EP2996201A1

EP2996201A1 - Terminal for electric wire joining connector and electric wire joining connector having same

Info

Publication number: EP2996201A1
Application number: EP14794644.6A
Authority: EP
Inventors: Younghwan Lee
Original assignee: Jowx Corp
Current assignee: Jowx Corp
Priority date: 2013-05-08
Filing date: 2014-02-27
Publication date: 2016-03-16
Also published as: EP2996201A4; WO2014181957A1; KR101422082B1; RU2015151333A; MX2015015418A; RU2627738C2; TW201444207A

Abstract

Disclosed is a terminal for an electric wire joining connector, comprising: a cutting mounting part; a hook protrusion; and a central connection band. The cutting mounting part comprises: a plurality of erection pieces, disposed along the longitudinal direction of a wire, having blades thereon which face each other; and a connection piece connecting the lower portions of the erection pieces. The hook protrusion, disposed between the erection pieces, protrudes from the upper surface of the corresponding connection piece. The central connection band interconnects at least two cutting mounting parts. The terminal for an electric wire joining connector of the present invention is economical, since the terminal can join electric wires without using any separate tool and can simultaneously connect a plurality of wires. Furthermore, due to having a conductive member inside and an insulating member outside, the terminal for an electric wire joining connector of the present invention does not include a separate insulating sheath, and thus it is simple to assemble the terminal. In addition, by means of the hook protrusion, it is possible to improve resistance to the axial tensile force of the wires.

Description

[Technical Field]

The present invention relates to a terminal for an electric wire joining connector and an electric wire joining connector with the same. More particularly, the present invention relates to a terminal for an electric wire joining connector and an electric wire joining connector with the same which can electrically connect electric wires with no need to strip a sheath of the electric wires, increase contact areas with the electric wires via a hook protrusion, and increase a resistance force against a tensional force in a direction of the electric wires.

[Background Art]

A method of connecting two or more separate electric wires including steps of stripping sheaths of the electric wires, joining exposed core wires to each other, and then wrapping the joined portion with an insulating tape is widely used.
A tool for twisting or twining the core wires is needed to connect two or more separate electric wires, and when two or more wires are wrapped with insulating tape, the operation of joining the electric wires may be complex and an accident of electric shock may occur.
In addition, a resistance force of the connected electric wires against a tensional force in a direction of the electric wires is substantially decreased, and the electric wires may be disconnected when a tensional force is applied in a longitudinal direction of the connected electric wires.

[Disclosure]

[Technical Problem]

The present invention is directed to provide a terminal for an electric wire joining connector and an electric wire joining connector with the same, which can rapidly and easily electrically connect electric wires with no need to strip a sheath of the electric wires and without any specific tool, increase contact areas with the electric wires via a hook protrusion, and increase a resistance force against a tensional force in a direction of the electric wires.

[Technical Solution]

