Terminal-equipped electric wire, terminal crimping apparatus, and method of manufacturing terminal-equipped electric wire

1. A terminal-equipped electric wire comprising:

an electric wire having a core wire bare at an end thereof; and

a crimp terminal physically and electrically connected to the core wire by being crimped to the end of the electric wire, wherein

the crimp terminal includes an electric wire connection portion in which a pair of barrel pieces is wound around the end of the electric wire placed on a bottom thereof to overlap each other,

the electric wire connection portion includes a core wire crimping portion in which the bottom and the pair of barrel pieces are crimped to the core wire at the end of the electric wire, and a sheath crimping portion in which the bottom and the pair of barrel pieces are crimped to a sheath at the end of the electric wire,

the electric wire connection portion is crimped to the end of the electric wire in a state where a distance between the bottom and the pair of barrel pieces in a sandwiching direction of the sheath in the sheath crimping portion is wider than a distance between the bottom and the pair of barrel pieces in a sandwiching direction of the core wire in the core wire crimping portion,

the core wire crimping portion includes a first core wire crimping portion crimped to a distal end side of the core wire, and a second core wire crimping portion, in which the pair of barrel pieces is wound around the core wire while widening the distance with respect to the bottom in the sandwiching direction of the core wire as being directed from the first core wire crimping portion side to the sheath crimping portion side, between the first core wire crimping portion and the sheath crimping portion,

the core wire crimping portion and the sheath crimping portion have an overlapping area in which one of the barrel pieces and the other barrel piece overlap each other,

a boundary crimping area arranged at a boundary part between the second core wire crimping portion and the sheath crimping portion includes a plurality of coupling crimping portions, which connect two crimping portions having different angles with respect to a drawing direction of the electric wire from the crimp terminal between the second core wire crimping portion side and the sheath crimping portion side, in at least the overlapping area, and

the pair of barrel pieces are together bending convexly toward outside at each coupling crimping portion.

2. The terminal-equipped electric wire according to claim 1 , wherein

the coupling crimping portion is formed in an arc shape that is gradually changed from the one of the crimping portions to the other crimping portion.

3. The terminal-equipped electric wire according to claim 1 , wherein

in each coupling crimping portion, an inner surface of one of the barrel pieces disposed inside with respect to the other of the barrel pieces bends convexly toward outside in the overlapping area.

4. The terminal-equipped electric wire according to claim 1 , wherein,

the coupling crimping portion closest to the sheath crimping portion among the plurality of coupling crimping portion is disposed at the end edge of the sheath.

5. A terminal crimping apparatus comprising:

a first mold that supports a bottom of a crimp terminal having the bottom and a pair of barrel pieces with a support surface; and

a second mold that winds the pair of barrel pieces around an end of an electric wire to overlap each other while shortening a distance with respect to the first mold in a state where the end of the electric wire is inserted into a space surrounded by the bottom and the pair of barrel pieces, wherein

the second mold includes a core wire pressing portion that crimps the pair of barrel pieces to a core wire bare at the end of the electric wire, and a sheath pressing portion that crimps the pair of barrel pieces to a sheath at the end of the electric wire,

the core wire pressing portion and the sheath pressing portion are arranged such that a distance between the core pressing portion and the support surface in a relative movement direction between the first mold and the second mold is narrower than a distance between the sheath pressing portion and the support surface in the relative movement direction,

the core wire pressing portion includes a first core wire pressing portion that crimps the pair of barrel pieces to a distal end side of the core wire; and a second core wire pressing portion that crimps the pair of barrel pieces to the core wire while widening a distance between the bottom and the pair of barrel pieces in a sandwiching direction of the core wire as being directed from the first core wire pressing portion side to the sheath pressing portion side, between the first core wire pressing portion and the sheath pressing portion,

the core wire pressing portion and the sheath pressing portion have a joining pressing area to form an overlapping area in which one of the barrel pieces and the other barrel piece overlap each other, and

a boundary pressing area arranged at a boundary part between the second core wire pressing portion and the sheath pressing portion includes a plurality of coupling pressing portions, which connect two pressing portions having different angles with respect to a drawing direction of the electric wire from the crimp terminal between the second core pressing portion side and the sheath pressing portion side, in at least the joining pressing area.

6. A method of manufacturing a terminal-equipped electric wire, the method comprising:

a terminal support step of supporting a bottom of a crimp terminal having the bottom and a pair of barrel pieces with a support surface of a first mold; and

a crimping step of winding the pair of barrel pieces around an end of an electric wire to overlap each other while shortening a distance between the first mold and a second mold in a state where the end of the electric wire is inserted into a space surrounded by the bottom and the pair of barrel pieces to form a core wire crimping portion crimped to the core wire bare at the end of the electric wire and a sheath crimping portion crimped to a sheath at the end of the electric wire, wherein

in the crimping step, the pair of barrel pieces is crimped to a distal end side of the core wire at the end of the electric wire by a first core wire pressing portion of the second mold arranged to oppose the support surface, the pair of barrel pieces is crimped to the sheath at the end of the electric wire by a sheath pressing portion of the second mold arranged to oppose the support surface, and the pair of barrel pieces is crimped to the core wire while widening a distance between the bottom and the pair of barrel pieces in a sandwiching direction of the core wire as being directed from the first core wire pressing portion side to the sheath pressing portion side by a second core wire pressing portion of the second mold arranged to oppose the support surface between the first core wire pressing portion and the sheath pressing portion, thereby forming an overlapping area in which one of the barrel pieces and the other barrel piece overlap each other, and

in the crimping step, the pair of barrel pieces is crimped to the end of the electric wire by a plurality of pressing portions, provided in at least a joining pressing area to form the overlapping area in a boundary pressing area arranged at a boundary part between the second core wire pressing portion and the sheath pressing portion, that is, coupling pressing portions, which connect two pressing portions having different angles with respect to a drawing direction of the electric wire from the crimp terminal between the second core wire pressing portion side and the sheath pressing portion side, when crimping the pair of barrel pieces by the first core wire pressing portion, the sheath pressing portion, and the second core wire pressing portion.