Rebar tying machine

Abstract

To provide a technology capable of enhancing the degree of layout freedom of an operation unit.SOLUTION: A reinforcement binding machine is provided with: a rotatable screw shaft; a sleeve movable in a longitudinal direction and rotatable, into which the screw shaft is inserted; fin members attached on the sleeve to allow / restrict rotation of the sleeve; a push member attached on the sleeve rotatably around the sleeve, which does not rotate even when the sleeve rotates; an operation unit has a longer direction in a longitudinal direction and is operated with the push member when the sleeve moves in the longitudinal direction; and a clamping unit projecting from a front part of the sleeve and rotatable together with the sleeve to clamp the wire. The push member is arranged forward of the fin members.SELECTED DRAWING: Figure 9

Description

[Technical Field]

[0001] The present specification relates to a reinforcing bar binding machine. [Background Art]

[0002] Patent Document 1 discloses a reinforcing bar binding machine. The reinforcing bar binding machine binds reinforcing bars using a wire. The reinforcing bar binding machine comprises: a rotatable screw shaft; a sleeve into which the screw shaft is inserted, the sleeve being movable in the front-rear direction and rotatable; a fin member attached to the sleeve, the fin member permitting and inhibiting rotation of the sleeve; a push member rotatably attached to the sleeve around the sleeve, the push member not rotating even when the sleeve rotates; an operated unit extending in the front-rear direction and operated by the push member when the sleeve moves in the front-rear direction; and a gripping unit protruding from a front portion of the sleeve, the gripping unit being rotatable together with the sleeve and gripping a wire. The push member is disposed rearward of the fin member. [Prior Art Literature] [Patent Literature]

[0003] [Patent Document 1] Japanese Unexamined Patent Publication No. 2009-275486 [Summary of the Invention] [Problem to be Solved by the Invention]

[0004] In conventional reinforcing bar binding machines such as that described above, the operated unit is often disposed forward of the push member. Since the operated unit operates when actuated by the push member, it is necessary to design the space required for disposing the operated unit in consideration of the positions of the operated unit before and after operation. It is desired to reduce the space required for disposing the operated unit and increase the degree of freedom in arrangement of the operated unit. The present specification discloses a technique capable of increasing the degree of freedom in arrangement of the operated unit. [Means for Solving the Problem]

[0005] The rebar tying machine disclosed herein ties reinforcing bars using wire. The rebar tying machine comprises a rotatable screw shaft, a sleeve into which the screw shaft is inserted and which is movable and rotatable in the front-rear direction, a fin member attached to the sleeve which allows and prohibits the rotation of the sleeve, a push member attached to the sleeve which is rotatable around the sleeve and which does not rotate even when the sleeve rotates, an operated unit which has a longitudinal direction in the front-rear direction and is operated by the push member when the sleeve moves in the front-rear direction, and a gripping unit which protrudes from the front of the sleeve, is rotatable with the sleeve and grips the wire. The push member is positioned in front of the fin member.

[0006] According to the above configuration, the push member is positioned in front of the fin member, Compared to a configuration where the push member is positioned behind the fin member, the space required for positioning the operated unit can be reduced in the front-to-back direction. This increases the degree of freedom in positioning the operated unit. [Brief explanation of the drawing]

[0007] [Figure 1] This is a perspective view of the rebar tying machine 2 of the first embodiment. [Figure 2] This is a left side view of the rebar tying machine 2 of the first embodiment, with the left housing 8 and reel cover 10 removed. [Figure 3] This is a perspective view of the rebar tying machine 2 of the first embodiment with the reel cover 10 in the open position. [Figure 4] This is a cross-sectional view of the rebar tying machine 2 of the first embodiment, near the guide unit 42. [Figure 5] This is a cross-sectional view of the cutting unit 44 and the twisting unit 46 of the first embodiment. [Figure 6]This is a left side view of the vicinity of the twisting unit housing 14 in the rebar tying machine 2 of the first embodiment, with the left housing 8 removed. [Figure 7] This is a cross-sectional view of the cutting unit 44 and the twisting unit 46 of the first embodiment. [Figure 8] This is a perspective view of the torsion unit 46 of the first embodiment. [Figure 9] This is a cross-sectional view of the torsion unit 46 of the first embodiment. [Figure 10] This is a perspective view of the rotation limiting unit 48 of the first embodiment. [Figure 11] This is a cross-sectional view of the torsion unit 46 and sensor unit 150 of the first embodiment. [Figure 12] This is a perspective view of the torsion unit 46 of the first embodiment, near the gripping unit 100. [Figure 13] This is a perspective view of the right-side clamp member 154 of the first embodiment. [Figure 14] This is a perspective view of the left clamp member 156 of the first embodiment. [Figure 15] This is a cross-sectional view of the left clamp member 156 of the first embodiment, near the wire tip guide surface 190. [Figure 16] This is a side view of the wire W and reinforcing bar R after the wire W has been twisted in the first embodiment. [Figure 17] This is a cross-sectional view of the left clamp member 156 of the second embodiment, near the wire tip guide surface 190. [Figure 18] This is an enlarged cross-sectional view of the wire tip guide surface 190 of the second embodiment when it is in contact with the tip of the wire W. [Figure 19] This is a cross-sectional view of the first cutter 70 and the second cutter 72 of the second embodiment. [Figure 20] This is an enlarged cross-sectional view of the wire tip guide surface 190 of the second embodiment when it is in contact with the wire tip surface 300. [Figure 21] This is a cross-sectional view of the first cutter 70 and the second cutter 72 of the third embodiment. [Modes for carrying out the invention]

[0008] Hereinafter, representative non-limiting specific examples of the present invention will be described in detail with reference to the drawings. This detailed description is merely intended to provide those skilled in the art with details for carrying out preferred examples of the present invention, and is not intended to limit the scope of the present invention. Additionally, additional features and inventions disclosed below may be used separately or in combination with other features and inventions to provide further improved rebar binding machines, methods for manufacturing the same, and methods for using the same.

