JPH0521270U - Fixing unit - Google Patents

Abstract

(57) [Abstract] [Purpose] With respect to the structure of a fixing unit of an electrophotographic recording apparatus, an object thereof is to ensure safety and improve adhesion when a cleaning member is replaced. [Structure] In a fixing unit that heat-fixes a sheet on which a toner image of an image carrier is transferred to a heat roller by pressing, a fixed frame that supports the heat roller and pressurizing that presses the sheet on the heat roller. A rotating frame for supporting the roller,
It is supported by the paper guide member of the rotating frame so as to be movable in a direction perpendicular to the axial length, and when the rotating frame is rotated to come into contact with the heat roller, it is pressed by the surface of the heat roller to move and incline the position. And a cleaning member which is in close contact with each other, guides the cleaning member to a predetermined position of the heat roller and rotates the cleaning member when the rotating frame is rotated to bring the cleaning member into contact with the heat roller.
It is configured to include a pressing member that presses against the blade.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to the structure of a fixing unit of an electrophotographic recording device. Recently, with the expansion of office automation (OA), plain paper can be used, and output devices with high printing quality have come to be used.

Therefore, a copying machine and a facsimile machine using the electrophotographic recording method have been realized. In these devices, cleaning of the fixing roller is also important in order to fix the toner image transferred on the paper with high quality.

[0003]

[Prior Art]

 As shown in the schematic view of FIG. 3, an electrophotographic recording apparatus to which the present invention is applied includes a photosensitive drum 1 which is an image carrier having a photosensitive layer on the surface thereof, the conductivity of which changes in response to light, and the photosensitive drum 1. Developing device 2 for adhering toner to the drum surface by a potential difference from the surface of the photosensitive drum 1, charging device 3 for uniformly charging the surface of the photosensitive drum 1, and changing the charging amount on the photosensitive drum 1 by scanning laser light. An optical system 4 for forming an electrostatic latent image, a transfer device 6 for transferring the toner image on the photosensitive drum 1 onto the paper 5, a halogen lamp for heating and fixing the toner image transferred onto the paper 5, and the like. The fixing unit 7 and the like are provided.

The fixing unit 7 includes a heat roller 8 and a pressure roller 9 for pressing the paper 5 against the heat roller 8 as shown in the side view of FIG. The pressure roller 9 is separable.

That is, the heat roller 8 is rotatably attached to the fixed frame 10 and the pressure roller 9 is rotatably attached to the rotating frame 11, and the rotating frame 11 is rotatable about the fulcrum 12 in the arrow A direction. ing.

If the toner remains on the heat roller 8, the toner adheres to and is fixed on the succeeding sheet, and deteriorates the recording quality. To prevent this, a cleaning member 13 such as a felt is pressed against the heat roller 8.

As shown in the side view of FIG. 5, the cleaning member 13 is supported by the supporting portion 10a of the fixed frame 10 via the holding member 13a. Therefore, when the cleaning member 13 is replaced, the gripping portion 13b protruding from the holding member 13a is pulled out.

Alternatively, as shown in the side view of FIG. 6, the cleaning member 13 has a holding member 13a for holding the cleaning member 13 supported by a paper guide member 14 fixed to the rotating frame 10. ing.

The sheet 5 on which the toner image on the photosensitive drum 1 has been transferred by the transfer device 6 in FIG. 3 is pressed by the pressure roller 9 and brought into pressure contact with the heat roller 8, and is heated by the heat roller 8 to generate the toner. The image is fixed on the sheet 5.

[0010]

[Problems to be solved by the device]

 As described above, the cleaning member opens the rotating frame and performs maintenance such as taking out and replacing the cleaning member. However, in the case of FIG. 5, there is a risk that the high temperature heat roller may be touched and burned.

Further, in the case of FIG. 6, there is no fear of burns, but when the rotating frame is rotated to press the cleaning member against the heat roller, the cleaning member is wrinkled as shown in the enlarged view of the main part of FIG. However, there is a problem that the adhesion is deteriorated due to the gap G between the heat roller and the cleaning effect, which is not sufficient.

An object of the present invention is to ensure safety and improve adhesion when a cleaning member is replaced.

[0013]

[Means for Solving the Problems]

 In the present invention, as shown in the side view of FIG. 1, a fixed frame 10 for supporting the heat roller 8 and a rotating frame 11 for supporting a pressure roller 9 for pressing the sheet 5 against the heat roller 8. Is supported by the paper guide member 14 of the rotating frame 11 so as to be free to move in the direction perpendicular to the axial length, and is pressed by the surface of the heat roller 8 when the rotating frame 11 is rotated and abuts against the heat roller 8. And a cleaning member 15 which is moved and tilted to be aligned and closely contacted.

