JPH11282327A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent generation of a trouble such as performance deterioration of an image forming device, its failure, and lowering of its life by carrying out effective cooling and ventilation without accompanying cost-up, size-up, and increased noise, in the image forming device of a type in which a fixing part is arranged in the uppermost portion inside the device, and in which an image forming part and a paper-sheet feeder are arranged in order toward its lower side. SOLUTION: In an image forming device provided with an image forming part B having a photoreceptor 10, developing parts 20, 24, a transfer part 11 and the like, a fixing part 37 arranged in an upper side of the image forming part B, a paper-sheet feeder 33 arranged in a lower side of the part B, and a casing 100 for covering these components, an outside air suction port 101 is provided in the bottom face of the casing 100 an air intake fan 102 is provided in a bottom part inside the casing 100 in the vicinity of the suction port 101 to discharge outside air sucked from the suction port 101 into the casing 100 from an exhaust port 105 provided in a proper position in the casing 100, and a heat-insulation member 110 is interposed between the fixing part 37 and the image forming part B.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a copying machine, a printer,
The present invention relates to an improvement in ventilation and ventilation structure in an electrophotographic image forming apparatus such as a facsimile apparatus, and more particularly, to an image forming apparatus in which a fixing unit is disposed above an image forming unit and an internal cooling and ventilation performance thereof are enhanced. .

[0002]

2. Description of the Related Art In order to reduce the occupied installation area by reducing the plane area of an image forming apparatus, a sheet feeding section has conventionally been arranged at the bottom in an apparatus housing, and an image forming section, The fixing unit is sequentially arranged, and the transfer paper fed from the paper feeding unit is conveyed obliquely upward, so that the image is formed and fixed on the transfer paper. An apparatus configured to discharge paper from a mouth is implemented. In this type of image forming apparatus, when a transfer paper surface (lower side surface) on which an image has been transferred is conveyed obliquely upward toward a fixing unit, the image is disturbed by rubbing against a lower guide plate or the like. A guide plate is not provided below the transfer paper transport path in order to prevent the transfer from occurring. Instead, in order to guide the transfer paper conveyed from the transfer position of the image forming unit into the fixing unit, a transfer fan and a transfer guide are arranged at an upper position of a transfer path between the transfer position and the fixing unit entrance, The transfer fan sucks and transfers the transfer paper toward the transfer guide. That is, by disposing the transport fan and the transport guide on the back surface opposite to the image forming surface of the transfer sheet, the image is prevented from being disturbed due to the rubbing between the image surface and the guide. However, in this type of image forming apparatus,
There has been a problem that heat generated from a fixing unit located at an upper part in a housing adversely affects an image forming part located at a lower part. That is, a unit such as a photoreceptor constituting an image forming unit, a belt, and the like are easily deteriorated by heat, and some electronic components constituting an electrical unit may malfunction or fail due to overheating. In addition, heat from the heat-generating components and units other than the fixing unit raises the temperature inside the device, causing problems such as performance degradation, instability, and shortened life.
In order to prevent such inconveniences, an exhaust fan is provided to take in outside air and exhaust the heated internal air to prevent the temperature inside the device from rising.
It is difficult to prevent a rise in the overall temperature inside the device by providing only one exhaust fan, and increasing the size of the exhaust fan or adding an exhaust fan increases costs, increases size, and increases noise. Bring.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to provide an image forming apparatus in which a fixing unit is arranged at the uppermost part in an apparatus, and an image forming unit and a sheet feeding unit are sequentially arranged downward. An image capable of preventing the occurrence of inconveniences such as performance deterioration, failure, and shortened life of the image forming apparatus by efficiently cooling and ventilating the apparatus without causing cost increase, increase in size, and increase in noise. It is intended to provide a forming apparatus.

