Telescopic ram
US4041839A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 24, 1975 |
| Grant date | Aug 16, 1977 |
| Priority date | — |
| Expiry date | Nov 24, 1995 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB66F9/22
- WIPO fieldHandling
- WIPO sectorMechanical engineering
Abstract
A multistage, extensible-contractible hydraulic ram assembly for use in conjunction with a triple-lift-type mast in a lift truck. The assembly is designed for mounting in such a truck in a so-called inverted position. It is constructed with special, externally actuated, internal valving which, through controlling the action of pressure fluid within the assembly, assures positive control over the sequence of movements of the sections in a mast as such are raised and lowered, without requiring latching and interlocking of these sections. Further, the assembly features the capability of producing substantially uniform or constant lifting and lowering speeds for a load which is carried on the usual carriage mounted on a mast of the type indicated.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.