[0009] Furthermore, combinations of features and steps disclosed in the following detailed description are not essential for practicing the present invention in the broadest sense, and are described solely for the purpose of illustrating representative specific examples of the present invention. Furthermore, various features of the representative specific examples described above and below, as well as various features set forth in the independent and dependent claims, are not required to be combined in the order set forth or listed herein to provide additional and useful embodiments of the present invention.

[0010] All features described in this specification and / or the claims are intended to be disclosed separately and independently of each other, apart from the constitution of features described in the examples and / or claims, as limitations on the original disclosure of the application and the specific claimed subject matter. Furthermore, all descriptions of numerical ranges and groups or populations are intended to disclose intermediate configurations thereof as limitations on the original disclosure of the application and the specific claimed subject matter.

[0011] In one or more embodiments, the operated unit may comprise: an operated member that can be abutted by a push member and is operated by the push member when abutted; and a cutter capable of cutting a wire and actuated when the operated member is operated by the push member.

[0012] The cutter needs to be positioned near the wire in order to cut it. With the above configuration, the push member is positioned in front of the fin member, so the distance between the push member and the reinforcing bar can be shortened compared to a configuration in which the push member is positioned behind the fin member. This makes the operated unit smaller in the front-to-back direction.

[0013] In one or more embodiments, the operated unit may further include a link member connecting the operated member and the cutter.

[0014] With the above configuration, the link member can be made smaller in the front-to-back direction compared to a configuration in which the push member is positioned behind the fin member.

[0015] In one or more embodiments, the push member may be sandwiched between the sleeve and the fin member in the front-rear direction.

[0016] With the above configuration, the push member can be attached to the sleeve with a simple structure.

[0017] In one or more embodiments, the rebar tying machine may further include a trigger that is pressed by a user. The trigger may be aligned with the operated unit in the front-to-back direction when the rebar tying machine is viewed in a direction perpendicular to the front-to-back direction.

[0018] With the above configuration, compared to a configuration where the trigger is not aligned with the operated unit in the front-to-back direction when the rebar tying machine is viewed in a direction perpendicular to the front-to-back direction, it is possible to suppress the increase in size of the rebar tying machine in the direction perpendicular to the front-to-back direction.

[0019] (First embodiment) As shown in Figure 1, the rebar tying machine 2 ties multiple reinforcing bars R together using wire W. The rebar tying machine 2 uses wire W of various diameters (for example, from 0.5 mm to 2.5 mm in diameter) depending on the diameter of the reinforcing bars R used. For example, when tying small-diameter reinforcing bars R with a diameter of 16 mm or less (for example, 16 mm in diameter), wire W with a diameter of 1.6 mm or less (for example, 0.8 mm) is used, and when tying large-diameter reinforcing bars R with a diameter greater than 16 mm (for example, 25 mm or 32 mm in diameter), wire W with a diameter of 1.6 mm or more (for example, 2.0 mm) is used. Hereinafter, the longitudinal direction of the twisting unit 46 (see Figure 8) will be referred to as the front-to-back direction, the direction perpendicular to the front-to-back direction will be referred to as the up-and-down direction, and the direction perpendicular to both the front-to-back direction and the up-and-down direction will be referred to as the left-to-right direction.

[0020] The rebar tying machine 2 comprises a main body 4 and a battery pack BP. The main body 4 comprises a right-side housing 6 that defines the external shape of the right half of the main body 4, a left-side housing 8 that defines the external shape of the left half of the main body 4, and a reel cover 10 that is rotatably attached to the front lower part of the left-side housing 8.

[0021] The main body 4 comprises a twisting unit housing 14, a grip portion 16, a battery mounting portion 18, a feed unit housing 20, and a reel housing 22. The twisting unit housing 14, the grip portion 16, the battery mounting portion 18, and the feed unit housing 20 are formed by a right housing 6 and a left housing 8. The reel housing 22 is formed by a right housing 6, a left housing 8, and a reel cover 10.

[0022] As shown in Figure 2, the torsion unit housing 14 extends in the front-rear direction. The grip portion 16 is located at the lower rear of the torsion unit housing 14. The grip portion 16 is held by the user. The longitudinal direction of the grip portion 16 is slightly inclined with respect to the vertical direction. A trigger 24 is attached to the upper front of the grip portion 16.

[0023] The battery mounting section 18 is located at the lower end of the grip section 16. The battery pack BP is detachably attached to the lower end of the battery mounting section 18. The battery pack BP is attached to the battery mounting section 18 by sliding it forward and downward relative to the battery mounting section 18, and removed from the battery mounting section 18 by sliding it rearward and upward relative to the battery mounting section 18. The sliding direction of the battery pack BP is inclined with respect to the front-to-back direction. The battery pack BP is equipped with a secondary battery, such as a lithium-ion battery.

[0024] The feed unit housing 20 is located at the front lower part of the twist unit housing 14. The feed unit housing 20 is located in front of the grip portion 16.

[0025] The reel housing 22 is located at the lower end of the feed unit housing 20. In Figure 2, the reel housing 22 is shown by a dashed line. As shown in Figure 3, the reel housing 22 is capable of housing a reel 28. The reel 28 comprises a wire W and a bobbin 32 on which the wire W is wound. The reel 28 is rotatably supported in the reel housing 22. The reel 28 is detachable from the reel housing 22 when the reel cover 10 is open relative to the left housing 8.

[0026] As shown in Figure 2, the rebar tying machine 2 includes a control unit 38, a feeding unit 40, a guide unit 42, a cutting unit 44, a twisting unit 46, and a rotation limiting unit 48 (see Figure 10).

[0027] The control unit 38 is housed in the battery mounting section 18. When the trigger 24 is pressed by the user, the control unit 38 performs a binding operation to tie the reinforcing bars R using the wire W.

[0028] The feed unit 40 is housed in the feed unit housing 20. The feed unit 40 comprises a feed motor 50 and a feed roller unit 52. The feed motor 50 is, for example, a brushless motor. The feed motor 50 rotates using power supplied from the battery pack BP. When the feed motor 50 rotates, the feed roller unit 52 operates. By rotating, the feed roller unit 52 pulls the wire W out of the bobbin 32 and feeds it forward and upward toward the reinforcing bar R. The feed roller unit 52 also rotates to pull the wire W back toward the bobbin 32.

