JP2014160118A - Image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming apparatus which reduces cost by eliminating a filter while reducing ozone to be discharged, and achieves energy saving and noise reduction.SOLUTION: An image forming apparatus includes: a temperature sensor 215 which detects temperature in a casing; and a control unit 200 that controls operation driving speed which are rotation driving speed of fans during printing operation, and reduces the operation driving speed of the fans as compared with a case of exceeding a predetermined first threshold when the temperature is equal to or lower than the first threshold.

Description

  The present invention relates to an ozone removal fan for exhausting the air inside the enclosure outside the enclosure while passing through a filter capable of removing ozone, and non-ozone for exhausting the air inside the enclosure outside the enclosure without passing through the filter. The present invention relates to an image forming apparatus including a removal fan.

  2. Description of the Related Art Conventionally, an image forming apparatus such as a copying machine, a facsimile machine, or a printer is known as disclosed in Patent Document 1. This image forming apparatus is a fixing device for thermally fixing a toner image formed on a recording sheet by a well-known electrophotographic process to the recording sheet, and discharges the air inside the apparatus heated by the fixing device to the outside of the apparatus. It has an exhaust fan and so on. In the electrophotographic process, ozone is generated in a process of uniformly charging the photosensitive member. Therefore, when an ordinary exhaust fan is used, ozone inside the apparatus is discharged outside the apparatus, causing various problems. For this reason, in the image forming apparatus described in Patent Document 1, an exhaust fan equipped with a filter capable of removing ozone is used, and the air inside the apparatus is discharged outside the apparatus while passing through the filter. It is designed to suppress ozone leakage.

  In a relatively small image forming apparatus, it is possible to sufficiently reduce the temperature inside the apparatus with a single exhaust fan. However, in a relatively large image forming apparatus, an exhaust fan is not provided in various places of the housing. It may be difficult to reduce the temperature sufficiently in some parts of the aircraft. Therefore, in a relatively large image forming apparatus, a plurality of exhaust fans are generally provided in the casing. Among a plurality of exhaust fans, an image forming apparatus in which a filter is not provided for an exhaust fan that exhausts air at a position relatively away from an ozone generation source such as a charging device has been put into practical use. In an exhaust fan that exhausts air at a relatively distant position from the ozone generation source, ozone is hardly sucked, so that the cost can be reduced by omitting the filter.

  However, this image forming apparatus has a problem that wasteful energy is consumed or wasteful noise is generated. Specifically, the temperature inside the apparatus does not increase so much when an image is output on only one sheet of paper or when an image is output on a plurality of sheets at the beginning of operation. Nevertheless, since the plurality of exhaust fans are each driven to rotate at a sufficient speed, useless energy consumption and useless noise are generated.

  The present invention has been made in view of the above background, and the object of the present invention is to reduce the cost by omitting a filter while suppressing emission of ozone, and to achieve energy saving and noise reduction. It is an object of the present invention to provide an image forming apparatus capable of performing the above.

  To achieve the above object, the present invention provides a visible image forming means for forming a visible image on a recording member, a housing containing the visible image forming means, and an ozone generation source of the visible image forming means. An ozone removal fan that is an exhaust fan for exhausting air existing near the outside of the housing while passing through a filter capable of removing ozone, and a position relatively distant from the ozone generation source in the housing In an image forming apparatus comprising a non-ozone removing fan that is an exhaust fan for exhausting air outside the housing without passing through the filter, temperature detecting means for detecting the temperature inside the housing, and the visible image formation The operating driving speed, which is the rotational driving speed of the ozone removing fan or the non-ozone removing fan during the operation of the means, is controlled, and the detection result by the temperature detecting means is a predetermined first value. When the threshold value is less than the threshold value or less than the first threshold value, the operating drive speeds of the ozone removal fan and the non-ozone removal fan are respectively slowed as compared with the case where the first threshold value is exceeded or the threshold value is exceeded. Fan control means for performing processing is provided.

  In the present invention, the air existing near the ozone generation source of the visible image forming means is discharged outside the casing while passing through a filter having an ozone removing capability by an ozone removing fan, so that the ozone to the outside of the casing is discharged. Emission can be suppressed.

  Further, in the present invention, the filter is omitted for the exhaust fan for exhausting air that has a high possibility of not containing ozone because it is located at a position relatively away from the ozone generation source in the housing. Cost reduction can be achieved by using a non-ozone removing fan.

  Further, in the present invention, when the temperature of the air in the enclosure is equal to or lower than the first threshold value or lower than the first threshold value (when the necessity for exhaust is low), the ozone removing fan is compared with the case where the necessity for exhaust is high. Reduce the drive speed when operating the non-ozone removal fan. Since the operating speed of the two fans is slowed down, energy saving and low noise are achieved while preventing the generation of ozone exhaust by the non-ozone removing fan due to slowing down of the operating speed of the ozone removing fan only. Can be achieved.

1 is a schematic configuration diagram showing a copier according to an embodiment. FIG. 2 is an enlarged configuration diagram showing a process cartridge of the copier. 1 is a perspective view showing a copying machine according to an embodiment. FIG. 3 is a perspective view showing a drawer unit of the copier. FIG. 2 is a schematic configuration diagram showing the copier in a state where the drawer unit is pulled out. (A) is a disassembled perspective view showing a partly disassembled state of the drawer unit, and (b) is a partial perspective view partially showing the drawer unit. The perspective view which shows the back plate of the front cover of the drawer unit. FIG. 2 is a perspective view showing a shielding plate of the copier together with its peripheral configuration. FIG. 2 is a perspective view showing the copier from an obliquely rear side. FIG. 2 is a perspective view showing an internal framework of the copier and various internal devices from an oblique rear side of the copier. The perspective view which shows a 1st filter from diagonally forward. The perspective view which shows the 1st filter from the diagonal publication. FIG. 3 is a perspective view showing equipment related to an ozone exhaust system in an image forming unit of the copier together with a reverse exhaust fan. The perspective view which shows the apparatus relevant to the paper discharge back surface ozone removal fan in the housing | casing of the image formation part, and the heat radiation development ozone removal fan. The perspective view which shows the apparatus in the state which remove | excluded two filters. The perspective view which shows the apparatus relevant to the development exhaust fan in the same housing. The perspective view which shows the apparatus relevant to the main ozone exhaust fan in the same housing. The perspective view which shows the apparatus relevant to the belt and fixing exhaust system in the same housing. FIG. 3 is a block diagram showing a part of an electric circuit in the image forming unit. 3 is a flowchart showing a processing flow of fan drive control processing executed by a control unit of the copier.

  Hereinafter, an embodiment in which the present invention is applied to a copying machine as an image forming apparatus will be described. First, an outline of the copying machine will be described with reference to FIG. This copier has a function as a so-called digital color copier that digitizes image information obtained by scanning and reading a document and uses it for image formation. The copying machine also has a facsimile function for transferring image information of a document to a remote place, and a so-called printer function for printing image information handled by a computer on paper.

