Image forming apparatus

• US 9,340,378 B2
• Filed: 03/15/2013
• Issued: 05/17/2016
• Est. Priority Date: 03/30/2012
• Status: Active Grant

• Current Assignee: Brother Kogyo Kabushiki Kaisha (Brother Industries Limited)
• Original Assignee: Brother Kogyo Kabushiki Kaisha (Brother Industries Limited)
• Inventors: Ueyama, Junki, Shimizu, Yoshikazu
• Primary Examiner(s): SUAREZ, ERNESTO A
• Application Number:
  US13/833,048
• Publication Number:
  US 20130256971A1
• Time in Patent Office: 1,159 Days
• Field of Search: 271/10.11, 271/113, 271/117, 271/118, 271/126, 271/127
• US Class Current: 1/1
• CPC Class Codes: B65H 2402/441 movable for facilitating access to area inside the housing, e.g. pivoting or sliding
• CPC Class Codes: B65H 2402/52 Bearings, e.g. magnetic or hydrostatic bearings
• CPC Class Codes: B65H 2404/17 Details of bearings
• CPC Class Codes: B65H 2601/324 Removability or inter-changeability of machine parts, e.g. for maintenance
• CPC Class Codes: B65H 3/0669 Driving devices therefor
• CPC Class Codes: B65H 5/06 by rollers or balls, e.g. between rollers transport by suction rollers B65H5/226
• CPC Class Codes: G03G 15/652 Feeding a copy material originating from a continuous web roll
• CPC Class Codes: G03G 21/1633 using doors or covers G03G21/1638 takes precedence
• CPC Class Codes: G03G 21/1695 for paper transport

Abstract

An image forming apparatus includes a main body, a recording sheet receiving portion configured to receive a recording sheet, an image forming portion configured to form an image on the recording sheet, a particular feed roller configured to feed the recording sheet toward the image forming portion, and a holding frame configured to rotatably support the particular feed roller such that the particular feed roller is exposed toward the recording sheet receiving portion. The holding frame has a roller receiving portion configured to receive the particular feed roller therein and a replacement opening for exposing the particular feed roller toward an opposite side of the holding frame relative to the recording sheet receiving portion. The particular feed roller is configured to be attached to and removed from the holding frame via the replacement opening on the opposite side of the holding frame relative to the recording sheet receiving portion.

Claims

1. An image forming apparatus comprising:

a main body including a top cover configured to open and close an upper opening;

a recording sheet receiving portion configured to receive a recording sheet and disposed in a lower portion of the main body;

an image forming portion disposed in the main body and configured to form an image on the recording sheet, the image forming portion including a process cartridge configured to be attached to and removed from the main body through the upper opening opened by the top cover;

a feed roller unit including a pickup roller, a separation roller, and a connecting member, the connecting member holding the pickup roller and the separation roller such that the pickup roller is disposed upstream of the separation roller in a sheet feeding direction, the pickup roller being configured to rotate in contact with the recording sheet received on the recording sheet receiving portion, the separation roller being configured to rotate in contact with the recording sheet fed by the pickup roller to feed the recording sheet toward the image forming portion, the connecting member having an upper wall, the upper wall completely covering an upper portion of the pickup roller;

a holding frame disposed between the recording sheet receiving portion and the image forming portion and configured to support the feed roller unit such that the pickup roller and the separation roller are exposed toward the recording sheet receiving portion;

a drive gear disposed in one end portion of the holding frame in a width direction of the recording sheet and configured to transmit a rotational driving force to the separation roller;

a roller shaft connecting the drive gear and the separation roller; and

a bearing configured to rotatably support an opposite side of the separation roller relative to the roller shaft,

wherein the holding frame has a roller receiving portion configured to receive the feed roller unit therein,

wherein the feed roller unit is configured to be attached to and removed from the holding frame via the roller receiving portion on an opposite side of the holding frame relative to the recording sheet receiving portion,

wherein the upper wall of the feed roller unit, which completely covers the upper portion of the pickup roller, is exposed through the upper opening opened by the top cover when the process cartridge is removed from the main body, and

wherein the upper wall of the feed roller unit, which completely covers the upper portion of the pickup roller, is covered by the process cartridge when the process cartridge is attached to the main body,

wherein the roller shaft protrudes by a specified distance inside the roller receiving portion, and

wherein the roller receiving portion is sized to allow the feed roller unit to move the specified distance or more in the width direction inside the roller receiving portion, and

wherein the bearing is configured to engage the holding frame such that the bearing moves with respect to the holding frame and movement of the bearing in the width direction is limited.

2. The image forming apparatus according to claim 1, wherein the process cartridge includes a photosensitive member.

3. The image forming apparatus according to claim 1,

wherein the image forming portion includes:

another process cartridge including another photosensitive member; and

a belt disposed facing the process cartridge and the other process cartridge.

4. The image forming apparatus according to claim 1, wherein the recording sheet receiving portion is configured to move toward and away from the pickup roller, which is disposed upstream of the separation roller in the sheet feeding direction.

5. The image forming apparatus according to claim 1, wherein the recording sheet fed from the recording sheet receiving portion is turned in a shape of a letter U in the main body and ejected outside the main body.

6. The image forming apparatus according to claim 1,

wherein the pickup roller, which is disposed upstream of the separation roller in the sheet feeding direction, is configured to pivot about the separation roller, and

wherein the recording sheet receiving portion is configured to move toward and away from the pickup roller.

7. The image forming apparatus according to claim 1, wherein the feed roller unit further includes an idle gear engaging both of a gear of the pickup roller and a gear of the separation roller.

8. The image forming apparatus according to claim 1, wherein the roller receiving portion of the holding frame has a hole through which the roller shaft connects the drive gear and the separation roller.