[0029] The guide unit 42 is fixed to the front end of the twist unit housing 14. The guide unit 42 comprises an upper curl guide 56 and a lower curl guide 58. As shown in Figure 4, the upper curl guide 56 is open to the bottom. The upper curl guide 56 has an upper wire passage 60 which has an upwardly convex curved shape. The lower curl guide 58 is located below the upper curl guide 56. The lower curl guide 58 is open to the top. The lower curl guide 58 has a lower wire passage 62.

[0030] The wire W, fed by the feed unit 40 (see Figure 2), is sent to the upper wire passage 60. As the wire W passes through the upper wire passage 60 from rear to front, the wire W is given a downward curl by the upper curl guide 56. After passing through the upper wire passage 60, the wire W is sent to the lower wire passage 62. After passing through the lower wire passage 62 from front to rear, the wire W is sent towards the rear upper side. Guided by the upper curl guide 56 and the lower curl guide 58, the wire W is wound around the reinforcing bar R. Hereinafter, the trajectory in which the tip of the wire W moves as it is guided by the upper curl guide 56 and the lower curl guide 58 may be referred to as the winding trajectory WO.

[0031] As shown in Figure 2, the cutting unit 44 is housed in the twisting unit housing 14. As shown in Figure 5, the cutting unit 44 comprises a base member 66, a guide member 68 (see Figure 4), a first cutter 70, a second cutter 72, a first lever member 74, a second lever member 76, and a link member 78.

[0032] The guide member 68 shown in Figure 4 is fixed to the base member 66. The guide member 68 has a guide hole 68a. The width of the guide hole 68a in the front-to-back direction and the width in the left-to-right direction gradually narrow from the bottom to the top before becoming constant. The wire W fed by the feed unit 40 (see Figure 2) passes through the guide hole 68a.

[0033] As shown in Figure 5, the first cutter 70 is fixed to the base member 66. The first cutter 70 has a first cutting opening 80. The first cutter 70 is inserted into the second cutter 72. The second cutter 72 is supported by the first cutter 70 so as to be rotatable around the first cutter 70. The second cutter 72 has a second cutting opening 82.

[0034] As shown in Figure 4, the guide hole 68a, the first cutting opening 80, and the second cutting opening 82 are located on the passage through which the wire W is fed from the feed unit 40 toward the upper curl guide 56. Before the cutting unit 44 cuts the wire W, the first cutting opening 80 and the second cutting opening 82 are in communication. As the wire W is fed from the feed unit 40 toward the upper curl guide 56, it is guided by the guide hole 68a and passes through the first cutting opening 80 and the second cutting opening 82. When the second cutter 72 rotates in the first direction D1 relative to the first cutter 70 while the wire W is passing through the first cutting opening 80 and the second cutting opening 82, the first cutter 70 and the second cutter 72 come into contact with the wire W and cut the wire W.

[0035] As shown in Figure 5, the first lever member 74 and the second lever member 76 are fixed to each other via the first shaft 86 and the second shaft 88. The first lever member 74 and the second lever member 76 are rotatable around the first shaft 86. The first shaft 86 is fixed to the left housing 8 (see Figure 1). The second shaft 88 is not fixed to the left housing 8. When the first lever member 74 and the second lever member 76 rotate around the first shaft 86, the second shaft 88 moves together with the first lever member 74 and the second lever member 76. The first lever member 74 has a first projection 90 which is operated by the torsion unit 46. The first projection 90 is located at the upper end of the first lever member 74. The second lever member 76 has a second projection 92 which is operated by the torsion unit 46. The second projection 92 is located at the upper end of the second lever member 76. The second projection 92 is positioned in front of the first projection 90.

[0036] The rear end of the link member 78 is attached to the second shaft 88. The front end of the link member 78 is attached to the second cutter 72. The link member 78 connects the second shaft 88 and the second cutter 72. The link member 78 has an elongated shape. As shown in Figure 6, when the rebar tying machine 2 is viewed from the rear to the front, the link member 78 overlaps with the trigger 24 in the front-rear direction. Also, when the rebar tying machine 2 is viewed from the left to the right, the link member 78 is aligned with the trigger 24 in the front-rear direction. The link member 78 is located near the upper end of the grip portion 16 in the vertical direction. The upper end of the trigger 24 is located above the lower end of the link member 78.

[0037] As shown in Figure 5, before the cutting unit 44 cuts the wire W, the second shaft 88 is positioned in front of the first shaft 86. As shown in Figure 7, when the second projection 92 is operated forward, the second shaft 88 moves backward, and the link member 78 also moves backward. As a result, the second cutter 72 rotates in the first direction D1, and the wire W is sandwiched between the first cutter 70 and the second cutter 72 and cut. Also, as shown in Figure 5, when the first projection 90 is operated backward after the wire W has been cut, the second shaft 88 moves forward, and the link member 78 also moves forward. As a result, the second cutter 72 rotates in the second direction D2, opposite to the first direction D1. As a result, the second cutter 72 returns to its initial state where the first cutting opening 80 and the second cutting opening 82 are in communication.

[0038] As shown in Figure 6, the torsion unit 46 is housed in the torsion unit housing 14. The torsion unit 46 comprises a torsion motor 96, a sleeve unit 98, and a gripping unit 100. The torsion motor 96 is located above the grip portion 16. The torsion motor 96 is, for example, a brushless motor. The torsion motor 96 rotates using power supplied from the battery pack BP. The rotation of the torsion motor 96 is transmitted to the sleeve unit 98.

[0039] As shown in Figure 8, the sleeve unit 98 includes a screw shaft 102, an inner sleeve 104 (see Figure 9), an outer sleeve 106, a fin member 108, and a push member 110.

[0040] As shown in Figure 9, the screw shaft 102 extends along a central axis CX that extends in the front-rear direction. The screw shaft 102 rotates around the central axis CX as the torsion motor 96 rotates. A ball groove 114 is formed on the outer surface of the screw shaft 102. The ball groove 114 extends spirally in the front-rear direction. A ball 116 is movably held in the ball groove 114.

