Patent ID: 7913343

Claim:
A ramp assembly, comprising: (a) a ramp portion configured for reciprocating motion between a stowed position, a deployed position, and a neutral position; and (b) a counterbalance associated with the ramp portion, comprising: (i) a first shaft configured to rotate (1) in a first direction when the ramp portion moves toward the stowed position, and (2) in a second direction opposite the first direction when the ramp portion moves toward the deployed position; (ii) a crank fixedly coupled to the shaft; (iii) a rod rotatably coupled to the crank about a first axis of rotation, the first axis of rotation moving along an arcuate path when the ramp portion reciprocates between the stowed position and the deployed position; (iv) an end fitting coupled to the rod; (v) an end stop slidably coupled to the rod; and (vi) a compression spring disposed between the end fitting and the end stop, wherein the compression spring provides a force to bias the ramp portion (1) toward the stowed position when the ramp portion is between the deployed position and the neutral position, and (2) toward the deployed position when the ramp portion is between the stowed position and the neutral position.