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US 5,029,839 AGranted
Sheet feeding apparatus
AssigneeCanon Kabushiki Kaisha
InventorsNorio Kajiwara, Takeshi Matoba, Junichi Suzuki
Life of this patent
Estimating the term…
Abstract
A sheet feeding apparatus of the invention comprises a conveying belt which is driven in such a direction as to send sheets, a belt or the like which is driven in the direction opposite to the belt conveying direction so as to apply a predetermined resistance force to the feeding of the sheets, and a frictional member adapted to be come into pressure contact with the conveying belt through the sheets. With the apparatus, the sheets can be certainly separated one by one irrespective of the material and thickness of the sheet.
Claims16
A sheet feeding apparatus, comprising:
- means for feeding stacked sheets;
- a conveying belt rotatable to convey the sheets fed by said feeding means in a predetermined direction, said conveying belt contacting a first surface of the sheet for applying a frictional force thereto;
- a first separating means for applying a frictional force to the sheets conveyed by said conveying belt in a direction contrary to said predetermined direction, said first separating means applying a frictional force to a second surface of the sheet to separate the sheets, said first separating means having a curved stationary separating surface contacting said conveying belt to apply said frictional force to the sheet,
- the coefficient of friction between said stationary separating surface and the sheet being selected to be smaller than the coefficient of friction between said conveying belt and the sheet, and larger than the coefficient of friction between sheets;
- a second separating means for applying a frictional force on a downstream side of said first separating means to the sheets conveyed by said conveying belt in a direction contrary to said predetermined direction, said second separating means applying a frictional force to the second surface of the sheet to separate the sheets, said second separating means having a movable separating surface moving in a direction contrary to said predetermined direction for applying said frictional force to the sheets, and
- the coefficient of friction between said movable separating surface and the sheet being selected to be smaller than the coefficient of friction between said conveying belt and the sheet, and larger than the coefficient of friction between sheets.
3 more elements
A sheet feeding apparatus, comprising:
- means for feeding stacked sheets;
- a conveying belt rotatable to convey the sheets fed by said feeding means in a predetermined direction, the conveying belt contacting a first surface of the sheet for applying a frictional force thereto;
- a first separating means for applying a frictional force to the sheets conveyed by said conveying belt in a direction contrary to said predetermined direction, said first separating means applying a frictional force to a second surface of the sheet to separate the sheets, said first separating means having curved stationary separating surface contacting said conveying belt to apply said frictional force to the sheet,
- the coefficient of friction between said stationary separating surface and the sheet being selected to be smaller than the coefficient of friction between said conveying belt and the sheet, and larger than the coefficient of friction between sheets;
- a second separating means which is on a downstream side of said first separating means in contract with the sheets to apply a frictional force thereto in a direction contrary to said predetermined direction, said second separating means applying a frictional force to the second surface of the sheet to separate the sheets;
- the coefficient of friction between said second separating means and the sheet being selected to be smaller than the coefficient of friction between said conveying belt and the sheet, and larger than the coefficient of friction between sheets;
- and
- a first portion of said first separating means which is in contact with the sheets and a second portion of said second separating means which is in contact with the sheets are made from different materials.
5 more elements
An image reading apparatus, comprising:
- means for stacking sheets having an image thereon;
- means for feeding the sheets stacked on said stacking means;
- a conveying belt rotatable to convey the sheets fed by said feeding means in a predetermined direction, said conveying belt contacting a first surface of the sheet for applying a frictional force thereto;
- a first separating means for applying a frictional force to the sheets conveyed by said conveying belt in a direction contrary to said predetermined direction, said first separating means applying a frictional force to a second surface of the sheet to separate the sheets, said first separating means having a curved stationary separating surface contacting said conveying belt to apply said frictional force to said sheet;
- the coefficient of friction between said stationary separating surface and the sheet being selected to be smaller than the coefficient of friction between said conveying belt and the sheet, and larger than the coefficient of friction between sheets;
- a second separating means for applying a frictional force on a downstream side of said first separating means to the sheets conveyed by said conveying belt in a direction contrary to said predetermined direction, said second separating means applying a frictional force to the second surface of the sheet to separate the sheets, said second separating means having a movable separating surface moving in a direction contrary to said predetermined direction for applying said frictional force to the sheets;
- the coefficient of friction between said movable separating surface and the sheet being selected to be smaller than the coefficient of friction between said conveying belt and the sheet, and larger than the coefficient of friction between sheets;
- a first portion of said first separating means which is in contact with the sheets and a second portion of said second separating means which is in contact with the sheets are made from different materials;
- and
- means for reading on a downstream side of said second separating means images on the sheets conveyed.
7 more elements
A sheet feeding apparatus, comprising:
- means for feeding stacked sheets;
- a conveying belt rotatable to convey the sheets fed by said feeding means in a predetermined direction, the conveying belt contacting a first surface of the sheet for applying the frictional force thereto;
- a friction member disposed in a position opposing said conveying belt to hold the sheet together with said conveying belt, the friction member contacting a second surface of the sheet to apply the frictional force thereto,
- the coefficient of friction between the friction member and the sheet being selected to be smaller than the coefficient of friction between said conveying belt and the sheet and larger than the coefficient of friction between the sheets;
- a separating belt disposed in a position unopposed to said conveying belt to contact the second surface of the sheet downstream, with respect to said predetermined direction, of the position at which said friction member contacts the second surface of the sheet to apply the conveying force in the direction contrary to the predetermined direction,
- the coefficient of friction between said separating belt and the sheet being selected to be smaller than the coefficient of friction between said conveying belt and the sheet and larger than the coefficient of friction between the sheets,
- a portion at which said friction member contacts the sheet and a portion at which said separating belt contacts the sheet being composed of different kinds of materials.
4 more elements
Dependencies are inferred from the claim text.