[0041] The inner sleeve 104 comprises a cylindrical portion 118 and a flange portion 120. The cylindrical portion 118 extends along the central axis CX. A screw shaft 102 is inserted into the cylindrical portion 118. The cylindrical portion 118 has a ball-holding hole 122 that penetrates the cylindrical portion 118 in the thickness direction. The ball-holding hole 122 rotatably holds the ball 116 in the ball groove 114. The flange portion 120 protrudes radially outward from the rear end of the cylindrical portion 118.

[0042] The outer sleeve 106 comprises a cylindrical portion 124 and a flange portion 126. The cylindrical portion 124 extends along the central axis CX. The cylindrical portion 118 of the inner sleeve 104 is inserted into the cylindrical portion 124. The cylindrical portion 124 is fixed to the cylindrical portion 118 by a set screw 128. As a result, the outer sleeve 106 moves and rotates in the front-rear direction together with the inner sleeve 104. The rear end of the cylindrical portion 124 abuts against the flange portion 120 from the front. The cylindrical portion 124 contacts the ball 116, thereby preventing the ball 116 from coming out of the ball groove 114 and the ball holding hole 122. The flange portion 126 protrudes radially outward from the outer circumferential surface of the cylindrical portion 124. The flange portion 126 is positioned in front of the rear end of the cylindrical portion 124.

[0043] An outer sleeve 106 is inserted into the fin member 108. The fin member 108 is attached to the outer sleeve 106. The fin member 108 comprises a base portion 130 and eight fin portions 132. The base portion 130 has a substantially cylindrical shape. The base portion 130 abuts against the flange portion 120 of the inner sleeve 104 from the front. The fin portions 132 protrude radially outward from the outer circumferential surface of the base portion 130. As shown in Figure 8, the eight fin portions 132 are arranged around the outer circumferential surface of the base portion 130 at 45-degree intervals from each other.

[0044] The fin portion 132 works in cooperation with the rotation limiting unit 48 shown in Figure 10 to allow and prohibit the rotation of the outer sleeve 106. The configuration of the rotation limiting unit 48 will be described first. As shown in Figure 10, the rotation limiting unit 48 comprises a base member 136, a lower stopper 138, an upper stopper 140, a lower torsion spring 142, and an upper torsion spring 144. The lower stopper 138 is pivotably supported at the lower part of the base member 136 via a lower oscillating shaft 146. The lower stopper 138 includes a restricting piece 138a. The restricting piece 138a is located at the upper part of the lower stopper 138. The lower torsion spring 142 biases the restricting piece 138a in the direction of opening it outward (i.e., in the direction of moving the restricting piece 138a away from the base member 136). The upper stopper 140 is pivotably supported on the upper part of the base member 136 via an upper swing shaft 148. The upper stopper 140 includes a restricting piece 140a, which is located below the upper stopper 140. The front end of the restricting piece 140a is positioned in front of the front end of the restricting piece 138a, and the rear end of the restricting piece 140a is positioned in front of the rear end of the restricting piece 138a. The upper torsion spring 144 biases the restricting piece 140a in an outward direction (i.e., in a direction away from the base member 136).

[0045] Regarding the lower stopper 138, when the screw shaft 102 rotates clockwise in direction D3 (see Figure 8) when viewed from the rear around the central axis CX, the rotation of the outer sleeve 106 is prohibited when the fin portion 132 contacts the restricting piece 138a from above. At this time, the inner sleeve 104, outer sleeve 106, and fin member 108 move forward as the ball 116 (see Figure 9) moves within the ball groove 114 (see Figure 9) in conjunction with the rotation of the screw shaft 102. On the other hand, when the screw shaft 102 rotates counterclockwise in direction D4 (see Figure 8) when viewed from the rear around the central axis CX, the fin portion 132 pushes the restricting piece 138a inward even when it contacts it. At this time, the rotation of the outer sleeve 106 is not prohibited, and the inner sleeve 104, outer sleeve 106, and fin member 108 rotate together with the screw shaft 102 in a counterclockwise direction D4 around the central axis CX.

[0046] Regarding the upper stopper 140, when the screw shaft 102 rotates clockwise in direction D3 (see Figure 8) when viewed from the rear around the central axis CX, the fin portion 132 pushes the restricting piece 140a inward even when it comes into contact with it. In this case, the rotation of the outer sleeve 106 is not prohibited, and the inner sleeve 104, outer sleeve 106, and fin member 108 rotate together with the screw shaft 102 clockwise in direction D3 around the central axis CX. On the other hand, when the screw shaft 102 rotates counterclockwise in direction D4 (see Figure 8) when viewed from the rear around the central axis CX, the rotation of the outer sleeve 106 is prohibited when the fin portion 132 comes into contact with the restricting piece 140a from below. At this time, the inner sleeve 104, outer sleeve 106, and fin member 108 move backward as the screw shaft 102 rotates, causing the ball 116 (see Figure 9) to move within the ball groove 114 (see Figure 9).

[0047] Returning to Figure 9, the push member 110 will be described. The push member 110 has a substantially plate shape. The cylindrical portion 124 of the outer sleeve 106 is inserted into the push member 110. The push member 110 is attached to the cylindrical portion 124. The push member 110 is rotatable around the outer circumferential surface of the cylindrical portion 124. The push member 110 is sandwiched between the rear end of the flange portion 126 and the front end of the base portion 130 of the fin member 108. The push member 110 is positioned in front of the fin member 108 (i.e., on the reinforcing bar R side). The push member 110 moves in the front-rear direction together with the outer sleeve 106. Furthermore, the rotation of the push member 110 relative to the right housing 6 (see Figure 1) and the left housing 8 (see Figure 1) is restricted. The push member 110 does not rotate around the central axis CX even when the outer sleeve 106 rotates.

[0048] As shown in Figure 7, when the push member 110 moves forward together with the outer sleeve 106, it comes into contact with the second projection 92 of the second lever member 76, pushing the second projection 92 forward. This causes the second cutter 72 to rotate in the first direction D1. Also, as shown in Figure 5, when the push member 110 moves backward together with the outer sleeve 106, it comes into contact with the first projection 90 of the first lever member 74, pushing the first projection 90 backward. This causes the second cutter 72 to rotate in the second direction D2.

