Vehicle load lifting and lowering units
US3968890A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 8, 1975 |
| Grant date | Jul 13, 1976 |
| Priority date | — |
| Expiry date | Apr 8, 1995 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S414/13
- WIPO fieldTransport
- WIPO sectorMechanical engineering
Abstract
There are disclosed two forms of load lifting and lowering unit for attachment to a vehicle. The units are of the kind in which a load platform is carried between two parallel spaced-apart articulated parallelogram linkages, movable in unison up and down guide members spaced across an access opening of the vehicle to raise and lower a load to and from the access opening. An inextensible tie member, pivotally connected between the platform and a swinging arm of the parallelogram linkage, causes the platform automatically to close off the access opening when the linkages are folded towards the vehicle. In one embodiment, the swinging arm cooperates with a fixed stop during upward movement of the linkages to effect such closure: in the other embodiment, a fluid operated ram swings the platform upwardly about its pivot to fold the linkages towards the vehicle and cause the platform to close off the access opening.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.