JPH08220952A - Image forming device - Google Patents

Abstract

PURPOSE: To provide an image forming device in which operation for removing toner and ozone and operation for air-cooling a fixing device are separately performed without interference and efficiently performed without wasterful power consumption. CONSTITUTION: A 1st exhaust part equipped with a dust collecting filter 22, an ozone filter 21, a fan 23 and a fan for sucking outside air 27, and provided in an air current path including a developing device 10 is actuated so as to perform the collection of scattered toner from the developing device 10 and the adsorption and the exhaust of ozone generated by an electrifier 24 under the control of a control means. Then, a 2nd exhaust part equipped with a fan 26, and provided separately from the 1st exhaust part in an air current path including the fixing device 15 is actuated so as to perform the operation for air-cooling the fixing device 15 without mutual interference in the operation of the 1st exhaust part. Under such exhaust operation, a high-quality image is formed by exposing an original image to an image carrier, developing an obtained electrostatic latent image, transferring and thermally fixing the obtained toner image on transfer paper.

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 copying machine.

[0002]

2. Description of the Related Art FIG. 6 is an explanatory view showing the overall structure of a conventional image forming apparatus. An image forming section 41 for forming an image is provided in an intermediate portion of a housing 40, and below the image forming section 41. A paper feed unit 42 for feeding transfer paper to the image forming unit 41
Above the image forming unit 41, there is provided a scanner unit 1 that optically captures a document image and exposes the document image to the image forming unit 41.

The scanner unit 1 is provided with a document illumination lamp 2 and a mirror group 3 which are driven by a motor (not shown) to scan and read a document image, and the light emitted from the document illumination lamp 2 is reflected from the document image. The light is taken by the mirror group 3 into the lens 4 arranged in the rear stage of the mirror group 3,
An image is formed on the color image sensor 5 arranged in the subsequent stage.

In the scanner section 1, R (Red) G (Green) of the original image formed on the color image sensor 5 is formed.
n) A color conversion process is performed by an image processing unit (not shown) on the basis of the B (Blue) color-separated image signal, and BK (Bl)
ack), C (Cyan), M (Magenta), Y
(Yellow) color image data is obtained.

The color image data thus obtained is converted into an optical signal of a laser, the optical signal is made incident on the polygon mirror 6, and the f / θ lens 7 disposed at the subsequent stage of the polygon mirror 6, The light is incident on the photoconductor drum 9 provided in the image forming section 41 through the reflection mirror 8 provided at the subsequent stage of the f / θ lens 7 and corresponds to the original image on the photoconductor drum 9. The optical signal is exposed to form an electrostatic latent image of the original image on the photosensitive drum 9.

In the image forming section 41, the photosensitive drum 9 is rotated with respect to the photosensitive drum 9 rotating counterclockwise.
The developing device 10 is disposed so as to closely face the peripheral surface of the developing device 10, and the intermediate transfer belt 11 that is transported in contact with the photoconductor drum 9 is disposed downstream of the developing device 10 in the counterclockwise direction. ing. Here, the developing / transferring operation of developing the electrostatic latent image on the rotating drum 9 into a toner image by the toner supplied from the developing device 10 and further transferring it to the intermediate transfer belt 11 is performed by BK, C, M, and By carrying out four times for Y, a four-color superposed toner image is formed on the intermediate belt 11.

In the image forming section 41, a paper transfer roller 13 is disposed in contact with the intermediate transfer belt 11, and transfer paper conveyed from the paper feeding section 42 is placed between the intermediate transfer belt 11 and the paper transfer roller 13. A registration roller 12 for sending in is provided, and the toner image on the intermediate transfer belt 11 is transferred to the transfer paper sent by the registration roller 12 by the paper transfer roller 13.

A paper transport unit 14 for transporting the transfer paper is provided at the rear stage of the intermediate transfer belt 11, and the transfer paper on which the toner image has been transferred is transported by the paper transport unit 14 and at the rear stage of the paper transport unit 14. The toner image is fused and heat-fixed on the transfer paper by the fixing device 15, and the original image is formed on the transfer paper.

FIG. 4 is an explanatory view showing the structure of the exhaust section of the conventional image forming apparatus, and FIG. 5 is a perspective explanatory view showing the structure of the flow path of the exhaust section of the conventional image forming apparatus.

By the way, the image forming apparatus includes a developing device 10
The toner that scatters during the developing operation is collected and removed, and the fixing device 1
An air exhaust unit is provided for performing air cooling with respect to heat radiation from 5, and for absorbing and decomposing ozone generated when the photosensitive drum 9 is charged. In this exhaust section, as shown in FIG.
As shown in FIG. 3, an airflow inlet 10b for taking in an airflow is formed at one end of the frame 10A of the developing device 10, and an airflow outlet 10c for discharging the airflow is formed at the other end of the frame 10A. The duct 20 is provided between the 10c and the exterior exhaust port 30 provided in the housing 40.

