Patent ID: 7329209

Claim:
A treadmill comprises: a base having two side rails, each of the two side rails having a first pivotal point and a second pivotal point; a frame having two side rods; each of the two side rods having a pivotal point on the first end; an endless running belt is mounted on the frame; two first links, each of the first links having a first pivotal point, a second pivotal point and a third pivotal point, the third pivotal point respectively pivotally connected to the pivotal point on the each of the two side rods of the frame; two second links, the first end of each of the two second links respectively pivotally connected to the first pivotal point of each of the two side rails of the base, the second end of each of the two second links respectively pivotally connected to the first pivotal point of each of the two first links; two third links, the first end of each of the two third links respectively pivotally connected to the second pivotal point of each of the two side rails of the base, the second end of the two third links respectively pivotally connected to the second pivotal point of each of the two first links; a fixing rod fixed in-between the two first links and having a connection; and an actuator comprising a motor and a motor driven moving part which is pivotally connected to the connection of the fixing rod.