Image forming apparatus and fixing unit

Patent metadata

Field	Value
Publication number	US-2024045368-A1
Application number	US-202318487580-A
Country	US
Kind code	A1
Filing date	Oct 16, 2023
Priority date	Sep 15, 2021
Publication date	Feb 8, 2024
Grant date	—

Abstract

An image forming apparatus includes an image forming portion configured to form a toner image on a sheet, a fixing portion configured to heat and pressurize the sheet bearing the toner image to fix the toner image to the sheet, a shutter provided to be movable to an open position at which the shutter opens an opening that the sheet being conveyed toward the fixing portion is able to pass through, and a closed position at which the shutter closes the opening, an urging portion configured to urge the shutter toward the open position, and an abutment portion that the shutter urged toward the open position by the urging portion abuts to be positioned at the open position.

First claim

What is claimed is:

1 . An image forming apparatus comprising:
an image forming portion configured to form a toner image on a sheet; a fixing portion configured to heat and pressurize the sheet bearing the toner image to fix the toner image to the sheet; a shutter provided to be movable to an open position at which the shutter opens an opening that the sheet being conveyed toward the fixing portion is able to pass through, and a closed position at which the shutter closes the opening; an urging portion configured to urge the shutter toward the open position; and an abutment portion that the shutter urged toward the open position by the urging portion abuts to be positioned at the open position.

2 . The image forming apparatus according to claim 1 , wherein the shutter is provided to be pivotable between the open position and the closed position.

3 . The image forming apparatus according to claim 1 , further comprising:
a fixing frame in which the opening is provided; and a holder attached to the fixing frame, wherein the abutment portion is fixed to the fixing frame via the holder.

4 . The image forming apparatus according to claim 3 , wherein the shutter is supported by the fixing frame via the holder.

5 . The image forming apparatus according to claim 1 , further comprising:
a body frame; an opening/closing member openably and closably supported with respect to the body frame; and a link mechanism configured to move the shutter to the closed position against an urging force of the urging portion in accordance with an opening operation of the opening/closing member.

6 . The image forming apparatus according to claim 5 ,
wherein the link mechanism includes a first link member movable to a separation position where the first link member is separated from the shutter, and an abutting position where the first link member abuts the shutter, and wherein in a case where the first link member is positioned at the separation position, the shutter is positioned at the open position by being urged by the urging portion, and in a case where the first link member is positioned at the abutting position, the shutter is positioned at the closed position by being pressed by the first link member against an urging force of the urging portion.

7 . The image forming apparatus according to claim 6 , wherein the link mechanism includes
a link urging portion configured to urge the first link member toward the abutting position, and a second link member configured to move the first link member to the separation position against an urging force of the link urging portion in accordance with a closing operation of the opening/closing member.

8 . The image forming apparatus according to claim 7 , wherein the urging force of the link urging portion is larger than the urging force of the urging portion.

9 . The image forming apparatus according to claim 5 , wherein the opening/closing member constitutes at least part of an exterior of the image forming apparatus.

10 . The image forming apparatus according to claim 1 , further comprising:
a body frame; and a link mechanism, wherein the image forming portion includes a cartridge that is insertable into and removable from the body frame, and wherein the link mechanism is configured to move the shutter to the closed position against an urging force of the urging portion in accordance with an operation of pulling the cartridge out from the body frame.

11 . The image forming apparatus according to claim 10 ,
wherein the link mechanism includes a first link member movable to a separation position where the first link member is separated from the shutter, and an abutting position where the first link member abuts the shutter, and wherein in a case where the first link member is positioned at the separation position, the shutter is positioned at the open position by being urged by the urging portion, and in a case where the first link member is positioned at the abutting position, the shutter is positioned at the closed position by being pushed by the first link member against the urging force of the urging portion.

12 . The image forming apparatus according to claim 11 , wherein the link mechanism includes
a link urging portion configured to urge the first link member toward the abutting position, and a second link member configured to move the first link member to the separation position against an urging force of the link urging portion in accordance with an operation of inserting the cartridge into the body frame.

13 . The image forming apparatus according to claim 12 , wherein the urging force of the link urging portion is larger than the urging force of the urging portion.

14 . A fixing unit comprising:
a fixing portion configured to heat and pressurize a sheet bearing a toner image to fix the toner image to the sheet; a shutter provided to be movable to an open position at which the shutter opens an opening that the sheet being conveyed toward the fixing portion is able to pass through, and a closed position at which the shutter closes the opening; an urging portion configured to urge the shutter toward the open position; and an abutment portion that the shutter urged toward the open position by the urging portion abuts to be positioned at the open position.

15 . The fixing unit according to claim 14 , wherein the shutter is provided to be pivotable between the open position and the closed position.

16 . The fixing unit according to claim 14 , further comprising:
a fixing frame in which the opening is provided; and a holder attached to the fixing frame, wherein the abutment portion is fixed to the fixing frame via the holder.

17 . The fixing unit according to claim 16 , wherein the shutter is supported by the fixing frame via the holder.

Assignees

• Canon Kk

Inventors

• Toyota Akitoshi

Classifications

• G03G21/1647 Primary

  Mechanical connection means · CPC title

• G03G21/1685

  for the fixing unit · CPC title

• G03G15/2017 Primary

  Structural details of the fixing unit in general, e.g. cooling means, heat shielding means (G03G15/2053 takes precedence) · CPC title

• G03G21/1633

  using doors or covers (G03G21/1638 takes precedence) · CPC title