One aspect of the present invention provides a terminal for an electric wire joining connector including: a cutting mounting part having a plurality of erection pieces and a connection piece which connects lower portions of the erection pieces, the erection pieces being provided along a length of an electric wire and having cutting edges facing each other formed thereon; a hook protrusion protruding from an upper surface of the connection piece between the erection pieces; and a central connection band which connects at least two of the cutting mounting parts to each other.
The hook protrusion of the terminal for the electric wire joining connector has a shape that is wider in a lower portion and narrows upward.
The hook protrusion of the terminal for the electric wire joining connector has a triangular pyramidal shape with a wide width and a narrow thickness.
The hook protrusion of the terminal for the electric wire joining connector passes a sheath of the electric wire and is electrically connected to a core wire disposed within the electric wire.
It further includes a plurality of connectors which sequentially connect upper portions and opposite lower portions of the erection pieces spaced in the longitudinal direction of the electric wire of the terminal for the electric wire joining connector, thereby integrally connecting the erection pieces.
A direction of the cutting edge of the cutting mounting part formed on a side of the central connection band of the terminal for the electric wire joining connector and a direction of the cutting edge of the cutting mounting part formed on an opposite side of the central connection band are parallel to each other.
The direction of the cutting edge of the cutting mounting part formed on a side of the central connection band of the terminal for the electric wire joining connector and the direction of the cutting edge of the cutting mounting part formed on an opposite side of the central connection band are formed to be perpendicular to each other.
Shape deformation preventing portions which prevent deformation of the shape of the hook protrusion due to a load applied to the hook protrusion are formed on the upper surface of the connection piece which corresponds to both sides of the hook protrusion of the terminal for the electric wire joining connector.
Another aspect of the present invention provides an electric wire joining connector including: a terminal having a cutting mounting part having a plurality of erection pieces and a connection piece which connects lower portions of the erection pieces, the erection pieces being provided along a length of an electric wire and having cutting edges facing each other formed thereon, a hook protrusion protruding from an upper surface of the connection piece between the erection pieces, and a central connection band which connects at least two of the cutting mounting parts; a lower connector in which a space for accommodating the electric wire and the terminal is formed; and an upper connector which is coupled to the lower connector and hinged to feed the electric wire to the terminal.
The hook protrusion of the electric wire joining connector has a shape that is wider in a lower portion and narrows upward.
The hook protrusion of the electric wire joining connector has a triangular pyramidal shape with a wide width and a narrow thickness.
The hook protrusion of the electric wire joining connector passes a sheath of the electric wire and is electrically connected to a core wire disposed within the electric wire.
The electric wire joining connector further includes a plurality of connectors which sequentially connect upper portions and opposite lower portions of the erection pieces spaced in the longitudinal direction of the electric wire.
A direction of the cutting edge of the cutting mounting part formed on a side of the central connection band of the electric wire joining connector and a direction of the cutting edge of the cutting mounting part formed on an opposite side of the central connection band are formed to be parallel to each other.
The direction of the cutting edge of the cutting mounting part formed on a side of the central connection band of the electric wire joining connector and the direction of the cutting edge of the cutting mounting part formed on an opposite side of the central connection band are formed to be perpendicular to each other.

[Advantageous Effects]

According to an exemplary embodiment of the present invention, electric wires can be joined without a separate tool, a plurality of electric wires can be economically connected simultaneously, and a simple assembling operation can be achieved because an inner conducting member and an outer insulating member are included and thus there is no need to include a separate insulating sheath.
In addition, a resistance force against a tensional force in a direction of the electric wires can be enhanced by a hook protrusion.

[Description of Drawings]

FIG. 1 illustrates a perspective view of an electric wire joining connector having a terminal for an electric wire joining connector according to an exemplary embodiment of the present invention.
FIG. 2 illustrates a perspective view of a terminal for an electric wire joining connector according to another exemplary embodiment of the present invention.
FIG. 3 illustrates a perspective view of a terminal for an electric wire joining connector according to yet another exemplary embodiment of the present invention.
FIG. 4 illustrates a perspective view of a terminal for an electric wire joining connector according to still another exemplary embodiment of the present invention.

[Modes of the Invention]

