REBAR TYING MACHINE

Abstract

A rebar tying machine may include a reel holding section for holding a reel; a reel stopper switchable between a prohibited state in which the reel is prohibited from being removed and a permitted state in which the reel is permitted to be removed; a rotatable first roller; a rotatable second roller, wherein the second roller is switchable between a first state in which a wire is held between the first roller and the second roller and a second state in which a distance between the first roller and the second roller is longer than a distance between the first roller and the second roller in the first state; and a twisting unit for twisting the wire. The second roller may be switched from the first state to the second state when the reel stopper switches from the prohibited state to the permitted state.

Description

REFERENCE TO RELATED APPLICATIONS

This application claims priority to Japanese Patent Application No. 2024-003565 filed on Jan. 12, 2024. The entire content of the priority application is incorporated herein by reference.

TECHNICAL FIELD

The disclosure herein relates to rebar tying machines.

BACKGROUND ART

International Publication No. 2021/070481 describes a rebar tying machine. The rebar tying machine includes a reel holding section configured to hold a reel including the wire such that the reel is rotatable about a reel rotation axis; a reel stopper configured to be switchable between a prohibited state in which the reel is prohibited from being removed from the reel holding section and a permitted state in which the reel is permitted to be removed from the reel holding section; a first roller configured to be rotatable; a second roller configured to be rotatable, wherein the second roller is configured to be switchable between a first state in which the wire is held between the first roller and the second roller and a second state in which a distance between the first roller and the second roller is longer than a distance between the first roller and the second roller in the first state; an actuation member configured to move between an open position and a closed position; and a twisting unit configured to twist the wire wound around the rebars by the first roller and the second roller.

SUMMARY

In the rebar tying machine above, the reel stopper switches from the prohibited state to the permitted state after the second roller has switched from the first state to the second state.

Further, to keep the reel stopper in the prohibited state in the rebar tying machine above, a user firstly switches the reel stopper from the permitted state to the prohibited state and then moves the actuation member from the open position to the closed position. Thus, keeping the reel stopper in the prohibited state requires a complex manipulation.

The disclosure herein aims to provide a rebar tying machine that facilitates switching states of a second roller and switching states of a reel stopper, and a rebar tying machine that allows for a less complex manipulation to keep a reel stopper in a prohibited state.

A rebar tying machine disclosed herein may be configured to tie rebars with a wire. The rebar tying machine may comprise a reel holding section configured to hold a reel including the wire such that the reel is rotatable about a reel rotation axis; a reel stopper configured to be switchable between a prohibited state in which the reel is prohibited from being removed from the reel holding section and a permitted state in which the reel is permitted to be removed from the reel holding section; a first roller configured to be rotatable; a second roller configured to be rotatable, wherein the second roller is configured to be switchable between a first state in which the wire is held between the first roller and the second roller and a second state in which a distance between the first roller and the second roller is longer than a distance between the first roller and the second roller in the first state; and a twisting unit configured to twist the wire wound around the rebars by the first roller and the second roller. The second roller may be configured to switch from the first state to the second state when the reel stopper switches from the prohibited state to the permitted state.

According to the configuration above, the second roller switches from the first state to the second state in response to the reel stopper switching from the prohibited state to the permitted state. This facilitates switching of the states of the second roller and switching of the states of the reel stopper.

A rebar tying machine disclosed herein may be configured to tie rebars with a wire. The rebar tying machine may comprise a reel holding section configured to hold a reel including the wire such that the reel is rotatable about a reel rotation axis; a reel stopper configured to be switchable between a prohibited state in which the reel is prohibited from being removed from the reel holding section and a permitted state in which the reel is permitted to be removed from the reel holding section; a first roller configured to be rotatable; a second roller configured to be rotatable, wherein the second roller is configured to be switchable between a first state in which the wire is held between the first roller and the second roller and a second state in which a force for holding the wire between the first roller and the second roller is smaller than a force for holding the wire between the first roller and the second roller in the first state; and a twisting unit configured to twist the wire wound around the rebars by the first roller and the second roller. The second roller may switch from the first state to the second state when the reel stopper switches from the prohibited state to the permitted state.

According to the configuration above, the second roller switches from the first state to the second state in response to the reel stopper switching from the prohibited state to the permitted state. This facilitates switching of the states of the second roller and switching of the states of the reel stopper.

A rebar tying machine disclosed herein may be configured to tie rebars with a wire. The rebar tying machine may comprise a reel holding section configured to hold a reel including the wire such that the reel is rotatable about a reel rotation axis; a reel stopper configured to be switchable between a prohibited state in which the reel is prohibited from being removed from the reel holding section and a permitted state in which the reel is permitted to be removed from the reel holding section; and a lock lever configured to keep the reel stopper in the prohibited state when engaged with the reel holding section. The lock lever may be configured to engage with the reel holding section without being manipulated by a user after the reel stopper has switched from the permitted state to the prohibited state.

According to the configuration above, the user does not have to manipulate the lock lever after the reel stopper has switched from the permitted state to the prohibited state. Thus, a manipulation to keep the reel stopper in the prohibited state is less complex.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 shows a perspective view of a rebar tying machine 2 according to a first embodiment.

FIG. 2 shows a left side view of the rebar tying machine 2 according to the first embodiment, with a reel cover 6 and a left housing 10 removed.

FIG. 3 shows a cross-sectional view of the rebar tying machine 2 according to the first embodiment, in the vicinity of a reel holding section 22.

FIG. 4 shows a cross-sectional view of the rebar tying machine 2 according to the first embodiment, in the vicinity of a lock lever 52.

FIG. 5 shows a perspective view of the rebar tying machine 2 according to the first embodiment, with the reel cover 6 opened.

FIG. 6 shows a cross-sectional view of the reel cover 6 and a feeding unit 74 according to the first embodiment, where the reel cover 6 is at a second position.

FIG. 7 shows a cross-sectional view of the rebar tying machine 2 according to the first embodiment, in the vicinity of the lock lever 52.

FIG. 8 shows a front view of the reel cover 6 and the feeding unit 74 according to the first embodiment, where a second roller 98 is in a first state.

FIG. 9 shows a front view of the reel cover 6 and the feeding unit 74 according to the first embodiment, where the second roller 98 is in a second state.

FIG. 10 shows a cross-sectional view of the reel cover 6 and the feeding unit 74 according to the first embodiment, where the reel cover 6 is closer to a first position than a neutral position is.

FIG. 11 shows a cross-sectional view of rebar tying machines 2 according to the first embodiment and a tenth embodiment, in the vicinity of a guide unit 76.

FIG. 12 shows a cross-sectional view of a cutting unit 78 and a twisting unit 80 according to the first embodiment, where a front end of a cutter 128 is positioned rearward of a wire guide hole 138.

FIG. 13 shows a cross-sectional view of the cutting unit 78 and the twisting unit 80 according to the first embodiment, where the front end of the cutter 128 is positioned forward of the wire guide hole 138.

FIG. 14 shows a perspective view of the cutting unit 78 and the twisting unit 80 according to the first embodiment.

FIG. 15 shows a top view of the rebar tying machine 2 according to the first embodiment, with side plates 168 opened.

FIG. 16 shows a cross-sectional view of the side plate 168, a slide unit 170, and a detection sensor 172 according to the first embodiment.

FIG. 17 shows a perspective view of the rebar tying machine 2 according to the first embodiment, in the vicinity of a bending member 192.

FIG. 18 shows a cross-sectional view of the rebar tying machine 2 according to the first embodiment, in the vicinity of the bending member 192.

FIG. 19 shows a flowchart of a process executed by a control unit 82 according to the first embodiment.

FIG. 20 shows a cross-sectional view of the rebar tying machine 2 according to the first embodiment, in the vicinity of a guide unit 76.

FIG. 21 shows a flowchart of a process executed by the control unit 82 according to the first embodiment.

FIG. 22 shows a flowchart of a process executed by the control unit 82 according to the

first embodiment.

FIG. 23 shows a side view of a wire W and rebars R after the wire W was twisted in the first embodiment.

FIG. 24 shows a perspective view of a rebar tying machine 2 according to a second embodiment.

FIG. 25 shows a left side view of the rebar tying machine 2 according to the second embodiment, with a left housing 10 removed.

FIG. 26 shows a cross-sectional view of the rebar tying machine 2 according to the second embodiment, in the vicinity of a guide unit 76.

FIG. 27 shows a front view of a rebar tying machine 2 according to a sixth embodiment. FIG. 28 shows a front view of a rebar tying machine 2 according to a seventh embodiment.

FIG. 29 shows a front view of a reel cover 6 and a feeding unit 74 according to an eighth embodiment, where a second roller 98 is in a first state.

FIG. 30 shows a front view of the reel cover 6 and the feeding unit 74 according to the eighth embodiment, where the second roller 98 is in a second state.

FIG. 31 shows a cross-sectional view of a rebar tying machine 2 according to ninth and tenth embodiments, in the vicinity of a guide unit 76.

FIG. 32 shows a side view of a guide unit 76 and a twisting unit 80 of a rebar tying machine 2 according to thirteenth and fourteenth embodiments.

DESCRIPTION

Representative, non-limiting examples of the present disclosure will now be described in further detail with reference to the attached drawings. This detailed description is merely intended to teach a person of skill in the art further details for practicing preferred aspects of the present teachings and is not intended to limit the scope of the disclosure. Furthermore, each of the additional features and teachings disclosed below may be utilized separately or in conjunction with other features and teachings to provide improved rebar tying machines, as well as methods for using and manufacturing the same.

Moreover, combinations of features and steps disclosed in the following detailed description may not be necessary to practice the disclosure in the broadest sense, and are instead taught merely to particularly describe representative examples of the disclosure. Furthermore, various features of the above-described and below-described representative examples, as well as the various independent and dependent claims, may be combined in ways that are not specifically and explicitly enumerated in order to provide additional useful embodiments of the present teachings.

All features disclosed in the description and/or the claims are intended to be disclosed separately and independently from each other for the purpose of original written disclosure, as well as for the purpose of restricting the claimed subject matter, independent of the compositions of the features in the embodiments and/or the claims. In addition, all value ranges or indications of groups of entities are intended to disclose every possible intermediate value or intermediate entity for the purpose of original written disclosure, as well as for the purpose of restricting the claimed subject matter.

A rebar tying machine disclosed herein may be configured to tie rebars with a wire. The rebar tying machine may comprises a reel holding section configured to hold a reel including the wire such that the reel is rotatable about a reel rotation axis; a reel stopper configured to be switchable between a prohibited state in which the reel is prohibited from being removed from the reel holding section and a permitted state in which the reel is permitted to be removed from the reel holding section; a first roller configured to be rotatable; a second roller configured to be rotatable, wherein the second roller is configured to be switchable between a first state in which the wire is held between the first roller and the second roller and a second state in which a distance between the first roller and the second roller is longer than a distance between the first roller and the second roller in the first state; and a twisting unit configured to twist the wire wound around the rebars by the first roller and the second roller. The second roller may be configured to switch from the first state to the second state when the reel stopper switches from the prohibited state to the permitted state.

