed motor 32, detects drive current as drive information supplied from the forward / reverse drive circuit 120 to the feed motor 32, and detects the detected drive current. Supply to the control unit 100.

  The controller 100 receives the rotation speed (number of pulses) of the feed motor 32 from the rotation speed detection circuit 130, and receives the drive current of the feed motor 32 from the current detection circuit 140. The control unit 100 controls the operation of the feed motor 32 based on the input rotation speed and drive current of the feed motor 32 and the time counted by the timer 110, and feeds and retracts the wire W. The idling prevention operation of the feed gear 30L and the like is performed. Further, the control unit 100 determines the occurrence timing of idling of the first feed gear 30L and the like based on the drive current of the feed motor 32 detected by the current detection circuit 140 in the idling prevention operation, Based on this, control for stopping the driving of the feed motor 32 is executed.

[About the drive current of the feed motor 32]
Next, changes in the drive current of the feed motor 32 when the reinforcing bars S are bound by the wires W will be described. When feeding of the wire W in the forward direction is completed and the feed motor 32 is switched from forward rotation to reverse rotation, the rotational load of the feed motor 32 increases and the drive current I _REF becomes the first peak value. Thereafter, as the rotational speed of the feed motor 32 increases, the drive current I _REF gradually decreases. As the wire W is pulled back and wound around the reinforcing bar S (when in close contact), the rotational load of the feed motor 32 increases, and the drive current I _REF changes from decreasing to increasing.

When the wire W is completely wound around the reinforcing bar S and the wire W is reliably pulled back, the rotational load of the feed motor 32 further increases, and the drive current I _REF becomes the second peak value. In this state, when the reverse rotation of the feed motor 32 continues, the first feed gear 30L and the second feed gear 30R idle with respect to the wire W.

[Operation example of rebar binding machine 1A when wire W is pulled back]
FIG. 4 shows an example of the operation of the control unit 100 of the reinforcing bar binding machine 1A when the wire W is pulled back. The control unit 100 implements the processing shown in FIG. 4 below by reading and executing a program stored in a memory such as a ROM.

  As shown in FIG. 4, in step S100, when the switch 13A is turned on by the operator pressing the trigger 12A, the control unit 100 starts the wire W feeding operation and proceeds to step S110.

  In step S <b> 110, the control unit 100 rotates the feed motor 32 forward via the forward / reverse drive circuit 120. Thereby, the wire W is sent in the forward direction (arrow X1). Further, the control unit 100 measures the feed amount of the wire W based on the rotation speed of the feed motor 32 detected by the rotation speed detection circuit 130. The timer 110 of the control unit 100 starts counting time. When step S110 ends, the process proceeds to step S120.

In step S120, the control unit 100 compares the time T1 _REF counted by the timer 110 with a preset reference time T1. When the control unit 100 determines that the time T1 _REF is equal to or longer than the reference time T1, it is a timing before the wire W feed amount R1 _REF described later reaches the reference feed amount R1, and therefore the wire W feed for some reason. It is determined that a problem such as a defect has occurred, and the process proceeds to step S210. In step S210, the control unit 100 stops the feed motor 32. On the other hand, when the control unit 100 determines that the time T1 _REF is less than the reference time T1, the control unit 100 proceeds to step S130.

In step S130, the control unit 100 compares the feed amount R1 _{REF of the} wire W calculated from the rotational speed of the feed motor 32 detected by the rotational speed detection circuit 130 with a preset reference feed amount R1. . If the feed amount R1 _REF is less than the reference feed amount R1, the control unit 100 determines that the feed of the wire W has not been completed, returns to step S120, and continues to feed the wire W in the forward direction. . On the other hand, when the feed amount R1 _REF is equal to or greater than the reference feed amount R1, the control unit 100 determines that the feed of the wire W has ended normally and proceeds to step S140.

  In step S <b> 140, the control unit 100 stops the feed motor 32 via the forward / reverse drive circuit 120. Thereby, the feeding of the wire W is also stopped. In addition, the control unit 100 stops measuring the feed amount of the wire W, and the timer 110 also stops counting time. When step S140 ends, the process proceeds to step S150.

