Image reading apparatus having first motor for rotating feed roller, and second motor for rotating conveyance roller and reverse roller

Patent metadata

Field	Value
Publication number	US-2017050812-A1
Application number	US-201615232078-A
Country	US
Kind code	A1
Filing date	Aug 9, 2016
Priority date	Aug 17, 2015
Publication date	Feb 23, 2017
Grant date	—

Abstract

In an image reading apparatus, in a first process, first and second motor rotate feed and conveyance rollers with circumferential speeds of first and second speeds, respectively. In the first process, the reverse roller has a first separation performance for separating a sheet from another sheet. In a second process, after a detector detects a leading edge of the sheet, the controller stops the first motor, and decelerates the second motor, and the reverse roller has a second separation performance lower than the first separation performance. In a third process, after a trailing edge of the sheet reaches a specific position, the first motor starts rotating the feed roller with the circumferential speed of the first speed. In a fourth process, after the trailing edge of the sheet passes through a reading end position, the controller accelerates the second motor.

First claim

What is claimed is:

1 . An image reading apparatus comprising:
a first motor; a second motor; a feed roller configured to rotate in a rotational direction by torque generated by the first motor so as to convey a sheet to in a conveyance direction; a reverse roller configured to be in peripheral contact with the feed roller, and configured to rotate in the rotational direction by torque received from the second motor via a torque limiter; a conveyance roller disposed downstream of the feed roller in the conveyance direction, and configured to rotate in the rotational direction by torque from the second motor so as to convey the sheet from the feed roller in the conveyance direction, a circumferential speed of the conveyance roller varying depending on a circumferential speed of the reverse roller; a reader disposed downstream of the conveyance roller in the conveyance direction and configured to read an image on the sheet at a reading position; a detector disposed between the conveyance roller and the reading position in the conveyance direction and configured to detect the sheet; and a controller comprising hardware configured to perform processes comprising: a first drive process in which the controller is configured to control the first motor and the second motor to rotate the feed roller with the circumferential speed of a first speed and the conveyance roller with the circumferential speed of a second speed, wherein the reverse roller is configured to be rotated with the circumferential speed of a third speed in the first drive process so that the reverse roller has a first separation performance for separating a sheet from other sheets, which are in an overlapped state, together with the feed roller with the circumferential speed of the first speed, wherein the feed roller conveys a specific sheet in the conveyance direction through the first drive process; a second drive process in which, in response to detection of a leading edge of the specific sheet by the detector after performing the first drive process, the controller is configured to stop the first motor, and to decelerate the second motor to rotate the conveyance roller with the circumferential speed of a fourth speed slower than both the first speed and the second speed, wherein when the circumferential speed of the conveyance roller is the fourth speed in the second drive process, the reverse roller is configured to be rotated with the circumferential speed of a fifth speed so that the reverse roller has a second separation performance for separating a sheet from other sheets which are in an overlapped state, wherein the fifth speed is slower than the third speed and the second separation performance is lower than the first separation performance, wherein the conveyance roller conveys the specific sheet through the second drive process; a third drive process in which, in response to conveying the specific sheet through the second drive process so that a trailing edge of the specific sheet reaches a first position after the detector detects the trailing edge of the specific sheet, the controller is configured to control the first motor to start rotating the feed roller with the circumferential speed of the first speed, wherein the first position is located between the detector and the reading position, and the first position is separated from the detector by a prescribed distance; and a fourth process in which, in response to passage of the trailing edge of the specific sheet through a reading end position after performing the third drive process, the controller is configured to accelerate the second motor to rotate the conveyance roller with the circumferential speed of the second speed while the circumferential speed of the feed roller is maintained to the first speed, the reading end position being downstream of the first position in the conveyance direction.

2 . The image reading apparatus according to claim 1 , wherein the processes further comprise a reading process in which the controller controls the reader to start reading the image of the specific sheet after the second motor is decelerated through the second drive process.

3 . The image reading apparatus according to claim 2 , wherein the second drive process includes:
a first stop process in which the controller stops both the first motor and the second motor when the detector detects the leading edge of the specific sheet that is conveyed while the first motor and the second motor rotate; and a first acceleration process in which the controller controls the second motor, which is stopped through the first stop process, to start rotating the conveyance roller with the circumferential speed of the fourth speed, wherein in the reading process the reader starts reading the image of the specific sheet after the circumferential speed of the conveyance roller is the fourth speed through the first acceleration process.

4 . The image reading apparatus according to claim 2 , wherein the processes further comprise a reading end process in which, in response to passage of the trailing edge of the specific sheet through the reading end position, the controller controls the reader to finish reading the image of the specific sheet before the second motor is accelerated through the fourth drive process.

5 . The image reading apparatus according to claim 4 , wherein the fourth drive process includes:
a second stop process in which the controller stops the second motor after the reader finishes reading the image of the specific sheet through the reading end process; and a second acceleration process in which the controller controls the second motor, which is stopped through the second stop process, to start rotating the conveyance roller with the circumferential speed of the second speed.

6 . The image reading apparatus according to claim 1 ,
wherein the reader comprises:
a first reader configured to read an image on one side of the sheet at a first reading portion, the first position being positioned between the detector and the first reading portion in the conveyance direction; and
a second reader configured to read an image on the other side of the sheet at a second reading portion downstream of the first reading position in the conveyance direction, the reading end position being positioned downstream of the second reading portion in the conveyance direction.

7 . A method comprising:
a first drive step to control a first motor and a second motor of an image reading apparatus to rotate a feed roller with the circumferential speed of a first speed and a conveyance roller with the circumferential speed of a second speed, wherein the reverse roller is configured to be rotated with the circumferential speed of a third speed in the first drive step so that the reverse roller has a first separation performance for separating a sheet from other sheets, which are in an overlapped state, together with the feed roller with the circumferential speed of the first speed, wherein the feed roller conveys the specific sheet in a conveyance direction through the first drive step, wherein the image reading apparatus includes: the first motor; the second motor; the feed roller configured to rotate in a rotational direction by torque generated by the first motor so as to convey a sheet to in the conveyance direction; the reverse roller in peripheral contact with the feed roller, and configured to rotate in the rotational direction by torque received from the second motor via a torque limiter; the conveyance roller disposed downstream of the feed roller in the conveyance direction, and configured to rotate in the rotational direction by torque from the second motor so as to convey the sheet from the feed roller in the conveyance direction, the circumferential s

Assignees

• Brother Ind Ltd

Inventors

• Mukai Takaaki

Classifications

• B65H3/46 Primary

  Supplementary devices or measures to assist separation or prevent double feed (control means comprising detectors responsive to double feed B65H7/12) · CPC title

• H04N1/2032

  of two pictures corresponding to two sides of a single medium (refeeding a sheet for double-sided scanning H04N1/00572) · CPC title

• B65H2511/415

  of job · CPC title

• H04N2201/0094

  Multifunctional device, i.e. a device capable of all of reading, reproducing, copying, facsimile transception, file transception · CPC title

• H04N1/00602

  Feed rollers · CPC title