US 4,366,591 AGranted

Automatic safety gangplank

OwnerMahlon N. Zimmermaninventor

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Abstract

The automatic safety gangplank includes a plurality of cooperating ladder sections which are extendable from a fully telescoped or retracted position to an elongated position for extension from a dock to the deck of a ship. The end of the base ladder section is connected to a rotatable turntable and is equipped with a pair of lift cylinders. The turntable and the lift cylinders are connected to respectively rotate and elevate the base segment at all times, when the other gangplank ladder sections are either in their extended or retracted positions. A gangway extends from the end of the outermost ladder section in angular relationship and is positioned upon the deck of the ship. Automatic controls which are responsive to changes in elevation of the deck relative to the dock are provided to automatically either extend, retract, elevate or lower the safety gangplank as may be necessary to continuously maintain a safe walkway between the dock and the deck of the ship for all relative positions of the deck when the ship is either simply docked or when it is being loaded or unloaded.

Claims36

Dependent claims

In an extendable walkway of the type suitable to extend from a construction of fixed elevation to the deck of a ship, wherein the deck is movable between a lower elevation and higher elevation, the combination of

extendable gangplank means to span the distance from the elevation of the construction to elevation of the deck,
the extendable gangplank means comprising at least a base segment and a fly segment,
the fly segment being adapted to move in longitudinal telescoping relationship to the base segment,
the base segment having a connected end and an elevating end;
and
the fly segment terminating outwardly from the base segment in a free end;
extending means interconnected between the base segment and the fly segment to longitudinally move the fly segment relative to the base segment;
elevating means interconnected between the construction and the gangplank means to elevate a portion of the gangplank means about the connected end of the base segment;
walkway means pivotally connected to the gangplank means, the walkway means being adapted to contact the deck, the walkway means extending between the deck and a portion of the gangplank means,
the walkway means being adapted to angularly move relative to the gangplank means when the elevation of the deck is varied;
and
first gangplank movement control means comprising an active element in contact with a portion of the walkway means, the first gangplank movement control means being adapted to monitor a change in angularity of the walkway means about a horizontal axis in response to a change in deck elevation,
the elevating means being adapted to be activated in response to change in deck elevation monitored by the first gangplank movement control means to elevate or lower a portion of the gangplank means.

10 more elements

In an automatic safety gangplank for extending from a construction of fixed elevation to a surface of movable elevation, the combination of

a multi-segment gangplank comprising at least a base segment and a fly segment in telescoping arrangement therewith and extending between the fixed construction and the movable surface,
the base segment having one end pivotally affixed to the fixed construction by a turntable, the turntable having a vertical axis and a horizontal axis, the base segment being adapted to rotate about the vertical axis upon movement of the turntable and to rotate about the horizontal axis;
means to elevate and lower the gangplank when the elevation of the movable surface changes by rotating the base segment about the horizontal axis;
means to extend and retract the fly segment relative to the base segment to change the overall length of the gangplank;
walkway means extending angularly from the fly segment and contacting the said movable surface,
the walkway means being adapted to rotate in a substantially vertical plane about its connection to the fly segment and being adapted to rotate in a substantially horizontal plane about its connection to the fly segment;
first automatic means to adjust the length of the gangplank in response to a predetermined amount of rotation in a horizontal plane of the walkway means to maintain contact between the walkway means and the movable surface;
and
second automatic means to adjust the elevation of the gangplank means in response to a predetermined amount of rotation in a vertical plane of the walkway means to maintain contact between the walkway means and the movable surface;
whereby an automatically extendable and elevatable safety gangplank responsive to changes in elevation of the movable surface is provided.

7 more elements

Dependencies are inferred from the claim text.

Facts

Application: 06/205,932Filed 12 Nov 1980
Granted: 4 Jan 1983
Term ends: Not estimatedThe source records don’t support an estimate.

Classification5 codes

E01D 15/24
Movable or portable bridges; Floating bridges: bridges or similar structures, based on land or on a fixed structure and designed to give access to…
B63B 27/14
Arrangement of ship-based loading or unloading equipment for cargo or passengers: of ramps, gangways or outboard ladders ; Pilot lifts
B63B 2027/141
Of ramps, gangways or outboard ladders ; Pilot lifts: telescopically extendable
E01D
Construction of bridges, elevated roadways or viaducts