Precessional exercising device

A precessional exercising device adapted to be attached to a limb of an individual, comprising:

• a housing containing a rotatable cup-shaped mass,
• said mass having a spin axis about which the mass is dynamically balanced so that the centroid of mass of said mass lies on said spin axis,
• said mass having a peripheral lip with a cylindrical inner surface surrounding and coaxial with said spin axis,
• said housing also having top and bottom holding surfaces which are substantially perpendicular to said spin axis and equidistant from the centroid of mass of said mass;
• means for visually differentiating said top and bottom surfaces from each other;
• a shaft disposed within said housing on said housing on said spin axis;
• first and second bearings disposed within said housing and spaced apart along said spin axis for rotatably supporting said shaft for rotation about said spin axis,
• said mass being secured to said shaft at a point between said bearings;
• an electric motor for spinning the mass about said spin axis,
• said motor having a stator core and a stator winding disposed on said core,
• said stator winding being disposed within the lip of said mass,
• said motor having a rotor comprising said mass, said rotor including a plurality of permanent magnets disposed on and secured to the cylindrical inner surface of said lip and surrounding the stator winding of said stator, so that when said stator winding is energized to generate a rotating magnetic field which interacts with the magnetic fields of said permanent magnets, said mass is caused to rotate at a speed corresponding to the speed of rotation of the stator magnetic field;
• and
• holding means for enabling said housing to be rotated so as to change the direction of said spin axis,
• said holding means comprising grip means connected to said housing, extending adjacent at least one of said top and bottom holding surfaces, and adapted to retain a limb extremity of an individual in a position with a selected one of said holding surfaces adjacent a surface of said extremity and said spin axis substantially perpendicular to said extremity surface, so that the centroid of mass of said rotating mass is displaced from the surface of said limb extremity in a direction substantially perpendicular thereto.