Linking structure having metal pin interposed between metal link and metal lever

A linking structure (20) enables a metal lever (21) and a metal link (22) to be linked via a metal pin (linking pin) (23). The metal lever (21) has a circular linking hole (21a). The metal pin (23) has a support shaft part (23a) that can rotate in the linking hole (21a) while being insertable in the linking hole (21a) and can move a set amount in the axial direction, a head part (23b) formed at one end of the support shaft part (23a), and a linking shaft part (23c) formed at the other end of the support shaft part (23a). The metal link (22) has a joining hole (22a) in which the support shaft part (23a) is engaged, and the metal link (22) is linked integrally with the metal pin (23). At least one end part in the axial direction of the support shaft part (23a) of the metal pin (23) is provided with a permitting part (spherical surface (23a1)) for maximizing the amount of axial oscillation of the metal lever (21) relative to the metal pin (23). The linking structure for linking the metal lever (outside open lever (21)) and the metal link (open link (22)) thereby facilitates assembly.