Manufacturing method of cylindrical body crimp terminal

1. A manufacturing method of a cylindrical body for processing at least a part of a bend processing portion of a sheet member from an unprocessed shape into a cylindrical shape, the manufacturing method comprising performing in order:

a high bending-rate processing process of bend processing at least a part of the bend processing portion in a width direction at a bending rate higher than a bending rate for plastically deforming the part from the unprocessed shape into the cylindrical shape; and

a shaping process of shaping the bend processing portion processed in the high bending-rate processing process into the cylindrical shape such that each end part of the bend processing portion in a width direction are butted against each other when the bend processing portion is shaped processed into the cylindrical shape, and an inward force occurs in each of the end parts that are abutted against each other,

wherein the bend processing portion that is formed by the high bending rate processing process is formed into a V shape, and

wherein a curvature of a valley formed by the V shape of the V shaped bend processing portion is greater than a curvature of the cylindrical shape.

2. A manufacturing method of a crimp terminal having a cylindrical crimping section, the manufacturing method comprising:

a high bending-rate processing process including

forming a sheet member by a sheet-shaped terminal base material comprising a crimping portion corresponding part which corresponds to the crimping section before a bend processing,

bend processing at least a part of a deformation portion to be plastically deformed into a predetermined bend processing shape in the crimping portion corresponding part, at a bending rate higher than a bending rate of plastically deforming the part from an unprocessed shape into a cylindrical shape, along with the bend processing of at least the crimping portion corresponding part of the terminal base material from the unprocessed shape into the cylindrical shape; and

a shaping process of shaping, after the high bending-rate processing process, the crimping portion corresponding part processed in the high bending-rate processing process into the crimping section of the cylindrical shape, such that each end part of the crimping portion corresponding part in a width direction are butted against each other when the crimping portion corresponding part is shaped processed into the cylindrical shape, and an inward force occurs in each of the end parts that are abutted against each other,

wherein the crimping portion formed by the high bending rate processing process is formed into a V shape, and

wherein a curvature of a valley formed by the V shape of the V shaped crimping portion is greater than a curvature of the cylindrical shape.

3. The manufacturing method of a crimp terminal according to claim 2 , comprising:

setting the deformation portion in a whole of an orthogonal direction orthogonal with a terminal axis direction of the crimping portion corresponding part; and

in the shaping process,

processing the crimping portion corresponding part processed in the high bending-rate processing process by shaping so that an orthogonal cross section orthogonal with a terminal axis direction becomes a circular shape.

4. The manufacturing method of a crimp terminal according to claim 3 , comprising:

setting at least a part of the deformation portion in an intermediate portion in the orthogonal direction of the crimping portion corresponding part; and

in the high bending-rate processing process,

bend processing the intermediate portion at a bending rate higher than a bending rate for plastically deforming the intermediate portion from the unprocessed shape into the predetermined bend processing shape.

5. The manufacturing method of a crimp terminal according to claim 2 , wherein

the terminal base material comprises a transition corresponding part provided continuously to the crimping portion corresponding part at a tip side in a terminal axis direction,

the manufacturing method comprising:

prior to the high bending-rate processing process,

performing an end-part raising process to raise an end part of the crimping portion corresponding part in the width direction and raising the transition corresponding part in a raising direction of the crimping portion corresponding part;

performing a bottom raising process to raise a bottom of the transition corresponding part simultaneously with the end-part raising of the crimping portion corresponding part and the transition corresponding part; and

after the bottom raising process, performing a cylindrical bend processing of a sealing portion corresponding part provided in a portion continuous with the crimping section in the transition corresponding part, together with a cylindrical bend processing of the crimping portion corresponding part.

6. The manufacturing method of a crimp terminal according to claim 5 , further comprising:

performing a process of inserting a core bar into the crimping portion corresponding part after the end parts of the crimping portion corresponding part are abutted with each other, in at least one process out of the high bending-rate processing process and the shaping process; and

performing a process of pressurizing the crimping portion corresponding part in a core-bar inserted state by a pressurizing mold.

7. The manufacturing method of a crimp terminal according to claim 6 , wherein a cross section of the core bar is in a circular shape, and

in the shaping process,

the manufacturing method comprises:

forming a cylindrical crimping section by a process of pressurizing from outside, by a pressurizing mold, the crimping portion corresponding part into which the core bar is inserted.

8. The manufacturing method of a crimp terminal according to claim 5 , wherein the sealing portion corresponding part is formed as a flat-shaped sealing portion by flattening the sealing portion corresponding part in a thickness direction.

9. The manufacturing method of a crimp terminal according to claim 2 , further comprising:

after the shaping process, performing a welding process of welding both ends of the crimping section in a peripheral direction along a terminal axis direction by a high-energy density heat source.

10. The manufacturing method of a crimp terminal according to claim 1 , further comprising:

after the shaping process, performing a welding process of welding both ends of the bend processing portion in a peripheral direction along a terminal axis direction by a high-energy density heat source.

11. A manufacturing method of a crimp terminal having a cylindrical crimping section, the manufacturing method comprising:

a high bending-rate processing process including

forming a sheet member by a sheet-shaped terminal base material comprising a crimping portion corresponding part which corresponds to the crimping section before a bend processing,

bend processing at least a part of a deformation portion to be plastically deformed into a predetermined bend processing shape in the crimping portion corresponding part, at a bending rate higher than a bending rate of plastically deforming the part from an unprocessed shape into a cylindrical shape, along with the bend processing of at least the crimping portion corresponding part of the terminal base material from the unprocessed shape into the cylindrical shape;

a shaping process of shaping, after the high bending-rate processing process, the crimping portion corresponding part processed in the high bending-rate processing process into the crimping section of the cylindrical shape such that each end part of the crimping portion corresponding part in a width direction are butted against each other when the crimping portion corresponding part is shaped processed into the cylindrical shape, and an inward force occurs in each of the end parts that are abutted against each other;

inserting into the crimping section a conductor tip having an insulating cover peeled off at least at a tip side of an insulated wire which covers a conductor with the insulating cover; and

crimping the crimping section,

wherein the crimping portion formed by the high bending rate processing process is formed into a V shape, and

wherein a curvature of a valley formed by the V shape of the V shaped crimping portion is greater than a curvature of the cylindrical shape.