Abstract: Flexible transmission devices, for example for use a tool extensions for effecting rotation of fasteners that are difficult or impossible to access straight on using the normal output of a tool. A series of internal couplers are connected together end-to-end by constrained ball and socket joints that allow tilting between the axes of the couplers while constraining relative rotation of the couplers about said axes. The internal couplers form a flexible shaft inside an outer casing formed by a series of collar-shaped links joined in adjacent pairs by a single-axis pivot connection, each positioned to coincide with a respective one of the ball and socket joints.

Abstract: A rock picker includes a picker grate having a plurality of picker bars extending in a curved path forwardly and downwardly to a forwardmost end for engaging the rocks and lifting them onto the picker grate. A conventional sweeping reel sweeps the rocks to a hopper. The forward end of each of the grate bars includes a portion consisting of a vertical plate parallel to the direction of movement together with a rotating rod which extends across the full width of the picker and is supported by the cup-shaped forward ends of the grate bars. The rod improves the rock picking action and also allows the clearing of trash between the rod and the vertical plate portions exposed at the front of the grate bars. A second embodiment includes a further roe positioned with a trip mechanism forwardly and downwardly of the first rod.