Medium conveying apparatus for correcting a skew of a medium

Patent metadata

Field	Value
Publication number	US-2022253013-A1
Application number	US-202217733829-A
Country	US
Kind code	A1
Filing date	Apr 29, 2022
Priority date	Dec 20, 2018
Publication date	Aug 11, 2022
Grant date	—

Abstract

A medium conveying apparatus includes a plurality of feed rollers spaced in a direction perpendicular to a medium conveying direction, each of the feed rollers rotating independently at a respective speed to feed a medium, a plurality of brake rollers, each of the plurality of brake rollers being located to face a corresponding one of the plurality of feed rollers, a plurality of torque limiters separately provided between one of rotation shafts of the plurality of brake rollers and a corresponding one of the plurality of brake rollers, and a processor to detect a skew of the medium, and correct the skew of the medium by changing the speed of one of the plurality of feed rollers when the skew of the medium is detected.

First claim

What is claimed is:

1 . A medium conveying apparatus comprising:
a feed roller to feed a medium; an imaging device to image the medium; and a processor to:
detect a skew of the medium, and
when the skew of the medium is detected, make an imaging range of the imaging device larger than an imaging range when skew of the medium is not occurring.

2 . The medium conveying apparatus according to claim 1 , wherein
the processor corrects the skew of the medium when the skew of the medium is detected, and wherein when skew correction of the medium fails, the processor makes an imaging range of the imaging device larger than an imaging range when skew of the medium is not occurring.

3 . The medium conveying apparatus according to claim 1 , wherein when the skew of the medium is detected, the processor makes an imaging range of the imaging device in the medium conveying direction larger than an imaging range when skew of the medium is not occurring.

4 . The medium conveying apparatus according to claim 1 , further comprising a first sensor and a second sensor spaced in the direction perpendicular to the medium conveying direction on a downstream side of the feed roller in the medium conveying direction, wherein
the processor detects the skew of the medium when the first sensor does not detect the medium within a predetermined time after the second sensor detects the medium.

5 . The medium conveying apparatus according to claim 1 , further comprising a third sensor
located between the feed roller and the imaging device, wherein
the processor causes the imaging device to start imaging at a timing when a front edge of the medium passes through the third sensor when skew of the medium is not occurring, and causes the imaging device to start imaging before the front edge of the medium passes through the third sensor when the skew of the medium is detected.

6 . The medium conveying apparatus according to claim 5 , wherein the processor causes the imaging device to start imaging immediately after determining failure of skew correction of the medium when the skew of the medium is detected.

7 . The medium conveying apparatus according to claim 1 , further comprising a third sensor located between the feed roller and the imaging device, wherein
the processor causes the imaging device to end imaging at a timing when a predetermined period elapses after a rear edge of the medium passes through the third sensor when skew of the medium is not occurring, and causes the imaging device to end imaging at a timing when a second predetermined period longer than the predetermined period elapses after the rear edge of the medium passes through the third sensor when the skew of the medium is detected.

8 . A method for imaging a medium, comprising:
feeding the medium by a feed roller; imaging the medium by an imaging device; detecting a skew of the medium; when the skew of the medium is detected, making an imaging range of the imaging device larger than an imaging range when skew of the medium is not occurring.

9 . The method according to claim 8 , wherein
the skew of the medium is corrected when the skew of the medium is detected, and wherein when skew correction of the medium fails, an imaging range of the imaging device is made larger than an imaging range when skew of the medium is not occurring.

10 . The method according to claim 8 , wherein
when the skew of the medium is detected, an imaging range of the imaging device in the medium conveying direction is made larger than an imaging range when skew of the medium is not occurring.

11 . The method according to claim 8 , wherein
the skew of the medium is detected when a first sensor does not detect the medium within a predetermined time after a second sensor detects the medium, in the detecting step, wherein the first sensor and the second sensor are spaced in the direction perpendicular to the medium conveying direction on a downstream side of the feed roller in the medium conveying direction.

12 . The method according to claim 8 , wherein the imaging device starts imaging at a timing when a front edge of the medium passes through a third sensor located between the feed roller and the imaging device when skew of the medium is not occurring, and the imaging device starts imaging before the front edge of the medium passes through the third sensor when the skew of the medium is detected.

13 . The method according to claim 12 , wherein the imaging device starts imaging immediately after determining failure of skew correction of the medium when the skew of the medium is detected.

14 . The method according to claim 8 , wherein the imaging device ends imaging at a timing when a predetermined period elapses after a rear edge of the medium passes through a third sensor located between the feed roller and the imaging device when skew of the medium is not occurring, and the imaging device ends imaging at a timing when a second predetermined period longer than the predetermined period elapses after the rear edge of the medium passes through the third sensor when the skew of the medium is detected.

15 . A medium conveying apparatus comprising:
a feed roller to feed a medium; an imaging device to image the medium; and a processor to:
detect a skew of the medium, and
when the skew of the medium is detected, change an imaging range of the imaging device.

16 . The medium conveying apparatus according to claim 15 , wherein
the processor corrects the skew of the medium when the skew of the medium is detected, and wherein when skew correction of the medium fails, the processor changes an imaging range of the imaging device.

17 . The medium conveying apparatus according to claim 15 , wherein when the skew of the medium is detected, the processor changes an imaging range of the imaging device in the medium conveying direction.

18 . The medium conveying apparatus according to claim 15 , further comprising a first sensor and a second sensor spaced in the direction perpendicular to the medium conveying direction on a downstream side of the feed roller in the medium conveying direction, wherein
the processor detects the skew of the medium when the first sensor does not detect the medium within a predetermined time after the second sensor detects the medium.

Assignees

• Pfu Ltd

Inventors

• Umi Takayuki
• Okano Shigeharu

Classifications

• G03G15/6567 Primary

  for deskewing or aligning · CPC title

• G03G2215/00746

  of sheet velocity · CPC title

• B65H2220/02

  indicating an entity which is controlled, adjusted or changed by a control process, i.e. output · CPC title

• H04N1/00718

  Skew · CPC title

• H04N1/00745

  Detecting the leading or trailing ends of a moving sheet · CPC title