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US4787810A Expired / Lapsed US ⏱️ 0.0 years remaining

Method and apparatus for handling stacks of loose sheet material

Assignee: Individual
•
Filing: 1987-09-04
•
Granted: 1988-11-29
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Expires: 2007-09-04
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Abstract

Abstract A movable body having a pair of parallel arms supported from the body and in turn supporting a pair of forks for movement for engaging and releasing the bottom of a stack of sheet material. A clamp is movably connected to the body above the forks for engaging the top of the material and holding the material between the clamp and the extended forks. A probe lifter is movably connected to the body and movable between a lower position below the forks and an upper position between the extended forks for removing the weight of the stack from the forks for allowing the forks to be retracted.

Inventors

  • 👤 Wesley D. Cawley
  • 👤 Clifton M. Cawley

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-06 16:17
CPC Classifications
B; B65; B65H; B65H31/00; B65H31/30; B65H31/3036; B65H31/3045; B65G; B65G61/00; B65H2301/00; B65H2301/40; B65H2301/42; B65H2301/422; B65H2301/4224; B65H2301/42242; B65H2301/4225; B65H2301/42256; Y; Y10; Y10S; Y10S414/00; Y10S414/13

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 221 words
An apparatus for handling stacks of loose sheet material comprising, a movable body having a front face, a pair of parallel arms forming a parallelogram linkage pivotally connected at their upper ends to and supported from the body for movement toward and away from the front face, a pair of forks pivotally connected to the lower ends of the arms and positioned and movable generally horizontally from beneath the body to a position outside of the front face of the body for engaging and releasing only a portion of the bottom of a stack of material, moving means connected between the body and the arms for extending and retracting the forks, a clamp positioned outside of the body and pivotally connected to the body for engaging the top of the stack and holding the stack between the clamp and the extended forks, means connected to the clamp for moving the clamp toward and away from the forks, a probe lifter pivotally connected to the body and positioned outside of the body and movable between a lower position below the forks and an upper position between the extended forks for removing the weight of the stack from the forks, said lifter including a roller, and means connected to the lifter for moving the lifter from the lower position to the upper position.
Claim 2
Independent Claim 221 words
An apparatus for handling stacks of loose sheet material comprising, a movable body having a front face, a pair of parallel arms forming a parallelogram linkage pivotally connected at their upper ends to and supported from the body for movement toward and away from the front face, a pair of forks pivotally connected to the lower ends of the arms and positioned and movable generally horizontally from beneath the body to a position outside of the front face of the body for engaging and releasing only a portion of the bottom of a stack of material, moving means connected between the body and the arms for extending and retracting the forks, a clamp positioned outside of the body and pivotally connected to the body for engaging the top of the stack and holding the stack between the clamp and the extended forks, means connected to the clamp for moving the clamp toward and away from the forks, a probe lifter pivotally connected to the body and positioned outside of the body and movable between a lower position below the forks and an upper position between the extended forks for removing the weight of the stack from the forks, said lifter including a roller, and means connected to the lifter for moving the lifter from the lower position to the upper position.
Claim 3
Dependent Claim 21 words
The apparatus of claim 1 including, a vacuum pickup connected to the body for picking up and depositing a slip sheet.
Claim 4
Dependent Claim 26 words
The apparatus of claim 2 wherein the pickup is movably connected to the body, and means connected to the pickup for lowering and raising the pickup.
Claim 5
Dependent Claim 20 words
The apparatus of claim 1 wherein the forks are directed downwardly and outwardly at an angle of approximately 5 degrees.
Claim 6
Independent Claim 112 words
The method of handling a stack of loose sheet material comprising, placing a pair of forks beneath a portion of the stack of sheet material, holding the stack between a clamp on the top of the stack and the forks, moving the stack to a desired location, transferring a portion of the weight of the stack to a stacking surface, releasing the clamp from the top of the stack, moving a roller upwardly between the forks and against the bottom of the stack to remove the weight of the stack from the forks, retracting the forks downwardly and away from the stack, and removing the roller from the bottom of the stack.
Claim 7
Independent Claim 112 words
The method of handling a stack of loose sheet material comprising, placing a pair of forks beneath a portion of the stack of sheet material, holding the stack between a clamp on the top of the stack and the forks, moving the stack to a desired location, transferring a portion of the weight of the stack to a stacking surface, releasing the clamp from the top of the stack, moving a roller upwardly between the forks and against the bottom of the stack to remove the weight of the stack from the forks, retracting the forks downwardly and away from the stack, and removing the roller from the bottom of the stack.

References Cited (Backward Citations)

US3272364A Cited
DE2300689A1 Cited
US4505635A Cited
US4383788A Cited
DD226267A1 Cited
JPH112234A Cited
JPH11561A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1991-11-29 1992-05-30 1992-11-29 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1995-11-29 1996-05-30 1996-11-29 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1999-11-29 2000-05-30 2000-11-29 $7700.00 Window Closed / Lapsed

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