Apparatus for lifting an elongate member
US4730742A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 29, 1986 |
| Grant date | Mar 15, 1988 |
| Priority date | — |
| Expiry date | Dec 29, 2006 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB66F19/00
- WIPO fieldHandling
- WIPO sectorMechanical engineering
Abstract
An apparatus for supportably elevating and lowering material handling apparatus having an elongate member includes two arms radiating upwardly from a base. A lower undercarriage arm is pivotably attached to the elongate member, and the lift arm is attached to a roller support which moves along a rail on the elongate member. The roller support and attached lift arm arm moved by a winch-drawn cable. At least one pair of spaced support sheaves is mounted on the elongate member, and the cable passes under the sheaves. At least one riser post extends upwardly from the base and is attached to the lower undercarriage arm so that it intersects the cable between the spaced support sheaves. A sheave mounted on the riser arm intersects and supports the cable when the elongate member is lowered. As the elongate member is lowered, the riser post supports an increasing portion of the downward load. The net load on the cable is reduced and the elongate member can be elevated from a horizontal or near horizontal position with much less force.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.