In one or more embodiments, the wire may not be held between the first roller and the second roller when the second roller is in the second state.

The configuration above facilitates insertion of the wire in between the first roller and the second roller as well as removal of the wire from between the first roller and the second roller.

In one or more embodiments, the second roller may switch from the second state to the first state when the reel stopper switches from the permitted state to the prohibited state.

According to the configuration above, the second roller switches from the second state to the first state in response to the reel stopper switching from the permitted state to the prohibited state. This facilitates switching of the states of the second roller and switching of the states of the reel stopper.

In one or more embodiments, the reel holding section may have a reel housing space for housing the reel therein.

The configuration above prevents adhesion of liquid or dust to the reel when the reel is housed in the reel housing space.

In one or more embodiments, the rebar tying machine may further comprise a link member supporting the second roller such that the second roller is rotatable, wherein the link member is configured to switch the second roller between the first state and the second state. The reel stopper may comprise an actuation member configured to actuate the link member when the reel stopper switches from the prohibited state to the permitted state.

The configuration above allows the second roller to switch from the first state to the second state in response to the reel stopper switching from the prohibited state to the permitted state, using a simple mechanism.

In one or more embodiments, the rebar tying machine may further comprise a biasing member configured to bias the link member to switch the second roller from the second state to the first state.

The configuration above facilitates switching the second roller from the second state to the first state by the biasing force of the biasing member.

In one or more embodiments, the reel stopper may be pivotable between a first position at which the reel stopper is positioned in the prohibited state and a second position at which the reel stopper is positioned in the permitted state. The reel stopper may be configured to pivot toward the first position when the reel stopper is positioned closer to the first position than a neutral position is, which is between the first position and the second position, and pivot toward the second position when the reel stopper is positioned closer to the second position than the neutral position is.

According to the configuration above, in the course of a user pivoting the reel stopper from the first position to the second position, the user can let go of the reel stopper once having pivoted it beyond the neutral position, because after it has been pivoted past the neutral position, the reel stopper automatically pivots to the second position. Further, in the course of the user pivoting the reel stopper from the second position to the first position, the user can let go of the reel stopper once having pivoted it beyond the neutral position, because after it has been pivoted past the neutral position, the reel stopper automatically pivots to the first position.

In one or more embodiments, the actuation member may comprise a roller configured to be rotatable and contact the link member.

In the configuration above, the roller is configured to rotate while contacting the link member. This reduces the force required for the user to manipulate the reel stopper compared to a configuration in which the actuation member is not configured to rotate while contacting the link member.

In one or more embodiments, the link member may be pivotable about a link pivot axis. A distance between the link pivot axis and a position of the link member actuated by the reel stopper may be longer than a distance between the link pivot axis and a position where the link member supports the second roller.

The configuration above reduces the force required for the user to manipulate the reel stopper compared to a configuration in which the distance between a position of the link member actuated by the reel stopper and the link pivot axis is shorter than the distance between a position where the link member supports the second roller and the link pivot axis.

In one or more embodiments, the rebar tying machine may further comprise a lock lever mounted on the reel stopper and configured to be manipulated by a user. The lock lever may be configured to keep the reel stopper in the prohibited state when engaged with the reel holding section.

The configuration above allows the user to manipulate the lock lever with his/her hand manipulating the reel stopper.

In one or more embodiments, the reel stopper may be pivotable about a stopper pivot axis. The stopper pivot axis may be located above the reel rotation axis and below the second roller.

The configuration above reduces the force required for the user to manipulate the reel stopper compared to a configuration in which the stopper pivot axis is located below the reel rotation axis.

In one or more embodiments, the rebar tying machine may further comprise a reel pressing member mounted on the reel stopper; and a biasing member configured to bias the reel pressing member toward the reel when the reel stopper is in the prohibited state.

In the configuration above, the reel pressing member suppresses the reel from rattling even when the reel rotates while the reel stopper is in the prohibited state.

(First Embodiment) As shown in FIG. 1, a rebar tying machine 2 is a hand-held device. The rebar tying machine 2 is configured to tie a plurality of rebars R with a wire W. Wires with various diameters (e.g., diameters from 0.5 mm to 2.5 mm) can be used in the rebar tying machine 2 depending on the diameter of rebars to be tied. For example, a wire W with a diameter of 1.6 mm or less (e.g., 0.8 mm) may be used to tie rebars R with a small diameter of 16 mm or less (e.g., diameter of 16 mm), while a wire W with a diameter of 1.6 mm or greater (e.g., 2.0 mm) may be used to tie rebars R with a large diameter of 16 mm or greater (e.g., diameter of 25 mm or 32 mm). Hereinafter, the longitudinal direction of a twisting unit 80 (see FIG. 2) is termed a front-rear direction, a direction perpendicular to the front-rear direction is termed an up-down direction, and the direction perpendicular to the front-rear direction and the up-down direction is termed a right-left direction.

The rebar tying machine 2 comprises a main body housing 4, a reel cover 6, and a battery pack BP. The main body housing 4 comprises a right housing 8 defining the outer shape of right half of the main body housing 4 and a left housing 10 defining the outer shape of left half of the main body housing 4.

The main body housing 4 comprises a twisting unit housing section 14, a grip 16, a battery receptacle 18, a feeding unit housing section 20, and a reel holding section 22. The twisting unit housing section 14, the grip 16, the battery receptacle 18, the feeding unit housing section 20, and the reel holding section 22 are formed by the right housing 8 and the left housing 10.

As shown in FIG. 2, the twisting unit housing section 14 extends in the front-rear direction. The grip 16 is located on a lower rear portion of the twisting unit housing section 14. The grip 16 is configured to be grasped by a user.

The battery receptacle 18 is located on a lower portion of the grip 16. The battery pack BP is detachably attached to the lower end of the battery receptacle 18. For example, the battery pack BP comprises a secondary battery such as a lithium-ion battery.

The feeding unit housing section 20 is located on a lower front portion of the twisting unit housing section 14. The feeding unit housing section 20 is located forward of the grip 16.

The reel holding section 22 is located on a lower portion of the feeding unit housing section 20. In FIG. 2, the reel holding section 22 is depicted by a dashed line. The reel holding section 22 is located forward of the grip 16, the battery receptacle 18, and the battery pack BP. The reel holding section 22 is connected to the front end of the battery receptacle 18. As shown in FIG. 3, the reel holding section 22 is configured to house a reel 24. The reel 24 comprises a wire W and a bobbin 26 on which the wire W is wound.

The reel holding section 22 comprises a base 30, a cylindrical portion 32, and a projection 34. The base 30 defines a reel housing space 36. The left end of the base 30 is open.

The cylindrical portion 32 is located in the reel housing space 36. The cylindrical portion 32 extends leftward from the base 30. The cylindrical portion 32 is inserted into the bobbin 26. The reel 24 is housed in the reel housing space 36 by the cylindrical portion 32 being inserted into the bobbin 26. The cylindrical portion 32 holds the reel 24 such that the reel 24 is rotatable about a reel rotation axis AX1. The reel rotation axis AX1 extends in the right-left direction.

The projection 34 projects downward from the lower end of the base 30. The projection 34 is located outside the reel housing space 36. As shown in FIG. 4, the projection 34 comprises a vertical surface 34a and an inclined surface 34b.

The vertical surface 34a is within a plane on which the front-rear direction and the up-down direction lie. The inclined surface 34b is located on the left side of the vertical surface 34a. The inclined surface 34b is inclined relative to the vertical surface 34a.

As shown in FIG. 1, the reel cover 6 comprises a cover member 40 and an actuation member 42 (see FIG. 6). The cover member 40 is pivotably mounted on the left housing 10. In this embodiment, the cover member 40 is mounted on the feeding unit housing section 20. The cover member 40 is pivotable about a cover pivot axis AX2. The reel cover 6 is switched between a prohibited state and a permitted state (see FIG. 5) by the pivot movement of the cover member 40. The cover pivot axis AX2 is located above the battery receptacle 18 and the reel rotation axis AX1 (see FIG. 2).

As shown in FIG. 3, the reel cover 6 is positioned at a first position when in the prohibited state. In this state, the reel housing space 36 is closed by the reel cover 6. Thus, the reel 24 is prevented from being detached from the cylindrical portion 32, i.e., from moving out of the reel housing space 36. When the reel cover 6 is at the first position, the cover member 40 is in contact with the projection 34 from the left. This prevents the reel cover 6 from pivoting beyond the first position.

As shown in FIG. 5, the reel cover 6 is positioned at a second position when in the permitted state. In this state, the reel housing space 36 is opened. Thus, the reel 24 is permitted to be detached from the cylindrical portion 32 (see FIG. 3), i.e., to move out of the reel housing space 36. When the reel cover 6 is at the second position, the cover member 40 is in contact with the left housing 10. This prevents the reel cover 6 from pivoting beyond the second position.

As shown in FIG. 6, the actuation member 42 is mounted on one end of the cover member 40. The actuation member 42 is located near the cover pivot axis AX2. The actuation member 42 comprises a roller 44. The roller 44 is for example a bearing such as a needle bearing. The roller 44 pivots about the cover pivot axis AX2 with the pivot movement of the cover member 40. The roller 44 is rotatable about a center axis AX3. The center axis AX3 extends through the center of the actuation member 42. The center axis AX3 is substantially parallel to the cover pivot axis AX2

As shown in FIG. 3, the rebar tying machine 2 further comprises a reel pressing member 48, a biasing member 50, a lock lever 52, and a biasing member 54 (see FIG. 7). The reel pressing member 48 has a substantially truncated cone shape. The reel pressing member 48 is slidably mounted on the cover member 40. The biasing member 50 is held between the reel pressing member 48 and the cover member 40. The biasing member 50 biases the reel pressing member 48 in a direction away from the cover member 40.

When the reel cover 6 is at the first position, the reel pressing member 48 is partially inserted in the bobbin 26. The reel pressing member 48 is pressed against the left end of the bobbin 26 by the biasing force of the biasing member 50. The bobbin 26 is thereby held between the base 30 and the reel pressing member 48. This prevents the reel 24 from being rattled in the right-left direction during the rotation of the reel 24. During the rotation of the reel 24, the bobbin 26 slides on the outer circumferential surface of the cylindrical portion 32 and the side surface of the reel pressing member 48.

As shown in FIG. 7, the lock lever 52 is mounted on the lower end of the cover member 40. The lock lever 52 comprises a lever body 56 and an engagement portion 58.

