US Patent 7261676 Exerciser having improved resistive device

An exerciser includes a shaft rotatably disposed on a base, a housing rotatably engaged on the shaft and having a chamber formed by an outer peripheral wall which has a groove, a belt wound around the tube for rotating the housing, a barrel received in the chamber of the housing and secured to the shaft and having a slot. A coil spring is received in the housing and has two ends engaged into the slot of the barrel and the groove of the outer peripheral wall of the housing. A cover includes a space formed by an outer peripheral fence, to suitably enclose the chamber of the housing.