Controllable platform suspension system for treadmill decks and the like and devices therefor

A controllable platform suspension system comprising:

• (a) a treadmill deck;
• (b) a treadmill frame;
• (c) means for allowing movement of said treadmill deck relative to said treadmill frame;
• (b) at least one controllable electromechanical assembly interconnected to said treadmill deck for providing user-controllable impact characteristics including an impact condition of said treadmill deck, wherein said controllable electro-mechanical assembly includes a rotary-acting magnetorheological fluid device.

A controllable platform suspension system for absorbing impacts imparted to a moving member, comprising:

• (a) a platform;
• (b) a frame;
• (c) spring means for flexibly suspending said platform relative to said frame such that said platform is movable in a substantially vertical, downward, bound direction and in a rebound direction relative to said frame;
• (d) at least one controllable fluid device interconnected to said platform for providing user-controllable impact characteristics including a bound direction damping rate, said controllable fluid device operable to provide a plurality of different said bound direction damping rates;
• and
• (e) a controller for controlling said controllable fluid device in response to user input to provide a selected one of said plurality of different said bound direction damping rates.

A controllable platform suspension system for absorbing impacts imparted to a moving member, comprising:

• a platform;
• a frame,
• at least one controllable electro-mechanical assembly interconnected to said platform for providing user-controllable impact characteristics, wherein said controllable electromechanical assembly includes a rotary-acting magnetorheological fluid device, said fluid device further comprising:
• (a) a housing having a recess formed therein,
• (b) means interconnecting said housing to said frame,
• (c) a shaft supported by, yet free to rotate relative to, said housing,
• (d) means interconnecting said shaft to said platform,
• (e) a rotor rotatably secured to said shaft and received within said recess thereby forming at least one gap,
• (f) a magnetorheological fluid contained within said at least one gap,
• (g) magnetic field producing means for producing a magnetic flux when electrically energized, and
• (h) a magnetic circuit for directing said magnetic flux toward said magnetorheological fluid contained within said at least one gap causing an apparent viscosity change of said magnetorheological fluid thereby increasing a vertical restraining force exerted between said frame and said platform.