A treadmill includes a base with two side rails, a frame with two side rods and an endless running belt, two first links, two second links, two third links, a fixing rod which is fixed in-between the two first links with a connection and an actuator is composed of a motor and a motor driven moving part which is pivotally connected to the connection of the fixing rod. Each group of the first links, the second links, the third links and the side rail is structured as a four-bar-link mechanism, which is working to bring up or down the first end of the frame when the actuator is driving the moving part, incline angle of the frame is changing, the purpose of adjusting the inclination of the frame and even folding the frame is simply and efficiently achieved.
A treadmill includes a front leg frame and a connecting arm. The front leg frame has a front end pivoted to a support base. The connecting arm has a lower end pivoted to the leg frame. An upper end of the connecting arm is connected to a threaded sleeve connected telescopically to a motor-driven screw rod disposed at a top side of a tread base. A hydraulic telescopic unit is pivoted to the leg frame and the support base. When the threaded sleeve is driven by the screw rod, the tread base is inclined. When the tread base is folded upward, it is held in position by the hydraulic telescopic unit which is prevented from moving telescopically by engagement with a latch member. The latch member disengages the telescopic unit through a release member provided on the tread base.