The lever body 56 is pivotable about a lever pivot axis AX4. The lever body 56 is configured to be manipulated by the user. The biasing member 54 is held between the rear end of the lever body 56 and the cover member 40. The biasing member 54 biases the rear end of the lever body 56 in a direction away from the cover member 40. The distance between the cover pivot axis AX2 (see FIG. 6) and the lever body 56 is longer than the distance between the cover pivot axis AX2 and the actuation member 42 (see FIG. 6). This allows the user to manipulate the reel cover 6 with a small force.

The engagement portion 58 is located forward of the lever pivot axis AX4. As shown in FIG. 3, the engagement portion 58 comprises a vertical surface 58a and an inclined surface 58b.

When the reel cover 6 is at the first position, the vertical surface 58a is engaged with the vertical surface 34a of the projection 34. When the vertical surface 58a is engaged with the vertical surface 34a, the pivot movement of the reel cover 6 from the first position to the second position is prohibited.

The inclined surface 58b is inclined relative to the vertical surface 58a. As the reel cover 6 is pivoted from the second position to the first position, the inclined surface 58b contacts the inclined surface 34b of the projection 34 and then slides on the inclined surface 34b. Thereby, the lock lever 52 is pivoted such that the engagement portion 58 is moved away from the base 30. When the vertical surface 58a of the engagement portion 58 is moved rightward beyond the vertical surface 34a of the projection 34, the lock lever 52 is pivoted by the biasing force of the biasing member 54 such that the engagement portion 58 approaches the base 30 and finally returns to its initial position. Thus, the engagement portion 58 can be engaged with the projection 34 after the reel cover 6 has been pivoted to the first position, without the user manipulating the lock lever 52.

As shown in FIG. 1, the rebar tying machine 2 further comprises a main power switch 62, a display 64, a tying force increasing switch 66, a tying force reducing switch 68, a trigger 70, and a trigger switch 72 (see FIG. 2).

The main power switch 62, the display 64, the tying force increasing switch 66, and the tying force reducing switch 68 are located on a rear portion of the upper surface of the main body housing 4. The main power switch 62 is configured to receive a user's manipulation for switching the rebar tying machine 2 between an on state and an off state. The display 64 is configured to display information related to the rebar tying machine 2. When the tying force increasing switch 66 is manipulated, a setting value for the tying force on the wire W applied by the rebar tying machine 2 is increased by one level. When the tying force reducing switch 68 is manipulated, a setting value for the tying force on the wire W applied by the rebar tying machine 2 is reduced by one level. The tying force on the wire W corresponds to a force of twisting the wire W, i.e., a current value of a twisting motor 146, which will be described.

The trigger 70 is mounted on an upper portion of the front surface of the grip 16 and configured to be pulled. The trigger 70 is configured to be manipulated by the user.

As shown in FIG. 2, the trigger switch 72 is housed in the grip 16. When the trigger 70 is pulled, the trigger switch 72 is pushed by the trigger 70. In response to the trigger switch 72 being pushed while the rebar tying machine 2 is in the on state, the rebar tying machine 2 ties the rebars R with the wire W.

The rebar tying machine 2 further comprises a feeding unit 74, a guide unit 76, a cutting unit 78, a twisting unit 80, and a control unit 82.

The feeding unit 74 is housed in the feeding unit housing section 20. The feeding unit 74 is supported by the main body housing 4. As shown in FIG. 8, the feeding unit 74 comprises a feeding motor 88, a fixed base 90, a feeding guide 92, a transmission roller 94, a first roller 96, a second roller 98, a link member 100, and a biasing member 102 (see FIG. 6).

As shown in FIG. 2, the feeding motor 88 rotates using electric power supplied from the battery pack BP. The feeding motor 88 is for example a brushless motor.

The fixed base 90 is fixed to the main body housing 4. As shown in FIG. 8, the fixed base 90 supports the feeding motor 88.

The feeding guide 92 is fixed to the fixed base 90. The feeding guide 92 has a guide hole 92a penetrating the feeding guide 92 in the up-down direction. The wire W passes through the guide hole 92a.

The transmission roller 94 is located forward of the fixed base 90. The transmission roller 94 is fixed to the shaft of the feeding motor 88 via a speed reducer (not shown). The transmission roller 94 rotates with the rotation of the shaft (not shown) of the feeding motor 88. The transmission roller 94 has teeth 94a defined in its outer circumferential surface.

The first roller 96 is rotatably supported by the fixed base 90. The first roller 96 is located above the cover pivot axis AX2. The first roller 96 rotates about a first roller rotation axis AX6. The first roller 96 has teeth 96a defined in its outer circumferential surface and a groove 96b recessed into the outer circumferential surface. The teeth 96a are engaged with the teeth 94a of the transmission roller 94. Thus, the first roller 96 rotates with the rotation of the transmission roller 94. The first roller 96 corresponds to a driving roller. The groove 96b extends along the full circumference of the first roller 96.

The second roller 98 is located on the left side of the first roller 96. The second roller 98 is located above the cover pivot axis AX2. The second roller 98 has teeth 98a defined in its outer circumferential surface and a groove 98b recessed into the outer circumferential surface. The teeth 98a are configured to engage with the teeth 96a of the first roller 96. When the first roller 96 rotates with the teeth 96a engaged with the teeth 98a, the second roller 98 rotates about a second roller rotation axis AX7. Thus, the second roller 98 corresponds to a driven roller. The groove 98b extends along the full circumference of the second roller 98. When the teeth 98a and the teeth 96a are engaged with each other and the wire W is interposed between the first roller 96 and the second roller 98, the wire W is held in the grooves 96b and 98b between the first roller 96 and the second roller 98. When the first roller 96 rotates in the forward direction in this state, the wire W is drawn from the bobbin 26 (see FIG. 3) toward the guide unit 76 (see FIG. 2), whereas when the first roller 96 rotates in the reverse direction, the wire W is pulled back toward the bobbin 26.

As shown in FIG. 6, the upper end of the link member 100 supports the second roller 98 such that the second roller 98 is rotatable. The link member 100 supports the second roller 98 near the second roller rotation axis AX7 of the second roller 98. The link member 100 is pivotably supported by the fixed base 90. The link member 100 pivots about a link pivot axis AX5. The link pivot axis AX5 is located below the first roller 96 and the second roller 98 and above the cover pivot axis AX2. The link member 100 is configured to pivot between a first link position and a second link position. The link pivot axis AX5 is located below the first roller rotation axis AX6 and the second roller rotation axis AX7. As shown in FIGS. 8 and 9, the link member 100 switches the second roller 98 between a first state and a second state by pivoting between the first link position and the second link position.

As shown in FIG. 8, the second roller 98 is positioned at a first roller position when in the first state. In this state, the teeth 98a of the second roller 98 are engaged with the teeth 96a of the first roller 96. Thus, the wire W is held in the grooves 96b and 98b between the first roller 96 and the second roller 98. The first state thus corresponds to a wire holding state.

As shown in FIG. 9, the second roller 98 is positioned at a second roller position when in the second state. In this state, the distance between the first roller rotation axis AX6 and the second roller rotation axis AX7 is longer than the distance between the first roller rotation axis AX6 and the second roller rotation axis AX7 when the second roller 98 is in the first state. Thus, the distance between the first roller 96 and the second roller 98 in the second state is longer than the distance between the first roller 96 and the second roller 98 in the first state. When the second roller 98 is in the second state, the second roller 98 is separated from the first roller 96. Thus, the teeth 98a of the second roller 98 are not engaged with the teeth 96a of the first roller 96. In this state, the wire W is not held between the first roller 96 and the second roller 98. The second state thus corresponds to a wire non-holding state. In this state, the second roller 98 does not rotate with the rotation of the first roller 96. Thus, even when the wire W is interposed between the first roller 96 and the second roller 98, the wire W is not drawn toward the guide unit 76 (see FIG. 2) nor pulled back toward the bobbin 26 (see FIG. 3).

As shown in FIG. 6, the biasing member 102 is held between the lower end of the link member 100 and the fixed base 90. The biasing member 102 biases the link member 100 from the second link position toward the first link position.

In this embodiment, the link member 100 pivots between the first link position and the second link position by being moved by the reel cover 6. As shown in FIG. 8, when the reel cover 6 is at the first position, the roller 44 is separated from the link member 100. Thus, the link member 100 is at the first link position, and the second roller 98 is pressed against the first roller 96 by the link member 100 being biased by the biasing member 102 (see FIG. 6). As shown in FIG. 9, when the reel cover 6 pivots from the first position to the second position, the roller 44 pushes the lower end of the link member 100 toward the fixed base 90. The link member 100 is thereby pivoted from the first link position to the second link position. The distance between the position at which the roller 44 pushes the link member 100 and the link pivot axis AX5 is longer than the distance between the link pivot axis AX5 and the second roller rotation axis AX7. This allows for a reduction in a force required to push the link member 100 compared to a configuration in which the distance between the position at which the roller 44 pushes the link member 100 and the link pivot axis AX5 is shorter than the distance between the link pivot axis AX5 and the second roller rotation axis AX7.

As shown in FIG. 6, when the reel cover 6 is positioned closer to the second position than the neutral position between the first and second positions is, the link member 100 applies a force that pivots the reel cover 6 toward the second position onto the reel cover 6, by being biased by the biasing member 102. Thus, when the user pivots the reel cover 6 from the first position to the second position, once the reel cover 6 passes the neutral position, the reel cover 6 automatically pivots toward the second position even if the user let go of the reel cover 6. The reel cover 6 is kept at the second position by the biasing force of the biasing member 102. When the reel cover 6 is at the neutral position, a plane CP connecting the cover pivot axis AX2 and the center axis AX3 overlaps a neutral plane NP on which the front-rear direction and the right-left direction lie. As shown in FIG. 10, when the reel cover 6 is positioned closer to the first position than the neutral position is, the link member 100 applies a force that pivots the reel cover 6 toward the first position onto the reel cover 6, by being biased by the biasing member 102. Thus, when the user pivots the reel cover 6 from the second position to the first position, once the reel cover 6 passes the neutral position, the reel cover 6 automatically pivots toward the first position even if the user let go of the reel cover 6.

To replace the reel 24, as shown in FIG. 5, the user grips the reel cover 6 with a hand, pushes the lock lever 52 with the same hand gripping the reel cover 6, and then pivots the reel cover 6 from the first position to the second position. As shown in FIG. 6, the link member 100 is pivoted from the first link position to the second link position by the roller 44 pushing the lower end of the link member 100. As shown in FIG. 9, the second roller 98 is moved from the first roller position to the second roller position, and thus switches from the first state to the second state. Then, the user pulls the wire W out from between the first roller 96 and the second roller 98. As shown in FIG. 3, the user removes the reel 24 from the cylindrical portion 32 and then attaches a new reel 24 to the cylindrical portion 32. Thereafter, as shown in FIG. 9, the user inserts the wire W between the first roller 96 and the second roller 98. Finally, the user pivots the reel cover 6 from the second position to the first position. The roller 44 is thereby separated from the lower end of the link member 100 as shown in FIG. 8, and the link member 100 pivots from the second link position to the first link position. The second roller 98 is moved from the second roller position to the first roller position, and thus switches from the second state to the first state. The wire W is thereby held between the first roller 96 and the second roller 98.

