Four-corner balance mechanism of servo actuator

The invention belongs to the technical field of fluid pressure actuating mechanisms in mechanical engineering, and particularly relates to a four-corner balance mechanism of a servo actuator, which comprises a piston cylinder, an axial through piston hole is formed in the piston cylinder, a piston rod is movably connected in the piston hole, and the outer end of the piston rod is connected with a fisheye joint; the fisheye connector comprises a connecting rod and a circular ring part fixedly connected to the outer end of the connecting rod. The outer side of the piston cylinder is connected with a balance shaft, the balance shaft is perpendicular to the piston rod, and the balance shaft is sleeved with a sliding sleeve in the axial direction in a sliding mode; a supporting rod is connected between the sliding sleeve and the connecting rod, one end of the supporting rod is pivotally connected with the connecting rod through a first pivotal shaft, and the other end of the supporting rod is pivotally connected w