Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
342 words
A lift comprising: a platform having a top side on which an article to be lifted rests and an underside; and a scissors jack attached below the platform and comprising a shaft disposed at the underside of the platform and having two chain wheels rotationally fixed thereto, means connected to the platform for guiding the shaft for movement along one direction parallel to the underside of the platform, a first pair of parallel scissoring legs having one end of each articulated with the platform, a second pair of parallel scissoring legs havine one end of each attached to the shaft and wherein the first and second pairs of legs are connected at scissoring axes intermediate of each of the first and second pairs of legs, a transverse beam, means fixed to the underside of the platform and connected to the transverse beam for moving the transverse beam parallel to the underside of the platform along said one direction and towards and away from the shaft, a pair of auxiliary rails connected at one end to the shaft and at an intermediate point to the scissoring axes, a cross-head connecting the free ends of the pair of auxiliary rails, a pair of guide rails connected at one end to the scissoring axes, wherein the pairs of auxiliary rails and guide rails have curved portions and form a wedge-shaped gap with an open side that faces away from the scissoring axes, and the pairs of auxiliary rails and guide rails are about half as long from the scissoring axes to their free ends as the free ends of the first and second pairs of scissoring legs to the scissoring axes, an axle disposed parallel with the shaft and having two independently rotating rollers mounted on each end thereof and resting against one auxiliary rail and one guide rail at the curved portions thereof and two chains connected at one end to the axle and which extend around the chain wheels on the shaft and are connected at the other end to the transverse beam.
Claim 2
Dependent Claim
342 words
A lift comprising: a platform having a top side on which an article to be lifted rests and an underside; and a scissors jack attached below the platform and comprising a shaft disposed at the underside of the platform and having two chain wheels rotationally fixed thereto, means connected to the platform for guiding the shaft for movement along one direction parallel to the underside of the platform, a first pair of parallel scissoring legs having one end of each articulated with the platform, a second pair of parallel scissoring legs havine one end of each attached to the shaft and wherein the first and second pairs of legs are connected at scissoring axes intermediate of each of the first and second pairs of legs, a transverse beam, means fixed to the underside of the platform and connected to the transverse beam for moving the transverse beam parallel to the underside of the platform along said one direction and towards and away from the shaft, a pair of auxiliary rails connected at one end to the shaft and at an intermediate point to the scissoring axes, a cross-head connecting the free ends of the pair of auxiliary rails, a pair of guide rails connected at one end to the scissoring axes, wherein the pairs of auxiliary rails and guide rails have curved portions and form a wedge-shaped gap with an open side that faces away from the scissoring axes, and the pairs of auxiliary rails and guide rails are about half as long from the scissoring axes to their free ends as the free ends of the first and second pairs of scissoring legs to the scissoring axes, an axle disposed parallel with the shaft and having two independently rotating rollers mounted on each end thereof and resting against one auxiliary rail and one guide rail at the curved portions thereof and two chains connected at one end to the axle and which extend around the chain wheels on the shaft and are connected at the other end to the transverse beam.
Claim 3
Dependent Claim
35 words
The lift as in claim 1, wherein portions of the first and second pairs of scissoring legs that extend towards their free ends are shorter than portions connected to the platform or to the shaft.
Claim 4
Dependent Claim
23 words
The lift as in claim 1, further comprising transport rollers at the free ends of the first and second pairs of scissoring legs.
Claim 5
Dependent Claim
34 words
The lift as in claim 1, wherein the means for moving the transverse beam comprises a tensioning device consisting of a hydraulic cylinder with a piston rod to which the transverse beam is attached.