In the duct 20, the exterior exhaust port 3
The exhaust fan 23 is provided facing 0, and the exhaust fan 23
Between the air flow outlet 10c and the air flow outlet 10c, the dust collecting filter 22 is provided on the air flow outlet 10c side and the ozone filter 21 is provided on the exhaust fan 23 side.
Are arranged so as to be in contact with each other and be detachable from the duct 20. Further, an exhaust port 20a is formed in the lower plate 20d of the duct 20, and the housing 4 is opposed to the exhaust port 20a.
A fixing device 15 is provided in the area 0.

As shown in FIG. 5, two exhaust fans 23 are mounted on the left and right sides of the duct 20 so as to face the exterior exhaust port 30. When the exhaust fans 23 operate, the developing operation of the developing device 10 is started. Scattered toner and charging charger 2
The air flow containing ozone generated during the charging operation of FIG.
And, as indicated by an arrow A in FIG. 5, the air flows out from the airflow outlet 10c, passes through the dust collecting filter 22 and the ozone filter 21, and passes through the exhaust fan 23 and from the exterior exhaust port 30,
It is released to the outside of the housing 40.

In this way, the toner in the air stream is removed by the dust collecting filter 22, and the ozone in the air stream is
It is adsorbed and decomposed by the ozone filter 21. Then, a new airflow flows into the developing device 10 from the airflow inlet 10b.

On the other hand, the air heated by the heat radiation during the fixing operation of the fixing device 15 passes through the exhaust port 20a and the exhaust fan 23 as shown by an arrow B in FIGS.
The air is discharged from the exterior exhaust port 30 to the outside of the housing 40, and the fixing device 15 is air-cooled.

[0016]

In the above-mentioned conventional image forming apparatus, the toner and ozone suction airflow and the fixing device 15 are used.
And the airflow of the air cooling are combined and discharged through the exhaust fan 23 to the outside of the housing 40, and the toner and ozone removing operation and the air cooling operation of the fixing device 15 are simultaneously performed. For this reason, even when the apparatus is in the standby state, it is necessary to drive the exhaust fan 23 for air-cooling the fixing device that stands by at the standby temperature, which causes noise and wasteful power consumption. . Further, the toner and ozone removing operation and the fixing device 15
The air-cooling operations of the above may interfere with each other, and these operations may be affected in the direction of deterioration.

The present invention has been made in view of the current state of the exhaust operation in the housing for dust collection and air cooling of the image forming apparatus as described above, and its purpose is to remove toner and ozone, and An object of the present invention is to provide an image forming apparatus in which the air-cooling operation of a fixing device is separated from each other without interfering with each other and can be performed efficiently and without wasting power.

[0018]

In order to achieve the above-mentioned object, the invention according to claim 1 exposes a document image on an image carrier and develops the obtained electrostatic latent image by a developing device to obtain the image. An image forming apparatus for transferring a formed toner image onto a transfer sheet and performing heat fixing to form an image of an original image. The image forming apparatus is provided in a flow path of an air flow including the developing device, and has a replaceable filter and an exhaust fan A first exhaust part that includes a fan and collects the scattered toner from the developing device to exhaust the air; and an air flow path that includes the fixing device and is provided separately from the first exhaust part. And a second exhaust unit that includes a cooling fan and that exhausts the fixing unit for cooling, the first exhaust unit, and the second exhaust unit.
And a control means for controlling the operation with the exhaust part.

Similarly, in order to achieve the above object, in the invention according to claim 2, in the invention according to claim 1, the first exhaust part and the second exhaust part are provided in a common duct. It is characterized by being formed separately.

Similarly, in order to achieve the above object, the invention according to claim 3 is the image forming apparatus according to claim 1, wherein an outside air suction fan is provided at the inlet of the first exhaust unit. It is characterized by being present.

[0021] Similarly, in order to achieve the above-mentioned object, in the invention according to claim 4, in the invention according to claim 1, the control means stops the operation of the first exhaust portion when the operation is on standby. It is characterized by.

[0022]

According to the first or second aspect of the present invention, the first exhaust unit provided with the filter and the exhaust fan and provided in the flow path of the air flow including the developing device is operated by the control of the control means. Then, dust is scattered from the developing device and ozone is adsorbed while ozone is adsorbed, and the second exhaust gas is provided separately from the first exhaust part in the air flow passage including the fixing device. The section is activated to provide cooling exhaust to the fuser. Then, under such an exhaust operation, the original image is exposed on the image carrier, the obtained electrostatic latent image is developed by the developing device, the obtained toner image is transferred to the transfer paper, and the heat fixing is performed. Then, an image of the original image is formed.