As shown in FIG. 11, the guide unit 76 is supported by the main body housing 4. The guide unit 76 comprises a first guide member 110, a second guide member 112, a first pin 114, a second pin 115, and a wire guide 116. The first guide member 110 and the second guide member 112 are fixed to the front end of the twisting unit housing section 14. The first guide member 110 and the second guide member 112 extend forward from the front end of the twisting unit housing section 14. The first guide member 110 is open downward. The first guide member 110 includes a first wire passage 120 having an upwardly convex shape. The second guide member 112 is located below and separated from the first guide member 110. The rebars R are placed between the first guide member 110 and the second guide member 112 upon tying. The second guide member 112 is open upward. The second guide member 112 includes a second wire passage 122.

The first pin 114 and the second pin 115 are fixed to the first guide member 110. A part of the first pin 114 and the second pin 115 are located in the first wire passage 120. The first pin 114 is located near an exit 120a of the first wire passage 120. The second pin 115 is located near an entrance 120b of the first wire passage 120.

The wire guide 116 is fixed to the second guide member 112. The wire guide 116 is located between the feeding unit 74 and the first guide member 110. The wire guide 116 has a guide hole 116a.

The wire W from the feeding unit 74 passes through the guide hole 116a of the wire guide 116 and then proceeds to the entrance 120b of the first wire passage 120. The first guide member 110 guides the wire W to pass through the first wire passage 120 forward. While passing through the first wire passage 120, the wire W contacts the first pin 114 and the second pin 115. This gives a downward curl to the wire W. After passing the exit 120a of the first wire passage 120, the wire W proceeds to an entrance 122a of the second wire passage 122. The second guide member 112 guides the wire W to pass through the second wire passage 122 rearward. After passing an exit 122b of the second wire passage 122, the wire W proceeds rearward and upward. A loop RP of the wire W is thereby formed, and thus the wire W is wound around the rebars R. The rebars R pass through the loop RP in the right-left direction.

As shown in FIG. 2, the cutting unit 78 is housed in the twisting unit housing section 14. The cutting unit 78 is supported by the main body housing 4. The cutting unit 78 is located between the feeding unit 74 and the first guide member 110. The cutting unit 78 is located above the feeding unit 74 and the reel 24. As shown in FIG. 12, the cutting unit 78 comprises a cutter guide 126, a cutter 128, a push lever 130, a support shaft 132 (see FIG. 14), and a biasing member 134 (see FIG. 14).

The cutter guide 126 is fixed to the twisting unit housing section 14 (see FIG. 2). The cutter guide 126 has a cutter guide hole 136 and a wire guide hole 138. The cutter guide hole 136 penetrates the cutter guide 126 in the front-rear direction. As shown in FIG. 11, the wire guide hole 138 is connected to the cutter guide hole 136 near the front end of the cutter guide hole 136. The wire guide hole 138 penetrates the cutter guide 126 in the up-down direction. The wire guide hole 138 faces the guide hole 116a of the wire guide 116. The wire guide hole 138 is located between the guide hole 116a and the entrance 120b of the first wire passage 120. Thus, the wire W first passes through the guide hole 116a and then passes through the wire guide hole 138, and after that, proceeds to the entrance 120b of the first wire passage 120.

As shown in FIG. 12, the cutter 128 extends in the front-rear direction. A front portion of the cutter 128 is inserted in the cutter guide hole 136. The cutter 128 is supported by the cutter guide 126 such that it is slidable in the front-rear direction.

The push lever 130 is located rearward of the cutter guide 126. The push lever 130 is fixed to the cutter 128. The push lever 130 comprises a first lever portion 140 and a second lever portion 142. The first lever portion 140 is located at the front end of the push lever 130. As shown in FIG. 13, when the first lever portion 140 is pushed forward by the twisting unit 80, the push lever 130 is moved toward the cutter guide 126. Thereby, the cutter 128 slides forward beyond the wire guide hole 138. As a result, the wire W is cut by the cutter 128 and the cutter guide 126.

The second lever portion 142 is located at the rear end of the push lever 130. When the second lever portion 142 is pushed rearward by the twisting unit 80, the push lever 130 is moved away from the cutter guide 126.

As shown in FIG. 14, the support shaft 132 extends in the front-rear direction. The support shaft 132 is located next to the cutter 128 in the right-left direction. The rear end of the support shaft 132 is fixed to the push lever 130. A front portion of the support shaft 132 is slidably supported by the cutter guide 126. The support shaft 132 prevents rotation of the push lever 130.

The biasing member 134 is held between the cutter guide 126 and the push lever 130. The support shaft 132 is inserted in the biasing member 134. The biasing member 134 biases the push lever 130 rearward toward its initial position. As shown in FIG. 2, the twisting unit 80 is housed in the twisting unit housing section 14. The twisting unit 80 is supported by the main body housing 4. The twisting unit 80 is located above the cutting unit 78. In the up-down direction, the twisting unit 80 is located between the first guide member 110 and the second guide member 112. As shown in FIG. 14, the twisting unit 80 comprises a twisting motor 146, a speed reducer 148, a screw shaft 150, a sleeve unit 152, a push plate 154, and a holding unit 156.

The twisting motor 146 is for example a brushless motor. The twisting motor 146 rotates about a center axis AX8 using the electric power supplied from the battery pack BP. The center axis AX8 extends in the front-rear direction. The speed reducer 148 comprises a planetary gear mechanism. The rotation of the twisting motor 146 is transmitted to the screw shaft 150 via the speed reducer 148. Thereby, the screw shaft 150 rotates about the center axis AX8.

The screw shaft 150 is inserted in the sleeve unit 152. When the screw shaft 150 rotates, the sleeve unit 152 cooperates with a rotation limiting mechanism (not shown) to move in the front-rear direction or rotate about the center axis AX8.

The push plate 154 is rotatably supported by the sleeve unit 152. The push plate 154 has a substantially flat plate shape. The push plate 154 moves together with the sleeve unit 152 in the front-rear direction. The push plate 154 pushes the first lever portion 140 forward when moving forward, whereas the push plate 154 pushes the second lever portion 142 rearward when moving rearward. The push plate 154 does not rotate together with the sleeve unit 152.

The holding unit 156 extends forward from a front portion of the sleeve unit 152. The holding unit 156 is located rearward of the rebars R (see FIG. 11). The holding unit 156 comprises a clamp shaft 160, a right clamp 162, and a left clamp 164.

The clamp shaft 160 is inserted in the sleeve unit 152 from the front end of the sleeve unit 152. The clamp shaft 160 is located on the center axis AX8.

The right clamp 162 is mounted on the clamp shaft 160 and penetrates the clamp shaft 160 from the right. The right clamp 162 is movable in the right-left direction relative to the clamp shaft 160. When the right clamp 162 is in its initial state, the right clamp 162 is positioned farthest away from the clamp shaft 160 on the right side of the clamp shaft 160. In this state, a right wire passage 165 is formed between the right clamp 162 and the clamp shaft 160. The wire W can pass through the right wire passage 165. As the sleeve unit 152 moves forward, the right clamp 162 moves leftward toward the clamp shaft 160. Finally, one end of the wire W is held between the right clamp 162 and the clamp shaft 160.

The left clamp 164 is mounted on the clamp shaft 160 and penetrates the clamp shaft 160 from the left. The left clamp 164 is movable in the right-left direction relative to the clamp shaft 160. When the left clamp 164 is in its initial state, the left clamp 164 is positioned farthest away from the clamp shaft 160 on the left side of the clamp shaft 160. In this state, a left wire passage 166 is formed between the left clamp 164 and the clamp shaft 160. The wire W can pass through the left wire passage 166. As the sleeve unit 152 moves forward, the left clamp 164 moves rightward toward the clamp shaft 160. Finally, another end of the wire W is held between the left clamp 164 and the clamp shaft 160.

When the sleeve unit 152 rotates with the one end and the other end of the wire W held by the holding unit 156, the holding unit 156 rotates about the center axis AX8. The wire W is thereby twisted, and thus the rebars R (see FIG. 2) are tied with the wire W.

As shown in FIG. 2, the control unit 82 is housed in the battery receptacle 18. The control unit 82 comprises an MCU (not shown) and switching elements (not shown). The control unit 82 is electrically connected to the main power switch 62 (see FIG. 1), the display 64 (see FIG. 1), the tying force increasing switch 66 (see FIG. 1), the tying force reducing switch 68 (see FIG. 1), the trigger switch 72, the feeding motor 88, the twisting motor 146, and the battery pack BP.

As shown in FIG. 15, the rebar tying machine 2 comprises a pair of side plates 168, a pair of slide units 170, and a pair of detection sensors 172 (see FIG. 16). One slide unit 170 and one detection sensor 172 are assigned to one side plate 168.

The pair of side plates 168 are mounted on the front end of the twisting unit housing section 14. The pair of side plates 168 are pressed against the rebars R when the rebars R are tied with the wire W. One of the side plates 168 is mounted on the right housing 8 such that the side plate 168 can open and close. The other side plate 168 is mounted on the left housing 10 such that the side plate 168 can open and close. As shown in FIG. 2, the side plates 168 are typically closed by the biasing force of biasing members 174. The holding unit 156 is located rearward of the side plates 168.

The slide units 170 and the detection sensors 172 are located inside the twisting unit housing section 14. The slide units 170 and the detection sensors 172 are located above the twisting unit 80. As shown in FIG. 16, each slide unit 170 comprises a slide plate 178, a magnet holding member 180, a magnet 182, and a biasing member 184.

The slide plate 178 extends in the front-rear direction. The slide plate 178 is supported by the twisting unit housing section 14 (see FIG. 2) such that it is slidable in the front-rear direction. The slide plate 178 is in contact with the rear surface of the side plate 168.

The magnet holding member 180 is fixed to the rear end of the slide plate 178. The magnet holding member 180 holds the magnet 182. The magnet 182 is for example a permanent magnet. The magnet holding member 180 is biased forward by the biasing member 184. The slide plate 178 is thereby pressed against the side plate 168.

The detection sensors 172 are electrically connected to the control unit 82 (see FIG. 2). Each detection sensor 172 comprises a sensor board 186 and a sensor element 188. The sensor board 186 is fixed to the twisting unit housing section 14 (see FIG. 2). The sensor element 188 is mounted on the sensor board 186. The sensor element 188 is a magnetic sensor element. When the side plate 168 is closed, the sensor element 188 faces the magnet 182, whereas when the side plate 168 is opened, the sensor element 188 does not face the magnet 182. In FIG. 16, the position of the magnet holding member 180 and the magnet 182 when the side plate 168 is opened is depicted by a dotted line. The detection sensor 172 detects opening and closing of the side plate 168 by the sensor element 188 detecting a magnetic change of the magnet 182.