  In FIG. 1, a copying machine forms an image on a recording sheet by an intermediate transfer method using an intermediate transfer belt 11, and uses a tandem method in which each color toner image is formed by a dedicated process cartridge. An electrophotographic apparatus. A multi-stage sheet feeding unit 2 is provided at the lowest part in the vertical direction of the copying machine. In addition, an image forming unit 1 is provided above, and a scanner unit 3 is provided for the information. In each stage of the paper feed unit 2, a paper feed tray 21 is disposed that accommodates a sheet bundle composed of recording sheets such as plain paper as a recording member, an OHP sheet, and a second original drawing.

  Near the center of the image forming unit 1, there is disposed a transfer device 10 in which an endless intermediate transfer belt 11 is stretched by a plurality of rollers disposed inside the belt loop. The intermediate transfer belt 11 rotates (surface moves) in the clockwise direction in the drawing. Above the intermediate transfer belt 11, four process cartridges 40Y, 40M, 40C, and 40K for forming yellow, magenta, cyan, and black toner images are arranged along the surface movement direction of the intermediate transfer belt 11. It is installed. Hereinafter, Y, M, and C that are color-coded codes are omitted as appropriate.

  Each process cartridge 40 is provided with a drum-shaped photoconductor 41 as a latent image carrier. Each photoconductor 41 is provided so as to be rotatable in the counterclockwise direction in the drawing, and a known charging device 42, a developing device 43, a primary transfer device 46 constituting a primary transfer means, and a photosensitive member are disposed around the photoconductor 41. A body cleaning device 44 and a lubricant application device 45 are provided. Above the four process cartridges 40, two optical writing units 20a and 20b are provided as latent image writing means.

  FIG. 2 is an enlarged configuration diagram illustrating the developing device 43 and the photosensitive member 41 in one of the four process cartridges 40Y, 40M, 40C, and 40K. While the photoconductor 41 rotates counterclockwise in the drawing, the surface thereof is uniformly charged by a charging device (not shown) (42 in FIG. 1). The surface of the uniformly charged photoreceptor 41 carries an electrostatic latent image by laser light irradiated by an optical writing unit (not shown) (20a, 20b in FIG. 1). The electrostatic latent image is developed by the developing device 43 to become a toner image.

  The developing device 43 has a developing roller 43a as a developer carrying member for developing the latent image by supplying toner to the latent image on the surface of the photoreceptor 1 while moving in the direction of arrow I in the drawing. Further, a supply screw 43b is provided as a supply conveying member that conveys the developer from the back side in the direction orthogonal to the drawing sheet to the front side while supplying the developer to the developing roller 5. The supply screw 43b includes a rotation shaft and a wing portion provided on the rotation shaft, and conveys the developer in the axial direction by rotating.

  A developing doctor 43c as a developer regulating member that regulates the developer on the developing roller 43a to a thickness suitable for development is provided downstream of the developing roller 43a and the supply screw 43b in the moving direction of the developing roller surface. Is provided. Further, a recovery screw 43d for recovering the developed developer that has passed through the development area is provided downstream of the development area, which is the area where the development roller 43a and the photoconductor 41 are opposed, in the movement direction of the development roller. . The collection screw 43d conveys the collected developer collected from the developing roller 43a in the same direction as the supply screw 43b. The supply conveyance path 43e that accommodates the supply screw 43b is disposed on the side of the developing roller 43a. In addition, a recovery conveyance path 43f as a developer recovery conveyance path that accommodates the recovery screw 43d is arranged in parallel below the developing roller 43a.

  The developing device 43 has an agitation conveyance path 43g for agitating and conveying the developer in a direction parallel to the recovery conveyance path 43f below the supply conveyance path 43e. The agitation conveyance path 43g has an agitation screw 43h that conveys the developer in a direction opposite to the supply screw 43b while stirring the developer.

  The supply conveyance path 43e and the agitation conveyance path 43g are partitioned by a first partition wall. In the first partition wall, the supply conveyance path 43e and the agitation conveyance path 43g are partitioned at both ends on the front side and the back side in the drawing, and the supply conveyance path 43e and the agitation conveyance path 43g communicate with each other. ing. Note that the supply conveyance path 43e and the recovery conveyance path 43f are both partitioned by the first partition wall, but no opening is provided in the first partition wall where the supply conveyance path 43e and the recovery conveyance path 43f are partitioned. . Further, the two conveyance paths of the stirring conveyance path 43g and the collection conveyance path 43f are partitioned by the second partition wall. The second partition wall has an opening on the front side in the figure, and the stirring conveyance path 43g and the collection conveyance path 43f communicate with each other.

  The developer on the developing roller 43a is thinned by the developing doctor 43c, and is then transported to a developing region that is a region where the photosensitive member 41 faces the developing roller 43a, thereby contributing to development. The developer after development is collected in the collection conveyance path 43f, and then conveyed from the back side in the direction orthogonal to the drawing sheet to the near side, and through the opening provided in the second partition wall, the stirring conveyance path Enter 43g. The toner is replenished into the stirring and conveying path 43g from the developer supply port provided on the upper side of the stirring and conveying path 43g near the opening of the second partition wall at the upstream end in the developer conveying direction in the stirring and conveying path 43g. Is done.

  In the supply conveyance path 43e that receives the developer supplied from the agitation conveyance path 43g, the developer is supplied to the developing roller 43a while the supply screw 43b supplies the developer near the most downstream side in the developer conveyance direction of the supply conveyance path 43e. Transport. Then, the excess developer that is supplied to the developing roller 43a and is not used for development and is transported to the vicinity of the most downstream in the developer transport direction of the supply transport path 43e is supplied to the stirring transport path 43g through the surplus opening of the first partition. .

  The recovered developer fed from the developing roller 43a to the recovery conveyance path 43f and conveyed by the recovery screw 43d to the vicinity of the most downstream side of the recovery conveyance path 43f in the developer conveyance direction passes through the recovery opening of the second partition wall to the agitation conveyance path 43g. Supplied. The agitation transport path 43g is near the most downstream side in the developer transport direction of the agitation transport path 43g with the stirring screw 43h while stirring the supplied surplus developer and the recovered developer, and the supply transport path 43e. Transport to a position near the most upstream side in the developer transport direction. The developer transported to such a position enters the supply transport path 43e through the supply opening of the first partition wall.

  In the agitation conveyance path 43g, the agitated screw 43h supplies the collected developer, the surplus developer, and the toner replenished as necessary from the developer replenishment port in a direction opposite to the developer in the collection conveyance path 43f and the supply conveyance path 43e. Transport with stirring. Then, the agitated developer is transferred to the vicinity of the most upstream side in the developer transport direction of the supply transport path 43e communicating in the vicinity of the most downstream side in the developer transport direction.

