Image reading apparatus

Patent metadata

Field	Value
Publication number	US-10630852-B2
Application number	US-201816143968-A
Country	US
Kind code	B2
Filing date	Sep 27, 2018
Priority date	Sep 29, 2017
Publication date	Apr 21, 2020
Grant date	Apr 21, 2020

Abstract

An image reading apparatus includes a roller that transports a document; a reading unit that reads an image of the document which is transported; a DC motor that drives the roller; and a control unit that controls the DC motor. The control unit is configured to stop driving of the DC motor in a case where a driving load value obtained when the DC motor is driven exceeds a threshold. A first threshold which is applied in a case of a first document and a second threshold which is applied in a case of a second document of which a basis weight is larger than a first basis weight are set, and the first threshold is less than the second threshold.

First claim

What is claimed is:

1. An image reading apparatus comprising:
a roller that rotates by being in contact with a document to transport the document along a transport path;
a reading unit that is disposed at a position in the transport path and reads an image from the document transported by the roller;
a DC motor that drives the roller; and
a control unit that controls the DC motor,
wherein the roller is capable of transporting a first document of which a basis weight is a first basis weight and a second document of which a basis weight is a second basis weight larger than the first basis weight, as respective transport targets,
wherein the control unit is configured to stop driving of the DC motor when a driving load value, obtained when the DC motor is driven, exceeds a first threshold which is applied in a case where the document is the first document or a second threshold which is applied in a case where the document is the second document are set, and the first threshold being less than the second threshold.

2. The image reading apparatus according to claim 1 ,
wherein a plurality of thresholds are set according to a difference in a transport speed of the document by the roller.

3. The image reading apparatus according to claim 1 ,
wherein the control unit stops the driving of the DC motor when a cumulative number of times in which the driving load value exceeds the first threshold reaches a set number of times in a case where the document is the first document, and stops the driving of the DC motor when a continuous time after the driving load value exceeds the second threshold reaches a set time in a case where the document is the second document.

4. The image reading apparatus according to claim 3 , further comprising:
a detection unit that outputs a detection signal at a stage completing reading of the image by the reading unit,
wherein the control unit resets the cumulative number of times or the continuous time stored at a time point when the detection unit outputs the detection signal.

5. The image reading apparatus according to claim 1 , further comprising, in an assumption that the roller and the DC motor are a first roller and a first DC motor:
a second roller that rotates by being in contact with the document at an upstream side of the transport path from the first roller to transport the document to a downstream side at which the first roller is positioned, and a second DC motor that drives the second roller,
wherein the control unit is configured to stop driving of the second DC motor in a case where a driving load value obtained when the second DC motor is driven exceeds a threshold.

6. The image reading apparatus according to claim 5 ,
wherein after the driving load value of the second DC motor increases after starting the transport of the document by the second roller, in a case where the driving load value of the second DC motor does not decrease even if an assumed time that the document reaches a position at which the first roller is disposed has elapsed, the control unit stops the driving of the second DC motor.

7. The image reading apparatus according to claim 5 ,
wherein after the driving load value of the second DC motor increases after starting the transport of the document by the second roller, in a case where the driving load value of the second DC motor does not decrease and further increases to exceed a threshold even if an assumed time that the document reaches a position at which the first roller is disposed has elapsed, the control unit stops the driving of the second DC motor.

Assignees

• Seiko Epson Corp

Inventors

• Arimori Kazuhiko
• Yoshikaie Kazuya
• Nomoto Kosuke

Classifications

• B65H2511/529

  number thereof, frequency of occurrence · CPC title

• B65H2513/512

  Starting; Stopping · CPC title

• B65H2515/32

  Torque e.g. braking torque · CPC title

• B65H2511/528

  Jam · CPC title

• B65H7/06

  responsive to presence of faulty articles or incorrect separation or feed (B65H7/14 takes precedence) · CPC title