Sheet conveying device and image forming system

Abstract

A sheet conveying device connected between image forming device and post-processing device of which sheet conveying speed is higher than that of image forming device. The sheet conveying device includes: feed-in roller for feeding in a sheet ejected from image forming device; conveying roller for conveying the sheet; ejection roller for ejecting the sheet to post-processing device; conveying path from feed-in roller to ejection roller; and controller for controlling sheet conveying speeds of the rollers, wherein the controller performs control such that: when sheet conveying device feeds in the sheet ejected from image forming device, the conveying speeds of the rollers are the same as conveying speed at which image forming device ejects the sheet; and when image forming device has completed ejection of a trailing edge of the sheet, the conveying speeds of the rollers are the same as conveying speed at which post-processing device feeds in the sheet.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic structural diagram of image forming system 1 in an embodiment of the invention;

FIG. 2 is a block diagram showing functional constitutions of image forming device 100, sheet conveying device 200 and post-processing device 300 of the image forming system 1;

FIG. 3 is a flow chart showing processing at the time of power-on carried out by sheet conveying device 200; and

FIG. 4 is a flow chart showing processing carried out by sheet conveying device 200, during image forming operation.

Claims

1. A sheet conveying device connected between an image forming device for forming an image and a post-processing device of which sheet conveying speed is higher than a sheet conveying speed of the image forming device, the sheet conveying device comprising: a feed-in roller for feeding in a sheet ejected from the image forming device;a conveying roller for conveying the sheet;an ejection roller for ejecting the sheet to the post-processing device;a conveying path from the feed-in roller to the ejection roller; anda controller for controlling sheet conveying speeds of the feed-in roller, conveying roller, and ejection roller,wherein the controller performs control such that:when the sheet conveying device feeds in the sheet ejected from the image forming device, the conveying speeds of the feed-in roller, conveying roller, and ejection roller are the same as a conveying speed at which the image forming device ejects the sheet; andwhen the image forming device has completed ejection of a trailing edge of the sheet, the conveying speeds of the feed-in roller, conveying roller, and ejection roller are the same as a conveying speed at which the post-processing device feeds in the sheet.

2. The sheet conveying device of claim 1, wherein a length of the conveying path is longer than a length of a maximum sheet size processable by the image forming device and the post-processing device, the length being along a conveying direction.

3. The sheet conveying device of claim 2, wherein the conveying path is flex.

4. The sheet conveying device of claim 1, wherein the conveying path is longer than a linear distance from the conveying roller to the ejection roller.

5. The sheet conveying device of claim 1, further comprising: a second receiving section for receiving, from the post-processing device, feed-in conveying speed information indicating the conveying speed at which the post-processing device feeds in the sheet; anda first receiving section for receiving, from the image forming device, ejection conveying speed information indicating the conveying speed at which the image forming device ejects the sheet.

6. An image forming system, comprising: an image forming device for forming an image;a post-processing device of which sheet conveying speed is higher than a sheet conveying speed of the image forming device; anda sheet-conveying device, connected between the image forming device and post-processing device, for feeding in a sheet ejected from the image forming device and ejecting the sheet to the post-processing device, the sheet-conveying device including:a feed-in roller for feeding in a sheet ejected from the image forming device;a conveying roller for conveying the sheet;an ejection roller for ejecting the sheet to the post-processing device;a conveying path from the feed-in roller to the ejection roller; anda controller for controlling sheet conveying speeds of the feed-in roller, conveying roller, and ejection roller,wherein the controller performs control such that:when the sheet conveying device feeds in the sheet ejected from the image forming device, the conveying speeds of the feed-in roller, conveying roller, and ejection roller are the same as a conveying speed at which the image forming device ejects the sheet; andwhen the image forming device has completed ejection of a trailing edge of the sheet, the conveying speeds of the feed-in roller, conveying roller, and ejection roller are the same as a conveying speed at which the post-processing device feeds in the sheet.

7. The image forming system of claim 6, wherein a length of the conveying path is longer than a length of a maximum sheet size processable by the image forming device and the post-processing device, the length being along a conveying direction.

8. The image forming system of claim 7, wherein the conveying path is flex.

9. The image forming system of claim 6, wherein the conveying path is longer than a linear distance from the conveying roller to the ejection roller.

10. The image forming system of claim 6, wherein the sheet conveying device further includes: a second receiving section for receiving, from the post-processing device, feed-in conveying speed information indicating the conveying speed at which the post-processing device feeds in the sheet; anda first receiving section for receiving, from the image forming device, ejection conveying speed information indicating the conveying speed at which the image forming device ejects the sheet.