Abstract: Link-type chain assemblies are disclosed comprising alternating, laterally spaced pairs of inner and outer link plates having overlapping ends pivotally interconnected by rollers between the inner link plates at the overlapping ends. Mounting flanges extend axially outwardly from each of the inner and outer link plates, and plate members are mounted on the mounting plates to maintain the roller axes generally coplanar and to preclude pivotal displacement of adjacent pairs of inner and outer link plates about the roller axes in at least one direction. In one chain assembly, the plate members mounted on the mounting flanges span adjacent pairs of inner and outer link plates to preclude pivotal displacement of the spanned pair of link plates in opposite directions about the roller axis therebetween.

Abstract: A rigid drive assembly for a telescoping mast is comprised of a pair of flexible link chains disposed at right angles to one another with respect to the pivot axes of the chain links and provided with interengaging latching elements which rigidly interconnect the two chains for movement along a linear path to extend and retract the mast. The two chains are spaced apart, and the latching elements interengage in the space between the two chains and include a plurality of latching plates on one of the chains extending transversely of the path and having openings therethrough in the direction of the path, and a pair of driving latch members for each latch plate engaging opposite sides of the latch plate and having a finger extending into the opening thereof.