Abstract: A drive mechanism includes a drive shaft and a sprocket drive assembly. The sprocket drive assembly includes a hub mechanically coupled to the drive shaft, a first side support secured to the hub, a second side support secured to the hub, and a plurality of engagement members each interposed between the first side support and the second side support. Each of the plurality of engagement members is rotatably secured to each of the first side support and the second side support. The drive mechanism further includes a track assembly which has a plurality of shoes which are secured to one another to form a track, and a plurality of drive lugs which are mounted to the plurality of shoes. Each of the plurality of drive lugs has a first grasping notch and a second grasping notch defined therein. The plurality of drive lugs includes a first drive lug and a second drive lug which are adjacent to each other.

Abstract: An opening/closing mechanism for use in a circular-arc shaped sliding door including a transverse frame having a circular-arc horizontal sectional shape and mounted on the upper parts of a pair of left and right door bodies; a drive pulley and a driven pulley mounted on the circumferentially one end of the transverse frame and on the other end thereof, respectively; and an endless belt wound between and around the drive pulley and a driven pulley, the pair of door bodies being connected in place to the endless belt so that they may be slidably moved in opposite directions to each other along a pair of left and right guide rails, respectively, each of which is bent in a circular-arc shape concentric with the center of the circular-arc of the transverse door frame.

Abstract: An endless standard link chain closed with a quarter- or half-turn twist to increase the contact length by a factor of four or two, respectively, and thus extend its life when used on power drives utilizing sprockets capable of engaging standard link chains.

Abstract: Endless power transmission belts of spliceless, Mobius strip construction comprising a continuous strength member embedded in an elastomeric material, together with methods for the manufacture of such belts, are provided.