[0004]

According to a first aspect of the present invention, there is provided an image forming section including a photoreceptor, a developing section, a transfer section, and the like, and an image forming section disposed above the image forming section. In an image forming apparatus including a fixing unit, a sheet feeding unit disposed below the image forming unit, and a housing that covers these components, an external air suction port is provided on a bottom surface of the housing, and the external air suction port is provided. An intake fan is provided at the bottom of the casing close to the mouth, and the outside air sucked into the casing from the outside air suction port is configured to be exhausted from an exhaust port provided at an appropriate position in the casing. A heat insulating member is interposed therebetween. According to a second aspect of the present invention, the outside air suction port is a louver formed of a small hole or a slit hole formed on a ceiling surface of a recess for a handle provided along two opposing edges of the bottom surface of the housing. Yes, the outside air suction port is concealed in appearance.
According to a third aspect of the present invention, the image forming section has a configuration in which a photoreceptor is arranged on a front side, and a black developing section and a multicolor developing section are arranged in a vertical positional relationship behind the photoreceptor. An exhaust fan is arranged between the photoreceptor and the outside air suction port, an exhaust fan is arranged behind the developing unit constituting the image forming unit, and the air around the image forming unit and its surroundings is sucked by the exhaust fan. It is characterized in that it is configured to exhaust air from an exhaust port on the back of the body. According to a fourth aspect of the present invention, a stay provided for supporting the bottom of the fixing unit to the housing and a heat insulating member are interposed between the fixing unit and the fixing unit and the image forming unit. The fixing unit is isolated from the image forming unit by also blocking the gaps formed by the heat insulating member. According to a fifth aspect of the present invention, a transport fan is disposed along a transfer paper transport path between the image forming section and the fixing section,
The transport fan is surrounded by a duct and discharges air sucked through the duct to the outside. According to a sixth aspect of the present invention, by providing another exhaust fan on the inner wall on the rear surface of the housing, heat from a heat-generating component inside the housing is exhausted to the rear of the housing from an exhaust port provided on the rear surface side. It is characterized by having done.

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to embodiments shown in the drawings. FIG. 1 is a schematic central longitudinal sectional view of a multicolor image forming apparatus according to the present invention. In the figure, reference numeral A denotes an image forming apparatus main body, in which a belt-shaped photoconductor 10 as a first image carrier and a belt-shaped intermediate transfer body (transfer section) as a second image carrier are provided. ) 11 is provided.
The belt-shaped photoconductor 10 is wound around rollers 12 and 13 and is driven to rotate in the direction of arrow a. Then, first, the charging device 14 uniformly charges the surface to a predetermined polarity. Next, the scanning optical device 15 irradiates a laser beam L according to the write information of each color, and forms an electrostatic latent image on the charged surface of the photoconductor 10. In the scanning optical device 15, laser light L from a laser light source (not shown) is
The light is reflected by a polygon mirror 17 rotating at 6, and is emitted out of the apparatus via optical components such as an fθ lens 18 and a mirror 19. The electrostatic latent image formed on the surface of the photoreceptor 10 is sequentially developed by a cyan developing unit 21, a magenta developing unit 22, and a yellow developing unit 23 provided in a multicolor developing unit (developing unit) 20, and then a black toner developing unit ( (Developing unit) 24 to develop a visible image. The multi-color developing device 20 is rotated by a driving device (not shown) so that a developing unit of a desired color is
To face. The black toner developing device 24 comes into contact with the photoconductor 10 by rotating a cam (not shown).

On the other hand, a belt-like intermediate transfer body (transfer section) 1
Reference numeral 1 extends over rollers 27 and 28 and is driven to rotate in the direction of arrow b. Then, the toner image on the photoconductor 10 is successively transferred to the intermediate transfer body 11 by the action of the bias device (transfer section) 30 at a position where the toner image is brought into contact with the photoconductor 10.
For full color, cyan, magenta, yellow,
The black toner images are transferred in a superimposed manner, and the toner images are collectively transferred from the intermediate transfer body 11 to a recording medium (transfer paper) 32 by a transfer roller 31. The recording medium 32 is stacked and stored in the paper feed cassette 33. Then, the sheet is fed out in order from the top by the rotation of the sheet feeding roller 34, conveyed by the conveying roller pair 35, abuts against the registration roller pair 36, and temporarily stopped. The registration roller pair 36 is driven in synchronization with the toner image on the intermediate transfer body 11, and feeds the recording medium 32 toward the intermediate body 11. The recording medium 32 after the image transfer is
The sheet is conveyed to a fixing device (fixing section) 37, where the transferred image is fixed by heat and pressure. Then, the discharge roller pair 3
At 8, the sheets are discharged onto the scarlet stack section 39 in page order with the image recording surface facing down. 1, the electrical equipment / control device 57 is provided on the left side in FIG. 1, and an exhaust fan (other exhaust fan) 58 is provided on the rear surface of the housing. The exhaust fan 58 is driven appropriately to exhaust air, and prevents the temperature inside the apparatus main body A from rising. The right side in the figure is the front of the apparatus main body A, and an operation panel 61 for operation and display is provided on the front. In the illustrated multicolor image forming apparatus, as shown in FIG. 2, the upper surface of the recording medium 32 after image transfer is placed between the transfer roller 31 (not shown in FIG. 2) and the fixing device 37 in the apparatus main body A. Conveying guide 63 in contact with
And a transport fan 64 supported by the transport guide 63 and located above the transport fan. Further, a shielding plate is provided between the transport fan 64 and the operation panel 61 as necessary. Transport fan 64
Is surrounded by a duct 116, and an ozone filter 117 is arranged in the duct as necessary. The inside opening of the duct 116 is directed to the transfer sheet transport path, and the other end opening is through the upper portion of the fixing device 37 and is located at the upper side of the discharge port of the exhaust port 118.
In communication with When the recording medium 32 is transported,
The transport fan 64 is controlled by control means provided in the
Is driven, and the recording medium 32 after the image transfer is sucked and made to follow the conveyance guide 63, and guided by the conveyance guide 63 to guide the recording medium 32 after the image transfer to the fixing device 37.

