Image reading apparatus and image forming apparatus

Patent metadata

Field	Value
Publication number	US-9554012-B2
Application number	US-201615171106-A
Country	US
Kind code	B2
Filing date	Jun 2, 2016
Priority date	Feb 10, 2014
Publication date	Jan 24, 2017
Grant date	Jan 24, 2017

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 guide shaft that guides reciprocation of the scanning unit;
a pull member that is arranged at a front side than the guide shaft, and 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; and
a pulley holder having a pulley axis that holds the following pulley rotatably,
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, and
the lock pawl is arranged at a side of a tension acting direction from the pull member to the following pulley among positions in a circumferential direction of the pulley axis and at a position except on a line extending from the axial center of the pulley axis to the tension acting direction.

2. The image reading apparatus according to claim 1 , further comprising a fixing member that fixes the pulley holder within the image reading apparatus, which being arranged at a side of the tension acting direction than the pulley axis.

3. The image reading apparatus according to claim 1 , wherein the lock pawl is arranged at a position in the side of the tension acting direction and to a line orthogonally intersecting a line passing the axial center of the pulley axis and extending toward the tension acting direction with a center line that is a line extending from the axial center of the pulley axis toward the tension acting direction.

4. The image reading apparatus according to claim 1 , further comprising a fixing member that fixes the pulley holder within the image reading apparatus, wherein
an axial center of the driving pulley, an axial center of the following pulley and a center of the fixing member are arranged on a straight line.

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

6. 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, and the pulley holder is fixed within the image reading apparatus in a movable manner in a direction of a line extending from an axial center of the pulley axis in the tension acting direction.

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

8. The image reading apparatus according to claim 1 , wherein the pulley axis further comprises a groove-like notched portion that is formed by notching a part in a circumferential direction thereof.

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