  A toner concentration sensor 43j is provided in the vicinity of the supply opening near the most downstream side in the developer conveyance direction of the stirring conveyance path 43g. In accordance with the output from the toner concentration sensor 43j, a toner replenishment control device (not shown) is driven and replenished into the agitation transport filter 43g.

  In FIG. 1, the transfer device 10 has a secondary transfer device 22 constituting a secondary transfer unit below the intermediate transfer belt 11. The secondary transfer device 22 is in pressure contact with the secondary transfer counter roller 16 via the intermediate transfer belt 11. Then, the secondary transfer device 22 performs a secondary transfer of the toner image on the intermediate transfer belt 11 to a recording sheet fed between itself and the intermediate transfer belt 11. A belt cleaning device 17 is provided downstream of the secondary transfer counter roller 16 in the direction of surface movement of the intermediate transfer belt 11. Residual toner remaining on the surface of the intermediate transfer belt 11 after image transfer by the belt cleaning device 17. Is removed. Further, the belt cleaning device 17 includes a lubricant application mechanism, and applies a lubricant to the surface of the intermediate transfer belt 11.

  A fixing device 25 that fixes the toner image formed on the recording sheet on the sheet surface is provided downstream of the secondary transfer device 22 in the paper conveyance direction. A pressure roller 27 is pressed against the endless fixing belt 26. The recording sheet after image transfer is conveyed to a fixing device 25 by an endless conveying belt 24 that is stretched between a pair of rollers 23. A sheet reversing device 28 is provided below the secondary transfer device 22 for reversing the sheet when images are formed on both the front and back sides of the sheet.

  When copying a color original with the copying machine having the above-described configuration, the scanner unit 3 reads an image of the original set on the contact glass. Further, the intermediate transfer belt 11 is rotated to form a toner image on each photoconductor 41 by a known image forming process. Next, the toner images formed on the respective photoreceptors are sequentially superimposed and primarily transferred to the intermediate transfer belt 11 to form a four-color superimposed toner image on the intermediate transfer belt 11.

  On the other hand, in parallel with the image forming operation of the four-color superimposed toner image on the intermediate transfer belt 11, the recording sheets are separated and fed one by one from the selected paper feed tray 21 of the paper feed unit 2, and the registration rollers 29. Transport toward The separated and transported recording sheet abuts on the nip of the registration roller 29 and is temporarily stopped after transporting. The registration roller 29 is driven to rotate at a timing so that the positional relationship between the four-color superimposed toner image formed on the intermediate transfer belt 11 and the leading edge of the recording sheet is a predetermined position. Due to the rotation of the registration roller 29, the waiting recording sheet is fed again. As a result, the four-color superimposed toner image on the intermediate transfer belt 11 is secondarily transferred to the predetermined position of the recording sheet by the secondary transfer device 22 to form a full-color toner image on the recording sheet.

  The recording sheet on which the full-color toner image is formed in this manner is sent to the fixing device 25 located downstream of the secondary transfer device 22 in the conveyance path. The fixing device 25 fixes the full color toner image secondarily transferred by the secondary transfer device 22 on the recording sheet. The recording sheet on which the full-color toner image is fixed is discharged out of the apparatus by a discharge roller 30. In a double-sided print mode in which images are formed on both sides of a recording sheet, when a recording sheet having a full-color toner image fixed only on the first side is discharged from the fixing device 25, the recording sheet is not the discharge roller 30. , And sent to the sheet reversing device 28. Then, after the front and back surfaces are reversed by the sheet reversing device 28, they are conveyed again to the registration rollers 29. Thereafter, a full-color image is also formed on the second surface through the secondary transfer device 22 and the fixing device 25.

  In the copying machine having the above configuration, a visible image that forms a toner image as a visible image on a recording sheet by the optical writing units 20a and 20b, the process cartridges 40Y, 40M, 40C, and 40K, the transfer device 10, and the like. Forming means are configured. The copier slides in and out of the copier housing in a state where the secondary transfer device 22, the fixing device 25, the sheet reversing device 28, and the paper discharge path are integrally held. A drawer unit is provided.

  FIG. 3 is a perspective view showing the copying machine according to the embodiment. In the drawing, the drawer unit 76 includes a secondary transfer device 22, a fixing device 25, a sheet reversing device 28, and a carrier 71 that holds a paper discharge path. A front cover 79 is attached to the carrier 71. The carrier 71 is slidably held in the front-rear direction (arrow FR in FIG. 3) with respect to the image forming unit 1 by a rail 72 provided in the apparatus main body. The user holds the handle 79 a provided on the front cover 79 and pulls or pushes the front cover 79 in the front-rear direction with respect to the image forming unit 1, thereby pulling the drawer unit 76 out of the image forming unit 1. And can be stored.

  The front side F of the image forming unit 1 means the front side of the image forming unit 1, and the rear side R means the back side of the image forming unit 1.

  When the copying machine is used, the drawer unit 76 is accommodated in the image forming unit 1, while each apparatus held in the drawer unit 76 is replaced or when paper jammed in each conveyance path is removed. Pulls out the drawer unit 76 to the front side F with respect to the image forming unit 1. As a result, it is possible to replace each device held in the drawer unit 76 and remove the paper jammed in each conveyance path.

  FIG. 4 is a perspective view showing the drawer unit 76. In the drawing, the front cover 79 has an outer cover portion 79b that is exposed to the outside even when the drawer unit 76 is pushed into the image forming portion. Further, it also has an inner cover portion 79c exposed to the outside only when the drawer unit 76 is pulled out from the image forming portion.

  FIG. 5 is a schematic configuration diagram showing the copying machine with the drawer unit 76 pulled out. As shown in the figure, even when the drawer unit 76 is pulled out, the intermediate transfer belt 11, the process cartridges 40Y, 40M, 40C, and 40K for each color, the optical writing units 20a and 20b, and the like remain in the casing of the image forming unit 1. It is.

  FIG. 6A is an exploded perspective view showing a partly exploded state of the drawer unit 76, and FIG. 6B is a partial perspective view partially showing the drawer unit. The front cover 79 is screwed to the drawer unit front plate 78 so that it cannot be removed without using a tool. By fixing the front cover 79 to the drawer unit 76 in this way, the drawer unit 76 can be pulled out simply by pulling out the front cover 79.

  FIG. 7 is a perspective view showing the back plate 79 d of the front cover 79. On the front side of the back plate 79d, a front plate (not shown) of the front cover 79 is opposed to the back plate 79d with a predetermined gap. A handle 79a gripped when the front cover 79 is pulled is disposed between the back plate 79d and the front plate as shown in the figure. Of the entire region in the surface direction of the back plate 79d, an intake louver 79e for taking outside air into the housing of the image forming unit is formed in an area surrounded by the handle 79a. Outside air passes through the mesh of the louver 79e and enters the housing of the image forming unit.

