Patent ID: 7318609

Claim:
A chuck assembly comprising: a first member; a second member; and a chuck comprising: an annular ring portion into which at least said first member is inserted; a first engaging portion which extends from said annular ring portion along a central axis of said annular ring portion and which engages with said first member; a second engaging portion which extends from said annular ring portion along said central axis of said annular ring portion and which elastically engages with a recess of said second member; and a three-dimensionally shaped portion on an end of said second engaging portion, said three-dimensionally shaped portion including a pair of plastically deformed expanded portions formed by plastically deforming a metal plate, and wherein a bent and folded intermediate portion defining a crease is formed between said pair of plastically deformed expanded portions, so that respective concavities of said pair of plastically deformed expanded portions face each other.