In step S <b> 150, the control unit 100 starts a pull back operation of the wire W after the feed motor 32 is stopped. Specifically, the control unit 100 reversely rotates the feed motor 32 via the forward / reverse drive circuit 120. Thereby, the wire W is pulled back in the reverse direction (arrow X2). Further, the control unit 100 measures the pullback amount R2 _REF of the wire W based on the rotation speed of the feed motor 32 detected by the rotation speed detection circuit 130. The timer 110 starts counting time. Further, the control unit 100 monitors the drive current I _REF of the feed motor 32 input from the current detection circuit 140 with the start of the pullback operation of the wire W, and the first feed gear 30L and the second feed gear. It is monitored whether or not idling occurs at 30R. When step S150 ends, the process proceeds to step S160.

In step S160, the control unit 100 compares the time T2 _REF counted by the timer 110 with a preset reference time T2. When it is determined that the time T2 _REF has reached the reference time T2, the control unit 100 is the timing before the return amount R2 _REF of the wire W reaches the reference feed amount R2. It is determined that it has occurred, and the process proceeds to step S210. In step S210, the control unit 100 stops the feed motor 32. On the other hand, in step S160, when the control unit 100 determines that the time T2 _REF is less than the reference time T2, the process proceeds to step S170.

In step S170, the control unit 100 compares the pullback amount R2 _{REF of the} wire W calculated from the rotation number of the feed motor 32 detected by the rotation number detection circuit 130 with a preset reference pullback amount R2. . When the pullback amount R2 _REF reaches the reference pullback amount R2, the control unit 100 proceeds to step S210. For example, when pulling back is performed in a state where the tip of the wire W is not gripped due to a feed failure, the drive current I _REF does not increase and the wire W passes through the wire feed portion 3A. Can be considered. In step S210, the control unit 100 stops the feed motor 32. On the other hand, when determining that the pullback amount R2 _REF is less than the reference pullback amount R2, the control unit 100 proceeds to step S180.

In step S180, the control unit 100 compares the driving current I _REF of the feed motor 32 detected by the current detection circuit 140 with a preset reference driving current I. When the drive current I _REF is less than the reference drive current I, the control unit 100 determines that the wire W is not wound (not in close contact) with the reinforcing bar S, returns to step S160, and continues to pull the wire W back. And do it. On the other hand, when determining that the drive current I _REF is equal to or greater than the reference drive current I, the control unit 100 determines that the wire W is wound around the reinforcing bar S and proceeds to step S190.

In step S190, the control unit 100 compares the time T3 _REF when the drive current I _REF is greater than or equal to the reference drive current I with a preset reference time T3. Here, the reference time T3 is a time during which the wire W is reliably pulled back and the idling of the first feed gear 30L and the second feed gear 30R does not start. When the time T3 _REF when the drive current I _REF is greater than or equal to the reference drive current I is less than the reference time T3, the control unit 100 determines that the timing is before the idle rotation of the wire W and returns to Step S160. Then, the wire W is pulled back continuously.

On the other hand, when the time T3 _REF when the drive current I _REF is greater than or equal to the reference drive current I is greater than or equal to the reference time T3, the control unit 100 starts idling of the first feed gear 30L and the second feed gear 30R. The process proceeds to step S200. In step S <b> 200, the control unit 100 stops the feed motor 32 via the forward / reverse drive circuit 120 and ends the wire W pull-back operation. In the present embodiment, the wire W feeding operation, the pulling back operation, and the idling prevention processing at the time of pulling back are repeatedly executed.

In addition, since the pullback amount R2 _REF <the pullback amount R1 _REF and the time T2 _REF <the time T1 _REF , the tip of the pulled wire W passes through the first feed gear 30L and the second feed gear 30R. The feed motor 32 never stops before.

As a modification of the above-described embodiment, the processes in steps S180 and S190 shown in FIG. 4 can be changed to another control. Specifically, in step S180 of FIG. 4, the control unit 100 determines that the drive current (drive information) I _{REF of} the feed motor 32 detected by the current detection circuit 140 is less than a preset reference drive current I. If it is determined, the process returns to step S160 and the wire W is continuously pulled back. On the other hand, when the control unit 100 determines that the drive current I _REF matches the reference drive current I (is the same value), the control unit 100 proceeds to step S190. Here, the reference drive current I refers to a current value at which the wire W can be pulled back and the first feed gear 30L and the second feed gear 30R do not run idle.

In step S190, the control unit 100 performs control so that the drive current I _REF of the feed motor 32 is maintained at the reference drive current I, and the time T3 _{REF in} that state is less than the preset reference time T3. Returning to step S160, the wire W is pulled back continuously. On the other hand, when the time T3 _REF is equal to or longer than a preset reference time T3, the control unit 100 determines that the timing is just before the first feed gear 30L and the second feed gear 30R start idling. Proceed to step S200. Here, the reference time T3 refers to a time during which the wire W can be reliably pulled back and the first feed gear 30L and the second feed gear 30R do not start idling.

