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.

What is claimed is: 
     
         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; and   a twisting unit configured to twist the wire wound around the rebars by the first roller and the second roller,   wherein   the 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; and   a 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; and   a twisting unit configured to twist the wire wound around the rebars by the first roller and the second roller,   wherein   the 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; and   a lock lever configured to keep the reel stopper in the prohibited state when engaged with the reel holding section,   wherein   the 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, and   the rebar tying machine further comprises:   a reel pressing member mounted on the reel stopper; and   a second biasing member configured to bias the reel pressing member toward the reel when the reel stopper is in the prohibited state.