JPH0836347A - Electrostatic photographic device - Google Patents

Abstract

PURPOSE:To prevent an image forming unit side from being thermally affected from a fixing device by communicating a duct composed of a partition plate provided between the image forming unit and the fixing device and the sidewall of the fixing device therewith, so as to forcibly exhaust air. CONSTITUTION:The duct 15 constituted by using the partition plate provided between the fixing device 8 and the image forming unit 1 and a part of the housing 12 of the fixing device 8 in common is provided. The duct 15 shields heat radiated from the fixing device 8 to the image forming unit 1. When the electrostatic photographic device works, the air in the fixing device 8 is sucked and discharged through a large number of air holes 17 provided on the sidewall 12a of the housing 12 by a discharge fan 16 provided on one side of the duct 15 and the air in a machine body flows into the fixing device 8 from the entrance 13 and exist 14 of the fixing device 8. Thus, the radiant heat from the fixing device 8 is prevented from directly acting on the unit 1 and hot air in the fixing device 8 and the air in the machine body are discharged by the duct 15, to prevent the heat from being shut in the machine body.

Description

Detailed Description of the Invention

[0001]

The present invention relates to a printer, a copying machine,
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrostatic photography apparatus that records on paper by an electrostatic photography method such as a facsimile.

[0002]

2. Description of the Related Art In the above electrostatic photography apparatus, an original image from an optical system using laser light or the like is transferred onto a sheet as a toner image by an image forming unit, and the toner image on the sheet is fixed by a fixing device. It is designed to be heated and fixed. However, the components other than the fixing device, such as the image forming unit, are easily affected by the temperature and may be deteriorated by the heat of the fixing device or the toner blocking phenomenon may occur.

On the other hand, in the conventional electrostatographic device disclosed in Japanese Patent Laid-Open No. 5-40370, the heat of the fixing device does not affect the photoconductor of the image forming unit.
A partition plate is provided between the fixing device and the photoconductor of the image forming unit to prevent the heat of the fixing device from affecting the photoconductor and the like.

[0005]

However, in the conventional technique described above, it is necessary to open a sufficient space in the sheet passing portion between the partition plate and the image forming unit so as not to rub the image surface. There is a problem in that the heat of the fixing device becomes a hot air flow from this portion and flows into the image forming unit side, which adversely affects the photosensitive material of the photoconductor.

The present invention has been conceived in view of the above, and the hot air in the fixing device can be positively discharged from the electrostatic photography device to the outside, and the heat of the fixing device does not affect the image forming unit side. It is an object of the present invention to provide an electrostatic photography device of this type.

[0007]

In order to achieve the above object, an electrostatographic apparatus according to the present invention is provided with a toner image transferred onto a sheet by an image forming unit adjacent to the image forming unit. In an electrostatic photography apparatus in which a fixing device for heating and fixing is arranged, a partition plate for blocking heat from the fixing device is provided between the image forming unit and the fixing device, and at least the partition plate and the side wall of the fixing device are provided. Thus, a duct extending along substantially the entire length of the fixing device is provided so as to communicate with at least the fixing device, and an exhaust fan is provided at the end of this duct.

[0008]

[Operation] Radiant heat from the fixing device to the image forming unit is cut off even by the partition plate and the duct. Further, by driving the fan, hot air in the fixing device is discharged to the outside of the fuselage through this duct. Then, an airflow toward the fixing device is generated in the body.

[0009]

EXAMPLES Examples of the present invention will be described with reference to the drawings. In the figure, reference numeral 1 denotes an image forming unit, which comprises a photoconductor 2 and an optical system 3 including a laser light generator for irradiating the photoconductor 2 with a document image to form a latent image.
And a developing device 4 for developing the latent image on the photoconductor 2 into a toner image.
And a transfer device 7 for transferring the toner image on the photoconductor 2 onto the paper 6 supplied from the paper supply device 5.
A fixing device 8 and a paper discharge tray 9 for thermally fixing the toner image on the sheet onto which the toner image has been transferred are provided above the image forming unit 1 on the downstream side in the sheet traveling direction.

The fixing device 8 comprises a heat roll 10, a nip roll 11 and a housing 12 for accommodating them. One of the housings 12 has an inlet 13 for receiving the paper 6 from the image forming apparatus 1 and the other. An outlet 14 is provided through which the sheet 6 after fixing is discharged to the sheet discharge tray 9 side. The configuration of each part described above is substantially the same as that of a conventional general electrostatic photography apparatus.

A partition plate 15a is provided between the fixing device 8 and the image forming unit 1, and the partition plate 15a is provided.
And a part of the housing 12 of the fixing device 8 are provided in common, and the housing 15 of the fixing device 8 is provided by the duct 15 constituted by the partition plate 15a.
The radiant heat from the image forming unit 1 to the image forming unit 1 is cut off. An exhaust fan 16 is provided at one end of the duct 15. A large number of communication holes 17 are provided in the side wall 12a of the housing 12 shared by the ducts 15. The upper wall of the duct 15 shares a part of the paper discharge tray 9. Reference numeral 18 is a straightening plate.

In the above structure, the fan 16 is driven during operation of the electrostatographic apparatus. Therefore, the duct 15
The inside becomes negative pressure, and the air inside the fuselage is sucked from the open portion at one end of the duct 15 and the air inside the fixing device 8 is sucked and discharged from the ventilation hole 17 of the wall 12a of the housing 12.
Then, in the fixing device 8 at this time, the air inside the machine body flows in through the inlet 13 and the outlet 14.

Therefore, as shown by the arrow in FIG. 1, an air flow toward the opening of the duct 15 and the inlet 13 and the outlet 14 of the fixing device 8 is formed in the machine body, which causes new air to flow in the machine frame. Flows in, and heat is prevented from staying inside the aircraft.

On the other hand, the heat of the fixing device 8 is transferred to the image forming unit 1 side because the air inside the housing 12 is discharged through the duct 15 and the radiant heat thereof is cut off even by the partition plate 15a. It has no effect. In the above configuration, one end of the duct 15 may be closed so that the duct 15 communicates only with the fixing device 8.

[0014]

According to the present invention, since the duct 15 acts as a partition wall, it is possible to prevent the radiant heat from the fixing device 8 from directly acting on the image forming unit 1. Further, the hot air in the fixing device 8 is discharged through the duct 15, and the air inside the fuselage is also discharged through the duct 15, so that fresh air is constantly discharged into the fuselage, so that heat is not accumulated in the fuselage. .

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

FIG. 2 is a partially cutaway plan view showing an embodiment of the present invention.

[Explanation of symbols]

1 ... Image forming unit, 2 ... Photoreceptor, 3 ... Optical system, 4 ...
Developing device, 5 ... Paper feeding device, 6 ... Paper, 7 ... Transfer device, 8 ... Fixing device, 9 ... Paper ejection tray, 10 ... Heat roll, 11 ... Nip roll, 12 ... Housing, 12a ...
Housing wall, 13 ... Inlet, 14 ... Outlet, 15 ... Duct, 16 ... Fan, 17 ... Vent hole, 18 ... Straightening plate.

Claims (1)

[Claims] 1. An electrostatic photography apparatus comprising a fixing device adjacent to an image forming unit for heating and fixing a toner image transferred onto a sheet by the image forming unit,
A partition plate for blocking heat from the fixing device is provided between the image forming unit and the fixing device, and at least the partition plate and the side wall of the fixing device communicate with at least the duct extending along the substantially entire length of the fixing device to the fixing device. And an exhaust fan is provided at the end of this duct.