Hydraulically operated dockboard
US4365374A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Aug 4, 1980 |
| Grant date | Dec 28, 1982 |
| Priority date | — |
| Expiry date | Aug 4, 2000 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB65G69/2823
- WIPO fieldHandling
- WIPO sectorMechanical engineering
Abstract
A hydraulically operated dockboard comprising a ramp which is hinged at its rear edge to the frame of the dockboard, and a lip is hinged to the forward edge of the ramp and can be pivoted between a downwardly hanging pendant position and an extended position. A main hydraulic cylinder unit interconnects the frame and the ramp, and by operating the cylinder unit the ramp can be pivoted upwardly from a horizontal cross traffic position to an upwardly inclined position. As the ramp approaches its fully raised position, hydraulic fluid is conducted from the main cylinder unit to a lip lifting cylinder which interconnects the ramp and the lip. Introducing fluid to the lip lifting cylinder will act to pivot the lip to the extended position. When operation of the main hydraulic unit is discontinued, the combined weight of the ramp and the lip will cause the ramp to descend, and when the ramp descends to a predetermined position, the hydraulic fluid will return from the lip lifting cylinder to the main cylinder unit to thereby permit the lip to pivot by gravity to the pendant position.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.