Hydraulic exerciser

Claim 1

In a hydraulic exerciser including a cylinder in which the working fluid is received, a piston slidable in said cylinder and attached to a rod which extends outwardly from one end of said cylinder and which is provided with securing means on the end thereof, a fluid reservoir concentrically disposed around said cylinder and in fluid communication therewith, and a bearing member mounted to one end of said cylinder and slidably receiving said rod passed therethrough, said bearing member provided with a first duct in fluid communication with the cylinder and a second duct in fluid communication with the fluid reservoir to pass working fluid therebetween by movement of the piston within the cylinder, the resistance offered when a quantity of working fluid flows through the ducts resulting in an opposite force against a force exerted on the rod, the improvement comprising a controlling ring member mounted above said bearing member having inner and outer ring portions having upper surfaces at different levels and including a radial extension extended across said inner and outer ring portions and defining a first end and a second end of a vertical wall interconnecting the inner and outer ring portions the radius of said interconnecting wall varying from said first end of said vertical wall to said second end of said vertical wall; and a bushing member disposed above said controlling ring member which is provided with a fluid passageway having an opening facing said vertical wall and which is capable of being turned with respect to said controlling ring member so that the area of said opening closed off by the uppermost surface of the ring portions can be varied, to control the flow of working fluid through said fluid passageway.