Sheet feeder

Claim 2

A sheet feeder comprising frame means for supporting a stack of sheets, a feed roll for feeding said sheets having an axle which is rotatably supported on said frame means, means for affording contact of the uppermost sheet within the stack of sheets with said feed roll, drive means for intermittently rotating said axle, a feed roll brake mounted on said axle, including means for releasably coupling said feed roll brake to said axle affording the rotation of said feed roll brake with said axle, until the application of a predetermined force on said feed roll brake in a direction opposing the rotation of said axle by said drive means, and biasing means for applying said predetermined force, and for rotating said feed roll brake, said axle, and said feed roll in a direction opposite to the direction of rotation caused by said drive means upon the cessation of the rotation of said axle by said drive means, thereby urging the uppermost sheets in the stack of sheets in a direction opposite to the feeding direction, and accordingly fanning the uppermost sheets of said stack of sheets.

Claim 3

A sheet feeder as claimed in claim 1 wherein said feed roll brake includes an elongate first lever arm having a surface adjacent its proximate end which is adapted to receive a portion of the outer circumference of said axle, and a second lever arm having a proximate end pivotally mounted to the proximate end of said first lever arm, said second lever arm also having a surface adjacent its proximate end which is adapted to receive a portion of the outer circumference of said axle, and wherein said means for coupling said feed roll brake to said axle includes means for adjustably biasing the distal ends of said first and second lever arms together to bring said surfaces into frictional contact with said axle, whereby said feed roll brake will rotate with said feed roll as long as the frictional forces between said surfaces and said axle are greater than said predetermined force applied by said biasing means against said feed roll brake, and whereby said feed roll brake will slip with respect to said axle when said frictional forces between said surfaces and said axle are less than or equal to said predetermined force.

Claim 4

A sheet feeder as claimed in claim 2 wherein said means for biasing the distal ends of said first and second lever arms together comprises a bolt, a threaded bore within the distal end of said second lever arm which is adapted to engage said bolt, a larger bore adjacent the distal end of said first lever arm which is adapted to loosely receive said bolt, and a spring positioned between the head of said bolt and the upper portion of said first lever arm.

Claim 5

A sheet feeder as claimed in claim 2 wherein said biasing means for applying said predetermined force on said feed roll brake comprises a spring positioned between said first lever arm and said frame means.

Claim 6

In a sheet feeder for feeding sheets from a stack of sheets, having a driven feed roll which includes a rotatable axle that is mounted on the sheet feeder and drive means which upon being energized rotate the feed roll, the improvement comprising a feed roll brake for use with said sheet feeder which includes a first and a second lever arm hingedly attached on one end, each of said lever arms having an introrsely positioned indentation adjacent said hingedly attached end, which indentation is adapted to receive a portion of the circumference of said axle, means for biasing said second lever arm toward said first lever arm thereby bringing said indentations into frictional contact with said axle to afford the rotation of said lever arms with said axle, and means for biasing said first lever arm in a direction affording the rotation of said first lever arm in the opposite direction to the direction of rotation due to said drive means, the force of which increases with the rotation of said first lever arm, whereby said lever arms will rotate with said axle until the biasing force on said first lever arm equals the frictional forces exerted between said indentations and said axle, at which time said lever arms will slip with respect to said axle; and whereby said feed roll brake and said axle will be rotated in the opposite direction to the direction of rotation due to said drive means, when said drive means are de-energized, thereby fanning the uppermost sheets in said stack of sheets facilitating their separation from each other.

Claim 7

In a sheet feeder for feeding sheets from a stack of sheets, having a driven feed roll which includes a rotatable axle that is mounted on the sheet feeder and drive means which upon being energized rotate the feed roll, the improvement comprising a feed roll brake for use with said sheet feeder which includes a first and a second lever arm hingedly attached on one end, each of said lever arms having an introrsely positioned indentation adjacent said hingedly attached end, which indentation is adapted to receive a portion of the circumference of said axle, means for biasing said second lever arm toward said first lever arm thereby bringing said indentations into frictional contact with said axle to afford the rotation of said lever arms with said axle, and means for biasing said first lever arm in a direction affording the rotation of said first lever arm in the opposite direction to the direction of rotation due to said drive means, the force of which increases with the rotation of said first lever arm, whereby said lever arms will rotate with said axle until the biasing force on said first lever arm equals the frictional forces exerted between said indentations and said axle, at which time said lever arms will slip with respect to said axle; and whereby said feed roll brake and said axle will be rotated in the opposite direction to the direction of rotation due to said drive means, when said drive means are de-energized, thereby fanning the uppermost sheets in said stack of sheets facilitating their separation from each other.