Structure of rowing machine

Claim 1

A rowing machine comprising a base frame with a front end and a rear end, a flat and elongated seat frame having a front end pivoted to said front end of said base frame and a rear end connected to said rear end of said base frame by a hydraulic cylinder, a sliding seat sliding on said seat frame, first and second handles respectively pivoted to said base frame, two hydraulic cylinders respectively arranged between said first and second handles and said base frame for providing resistance to rowing action; a V-shaped rocker arm having a front end, a middle, and a rear end; two pedals bars arranged on said front end of said rocker arm, and two pedals respectively pivoted to said two pedal bars, wherein said rocker arm is in an arrangement between said base frame and said seat frame for permitting said seat frame to oscillate up and down when said sliding seat is moved back and forth on said seat frame during operation of said rowing machine; said arrangement of said rocker arm including said middle of said rocker arm pivoted to said base frame with said front and rear ends of said rocker arm extending upward, a roller provided on said rear end of said rocker arm, said roller contacting an underside of said seat frame and rolling thereon, and said front end of said rocker art arranged underneath said front of said seat frame.