US Patent 8176584 Patient-support apparatus with movable top

A patient-support apparatus includes frame and a lift arm. The frame includes a base frame and an upper frame. The lift arm has a first end coupled to the upper frame and a second end spaced apart from the first end and coupled to the base frame. In this embodiment, the lift arm is configured to move the frame in a generally vertical direction while the lift arm rotates with respect to the frame. The apparatus is configured to allow the first end of the lift arm to translate along the upper frame while the second end rotates about an axis that is fixed relative to the base frame. Other embodiments are also disclosed.