Connection structure for terminal fitting

1. A connection structure for a terminal fitting comprising:

the terminal fitting including a terminal body and a plurality of terminal connection portions extending from the terminal body; and

connection terminals connected to electric wires,

wherein each of the connection terminals include a pair of fastening caulking pieces,

wherein the pair of fastening caulking pieces are caulked with opposite side portions of a corresponding one of the terminal connection portions from outside so as to roll up the opposite side portions so that the connection terminal is caulked and fastened to the terminal fitting,

wherein the terminal connection portion and the connection terminal include an engagement mechanism that prevents the terminal connection portion from detaching from the fastening caulking pieces, and

wherein the terminal fitting is connected to the electric wires through the connection terminals.

2. The connection structure for the terminal fitting according to claim 1 ,

wherein the engagement mechanism includes concave-convex engagement portions respectively provided in opposed surfaces in which the terminal connection portion and the connection terminal abut against each other.

3. The connection structure for the terminal fitting according to claim 1 ,

wherein the engagement mechanism includes electric-wire-side side faces of the fastening caulking pieces and engagement protruding portions provided in the terminal connection portions so as to abut against the electric-wire-side side faces.

4. The connection structure for the terminal fitting according to claim 1 ,

wherein the engagement mechanism includes engagement protruding portions that are formed in the fastening caulking pieces and engagement concave portions that are formed in fastened caulking pieces erecting on opposite side portions of the terminal connection portions so as to be engaged with the engagement concave portions.