After a series of image recording operations, the recording medium 32
Is completed, the control means provided in the electrical equipment / control device 57 drives the transfer fan 64 to block the flow of air.
5, an air circulation path is formed in the apparatus main body A as indicated by an arrow in FIG. At this time, the transport fan 64 is driven at a rotation speed of 1/2 to 1/4 during the transport, and circulates the air flow in the apparatus main body A at the same level as convection or slightly faster. If the transport fan 64 is always turned on when the recording medium 82 is not transported, the temperature on the operation panel 61 side increases.
Every time you turn on for 5 to 1.0 hours, turn off for 1.0 hour,
Turn off periodically. Further, when the recording medium 32 is not conveyed, the conveyance fan 64 may be appropriately rotated in the reverse direction by the control means to circulate the air in the apparatus main body A in the reverse direction. In this type of image forming apparatus, when the transport fan 64 is driven only when the recording medium 32 is transported as in the related art, the temperature around the operation panel 61 rises only to about 39 ° C. The surrounding temperature had reached 63 ° C. However, if the transport fan 64 is turned on and off even when the recording medium 32 is not transported as in the present invention, the operation panel 6
By setting the temperature around 1 to 43 ° C. and the temperature around the fixing device 37 to 45 ° C., the temperature inside the apparatus main body A can be suppressed to 45 ° C. or less to achieve a balance.

Next, the characteristic structure of the present invention will be described in more detail. First, according to the present invention, as shown in FIG.
0, an image forming unit B including developing devices 20 and 24, transfer devices 11 and 31, a fixing device (fixing unit) 37 disposed above the image forming unit B, and a fixing device 37 below the image forming unit B. The paper feed unit 33 disposed and the housing 10 that covers these components
The characteristic of the image forming apparatus is that an outside air suction port 101 is provided on the bottom surface of the housing 100, and an intake fan 102 is provided on the bottom inside the housing close to the outside air suction port 101. The point is that outside air sucked into the housing from the suction port 101 is exhausted from an exhaust port 105 provided at an appropriate position in the housing. Another characteristic is that the conveying fan 64 covered by the duct 116 is also used for exhaust, and the heat from the fixing unit is exhausted from the exhaust port at the top of the housing. This outside air suction port 101 is, for example, as shown in FIG.
As shown in the perspective view of (b), the device is formed on the ceiling surface of the recess 106 for the handle formed along the left and right bottom sides when viewed from the front. The recess functions as a handle for transporting the equipment, and introduces outside air into the machine from an outside air suction port (louver) formed of a small hole, a slit, or the like provided on the ceiling surface of the recess. By arranging the intake fan 102 between one outside air suction port 10 and the image forming unit, particularly at a position directly below the photoreceptor 10, the ability to suction outside air from the suction port 101 can be promoted. The recess 106 for the handle is, of course, located at a position avoiding the sheet feeding section 33, that is, on both sides of the sheet feeding section. By configuring the outside air suction port with small holes, slits, and the like, a filter effect can be exhibited. In addition, a filter may be disposed in the outside air suction port 101 as necessary to reliably prevent foreign matter from entering. Since the outside air suction port 101 is located inside the recess (ceiling surface, inner wall, etc.), it cannot be distinguished from the appearance. Suction fan 10
Reference numeral 2 also functions to exhaust the ozone generated from the charger 14.

