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US 2022/0063943 A1Published application
Sheet feeding device and image forming apparatus
AssigneeCanon Kabushiki Kaisha
InventorYuma Inui
Life of this patent
Estimating the term…
Abstract
A sheet feeding device includes a first feeding roller pair, an upstream feeding roller pair, a downstream feeding roller pair, a second feeding roller pair, a first detecting portion, a second detecting portion, a third detecting portion, and a controller. The controller calculates a sheet feeding speed on the basis of a first time and a first distance. The controller calculates a length of the sheet with respect to the sheet feeding direction on the basis of the sheet feeding speed, a second time, and a second distance. The controller controls a sheet feeding timing by the second feeding roller pair on the basis of information of the length of the sheet.
Claims12
A sheet feeding device comprising:
- a first feeding roller pair rotatable in a sheet nipping state and configured to feed a sheet;
- an upstream feeding roller pair provided upstream of said first feeding roller pair with respect to a sheet feeding direction and configured to feed the sheet;
- a downstream feeding roller pair provided downstream of said first feeding roller pair with respect to the sheet feeding direction and configured to feed the sheet;
- a second feeding roller pair provided downstream of said downstream feeding roller pair with respect to the sheet feeding direction and configured to feed the sheet;
- a first detecting portion provided at a first detecting position downstream of said first feeding roller pair and upstream of said downstream feeding roller pair with respect to the sheet feeding direction and configured to detect passing of a leading end portion of the sheet fed by said first feeding roller pair;
- a second detecting portion provided at a second detecting position, different from the first detecting position, downstream of said first feeding roller pair and upstream of said downstream feeding roller pair with respect to the sheet feeding direction and configured to detect the passing of the leading end portion of the sheet fed by said first feeding roller pair;
- a third detecting portion provided at a third detecting position upstream of said first feeding roller pair and downstream of said upstream feeding roller pair with respect to the sheet feeding direction and configured to detect passing of a trailing end portion of the sheet fed by said first feeding roller pair;
- and
- a controller configured to perform calculation in response to signals from said first detecting portion, said second detecting portion, and said third detecting portion,
- wherein said controller calculates a sheet feeding speed on the basis of a first time which is a difference between a timing when the leading end portion of the sheet passes through the first detecting position and a timing when the leading end portion of the sheet passes through the second detecting position and a first distance between the first detecting position and the second detecting position with respect to the sheet feeding direction,
- wherein said controller calculates a length of the sheet with respect to the sheet feeding direction on the basis of the sheet feeding speed, a second time which is a difference between a timing when the leading end portion of the sheet passes through the second detecting position and a timing when the trailing end of the sheet passes through the third detecting position, and a second distance between the second detecting position and the third detecting position with respect to the sheet feeding direction, and
- wherein said controller controls a sheet feeding timing by said second feeding roller pair on the basis of information of the length of the sheet.
9 more elements
A sheet feeding device comprising:
- a first feeding roller pair rotatable in a sheet nipping state and configured to feed a sheet;
- an upstream feeding roller pair provided upstream of said first feeding roller pair with respect to a sheet feeding direction and configured to feed the sheet;
- a downstream feeding roller pair provided downstream of said first feeding roller pair with respect to the sheet feeding direction and configured to feed the sheet;
- a second feeding roller pair provided downstream of said downstream feeding roller pair with respect to the sheet feeding direction and configured to feed the sheet;
- a first detecting portion provided at a first detecting position upstream of said first feeding roller pair and downstream of said upstream feeding roller pair with respect to the sheet feeding direction and configured to detect passing of a trailing end portion of the sheet fed by said first feeding roller pair;
- a second detecting portion provided at a second detecting position, different from the first detecting position, upstream of said first feeding roller pair and downstream of said downstream feeding roller pair with respect to the sheet feeding direction and configured to detect the passing of the trailing end portion of the sheet fed by said first feeding roller pair;
- a third detecting portion provided at a third detecting position downstream of said first feeding roller pair and upstream of said upstream feeding roller pair with respect to the sheet feeding direction and configured to detect passing of a leading end portion of the sheet fed by said first feeding roller pair;
- and
- a controller configured to perform calculation in response to signals from said first detecting portion, said second detecting portion, and said third detecting portion,
- wherein when the leading end portion of the sheet fed by said first feeding roller pair is detected by said third detecting portion, the trailing end portion of the sheet passes through said upstream feeding roller pair, and
- wherein when the trailing end portion of the sheet fed by said first feeding roller pair is detected by said first detecting portion and said second detecting position, the leading end portion does not reach said downstream feeding roller pair,
- wherein said controller calculates a sheet feeding speed on the basis of a first time which is a difference between a timing when the trailing end portion of the sheet passes through the first detecting position and a timing when the trailing end portion of the sheet passes through the second detecting position and a first distance between the first detecting position and the third detecting position with respect to the sheet feeding direction,
- wherein said controller calculates a length of the sheet with respect to the sheet feeding direction on the basis of the sheet feeding speed, a second time which is a difference between a timing when the leading end portion of the sheet passes through the third detecting position and a timing when the trailing end of the sheet passes through the second detecting position, and a second distance between the second detecting position and the third detecting position with respect to the sheet feeding direction, and
- wherein said controller controls a sheet feeding timing by said second feeding roller pair on the basis of information of the length of the sheet.
11 more elements
A sheet feeding device comprising:
- a first feeding roller pair rotatable in a sheet nipping state and configured to feed a sheet;
- an upstream feeding roller pair provided upstream of said first feeding roller pair with respect to a sheet feeding direction and configured to feed the sheet;
- a downstream feeding roller pair provided downstream of said first feeding roller pair with respect to the sheet feeding direction and configured to feed the sheet;
- a second feeding roller pair provided downstream of said downstream feeding roller pair with respect to the sheet feeding direction and configured to feed the sheet;
- a first reading portion provided so as to extend along the sheet feeding direction on a side downstream of said first feeding roller pair and upstream of said downstream feeding roller pair with respect to the sheet feeding direction and configured to read an image of a leading end portion of the sheet fed by said first feeding roller pair;
- a second reading portion provided so as to extend along the sheet feeding direction on a side upstream of said first feeding roller pair and downstream of said upstream feeding roller pair with respect to the sheet feeding direction and configured to read an image of the trailing end portion of the sheet fed by said first feeding roller pair;
- and
- a controller configured to perform calculation depending on the images read by said first reading portion and said second reading portion,
- wherein when the image of the leading end portion of the sheet fed by said first feeding roller pair is read by said first reading portion, the trailing end portion of the sheet passes through said upstream feeding roller pair, and
- wherein when the image of the trailing end of the sheet fed by said first feeding roller pair is read by said second reading portion, the leading end portion does not reach said downstream feeding roller pair,
- wherein said controller calculates a sheet feeding speed on the basis of a fifth time which is a difference in timing between a plurality of images read by said first reading portion and a fifth distance which is a difference in position of the leading end portion of the sheet between the plurality of images,
- wherein said controller calculates a length of the sheet on the basis of a sixth time which is a difference in timing between the image read by said first reading portion and the image read by said second reading portion, and
- wherein said controller controls a sheet feeding timing by said second feeding roller pair on the basis of information of the length of the sheet.
10 more elements
Dependencies are inferred from the claim text.