Binding Machine

This application is based on and claims priority under 35 USC § 119 from Japanese Patent Application No. 2024-073421 filed on Apr. 30, 2024, the contents of which are incorporated herein by reference.

The present disclosure relates to a binding machine for binding a to-be-bound object such as a reinforcing bar with a wire.

For concrete buildings, reinforcing bars are used so as to improve strength. The reinforcing bars are bound with wires so that the reinforcing bars do not deviate from predetermined positions during concrete placement.

In the related art, suggested is a binding machine referred to as a reinforcing bar binding machine configured to wind a wire on two or more reinforcing bars and to twist the wire wound on the reinforcing bars, thereby binding the two or more reinforcing bars with the wire.

The binding machine guides the wire fed by a drive force of a motor and curled to a binding portion, which twists the wire by a guide called a curl guide or the like, and twists the wire wound around the reinforcing bars by the binding portion, thereby binding the reinforcing bars with the wire. In order to guide the curled wire to the binding portion, a binding machine is suggested which has a guiding facilitation part that comes into contact with a wire from a radially outer side of a loop formed by the curled wire and applies, to the wire, a force that changes a feeding path of the wire (for example, see Patent Literature 1).

In addition, when a diameter of the reinforcing bars to be bound with the wire increases, it is necessary to increase a diameter of the feeding path of the wire that is wound in an annular shape around the reinforcing bars. Therefore, a reinforcing bar binding machine is suggested which can reliably guide the wire to the binding portion even when the diameter of the feeding path of the wire, which becomes an annular shape, increases (for example, see Patent Literature 2).

Patent Literature: JP2022-164438A

Patent Literature: JP7302302B

In the binding machine of the related art in which the diameter of the reinforcing bars to be bound with the wire is small and the diameter of the feeding path of the wire, which is wound in an annular shape, is also small, the wire guided to the curl guide passes through a path spaced from a bottom surface portion of the curl guide. In contrast, when the diameter of the feeding path of the wire, which is wound in an annular shape, increases, a tip of the wire guided to the curl guide comes into contact with the bottom surface portion of the curl guide. For this reason, the resistance caused by friction when the wire slides along the bottom surface portion increases, potentially making it impossible to feed the wire to the binding portion.

An object of the present disclosure is to provide a binding machine configured to be able to reliably guide a wire whose tip is in contact with a bottom surface portion of a curl guide.

An aspect of the present disclosure is a binding machine including: a wire feeding portion configured to feed a wire; a curl forming portion configured to form an annular feeding path for winding the wire fed by the wire feeding portion around a to-be-bound object; and a binding portion configured to twist the wire wound on the to-be-bound object. The curl forming portion includes an arm part configured to curl the wire fed by the wire feeding portion, and a curl guide part configured to guide the wire curled by the arm part to the binding portion. The curl guide part includes a bottom surface portion on a radially outer side of the annular feeding path. The bottom surface portion includes a guiding portion forming at least a part of a tip portion side of the curl guide part and configured to guide a tip of the wire toward a base end portion side of the curl guide part.

In addition, another aspect of the present disclosure is a binding machine including: a wire feeding portion configured to feed a wire; a curl forming portion configured to form an annular feeding path for winding the wire fed by the wire feeding portion around a to-be-bound object; and a binding portion configured to twist the wire wound on the to-be-bound object. The curl forming portion includes an arm part configured to curl the wire fed by the wire feeding portion, and a curl guide part configured to guide the wire curled by the arm part to the binding portion. The curl guide part includes a bottom surface portion on a radially outer side of the annular feeding path, the bottom surface portion includes a guiding portion forming at least a part of a tip portion side of the curl guide part, the guiding portion has an inclined surface inclined with respect to the bottom surface portion in a direction in which a first end portion on the tip portion side of the curl guide part becomes closer to the arm part than a second end portion on a base end portion side of the curl guide part. The inclined surface is configured such that a dimension of the first end portion with respect to the second end portion is longer in a direction parallel to a virtual extension line of the bottom surface portion than in a direction orthogonal to the virtual extension line of the bottom surface portion.

Hereinafter, an example of a reinforcing bar binding machine as an embodiment of the binding machine of the present disclosure will be described with reference to the drawings.

is an internal configuration view showing an example of a reinforcing bar binding machine of the present embodiment, as viewed from a side,is a side view of main parts showing the example of the reinforcing bar binding machine of the present embodiment, andis an appearance side view showing the example of the reinforcing bar binding machine of the present embodiment. In addition,are appearance perspective views showing the example of the reinforcing bar binding machine of the present embodiment.

