JPH09292804A - Exhausting device for image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to cool efficiently the interior of an apparatus by means of an exhausting device which cools the interior of the apparatus as well as removes ozone. SOLUTION: The device is provided with a first duct 13 which guides the air containing ozone existing in the vicinity of an image forming part A to the outside of an apparatus, a second duct 14 which guides the air existing in the vicinity of the fixing unit 9 to the outside, a fan 10 which transports the airs from the first and second ducts 13, 14 to the outside of the apparatus, an ozone filter which passes the air from the first duct 13 while removing ozone and a valve 12 which opens/closes the first duct 13. When it is not necessary to remove ozone, the valve 12 is closed to stop exhaustion on the image forming part A side so as to improve the efficiency of the exhaustion from the fixing unit 9 side.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air exhaust device for cooling the inside of an image forming apparatus and removing ozone, and more particularly to an air exhaust device for realizing the above-described internal cooling and ozone removal by one fan. .

[0002]

2. Description of the Related Art An image forming apparatus is provided with an exhaust device for removing ozone generated by a charging charger and a transfer separation charger provided in an image forming unit and exhausting heat generated by a fixing unit. There is something. In particular, in a small-sized and inexpensive type image forming apparatus, there is one in which one fan is used to exhaust air from the image forming unit and the fixing unit (see, for example, Japanese Patent Laid-Open No. 4-271633).

FIG. 3 shows an example of a conventional exhaust device having one fan. In the figure, a fan 10 and an ozone filter 11 are provided at positions communicating with the outside of the image forming apparatus. The heat generated from the fixing unit 9 of the fixing unit is sucked by the fan 10 and discharged outside the machine. At the same time, the ozone generated from the charging charger 2 and the transfer separation charger 7 in the image forming unit is removed by being sucked by the fan 10 and passing through the ozone filter 11. In the figure, 1 is a photosensitive drum, 3 is an exposure device, 4 is a developing unit, 5 is a paper feed roller, 6 is transfer paper, and 8 is a cleaning unit.

[0004]

However, in the above-mentioned conventional air exhaust device, since the cooling inside the machine and the removal of ozone are performed by one fan, even when the image forming section in which ozone is not operating does not operate. As a result, suction was performed from the vicinity of the image forming unit, and the efficiency of cooling the temperature inside the machine was wasted.

Therefore, according to the present invention, when it is not necessary to remove ozone, the exhaust air from the image forming unit is stopped, and the efficiency of the exhaust air from the fixing unit is increased, so that efficient image forming in the machine is possible. An object is to provide an air exhaust device for the device.

Further, in the conventional air exhaust system, the exhaust air from the fixing unit, which does not require ozone removal, is also used in the ozone filter 1.
However, there is a problem in that the life of the ozone filter is shortened because it passes 1.

Therefore, an object of the present invention is to provide an air exhaust device of an image forming apparatus capable of preventing early deterioration of the ozone filter by passing only the exhaust air that needs ozone removal through the ozone filter. There is.

[0008]

An exhaust device for an image forming apparatus according to the present invention is a first duct for guiding the air containing ozone in the vicinity of an image forming unit to the outside of the machine. A second duct for guiding the air in the vicinity of the fixing unit to the outside of the machine, one fan for sending the air from the first and second ducts to the outside of the machine, and a fan from the first duct. An ozone filter for passing air containing ozone to remove the ozone, and a valve for opening and closing the first duct are provided.

According to the second aspect of the present invention, a first duct for guiding the air containing ozone near the image forming section to the outside of the machine and a second duct for guiding the air near the fixing section to the outside of the machine. And one fan for sending air from the first and second ducts to the outside of the machine, third and fourth ducts provided outside the fan, and provided in the third duct. An ozone filter for removing the generated ozone and a valve for opening and closing the first, third, and fourth ducts are provided.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a schematic side sectional view in a first embodiment of an air exhaust system of the present invention. In the figure, an image forming unit A and a transfer unit B are installed in the image forming apparatus, and the air exhaust device according to the present invention is installed so that the image forming unit A, the transfer unit B and the outside of the machine communicate with each other. Has been done.

The air exhaust device has one fan 10 at a position communicating with the outside of the image forming apparatus and an ozone filter 11 further outside thereof. The duct on the inner side of the fan 10 is divided into two ducts 13 and 14 (hereinafter, referred to as an ozone duct 13 and a cooling duct 14) that communicate with the image forming unit A and the transfer unit B, respectively. The ozone duct 13 is for sending ozone generated from the charging charger 2 and the transfer separation charger 7 of the image forming unit A toward the ozone filter 11. This ozone duct 1
An on-off valve (or an on-off damper) 12 is provided in the middle of 3. The on-off valve 12 is closed when the charging charger 2 and the transfer separation charger 7 are not operating, that is, when ozone is not generated by these chargers. The open / close control of the open / close valve 12 can be performed based on a control signal from a control unit (not shown). During operation of the image forming unit A, the on-off valve 12 is opened, and the charging charger 2
The ozone generated by the transfer separation charger 7 is sucked by the fan 10 and sent to the ozone filter 11 to be filtered.

On the other hand, the cooling duct 14 is for discharging the heat generated by the fixing unit 9 of the transfer section B to the outside of the machine. The heat around the transfer portion B is sucked by the fan 10, passes through the cooling duct 14, passes through the ozone filter 11, and is discharged to the outside of the machine.

