Sheet processing apparatus with control of sheet conveyance based on skew amount, control method, image forming apparatus, and storage medium

• US 6,353,726 B1
• Filed: 07/05/2000
• Issued: 03/05/2002
• Est. Priority Date: 07/21/1999
• Status: Expired due to Term

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Murata, Mitsushige, Okamoto, Kiyoshi, Miyake, Norifumi
• Primary Examiner(s): Chen, Sophia S.
• Assistant Examiner(s): NGO, HOANG X
• Application Number:
  US09/610,375
• Time in Patent Office: 608 Days
• Field of Search: 271/37, 271/58.08, 271/188, 271/298, 399/16, 399/18, 399/394, 399/395, 399/396, 399/407, 399/408, 399/410
• US Class Current: 399/407
• CPC Class Codes: B65H 2220/01 indicating an entity as a function of which control, adjustment or change is performed, i.e. input
• CPC Class Codes: B65H 2220/02 indicating an entity which is controlled, adjusted or changed by a control process, i.e. output
• CPC Class Codes: B65H 2511/24 Irregularities, e.g. in orientation or skewness
• CPC Class Codes: B65H 2513/40 Movement
• CPC Class Codes: B65H 2513/51 Sequence of process
• CPC Class Codes: B65H 7/00 Controlling article feeding, separating, pile-advancing, or associated apparatus, to take account of incorrect feeding, absence of articles, or presence of faulty articles
• CPC Class Codes: G03G 15/6541 Binding sets of sheets, e.g. by stapling, glueing
• CPC Class Codes: G03G 15/6582 Special processing for irreversibly adding or changing the sheet copy material characteristics or its appearance, e.g. stamping, annotation printing, punching

Abstract

Conveyance of a sheet is controlled based on a detected skew amount of a conveyed sheet and a result of determination on whether an operation mode set through an operation console is a punching mode or not, thus protecting a user from spending extra time and efforts and extra cost in the event that a sheet skews.

Claims

1. A sheet processing apparatus comprising:

a first stacking tray connectable to an image forming apparatus and on which sheets are stacked;

a conveyor for conveying a sheet loaded on said first stacking tray and a sheet on which an image has been formed by said image forming apparatus; and

a second stacking tray for stacking the sheets conveyed from said first stacking tray and the sheet on which an image has been formed by said image forming apparatus;

wherein sheet processing is performed on the sheet conveyed by said conveyor from said first stacking tray, according to an operation mode of said image forming apparatus,

said sheet processing apparatus comprising;

detecting means for detecting a skew amount of a sheet conveyed from said first stacking tray;

determining means for determining whether to perform sheet processing by said sheet processing apparatus; and

control means for controlling conveyance of the sheet by said conveyor based on a skew amount of the sheet detected by said detecting means and a determination result of said determining means,

wherein said control means inhibits conveyance of a sheet by said conveyor if a detected skew amount of a sheet detected exceeds a first predetermined skew amount and said determining means determines to perform said sheet processing, and permits conveyance of a sheet by said conveyor if the detected skew amount of the sheet exceeds the first predetermined skew amount and said determining means determines not to perform said sheet processing.

2. A sheet processing apparatus according to claim 1, wherein said control means inhibits conveyance of a sheet by said conveyor if a skew amount of a sheet detected by said detecting means exceeds a second predetermined skew amount, which is larger than the first predetermined skew amount, and permits conveyance of the sheet by said conveyor if the skew amount of the sheet detected by said detecting means is not more than the first predetermined skew amount.

3. A sheet processing apparatus according to claim 1, wherein said control means informs said image forming apparatus whenever it inhibits conveyance of a sheet by said conveyor.

4. A sheet processing apparatus according to claim 1, wherein the sheet processing performed is punching.

5. A control method for a sheet processing apparatus comprising a first stacking tray connectable to an image forming apparatus and on which sheets are stacked, a conveyor for conveying a sheet loaded on said first stacking tray and a sheet on which an image has been formed by said image forming apparatus, wherein sheet processing is performed on the sheet conveyed by said conveyor from said first stacking tray, according to an operation mode of said image forming apparatus, said control method comprising the steps of:

detecting a skew amount of a sheet conveyed from said first stacking tray;

determining whether to perform sheet processing by said sheet processing apparatus; and

controlling conveyance of the sheet by said conveyor based on a skew amount of the sheet detected in said detecting step and a determination result of said determining step,

wherein said control method inhibits conveyance of a sheet by said conveyor if a detected skew amount of a sheet exceeds a first predetermined skew amount and said determining step determines to perform said sheet processing, and permits conveyance of a sheet by said conveyor if the detected skew amount of the sheet exceeds the first predetermined skew amount and said determining step determines not to perform said sheet processing.

