Exercise device

An exercise device, comprising:

• a frame;
• two first swing arms respectively arranged at a left side and a right side of the frame, each first swing arm having a first end pivotally coupling with the frame;
• two second swing arms coupling with the two first swing arms, each first swing arm having a second end pivotally coupling with a first end of one corresponded second swing arm;
• two pedals coupling with the two second swing arms, each second swing arm having a second end coupling with one corresponded pedal;
• a resistance device having an axle pivoted to the frame for providing a resistance;
• two cranks respectively arranged at a left side and a right side of the resistance device, each crank having a first end coupling with the axle of the resistance device;
• two link rods coupling with the two cranks and the two second swing arms, each link rod having a first end and a second end, the first end of each link rod pivotally coupling with a second end of one corresponded crank, the second end of each link rod pivotally coupling with a portion of one corresponded second swing arm;
• a lever bracket having two fulcrums and pivotally coupling with the frame via two first pivots;
• two rock rods coupling with the lever bracket and the two second swing arms, each rock rod having a first end pivotally coupling with one corresponded fulcrum and a second end pivotally coupling with a portion of one corresponded second swing arm;
• and
• an adjusting device being arranged between the frame and the lever bracket and movably coupling with the lever bracket, so as to adjust a distance between the axle of the resistance device and the two fulcrums of the lever bracket, wherein the adjusting device comprises a motor, a screw, and a tube, the tube is internally thread to engage with the screw, and the motor is used to drive the screw to rotate, so that the tube is moved along the screw in a direction toward the motor or away from the motor, and wherein the adjusting device movably couples to the lever bracket via a linkage, in which the tube of the adjusting device couples with a portion of the linkage, a first end of the linkage pivotally couples with a second pivot of the lever bracket, and a second end of the linkage pivotally couples with a pivot of a supporting structure of the frame.