[0049] As shown in Figure 11, the push member 110 is equipped with a permanent magnet 110a. The permanent magnet 110a is located at the lower end of the push member 110. A sensor unit 150 is positioned opposite the permanent magnet 110a in the vertical direction. The sensor unit 150 comprises a sensor substrate 150a and two magnetic sensors 150b and 150c. The magnetic sensors 150b and 150c are fixed on the sensor substrate 150a. Magnetic sensor 150b is positioned opposite the permanent magnet 110a when the gripping unit 100 is in its initial state. Magnetic sensor 150c is positioned in front of magnetic sensor 150b. Magnetic sensor 150c is positioned opposite the permanent magnet 110a when the wire W is clamped between the left-side clamp member 156 and the clamp shaft 152, which will be described later. When the magnetic sensors 150b and 150c are facing the permanent magnet 110a, they detect the magnetism from the permanent magnet 110a. As a result, the sensor unit 150 detects the front-rear position of the push member 110 (i.e., the front-rear position of the outer sleeve 106).

[0050] As shown in Figure 12, the gripping unit 100 protrudes forward (towards the reinforcing bar R) from the front of the sleeve unit 98. The gripping unit 100 extends along the central axis CX. The gripping unit 100 comprises a clamp shaft 152, a right-side clamp member 154, and a left-side clamp member 156.

[0051] As shown in Figure 9, the clamp shaft 152 is inserted into the inner sleeve 104 and outer sleeve 106 from the front. The clamp shaft 152 is positioned on the central axis CX. The rear end of the clamp shaft 152 is attached to the front end of the screw shaft 102 via a mounting piece 157 (see Figure 7). The clamp shaft 152 cannot move in the front-rear direction relative to the screw shaft 102 due to the mounting piece 157. The clamp shaft 152 is rotatable around the screw shaft 102.

[0052] As shown in Figure 12, the clamp shaft 152 comprises a flat plate portion 158, a fitting hole 160, and an opening 162. The flat plate portion 158 is located at the front of the clamp shaft 152. The flat plate portion 158 has a substantially flat shape along the vertical and front-to-back directions. The fitting hole 160 penetrates the flat plate portion 158 in the thickness direction (left-to-right direction in Figure 12). The fitting hole 160 engages with the pin 164. The opening 162 is located behind the flat plate portion 158. The opening 162 penetrates the clamp shaft 152 in the left-to-right direction and extends in the front-to-back direction.

[0053] The right-side clamp member 154 is attached to the clamp shaft 152 so as to pass through the opening 162 of the clamp shaft 152 from right to left. The left-side clamp member 156 is attached to the clamp shaft 152 so as to pass through the opening 162 from left to right.

[0054] As shown in Figure 13, the right-side clamp member 154 comprises a base portion 166, a pin holding portion 168, a lower projection portion 170, a contact portion 172, a rear guard portion 174, and a front guard portion 176. The base portion 166 has a substantially flat plate shape that is aligned with the front-rear and left-right directions. Cam holes 166a and 166b are formed in the base portion 166. The cam holes 166a and 166b extend forward from the rear end, then bend and extend to the right front, then bend and extend forward again, then bend and extend to the right front, and then bend and extend forward again. The pin holding portion 168 is located near the right front end of the base portion 166. The pin holding portion 168 is located on the upper surface of the base portion 166. The pin holding portion 168 slidably holds the pin 164 (see Figure 12). The lower projection 170 protrudes downward from the right front end of the base portion 166. The contact portion 172 protrudes downward to the left from the lower end of the lower projection 170. The rear guard portion 174 protrudes to the left from the rear end of the contact portion 172. The front guard portion 176 protrudes to the left from the front end of the contact portion 172.

[0055] As shown in Figure 14, the left clamp member 156 comprises a base portion 178, an upper projection 180, a contact portion 182, an upper guard portion 184, and a front guard portion 186. The base portion 178 has a substantially flat plate shape along the front-rear and left-right directions. Cam holes 178a and 178b are formed in the base portion 178. The cam holes 178a and 178b extend forward from the rear end, then bend and extend to the left front, and then bend again and extend forward. The upper projection 180 protrudes upward from the left front end of the base portion 178. The contact portion 182 protrudes upward to the right from the upper end of the upper projection 180. The upper guard portion 184 protrudes to the right from the upper end of the contact portion 182. The front guard portion 186 protrudes to the right from the front end of the upper projection 180 and the front end of the contact portion 182. The front guard portion 186 is connected to the front end of the upper guard portion 184.

[0056] As shown in Figure 15, the upper guard portion 184 is provided with a wire tip guide surface 190. The wire tip guide surface 190 corresponds to the lower surface of the upper guard portion 184. The wire tip guide surface 190 has a planar shape. The wire tip guide surface 190 extends from the rear end toward the front and upward. The wire tip guide surface 190 is inclined with respect to the central axis CX so that it moves away from the central axis CX as it moves from the rear end toward the front end. That is, the distance between the wire tip guide surface 190 and the central axis CX is minimum at the rear end of the wire tip guide surface 190, increases as it moves from the rear end toward the front end of the wire tip guide surface 190, and is maximum at the front end of the wire tip guide surface 190.

[0057] The wire tip guide surface 190 is inclined with respect to a first virtual surface 192 that runs along the front-to-back and left-to-right directions. The inclination angle A1 of the wire tip guide surface 190 with respect to the first virtual surface 192 is greater than 0 degrees. The inclination angle A1 is the angle between the wire tip guide surface 190 and the first virtual surface 192, measured clockwise from the wire tip guide surface 190 when viewing the rebar tying machine 2 from right to left. The inclination angle A1 may also be 5 degrees or more. In this embodiment, the inclination angle A1 is 10 degrees. The wire tip guide surface 190 is inclined with respect to a second virtual surface 194 that runs along the left-to-right and up-to-down directions. The inclination angle A2 of the wire tip guide surface 190 with respect to the second virtual surface 194 is greater than 90 degrees. The inclination angle A2 is the angle between the wire tip guide surface 190 and the second virtual surface 194, measured clockwise from the wire tip guide surface 190 when viewing the rebar tying machine 2 from right to left. Furthermore, the inclination angle A2 may be 95 degrees or greater. In this embodiment, the inclination angle A2 is 100 degrees.

