Extended safety cage for retractable gangway
AssigneeAluminum Ladder Company
InventorRonald W. Bennett
Life of this patent
Estimating the term…
Abstract
An extended safety cage provides access to a plurality of hatches on the top of a mobile container. The cage is rotatably attached to the end of a gangway, which extends from and is rotatably attached to a platform. The platform carries a pair of braces that extend out in opposite directions and support the cage through spring-loaded lifting arms. The apparatus can include actuators, such as hydraulic or pneumatic actuators, that urge the gangway and cage downward when activated. Secondary braces ensure that the lifting arms and safety cage move in unison.
Claims13
An apparatus for providing safe access to a top of a mobile container, said mobile container having a top, a longitudinal dimension, and a plurality of hatches arrayed along said longitudinal dimension on said top, said apparatus comprising:
- a raised platform;
- a pair of braces carried by said platform and extending away from said platform in opposite directions from one another and parallel to said longitudinal dimension of said mobile container;
- a gangway having a first end and an opposing second end, said first end of said gangway rotatably attached to said platform, said gangway extending laterally outward from said platform, said gangway rotatable in a vertical plane from a downward position to a substantially vertical upward position;
- an extended cage attached to said second end of said gangway with an access opening at said second end of said gangway, said cage dimensioned to encompass all of said plurality of hatches simultaneously, said cage rotatable on said second end of said gangway so that said cage remains horizontal when said gangway is in said horizontal position and when said gangway is in said vertical position;
- a pair of lifting arms rotatably attached to said pair of braces and said cage and urging said cage upward.
A safety cage for providing fall protection to workers working on top of a mobile container having a plurality of hatches, said safety cage comprising:
- a pair of spaced-apart, parallel long sides in opposed relation, one side of said pair of said long sides connected to an end of a gangway and having an access opening at said end of said gangway;
- a pair of spaced-apart, parallel short sides in opposed relation, said short sides connecting said pair of long sides to create a quadrilateral;
- and
- at least one tracking gate carried by said cage, said at least one tracking gate extending into said cage parallel to said pair of short sides and movable within said cage so that said cage can be dimensioned to encompass said plurality of hatches but not extend beyond said top of said mobile container.
An apparatus for providing access to a top of a mobile container, said mobile container having a top, a longitudinal dimension, and a plurality of hatches arrayed along said longitudinal dimension on said top, said apparatus comprising:
- a raised platform;
- a pair of braces carried by said platform and extending away from said platform in opposite directions from one another and parallel to said longitudinal dimension of said mobile container;
- a gangway having a first end and an opposing second end, said first end of said gangway rotatably attached to said platform, said gangway extending laterally outward from said platform, said gangway rotatable in a vertical plane from a downward position to a substantially vertical upward position;
- an extended cage attached to said second end of said gangway with an access opening at said second end of said gangway, said cage dimensioned to encompass all of said plurality of hatches simultaneously, said cage rotatable on said second end of said gangway so that said cage remains horizontal when said gangway is in said horizontal position and when said gangway is in said vertical position;
- a pair of outboard uprights extending upward from said pair of braces;
- two pairs of parallel linkages connecting said outboard uprights to said cage;
- a pair of springs spanning from said outboard uprights to said pairs of parallel linkages so that said pair of springs urge said cage upward;
- a pair of inboard uprights extending upward from said platform;
- a pair of actuating cylinders connected to said pair of inboard uprights and said gangway so that, when said actuating cylinders are extended, said gangway is lowered and said cage encompasses all of said plurality of hatches.
A method of providing safe access to a mobile container, said mobile container having a top, a longitudinal dimension, and a plurality of hatches arrayed along said longitudinal dimension on said top, said method comprising:
- providing a raised platform adjacent to said top of said mobile container;
- providing a pair of braces carried by said platform and extending away from said platform in opposite directions from one another and parallel to said longitudinal dimension of said mobile container;
- providing a gangway having a first end and an opposing second end, said first end of said gangway rotatably attached to said platform, said gangway extending laterally outward from said platform, said gangway rotatable in a vertical plane from a downward position to a substantially vertical upward position;
- providing an extended cage attached to said second end of said gangway with an access opening at said second end of said gangway, said cage dimensioned to encompass all of said plurality of hatches simultaneously, said cage rotatable on said second end of said gangway so that said cage remains horizontal when said gangway is in said horizontal position and when said gangway is in said vertical position;
- providing a pair of lifting arms rotatably attached to said pair of braces and said cage and urging said cage upward;
- providing at least one actuating cylinder between said gangway and said platform, said actuating cylinder positioned and dimensioned to urge said gangway downward when extended;
- and
- extending said actuating cylinder and thereby lowering said cage over said top of said mobile container so that said cage provides safe access to all of said plurality of hatches.
Dependencies are inferred from the claim text.