Patent ID: 6017040
Filing Date: 2000-01-25
Classification: B62B

Abstract:
A platform arrangement wherein the platform is supported on a support mechanism, including a scissors jack arrangement comprising two spaced apart pairs of pivotally connected first and second lever arms, a balance beam extending between said spaced apart pairs of lever arms, and a biasing element, the first arm of one of said pairs of lever arms being connected directly to one end of said balance beam and the second arm of the other of said pairs of lever arms being connected to the other end of the balance beam via said biasing element so that a leverage effect is applied at both ends of the balance beam, the support mechanism being arranged to urge the platform upwardly towards a first working position whilst permitting downward movement of the platform when a load is placed on the platform, the amount of downward movement being dependent upon the load, wherein changes in the degree of biasing provide for incremental movements of the platform, in response to increasing loads placed thereon, wherein the load/tension ratio of the biasing element may be adjusted to allow the platform to react differently to different densities of load, and wherein the balance beam member is supported for rotation about a fulcrum, the position of the fulcrum determining the load applied to the biasing element and hence the sensitivity of the biasing element, and enabling an adjustable pre-load to be applied to the biasing element.