Next, in the present invention, the heat from the fixing unit affects the image forming unit by interposing the heat insulating member 110 between the image forming unit B and the fixing unit 37 located immediately above the image forming unit B. Is preventing that. Specifically, for example, a sheet in which glass fiber and aluminum foil are laminated is used as the heat insulating member, and the heat insulating member is placed in a state where the aluminum foil surface faces the lower surface of the fixing unit (a stay supporting the lower surface of the fixing unit). And the heat insulating member 110 is also arranged in a gap communicating the fixing section and the image forming section to block the flow of air. The reason for directing the aluminum surface toward the fixing unit is that radiant heat can be minimized by such a configuration.
Also, the heat insulating effect can be enhanced by disposing the aluminum surface with a certain gap rather than by closely attaching the aluminum surface to the lower surface of the fixing unit (the lower surface of the stay). As described above, the outside air sucked from the bottom of the apparatus is discharged to the rear after passing through the image forming section, and the fixing section 37 and the image forming section B are shut off by the heat insulating member 110. Since it can be divided into a medium temperature section and a high temperature section, natural convection is brought into the machine, and a rise in temperature can be suppressed. Further, when replacing the supply and performing work with the front cover opened, the safety of the worker can be ensured by the heat insulating effect.

The image forming section includes a photosensitive member 1 in front of the apparatus.
0, a black developing unit (black developing unit) 24 and a multi-color developing unit (multi-color developing unit),
20 is disposed, but an exhaust fan 115 is provided behind the developing units 24 and 20 forming the image forming unit.
Are arranged, and the air around the image forming section and its surroundings is sucked by the exhaust fan 115 and then exhausted from the exhaust port 105 on the rear surface of the housing. Therefore, after the airflow formed by the intake fan 102 carries heat from a heat source, ozone, toner, etc., the exhaust fan 115
Is discharged from the exhaust port 105 to the outside of the apparatus. Exhaust port 10
5 is provided with an ozone filter and other filters as necessary. As described above, the exhaust fan 115 is provided on the back surface of the image forming unit, and the stirring can be performed by the exhaust fan. Therefore, an airflow is formed around the image forming unit, and the internal temperature can be prevented from rising. In addition, the moving direction of the floating toner generated from the image forming unit can be restricted to one direction, and the adhesion to the transfer paper or the like can be prevented.

Next, in this embodiment, one or a plurality of transport fans 64 are arranged along the transfer paper transport path between the image forming section and the fixing section 37.
Is configured to be surrounded by a duct 116 and discharge the air sucked through the duct 116 to the outside of the machine through a flow path indicated by an arrow. A filter 117 such as an ozone filter is disposed in the duct as needed. The transport fan 64 is provided with a transfer paper suction guide,
Exhaust air between transfer sheets and cooling during standby are performed. For cooling during standby, a rotation speed of about の of the rotation speed during transport is sufficient. Further, ON and OFF of the transport fan 64 are arbitrary, and the rotation direction can be changed. In the present embodiment, the exhaust fan 58 is provided on the inner wall on the rear surface of the housing 100, so that heat from the heat-generating components inside the housing is exhausted to the rear of the housing from the exhaust port 105 provided on the rear surface. As a result, heat from a power supply, a motor, etc. is exhausted to the rear of the apparatus, and the operator is exhausted (high temperature, dust, odor (C0
₃ ) It is possible to collectively exhaust airflow backward so that airflow does not hit.

[0012]

