Patent ID: 7113371

Claim:
A head stack assembly for a disk drive having a disk, the head stack assembly comprising: a body portion; an actuator arm cantilevered from the body portion; a hinge, a first surface of the hinge being coupled to the actuator arm; a load beam having a first end and a second end, the first end including a load beam surface that faces and contacts a second surface of the hinge, the second surface facing away from the first surface; a gimbal coupled to the second end of the load beam, and a slider coupled to the gimbal; wherein the first surface includes a first convex portion defining a first radius of curvature, adjacent the actuator arm, and adjacent a first concave portion of the first surface, defining a second radius of curvature, adjacent, a second convex portion of the first surface, defining a third radius of curvature, adjacent a second concave portion of the first surface, adjacent the first end.