  In the vertical direction of FIG. 1, a shielding plate 60 for shielding hot air generated in the fixing device 25 is disposed between the intermediate transfer belt 11 and the fixing device 25. The shielding plate 60 receives hot air generated in the fixing device 25 and prevents the intermediate transfer belt 11 and the process cartridge 40 from being raised to the position of the intermediate transfer belt 11 and the process cartridge 40, thereby suppressing the temperature rise of the intermediate transfer belt 11 and the process cartridge 40. Is responsible.

  FIG. 8 is a perspective view showing the shielding plate 60 together with its peripheral configuration. The shielding plate 60 includes a heat receiving part 60a that receives hot air in a posture extending in the horizontal direction, and a heat exchange part 60b that rises obliquely upward from one end of the heat receiving part 60a. The heat receiving portion 60a extending in the horizontal direction is disposed directly above the fixing device 25, and receives the heat generated from the fixing device 25 to take the heat.

  A plurality of heat pipes 61 are fixed to the surface of the shielding plate 60 in a posture extending from the heat receiving portion 60a to the heat exchanging portion 60b. The heat of the heat receiving portion 60 a heated by receiving hot air is transmitted to one end portion in the longitudinal direction of the heat pipe 61. Then, the heat exchange medium accommodated in one end portion in the longitudinal direction of the heat pipe 61 is heated to change from a liquid state to a gas state. And the inside of the area | region currently wound around the surface of the heat exchange part 60b of the shielding board 60 among the whole areas of the heat pipe 61 rises. A heat sink 65 for promoting heat dissipation is connected to the upper end of the heat pipe 61. The heat exchange medium in the gas state that has risen in the heat pipe 61 is cooled in the heat sink 65, thereby changing from a gas state to a liquid state. Then, conversely, the heat pipe 61 is lowered and returned to just above the heat receiving portion 60 a of the shielding plate 60.

  A fixing cooling fan 62 is disposed in front of the heat sink 65. The fixing cooling fan 62 promotes heat radiation from the heat sink 65 by blowing air toward the heat sink 65.

  FIG. 9 is a perspective view showing the copying machine according to the embodiment from an obliquely rear side. In the drawing, a first louver 151, a second louver 152, a third louver 153, and a fourth louver 154 are arranged in order from the upper side to the lower side in the vertical direction on the back plate of the housing 1a of the image forming unit 1. Is provided. A fifth louver 155 is provided on the side plate of the housing 1a. Each of these louvers is for discharging the air in the housing 1a to the outside.

  FIG. 10 is a perspective view showing the internal framework of the copying machine and the various devices in the copying machine according to the embodiment from an oblique rear side of the copying machine. In a housing (not shown) of the copying machine, three reversing exhaust fans 81 are arranged in order in the front-rear direction of the copying machine in a space near the left end of the copying machine body. These reversing exhaust fans 81 are exhausted outside the housing through the fifth louver 155 shown in FIG. 9 while sucking the air present in the vicinity of the sheet reversing device 28 shown in FIG. The temperature in the vicinity of the sheet reversing device 28 is lowered. Since the sheet reversing device 28 is temporarily driven only in the duplex printing mode, the amount of heat generated is not so large. Therefore, the frequency with which exhaust by the reversing exhaust fan 81 is required is not so high.

  In the copying machine according to the embodiment, the charging devices (42Y, 42M, 42C, 42K) of the process cartridges (40Y, 40M, 40C, 40K) of the respective colors are the main ozone generation sources. Since the sheet reversing device 28 is located relatively far from these charging devices, the air present in the vicinity of the sheet reversing device 28 contains almost no ozone. For this reason, the air sucked by the reversing exhaust fan 81 is discharged out of the apparatus through the fifth louver 155 without passing through a filter for removing ozone. In such a configuration, it is possible to reduce the cost by omitting a filter for removing ozone from the air sucked into the reversing exhaust fan 81.

  In a housing (not shown), the first filter 161, the second filter 162, the third filter 163, and the fourth filter 164 are arranged in order in the vertical direction from the top to the bottom in the space near the end on the back side. It is installed. The first filter 161 is disposed at a position facing the first louver 151 shown in FIG. Further, the second filter 162, the third filter 163, and the fourth filter 164 are disposed at positions facing the second louver 152, the third louver 153, and the fourth louver 154. Each of these filters is for removing ozone.

  FIG. 11 is a perspective view showing the first filter 161 obliquely from the front. FIG. 12 is a perspective view showing the first filter 161 from an oblique publication. As shown in these drawings, the first filter 161 holds a breathable filter material 161b in a cage-like frame body 161a in which a large number of ventilation slits are formed. When the ozone-containing air passes through the filter material 161b, the filter material 161b removes ozone at a removal rate of 99% or more. As the filter material 161b, it is possible to use a material made of a conventionally known material.

  FIG. 13 is a perspective view showing devices related to the ozone exhaust system in the image forming unit together with the reverse exhaust fan 81. The first filter 161, the second filter 162, the third filter 163, and the fourth filter 164 are all exhausted to the outside of the casing above the sheet inversion device (28) (not shown) inside the casing. The ozone is removed through the air.

  FIG. 14 is a perspective view showing devices related to the paper discharge back surface ozone removal fan and the heat radiation development ozone removal fan in the housing. In the figure, a paper discharge unit inclusion duct 82 is a duct for guiding the air around the paper discharge roller to the paper discharge unit exhaust fan 172 in a state of containing a paper discharge roller (30 in FIG. 1) not shown. The discharge unit exhaust fan 172 connected to the rear end of the discharge unit inclusion duct 82 is driven to rotate, so that air existing around the discharge roller is moved from the front side of the copying machine to the rear side along the roller axis direction. It moves toward the side and is sucked into the paper discharge unit exhaust fan 172. A second filter 162 is fixed on the exhaust side of the paper discharge unit exhaust fan 172, and the air discharged from the paper discharge unit exhaust fan 172 passes through the second filter 162 and ozone is removed. It passes through the second louver (152 in FIG. 9) and is discharged out of the machine.

  Since the paper discharge unit exists near the charging device of the Y process cartridge (40Y), the air in the paper discharge unit may contain a small amount of ozone. For this reason, the air in the paper discharge unit is discharged to the outside through the second filter 162.

  The second filter 162 is fixed to the paper discharge unit exhaust fan 172, and is also fixed to a back surface exhaust fan (173 in FIG. 15) disposed on the side (side) of the paper discharge unit exhaust fan 172. ing. The back surface exhaust fan is for exhausting air existing on the back side of the housing to the outside of the machine. After the air sucked by the rear exhaust fan is exhausted from the rear exhaust fan, it passes through the second filter 162 to remove ozone, and then passes through the second louver (152 in FIG. 9). Discharged outside.

