This is a torque-transmitting device which I invented while on a visit
to Ned Thomas's materials lab at MIT in the Spring of 1995.  Ned had
shown me some sheets of an elastic polymer material reinforced in one
direction with high tensile fibers.  I showed them this novel application
of their material.

Unlike a rigid screw shaft, the utility of this device is that it
transmits torque in only one direction; that is, it is rigid for one
direction(say, clockwise) torque, but flaccid for the opposite
(counter-clockwise) torque.  The key idea is a diagonal lamination
process creating helical fibers in the elastic polymer sheets when
rolled to form the cylindrical shaft of the one way screw; of course
the same idea works in other materials as well, and the process need
not invlove rolling up of flat sheets.  Since these fibers have high
tensile strength, they will be rigid for a clockwise torque when the
helices are left-handed (and vice versa).

This invention is subject to a non-disclosure agreement with the folks
at MIT.  For more information, please contact me or Ned Thomas.