| 摘要 |
<p>A linkage assembly (20) for use with a platform or step lift (22) for transmitting force from a linear actuator (228) to a barrier plate (102) pivotally attached to the outer edge of the platform (26) of the lift so as to cause the barrier plate to travel through a rotational path of at least 180 degrees. The linkage assembly is designed so that no portion thereof extends more than about 0.25 inch above the upper surface (28) of the barrier plate and the top surface (48) of the platform, and so that the barrier plate is driven downwardly toward the extended position with a force insufficient to cause serious injury to a person's feet positioned in the path of travel of the barrier plate. Additionaly, a hinge structure (700) is provided for use with a step lift for coupling the platform with its vertical extensions (66, 68) so as to permit the latter to pivot relative to the platform as the extensions move up and down within the vertical guides (80, 82) in which the vertical extensions are slidably received. The linkage assembly (20) and horizontally oriented linear actuator (228) enable movement of a barrier plate (102) between a retracted position and a barrier position while the step/platform assembly (24) is in the step position. A hinge (800) that connects the barrier plate (102) to an outer platform member (103) is provided with at least one laterally extending projection (810). When the step/platform assembly (24) is in the step position, and the barrier plate (102) is moved to the retracted position, the projection (810) on the hinge (800) engages a slot (114) formed in the top of one of a pair of rails (108) that support the step/platform assembly (24), thereby latching the step/platform assembly (24) in the stowed position. When it is desired to extend the step/platform assembly (24) into the platform position, the barrier plate (102) is raised to the barrier position, thereby disengaging the projection (810) from the slot (114) in the rail (108). The linear actuator (228) is mounted to support plates (600) attached to the bottom surface (30) of the outer platform member (103) such that the linear actuator (228) is in a substantially horizontal orientation at all times.</p> |
