Sheet supplying device
First Claim
1. A sheet supplying device comprising:
- a sheet accommodating portion that accommodates a plurality of sheets in a stacked arrangement;
a feeding portion disposed to be contactable with a topmost sheet of the plurality of sheets with contact force and rotatable in contact with the topmost sheet for conveying the topmost sheet downstream in a conveying direction;
a shifting mechanism that shifts at least one of the sheet accommodating portion and the feeding portion, thereby changing a position of the feeding portion relative to the plurality of sheets in the sheet accommodating portion;
a first separating portion disposed downstream of the feeding portion in the conveying direction;
a second separating portion disposed to be pressed against the first separating portion, the second separating portion being rotatable to separate the topmost sheet from other sheets of the plurality of sheets in cooperation with the first separating portion and to convey the separated sheet in the conveying direction;
a pressure changing mechanism that changes pressure between the first separating portion and the second separating portion;
a contact force controlling portion that controls the shifting mechanism to provide a first contact force when the feeding portion starts a feeding operation for conveying the topmost sheet in the conveying direction, and that controls the shifting mechanism, at a first timing, to reduce the contact force from the first contact force to a second contact force; and
a pressure controlling portion that controls the pressure changing mechanism to provide a first pressure between the first separating portion and the second separating portion when the feeding portion starts the feeding operation, and that controls the pressure changing mechanism, at a second timing, to reduce the pressure from the first pressure to a second pressure while nipping the separated sheet between the first separating portion and the second separating portion.
1 Assignment
0 Petitions
Accused Products
Abstract
A shifting mechanism shifts at least one of a sheet accommodating portion and feeding portion, thereby changing a position of the feeding portion relative to sheets. A pressure changing mechanism changes pressure between first and second separating portions. A contact force controlling portion controls the shifting mechanism to provide a first contact force when the feeding portion starts a feeding operation, and controls the shifting mechanism, at a first timing, to reduce the contact force from the first contact force to a second contact force. A pressure controlling portion controls the pressure changing mechanism to provide a first pressure between the first and second separating portions when the feeding portion starts the feeding operation, and controls the pressure changing mechanism, at a second timing, to reduce the pressure from the first pressure to a second pressure while nipping the separated sheet between the first and second separating portions.
34 Citations
14 Claims
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1. A sheet supplying device comprising:
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a sheet accommodating portion that accommodates a plurality of sheets in a stacked arrangement;
a feeding portion disposed to be contactable with a topmost sheet of the plurality of sheets with contact force and rotatable in contact with the topmost sheet for conveying the topmost sheet downstream in a conveying direction;
a shifting mechanism that shifts at least one of the sheet accommodating portion and the feeding portion, thereby changing a position of the feeding portion relative to the plurality of sheets in the sheet accommodating portion;
a first separating portion disposed downstream of the feeding portion in the conveying direction;
a second separating portion disposed to be pressed against the first separating portion, the second separating portion being rotatable to separate the topmost sheet from other sheets of the plurality of sheets in cooperation with the first separating portion and to convey the separated sheet in the conveying direction;
a pressure changing mechanism that changes pressure between the first separating portion and the second separating portion;
a contact force controlling portion that controls the shifting mechanism to provide a first contact force when the feeding portion starts a feeding operation for conveying the topmost sheet in the conveying direction, and that controls the shifting mechanism, at a first timing, to reduce the contact force from the first contact force to a second contact force; and
a pressure controlling portion that controls the pressure changing mechanism to provide a first pressure between the first separating portion and the second separating portion when the feeding portion starts the feeding operation, and that controls the pressure changing mechanism, at a second timing, to reduce the pressure from the first pressure to a second pressure while nipping the separated sheet between the first separating portion and the second separating portion. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13)
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14. An image forming apparatus comprising:
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a sheet supplying device comprising;
a sheet accommodating portion that accommodates a plurality of sheets in a stacked arrangement;
a feeding portion disposed to be contactable with a topmost sheet of the plurality of sheets with contact force and rotatable in contact with the topmost sheet for conveying the topmost sheet downstream in a conveying direction;
a shifting mechanism that shifts at least one of the sheet accommodating portion and the feeding portion, thereby changing a position of the feeding portion relative to the plurality of sheets in the sheet accommodating portion;
a first separating portion disposed downstream of the feeding portion in the conveying direction;
a second separating portion disposed to be pressed against the first separating portion, the second separating portion being rotatable to separate the topmost sheet from other sheets of the plurality of sheets in cooperation with the first separating portion and to convey the separated sheet in the conveying direction;
a pressure changing mechanism that changes pressure between the first separating portion and the second separating portion;
a contact force controlling portion that controls the shifting mechanism to provide a first contact force when the feeding portion starts a feeding operation for conveying the topmost sheet in the conveying direction, and that controls the shifting mechanism, at a first timing, to reduce the contact force from the first contact force to a second contact force; and
a pressure controlling portion that controls the pressure changing mechanism to provide a first pressure between the first separating portion and the second separating portion when the feeding portion starts the feeding operation, and that controls the pressure changing mechanism, at a second timing, to reduce the pressure from the first pressure to a second pressure while nipping the separated sheet between the first separating portion and the second separating portion; and
an image forming unit that forms an image on the sheet supplied from the sheet supplying device.
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Specification