Pallet lifting fork truck
US6616395B2 · kind B2 · utility
Inventor
Key dates
| Filing date | Sep 19, 2001 |
| Grant date | Sep 9, 2003 |
| Priority date | — |
| Expiry date | Oct 9, 2021 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB62B2301/20
- WIPO fieldTransport
- WIPO sectorMechanical engineering
Abstract
Springing for support wheels of low lifting trucks arranged below the forks includes a common spring device arranged in the transfer mechanism of the lifting movement to the support wheels. The spring device includes a cylinder, a piston, a spring package of cup springs and an extending push rod that in the cylinder is connected a ring shaped element located between the spring package and the cylinder end through which the push rod extends. The piston is arranged in the other end of the spring package and the cylinder is via a return valve coupled in parallel with the load lifting hydraulic system of the truck so that the pressure in this pretensions the ring shaped element towards the cylinder end proportionally to the load, so that springing does not take place until the dynamics forces overcome the pretension.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.