As shown in FIG. 17, the rebar tying machine 2 further comprises a bending member 192. The bending member 192 is housed in the twisting unit housing section 14. The bending member 192 has a plate shape. The bending member 192 is located along a plane on which the front-rear direction and the up-down direction lie. For example, the bending member 192 is constituted of a metal material. The bending member 192 is a separate component from the twisting unit 80. The bending member 192 is fixed to the second guide member 112. Thus, the bending member 192 is immovable relative to the main body housing 4. The left surface of the bending member 192 defines a part of the second wire passage 122 of the second guide member 112. The bending member 192 is located near the wire guide hole 138. The bending member 192 is located leftward of the wire guide hole 138. The bending member 192 is located rightward of the second wire passage 122. Thus, in the right-left direction, the bending member 192 is located between the wire guide hole 138 and the second wire passage 122.

The bending member 192 comprises a contact surface 194. The contact surface 194 is a part of the upper surface of the bending member 192. The contact surface 194 connects the right surface of the bending member 192 to the left surface thereof. The width of the contact surface 194 in the right-left direction gradually increases from the rear end of the contact surface 194 toward an inflexion point and is constant from the inflexion point to the front end of the contact surface 194. The width of the contact surface 194 in the right-left direction is gradually narrowed upward. The contact surface 194 extends downward and rightward from the upper left end of the bending member 192. The contact surface 194 is oriented upward and rightward.

As shown in FIG. 18, the contact surface 194 is located forward of the cutter 128 (closer to the rebars R than the cutter 128 is). The contact surface 194 is located above the wire guide hole 138 and below the holding unit 156. Thus, in the up-down direction, the contact surface 194 is located between the wire guide hole 138 and the holding unit 156. When the rebar tying machine 2 is viewed in a direction perpendicular to the center axis AX8, the contact surface 194 is inclined relative to the center axis AX8. The contact surface 194 is inclined such that its rear end is closest to the center axis AX8 and its front end is farthest from the center axis AX8. The front end of the contact surface 194 is farther from the center axis AX8 than the rear end thereof is. The contact surface 194 is curved.

The control unit 82, which is shown in FIG. 2, executes the process shown in FIG. 19 upon when the main power switch 62 (see FIG. 1) is manipulated for the first time after the reel 24 has been attached to the reel holding section 22.

As shown in FIG. 19, in S2, the control unit 82 executes an initialization process. Specifically, the control unit 82 repeats a feeding process and a cutting process. In the feeding process, the control unit 82 rotates the feeding motor 88 in the forward direction by a predetermined number of rotations. The first roller 96 is thereby rotated in the forward direction, and thus the wire W is drawn toward the guide unit 76. In the cutting process, the control unit 82 rotates the twisting motor 146 in the forward direction by a predetermined number of rotations, and then rotates the twisting motor 146 in the reverse direction by a predetermined number of rotations. First, when the sleeve unit 152 moves forward, the push plate 154 pushes the first lever portion 140 forward. The push lever 130 is thereby moved forward and the cutter 128 is moved forward beyond the wire guide hole 138. Then, when the sleeve unit 152 moves rearward, the push lever 130 returns to its initial position by being biased rearward by the biasing member 134. When determining that a current value of the twisting motor 146 has decreased after it had reached or exceeded a predetermined value during the cutting process, the control unit 82 terminates the initialization process after the completion of the cutting process. The decrease in the current value of the twisting motor 146 after it reached or exceeded the predetermined value means that the wire W has been cut by the cutter 128. At the end of the initialization process, a leading end W1 of the wire W is positioned in the wire guide hole 138.

In S4, the control unit 82 executes a wire prior-feeding process. Specifically, the control unit 82 rotates the feeding motor 88 in the forward direction by a reference number of rotations. As shown in FIG. 20, the rotation of the first roller 96 in the forward direction causes the leading end W1 of the wire W to move from the wire guide hole 138 to a first position. The first position is closer to the exit 120a of the first wire passage 120 than the wire guide hole 138 and the cutter 128 are. The first position is in the first wire passage 120. The first position is at the exit 120a of the first wire passage 120. The first position is not beyond the exit 120a of the first wire passage 120 toward the entrance 122a of the second wire passage 122.

In S6, the control unit 82 sets the number of rotations of the feeding motor 88 for a winding process (which will be described later) to be a first number of rotations. When the feeding motor 88 rotates in the forward direction by the first number of rotations, the first roller 96 rotates in the forward direction and the leading end W1 of the wire W is thereby moved from the first position to the left wire passage 166.

After executing the process shown in FIG. 19, the control unit 82 executes the process shown in FIGS. 21 and 22.

As shown in FIG. 21, the control unit 82 determines in S20 whether the trigger 70 has been pulled. When the control unit 82 determines that the trigger 70 has been pulled (YES in S20), the process proceeds to S22.

In S22, the control unit 82 determines whether the trigger 70 has been pulled for the first time after the initialization process. When the control unit 82 determines that the trigger 70 has been pulled for the first time after the initialization process (YES in S22), the process proceeds to S30 in FIG. 22, whereas when the control unit 82 does not determine that the trigger 70 has been pulled for the first time after the initialization process (NO in S22), the process proceeds to S24.

S24 corresponds to the process shown in FIGS. 21 and 22 that is executed the second time or more after the initialization process. In S24, the control unit 82 determines whether the side plates 168 were opened and closed in the process shown in FIGS. 21 and 22 that was executed the last time. When the control unit 82 determines that the side plates were opened and closed (YES in S24), the process proceeds to S30 in FIG. 22, whereas when the control unit 82 determines that the side plates 168 were not opened nor closed (NO in S24), the process proceeds to S26.

In S26, the control unit 82 rotates the twisting motor 146 in the reverse direction to return the twisting unit 80 to its initial position. After this, the process proceeds to S30 in FIG. 22.

As shown in FIG. 22, the control unit 82 executes a tying process in S30. Specifically, the tying process comprises a winding process, a first holding process, a pullback process, a second holding process, a cutting process, a twisting process, a bending process, and a wire releasing process.

(Winding Process) The control unit 82 rotates the feeding motor 88 in the forward direction. Thereby, as shown in FIG. 11, the first roller 96 is rotated in the forward direction, and the leading end W1 of the wire W passes through the wire guide hole 138, the right wire passage 165, the first wire passage 120, the second wire passage 122, and the left wire passage 166 in this order. The loop RP of the wire W is thereby formed, and thus the wire W is wound around the rebars R. In this state, the rebars R pass through the loop RP in the right-left direction. Further, the wire W has a downward curl formed by the first pin 114 and the second pin 115 while the wire W was passing through the first wire passage 120.

(First Holding Process) The first holding process is executed after the winding process. The first holding process is executed after 0.10 seconds from the start of the tying process. The control unit 82 rotates the twisting motor 146 in the forward direction. As the sleeve unit 152, which is shown in FIG. 14, moves forward, the left clamp 164 moves rightward toward the clamp shaft 160. The left wire passage 166 is thereby narrowed, and the leading end W1 of the wire W is finally held between the left clamp 164 and the clamp shaft 160. Thus, the leading end W1 of the wire W is held by the holding unit 156.

(Pullback Process) The pullback process is executed after the first holding process. The pullback process is executed after 0.17 seconds from the start of the tying process. The control unit 82 rotates the feeding motor 88 in the reverse direction. As shown in FIG. 11, the first roller 96 is thereby rotated in the reverse direction and the wire W is pulled back toward the bobbin 26. The diameter of the loop RP of the wire W is thereby reduced, and the wire W finally contacts the rebars R. In FIG. 11, the loop RP of the wire W with reduced diameter is depicted by a dashed line.

(Second Holding Process) The second holding process is executed after the pullback process. The second holding process is executed after 0.24 seconds from the start of the tying process. The control unit 82 rotates the twisting motor 146 in the forward direction. As the sleeve unit 152, which is shown in FIG. 14, moves forward, the right clamp 162 moves leftward toward the clamp shaft 160. The right wire passage 165 is thereby narrowed, and the wire W is finally held between the right clamp 162 and the clamp shaft 160 at a position between the wire guide hole 138 and the first wire passage 120. Thus, the wire W is held by the holding unit 156 at two points.

(Cutting Process) The cutting process is executed after the second holding process. The cutting process is executed after 0.27 seconds from the start of the tying process. The control unit 82 rotates the twisting motor 146 further in the forward direction. As shown in FIG. 13, as the sleeve unit 152 moves further forward, the push plate 154 pushes the first lever portion 140 forward. The cutter 128 is thereby moved forward beyond the wire guide hole 138. As a result, the wire W is cut by the cutter 128 and the cutter guide 126 at a position between the wire guide hole 138 and the right wire passage 165. Hereinafter, the end of the wire W formed by the cutter 128 cutting the wire W may be termed as a terminal end W2 of the wire W.

(Twisting Process, Bending Process) The twisting process is executed after the cutting process. The twisting process is executed after 0.31 seconds from the start of the tying process. The bending process is executed during the twisting process. The control unit 82 rotates the twisting motor 146 further in the forward direction. When the sleeve unit 152 and the holding unit 156 rotate, the wire W is thereby twisted. Thus, the rebars R are tied with the wire W. As shown in FIG. 18, while the wire W is being twisted, the terminal end W2 of the wire W contacts the contact surface 194 and then slides thereon. Thereby, the terminal end W2 of the wire W is bent toward the rebars R. In FIG. 18, the bent terminal end W2 of the wire W is depicted by a dashed line and the wire W is exaggerated. As shown in FIG. 23, a height L1 which indicates the maximum distance between a rebar R and the terminal end W2 of the wire W is less than a height L2 between the rebar R and an unbent terminal end W2 of the wire W.

(Wire Releasing Process) The wire releasing process is executed after the twisting process. The wire releasing process is executed after 0.41 seconds from the start of the tying process. The control unit 82 rotates the twisting motor 146 in the reverse direction. As the sleeve unit 152 moves rearward, the right clamp 162 moves rightward away from the clamp shaft 160 and the left clamp 164 moves leftward away from the clamp shaft 160. The leading end W1 and the terminal end W2 of the wire W are thereby released from the holding unit 156. The wire releasing process is completed after 0.48 seconds from the start of the tying process.