  Some of the air present in the region on the back side of the housing contains ozone emitted from the charging device of the process cartridge. For this reason, about the air which exists in the area | region of a back side, after passing ozone through the 2nd filter 162, it discharges | emits outside.

  In the present copier, the combination of the discharge unit exhaust fan 172, the back unit exhaust fan 173, and the second filter 162 fixed to these fans constitutes a “discharge back system ozone removal fan”.

  The heat sink 65 described above is disposed directly above the discharge section inclusion duct 82. The heat sink 65 is blown with an air flow for promoting heat radiation by the rotational driving of the fixing cooling fan 62 disposed in front of the heat sink 65. The airflow moves from the front side to the rear side in the longitudinal direction of the heat sink 65 while contacting the heat sink 65 and taking heat from the heat sink 65. The airflow that has moved to the rear end of the heat sink 65 is taken into the heat sink exhaust duct 66. A heat sink exhaust fan 171 is connected to the rear end of the heat sink exhaust duct 66. The heat sink exhaust fan 171 sucks the airflow entering the heat sink duct 66 and discharges it toward the rear side of the housing. The discharged air passes through the first filter (see FIG. 14), and after ozone is removed, it is discharged out of the machine via the first louver (151 in FIG. 9) provided in the housing. .

  Since the heat sink 65 exists in the vicinity of the process cartridge (40Y) for Y, the air around the heat sink 65 may contain a small amount of ozone. For this reason, the air existing around the heat sink 65 passes through the first filter 161 to remove ozone, and then is discharged outside the apparatus.

  FIG. 16 is a perspective view showing devices related to the development exhaust fan in the housing. The apparatus related to the development exhaust fan includes process cartridges for each color, but only the C process cartridge 40C is shown in FIG. A first developing duct 176 is disposed behind the C process cartridge 40C and a K process cartridge (not shown). A first developing exhaust fan 178 is connected to the first developing duct 176. Air exhausted from an exhaust port (not shown) provided in the C developing device 43C or an exhaust port provided in the K developing device (not shown) passes through an inlet (not shown) provided in the first developing duct 176. Received in the first developer duct 176. The first developing exhaust fan 178 sucks the airflow entering the first developing duct 176 and discharges it toward the rear side of the housing.

  A second developing duct 177 is disposed behind the M process cartridge and the Y process cartridge (not shown). A second development exhaust fan 179 is connected to the second development duct 177. Air exhausted from an exhaust port (not shown) provided in the M developing device (not shown) or an exhaust port provided in the Y developing device is passed through a receiving port (not shown) provided in the second developing duct 177. 2 is received in the development duct 177. The second developing exhaust fan 179 sucks the airflow entering the second developing duct 177 and discharges it toward the rear side of the housing.

  The first development exhaust fan 178, the second development exhaust fan 179, and the heat sink exhaust fan (171 in FIG. 15) are arranged in a side-by-side layout. The first filter 161 shown in FIG. 14 is fixed to these three exhaust fans. The air exhausted from the first developing exhaust fan 178 passes through the first filter 161 to remove ozone, and then is exhausted to the outside through the first louver (151 in FIG. 9) provided in the housing. . Further, the air discharged from the second developing exhaust fan 179 also passes through the first filter 161 to remove ozone, and is then discharged outside the apparatus through the first louver provided in the housing.

  Since each color developing device is disposed in the vicinity of each color charging device which is an ozone generation source, the air discharged from the exhaust port of the developing device may contain a small amount of ozone. . For this reason, the air discharged from the exhaust port of each color developing device is passed through the first filter 161 to remove ozone, and then discharged outside the apparatus.

  In this copying machine, the combination of the first developing exhaust fan 178, the second developing exhaust fan 179, the heat sink exhaust fan (171 in FIG. 14), and the first filter 161 fixed to these fans is “heat radiation developing ozone removal”. "Fan". Note that a temperature sensor 215 for detecting the temperature inside the apparatus is fixed to the second developing duct 177. The temperature sensor 215 is located behind a Y process cartridge (not shown). Since the Y process cartridge (40Y) exists right above the fixing device (25), it is likely to be the highest temperature among the process cartridges of each color.

  FIG. 17 is a perspective view showing devices related to the main ozone exhaust fan 175 in the housing. The devices related to the main ozone exhaust fan 175 include process cartridges for each color, but only the C process cartridge 40C is shown in FIG. Ozone exhaust ducts 174 are disposed behind the process cartridges for each color. A main ozone exhaust fan 175 is connected to the ozone exhaust duct 174. The charging inner portion 49C in the C process cartridge 40C is provided with a discharge port for discharging air around the charging device included in the charging inner portion 49C from the cartridge. Similar discharge ports are provided in the charging inner portions of the process cartridges of other colors. The ozone discharge duct 174 is provided with receiving ports 174K, 174C, 174M, and 174Y for receiving the airflow discharged from the discharge ports. Airflows discharged from the discharge outlets of the charging inner portions of the process cartridges of the respective colors are received in the ozone discharge duct 174 through the receiving ports 174K, 174C, 174M, and 174Y. The main ozone exhaust fan 175 discharges the airflow entering the ozone exhaust duct 174 toward the rear side of the housing while sucking the airflow.

  A third filter 163 is fixed to the ozone exhaust fan 175. The air exhausted from the ozone exhaust fan 175 passes through the third filter 163, and after the ozone is removed, it is exhausted to the outside through the third louver (153 in FIG. 9) provided in the housing. A large amount of ozone is contained in the air discharged from the charging enclosing part including the charging device which is an ozone generation source. For this reason, about the air discharged | emitted from the charging inclusion part, after removing ozone by the 3rd filter 163, it discharges | emits outside the apparatus.

  In this copying machine, the combination of the main ozone exhaust fan 175 and the third filter 163 constitutes a “main ozone removing fan”.

  FIG. 18 is a perspective view showing devices related to the belt and the fixing exhaust system in the housing. In the drawing, a fixing exhaust duct 180 is connected to the rear of the fixing device 25, and a fixing exhaust fan 181 is connected to an end of the fixing exhaust duct 180 on the outlet side. When the fixing exhaust fan 181 is driven to rotate, the air in the fixing exhaust duct 180 is sucked by the fixing exhaust fan 181, thereby generating a suction force at the suction port of the fixing exhaust duct 180. With this suction force, air existing behind the fixing device 25 is sucked into the fixing exhaust duct 180. Then, the air existing around the fixing device 25 moves from the front side to the rear side of the copying machine along the longitudinal direction of the fixing device 25 and is sequentially sucked into the fixing exhaust duct 180.

