JP3067442B2 - Image forming device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus such as a facsimile apparatus provided with a heat fixing device for fixing an image formed on recording paper by heat.

[0002]

2. Description of the Related Art In general, in a facsimile apparatus of this type, an electrostatic latent image is formed on a photosensitive drum, toner adheres to the electrostatic latent image, and is deposited on recording paper based on charging of the peripheral surface of the photosensitive drum. Is performed. Then, the toner image transferred on the recording paper is
The heat is fixed by a heat fixing device.

The heat fixing device generates a high temperature in order to heat-fix toner on recording paper. For this reason, a cover that covers the heat fixing unit is fixed to a frame in the apparatus case so that the heat fixing unit is not burned by touching the heat fixing unit at the time of toner replenishment, drum replacement, and the like when the toner is supplied. On the discharge side of the heat fixing unit, a recording paper guide for guiding the recording paper on which heat fixing has been performed to the discharge side is fixedly mounted on the frame.

[0004]

However, in the facsimile apparatus described above, the number of components is increased because the heat fixing device and the recording paper guide are separately formed, and the facsimile apparatus has to be individually mounted on the frame. Since they need to be performed, the number of assembling work steps increases. As a result, there is a problem that the cost increases.

[0005] The present invention has been made to solve the above problems, its object is to reduce the number of parts of the entire device, it is possible to reduce the cost, the cover
An object of the present invention is to provide an image forming apparatus which does not cause a burn even when touched .

[0006]

In order to achieve the above object, according to the present invention, a frame is disposed above a heat fixing unit for heat fixing an image formed on a recording sheet.
A cover that covers the frame and a cover that covers the heat-fixing device, and the cover integrally forms a recording paper guide that guides the recording paper on which the image is thermally fixed by the heat-fixing device to a discharge side. Is the gist.

[0007]

According to the above construction, since the cover and the recording paper guide are integrally formed, the number of parts of the entire apparatus is reduced. Moreover, the hot air rising from the heat fixing device
Is blocked by the Therefore, this hot air
The temperature of the heating unit rises to a certain degree,
Then do not raise the temperature.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. As shown in FIG. 1, the apparatus case 1 is formed in a substantially box shape having an open upper surface, and an opening / closing lid 2 is supported by a support shaft 3 at the upper surface opening so as to be openable and closable. The photosensitive drum 4 is rotatably supported in the apparatus case 1, and a photoconductive film 5 is formed on an outer peripheral surface thereof. The charger 6 is arranged to face the upper periphery of the photosensitive drum 4 and uniformly charges the photoconductive film 5 to a predetermined potential. The exposure device 7 forms an electrostatic latent image of a predetermined potential on the photosensitive drum 4 by irradiating light.

The developing device 9 includes a toner case 10 for containing the toner T, a toner cartridge 11 removably mounted on the toner case 10, and a photosensitive drum 4.
And a developing roller 12 disposed at an opening at the lower end in the toner case 10 so as to be close to and opposed to the developing roller 12. Then, a predetermined potential is applied to the toner T by the developing roller 12, and based on a difference between the potential and the potential of the electrostatic latent image, the toner T is attached to the electrostatic latent image, and the electrostatic latent image is visualized. Imaged.

The paper cassette 13 stores a large number of recording papers P in a stacked state. When the paper feed roller 15 is rotated, the recording paper P is removed from the paper cassette 13.
Are fed out one by one, and the recording paper P is fed into the recording paper guide 16.
Then, the photosensitive drum 4 is transferred to a lower portion of the photosensitive drum 4 via a pair of feed rollers 17.

The transfer unit 18 and the guide roller 19 are arranged to face the outer periphery of the lower portion of the photosensitive drum 4 with the recording paper transfer path interposed therebetween. Then, the recording paper P is brought into close contact with the photosensitive drum 4 by the guide roller 19, and a predetermined potential is applied to the contact portion by the transfer device 18, and based on the difference between the potential and the potential of the toner image, The toner image is transferred onto the recording paper P.

The charge removing lamp 20 exposes the outer peripheral surface of the photosensitive drum 4 after the transfer to remove the charge. The cleaning brush 21 removes paper dust and the like adhering on the photosensitive drum 4 after the transfer. The memory removing brush 22 made of a conductive brush disturbs the toner T remaining on the photosensitive drum 4 after the transfer and uniformly distributes the toner T on the photosensitive drum 4.