As shown in FIG. 22, in S32, the control unit 82 determines whether the side plates 168 have been opened and closed. As shown in FIG. 15, the user separates the rebar tying machine 2 from the rebars R after the tying of the rebars R has been completed. Thus, after the side plates 168 are opened by the leading end W1 and the terminal end W2 of the wire W contacting the side plates 168, the side plates 168 are closed by the leading end W1 and the terminal end W2 of the wire W separating from the side plates 168. The control unit 82 determines that the side plates 168 have been opened and closed based on magnetic changes of the magnets 182 detected by the sensor elements 188 of the detection sensors 172. When the control unit 82 determines that the side plates 168 have not been opened and closed within a predetermined time period (NO in S32), the process proceeds to S34, whereas when the control unit 82 determines that the side plates 168 have been opened and closed (YES in S32), the process proceeds to S36.

In S34, the control unit 82 sets the number of rotations of the feeding motor 88 for the next winding process to be a second number of rotations. The second number of rotations is larger than the first number of rotations. When the feeding motor 88 rotates in the forward direction by the second number of rotations, the first roller 96 is thereby rotated in the forward direction and the leading end W1 of the wire W is moved from the wire guide hole 138 to the left wire passage 166. After this, the process returns to S20.

In S36, the control unit 82 rotates the twisting motor 146 in the reverse direction to return the twisting unit 80 to its initial position.

In S38, the control unit 82 executes a wire prior-feeding process. Thereby, the leading end W1 of the wire W is moved to the first position, i.e., to the exit 120a of the first wire passage 120.

In S40, the control unit 82 determines whether the trigger 70 is pulled during the wire prior-feeding process. When the control unit 82 determines that the trigger 70 is not pulled during the wire prior-feeding process (NO in S40), the process proceeds to S42, whereas when the control unit 82 determines that the trigger 70 is pulled during the wire prior-feeding process (YES in S40), the process proceeds to S44.

In S42, the control unit 82 sets the number of rotations of the feeding motor 88 to be the first number of rotations. After this, the process returns to S20.

In S44, the control unit 82 sets the number of rotations of the feeding motor 88 to be the first number of rotations. After this, the process returns to S30. The control unit 82 executes S44 and S30 almost simultaneously. Thus, after S38, the wire W is wound around the rebars R without stopping the feeding motor 88.

(Effects) The rebar tying machine 2 according to this embodiment is configured to tie the rebars R with the wire W. The rebar tying machine 2 comprises the reel holding section 22 configured to hold the reel 24 including the wire W such that the reel 24 is rotatable about the reel rotation axis AX1; the reel cover 6 (an example of reel stopper) configured to be switchable between the prohibited state in which the reel 24 is prohibited from being removed from the reel holding section 22 and the permitted state in which the reel 24 is permitted to be removed from the reel holding section 22; the first roller 96 configured to be rotatable; the second roller 98 configured to be rotatable, wherein the second roller 98 is configured to be switchable between the first state in which the wire W is held between the first roller 96 and the second roller 98 and the second state in which the distance between the first roller 96 and the second roller 98 is longer than the distance between the first roller 96 and the second roller 98 in the first state; and the twisting unit 80 configured to twist the wire W wound around the rebars R by the first roller 96 and the second roller 98. The second roller 98 is configured to switch from the first state to the second state when the reel cover 6 switches from the prohibited state to the permitted state.

According to the configuration above, the second roller 98 switches from the first state to the second state in response to the reel cover 6 switching from the prohibited state to the permitted state. This facilitates switching of the states of the second roller 98 and switching of the states of the reel cover 6.

The wire W is not held between the first roller 96 and the second roller 98 when the second roller 98 is in the second state.

The configuration above facilitates insertion of the wire W in between the first roller 96 and the second roller 98 as well as removal of the wire W from between the first roller 96 and the second roller 98.

The second roller 98 switches from the second state to the first state when the reel cover 6 switches from the permitted state to the prohibited state.

According to the configuration above, the second roller 98 switches from the second state to the first state in response to the reel cover 6 switching from the permitted state to the prohibited state. This facilitates switching of the states of the second roller 98 and switching of the states of the reel cover 6.

The reel holding section 22 has the reel housing space 36 for housing the reel 24 therein.

The configuration above prevents adhesion of liquid or dust to the reel 24 when the reel 24 is housed in the reel housing space 36.

The rebar tying machine 2 further comprises the link member 100 supporting the second roller 98 such that the second roller 98 is rotatable, wherein the link member 100 is configured to switch the second roller 98 between the first state and the second state. The reel cover 6 comprises the actuation member 42 configured to actuate the link member 100 when the reel cover 6 switches from the prohibited state to the permitted state.

The configuration above allows the second roller 98 to switch from the first state to the second state in response to the reel cover 6 switching from the prohibited state to the permitted state, using a simple mechanism.

The rebar tying machine 2 further comprises the biasing member 102 configured to bias the link member 100 to switch the second roller 98 from the second state to the first state.

The configuration above facilitates switching the second roller 98 from the second state to the first state by the biasing force of the biasing member 102.

The reel cover 6 is pivotable between the first position at which the reel cover 6 is positioned in the prohibited state and the second position at which the reel cover 6 is positioned in the permitted state. The reel cover 6 is configured to pivot toward the first position when the reel cover 6 is positioned between the first position and the neutral position, which is between the first position and the second position, and pivot toward the second position when the reel cover 6 is positioned between the second position and the neutral position.

According to the configuration above, in the course of the user pivoting the reel cover 6 from the first position to the second position, the user can let go of the reel cover 6 once having pivoted it beyond the neutral position, because after having been pivoted past the neutral position, the reel cover 6 automatically pivots to the second position. Further, in the course of the user pivoting the reel cover 6 from the second position to the first position, the user can let go of the reel cover 6 once having pivoted it beyond the neutral position, because after having been pivoted past the neutral position, the reel cover 6 automatically pivots to the first position.

The actuation member 42 comprises the roller 44 configured to be rotatable and contact the link member 100.

In the configuration above, the roller 44 is configured to rotate while contacting the link member 100. This reduces the force required for the user to manipulate the reel cover 6 compared to a configuration in which the actuation member 42 is not configured to rotate while contacting the link member 100.

The link member 100 is pivotable about the link pivot axis AX5. The distance between a position of the link member 100 actuated by the reel cover 6 and the link pivot axis AX5 is longer than the distance between the position where the link member 100 supports the second roller 98 and the link pivot axis AX5.

The configuration above reduces the force required for the user to manipulate the reel cover 6 compared to a configuration in which the distance between the position of the link member 100 actuated by the reel cover 6 and the link pivot axis AX5 is shorter than the distance between the position where the link member 100 supports the second roller 98 and the link pivot axis AX5.

The rebar tying machine 2 further comprises the lock lever 52 mounted on the reel cover 6 and configured to be manipulated by the user. The lock lever 52 is configured to keep the reel cover 6 in the prohibited state when engaged with the reel holding section 22.

The configuration above allows the user to manipulate the lock lever 52 with his/her hand manipulating the reel cover 6.

The reel cover 6 is pivotable about the cover pivot axis AX2 (an example of stopper pivot axis). The cover pivot axis AX2 is located above the reel rotation axis AX1 and below the second roller 98.

The configuration above reduces the force required for the user to manipulate the reel cover 6 compared to a configuration in which the cover pivot axis AX2 is located below the reel rotation axis AX1.

The rebar tying machine 2 further comprises the reel pressing member 48 mounted on the reel cover 6; and the biasing member 50 configured to bias the reel pressing member 48 toward the reel 24 when the reel cover 6 is in the prohibited state.

In the configuration above, the reel pressing member 48 suppresses the reel 24 from rattling even when the reel 24 rotates while the reel cover 6 is in the prohibited state.

The rebar tying machine 2 according to this embodiment is configured to tie the rebars R with the wire W. The rebar tying machine 2 comprises the reel holding section 22 configured to hold the reel 24 including the wire W such that the reel 24 is rotatable about the reel rotation axis AX1; the reel cover 6 (an example of reel stopper) configured to be switchable between the prohibited state in which the reel 24 is prohibited from being removed from the reel holding section 22 and the permitted state in which the reel 24 is permitted to be removed from the reel holding section 22; and the lock lever 52 configured to keep the reel cover 6 in the prohibited state when engaged with the reel holding section 22. The lock lever 52 is configured to engage with the reel holding section 22 without being manipulated by the user after the reel cover 6 has switched from the permitted state to the prohibited state.

According to the configuration above, the user does not have to manipulate the lock lever 52 after the reel cover 6 has switched from the permitted state to the prohibited state. Thus, a manipulation to keep the reel cover 6 in the prohibited state is less complex.

(Second Embodiment) For a second embodiment, differences from the first embodiment are described. As shown in FIG. 24, the shape of a rebar tying machine 2 according to the second embodiment is different from the shape of the rebar tying machine 2 according to the first embodiment.

As shown in FIG. 25, the control unit 82 is housed in the twisting unit housing section 14. In FIG. 25, the reel cover 6 is opened. The control unit 82 is located below the twisting unit 80. The cutting unit 78 is located above the twisting unit 80. The grip 16 is located below the twisting unit housing section 14. The battery receptacle 18 is located on the lower portion of the grip 16. The feeding unit housing section 20 is located rightward of the twisting unit housing section 14 and above the grip 16. The reel holding section 22 is located rearward of the twisting unit housing section 14 and the feeding unit housing section 20 and above the grip 16. The reel 24 is located rearward of the feeding unit 74, the guide unit 76, the cutting unit 78, and the twisting unit 80. The feeding unit 74 draws the wire W forward from the bobbin 26.

As shown in FIG. 26, the cutting unit 78 comprises a link member 226, a fixed cutter 228, and a movable cutter 230. The link member 226 moves the movable cutter 230 according to the movement of the twisting unit 80 (see FIG. 25).

The fixed cutter 228 is fixed to the first guide member 110. The fixed cutter 228 is located in the first wire passage 120. The fixed cutter 228 has a first wire guide hole 234. The first wire guide hole 234 is a through hole. The wire W can pass through the first wire guide hole 234.

The movable cutter 230 is supported by the fixed cutter 228. The fixed cutter 228 is inserted in the movable cutter 230. The movable cutter 230 is partially located in the first wire passage 120. The movable cutter 230 is connected to the link member 226. The movable cutter 230 pivots about the fixed cutter 228 by being moved by the link member 226. The wire W is thereby cut by the fixed cutter 228 and the movable cutter 230. The leading end W1 of the wire W formed by the cut of the wire W is positioned in the first wire passage 120. When the control unit 82 executes the wire prior-feeding process, the leading end W1 of the wire W is moved from the first wire guide hole 234 to the exit 120a of the first wire passage 120.

(Third Embodiment) For a third embodiment, differences from the first embodiment are described. In the third embodiment, starting times of the respective processes of the tying process are different from those of the first embodiment. The control unit 82 rotates the feeding motor 88 at a faster rotational speed than that of the feeding motor 88 in the first embodiment. Further, the control unit 82 rotates the twisting motor 146 at a faster rotational speed than that of the twisting motor 146 in the first embodiment.

