Linked-spar motion-compensated lifting system

Patent 4280430 Issued on July 28, 1981. Estimated Expiration Date:

January 26, 1999. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.

Abstract Claims Description Full Text

Patent References

3782458

3912088

Mooring buoy
Patent #: 3950806
Issued on: 04/20/1976
Inventor: Puchois

Mooring terminal
Patent #: 4010500
Issued on: 03/08/1977
Inventor: Reid, Jr.

Riser and yoke mooring system
Patent #: 4088089
Issued on: 05/09/1978
Inventor: Flory

Deep water berthing system for very large cargo carriers
Patent #: 4150636
Issued on: 04/24/1979
Inventor: Lundh

Floating installation connected to a stationary underwater installation through at least one flexible pipe Patent #: 4173804
Issued on: 11/13/1979
Inventor: Duc

Inventors

Application

No. 06/006825 filed on 01/26/1979

US Classes:

114/51, Hoisting212/272, HAVING MEANS TO PREVENT OR DAMPEN LOAD OSCILLATIONS212/273, Antisway (i.e., horizontal movements)212/308, Including counterweight or means to compensate for list, trim or skew of vessel441/3For mooring a vessel

Examiners

Primary: Blix, Trygve M.
Assistant: Keen, D. W.

Attorney, Agent or Firm

International Classes

B63B 22/00 (20060101)
B63B 27/00 (20060101)
B63B 27/16 (20060101)
B66C 13/02 (20060101)
B63B 22/02 (20060101)
B66C 13/00 (20060101)

Abstract

A system for operating a lifting cable over the side of a ship at sea in ch a spar buoy having an adjustable lifting capacity is coupled to the ship by a rigid linkage which is free to pivot on an axis attached to the deck. The lifting cable is suspended from a first sheave which is mounted above a central, longitudinal channel in the spar buoy. The linkage is attached to the top of the spar buoy such that the spar buoy may rotate about an axis normal to the deck axis of the linkage and pivot on an axis normal to the longitudinal axis of the spar buoy. A second sheave is mounted on the deck axis so that the distance between the sheaves does not change as the linkage rotates on its axis. The lifting cable is fed from a winch on the ship over the sheaves and falls through the longitudinal channel. The invention operates to decouple the motion of the ship from the lifting cable so that the vertical motion of the cable is controlled by the motion of the spar buoy. A topping lift technique for deck-handling the system and an emergency disconnect feature are also disclosed.