  In step S <b> 200, the control unit 100 stops the feed motor 32 via the forward / reverse drive circuit 120 and ends the wire W pull-back operation. Thereby, the feed motor 32 can be stopped immediately before the idling of the first feed gear 30L and the second feed gear 30R starts.

  As described above, according to the present embodiment, when it is determined that the first feed gear 30L and the second feed gear 30R are idling when the wire W is pulled back, the feed motor 32 is stopped and the first feed gear 32R is stopped. The pullback operation of the gear 30L and the second feed gear 30R is stopped. Thereby, idling in the first feed gear 30L and the second feed gear 30R can be prevented in advance, and generation of scraped scraps of the wire W that occurs during idling can be suppressed.

  Further, according to the present embodiment, since the idling of the first feed gear 30L and the second feed gear 30R can be suppressed, unnecessary driving of the first feed gear 30L and the second feed gear 30R is reduced. be able to. As a result, the power consumption of the battery 15A can be effectively suppressed. Furthermore, according to the present embodiment, since idling in the first feed gear 30L and the second feed gear 30R can be suppressed, heat generation of the feed motor 32 can also be suppressed.

  Although the present invention has been described using the embodiment, the technical scope of the present invention is not limited to the scope described in the embodiment. Various modifications or improvements can be added to the above-described embodiment without departing from the spirit of the present invention. In addition, one or more of the requirements described in the above embodiments may be omitted. Furthermore, the execution order of processes such as operations and steps in the apparatus and program shown in this specification can be realized in any order as long as the output of the previous process is not used in the subsequent process.

  In embodiment mentioned above, although the example which binds the reinforcing bar S using two wires W was demonstrated, it is not limited to this. For example, the present invention can be applied to a reinforcing bar binding machine that binds the reinforcing bars S using one wire W or three or more wires W.

  In the above-described embodiment, whether or not the first feed gear 30L and the second feed gear 30R idle with respect to the wire W is determined based on the drive current and time of the feed motor 32. It is not limited to. For example, it is possible to determine whether or not the first feed gear 30L and the second feed gear 30R are idle with respect to the wire W using the drive time and the rotation speed of the feed motor 32 as drive information. Further, it is determined whether or not the first feed gear 30L and the second feed gear 30R are idle with respect to the wire W by using two or more pieces of information among the drive current, drive time, and rotation speed of the feed motor 32. You can also

  In the above-described embodiment, the feed motor 32 is controlled to stop at the timing immediately before the first feed gear 30L and the second feed gear 30R idle with respect to the wire W. However, the present invention is not limited to this. Never happen. For example, the feed motor 32 may be controlled to stop at the timing immediately after the first feed gear 30L and the second feed gear 30R are idle with respect to the wire W. For example, in step S190 of FIG. 4 and its modification, the feed motor 32 is controlled to stop within a range of, for example, 5 to 50 ms after the elapse of the reference time T3, and more preferably within a range of 10 to 30 ms.

1A Rebar tying machine 3A Wire feed part (feed part)
7A Torsion mechanism (binding part)
10 Binder body 12A Trigger 30L First feed gear (feed section)
30R Second feed gear (feed unit)
32 Feed motor (drive unit)
82 Rotating shaft 100 Control unit 140 Current detection circuit (drive information detection unit)
W wire

Claims (4)

A pair of feeding sections that sandwich the wire, and feed or pull back the sandwiched wire;
A drive unit that rotationally drives one of the pair of feed units;
A drive information detection unit for detecting drive information of the drive unit when the wire is pulled back;
A control unit that determines the occurrence timing of idling of the feeding unit based on the driving information detected by the driving information detection unit, and stops the driving unit based on the determined occurrence timing of idling;
A binding machine characterized by comprising: The drive unit includes a motor,
2. The binding machine according to claim 1, wherein the drive information is information of at least one of a drive current, a drive time, and a rotation speed of the motor. The binding device according to claim 1 or 2, wherein the control unit stops the driving unit at a timing immediately before the idling of the feeding unit occurs. 3. The binding machine according to claim 1, wherein the control unit stops the drive unit at a timing immediately after the idling of the feeding unit occurs.

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