The first holding process is executed after 0.09 seconds from the start of the tying process. The pullback process is executed after 0.14 seconds from the start of the tying process. The second holding process is executed after 0.20 seconds from the start of the tying process. The cutting process is executed after 0.23 seconds from the start of the tying process. The twisting process is executed after 0.26 seconds from the start of the tying process. The wire releasing process is executed after 0.34 seconds from the start of the tying process. The wire releasing process is completed after 0.40 seconds from the start of the tying process.

(Fourth Embodiment) For a fourth embodiment, differences from the first embodiment are described. In the fourth embodiment, starting times of the respective processes of the tying process are different from those of the first embodiment. The control unit 82 rotates the feeding motor 88 at a faster rotational speed than that of the feeding motor 88 in the first embodiment. Further, the control unit 82 rotates the twisting motor 146 at a faster rotational speed than that of the twisting motor 146 in the first embodiment.

The first holding process is executed after 0.08 seconds from the start of the tying process. The pullback process is executed after 0.13 seconds from the start of the tying process. The second holding process is executed after 0.18 seconds from the start of the tying process. The cutting process is executed after 0.20 seconds from the start of the tying process. The twisting process is executed after 0.23 seconds from the start of the tying process. The wire releasing process is executed after 0.30 seconds from the start of the tying process. The wire releasing process is completed after 0.35 seconds from the start of the tying process.

(Fifth Embodiment) For a fifth embodiment, differences from the first embodiment are described. In the fifth embodiment, starting times of the respective processes of the tying process are different from those of the first embodiment. The control unit 82 rotates the feeding motor 88 at a faster rotational speed than that of the feeding motor 88 in the first embodiment. Further, the control unit 82 rotates the twisting motor 146 at a faster rotational speed than that of the twisting motor 146 in the first embodiment.

The first holding process is executed after 0.06 seconds from the start of the tying process. The pullback process is executed after 0.11 seconds from the start of the tying process. The second holding process is executed after 0.15 seconds from the start of the tying process. The cutting process is executed after 0.17 seconds from the start of the tying process. The twisting process is executed after 0.19 seconds from the start of the tying process. The wire releasing process is executed after 0.26 seconds from the start of the tying process. The wire releasing process is completed after 0.30 seconds from the start of the tying process.

(Sixth Embodiment) For a sixth embodiment, differences from the first embodiment are described. As shown in FIG. 27, in the sixth embodiment, the position of the bending member 192 is different from that of the first embodiment.

The bending member 192 is located rightward of the holding unit 156. The bending member 192 is fixed to the main body housing 4. The contact surface 194 is a part of the upper surface of the bending member 192.

In a variant of the sixth embodiment, the bending member 192 may be located leftward of the holding unit 156, as depicted in FIG. 27 by a dashed line. In this case, the contact surface 194 may be a part of the lower surface of the bending member 192.

In another variant of the sixth embodiment, the bending member 192 may be located above the holding unit 156, as depicted in FIG. 27 by a dashed line. In this case, the contact surface 194 may be a part of the lower surface of the bending member 192.

(Seventh Embodiment) For a seventh embodiment, differences from the first embodiment are described. As shown in FIG. 28, in the seventh embodiment, the shape of the bending member 192 is different from that of the first embodiment.

The bending member 192 has a cylindrical shape. The bending member 192 is fixed to the main body housing 4. The bending member 192 surrounds the holding unit 156. The contact surface 194 is a part of the inner circumferential surface of the bending member 192.

(Eighth Embodiment) For an eighth embodiment, differences from the first embodiment are described. As shown in FIG. 29, the feeding unit 74 comprises a slide member 300, a support member 302, a biasing member 304, and an actuation member 306.

The slide member 300 is slidably supported by the support member 302.

The support member 302 is fixed to the fixed base 90.

The biasing member 304 is held between the lower end of the link member 100 and the slide member 300. The biasing member 304 biases the slide member 300 in a direction away from the link member 100.

One end of the actuation member 306 is connected to the actuation member 42 of the reel cover 6. The other end of the actuation member 306 is connected to the slide member 300. The actuation member 306 slides the slide member 300 as the reel cover 6 pivots between the first position and the second position.

When the reel cover 6 is at the first position, the slide member 300 is at a first slide position. When the reel cover 6 is at the first position, the second roller 98 is in the first state. As shown in FIG. 30, as the reel cover 6 pivots from the first position to the second position, the slide member 300 is slid, by the actuation member 306, in the direction away from the lower end of the link member 100 from the first slide position to a second slide position. The pivot movement of the reel cover 6 from the first position to the second position causes the second roller 98 to switch from a first pressed state to a second pressed state. The position of the link member 100 does not change due to the pivot movement of the reel cover 6 from the first position to the second position. The distance between the lower end of the link member 100 and the slide member 300 at the second slide position is greater than the distance between the lower end of the link member 100 and the slide member 300 at the first slide position. The biasing force of the biasing member 304 against the slide member 300 at the second slide position is less than the biasing force of the biasing member 304 against the slide member 300 at the first slide position. The pressing force with which the second roller 98 in the second pressed state is pressed against the first roller 96 is less than the pressing force with which the second roller 98 in the first pressed state is pressed against the first roller 96. Thus, a force for holding the wire W between the first roller 96 and the second roller 98 in the second pressed state is less than a force for holding the wire W between the first roller 96 and the second roller 98 in the first pressed state. Thus, the wire W can be inserted to between the first roller 96 and the second roller 98 more easily when the second roller 98 is in the second pressed state than when the second roller 98 is in the first pressed state.

As shown in FIG. 29, as the reel cover 6 pivots from the second position to the first position, the slide member 300 is slid, by the actuation member 306, toward the lower end of the link member 100 from the second slide position to the first slide position. The second roller 98 is thereby switched from the second pressed state to the first pressed state.

(Effects) The rebar tying machine 2 according to this embodiment is configured to tie the rebars R with the wire W. The rebar tying machine 2 comprises the reel holding section 22 configured to hold the reel 24 including the wire W such that the reel 24 is rotatable about the reel rotation axis AX1; the reel cover 6 (an example of reel stopper) configured to be switchable between the prohibited state in which the reel 24 is prohibited from being removed from the reel holding section 22 and the permitted state in which the reel 24 is permitted to be removed from the reel holding section 22; the first roller 96 configured to be rotatable; the second roller 98 configured to be rotatable, wherein the second roller 98 is configured to be switchable between the first pressed state (an example of first state) in which the wire W is held between the first roller 96 and the second roller 98 and the second pressed state (an example of second state) in which a force for holding the wire W between the first roller 96 and the second roller 98 is smaller than a force for holding the wire W between the first roller 96 and the second roller 98 in the first state; and the twisting unit 80 configured to twist the wire W wound around the rebars R by the first roller 96 and the second roller 98. The second roller 98 switches from the first pressed state to the second pressed state when the reel cover 6 switches from the prohibited state to the permitted state.

According to the configuration above, the second roller 98 switches from the first pressed state to the second pressed state in response to the reel cover 6 switching from the prohibited state to the permitted state. Further, since in the second pressing state, the force for holding the wire W between the first roller 96 and the second roller 98 is smaller than the force for holding the wire W between the first roller 96 and the second roller 98 in the first pressed state, the wire W can be easily inserted into between the first roller 96 and the second roller 98. This facilitates exchange of the reel.

(Ninth Embodiment) For a ninth embodiment, differences from the first embodiment are described. As shown in FIG. 31, the rebar tying machine 2 further comprises a pushable member 400. The pushable member 400 is swingably supported by the main body housing 4. The pushable member 400 is located near the first guide member 110. The pushable member 400 is configured to be pushed by the rebars R (see FIG. 11) positioned between the first guide member 110 and the second guide member 112.

The control unit 82 (see FIG. 2) executes the tying process in S30 of FIG. 22 in response to the pushable member 400 being pushed by the rebars R while the trigger 70 (see FIG. 2) is being pulled.

(Tenth Embodiment) For a tenth embodiment, differences from the ninth embodiment are described. In the tenth embodiment, the rebar tying machine 2 does not comprise the trigger 70 (see FIG. 2). The control unit 82 (see FIG. 2) executes the tying process in S30 of FIG. 22 in response to the pushable member 400 being pushed by the rebars R.

(Eleventh Embodiment) For an eleventh embodiment, differences from the first embodiment are described. In the eleventh embodiment, in the wire prior-feeding processes in S4 of FIGS. 19 and S38 of FIG. 22, the control unit 82 first rotates the feeding motor 88 in the forward direction by the second number of rotations. Thereby, the leading end W1 of the wire W is moved to the left wire passage 166, as shown in FIG. 11. The first position is located in the left wire passage 166. Thus, the loop RP of the wire W is formed. Then, the control unit 82 rotates the twisting motor 146 in the forward direction. As the sleeve unit 152 (see FIG. 14) moves forward, the left clamp 164 moves rightward toward the clamp shaft 160. The left wire passage 166 is thereby narrowed, and the leading end W1 of the wire W is finally held between the left clamp 164 and the clamp shaft 160. Thus, the leading end W1 of the wire W is held by the holding unit 156.

As shown in FIG. 11, to tie the rebars R with the wire W, the user firstly passes the rebars R through the loop RP of the wire W before pulling the trigger 70. The user then pulls the trigger 70 (see FIG. 2). In response, the control unit 82 executes the tying process in S30 of FIG. 22. Specifically, this tying process comprises the pullback process, the second holding process, the cutting process, the twisting process, the bending process, and the wire releasing process. Since the loop RP of the wire W is already formed and the leading end W1 of the wire W is already held by the holding unit 156, the tying process does not comprise the winding process nor the first holding process.

(Twelfth Embodiment) For a twelfth embodiment, differences from the first embodiment are described. In the twelfth embodiment, in the wire prior-feeding processes in S4 of FIGS. 19 and S38 of FIG. 22, the control unit 82 first rotates the feeding motor 88 in the forward direction by the second number of rotations. Thereby, as shown in FIG. 11, the leading end W1 of the wire W is moved to the left wire passage 166. The first position is located in the left wire passage 166. Thus, the loop RP of the wire W is formed.

To tie the rebars R with the wire W, the user firstly passes the rebars R through the loop RP of the wire W before pulling the trigger 70, without the leading end W1 of the wire W held by the holding unit 156. Then, the user pulls the trigger 70 (see FIG. 2). In response, the control unit 82 executes the tying process in S30 of FIG. 22. Specifically, this tying process comprises the first holding process, the pullback process, the second holding process, the cutting process, the twisting process, the bending process, and the wire releasing process. Since the loop RP of the wire W is already formed, the tying process does not comprise the winding process.

(Thirteenth Embodiment) For a thirteenth embodiment, differences from the second embodiment are described. As shown in FIG. 32, the holding unit 156 comprises a hook 500. The hook 500 extends forward from the front portion of the sleeve unit 152. The hook 500 is configured to open and close as the sleeve unit 152 moves in the front-rear direction. When the sleeve unit 152 moves forward, the hook 500 closes and holds the loop RP of the wire W. When the sleeve unit 152 moves rearward, the hook 500 opens and releases the loop RP of the wire W.