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that a person skilled in the art may easily implement the present invention.
However, the present invention may be implemented in a variety of different forms and is not limited to the exemplary embodiments disclosed herein.
In the drawings, a description which are not related to a description for clearly describe the present invention is omitted, and the same or like parts are denoted with the same reference numbers throughout this specification.
It will be further understood that the term "comprises" in this specification specifies the presence of a stated constituent, but does not preclude the presence or addition of another constituent.
A terminal for an electric wire joining connector according to the present invention is formed by coupling an upper connector, a lower connector, and an internal terminal, and presents a structure capable of electrically and mechanically connecting electric wires without removal of separated sheaths of the electric wires.
An electric wire joining connector having the terminal for the electric wire joining connector according to an embodiment of the present invention will be described below with reference to FIG. 1.
FIG. 1 is a perspective view of the electric wire joining connector having the terminal for the electric wire joining connector according to the embodiment of the present invention.
Referring to FIG. 1, the electric wire joining connector according to the embodiment of the present invention includes a lower connector 10, an upper connector 20, and a terminal 30.
The lower connector 10 is a receptor with an opened upper surface and, for example, has a shape that extends long in a lengthwise direction. A space capable of accommodating the terminal 30 and the electric wire 40 is formed in the lower connector 10.
Shaft supports 11, each of which has a through hole shape, are formed at both sides of a center of the lower connector 10, and the shaft supports 11 are formed to face each other.
Here, the shaft supports 11 are coupled with a fixing shaft 21 of the upper connector 20, and the upper connector 20 and the lower connector 10 are coupled to each other by the shaft supports 11 and the fixing shaft of the upper connector 20.
A plurality of hook protrusions 12 protruding upward and then bent to protrude outward at an upper end thereof are formed at both ends of a bottom surface of the lower connector 10.
The plurality of the hook protrusions 12 are formed to face each other, and four hook protrusions 12 are formed at the both ends of the bottom surface of the lower connector 10 as shown in FIG. 1.
Electric wire supports 13, which are formed in a hemispherical shape to surround and support an outer surface of the electric wire 40, are formed at the both ends in the lengthwise direction of the lower connector 10.
The upper connector 20 is a receptor with an opened lower surface, has a shape that extends long in a lengthwise direction, and couples with the lower connector 10 accommodating the terminal 30 and the electric wire 40.
The fixing shafts 21 coupled to the shaft supports 11 formed at the lower connector 10 are formed at a center portion of the upper connector 20.
Fixing holes 22 into which the hook protrusions 12 of the lower connector 10 are inserted are formed at both sides which face each other of the upper connector 20. The hook protrusions 12 of the lower connector 10 and the fixing holes 22 of the upper connector 20 may couple to each other in a mutually hooking manner.
A hemispherical electric wire support 23 that supports and surrounds and supports the electric wire 40 is formed at a position on the upper connector 20 corresponding to the electric wire support 13 of the lower connector 10. The electric wire support 23 of the upper connector 20 and the electric wire support 13 of the lower connector 10 are formed to face each other, and the electric wire support 23 of the upper connector 20 and the electric wire support 13 of the lower connector 10 surround and fix the electric wire 40 while they engage with each other.
Folding sides (shown as dotted lines) which are disposed symmetrically with respect to the fixing shaft 21 and have a small thickness so as to be rotated toward the lower connector 10 together with the electric wire are formed at the upper connector 20.
A guide hole 25 is formed at the inside of the bottom surface of the upper connector 20, the guide hole 25 is formed at a position which is arranged with the hook protrusion 12, and one or more of the guide holes 25 are formed in at least one of regions divided based on the fixing shaft 21.
The guide hole 25 has a larger diameter than the electric wire 40 so that the electric wire 40 which has passed the electric wire supports 23 and 13 of the upper and lower connectors 20 and 10 passes through the inside of the guide hole 25.
A fixing piece (not shown) having a plate shape and protruding downward to press and fix the upper surface of the terminal 30 may be formed at the lower surface of the central portion of the upper connector 20, and the fixing piece may be formed in a shape corresponding to the shape of the terminal 30.
The upper connector 20 and the lower connector 10 may be made of a plastic material for the purpose of fixing by the hook protrusion 12 and the fixing hole 22 and by the fixing shaft 21 and the shaft support 11.
The terminal 30 for the electric wire joining connector is formed in an I shape in order to connect the two electric wires 40, and both regions of the terminal 30 for the electric wire joining connector partitioned based on the fixing shaft 21 are formed to be symmetric to each other.
The terminal 30 includes a cutting mounting part 31, connectors 32 and 33, and a central connection band 34, and the terminal 30 is formed, for example, in the shape of a thin iron band.
The cutting mounting part 31 includes a pair of erection pieces 31 a and a connection piece 31b which connect lower portions of the pair of erection pieces 31 a, the erection pieces 31a being provided at regular intervals in a widthwise direction and forming an electric wire receiving space 31 a2 between cutting edges 31a1 facing each other, and the plurality of erection pieces 31a are disposed at a predetermined interval in the lengthwise direction in which the electric wire 40 is disposed. The erection pieces 31a disposed at predetermined intervals are disposed to face each other.