A heat fixing unit 23 is disposed downstream of the photosensitive drum 4. As shown in FIGS. 1 and 2, the heat fixing device 23 includes a heating roller 24 and the heating roller 24.
And a pressure roller 25 that comes into contact with a required pressure across the recording paper transfer path. Then, the recording paper P passes through the recording paper guide 26 and the heating roller 24 and the pressure roller 25.
And the toner image on the recording paper P is heated and fixed at a predetermined temperature.

A frame 27 is arranged above the heat fixing unit 23. On the upper surface of the frame 27, a heat fixing unit cover 28 made of synthetic resin that covers the heat fixing unit 23 is attached and fixed so that an operator does not touch the heat fixing unit 23 when the toner is supplied or the like to cause burns.

As shown in FIGS. 1 to 4, a plurality of ribs 29 are formed on the upper surface of the heat fixing unit cover 28. The rib 29 reinforces the heat fixing unit cover 28 and promotes the heat radiation action of the cover 28. Further, a through hole 28a is formed in the center of the heat fixing unit cover 28 so as to extend in the width direction and open. This through hole 28a
, A cleaner 31 having a felt 30 attached to the tip thereof is detachably engaged. The felt 30 comes into contact with the outer peripheral surface of the heating roller 24 and is
Cleaning the toner and the like adhering to. The cleaner 31 is supported from below by contact between the felt 30 and the heating roller 24, and is pressed from above by a leaf spring (not shown).

The front side of the heat fixing unit cover 28 (FIG. 1)
, A pair of plate-shaped recording paper guides 32 are formed integrally at a plurality of locations at equal intervals. The recording paper guide 32 includes a heating roller 24 and a pressure roller 25.
The recording paper P sent from between is guided to the tray 34 side together with the recording paper guide 33 facing the recording paper P. Further, as shown in FIGS. 1 and 2, on one side of the recording paper guide 32, a plurality of separation claws 35 are supported so as to be rotatable about a rotation shaft 36. The separation claw 35 is constantly urged in a counterclockwise direction (in FIG. 1) by a spring 37, and its tip is always in contact with the outer peripheral surface of the heating roller 24. The separation claw 35 is configured such that the recording paper P is
The recording paper P is separated from the heating roller 24 when the recording paper P passes between them.

As described above, in the facsimile apparatus of the present embodiment, the heat fixing unit cover 28 for preventing contact with the heat fixing unit 23 is provided above the heat fixing unit 23. Then, the hot air rising from the heat fixing device 23 is blocked by the frame 27. And the frame 27
Rises to some extent, but does not rise to the temperature of the outer peripheral surface of the heat fixing device 23. Therefore, the temperature of the heat fixing unit cover 28 does not rise so much, and even if the cover 28 is touched, there is no possibility that a burn is caused.

Further, in the present embodiment, the recording paper guide 32 for guiding the recording paper P on which heat has been fixed to the discharge side is formed integrally with the heat fixing unit cover 28. As a result, the number of parts of the entire apparatus is reduced as compared with the case where the heat fixing unit cover 28 and the recording paper guide 32 are separate parts, so that the number of assembling steps is reduced and cost is significantly reduced. Can be.

The present invention is not limited to the above-described embodiment. For example, the heat fixing unit cover 28 and the cleaner 3
For example, it can be changed within a range that does not deviate from the gist of the invention, for example, by integrally forming 1 and the like.

[0020]

As described in detail above, according to the present invention,
It is possible to reduce the entire apparatus parts, both when it is possible to greatly reduce the cost, the cover
To touch an excellent effect called a never as burns.

[Brief description of the drawings]

FIG. 1 is a partial sectional view of a facsimile apparatus according to an embodiment of the present invention.

FIG. 2 is a partially enlarged cross-sectional view of the vicinity of a heat fixing device.

FIG. 3 is a perspective view of a heat fixing unit cover.

FIG. 4 is a plan view of a heat fixing unit cover.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Device case, 23 ... Heat fixing device, 27 ... Frame,
28: heat fixing unit cover as a cover, 32: recording paper guide, P: recording paper.

Claims (1)

(57) [Claims] 1. A frame is disposed above a heat fixing device for thermally fixing an image formed on recording paper.
An image forming apparatus which covers the frame and covers the heat fixing unit, and the cover is integrally formed with a recording paper guide for guiding the recording paper on which the image has been thermally fixed by the heat fixing unit to a discharge side. apparatus.