Sheet discharge apparatus and image forming apparatus

Patent metadata

Field	Value
Publication number	US-11180337-B2
Application number	US-201916413748-A
Country	US
Kind code	B2
Filing date	May 16, 2019
Priority date	May 31, 2018
Publication date	Nov 23, 2021
Grant date	Nov 23, 2021

Abstract

A sheet discharge apparatus includes a pivot member pivoting in an up-down direction by being pressed by a sheet discharged from a sheet discharging portion, with the pivot member retained by being in contact with an uppermost sheet supported on the sheet supporting portion. A control unit changes a sheet interval between a preceding sheet and a succeeding sheet and executes a first discharge operation in which at least one sheet is discharged, and a second discharge operation in which sheets are discharged by the sheet discharging portion at a first sheet interval such that the pivot member does not contact with an uppermost sheet supported on the sheet supporting portion during the second discharge operation, and the control unit acquires a number of sheets to be discharged in the second discharge operation based on a detected position of the pivot member detected during the first discharge operation.

First claim

What is claimed is:

1. A sheet discharge apparatus comprising:
a sheet discharging portion configured to discharge a sheet;
a sheet supporting portion configured to support the sheet discharged from the sheet discharging portion;
a pivot member configured to pivot in an up-down direction around a pivot axis by being pressed by the sheet discharged from the sheet discharging portion, the pivot member retained by being in contact with an uppermost sheet supported on the sheet supporting portion;
a detecting unit configured to detect a position of the pivot member; and
a control unit configured to change a sheet interval which is an interval between a preceding sheet and a succeeding sheet,
wherein, in a state where a job in which a plurality of sheets are to be continuously discharged is received, the control unit executes a first discharge operation in which at least one sheet is discharged by the sheet discharging portion, and a second discharge operation in which sheets are discharged by the sheet discharging portion at a first sheet interval such that the pivot member does not contact with an uppermost sheet supported on the sheet supporting portion during the second discharge operation, and
the control unit is configured to acquire a number of sheets to be discharged in the second discharge operation based on a detection result of the detecting unit detected during the first discharge operation.

2. The sheet discharge apparatus according to claim 1 , wherein the control unit executes a third discharge operation in which at least one sheet is discharged by the sheet discharge portion at a second sheet interval that is longer than the first sheet interval, and a fourth discharge operation in which the sheet is discharged by the sheet discharging portion at a sheet interval that is shorter than the second sheet interval, and
the control unit is configured to acquire a number of sheets to be discharged in the fourth discharge operation based on a detection result of the detecting unit detected during the third discharge operation.

3. The sheet discharge apparatus according to claim 2 , wherein in the fourth discharge operation, the control unit controls the sheet discharging portion so as to discharge sheets at the first sheet interval.

4. The sheet discharge apparatus according to claim 1 , wherein in the first discharge operation, the control unit calculates a number of sheets to be discharged in the second discharge operation based on the detection result of the detecting unit during discharge of a first sheet of the job.

5. The sheet discharge apparatus according to claim 2 , wherein the detecting unit comprises a pivotal quantity detecting portion configured to detect a pivotal quantity of the pivot member and a target position detecting portion configured to detect that the pivot member is positioned at a target position, the detecting unit detecting the pivot angle of the pivot member pivoting between a position where the pivot member is retained in contact with the uppermost sheet and the target position.

6. The sheet discharge apparatus according to claim 5 , wherein the target position detecting portion detects that the pivot member is positioned at a predetermined pivot range, and
the target position is a position in which the target position detecting portion starts detecting the pivot member.

7. The sheet discharge apparatus according to claim 6 , wherein in a case where the sheet discharging portion continuously discharges sheets in each of the second discharge operation and the fourth discharge operation, the control unit stops the sheet discharging portion if the target position detecting portion detects that the pivot member has pivoted beyond the predetermined pivot range.

8. The sheet discharge apparatus according to claim 6 , wherein in the third discharge operation, the pivot member pivots to a position beyond the predetermined pivot range.

9. The sheet discharge apparatus according to claim 6 , wherein the pivot member comprises a first end portion that contacts the uppermost sheet and a second end portion that is arranged on an opposite side of the first end portion interposing the pivot axis, and
the target position detecting portion detects that the second end portion of the pivot member is positioned within a predetermined pivot range.

10. The sheet discharge apparatus according to claim 5 , wherein the pivotal quantity detecting portion comprises a pivot disk configured to pivot around the pivot axis integrally with the pivot member and comprising a plurality of slits along a pivoting direction, a light emitting element configured to emit light, and a photosensing element configured to receive light that is emitted from the light emitting element and that has passed through any one of the plurality of slits, the pivotal quantity detecting portion outputting a pulse signal based on an on state or an off state of the photosensing element.

11. The sheet discharge apparatus according to claim 10 , wherein the photosensing element comprises a first photosensing element and a second photosensing element which are configured to output pulse signals based on the pivotal quantity of the pivot member, the pulse signals output by the first photosensing element and the second photosensing element having mutually different periodicity or different phase.

12. The sheet discharge apparatus according to claim 11 , wherein the plurality of slits comprises a first row of slits and a second row of slits that are arranged at different positions in a radial direction of the pivot disk,
the first photosensing element receives light having passed through any one of slits of the first row, and
the second photosensing element receives light having passed through any one of slits of the second row.

13. The sheet discharge apparatus according to claim 10 , wherein the pivot disk comprises a wide slit having a longer width in the pivoting direction than the plurality of slits, and
the target position detecting portion comprises a third light emitting element that emits light and a third photosensing element that receives the light emitted from the third light emitting element and passed through the wide slit.

14. An image forming apparatus comprising:
an image forming unit configured to form an image on a sheet;
a sheet discharging portion configured to discharge the sheet on which the image has been formed in the image forming unit;
a sheet supporting portion configured to support the sheet discharged from the sheet discharging portion;
a pivot member configured to pivot in an up-down direction around a pivot axis by being pressed by the sheet discharged from the sheet discharging portion, the pivot member retained by being in contact with an uppermost sheet supported on the sheet supporting portion;
a detecting unit configured to detect a position of the pivot member; and
a control unit configured to change a sheet interval which is an interval between a preceding sheet and a succeeding sheet,
wherein, in a state where a job in which a plurality of sheets are to be continuously discharged is received, the control unit executes a first discharge operation in which at least one sheet is discharged by the sheet discharging portion, and a second discharge operation in which sheets are discharged by the sheet discharging portion at a first sheet interval such that the pivot member does not contact with an uppermost sheet supported on the sheet supporting portion during the second discharge operation, and
the control unit is configured to acquire a number of sheets to be discharged in the second discharge operation based on a d

Assignees

• Canon Kk

Inventors

• Kaiga Miho
• Suzuki Yohei
• Ochi Junichi
• Okuno Kazuhide

Classifications

• B65H2553/61

  Mechanical means, e.g. contact arms · CPC title

• B65H29/14

  and introducing into a pile · CPC title

• B65H2301/4452

  Regulating space between separated articles · CPC title

• B65H2511/22

  Distance · CPC title

• B65H43/08

  Photoelectric devices · CPC title