[0058] The wire tip guide surface 190 is positioned on the winding trajectory WO of the wire tip when the wire W is guided around the reinforcing bar R by the guide unit 42 (see Figure 4). The angle A3 between the wire tip guide surface 190 and the winding trajectory WO is greater than 90 degrees. Angle A3 is the angle between the wire tip guide surface 190 and the winding trajectory WO, measured clockwise from the wire tip guide surface 190 when viewing the reinforcing bar tying machine 2 from right to left. Angle A3 may also be 95 degrees or greater. In this embodiment, angle A3 is 100 degrees. Angle A3 is approximately the same as the inclination angle A2.

[0059] The front guard portion 186 is provided with a guard surface 196. The guard surface 196 corresponds to the rear surface of the front guard portion 186. The guard surface 196 is positioned in front of the wire tip guide surface 190 (towards the reinforcing bar R). The guard surface 196 is positioned between the wire tip guide surface 190 and the reinforcing bar R in the front-rear direction. The guard surface 196 has a flat plate shape. When the left clamp member 156 is viewed from the front to the rear, the guard surface 196 overlaps with the wire tip guide surface 190. The guard surface 196 is substantially parallel to the second virtual surface 194 and substantially perpendicular to the first virtual surface 192.

[0060] As shown in Figure 12, the base portion 166 of the right clamp member 154 and the base portion 178 of the left clamp member 156 are inserted into the opening 162 of the clamp shaft 152. In this state, the engagement pin 200 is positioned in the cam holes 166a and 178a (see Figure 14). Also, as shown in Figure 8, the engagement pin 202 is positioned in the cam holes 166b (see Figure 13) and 178b. The engagement pins 200 and 202 are held by the outer sleeve 106. When the outer sleeve 106 moves in the front-rear direction relative to the clamp shaft 152, the engagement pin 200 moves in the front-rear direction within the cam holes 166a and 178a, and the engagement pin 202 moves in the front-rear direction within the cam holes 166b and 178b.

[0061] As shown in Figure 12, in the initial state where the clamp shaft 152 protrudes forward from the outer sleeve 106, the right-side clamp member 154 is positioned furthest to the right of the clamp shaft 152. In this state, a right-side wire passage 204 through which the wire W can pass is formed between the lower projection 170 of the right-side clamp member 154 and the flat plate portion 158 of the clamp shaft 152. When the outer sleeve 106 moves forward relative to the clamp shaft 152 from this state, the right-side clamp member 154 moves to the left relative to the clamp shaft 152, then its leftward movement pauses, and then it moves to the left again. As a result, the wire W is clamped between the contact portion 172 and the flat plate portion 158 of the right-side clamp member 154, and the front end of the right-side wire passage 204 is covered by the front guard portion 176.

[0062] Furthermore, in the initial state where the clamp shaft 152 protrudes forward from the outer sleeve 106, the left clamp member 156 is positioned furthest to the left of the clamp shaft 152. In this state, a left wire passage 206 through which the wire W can pass is formed between the upper protrusion 180 of the left clamp member 156 and the flat plate portion 158 of the clamp shaft 152. When the outer sleeve 106 moves forward relative to the clamp shaft 152 from this state, the left clamp member 156 moves to the right relative to the clamp shaft 152. As a result, the wire W is clamped between the contact portion 182 and the flat plate portion 158 of the left clamp member 156, and the front end of the left wire passage 206 is covered by the front guard portion 186.

[0063] The behavior of the tip of the wire W fed by the feed unit 40 as it wraps around the reinforcing bar R will be explained. As shown in Figure 4, the tip of the wire W fed by the feed unit 40 (see Figure 2) is first guided by the guide hole 68a and passes through the first cutting opening 80 and the second cutting opening 82. Next, the tip of the wire W passes through the right wire passage 204 and is guided by the upper curl guide 56 to pass through the upper wire passage 60. After that, the tip of the wire W passes through the lower wire passage 62 and moves to the rear upper side. Next, as shown in Figure 12, the tip of the wire W passes through the left wire passage 206 and comes into contact with the wire tip guide surface 190.

[0064] As shown in Figure 15, when the tip of the wire W comes into contact with the wire tip guide surface 190, it is guided by the wire tip guide surface 190 and moves along the wire tip guide surface 190. In the first comparative example, where the wire tip guide surface 190 is not inclined with respect to the central axis CX, and in the second comparative example, where the wire tip guide surface 190 is inclined with respect to the central axis CX such that it moves away from the central axis CX as it moves from the front to the rear, the tip of the wire W moves along the wire tip guide surface 190 from the front to the rear. At this time, the tip of the wire W moves away from the reinforcing bar R. On the other hand, in this embodiment, the tip of the wire W moves in the direction of movement D5 from the rear to the front. At this time, the tip of the wire W moves in the direction of movement toward the reinforcing bar R. After moving along the wire tip guide surface 190, the tip of the wire W comes into contact with the guard surface 196. This prevents the tip of the wire W from coming out from between the left clamp member 156 and the clamp shaft 152. Subsequently, the feed unit 40 (see Figure 2) stops feeding the wire W. As a result, the wire W is wound around the reinforcing bar R. The tip of the wire W is located on the guard surface 196. Furthermore, the distance between the tip of the wire W and the reinforcing bar R in this embodiment is shorter than the distance between the tip of the wire W and the reinforcing bar R in the first and second comparative examples.

