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US 4,329,082 AGranted
Shiplift apparatus
OwnerMichael E. Gillisinventor
Life of this patent
Estimating the term…
Abstract
The present shiplift apparatus has a horizontal lift platform with eight lift points (four on each side along the length of the platform). Four lift motors are provided, each operating a first cable for lifting the platform at a lift point which is located toward the longitudinal, midpoint of the platform and a second cable for lifting the platform at a lift point near one end or the other of the platform. Each second cable is connected to a linear actuator for leveling up the platform independent of the lift motors.
Claims19
In an apparatus for lifting or lowering a water-borne structure, said apparatus having:
- a dock having spaced apart, opposite sides and an open end between said sides through which the water-borne structure can enter and leave;
- a support platform extending between said opposite sides and movable vertically between a lowered position below water and raised position above water, said support platform comprising a plurality of longitudinal horizontal beams spaced apart laterally from each other and each extending generally parallel to said opposite sides of the dock, and a plurality of transverse horizontal beams extending substantially perpendicular to said longitudinal beams and rigidly attached thereof, said transverse beams including main beams at intervals along the length of said longitudinal beams and secondary beams at shorter intervals between successive main beams;
- the improvement which comprises:
- on each side of the dock, a single drive motor for each pair of main transverse beams in succession along the length of said platform, said motor being mounted on the corresponding side of the dock;
- a pair of intercoupled drums driven by each said motor;
- a respective first set of lower pulleys mounted on one of said pair of main transverse beams at the end thereof adjacent said corresponding side of the dock;
- a respective first set of upper pulleys mounted on said corresponding side of the dock;
- a respective first flexible cable fastened at one end to one of said drums of the corresponding pair and fastened at its opposite end to said corresponding side of the dock, said cable operatively engaging the pulleys of the corresponding first set of upper pulleys and the pulleys of the corresponding first set of lower pulleys and extending between them to impart an upward force to said one main transverse beam upon rotation of said corresponding one drum in one direction;
- a respective second set of lower pulleys mounted on the other main transverse beam of said pair at the end of said beam adjacent said corresponding side of the dock;
- a respective second set of upper pulleys mounted on said corresponding side of the dock;
- and a respective second flexible cable fastened at one end to the other of said drums of the corresponding pair and operatively connected at its opposite end to said corresponding side of the dock, said second cable operatively engaging the pulleys of the corresponding second set of upper pulleys and the pulleys of the corresponding second set of lower pulleys and extending between them to impart an upward force to said other main transverse beam upon rotation of said other drum in one direction;
- said first and second cables leading in divergent direction from said first and second drums respectively.
9 more elements
In an apparatus for lifting or lowering a water-borne structure, said apparatus having:
- a dock having spaced apart, opposite sides and an open end between said sides through which the water-borne structure can enter and leave;
- a support platform extending between said opposite sides and movable vertically between a lowered position below water and raised position above water, said support platform comprising a plurality of longitudinal horizontal beams spaced apart laterally from each other and each extending generally parallel to said opposite sides of the dock, and a plurality of transverse horizontal beams extending substantially perpendicular to said longitudinal beams and rigidly attached thereto, said transverse beams including main beams at intervals along the length of said longitudinal beams and secondary beams at shorter intervals between successive main beams;
- the improvement which comprises:
- on each side of the dock, a single drive motor for each pair of main transverse beams in succession along the length of said platform, said motor being mounted on the corresponding side of the dock;
- a pair of intercoupled drums driven by each said motor;
- a respective first set of lower pulleys mounted on one of said pair of main transverse beams at the end thereof adjacent said corresponding side of the dock;
- a respective first set of upper pulleys mounted on said corresponding side of the dock;
- a respective first flexible cable fastened at one end to one of said drums of the corresponding pair and fastened at its opposite end to said corresponding side of the dock, said cable operatively engaging the pulleys of the corresponding first set of upper pulleys and the pulleys of the corresponding first set of lower pulleys and extending between them to impart an upward force to said one main transverse beam upon rotation of said corresponding one drum in one direction;
- a respective second set of lower pulleys mounted on the other main transverse beam of said pair at the end of said beam adjacent said corresponding side of the dock;
- a respective second set of upper pulleys mounted on said corresponding side of the dock;
- and a respective second flexible cable fastened at one end to the other of said drums of the corresponding pair and operatively connected at its opposite end to said corresponding side of the dock, said second cable operatively engaging the pulleys of the corresponding second set of upper pulleys and the pulleys of the corresponding second set of lower pulleys and extending between them to impart an upward force to said other main transverse beam upon rotation of said other drum in one direction;
- and adjusting means acting on said opposite end of each of said second cables for adjusting the latter's length between the corresponding second set of upper pulleys and the corresponding second set of lower pulleys, whereby to adjust the vertical position of the platform.
9 more elements
In an apparatus for lifting or lowering a water-borne structure, said apparatus having:
- a dock having spaced apart, opposite sides and an open end between said sides through which the water-borne structure can enter and leave;
- a support platform extending between said opposite sides and movable vertically between a lowered position below water and raised position above water, said support platform comprising a plurality of longitudinal horizontal beams spaced apart laterally from each other and each extending generally parallel to said opposite sides of the dock, and a plurality of transverse horizontal beams extending substantially perpendicular to said longitudinal beams and rigidly attached thereto, said transverse beams including main beams at intervals along the length of said longitudinal beams and secondary beams at shorter intervals between successive main beams;
- a drive motor mounted on one side of the dock;
- a rotary drum on said one side of the dock driven by said motor;
- a set of lower pulleys mounted on one of said main transverse beams at the end thereof adjacent said one side of the dock;
- a set of upper pulleys mounted on said one side of the dock above said set of lower pulleys;
- and a flexible cable fastened at one end to said drum and operatively engaging said upper and lower pulleys and extending between them to impart an upward force to said one main transverse beam upon rotation of said drum in one direction;
- the improvement which comprises:
- fluid-operated adjusting means acting on said opposite end of said cable for adjusting the latter's length between said set of upper pulleys and said set of lower pulleys, whereby to adjust the vertical position of the platform at said main transverse beam while the platform is under load.
6 more elements
Dependencies are inferred from the claim text.