  A fourth filter 164 is fixed to the fixing exhaust fan 181 and a belt exhaust fan 182 described later. The air exhausted from the fixing exhaust fan 181 passes through the fourth filter 164, and after the ozone is removed, is exhausted to the outside through a fourth louver (154 in FIG. 9) provided in a housing (not shown). . The fixing device 25 exists at a position relatively distant from the process cartridges of the respective colors, but the fixing exhaust fan 181 exists near the process cartridge for Y. When the fixing exhaust fan 181 is driven to rotate and air is discharged from the fixing exhaust fan 181, the exhaust airflow may slightly entrain air existing around the fixing exhaust fan 181. The air existing around the fixing exhaust fan 181 may contain a small amount of ozone. For this reason, the air exhausted from the fixing exhaust fan 181 passes through the fourth filter 164 to remove ozone, and then is discharged outside the apparatus.

  Connected to the front end of the belt cleaning device 17 is an air supply fan 67 for sending air toward a cooling vent pipe (not shown) provided in the belt cleaning device 17. The air sent to the cooling vent pipe in the belt cleaning device 17 moves from the front side to the rear side of the copying machine and then passes through an exhaust port (not shown) provided on the rear wall of the case in the belt cleaning device 17. It is discharged from the belt cleaning device 17.

  A belt exhaust duct 169 is disposed behind the belt cleaning device 17, and a belt exhaust fan 182 is connected to the belt exhaust duct 169. When the belt exhaust fan 182 is driven to rotate, the air in the belt exhaust duct 196 is sucked into the belt exhaust fan 182. Then, a suction force is generated at the suction port of the belt exhaust duct 196. The airflow discharged from the exhaust port provided on the case rear wall of the belt cleaning device 17 is taken into the belt exhaust duct 196 by the above-described suction force and sucked into the belt exhaust fan 182.

  The air exhausted from the belt exhaust fan 182 passes through the fourth filter 164, and after the ozone is removed, is exhausted to the outside through a fourth louver (154 in FIG. 9) provided in a housing (not shown). . The belt cleaning device 17 exists at a position relatively distant from the process cartridges of the respective colors, but the belt exhaust fan 182 exists near the process cartridge for Y. When the belt exhaust fan 182 is rotationally driven and air is exhausted from the belt exhaust fan 182, the exhaust airflow may slightly entrain air existing around the belt exhaust fan 182. A small amount of ozone may be contained in the air around the belt exhaust fan 182. For this reason, the air discharged from the belt exhaust fan 182 passes through the fourth filter 164 to remove ozone, and then is discharged outside the apparatus.

  In this copying machine, the combination of the fixing exhaust fan 181, the belt exhaust fan 182, and the fourth filter 164 constitutes a “belt and fixing system ozone removing fan”.

Next, a characteristic configuration of the copier according to the embodiment will be described.
FIG. 19 is a block diagram illustrating a part of an electric circuit in the image forming unit of the copier according to the embodiment. In the figure, a control unit 200 controls driving and sensing of various devices in the image forming unit, and includes a CPU, a ROM, a RAM, and the like. The control unit 200 is connected to three exhaust fans (171, 178, 179) included in the heat radiation developing system ozone removal fan 191 and a main ozone exhaust fan 175 included in the main ozone removal fan 193. Also, two exhaust fans (181, 182) of the belt and fixing system ozone removal fan 194, two exhaust fans (172, 173) of the paper discharge rear system ozone removal fan, fixing cooling fan 62, air supply fan 67, temperature A sensor 215 and the like are also connected.

  The temperature sensor 215 detects the in-machine temperature behind the Y process cartridge (see FIG. 16). In addition, the fixing cooling fan 62 promotes heat radiation from the heat sink by sending air toward the heat sink (65) (see FIG. 8). The air supply fan 67 sends air into the belt cleaning device (17) to promote cooling of the belt cleaning device (see FIG. 18).

  FIG. 20 is a flowchart showing a processing flow of the fan drive control process performed by the control unit (200) as the fan control means. In this fan drive control process, the control unit first determines whether or not the energy saving mode is being executed (step 1: hereinafter, step is denoted as S). If the energy saving mode is being executed (Y in S1), after setting condition 1 as the fan drive control condition (S2), the process flow is looped to S10 described later. On the other hand, when the energy saving mode is not being executed (N in S1), the control flow proceeds to S3. The energy saving mode is a mode for waiting for an image formation start command from the user in a state where the heater power of the fixing device (25) is turned off. The heater power supply of the fixing device is usually turned on and heated even during standby in order to speed up the time from the start of the image formation start command from the user to the start of the image formation operation. However, if the image formation start command is not issued after a certain time, the heater power is turned off by executing the energy saving mode in order to prioritize energy saving over speeding up the time until the image forming operation starts. To do.

  In step S3, it is determined whether or not normal standby is being performed. The normal standby is a mode in which an image formation start command from the user is waited with the heater power of the fixing device turned on. When in normal standby (Y in S3), the control unit sets condition 2 as the fan drive control condition (S4), and then loops the processing flow to S10 described later. On the other hand, if not in normal standby (N in S3), the control flow proceeds to S5. If it is determined in step S3 that the apparatus is not normally waiting, an image forming operation is performed. That is, the visible image forming means including the process cartridges for each color is operating.

  In step S5, it is determined whether or not the detection result of the in-machine temperature sent from the temperature sensor (215) is less than 35 ° C. When the in-machine temperature is lower than 35 ° C. (Y in S5), the control unit sets condition 3 as the fan drive control condition (S6), and then loops the processing flow to S10 described later. On the other hand, if it is not less than 35 ° C. (N in S5), the process flow proceeds to S7.

  In step S7, it is determined whether or not the detection result of the in-machine temperature sent from the temperature sensor is in the range of 35 ° C. or higher and lower than 45 ° C. When the in-machine temperature is in the above-described range (Y in S7), the control unit sets condition 4 as the fan drive control condition (S8), and then loops the processing flow to S10 described later. On the other hand, if it is not within the above range (N in S7), after setting condition 5 as the fan drive control condition (S9), the process flow proceeds to S10.

In step S10, the control unit specifies details of the drive control conditions for each fan from the data table shown in Table 1 below. Then, each fan is rotationally driven under the specified drive control condition (S11).

  As shown in Table 1, when the condition 1 corresponding to the energy saving mode and the condition 2 corresponding to the normal standby are set as the fan drive control conditions, the image forming operation is stopped. For this reason, ozone is not generated from the charging device of each color process unit. Further, in the energy saving mode, in addition to the image forming operation being stopped, since the heater power of the fixing device is turned off, the temperature inside the apparatus is not increased. On the other hand, in normal standby, since the heater power of the fixing device is on, the in-machine temperature rises unless the fan is driven. Therefore, when the condition 1 corresponding to the energy saving mode is set, the rotational drive of all the fans is stopped. On the other hand, when the condition 2 corresponding to the normal standby is set, only the fixing exhaust fan 181 and the belt exhaust fan 182 of the belt and the fixing system ozone removing fan 194 are driven to rotate at low speed. Then, the rotational drive of other fans is stopped. As a result, the heat generated from the fixing device is discharged outside the apparatus to prevent the temperature inside the apparatus from rising.

