Patent ID: 8069511

Claim:
A gurney comprising: a platform for holding a patient; a frame; first and second X-frame structures each attached between one side of said platform and a corresponding side of said frame to allow said platform to be raised or lowered, each X-frame structure having (a) a first arm pivoted at one end to said frame and being coupled at the other end to a bearing that slides along a first guide rail attached to said platform; and (b) a second arm pivoted at one end to said platform and being coupled at the other end to a bearing that slides along a second guide rail attached to said frame; a motor; a circuit which receives an input voltage for driving the motor; a ball screw threaded shaft driven by said motor; an interior threaded ball nut threadably engaged with said ball screw threaded shaft and mounted in an integrated ball bearing, nut and screw assembly; and a cross-beam that is mechanically coupled to both said integrated bearing, nut and screw assembly and each of said first and second X-frame structures, so as to transmit a rotational motion of said ball screw threaded shaft to sliding motion of said bearings along said first and second guide rails in each of said first and said X-frame structures, wherein a longitudinal axis of the ball screw threaded shaft and said integrated ball bearing, ball and nut assembly pass through an opening through said cross-beam, said opening being symmetrically centered both horizontally and vertically in said cross-beam which is secured to said integrated ball bearing, ball and nut assembly.