A reinforcing bar binding machineA has such a shape that an operator grips with a hand, and includes a main body partand a handle part. In addition, the reinforcing bar binding machineA feeds wires W in a forward direction indicated by an arrow F, winds the wires around reinforcing bars S, which are a to-be-bound object, feeds the wires W wound around the reinforcing bars S in a reverse direction indicated by an arrow R, winds the wires on the reinforcing bars S, and twists the wires W, thereby binding the reinforcing bars S with the wires W. The reinforcing bar binding machineA binds the reinforcing bars S with a plurality of wires W, in this example, two wires W.

In order to implement the above-described functions, the reinforcing bar binding machineA includes a magazinein which the wires W are accommodated, a wire feeding portionthat feeds the wires W, and a wire guide portionthat guides the wires W, which are fed by the wire feeding portion. In addition, the reinforcing bar binding machineA includes a curl forming portionthat forms an annular feeding path for winding the wires W, which are fed by the wire feeding portion, around the reinforcing bars S, and a cutting portionthat cuts the wires W wound on the reinforcing bars S. In addition, the reinforcing bar binding machineA includes a binding portionthat twists the wires W wound on the reinforcing bars S, and a drive portionA that drives the binding portion. In addition, the reinforcing bar binding machineA includes a tip guide part(L,R) against which the reinforcing bars S are butted and which supports the curl forming portion.

The magazineis an example of an accommodation portion, and a reelon which the long wires W are wound to be reeled out is rotatably and detachably accommodated therein. For the wire W, a wire made of a plastically deformable metal wire, a wire having a metal wire covered with a resin, or a twisted wire is used. In a configuration in which the reinforcing bars S are bound with two wires W, the two wires W are wound on the reeland can be pulled out at the same time from the reel.

The wire feeding portionincludes a pair of feeding gearsthat sandwiches and feeds the wires W. In the wire feeding portion, a rotating operation of a feeding motor (not shown) is transmitted to the feeding gears, causing the feeding gearsto rotate. Additionally, in the wire feeding portion, a rotation direction of the feeding motor (not shown) is switched between forward and reverse directions to switch a rotation direction of the feeding gears, thereby switching a feeding direction of the wires W between the forward and reverse directions. In the configuration where the reinforcing bars S is bound with two wires W, the wire feeding portionaligns the two wires W in a radial direction of the wires W and feeds the wires.

The wire guide portionis arranged on upstream and downstream sides of the feeding gearswith respect to the feeding direction of the wires W that are fed in the forward direction. In the configuration where the reinforcing bars S are bound with two wires W, the wire guide portionaligns the two entering wires W in parallel along a direction in which the pair of feeding gearsis aligned and guides the same between the pair of feeding gears.

The curl forming portionincludes an arm partthat curls the wires W, which are fed by the wire feeding portion, and a curl guide partthat guides the wires W curled by the arm partto the binding portion. The curl forming portioncurls the wires W, which are fed by the wire feeding portionand pass through the arm part, by the arm partand guides the wires W curled by the arm partto the binding portionby the curl guide part. Thereby, the curl forming portionforms a feeding path of the wires W, represented by a two-dot chain line, passing through the curl guide partfrom the arm partand reaching the binding portion. The feeding path of the wires W passing through the curl guide partfrom the arm partand reaching the binding portionis called an annular feeding path Ru.

The arm parthas a groove portionwhich has a width through which the wires W pass and is formed along a circumferential direction of the annular feeding path Ru. In the configuration where the reinforcing bars S are bound with two wires W, the arm partaligns the two entering wires W in parallel in a direction in which the wires are aligned along an axial direction of the annular feeding path Ru.

The curl guide parthas a width-expanding portion, into which the wires W curled by the arm partenter, and a return guide portion, which guides the wires W entering the width-expanding portionto the binding portion.

The width-expanding portionhas a bottom surface portionprovided on a radially outer side of the annular feeding path Ru, and side surface portionsprovided on both sides in the axial direction of the annular feeding path Ru.

The bottom surface portionhas a guiding portionwhich constitutes at least a part of a tip portionside of the curl guide part.

