Load limiting device
US4093092A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 24, 1976 |
| Grant date | Jun 6, 1978 |
| Priority date | — |
| Expiry date | Mar 24, 1996 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB66F17/003
- WIPO fieldHandling
- WIPO sectorMechanical engineering
Abstract
The invention is concerned with an improvement in a load lifting apparatus which comprises a primary load member pivotally mounted about a generally horizontal axis on a frame, a tilt cylinder and a tilt piston movable relative to one another pivotally connected to the frame and the primary load member to provide impetus for pivotal movement therebetween, a secondary load member movable relative to the primary load member, a lift cylinder and a lift piston movable relative to one another connected to the primary load member and the secondary load member to provide impetus for linear relative movement therebetween, tilt cylinder valve means for controlling flow of pressurized fluid from pump means to the tilt cylinder and lift cylinder valve means for controlling flow of pressurized fluid from the pump means to the lift cylinder. The improvement of the invention provides protection which prevents the apparatus from overbalancing. The improvement operates by sensing a moment created by a load on the apparatus. Most particularly, the improvement comprises a valve sensing simultaneously a lift pressure force proportional to a lift pressure in a head end of the lift cylinder and a tilt …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.