[0065] Next, the operation of gripping and twisting the wire W will be described. After the wire W is wound around the reinforcing bar R, the outer sleeve 106 shown in Figure 11 moves forward relative to the clamp shaft 152 as the screw shaft 102 rotates clockwise in direction D3 (see Figure 3). As a result, the left clamp member 156 moves to the right relative to the clamp shaft 152, and the tip of the wire W is clamped between the left clamp member 156 and the clamp shaft 152. Also, the right clamp member 154 moves to the left relative to the clamp shaft 152. At this time, the wire W is not clamped between the right clamp member 154 and the clamp shaft 152. Next, the feed unit 40 shown in Figure 2 pulls the wire W back toward the bobbin 32, causing the wire W around the reinforcing bar R to shrink in diameter and come into contact with the reinforcing bar R. After that, the outer sleeve 106 shown in Figure 7 moves further forward relative to the clamp shaft 152 as the screw shaft 102 rotates. At this time, the push member 110 pushes the second projection 92 of the second lever member 76 forward. As a result, the wire W is cut by the first cutter 70 and the second cutter 72 near the boundary between the first cutting opening 80 and the second cutting opening 82. Next, the outer sleeve 106 shown in Figure 8 moves further forward relative to the clamp shaft 152 as the screw shaft 102 rotates. As a result, the right clamp member 154 moves further left relative to the clamp shaft 152, and the wire W is clamped between the right clamp member 154 and the clamp shaft 152 near the cutting point. Next, the outer sleeve 106 moves further forward relative to the clamp shaft 152 as the screw shaft 102 rotates. When the fin portion 132 of the fin member 108 moves forward beyond the front end of the restricting piece 138a (see Figure 10) of the lower stopper 138 of the rotation limiting unit 48, the fin portion 132 no longer comes into contact with the restricting piece 138a. Therefore, rotation of the outer sleeve 106 is permitted, and the gripping unit 100 rotates together with the outer sleeve 106 around the central axis CX in a clockwise direction D3. As a result, the wire W is twisted, and the reinforcing bar R is tied together using the wire W.

[0066] As described above, before the wire W is twisted, the distance between the tip of the wire W and the reinforcing bar R in this embodiment is shorter than the distance between the tip of the wire W and the reinforcing bar R in the first and second comparative examples. Therefore, as shown in Figure 16, even after the wire W is twisted, the wire W ear height L1, which represents the distance between the tip of the wire W and the reinforcing bar R in this embodiment, is shorter than the wire W ear height L2 in the first and second comparative examples.

[0067] (effect) The rebar tying machine 2 of this embodiment ties reinforcing bars R using wire W. The rebar tying machine 2 includes a rotatable screw shaft 102, an outer sleeve 106 (an example of a sleeve) into which the screw shaft 102 is inserted and which is movable and rotatable in the front-rear direction, a fin member 108 attached to the outer sleeve 106 which allows and prohibits the rotation of the outer sleeve 106, a push member 110 attached to the outer sleeve 106 so as to be rotatable around the outer sleeve 106 and which does not rotate even when the outer sleeve 106 rotates, a cutting unit 44 (an example of an operated unit) which has a longitudinal direction in the front-rear direction and is operated by the push member 110 when the outer sleeve 106 moves in the front-rear direction, and a gripping unit 100 which protrudes from the front of the outer sleeve 106, is rotatable with the outer sleeve 106 and grips the wire W. The push member 110 is positioned in front of the fin member 108.

[0068] With the above configuration, since the push member 110 is positioned in front of the fin member 108, the space required for positioning the cutting unit 44 can be reduced in the front-to-back direction compared to a configuration in which the push member 110 is positioned behind the fin member 108. This increases the degree of freedom in positioning the cutting unit 44.

[0069] Furthermore, the cutting unit 44 includes a first lever member 74 or a second lever member 76 (an example of an operated member) to which the push member 110 can contact and which is operated by the push member 110 when contact is made, and a second cutter 72 (an example of a cutter) capable of cutting the wire W and which operates when the first lever member 74 or the second lever member 76 is operated by the push member 110.

[0070] The second cutter 72 needs to be positioned near the wire W in order to cut the wire W. With the above configuration, the push member 110 is positioned in front of the fin member 108, so the distance between the push member 110 and the reinforcing bar R is shorter compared to a configuration in which the push member 110 is positioned behind the fin member 108. This makes the cutting unit 44 smaller in the front-to-back direction.

[0071] Furthermore, the cutting unit 44 also includes a link member 78 that connects the first lever member 74 or the second lever member 76 to the second cutter 72.

[0072] With the above configuration, the link member 78 can be made smaller in the front-rear direction compared to a configuration in which the push member 110 is positioned behind the fin member 108.

[0073] Furthermore, the push member 110 is sandwiched between the outer sleeve 106 and the fin member 108 in the front-rear direction.

[0074] With the above configuration, the push member 110 can be attached to the outer sleeve 106 with a simple configuration.

[0075] Furthermore, the rebar tying machine 2 is further equipped with a trigger 24 that is pressed by the user. The trigger 24 is aligned with the cutting unit 44 when the rebar tying machine 2 is viewed in a left-right direction perpendicular to the front-back direction.

[0076] With the above configuration, compared to a configuration in which the trigger 24 is not aligned with the cutting unit 44 in the front-to-back direction when the rebar tying machine 2 is viewed in the left-to-right direction perpendicular to the front-to-back direction, it is possible to suppress the enlargement of the rebar tying machine 2 in the direction perpendicular to the front-to-back direction.

[0077] (Second example) In the second embodiment, only the differences from the first embodiment will be described. As shown in Figure 17, the wire tip guide surface 190 is substantially parallel to the first virtual surface 192. The distance between the wire tip guide surface 190 and the central axis CX is substantially the same between the front and rear ends of the wire tip guide surface 190. The wire tip guide surface 190 is substantially perpendicular to the second virtual surface 194. Furthermore, the wire tip guide surface 190 is substantially perpendicular to the guard surface 196.

[0078] As shown in Figure 18, the tip of the wire W has a wire tip surface 300. The wire tip surface 300 is inclined with respect to the longitudinal axis 304 of the wire W. The inclination angle A4 of the wire tip surface 300 with respect to the longitudinal axis 304 is greater than 90 degrees. The inclination angle A4 is the angle measured between the wire tip surface 300 and the longitudinal axis 304 when the wire W is divided in half by a plane containing the longitudinal axis 304. The inclination angle A4 is also the angle obtained by adding 90 degrees to the angle between the wire tip surface 300 and the cutting surface when the wire W is cut by a cutting surface perpendicular to the longitudinal axis 304. The inclination angle A4 may also be 95 degrees or greater. In this embodiment, the inclination angle A4 is 100 degrees. The tip of the wire W is sharply pointed. The wire tip surface 300 is formed by cutting the wire W with the first cutter 70 and the second cutter 72.

