Jib derricking gear for a crane
US4967917A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 28, 1989 |
| Grant date | Nov 6, 1990 |
| Priority date | — |
| Expiry date | Jun 28, 2009 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB66C23/702
- WIPO fieldHandling
- WIPO sectorMechanical engineering
Abstract
A jib derricking gear for a jib crane having a boom and a jib for hoisting work extended from the boom head of the boom comprises a pair of jib derricking cylinder actuators. Load on the jib is distributed to the pair of jib derricking cylinder actuators, so that each jib derricking cylinder actuator may be such as having a cylinder having a comparatively small diameter. The jib derricking cylinder actuators are combined with the jib so that the jib derricking cylinder actuators function as compression members. The thrust of the jib derricking cylinder actuator is doubled by a tackle. The jib derricking cylinder actuators and the associated jib supporting members are disposed so that the jib derricking cylinder actuators and the associated jib supporting members will not interfere with a hoist rope for hoisting work.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.