  When Condition 3 or Condition 4 is set as the fan drive control condition, ozone is generated from the charging device of the process cartridge because the image forming operation is performed. In addition to the fact that the heater power of the fixing device is turned on, various drive system devices are driven to generate heat, so that the amount of heat generated in the apparatus is larger than that during standby. If each fan is driven to rotate at a high speed, even if a large amount of heat is generated in the machine, the heat can be efficiently discharged outside the machine to keep the temperature inside the machine below a certain temperature. However, if each fan is driven to rotate at a high speed even though the in-machine temperature has not increased so much, useless energy consumption and useless noise are generated.

  Therefore, when the condition 3 corresponding to the in-machine temperature of 35 ° C. or less is set, the heat sink exhaust fan 171, the first developer exhaust fan 178, and the second developer exhaust provided in the heat radiation development system ozone removal fan 191 are set. Each fan 179 is rotated at a low speed. Further, the sheet discharge unit exhaust fan 172 and the back unit exhaust fan 173 provided in the sheet discharge back system ozone removal fan 192 are rotated at low speeds. Further, the fixing exhaust fan 181 and the belt exhaust fan 182 included in the belt and fixing system ozone removing fan 194 are rotated at low speeds. Further, the main ozone exhaust fan 175 of the main ozone removal fan 193 is rotated at a high speed. Of the four ozone removal fans, the main ozone removal fan 193 rotates the exhaust fan at high speed because the ozone generated from the charging device of the process cartridge is surely sucked into the main ozone removal fan 193 and diffused in the machine. This is to prevent the occurrence of the above. For the three ozone removal fans (191, 192, 194), by reducing the rotational drive speed of the exhaust fan, it is possible to save energy and reduce the increase in internal temperature due to exhaust, compared to the case of increasing the speed. Low noise can be achieved. At this time, the rotation of the reverse exhaust fan 81 not provided with a filter is stopped. As a result, it is possible to prevent ozone from leaking out of the apparatus due to exhaust by the reverse exhaust fan 81.

  On the other hand, when the condition 4 corresponding to the in-machine temperature of 35 ° C. or higher and lower than 45 ° C. is set as the fan drive control condition, it is necessary to increase the exhaust amount by driving each fan and lower the in-machine temperature. There is. Therefore, when the condition 4 is set, all the exhaust fans in the four ozone removal fans (191 to 194) are rotationally driven at a high speed. Further, the reverse exhaust fan 81 not provided with the filer is also driven to rotate at a high speed to promote a decrease in the in-machine temperature. Since all the exhaust fans in the four ozone removal fans are rotated at a high speed, the ozone hardly wraps around the sheet reversing device (28) at a position away from the process cartridge. For this reason, even if the reverse exhaust fan 81 not provided with a filter is rotated at high speed, the exhaust by the reverse exhaust fan 81 hardly leaks ozone outside the apparatus.

  In this copying machine, when all exhaust fans of the four ozone removal fans (191 to 194) are rotationally driven at a high speed, the total exhaust amount per unit time of the ozone removal fans is expressed as follows. The performance of each fan is selected so that That is, the above-mentioned total is made larger than the total per unit time when the three reversing exhaust fans 81 are rotationally driven at high speed. For this reason, in the apparatus, an air flow is directed from the sheet reversing device (28) side, which is the air suction target of the reverse exhaust fan 81, toward the intermediate transfer belt 11 side or process cartridge side, which is the air suction target of each ozone removal fan. Occur. Therefore, when each fan is rotationally driven under the fan drive control condition of condition 4, the ozone leakage from the reverse exhaust fan 81 can be almost eliminated.

  When the in-machine temperature is 45 ° C or higher, the heat generated in the machine is higher than the decrease in the in-machine temperature by rotating each fan at high speed and exhausting from the inside of the machine. It will be raised. Therefore, when the condition 5 corresponding to the in-machine temperature of 45 ° C. or higher is set, the control unit temporarily stops the image forming operation while maintaining the high-speed rotation driving of each fan. At this time, the heater power of the fixing device is also turned off. In this state, the apparatus waits for the in-machine temperature to fall below 35 ° C., and when it falls, the image forming operation is resumed.

  As described above, in the present copier, the air existing in the vicinity of the charging device (42) as the ozone generation source in the housing (1a) is filtered by the ozone removing fan (191 to 194). ) To discharge outside the housing. Thereby, discharge | emission of ozone outside a housing can be suppressed. Further, the filter is omitted for the reversing exhaust fan 81 for exhausting the air around the sheet reversing device which is highly likely not to contain ozone because it is located relatively far from the charging device in the housing. A non-ozone removal fan. Thereby, cost reduction can be achieved. Further, when the temperature of the air in the enclosure is less than 35 ° C. as the first threshold (when the need for exhaust is low), compared to when the need for exhaust is high (when it is 35 ° C. or higher) The drive speed during operation of the ozone removing fan (191 to 194) and the reverse exhaust fan 81 is decreased. Thereby, energy saving and noise reduction are achieved while preventing generation of ozone exhaust by the reversing exhaust fan 81 due to slowing of the operating driving speed (rotational driving speed during the image forming operation) of only the ozone removing fan. be able to.

What has been described above is merely an example, and the present invention has a specific effect for each of the following modes.
[Aspect A]
Aspect A includes a visible image forming unit (for example, a process cartridge) that forms a visible image (for example, a toner image) on a recording member (for example, a recording sheet), and a housing (including a visible image forming unit). For example, a housing 1a) and an exhaust fan for exhausting air existing in the vicinity of an ozone generation source of the visible image forming means to outside the housing while passing through a filter (for example, filters 161 to 164) having an ozone removing capability. A non-exhaust fan for exhausting air present at a relatively distant position from the ozone generation source in the enclosure to the outside of the enclosure without passing through the filter; In an image forming apparatus (for example, a copying machine) provided with an ozone removing fan (for example, a reverse exhaust fan 81), a temperature detection for detecting the temperature inside the housing. Means (for example, a temperature sensor 215) and an operating driving speed which is a rotational driving speed of the ozone removing fan or the non-ozone removing fan during the operation of the visible image forming means, and the temperature detecting means When the detection result is equal to or less than a predetermined first threshold value or less than a first threshold value (for example, less than 35 ° C.), the detection result exceeds the first threshold value or greater than or equal to the threshold value (for example, 35 ° C. or more). Fan control means (for example, the control part 200) which performs the process which respectively slows the driving speed at the time of the operation | movement of the ozone removal fan or the said non-ozone removal fan is provided.