[0079] As shown in Figure 19, the pivot axis RX of the second cutter 72 passes through the first cutting opening 80 of the first cutter 70. A portion of the first cutting opening 80 is defined by a first cutting surface 310. The first cutting surface 310 is located at the end of the first cutting opening 80 on the side of the second cutting opening 82. The first cutting surface 310 is connected to the outer circumferential surface 312 of the first cutter 70. The first cutting surface 310 is substantially perpendicular to the longitudinal direction of the first cutting opening 80. A portion of the second cutting opening 82 of the second cutter 72 is defined by a second cutting surface 314. The second cutter 72 has an opposing surface 316 that faces the outer circumferential surface 312 of the first cutter 70, and the second cutting surface 314 is connected to the opposing surface 316. The angle between the second cutting surface 314 and the opposing surface 316 is acute, for example, 70 degrees or less. The wire W is cut by being sandwiched between the first cutting surface 310 and the second cutting surface 314.

[0080] Next, the behavior of the tip of the wire W moving on the wire tip guide surface 190 will be described. As shown in Figure 18, when the corner of the tip of the wire W contacts the wire tip guide surface 190, the wire tip surface 300 is inclined with respect to the wire tip guide surface 190. The inclination angle A5 of the wire tip surface 300 with respect to the wire tip guide surface 190 is greater than 0 degrees. The inclination angle A5 is the angle measured between the wire tip guide surface 190 and the wire tip surface 300. The inclination angle A5 may also be 5 degrees or more. In this embodiment, the inclination angle A5 is 10 degrees. As shown in Figure 20, the wire tip surface 300 then contacts the wire tip guide surface 190 with its surface. At this time, the longitudinal axis 304 of the wire W is inclined with respect to the wire tip guide surface 190 at an inclination angle A4. Next, as shown in Figure 17, the wire tip surface 300 moves on the wire tip guide surface 190 in the direction D6, from the rear to the front. At this time, the wire tip surface 300 moves in a direction toward the reinforcing bar R. After moving along the wire tip guide surface 190, the wire tip surface 300 comes into contact with the guard surface 196. Therefore, as shown in Figure 16, after the wire W is twisted, the ear height L1 of the wire W in this embodiment is shorter than the ear height L2 of the wire W in the first and second comparative examples.

[0081] (Third embodiment) In the third embodiment, only the differences from the second embodiment will be described. In the third embodiment, as shown in Figure 21, the first cutting opening 80 of the first cutter 70 is offset from the pivot axis RX of the second cutter 72. The first cutting opening 80 is located behind the pivot axis RX. The first cutting opening 80 extends in a straight line. The central axis 400 of the first cutting opening 80 is inclined at an acute angle with respect to the tangent 402 of the outer peripheral surface 312 at the intersection of the central axis 400 and the outer peripheral surface 312 of the first cutter 70. As the wire W is sandwiched and cut between the first cutting surface 310 and the second cutting surface 314, the wire tip surface 300 (see Figure 18) is inclined with respect to the longitudinal axis 304 of the wire W (see Figure 18).

[0082] (modified version) In one embodiment, the push member 110 may operate components other than the cutting unit 44.

[0083] In one embodiment, the push member 110 may be attached to the outer sleeve 106 by a screw or other component.

[0084] In one embodiment, the grip portion 16 may extend in the left-right direction.

[0085] In one embodiment, the rebar tying machine 2 may be equipped with a power cord that can be connected to an external power source instead of a battery pack BP. In this case, the rebar tying machine 2 operates using power supplied from an external power source via the power cord.

[0086] In one embodiment, the reel housing portion 22 may be located at the rear end of the twisting unit housing portion 14.

[0087] In one embodiment, the gripping unit 64 may include a pair of openable and closable hook members. In this case, the pair of hook members may grip the wire W when closed and release the wire W when opened. [Explanation of Symbols]

[0088] 2: Rebar tying machine 14: Twist unit housing 16: Grip section 22: Reel storage section 24: Trigger 28: Reel 32: Bobbin 40: Feed Unit 42: Information Unit 44: Cutting Unit 46: Twist Unit 48: Rotation limiting unit 70: First cutter 72: Second cutter 74: First lever member 76: Second lever member 78: Link member 90: First Pier 92: Second Pier 100: Gripping unit 102: Screw shaft 104: Inner Sleeve 106: Outer sleeve 108: Fin component 110: Push member 132: Fin section 152: Clamp shaft 154: Right-side clamp member 156: Left-side clamp member 190: Wire tip guide surface 192: First virtual surface 194: Second virtual plane 196: Guard surface 300: Wire tip surface 304: Long axis A1, A2, A4, A5: Inclination angle A3 : Angle AX: Long axis BP: Battery Pack CX: Central axis D5, D6: Movement direction L1, L2: Ear height R: Reinforcement bars W: wire WO: Wound orbit

Claims

1. A rebar tying machine that uses wire to tie together rebar, A rotatable screw shaft, The aforementioned screw shaft is inserted into a sleeve that is movable in the front-to-back direction and rotatable, A fin member attached to the sleeve, which allows and prohibits the rotation of the sleeve, A push member is attached to the sleeve so as to be rotatable around the sleeve, and does not rotate even when the sleeve rotates. The operated unit has a longitudinal direction in the front-rear direction and is operated by the push member when the sleeve moves in the front-rear direction, The system includes a gripping unit that protrudes from the front of the sleeve, is rotatable with the sleeve, and grips the wire, The push member is positioned in front of the fin member in the rebar tying machine.

2. The operated unit is, The push member is capable of contacting the operated member, and the operated member is operated by the push member when contact is made. The rebar tying machine according to claim 1, further comprising a cutter capable of cutting the wire and operating when the operated member is operated by the push member.

3. The rebar tying machine according to claim 2, wherein the operated unit further comprises a link member connecting the operated member and the cutter.

4. The rebar tying machine according to claim 1, wherein the push member is sandwiched between the sleeve and the fin member in the front-rear direction.

5. It also features a trigger that can be pressed by the user, The rebar tying machine according to any one of claims 1 to 4, wherein the trigger is aligned with the operated unit in the front-to-back direction when the rebar tying machine is viewed in a direction perpendicular to the front-to-back direction.

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