摘要 |
A yoke lever includes an upper wall and two side walls. The upper wall includes an elongated hole, and the side wall includes a pivot coupled portion. A secondary lever includes an insertion coupling portion to be inserted and coupled to the elongated hole from the upper side. The insertion coupling portion includes an insertion tube portion having two opposing side walls, which face the inner surfaces of the side wall of the yoke lever, and two end walls, which connect the longitudinal ends of the opposing side walls. A pivot coupling portion projects from a longitudinally central portion of the opposing side wall to engage the pivot coupled portion while permitting pivoting. |