In the cutting edges 31a1 facing each other, the width between the cutting edges 31a1 becomes narrow from an upper end of the erection piece 31 a toward a lower end of the erection piece 31 a, and has a Y shape that extends in parallel with each other up to the lower connection piece 31b of the erection piece 31 a while maintaining a constant interval at a central portion based on a height direction of the erection piece 31a.
That is, the cutting edges 31a1 formed at the erection pieces 31a are formed in an inclined shape so that a sheath of the electric wire is cut more easily.
The connectors 32 and 33 mutually connect cutting mounting part 31s spaced apart from each other in the lengthwise direction so that the electric wire 40 does not interfere with the connectors when the electric wire is inserted vertically into the electric wire receiving space 31a2, the connectors 32 and 33 connect the upper end and the lower end of the cutting mounting parts 31, respectively, and thus the erection pieces 31 a are connected to each other.
In this embodiment, four cutting mounting parts 31 are formed at both ends of the central connection band 34 based on the central connection band 34, respectively. In the case of describing the cutting mounting parts 31 of the one end of them, the first and second cutting mounting parts 31 are connected to the third and fourth cutting mounting parts 31 among the four cutting mounting parts at upper ends thereof by short rod-shaped connectors 32, respectively, and the second and third cutting mounting parts 31 are connected at lower ends thereof by a wide plate-shaped connector 33, respectively, thereby forming a structure in which all of the plurality of cutting mounting parts 31 are integrally connected.
The central connection band 34 has the form of a long band which connects both of the cutting mounting parts 31 to each other in a state in which the cutting mounting parts 31 is disposed at the both sides thereeof to each other.
In addition, hook protrusions 35 that are in contact with a core wire 41 in the electric wire and exchange electric power with each other, and simultaneously hook and fix the sheath 42 in the lengthwise direction after penetrating the lower surface of the sheath 42 of the electric wire 40 which is inserted into the electric wire receiving space 31a2 of the cutting mounting part 31 are provided at upper surfaces of each of the connection pieces 31b of the cutting mounting parts 31.
The hook protrusions 35 have triangular pyramidal shapes with wide lower portions and narrow upper portions, and a wide width and a narrow thickness.
In one embodiment of the present invention, the terminal 30 is formed of a metal that is a conductive material so as to exchange electric power with each other. The terminal 30 may be made of a copper alloy such as phosphor bronze that has a large strength and a lower degeneration property.
The terminal 30 may have a predetermined thickness depending on critical resistance of the electric wire 40 to be inserted.
The terminal 30 for the electric wire joining connector applied to one embodiment of the present invention is disposed in the lower connector 10, as shown in FIG. 1.
The terminal 30 is pressed and locked by a fixing piece (not shown) of the upper connector 30 which is assembled to the lower connector 10.
The upper connector 20 and the lower connector 10 are assembled while the fixing shaft 21 of the upper connector 20 is inserted and locked into the shaft support 11 of the lower connector 10.
Inner portions of the upper surfaces of the upper connectors 20 are exposed when both ends of the upper connectors 20 are folded upward about folding sides of the upper connectors 20, and then each of the electric wires 40 passes through the exposed guide holes 25 of the upper connectors 20.
The upper connectors 20 and the lower connector 10 are coupled to each other as the opened upper connectors 20 are rotated toward the lower connector 10 after two electric wires 40 are inserted into the exposed both guide holes 25, respectively.
At this time, the plurality of hook protrusions 12 of the lower connector 10 are coupled with the fixing holes 22 of the upper connector 20 so that the upper connector 20 and the lower connector 10 remain locked.
When the upper connector 20 and the lower connector 10 are coupled, the guide hole 25 of the upper connector 20 is arranged on the same line as the cutting edges 31a1 of the terminal 30 by pressing downward, and the sheath 42 of the electric wire 40 which passes through the guide hole 25 is simultaneously cut by the cutting edges 31a1 so that the core wire 41 is securely locked between the cutting edges 31a1 of the terminal 30.
At the same time, the sharp hook protrusions 35 of each connection piece 31b reach and are electrically connected to the core wire 41 in the electric wire 40 after the sharp hook protrusions 35 on each connection piece 31b penetrate the lower surface of the sheath 42 of the electric wire 40 so that conductivity is increased, and a resistance force against a pulling force in the direction of the electric wire 40 is simultaneously provided by perpendicular hooking of the sharp hook protrusions 35 and the sheath 42 so that the electric wire 40 is securely fixed to the terminal 30.
Through this, as a result, the electric wire 40 on one side and the other electric wire 40 on the other side may be electrically connected and securely fixed physically via the terminal 30.
Thus, the terminal for the electric wire joining connector of the present invention is an I-shaped terminal for an electric wire joining connector, and when the upper connectors 20 are pressed and coupled to the lower connector 10 in a state in which the two electric wires 40 are inserted into the both guide holes 25 of the upper connector 20, while the electric wire 40 is pressed downward, the sheath 42 is cut by and hooked to the cutting edge 31a1, the plurality of hook protrusions 35 are simultaneously inserted into the inside through the lower surface of the sheath 42 and come in contact with the core wire 41, and the hook protrusions 35 are simultaneously fixed securely with the sheath 42 and do not fall out. In addition, a contact area with the electric wire is increased so that the terminal can also be applied to an apparatus using high voltage and high current.
