Multistage telescope boom
US5501346A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jan 9, 1995 |
| Grant date | Mar 26, 1996 |
| Priority date | — |
| Expiry date | Jan 9, 2015 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF15B11/205
- WIPO fieldHandling
- WIPO sectorMechanical engineering
Abstract
A multistage telescopic boom or jib, in particular for a loading crane on a truck, has hydraulic units each including a piston and a cylinder arranged between the successive, telescopically nested arms. A pipe projects axially from the bottom of the cylinder into the chamber of the cylinder, sealingly extending into the hollow piston rod when the piston is retracted and sealing the chamber of the cylinder from an inner chamber of the hollow piston rod. In order to ensure an automatic extension sequence of the telescopic arms, the inner chamber of each hollow piston rod is linked to the cylinder chamber of the next outer hydraulic unit by a preferably rigid line, and the inner chamber of each hollow piston rod communicates with the cylinder chamber of the same hydraulic unit when the piston is fully extended.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.