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

DETAILED DESCRIPTION The present invention is a controllable suspension system for a platform, which is particularly useful in a treadmill exercise apparatus for producing a variable "feel" characteristic of the treadmill deck contacted by the treadmill user.
This deck "feel" can be adjusted by the user or through an appropriate computer program, manual selection, or the like to change the bound (vertical downward) rate (impact spring rate or damping rate) of the deck of the treadmill as the user impacts the deck with his/her foot.
In this way, the user can adjust the "feel" of the deck to simulate various running surfaces, for example running on pavement, rubber track, gravel, grass, sand, etc.
or more generally, to provide a deck which has various and selectable response to impact forces exerted thereon.
In a broader sense, the damping and/or stiffness of the MR devices supporting the deck platform can be adjusted, thereby proving the means for controlling impact conditions of whatever is coming into contact with the deck platform.
The means for providing control of impact conditions comprises an controllable electro-mechanical device.
In another aspect, devices and means are described herein whereby controllable forces can be achieved in one direction and uncontrollable, and relatively free return (rebound), may be provided in the other direction without having to "rapidly switch" between a high and low damping state as in prior art MR devices.
It is an advantage of one aspect of the present invention controllable suspension system that variable forces restraining impact can be obtained, thereby providing a variable impact "feel" continuously ranging from a "soft" condition to "hard" condition.
It is an advantage of the controllable platform suspension system of the present invention that the impact force condition produced can be easily and quickly adjusted by the user, i.
e.
, it is "user selectable" or it may be controlled by a digital controller, computer, or microprocessor to follow a preselected regimen