According to the third aspect of the present invention, in addition to the operation of the first aspect of the invention, the air flow for dust collection or ozone absorption is provided by the outside air suction fan provided at the inlet of the first exhaust section. Sufficiently obtained from outside the device.

In the invention of claim 4, in the operation of the invention of claim 1, the control means stops the operation of the first exhaust portion during the standby operation.

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described below with reference to FIGS.
Will be described with reference to. FIG. 1 is an explanatory view showing the structure of the exhaust part of the present embodiment, FIG. 2 is a perspective explanatory view showing the structure of the flow path of the exhaust part of the present embodiment, and FIG. 3 is the structure of the flow path of the exhaust part of the present embodiment. FIG.

In the exhaust portion of this embodiment, as shown in FIGS. 2 and 3, the exhaust hole 2 is formed in the center of the lower plate 20d of the duct 20.
0b is formed and the duct 2 corresponding to the exhaust hole 20b is formed.
A fan 26 used for air-cooling the fixing device 15 is attached to the center position of the front plate 20f of 0, and two fans 23a are sandwiched with the fan 26 interposed therebetween as in the case of the conventional image forming apparatus. The fan 23a attached to the front plate 20f is used for sucking the toner scattered from the developing device 10 and the ozone generated by the charging charger 24.

Further, in this embodiment, the frame 1 of the developing device 10 is used.
The airflow inlet 10b of 0A is connected to the outside of the housing 40 and the airflow pipe 45.
An outside air suction fan 27 for sucking outside air is attached near the airflow inlet 10b.

In the image forming apparatus according to this embodiment, an operation for sucking and removing scattered toner and ozone in the exhaust portion,
A control unit (not shown) for independently controlling the air-cooling operation of the fixing device 15 is provided, and this control unit stops the fan 23a and the outside air suction fan 27 when the image forming operation of the image forming apparatus is on standby. Then, it has a function of stopping the suction and removal operation of the scattered toner and ozone in the exhaust portion.

The structure of the other parts of the present embodiment is the same as that of the conventional image forming apparatus already described with reference to FIGS. 4 to 6, and therefore will not be described again.

In the present embodiment, when the image forming operation is started, the fan 23a and the outside air suction fan 27 are driven by the command of the control means, and the toner scattered during the operation of the developing device 10, As shown by the arrow A in FIG. 1, the air containing ozone generated when the charging charger 24 operates is
It becomes an air flow and flows into the duct 20 from the air flow outlet 10c. The airflow that has flowed into the duct 20 is a dust collection filter 22.
And the ozone filter 21 and passes through the dust collecting filter 22.
By this, the toner in the air stream is removed, and the ozone in the air stream is adsorbed and decomposed by the ozone filter 21.

The airflow from which the toner and ozone have been removed in this way passes through the exhaust fan 23 and the exterior exhaust port 30.
Is discharged to the outside of the housing 40, and outside air is sucked into the periphery of the developing device 10 from the airflow inlet 10b by the outside air suction fan 27.

Then, in response to a command from the control means, the fan 23a and the outside air suction fan 2 are operated during the image forming operation.
7, the ozone generated by the charger 24 and the toner scattered from the developing device 10 are removed by the ozone filter 21 and the dust collecting filter 22. The ozone filter 21 and the dust collecting filter 22 are removed from the duct 20 and replaced when they are used for a predetermined time set in advance.

When the image forming operation is started, the air whose temperature has risen due to heat radiation from the fixing device 15 driven by the fan 26 in accordance with a command from the control means is indicated by an arrow B in FIGS. 1 to 3. As shown in the drawing, the air flows into the exhaust hole 20b, is discharged from the exterior exhaust port 30 through the fan 26 to the outside of the housing 40, and the fixing device 15 is air-cooled. This air cooling operation is continued even when the apparatus is in the standby state, and the fixing device 1
5 is in a standby state at a predetermined standby temperature in preparation for a quick response to the fixing operation. In this case, the fan 23a is stopped,
Since only the fan 26 is driven, the noise is greatly reduced.

When the image forming operation is completed, the fan 26 is stopped and the air-cooling operation of the fixing device 15 is stopped after a predetermined time has elapsed from the end of the image forming operation according to a command from the control device.

As described above, according to this embodiment, the air flow passage for collecting dust of toner and the adsorption of ozone and the air flow passage for air cooling of the fixing device 15 are separately formed in the housing 40. Therefore, the dust collection of toner and the adsorption operation of ozone and the fixing device 15
The air-cooling operation does not interfere with each other and adversely affect each other.

