Sheet feeder
AssigneeMinnesota Mining and Manufacturing Company
InventorRaymond A. Hogenson
Life of this patent
Estimating the term…
Abstract
A sheet feeder for feeding sheets from a stack thereof, which feeder automatically fans or separates the uppermost sheets within the stack to facilitate their feeding. The feeder includes a feed roll brake releasably coupled to a feed roll which brake rotates with the feed roll until a pre-determined force is applied on the brake by a spring that has been compressed by the normal feeding rotation of the feed roll, causing the feed roll to rotate in the opposite direction to the normal feed direction, thereby fanning the uppermost sheets.
Claims5
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.
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.
Dependencies are inferred from the claim text.