Connection structure and connection method
A connection structure includes: a first wire; a second wire having a diameter smaller than a diameter of the first wire; a connection member configured to connect the first wire and the second wire, wherein a distal end portion of the first wire is inserted from an opening portion at one end of the connection member to be crimped, and a proximal end portion of the second wire is inserted from an opening portion at another end of the connection member to be crimped, the opening portion at the other end having a diameter smaller than a diameter of the opening portion at the one end.
1. A method of manufacturing a connection structure, the method comprising:
inserting a distal end portion of a first wire into a first opening at a first end of a connection member to be crimped;
reducing a diameter of a hollow portion including a second opening at a second end of the connection member; and
after reducing the diameter of the hollow portion including the second opening at the second end of the connection member, inserting a proximal end portion of a second wire into the second opening at the second end of the connection member to be crimped, the second wire having a diameter smaller than a diameter of the first wire.
2. The method according to claim 1 , wherein:
the proximal end portion of the second wire that is inserted into the second opening is formed by two ends of the second wire that are bundled, and a portion of the second wire between the two ends forms a snare having a loop shape; and
the first wire is configured to function as an operation wire operable to pull the snare.
3. The method according to claim 1 , wherein a diameter of the proximal end portion is smaller than a diameter of the first wire.
4. The method according to claim 1 , wherein reducing the diameter of the hollow portion is performed after the distal end of the first wire is inserted into the first opening.
5. A method of manufacturing a connection structure, the method comprising:
inserting a distal end portion of a first wire into a first portion of a connection member through a first opening in a first end of the connection member;
crimping the first portion of the connection member to the distal end portion of the first wire inserted therein;
after crimping the first portion of the connection member, reducing a diameter of a second portion of the connection member, the second portion having a second opening in a second end of the connection member;
after reducing the diameter of the second portion of the connection member, inserting a proximal end portion of a second wire into the second portion through a second opening in a second end of the connection member, the second wire having a diameter smaller than a diameter of the first wire; and
crimping the second portion of the connection member to the proximal end portion of the second wire inserted therein.
6. The method according to claim 5 , wherein:
the proximal end portion of the second wire that is inserted into the second opening is formed by two ends of the second wire that are bundled, and a portion of the second wire between the two ends forms a snare having a loop shape; and
the first wire is configured to function as an operation wire operable to pull the snare.
7. The method according to claim 5 , wherein a diameter of the proximal end portion is smaller than a diameter of the first wire.