The guiding portionhas an inclined surfaceprovided on a trajectory, along which the tips of the wires W entering the width-expanding portionpass, on the radially outer side of the annular feeding path Ru. The inclined surfaceof the guiding portionis configured as a flat surface in the present example. In the guiding portionthe inclined surfaceextends from a tip portionside of the curl guide parttoward a base end portionside of the curl guide part, which is an end portion on the binding portionside, by a length, within which the tips of the wires W entering the width-expanding portionare assumed to come into contact with the inclined surface, and connects to the bottom surface portion

In the guiding portionthe inclined surfaceis inclined with respect to the bottom surface portionin a direction in which a first end portion, which is an end portion on the tip portionside of the curl guide part, becomes closer to the arm partthan a second end portion, which is an end portion on the bottom surface portionside.

The inclined surfaceis configured such that a dimension of the first end portionrelative to the second end portionis longer in a direction parallel to a virtual extension line of the bottom surface portionthan in a direction orthogonal to the virtual extension line of the bottom surface portionThat is, the guiding portionis configured such that a length L of the inclined surfacefrom the first end portionto the second end portionalong a direction parallel to a plane of the bottom surface portionis greater than a height H of the first end portionof the inclined surfacerelative to the bottom surface portionalong a direction intersecting the plane of the bottom surface portion

Thereby, in the guiding portionthe inclined surfaceextends along the circumferential direction of the annular feeding path Ru on the tip portionside of the curl guide partwith respect to the bottom surface portionIn the guiding portiona cross-sectional shape of the inclined surfacein a direction parallel to the annular feeding path Ru, that is, a cross-sectional shape of the inclined surfacewhen the curl guide partis viewed from a side along the axial direction of the annular feeding path Ru extends, in the present example, in a straight line shape in a predetermined direction along the circumferential direction of the annular feeding path Ru.

In addition, the bottom surface portionextends along the circumferential direction of the annular feeding path Ru on the base end portionside of the curl guide portionwith respect to the guide portionThe bottom surface portionwhen the curl guide partis viewed from a side along the axial direction of the annular feeding path Ru, has a cross-sectional shape extending in a straight line in a predetermined direction along the circumferential direction of the annular feeding path Ru, in the present example, in a tangential direction of a vertex of a portion of the annular feeding path Ru facing the bottom surface portion

The side surface portionsandinclude first side surface portions(L,R), which are composed of surfaces with parallel spacing, and second side surface portions(L,R), which are composed of surfaces with spacing that narrows from the tip portionside toward the base end portionside of the curl guide part.

The first side surface portionsL andR extend from the tip portionof the curl guide parttoward the base end portionside of the curl guide partby a predetermined length.

The first side surface portionsL andR and the second side surface portionsL andR protrude toward a radially inner side of the annular feeding path Ru with respect to the inclined surfaceof the guiding portionand the bottom surface portion

In the side surface portionsandthe entirety of the first side surface portionsL andR and parts of the second side surface portionsL andR on sides connecting to the first side surface portionsL andR are provided on both side portions of the inclined surfaceIn addition, in the side surface portionsandthe remainders of the second side surface portionsL andR are provided on both side portions of the bottom surface portion

Thereby, the guiding portionhas a shape in which a width of the inclined surfaceis the same at the portions where the first side surface portionsL andR are provided on both sides. In addition, the guiding portionhas a shape in which a width of the inclined surfacegradually narrows from the tip portionside toward the base end portionside of the curl guide partat the portions where the second side surface portionsL andR are provided on both sides. The bottom surface portionhas a shape in which a width gradually narrows from the tip portionside toward the base end portionside of the curl guide part.

In the side surface portionsandthe first side surface portionL and the second side surface portionL and the inclined surfaceof the guiding portionare in contact with each other, respectively so as to prevent the wire W from entering between the first side surface portionL and the second side surface portionL and the inclined surfaceof the guiding portionNote that a gap narrower than a diameter of the wire W may be formed between the first side surface portionL and the second side surface portionL and the inclined surfaceof the guiding portion

Additionally, in the side surface portionsandthe first side surface portionR and the second side surface portionR and the inclined surfaceof the guiding portionare in contact with each other, respectively, so as to prevent the wire W from entering between the first side surface portionR and the second side surface portionR and the inclined surfaceof the guiding portionNote that a gap narrower than the diameter of the wire W may be formed between the first side surface portionR and the second side surface portionR and the inclined surfaceof the guiding portion