6. An image forming apparatus comprising:

image forming means for forming an image on a sheet based on input data;

a first stacking tray on which a sheet is loaded;

conveyor for conveying the sheet loaded on said first stacking tray and a sheet on which an image has been formed by said image forming means;

a second stacking tray for stacking the sheets conveyed from said first stacking tray and the sheet on which an image has been formed by said image forming means,

wherein sheet processing is performed on the sheet conveyed by said conveyor from said first stacking tray, according to an operation mode of said image forming apparatus,

said image forming apparatus comprising;

detecting means for detecting a skew amount of the sheet conveyed from said first stacking tray;

determining means for determining whether to perform sheet processing by said image forming apparatus; and

control means for controlling conveyance of the sheet by said conveyor based on a skew amount of the sheet detected by said detecting means and a determination result of said determining means,

wherein said control means inhibits conveyance of a sheet by said conveyor if a skew amount of a sheet detected by said detecting means exceeds a first predetermined skew amount and said determining means determines to perform said sheet processing, and permits conveyance of a sheet by said conveyor if the skew amount of the sheet detected by said detecting means exceeds the first predetermined skew amount and said determining means determines not to perform said sheet processing.

7. A sheet processing apparatus for implementing sheet processing to a sheet, comprising:

conveyor for conveying a sheet for processing; and

control means for inhibiting operation of said conveyor based on a skew amount of the sheet conveyed by said conveyor,

wherein said control means permits the operation of said conveyor if the skew amount of the sheet conveyed by said conveyor is a skew amount lower than an amount that will cause sheet conveyance failure; and

said control means inhibits the operation of said conveyor if the sheet is a sheet for a job involving sheet processing, and permits the operation of said conveyor if the sheet is a sheet for a job in which sheet processing is not performed when the skew amount of the sheet conveyed by said conveyor is the skew amount lower than the amount that will cause sheet conveyance failure.

8. A sheet processing apparatus according to claim 7, wherein said apparatus selectively performs a plurality of types of sheet processing that are different from one another, and

wherein said control means permits the operation of said conveyor, depending on a type of sheet processing to be performed, rather than inhibiting the operation of said conveyor even if the sheet is a sheet for the job involving sheet processing, when the skew amount of the sheet conveyed by said conveyor is the skew amount lower than the amount that will cause sheet conveyance failure.

9. An apparatus according to claim 8, further comprising:

aligning means for aligning a sheet conveyed by said conveyor;

wherein said control means permits the operation of said conveyor if a type of sheet processing to be performed is one that is performed after alignment by said aligning means.

10. An apparatus according to claim 9, wherein said control means inhibits the operation of said conveyor if the type of sheet processing to be performed is one that is performed without the alignment by said aligning means.

11. An apparatus according to claim 10, wherein the sheet processing performed after the alignment by said aligning means includes binding, and the sheet processing performed without performing the alignment by said aligning means includes punching of a sheet.

12. An apparatus according to claim 8, wherein

one of said plurality of types of sheet processing is punching of a sheet;

and

said control means inhibits the operation of said conveyor if the sheet is a sheet for a punching job, and permits the operation of said conveyor if the sheet is a sheet for a job other than a punching job when the skew amount of the sheet conveyed by said conveyor is a skew amount lower than an amount that will cause sheet conveyance failure.

13. A sheet processing apparatus according to claim 7, further comprising:

a stacking tray on which sheets are loaded;

wherein said conveyor conveys the sheet loaded on said stacking tray; and

said control means inhibits the operation of said conveyor so as to prevent at least the sheet loaded on said stacking tray from being conveyed.

14. A sheet processing apparatus according to claim 7, wherein

said sheet processing apparatus is connectable to an image forming apparatus;

and

said control means inhibits the operation of said conveyor to prevent conveying of a sheet from said image forming apparatus to said sheet processing apparatus.

