Abstract: A percussion device 10 which allows beaters 14, 16 to independently and/or simultaneously strike drum 128 by use of a single foot.

Abstract: A chain drive (1), in particular for lifting devices, having a chain (3) which rotates about a chain wheel (2) and whose oval links (6) which are rotated in an alternate manner about 90.degree. interact as vertical and horizontal links with the chain wheel, wherein the horizontal links (6i) are received in pockets (7) of the chain wheel with substantially planar support surfaces (6) and can be supported with their curved ends (6') on teeth (10) which comprise convex flanks (12) and the vertical links (6s) are positioned in a groove (11) between the teeth, wherein the wire cross-section of the chain links (6) is a rectangle having a curvature adjoined thereto towards the inner part of the link and the convex flanks (12) and the planar support surfaces (8) contact each other in a substantially direct manner, i.

Abstract: A data system adapted to accept certain first data associated with a game situation and to forecast future plays in athletic contests. In one embodiment, the data system comprises: a data base containing said first data and further containing second data representing a plurality of probable future plays; a data analyzer adapted to recognize said certain first data and to retrieve said corresponding second data; and a user interface, adapted to accept said certain first data and to display said retrieved second data.

Abstract: An electromagnetically actuate machine balancer including a plurality of peripherally placed magnetic circuits and a power driver which selectively interrupts the magnetic flux through the circuits, thereby moving unbalanced rotors in a desired manner to compensate for machine unbalance.