When the terminal for the electric wire joining connector has the form of an I shape, a direction of the cutting edge of the cutting mounting part formed on a side of the central connecting band and a direction of the cutting edge of the cutting mounting part formed on an opposite side to the one side of the central connection band are formed to be parallel to each other.
On the other hand, a terminal for an electric wire joining connector according to another embodiment of the present invention will be described with reference to FIG. 2.
FIG. 2 is a perspective view of another embodiment of a terminal for an electric wire joining connector of the electric wire joining connector shown in FIG. 1.
Referring to 2, the terminal for the electric wire joining connector according to another embodiment of the present invention is used to connect two electric wires in a T shape, and the terminal for the electric wire joining connector is a part that electrically connects a first electric wire running in one direction and a second electric wire running in a direction perpendicular to that of the first electric wire.
The T-shaped terminal 50 for the electric wire joining connector has the same structure as the above-described embodiment in that the terminal 50 for the electric wire joining connector includes a cutting mounting part 51 having a cutting edge 51a, connectors 52 and 53 which connect an upper end and a lower end of the cutting mounting part 51, a central connection band 54, and a hook protrusion 55, but has a different structure from the above-described embodiment in that a general shape of the terminal for the electric wire joining connector is a T shape. Accordingly, as a configuration of the terminal 50 is almost the same as that of the terminal 30 shown in FIGS 1 and 2, a detailed description thereof is omitted.
In one embodiment of the present invention, when the terminal for the electric wire joining connector has a T shape, a direction of the cutting edge of the cutting mounting part formed on a side of the central connection band and a direction of the cutting edge of the cutting mounting part formed on an opposite side to the one side of the central connection band are formed to be perpendicular to each other.
In addition, FIG. 3 is a perspective view of yet another embodiment of a terminal for an electric wire joining connector of the electric wire joining connector shown in FIG. 2.
Referring to FIG. 3, the terminal 60 for the electric wire joining connector according to yet another embodiment of the present invention is the same as that shown in FIG. 1 in that the terminal has an upright structure, but is different from that shown in FIG. 1 in terms of a connecting structure of a cutting mounting parts 61.
In this embodiment, three cutting mounting parts 61 are disposed at both ends of the central connection band 62, respectively, based on the central connection band 62. Among the cutting mounting parts 61 at one end, a short rod-shaped connector 63 is connected at upper ends of second and third cutting mounting parts 61, excluding a first outermost cutting mounting part 61 among the three cutting mounting parts, and the first and second cutting mounting parts 61 are connected at lower ends thereof by a plate-shaped connector 64, thereby forming a structure in which all of the plurality of cutting mounting parts 61 are integrally connected.
A reference number 40, which has not been described yet, indicates an electric wire, a reference number 41, which has not been described yet, indicates a core wire, a reference number 61 a, which has not been described yet, indicates a cutting edge, and a reference number 65, which has not been described yet, indicates a hook protrusion which has the same structure as in the above-described embodiments.
In one embodiment of the present invention, shape deformation preventing portions 65a which prevent deformation of the shape of the hook protrusion due to a load applied to the hook protrusion are formed on the upper surfaces of the connection pieces which correspond to both sides of the hook protrusion 65. The shape deformation preventing portions 65a and an inner surface of an erection piece are mutually inclined, and thus the shape deformation preventing portions 65a and the inner surface of the erection piece mutually form at an obtuse angle.
In addition, a terminal for an electric wire joining connector according to yet another embodiment of the present invention will be described with reference to FIG. 4.
FIG. 4 is a perspective view of yet another embodiment of a terminal for an electric wire joining connector of the electric wire joining connector shown in FIG. 3.
Referring to FIG. 4, the terminal for the electric wire joining connector according to yet another embodiment of the present invention is used to connect two electric wires in a T shape, and the terminal for the electric wire joining connector is a part that electrically connects a first electric wire running in one direction and a second electric wire running in a direction perpendicular to that of the first electric wire.
The T-shaped terminal 70 for the electric wire joining connector has the same structure as tthe embodiment in FIG. 3 in that the terminal 70 for the electric wire joining connector includes a cutting mounting part 71 having a cutting edge 71a, a central connection band 72, connectors 73 and 74, and a hook protrusion 75, but has a different structure from the embodiment in FIG. 3 in that a general shape of the terminal for the electric wire joining connector is a T shape. Accordingly, as a configuration of the terminal 70 is almost the same as that of the terminal 60 shown in FIG 3, a detailed description thereof is omitted.
Although the terminals for the electric wire joining connectors according to the present invention have been shown above to be limited to connecting the two electric wires, electric wires may be connected in a ratio of 1:N or N:M, and the structure of the apparatus may be variously altered.