15. A sheet processing apparatus according to claim 7, further comprising notifying means for informing an operator in the event that the operation of said conveyor has been inhibited.

16. A control method for a sheet processing apparatus having a conveyor for conveying a sheet and for performing sheet processing to the sheet conveyed by said conveyor, comprising the steps of:

inhibiting an operation of said conveyor based on a skew amount of the sheet conveyed by said conveyor;

permitting the operation of said conveyor if the skew amount of the sheet conveyed by said conveyor is a skew amount lower than the amount that will cause sheet conveyance failure; and

inhibiting the operation of said conveyor if the sheet is a sheet for a job involving sheet processing, or permitting the operation of said conveyor if the sheet is a sheet for a job in which sheet processing is not performed when the skew amount of the sheet conveyed by said conveyor is the skew amount lower than the amount that will cause sheet conveyance failure.

17. A computer-readable storage medium storing a program for causing a sheet processing apparatus, which has a conveyor for conveying a sheet and for performing sheet processing to the sheet conveyed by said conveyor to implement the steps of:

inhibiting an operation of said conveyor based on a skew amount of the sheet conveyed by said conveyor;

permitting the operation of said conveyor if the skew amount of the sheet conveyed by said conveyor is a skew amount lower than the amount that will cause sheet conveyance failure; and

inhibiting the operation of said conveyor if the sheet is a sheet for a job involving sheet processing, and permitting the operation of said conveyor if the sheet is a sheet for a job in which sheet processing is not performed when the skew amount of the sheet conveyed by said conveyor is the skew amount lower than the amount that will cause sheet conveyance failure.

18. A sheet processing apparatus for performing sheet processing to a sheet, comprising:

a conveyor for conveying a sheet;

aligning means for aligning a sheet conveyed by said conveyor; and

control means for inhibiting sheet processing on the sheet based on a skew amount of the sheet conveyed by said conveyor;

wherein said control means permits implementation of sheet processing to the sheet if the skew amount of the sheet conveyed by said conveyor is a skew amount lower than the amount that will cause sheet conveyance failure and if the sheet is a sheet for a job involving sheet processing performed after the alignment by said aligning means is performed, or inhibits implementation of the sheet processing on the sheet if the skew amount of the sheet conveyed by said conveyor is a skew amount lower than the amount that will cause sheet conveyance failure and if the sheet is a sheet for a job involving sheet processing performed without implementing the alignment by said aligning means.

19. A control method for a sheet processing apparatus which has conveyor for conveying a sheet, aligning means for aligning a sheet conveyed by said conveyor, and processing means for performing sheet processing on the sheet, comprising the steps of:

inhibiting sheet processing on the sheet based on a skew amount of the sheet conveyed by said conveyor;

permitting implementation of the sheet processing on the sheet if the skew amount of the sheet conveyed by said conveyor is a skew amount lower than the amount that will cause sheet conveyance failure and if the sheet is a sheet for a job involving sheet processing performed after the alignment by said aligning means is performed; and

inhibiting implementation of the sheet processing on the sheet if the skew amount of the sheet conveyed by said conveyor is a skew amount lower than the amount that will cause sheet conveyance failure and if the sheet is a sheet for a job involving sheet processing performed without implementing the alignment by said aligning means.

20. A computer-readable storage medium storing a program for causing a sheet processing apparatus, which has conveyor for conveying a sheet, aligning means for aligning the sheet conveyed by said conveyor and processing means for performing sheet processing to the sheet conveyed from said conveyor, to implement the steps of:

inhibiting sheet processing on the sheet based on a skew amount of the sheet conveyed by said conveyor;

performing sheet processing on the sheet if the skew amount of the sheet conveyed by said conveyor is a skew amount lower than the amount that will cause sheet conveyance failure and if the sheet is a sheet for a job involving sheet processing performed after the alignment by said aligning means is performed; and

inhibiting implementation of sheet processing on the sheet if the skew amount of the sheet conveyed by said conveyor is a skew amount lower than the amount that will cause sheet conveyance failure and if the sheet is a sheet for a job involving sheet processing performed without performing the alignment by said aligning means.