| 摘要 |
PROBLEM TO BE SOLVED: To make it hard to cause damage such as a scratch or the like on a metal plate when folding back the metal plate for producing one pair of flange parts, to allow adoption of a plate material lighter than a conventional one and to promote improvement in degree of freedom of design for obtaining a yoke lighter than the conventional one though equal to that in strength.SOLUTION: One pair of recessed grooves 27, 27 are formed in parts situated inside in relation to a folding back direction for respectively configuring the both flange parts at two positions close to both ends in a length direction of a proximal end side plate part 20a of an intermediate stock, across the full width of the proximal end side plate part 20a. Then, the parts close to the both ends in the length direction of the proximal end side plate part 20a are folded back along the both recessed grooves 27, 27 to serve as the both flange parts. |