In the thirteenth embodiment, in the wire prior-feeding processes in S4 of FIGS. 19 and S38 of FIG. 22, the control unit 82 first rotates the feeding motor 88 in the forward direction by the second number of rotations. Thereby, as shown in FIG. 32, the leading end W1 of the wire W passes through the first wire passage 120, passes through the second wire passage 122, and then passes through the first wire passage 120 again. Thus, the loop RP of the wire W is formed. Then, the control unit 82 rotates the twisting motor 146 in the forward direction. When the sleeve unit 152 moves forward, the hook 500 closes, and the loop RP of the wire W is thereby held by the hook 500.

To tie the rebars R with the wire W, the user firstly passes the rebars R through the loop RP of the wire W before pulling the trigger 70. Then, the user pulls the trigger 70 (see FIG. 25). In response, the control unit 82 executes the tying process in S30 of FIG. 22. Specifically, this tying process comprises the cutting process, the twisting process, the bending process, and the wire releasing process. Since the loop RP of the wire W is already formed and held by the hook 500, the tying process does not comprise the winding process, the first holding process, the pullback process, nor the second holding process.

In the wire releasing process, the control unit 82 rotates the twisting motor 146 in the reverse direction. When the sleeve unit 152 moves rearward, the hook 500 opens. The loop RP of the wire W is thereby released from the hook 500. Since the cutting process, the twisting process, and the bending process have been already described in the first embodiment, descriptions for these processes are omitted here.

(Fourteenth Embodiment) In a fourteenth embodiment, differences from the thirteenth embodiment are described. In the fourteenth embodiment, in the wire prior-feeding processes in S4 of FIGS. 19 and S38 of FIG. 22, the control unit 82 rotates the feeding motor 88 in the forward direction by the second number of rotations. Thereby, as shown in FIG. 32, the leading end W1 of the wire W passes through the first wire passage 120, passes through the second wire passage 122, and then passes through the first wire passage 120 again. Thus, the loop RP of the wire W is formed.

To tie the rebars R with the wire W, the user firstly passes the rebars R through the loop RP of the wire W before pulling the trigger 70, without the loop RP of the wire W held by the hook 500. Then, the user pulls the trigger 70 (see FIG. 25). In response, the control unit 82 executes the tying process in S30 of FIG. 22. Specifically, this tying process comprises the holding process, the cutting process, the twisting process, the bending process, and the wire releasing process. Since the loop RP of the wire W is already formed, the tying process does not comprise the winding process.

In the holding process, the control unit 82 rotates the twisting motor 146 in the forward direction. As the sleeve unit 152 moves forward, the hook 500 closes. The loop RP of the wire W is thereby held by the hook 500.

(Variants) In an embodiment, the rebar tying machine 2 may be a machine configured to autonomously move on the rebars R.

In an embodiment, the first position may be located between the cutter 128 and the first wire passage 120.

In an embodiment, the bending member 192 may be fixed to the main body housing 4.

In an embodiment, the contact surface 194 may not be curved.

In an embodiment, the bending member 192 may not define the second wire passage 122.

In an embodiment, the bending member 192 may bend the terminal end W2 of the wire W toward the rebars R after the cutting process has been completed and before the twisting process is started.

In an embodiment, the link member 100 may support the first roller 96 such that the first roller 96 is rotatable. In this case, the first roller 96 corresponds to “second roller” and the second roller 98 corresponds to “first roller”.

In an embodiment, when the second roller 98 is in the second state, the teeth 98a of the second roller 98 may be engaged with the teeth 96a of the first roller 96. In this case, the distance between the first roller 96 and the second roller 98 is greater than the distance between the first roller 96 and the second roller 98 in the first state. Further, the wire W is held between the first roller 96 and the second roller 98. A force for holding the wire W between the first roller 96 and the second roller 98 in the second state is less than a force for holding the wire W between the first roller 96 and the second roller 98 in the first state.

In an embodiment, the reel holding section 22 may not define the reel housing space 36 therein. In this case, the reel 24 is partially exposed when the reel cover 6 is in the prohibited state.

In an embodiment, the actuation member 42 may comprise a contact portion that is not rotatable. In this case, the contact portion pushes the lower end of the link member 100.

In an embodiment, the lock lever 52 may be mounted in the reel holding section 22.

The rebar tying machines 2 according to the second to eighth embodiments and the eleventh to fourteenth embodiments may comprise the pushable member 400 described in connection with the ninth embodiment. In this case, the control unit 82 may execute the tying process in S30 of FIG. 22 in response to the pushable member 400 being pushed by the rebars R while the trigger 70 (see FIG. 2) is being pulled. The control unit 82 may execute the tying process in S30 of FIG. 22 in response to the pushable member 400 being pushed by the rebars R.

Claims

1. A rebar tying machine configured to tie rebars with a wire, comprising: a reel holding section configured to hold a reel including the wire such that the reel is rotatable about a reel rotation axis;a reel stopper configured to be switchable between a prohibited state in which the reel is prohibited from being removed from the reel holding section and a permitted state in which the reel is permitted to be removed from the reel holding section;a first roller configured to be rotatable;a second roller configured to be rotatable, wherein the second roller is configured to be switchable between a first state in which the wire is held between the first roller and the second roller and a second state in which a distance between the first roller and the second roller is longer than a distance between the first roller and the second roller in the first state; anda twisting unit configured to twist the wire wound around the rebars by the first roller and the second roller,whereinthe second roller is configured to switch from the first state to the second state when the reel stopper switches from the prohibited state to the permitted state.

2. The rebar tying machine according to claim 1, wherein the wire is not held between the first roller and the second roller when the second roller is in the second state.

3. The rebar tying machine according to claim 1, wherein the second roller switches from the second state to the first state when the reel stopper switches from the permitted state to the prohibited state.

4. The rebar tying machine according to claim 1, wherein the reel holding section has a reel housing space for housing the reel therein.

5. The rebar tying machine according to claim 1, further comprising a link member supporting the second roller such that the second roller is rotatable, wherein the link member is configured to switch the second roller between the first state and the second state, wherein the reel stopper comprises an actuation member configured to actuate the link member when the reel stopper switches from the prohibited state to the permitted state.

6. The rebar tying machine according to claim 5, further comprising a biasing member configured to bias the link member to switch the second roller from the second state to the first state.

7. The rebar tying machine according to claim 6, wherein the reel stopper is pivotable between a first position at which the reel stopper is positioned in the prohibited state and a second position at which the reel stopper is positioned in the permitted state, and the reel stopper is configured to pivot toward the first position when the reel stopper is positioned closer to the first position than a neutral position is, which is between the first position and the second position, and pivot toward the second position when the reel stopper is positioned closer to the second position than the neutral position is.

8. The rebar tying machine according to claim 5, wherein the actuation member comprises a roller configured to be rotatable and contact the link member.

9. The rebar tying machine according to claim 5, wherein the link member is pivotable about a link pivot axis, and a distance between the link pivot axis and a position of the link member actuated by the reel stopper is longer than a distance between the link pivot axis and a position where the link member supports the second roller.

10. The rebar tying machine according to claim 1, further comprising a lock lever mounted on the reel stopper and configured to be manipulated by a user, wherein the lock lever is configured to keep the reel stopper in the prohibited state when engaged with the reel holding section.

11. The rebar tying machine according to claim 1, wherein the reel stopper is pivotable about a stopper pivot axis, and the stopper pivot axis is located above the reel rotation axis and below the second roller.

12. The rebar tying machine according to claim 1, further comprising: a reel pressing member mounted on the reel stopper; anda biasing member configured to bias the reel pressing member toward the reel when the reel stopper is in the prohibited state.

13. A rebar tying machine configured to tie rebars with a wire, comprising: a reel holding section configured to hold a reel including the wire such that the reel is rotatable about a reel rotation axis;a reel stopper configured to be switchable between a prohibited state in which the reel is prohibited from being removed from the reel holding section and a permitted state in which the reel is permitted to be removed from the reel holding section;a first roller configured to be rotatable;a second roller configured to be rotatable, wherein the second roller is configured to be switchable between a first state in which the wire is held between the first roller and the second roller and a second state in which a force for holding the wire between the first roller and the second roller is smaller than a force for holding the wire between the first roller and the second roller in the first state; anda twisting unit configured to twist the wire wound around the rebars by the first roller and the second roller,whereinthe second roller switches from the first state to the second state when the reel stopper switches from the prohibited state to the permitted state.

14. A rebar tying machine configured to tie rebars with a wire, comprising: a reel holding section configured to hold a reel including the wire such that the reel is rotatable about a reel rotation axis;a reel stopper configured to be switchable between a prohibited state in which the reel is prohibited from being removed from the reel holding section and a permitted state in which the reel is permitted to be removed from the reel holding section; anda lock lever configured to keep the reel stopper in the prohibited state when engaged with the reel holding section,whereinthe lock lever is configured to engage with the reel holding section without being manipulated by a user after the reel stopper has switched from the permitted state to the prohibited state.

15. The rebar tying machine according to claim 2, wherein the second roller switches from the second state to the first state when the reel stopper switches from the permitted state to the prohibited state, the reel holding section has a reel housing space for housing the reel therein,the rebar tying machine further comprises a link member supporting the second roller such that the second roller is rotatable,the link member is configured to switch the second roller between the first state and the second state,the reel stopper comprises an actuation member configured to actuate the link member when the reel stopper switches from the prohibited state to the permitted state,the rebar tying machine further comprises a first biasing member configured to bias the link member to switch the second roller from the second state to the first state,the reel stopper is pivotable between a first position at which the reel stopper is positioned in the prohibited state and a second position at which the reel stopper is positioned in the permitted state,the reel stopper is configured to pivot toward the first position when the reel stopper is positioned closer to the first position than a neutral position is, which is between the first position and the second position, and pivot toward the second position when the reel stopper is positioned closer to the second position than the neutral position is,the actuation member comprises a roller configured to be rotatable and contact the link member,the link member is pivotable about a link pivot axis,a distance between the link pivot axis and a position of the link member actuated by the reel stopper is longer than a distance between the link pivot axis and a position where the link member supports the second roller,the rebar tying machine further comprises a lock lever mounted on the reel stopper and configured to be manipulated by a user,the lock lever is configured to keep the reel stopper in the prohibited state when engaged with the reel holding section,the reel stopper is pivotable about a stopper pivot axis,the stopper pivot axis is located above the reel rotation axis and below the second roller, andthe rebar tying machine further comprises:a reel pressing member mounted on the reel stopper; anda second biasing member configured to bias the reel pressing member toward the reel when the reel stopper is in the prohibited state.