Generally, when the temperature of the developing device 10 rises,
The charging property of the toner deteriorates, and in the conventional image forming apparatus,
When the dust collection filter 22 collects dust and the air flow A decreases due to pressure loss, the air flow B also tends to decrease, and the fixing device 15
In some cases, the temperature rise due to the heat radiation of the toner increases, and the dust collection removal function of the toner further deteriorates. However, in the present embodiment, as described above, the toner dust collection and ozone adsorption operations and the air cooling operation of the fixing device 15 do not interfere with each other and adversely affect each other, and the toner dust collection and ozone adsorption are performed. The operation and the air-cooling operation of the fixing device 15 can be effectively performed.

Further, by the outside air suction fan 27,
Since the outside air is sufficiently taken in, the dust collection and ozone adsorption operations are efficiently performed, the temperature rise of the developing device 10 is suppressed, and the toner scattering itself can be reduced.

When the apparatus is in the standby state, the dust collection of toner and the adsorption operation of ozone are stopped to prevent wasteful power consumption, and the fixing device 15 waits at a predetermined standby temperature under low noise. Therefore, a quick response to the fixing operation is always set to be possible.

According to the present embodiment, the high-quality image formation of the original image can be performed by the dust collecting operation of the toner and the adsorption operation of the ozone which do not interfere with each other and the air cooling operation of the fixing device 15. Become.

[0040]

According to the first or second aspect of the present invention, based on the command from the control means, the first exhaust portion provided in the flow path of the air flow including the developing device scatters from the developing device. The toner is collected and ozone is adsorbed and exhausted, and the second exhaust unit provided separately from the first exhaust unit in the flow path of the air flow including the fixing unit cools the fixing unit. The airflow for collecting toner dust and ozone in the developing device and the airflow for cooling the fixing device do not interfere with each other, and the balance of each exhaust operation is not disturbed. Exhaust air for dust collection and ozone adsorption of the scattered toner in the developing device and exhaust air for cooling the fixing device are stably and efficiently performed. According to the invention as set forth in claim 3, in addition to the effect obtained by the invention as set forth in claim 1, since the outside air suction fan is provided at the inlet of the first exhaust part, it is possible to collect dust and ozone. The airflow can be sufficiently obtained from the outside of the apparatus, the efficiency of dust collection and ozone adsorption can be improved, and the temperature rise of the developing device can be suppressed and the toner scattering itself can be reduced. According to the invention of claim 4, claim 1
In addition to the effects obtained by the described invention, the control means stops the operation of the first exhaust unit during the standby operation, so that it is possible to significantly reduce the noise during the standby operation, It is possible to extend the operating life.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing a configuration of an exhaust unit according to an embodiment of the present invention.

FIG. 2 is a perspective explanatory view showing a configuration of a flow path of an exhaust unit of the embodiment.

FIG. 3 is an explanatory diagram showing a configuration of a flow path of an exhaust unit of the embodiment.

FIG. 4 is an explanatory diagram showing a configuration of an exhaust unit of a conventional image forming apparatus.

FIG. 5 is a perspective explanatory view showing a configuration of a flow path of an exhaust unit of a conventional image forming apparatus.

FIG. 6 is an explanatory diagram showing an overall configuration of a conventional image forming apparatus.

[Explanation of symbols]

 1 Scanner Section 9 Photoreceptor Drum 10 Developer 10b Airflow Inlet 10c Airflow Outlet 15 Fixer 20 Duct 21 Ozone Filter 22 Dust Collection Filter 23a Fan 24 Charging Charger 26 Fan 27 Fan for Outside Air Suction

Claims (4)

[Claims] 1. An image of an original image obtained by exposing an original image on an image carrier, developing the obtained electrostatic latent image with a developing device, transferring the obtained toner image onto a transfer paper, and thermally fixing it. An image forming apparatus for forming, which is provided in a flow path of an air flow including the developing device, has a replaceable filter and an exhaust fan, and collects scattered toner from the developing device to exhaust it. A first exhaust unit and an air flow path including the fixing unit are provided separately from the first exhaust unit, and are provided with a cooling fan, and exhaust the cooling unit to the fixing unit. An image forming apparatus comprising: a second exhaust unit that performs the operation; and a control unit that controls operations of the first exhaust unit and the second exhaust unit. 2. The image forming apparatus according to claim 1, wherein the first exhaust part and the second exhaust part are formed separately in a common duct. 3. The image forming apparatus according to claim 1, wherein
An image forming apparatus, wherein an external air suction fan is provided at an inlet of the first exhaust unit. 4. The image forming apparatus according to claim 1, wherein the control unit stops the operation of the first exhaust unit when the operation is on standby.