Marine crane lifting control
US4304337A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 29, 1980 |
| Grant date | Dec 8, 1981 |
| Priority date | — |
| Expiry date | May 29, 2000 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB66D1/52
- WIPO fieldHandling
- WIPO sectorMechanical engineering
Abstract
A marine crane includes a high speed winch having a hydraulic heave compensating system that automatically controls the crane winch to compensate for the vertical movement of a load during offloading operations. The heave compensating system includes a reversing valve for overriding manual control and for directing control pressure to stroke the pump of a hydrostatic winch drive into its raise mode of operation, and a compensating valve that regulates the displacement of the pump permitting it to develop and maintain only a predetermined pressure in the high pressure main fluid line. The heave compensating system preferably includes a lift control system for automatically hoisting a heaving load only at or near the crest or trough of a wave.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.