Image reading apparatus and image forming apparatus

Patent metadata

Field	Value
Publication number	US-9894234-B2
Application number	US-201615372473-A
Country	US
Kind code	B2
Filing date	Dec 8, 2016
Priority date	Feb 10, 2014
Publication date	Feb 13, 2018
Grant date	Feb 13, 2018

Abstract

A driving device is used in an image reading apparatus, and reciprocates a scanning unit for reading an image on an original. The driving device comprises a pull member, a driving pulley which transmits driving force to the pull member, a following pulley which applies tension to the pull member and a pulley holder having a pulley axis which holds the following pulley rotatably. Then, the pulley axis has a lock pawl capable of locking an upper end portion of the following pulley and canceling engagement with the following pulley by being tilted toward a side of an axial center by elastic deformation. Furthermore, the lock pawl is arranged at a side of a tension acting direction from the pull member to the following pulley except the farthest position from the driving pulley among positions in a circumferential direction of the pulley axis. It is possible to attach and detach the following pulley easily at a time of maintenance or the like.

First claim

What is claimed is:

1. An image reading apparatus that comprises an original platen and a scanning unit for reading an image on an original put on the original platen, comprising:
a pull member that pulls the scanning unit;
a driving pulley that transmits driving force to the pull member;
a following pulley that the pull member is wound thereon while keeping a state where tension is applied to the pull member;
a pulley holder having a pulley axis that holds the following pulley rotatably and provided in a movable manner; and
a guide portion that guides a movement of the pulley holder, wherein
the pulley holder is formed with one or more projections on a side surface thereof, and the projection is brought into contact with the guide portion in a slidable manner.

2. The image reading apparatus according to claim 1 , wherein the pulley axis has a lock pawl that can lock the following pulley and cancel engagement with the following pulley by being tilted toward a side of an axial center of the pulley axis by elastic deformation.

3. The image reading apparatus according to claim 1 , wherein the projections are formed with two on each of both side surfaces of the pulley holder.

4. The image reading apparatus according to claim 1 , wherein each of the projections is formed in a semicircular shape in a plan view.

5. The image reading apparatus according to claim 1 , wherein the guide portion is formed on a bottom surface of a housing of the image reading apparatus.

6. The image reading apparatus according to claim 1 , wherein the pulley axis has two lock pawls.

7. The image reading apparatus according to claim 1 , wherein the pulley holder further comprises another projection that is projected upwardly from an end of the driving pulley side.

8. The image reading apparatus according to claim 1 , further comprising a fixing member that fixes the pulley holder within the image reading apparatus, wherein
the pulley holder is formed with a long hole into which the fixing member is inserted.

9. An image forming apparatus comprising the image reading apparatus according to claim 1 .

Assignees

• Sharp Kk

Inventors

• Imoto Masahiro
• Suto Yasuhiro
• Fukutome Shohichi
• Nakanishi Kenji
• Iguchi Kazuhiro

Classifications

• Y10T74/18848

  with pulley · CPC title

• G03G21/1666

  for the exposure unit · CPC title

• G03G15/60

  Apparatus which relate to the handling of originals (for photographic purposes in general G03B) · CPC title

• G03G15/04

  for exposing, i.e. imagewise exposure by optically projecting the original image on a photoconductive recording material · CPC title

• F16H19/0672

  characterised by means for tensioning the flexible member · CPC title