Multiple RAM assembly and recuperative drive system for hydraulic lift
US5636713A · kind A · utility
Inventors
Key dates
| Filing date | Feb 28, 1995 |
| Grant date | Jun 10, 1997 |
| Priority date | — |
| Expiry date | Feb 28, 2015 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02B50/00
- WIPO fieldHandling
- WIPO sectorMechanical engineering
Abstract
A multi-stage hydraulic ram assembly for the accumulator drive system of an elevator assembly includes a plurality of piston-cylinder arrangements connected hydraulically in parallel and mechanically in series. The piston-cylinder arrangements are disposed in substantial side-by-side relationship, constituting adjacent or successive stages of the ram assembly. A bracket is fixed to one of the cylinders and is slidably connected to the adjacent cylinder, for interconnecting adjacent cylinders of the piston-cylinder arrangements, and a drive system is provided for operating the ram assembly. Steps are taken to control the direction and speed of movement of adjacent stages of the assembly, and to ensure that all of the stages of the assembly move at substantially the same speed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.