Abstract: An engagement chain includes a pair of first and second chain members that are engaged so as to be integrated with each other by moving in an advancing direction and disengaged from each other so as to bifurcate by moving in a retreating direction from the integrated engaged state. A first link plate of the first chain member includes first and second pin holes through which a coupling pin is inserted. A second link plate of the second chain member includes first and second pin holes through which a coupling pin is inserted. A first distance between the first and second pin holes of the first link plate is shorter than a second distance between the first and second pin holes of the second link plate.

Abstract: An interlocking chain unit includes a stepped rod that determines the positions of case plates in a pair and those of guide plates relative to each other. The stepped rod has a small-diameter part that passes through passage holes of the guide plates respectively. The stepped rod has opposite end portions fitting in countersunk holes respectively formed in respective inner surfaces of the case plates. The stepped rod has a large-diameter part with a guide plate side step abutting on a rim of the passage hole of the guide plate, and a case plate side step abutting on a rim of the countersunk hole of the case plate.

Abstract: An interlocking chain unit includes a stepped rod that determines the positions of case plates in a pair and those of guide plates relative to each other. The stepped rod has a small-diameter part that passes through passage holes of the guide plates respectively. The stepped rod has opposite end portions fitting in countersunk holes respectively formed in respective inner surfaces of the case plates. The stepped rod has a large-diameter part with a guide plate side step abutting on a rim of the passage hole of the guide plate, and a case plate side step abutting on a rim of the countersunk hole of the case plate.