When the rotating frame 11 is rotated to bring the cleaning member 15 into contact with the heat roller 8, the cleaning member 15 is guided to a predetermined position of the heat roller 8 and the cleaning member 15 is moved to the heat roller 8. 8 is provided with a pressing member 16 for pressing.

[0015]

[Action]

 The cleaning member is supported by the paper guide member so as to be movable in a direction perpendicular to the axial length. For this reason, when the rotating frame is rotated to bring the cleaning member into contact with the heat roller, the cleaning member is pressed by the surface of the heat roller and moves and tilts to automatically align and closely contact. Therefore, the cleaning member is not subjected to the sliding force due to the heat roller and wrinkles do not occur.

[0016]

【Example】

 In the present invention, as shown in the side view of FIG. 1, a fixed frame 10 for supporting the heat roller 8 and a rotating frame 11 for supporting a pressure roller 9 for pressing the sheet 5 against the heat roller 8. Is supported by the paper guide member 14 of the rotating frame 11 so as to be free to move in the direction perpendicular to the axial length, and is pressed by the surface of the heat roller 8 when the rotating frame 11 is rotated and abuts against the heat roller 8. And a cleaning member 15 which moves and tilts to be automatically aligned and closely contacted.

Therefore, the cleaning member 15 is not subjected to the force in the sliding direction due to the heat roller 8, and wrinkles do not occur. When the rotating frame 11 is rotated to bring the cleaning member 15 into contact with the heat roller 8, the cleaning member 15 is guided to a predetermined position on the heat roller 8 and the cleaning member 15 is pressed against the heat roller 8. The leaf spring-like pressing member 16 is provided.

As shown in the plan view of FIG. 2, the means for supporting the cleaning member 15 on the paper guide member 14 so as to be movable in the direction perpendicular to the axial length is two U's protruding from the holding member 15a for holding the cleaning member 15. Two L-shaped tongues 14a and 14b protruding from the paper guide member 14 are loosely fitted and held in the character-shaped protrusions 15b and 15c.

That is, the U-shaped projections 15b and 15c are fitted into the L-shaped tongues 14a and 14b with a sufficient gap in the height direction. Either one of the L-shaped tongue pieces 14a and 14b, for example, 14a, has a hook-shaped tip so that it is difficult to remove it once it is inserted into the U-shaped projection 15b.

Therefore, the cleaning member 15 is securely held by the paper guide member 14.

[0021]

[Effect of the device]

 According to the present invention, the cleaning member can be replaced safely by the operator, and the cleaning member can be properly pressed against the heat roller to improve the cleaning performance. Play.

[Brief description of drawings]

FIG. 1 is a side view of a fixing unit of the present invention,

FIG. 2 is a plan view showing a loose fitting structure of the cleaning member of the fixing unit of the present invention;

FIG. 3 is a schematic view of an electrophotographic recording device to which the present invention is applied,

FIG. 4 is a side view of a conventional fixing unit,

FIG. 5 is a side view showing a configuration when a conventional fixing unit is opened up and down,

FIG. 6 is a side view showing another configuration when the conventional fixing unit is opened vertically.

FIG. 7 is an enlarged view of a main part when wrinkles are formed on the cleaning member,

[Explanation of symbols]

 5 paper, 8 heat roller, 9 pressure roller, 10 fixed frame, 11 rotating frame, 12 fulcrum, 14 paper guide member, 14a, 14b L-shaped tongue piece, 15 cleaning member, 15a holding member, 15b, 15c U-shaped protrusion, 16 pressing member,

Claims (2)

[Scope of utility model registration request] 1. A fixing unit (10) for supporting the heat roller (8) in a fixing unit for thermally fixing the paper on which a toner image of an image carrier is transferred onto the heat roller (8). And a pressure roller that presses the paper against the heat roller (8).
A rotating frame (11) supporting the rotating frame (11) and a paper guide member (14) of the rotating frame (11) are supported so as to be movable in a direction perpendicular to the axial length, and rotate the rotating frame (11). And a cleaning member (15) which is pressed by the surface of the heat roller (8) to move and tilt to align and come into close contact with the heat roller (8) when moving and abutting against the heat roller (8). Fixing unit to do. 2. The cleaning member (15) is moved to the heat roller (8) when the rotating frame (11) of claim 1 is rotated to bring the cleaning member (15) into contact with the heat roller (8). ), And a fixing unit (16) for guiding the cleaning member (15) to the heat roller (8).