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US 4,162,873 AGranted
Extensible boom lift
OwnerRaymond E. Smith, Jr.inventor
Life of this patent
Estimating the term…
Abstract
A workpiece lift including a pivotable boom with a pivot end that moves horizontally as the load end of the boom is raised and lowered, allowing the load end to move along a substantially vertical line. In a preferred embodiment the load end of the boom terminates in a workpiece arm which supports a workpiece and which extends downwardly from the load end of the boom so that the workpiece may be lifted upwardly and outwardly in an arc.
Claims16
A lift for raising a workpiece, comprising:
- a pivotal boom having an extensible load end terminating in an upper reach and a pivot end;
- means for supporting said boom so that said boom pivot end is horizontally movable but substantially vertically fixed;
- a support arm having one end held from substantial horizontal motion and pivotally mounted for rotation about a substantially horizontal axis and a second end pivotally mounted to said boom;
- means for raising and lowering said boom so that as said boom load end is elevated, its boom pivot end responds by moving substantially horizontally toward said support arm;
- a workpiece arm extending from the load end of said boom;
- means for supporting the workpiece on said workpiece arm at a location below the upper reach of the load end of said boom;
- and
- means for continuously extending said extensible load end as said load end is elevated, whereby said workpiece arm is elevated and lifts the workpiece in an arc such that the workpiece is extended farther horizontally from the lift when in its elevated position than when in its unelevated position.
5 more elements
A lift for raising a workpiece, comprising:
- a pivotable boom having an extensible load end terminating in an upper reach and a pivot end;
- means for supporting said boom so that said boom pivot end is horizontally movable but substantially vertically fixed;
- a support arm having one end pivotally mounted for rotation about a substantially horizontal axis and a second end pivotally mounted to said boom;
- means for raising and lowering said boom so that as said boom load end is elevated, its boom pivot end moves substantially horizontally toward said support arm, said raising and lowering means including a telescoping cylinder having one end pivotally mounted for rotation about a substantially horizontal axis substantially parallel to the axis of rotation of said support arm, and having an opposed end;
- an elongated, double-ended coupling pivotally connected at its first end to the pivot end of said boom and pivotally connected at its second end to said opposed end of said telescoping cylinder;
- a workpiece arm extending from the load end of said boom;
- means for supporting the workpiece on said workpiece arm at a location below the upper reach of the load end of said boom;
- and
- means for extending said extensible load end as said load end is elevated, whereby when said telescoping cylinder is actuated to telescope, said coupling rotates about its pivoted connection to the pivot end of said boom so as to optimize the lifting torque applied to said boom by said telescoping cylinder, and
- said workpiece arm is elevated and lifts the workpiece in an arc such that the workpiece is extended farther horizontally from the lift when in its elevated position than when in its unelevated position.
7 more elements
A lift for raising a workpiece, comprising:
- a pivotable boom having an extensible load end and a pivot end;
- means for supporting said boom so that said boom pivot end is horizontally movable but substantially vertically fixed;
- a support arm having one end held from substantial horizontal motion and pivotally mounted for rotation about a substantially horizontal axis and a second end pivotally mounted to said boom;
- an extension of said support arm which extends from the second end of said support arm to beyond said boom;
- means for raising and lowering said boom so that as said boom load end is elevated, its boom pivot end responds by moving substantially horizontally toward said support arm;
- a workpiece arm extending from the load end of said boom for supporting the workpiece;
- and
- elongated boom extending means coupled at one end to the extensible load end of said boom and pivotally connected at its other end to said support arm extension, the pivotal connection between said boom extending means and said support arm extension being located beyond said boom by a distance such that pivoting of said support arm and its extension causes said boom extending means to continuously extend the extensible load end of the boom and the workpiece arm such that the workpiece is lifted in an arc which places the workpiece farther horizontally from the lift when in its elevated position than when in its unelevated position.
5 more elements
A lift for raising a workpiece, comprising:
- a pivotable boom having an extensible load end and a pivot end;
- means for supporting said boom so that said boom pivot end is horizontally movable but substantially vertically fixed;
- a support arm having one end pivotally mounted for rotation about a substantially horizontal axis and a second end pivotally mounted to said boom;
- an extension of said support arm which extends from the second end of said support arm to beyond said boom;
- means for raising and lowering said boom so that as said boom load end is elevated, its boom pivot end moves substantially horizontally toward said support arm, said means for raising and lowering said boom including a telescoping cylinder having one end pivotally mounted for rotation about a substantially horizontal axis substantially parallel to the axis of rotation of said support arm, and having an opposed end;
- an elongated, double-ended coupling pivotally connected at its first end to the pivot end of said boom and pivotally connected at its second end to said opposed end of said telescoping cylinder such that when said telescoping cylinder is actuated to telescope, said coupling rotates about its pivotal connection to the pivot end of said boom so as to optimize the lifting torque applied to said boom by said telescoping cylinder;
- a workpiece arm extending from the load end of said boom for supporting the workpiece;
- and
- elongated boom extending means coupled at one end to the extensible load end of said boom and pivotally connected at its other end to said support arm extension, the pivotal connection between said boom extending means and said support arm extension being located beyond said boom by a distance such that pivoting of said support arm and its extension causes said boom extending means to extend the extensible load end of the boom and the workpiece arm such that the workpiece is lifted in an arc which places the workpiece farther horizontally from the lift when in its elevated position than when in its unelevated position.
6 more elements
A lift for raising a workpiece, comprising:
- a pivotal boom having an extensible load end and a pivot end;
- means for supporting said boom so that said boom pivot end is horizontally movable but substantially vertically fixed;
- a support arm having one end pivotally mounted for rotation about a substantially horizontal axis and a second end pivotally mounted to said boom;
- a support arm extension which extends from the second end of said support arm to a position beyond said boom;
- a link coupling said support arm extension to the extensible load end of said boom;
- a workpiece arm coupled to the load end of said boom and extending downwardly and outwardly therefrom;
- means for coupling said workpiece arm to the workpiece;
- a telescoping cylinder having one end pivotally mounted adjacent said one end of said support arm for pivotal rotation about a horizontal axis, and having a second end;
- an elongated, double-ended clevis coupling pivotally connected at one end to said boom and pivotally connected at its opposed end to said second end of said telescoping cylinder,
- whereby the telescoping of said cylinder causes said clevis coupling to rotate about its pivotal connection to said boom and to urge said boom upwardly, the pivot end of said boom moves horizontally toward said support arm, said support arm extension rotates to cause said link to extend the boom load end, and said workpiece arm lifts the workpiece upwardly in an arc away from the lift.
7 more elements
Dependencies are inferred from the claim text.