[Industrial Applicability]

The present invention may be used in the field of connectors used to connect electric wires to each other.

Claims

A terminal for an electric wire joining connector comprising:
a cutting mounting part including erection pieces disposed along a longitudinal direction of an electric wire and having cutting edges which face each other formed thereon and a connection piece which connects lower portions of the erection pieces;

a hook protrusion configured to protrude from an upper surface of the corresponding connection piece between the erection pieces; and

a central connection band configured to connect at least two of the cutting mounting parts to each other.
The terminal for the electric wire joining connector of claim 1, wherein the hook protrusion has a shape that is wider in a lower portion and narrows upward.
The terminal for the electric wire joining connector of claim 1, wherein the hook protrusion has a triangular pyramidal shape with a large width and a narrow thickness.
The terminal for the electric wire joining connector of claim 1, wherein the hook protrusion passes a sheath of the electric wire and is electrically connected to a core wire disposed within the electric wire.
The terminal for the electric wire joining connector of claim 1, further comprising a plurality of connectors which sequentially connect upper end portions and opposite lower end portions of the erection pieces spaced in the longitudinal direction of the electric wire, thereby integrally connecting the erection pieces.
The terminal for the electric wire joining connector of claim 1, wherein a direction of the cutting edge of the cutting mounting part formed on one side of the central connection band and a direction of the cutting edge of the cutting mounting part formed on the other side which faces the one side of the central connection band are parallel to each other.
The terminal for the electric wire joining connector of claim 1, wherein a direction of the cutting edge of the cutting mounting part formed on one side of the central connection band and a direction of the cutting edge of the cutting mounting part formed on the other side which faces the one side of the central connection band are perpendicular to each other.
The terminal for the electric wire joining connector of claim 1, wherein shape deformation preventing portions which prevent deformation of the shape of the hook protrusion due to a load applied to the hook protrusion are formed on the upper surfaces of the connection piece which correspond to both sides of the hook protrusion.
An electric wire joining connector comprising:
a terminal including a cutting mounting part having a plurality of erection pieces disposed along a longitudinal direction of an electric wire and having cutting edges which face each other formed thereon and a connection piece which connects lower portions of the erection pieces, , a hook protrusion protruding from an upper surface of the corresponding connection piece between the erection pieces, and a central connection band which connects at least two cutting mounting parts to each other;

a lower connector in which a space for accommodating the electric wire and the terminal is formed; and

an upper connector coupled to the lower connector and pivoted to provide the electric wire to the terminal.
The electric wire joining connector of claim 9, wherein the hook protrusion has a shape that is wider in a lower portion and narrows upward.
The electric wire joining connector of claim 9, wherein the hook protrusion has a triangular pyramidal shape with a large width and a narrow thickness.
The electric wire joining connector of claim 9, wherein the hook protrusion passes a sheath of the electric wire and is electrically connected to a core wire disposed within the electric wire.
The electric wire joining connector of claim 9, further comprising:
a plurality of connectors which sequentially connect upper end portions and opposite lower end portions of the erection pieces spaced in the longitudinal direction of the electric wire.
The electric wire joining connector of claim 9, wherein a direction of the cutting edge of the cutting mounting part formed on one side of the central connection band and a direction of the cutting edge of the cutting mounting part formed on the other side which faces the one side of the central connection band are formed parallel to each other.
The electric wire joining connector of claim 9, wherein a direction of the cutting edge of the cutting mounting part formed on one side of the central connection band and a direction of the cutting edge of the cutting mounting part formed on the other side which faces the one side of the central connection band are formed perpendicular to each other.