In the side surface portionsandthe second side surface portionL and the bottom surface portionare in contact with each other so as to prevent the wire W from entering between the second side surface portionL and the bottom surface portion. Note that a gap narrower than the diameter of the wire W may be formed between the second side surface portionL and the bottom surface portion

Additionally, in the side surface portionsandthe second side surface portionR and the bottom surface portionare in contact with each other so as to prevent the wire W from entering between the second side surface portionR and the bottom surface portionNote that a gap narrower than the diameter of the wire W may be formed between the second side surface portionR and the bottom surface portion

The return guide portionhas an inclined portionprovided on the radially outer side of the annular feeding path Ru, and side surface portions(L,R) provided on both sides in the axial direction of the annular feeding path Ru.

The inclined portionis configured as a surface inclined with respect to the bottom surface portionin the direction toward the binding portionalong the circumferential direction of the annular feeding path Ru. The inclined portionextends along the circumferential direction of the annular feeding path Ru on the base end portionside of the curl guide partwith respect to the bottom surface portionThe inclined portionwhen the curl guide partis viewed from a side along the axial direction of the annular feeding path Ru, extends in a straight line in a predetermined direction along the circumferential direction of the annular feeding path Ru, in the present example, in a tangential direction of the annular feeding path Ru.

The side surface portionsL andR are composed of surfaces with parallel spacing along the direction in which the inclined portionextends. The side surface portionsL andR protrude toward the radially inner side of the annular feeding path Ru with respect to the inclined portionIn the configuration where the reinforcing bars S are bound with two wires W, the return guide portionhas the side surface portionsL andR facing each other at a distance of about twice the diameter of the wire W, and aligns the two entering wires W in parallel in the direction in which the wires are aligned along the axial direction of the annular feeding path Ru.

In the curl guide part, the bottom surface portionfirst side surface portionsL andR, and second side surface portionsL andR of the width-expanding portion, and the side surface portionsL andR of the return guide portionare formed integrally by press processing of sheet metal such as iron. Additionally, in the curl guide part, the guiding portionmanufactured in a predetermined shape using a plate material such as iron is fixed to the bottom surface portionby welding or the like. Additionally, in the curl guide part, a plate material, such as iron, formed with the inclined portionis fixed between the side surface portionsL andR by a fastening member. Note that in the curl guide part, the guiding portionmay be configured integrally with the bottom surface portionby press processing or the like.

The cutting portionincludes a fixed blade part, a movable blade partthat cuts the wires W in cooperation with the fixed blade part, and a transmission mechanismthat transmits an operation of the binding portionto the movable blade part. The cutting portioncuts the wires W by a rotating operation of the movable blade partabout the fixed blade partas a fulcrum shaft.

The binding portionincludes a wire locking bodyto which the wires W are locked, and a sleevefor actuating the wire locking body. The drive portionincludes a twist motorand a deceleratorthat performs deceleration and torque amplification.

In the reinforcing bar binding machineA, the handle partextends downward from the main body part. In addition, a batteryis detachably mounted to a lower part of the handle part. In addition, in the reinforcing bar binding machineA, the magazineis provided in front of the handle part.

In the reinforcing bar binding machineA, a triggeris provided on a front side of the handle part, and a switchis provided inside the handle part. In the reinforcing bar binding machineA, a control portioncontrols the twist motorand the feeding motor (not shown), in response to a state of the switchthat is pressed by an operation on the trigger.

The tip guide partL is provided at a front end portion of the main body part, on one side. The tip guide partL includes a butting portionLa against which the reinforcing bars S are butted, an arm support portionL supported by the arm part, a curl guide support portionL supported by the curl guide part, and a main body support portionL supported by the main body part.

In the tip guide partL, the arm support portionL is fixed to the arm partby screwsAdditionally, in the tip guide partL, the curl guide support portionL is fixed to the curl guide partby a screwAdditionally, in the tip guide partL, the main body support portionL is fixed to the main body partby screws

The tip guide partR is provided at a front end portion of the main body part, on the other side. The tip guide partR includes a butting portionRa against which the reinforcing bars S are butted, an arm support portionR supported by the arm part, a curl guide support portionR supported by the curl guide part, and a main body support portionR supported by the main body part.

In the tip guide partR, the arm support portionR is fixed to the arm partby screwsAdditionally, in the tip guide partR, the curl guide support portionR is fixed to the curl guide partby a screwAdditionally, in the tip guide partR, the main body support portionR is fixed to the main body partby screws