As described above, according to the present invention, there is provided an image forming apparatus of a type in which a fixing unit is arranged at the uppermost part inside a device, and an image forming unit and a sheet feeding unit are sequentially arranged downward.
Efficient cooling and ventilation can be performed without causing a cost increase, an increase in size, and an increase in noise, thereby preventing problems such as performance deterioration, failure, and shortened life of the image forming apparatus. That is, according to the first aspect of the present invention, the outside air sucked from the bottom of the device passes through the image forming unit and is discharged to the rear, and the fixing unit and the image forming unit are shut off by the heat insulating member. Since it can be divided into a low-temperature part, a medium-temperature part, and a high-temperature part, natural convection can be brought into the machine, and a rise in temperature can be suppressed. The invention according to claim 2 is provided with an outside air suction port also serving as a handle on the bottom surface of the device,
External low-temperature air can be taken into the machine, and temperature rise inside the machine can be effectively prevented. In addition, the outside air suction port is a small hole,
By using a slit or the like, a filter effect can be exhibited. According to the third aspect of the present invention, an exhaust fan is provided on the back of the image forming unit, and the exhaust fan can agitate the air. Also, the moving direction of the floating toner generated from the image forming unit can be regulated in one direction,
Adhesion to transfer paper or the like can be prevented. In the invention of claim 4,
By disposing the heat insulating member on the bottom of the fixing unit or on the stay supporting the bottom of the fixing unit, it is possible to prevent heat from the fixing unit serving as a heat source from being radiated to the image forming unit. Further, when replacing the supply and performing work with the front cover opened, the safety of the worker can be ensured by the heat insulating effect.
According to the fifth aspect of the present invention, since the conveying fan is covered with the duct, the effect of exhausting air from the upper part of the apparatus can be enhanced, and the temperature of the cover and the like can be prevented from rising. In the invention of claim 6, by directing the exhaust air direction from the internal device to the device back side, temperature, dust, that the odor (C0 ₃₎ or the like strikes the direct operator eliminated.

[Brief description of the drawings]

FIG. 1 is a side longitudinal sectional view of an image light diameter device according to an embodiment of the present invention.

FIGS. 2A and 2B are external perspective views of the image forming apparatus of FIG.

[Explanation of symbols]

A image forming apparatus main body, B image forming section, 10 photoreceptor, 11 intermediate transfer body (transfer section), 12, 13 roller, 14 charging device, 15 scanning optical device, 16 motor, 17 polygon mirror, 20 multicolor developing device (Developing unit), 21 cyan developing unit, 22 magenta developing unit, 23 yellow developing unit, 24 black toner developing unit (developing unit), 27 and 28 rollers, 30 bias device (transfer unit), 31 transfer roller, 32 recording medium (Transfer paper), 33 paper cassette, 34 paper feed roller, 35 transport roller pair, 36 registration roller pair, 3
7 fixing device (fixing unit), 38 paper discharge roller pair, 39 scarlet paper stack unit, 57 electrical equipment and control device, 58 exhaust fan (other exhaust fan), 61 operation panel,
63 transport guide, 100 housing, 101 outside air suction port, 102 intake fan, 105 exhaust port, 106 recess, 110 heat insulating member, 116 duct, 117 ozone filter.

Claims (6)

[Claims] An image forming unit including a photoreceptor, a developing unit, a transfer unit, and the like; a fixing unit disposed above the image forming unit;
An image forming apparatus comprising: a sheet feeding unit disposed below an image forming unit; and a housing that covers these components. In the image forming apparatus, an external air suction port is provided on a bottom surface of the housing, and the external air suction port is provided near the external air suction port. An intake fan is provided at the bottom of the housing, and the outside air sucked into the housing from the outside air suction port is exhausted from an exhaust port provided at an appropriate position in the housing, and a heat insulating member is provided between the fixing unit and the image forming unit. An image forming apparatus comprising: 2. The outside air suction port is a louver comprising a small hole or a slit hole formed in a ceiling surface of a recess for a handle provided along two opposing edges of a bottom surface of the housing, 2. The image forming apparatus according to claim 1, wherein the outside air suction port is concealed in appearance. 3. The image forming section has a configuration in which a photoreceptor is disposed on a front side, and a black developing section and a multicolor developing section are disposed in a vertical positional relationship behind the photoreceptor. And an outside air suction port, an exhaust fan is arranged behind the developing unit constituting the image forming unit, and the air around the image forming unit and its surroundings is sucked by the exhaust fan. 3. The image forming apparatus according to claim 1, wherein air is exhausted from an exhaust port on a back surface. 4. A gap provided between the stay provided to support the bottom of the fixing unit to the housing and a heat insulating member between the fixing unit and the fixing unit and the image forming unit. The image forming apparatus according to claim 1, wherein the fixing unit is separated from the image forming unit by also shielding the fixing unit with a heat insulating member. 5. A transport fan is disposed along a transfer paper transport path between the image forming unit and the fixing unit, and the transport fan is surrounded by a duct and removes air sucked through the duct. 5. The image forming apparatus according to claim 1, wherein the image is discharged outside. 6. An arrangement in which another exhaust fan is provided on the rear surface of the housing, so that heat from a heat-generating component inside the housing is exhausted to the rear of the housing from an exhaust port provided on the rear surface side. The image forming apparatus according to claim 1, 2, 3, 4, or 5, wherein