In the air exhaust system according to the present invention, when the charging charger 2 and the transfer separation charger 7 are not operating, the opening / closing valve 12 is closed and only the cooling duct 14 is communicated with the fan 10. As a result, all the suction force of the fan 10 is consumed for cooling the transfer portion B, and the capacity of the fan 10 can be utilized to the maximum.

In the above embodiment, the ozone duct 13 communicating with the image forming section A and the cooling duct 14 communicating with the transfer section B are formed by the inner wall 15 which divides one duct into two. It is also possible to install these two ducts separately.

FIG. 2 shows a schematic side sectional view of a second embodiment of the air exhaust system of the present invention. In this embodiment, the same parts as those in the previous embodiment are designated by the same reference numerals and the description thereof will be omitted. In the present embodiment, the exhaust device according to the present invention is configured by further dividing the duct portion on the outer side of the fan 10 into two by the inner wall 18 (hereinafter, ducts 16 and 17). An ozone filter 11 is attached to the downstream side of the one duct 16 to filter the discharged ozone.

On the upstream side of both ducts 16 and 17,
On-off valves 19 and 20 are provided respectively. On-off valve 1
9 and 20 are interlocked with each other, and are controlled so that when one opening / closing valve is open, the other opening / closing valve is closed. Further, these on-off valves 19 and 20 are used for the ozone duct 1
The on-off valve 12 in 3 is also interlocked, and when the on-off valve 12 is closed, the on-off valve 19 is closed and the on-off valve 20 is opened.

With this configuration, in the air exhaust device, the on-off valve 12 and the on-off valve 19 are closed and the cooling duct 14 and the duct 17 on the outside of the machine are fans when the charging charger and the transfer separation charger are not operating. It is connected to 10. As a result, all the suction force of the fan 10 is consumed for cooling the transfer portion B, and the capacity of the fan 10 can be utilized to the maximum. Further, in this case, the fan 10
The air discharged from the machine to the outside of the machine is controlled by the opening / closing valve 19 of the duct 16.
Is closed, the exhaust gas is discharged from the duct 17 without passing through the ozone filter 11. As a result, the exhaust air does not pass through the ozone filter 11 when it is not necessary to filter the ozone, so that the ozone filter does not work unnecessarily and its performance is prevented from prematurely deteriorating.

On the other hand, when the charging charger and the transfer separation charger are operating, the on-off valve 12 and the on-off valve 1
9 is opened and the on-off valve 20 is closed. As a result, the air containing the ozone from the image forming unit A passes from the cooling duct 14 to the duct 16 and is filtered by the ozone filter 11.

[0019]

As described above, in the exhaust device of the image forming apparatus according to the first aspect of the present invention, the duct leading from the inside of the machine to the fan is divided into two systems for cooling the transfer portion and removing ozone in the image forming portion. Since a valve is installed in the duct on the removal side, by closing the valve when ozone removal is not necessary,
Since the suction force of the fan can be used only for cooling the transfer portion, there is an effect that efficient cooling is performed.

In addition to the effect of claim 1, the air exhaust device of the image forming apparatus according to claim 2 is divided into two systems, a path leading from the fan to the outside of the machine to a path leading to the ozone filter and a path not passing to the ozone filter. Since a valve that can be opened and closed is installed in the valve, when exhausting air that does not require ozone removal, air is exhausted through a duct that does not have an ozone filter, so that the ozone filter does not work wastefully. The effect is that early deterioration of the performance can be prevented.

[Brief description of drawings]

FIG. 1 is a schematic side sectional view of a first embodiment of an air exhaust system of the present invention.

FIG. 2 is a schematic side sectional view of a second embodiment of an air exhaust system of the present invention.

FIG. 3 is a schematic side sectional view showing an example of a conventional air exhaust device.

[Explanation of symbols]

 A Image forming section B Transfer section 1 Photosensitive drum 2 Charging charger 3 Exposure 4 Developing unit 5 Paper feeding roller 6 Transfer paper 7 Transfer / separation charger 8 Cleaning unit 9 Fixing unit 10 Fan 11 Ozone filter 12 Open / close valve 13 Ozone duct 14 Cooling duct 15,18 Middle wall 16,17 Outside duct 19,20 Open / close valve

Claims (2)

[Claims] 1. A first duct for guiding the air containing ozone in the vicinity of the image forming unit to the outside of the machine, a second duct for guiding the air in the vicinity of the fixing unit to the outside of the machine, and the first and the first ducts. One fan for sending the air from the second duct to the outside of the machine, an ozone filter for passing the air containing ozone from the first duct to remove the ozone, and opening and closing the first duct An air exhaust device for an image forming apparatus, comprising: a valve. 2. A first duct for guiding the air containing ozone in the vicinity of the image forming unit to the outside of the machine, a second duct for guiding the air in the vicinity of the fixing unit to the outside of the machine, and the first and the first ducts. One fan for sending air from the second duct to the outside of the machine, and third and fourth ducts provided on the outside of the fan,
An air exhaust device for an image forming apparatus, comprising: an ozone filter installed in the third duct for removing ozone; and a valve for opening and closing the first, third, and fourth ducts.