[Aspect B]
Aspect B is the operation driving speed of the ozone removal fan and the driving speed of the non-ozone removal fan when the detection result is equal to or lower than the first threshold value or less than the first threshold value in the aspect A, respectively. The exhaust amount per unit time by the non-ozone removal fan is set to a value that is less than the exhaust amount per unit time by the rotational drive of the ozone removal fan. In this configuration, as described above, non-ozone removal is achieved by generating an air flow from the air suction target position side of the non-ozone removal fan toward the air suction target position side of the ozone removal fan in the housing. Leakage of ozone from the fan can be almost eliminated.

[Aspect C]
In aspect C, in the aspect B, during the operation of the visible image forming unit, when the detection result is equal to or less than the first threshold value or less than the first threshold value, the rotation driving of the non-ozone removing fan is stopped. The fan control means is configured so as to perform the processing to be performed. In such a configuration, when the in-machine temperature is equal to or lower than the first threshold value or lower than the first threshold value, it is possible to prevent ozone leakage from the non-ozone removing fan by stopping the rotational driving of the non-ozone removing fan. .

[Aspect D]
Aspect D is any one of Aspects A to C, and when the detection result exceeds a second threshold that is greater than the first threshold or is equal to or higher than the second threshold (for example, 45 ° C. or higher). The fan control unit is configured to perform processing for temporarily stopping the operation of the image forming unit. In such a configuration, when the increase in the internal temperature due to the driving of each device is larger than the decrease in the internal temperature due to the driving of each fan, the drive of each device is temporarily stopped to avoid further increase in the internal temperature. The in-machine temperature can be lowered to a desired level. Thereby, generation | occurrence | production of the excessive raise of in-machine temperature can be avoided.

[Aspect E]
Aspect E is any one of Aspects A to D, as the visible image forming means, a latent image carrier (for example, photoconductor 41) that carries a latent image, and charging that uniformly charges the surface of the latent image carrier. Means (for example, charging device 42), latent image writing means (for example, optical writing units 20a and 20b) for writing a latent image on the surface after uniform charging, and developing means (for developing the latent image to obtain a toner image) For example, the developing device 43), transfer means for transferring the toner image on the latent image carrier to a recording member (for example, the transfer device 10), and fixing means for fixing the toner image on the surface of the recording member (for example, the fixing device 25). ), And as the ozone removing fan, a first ozone removing fan (for example, a main ozone removing fan 193) for exhausting air existing in the vicinity of the charging unit, and the developing unit or the fixing unit A second ozone removing fan (for example, a heat radiation developing system ozone removing fan 191, a belt and a fixing system ozone removing fan 194) for exhausting air existing in the vicinity of the stage is provided, and the visible image forming means is being driven While controlling the operation driving speed of the second ozone removal fan according to the detection result, the detection result of the first ozone removal fan is the first threshold regardless of the detection result. The fan control means is configured to perform a process of rotationally driving at an operation driving speed that is faster than the operation driving speed of the second ozone removal fan in the case where it is less than or less than the first threshold. It is a feature. In such a configuration, when the in-machine temperature is equal to or lower than the first threshold value or less than the first threshold value, ozone generated from the charging means that is an ozone generation source is intensively filtered by the first ozone removing fan. , It is possible to suppress the diffusion of ozone in the aircraft.

10: Transfer device (transfer means that is part of the visible image forming means)
20a, 20b: Optical writing unit (latent image writing means which is part of visible image forming means)
25: Fixing device (fixing means)
40: Process cartridge (part of visible image forming means)
41: Photoconductor (latent image carrier)
42: Charging device 43: Developing device (developing means)
161: First filter 162: Second filter 163: Third filter 164: Fourth filter 181: Inverted exhaust fan (non-ozone removing fan)
191: Heat radiation development system ozone removal fan (second ozone removal fan)
192: Ozone removal fan for paper discharge rear system 193: Main ozone removal fan (first ozone removal fan)
194: Belt and fixing system ozone removal fan (second ozone removal fan)
200: Control unit (fan control means)
215: Temperature sensor (temperature detection means)

JP 2006-220794 A

Claims (5)

Visible image forming means for forming a visible image on the recording member, a housing containing the visible image forming means, and air present in the vicinity of an ozone generation source of the visible image forming means having an ozone removing ability An ozone removal fan, which is an exhaust fan for exhausting outside the housing while passing through a filter, and outside the housing without passing air present at a position relatively distant from the ozone generation source inside the housing through the filter In an image forming apparatus provided with a non-ozone removal fan that is an exhaust fan for discharging,
Temperature detecting means for detecting the temperature in the enclosure;
The operating speed that is the rotational driving speed of the ozone removing fan or the non-ozone removing fan during the operation of the visible image forming means is controlled, and the detection result by the temperature detecting means is not more than a predetermined first threshold value. Alternatively, when it is less than the first threshold value, the operation speed of the operation of the ozone removal fan or the non-ozone removal fan is decreased as compared with the case where the first threshold value is exceeded or the threshold value is greater than or equal to the threshold value. An image forming apparatus comprising: a fan control unit for carrying out. The image forming apparatus according to claim 1.
When the detection result is equal to or lower than the first threshold value or less than the first threshold value, the driving speed of the ozone removing fan and the driving speed of the non-ozone removing fan are rotated. The image forming apparatus is characterized in that the exhaust amount per unit time by the non-ozone removing fan is set to be smaller than the exhaust amount per unit time by. The image forming apparatus according to claim 2.
During the operation of the visible image forming unit, when the detection result is equal to or less than the first threshold value or less than the first threshold value, a process of stopping the rotational driving of the non-ozone removing fan is performed. An image forming apparatus comprising the fan control means. The image forming apparatus according to any one of claims 1 to 3,
When the detection result exceeds a second threshold value greater than the first threshold value or is equal to or greater than the second threshold value, the fan control is performed so as to perform a process of temporarily stopping the operation of the visible image forming unit. An image forming apparatus comprising a means. The image forming apparatus according to any one of claims 1 to 4,
As the visible image forming means, a latent image carrier for carrying a latent image, a charging means for uniformly charging the surface of the latent image carrier, and a latent image writing means for writing a latent image on the surface after uniform charging Developing means for developing the latent image to obtain a toner image, transfer means for transferring the toner image on the latent image carrier to a recording member, and fixing means for fixing the toner image on the surface of the recording member. Use things
As the ozone removing fan, a first ozone removing fan for exhausting air existing in the vicinity of the charging means, and a second ozone removing fan for exhausting air present in the vicinity of the developing means or the fixing means. With fans,
While the visible image forming unit is being driven, the operation driving speed of the second ozone removal fan is controlled according to the detection result, while the first ozone removal fan is controlled regardless of the detection result. , So as to perform a process of rotationally driving at a driving speed that is faster than the driving speed of the second ozone removal fan when the detection result is less than or equal to the first threshold value or less than the first threshold value. An image forming apparatus comprising the fan control means.

Images