JP5803575B2 - Image forming apparatus - Google Patents

Description

  The present invention relates to an image forming apparatus such as a multifunction peripheral, and more particularly to an electrophotographic image forming apparatus that transfers a toner image onto a recording sheet and fixes the image by heat.

  Conventionally, in an electrophotographic image forming apparatus, when a toner image transferred onto a recording sheet is fixed on the recording sheet with heat by a fixing device, the recording sheet is heated at a high temperature. Evaporate. When this water vapor moves upward and condensation occurs on each member of the image forming apparatus, each member may corrode. In particular, when condensation occurs on an electronic member, there is a risk that failures such as electrode corrosion and electrical circuit short-circuiting may occur. Further, when condensed water droplets fall on the recording paper and the fixing device, problems such as deformation of the recording paper, poor fixing, or adhesion of water droplets to a user who has taken out the recording paper to which the water droplets are attached occur.

  Therefore, a technique for dealing with the above problem is disclosed (for example, see Patent Document 1).

  In the technique described in Patent Document 1, a ventilation path is provided above the fixing device, and water vapor can be discharged out of the image forming apparatus by natural retention, and a lattice-like rib is provided in the ventilation path to condense water vapor. It can be attached by surface tension and dried naturally.

JP-A-9-90855

  However, the image forming apparatus described in Patent Document 1 requires a ventilation path in the apparatus in order to remove water vapor. That is, the problem that the apparatus itself becomes large arises. Further, since the image forming apparatus described in Patent Document 1 cannot suppress the amount of water vapor discharged outside the image forming apparatus, a large amount of water vapor may be discharged outside the image forming apparatus. . Therefore, when a large amount of water vapor enters the reading mechanism installed at the upper part of the apparatus, a reading failure occurs, or in a predetermined environment, the water vapor looks like smoke, so that the user may mistakenly think that it is a failure. Problems arise.

  Therefore, the present invention has been made in view of such a situation, and it is possible to remove water vapor without increasing the size of the device itself, and to suppress the amount of water vapor discharged outside the device. An object is to provide an image forming apparatus.

  In order to achieve the above object, an image forming apparatus according to an aspect of the present invention is an image forming apparatus that forms an image on recording paper, and fixes the toner image transferred onto the conveyed recording paper by heat. A fixing device, an exterior cover having an exhaust port for discharging water vapor generated from the recording paper by being fixed by the fixing device to the outside of the image forming apparatus, and a porous material that absorbs part of the water vapor. A water adsorbing member, and the water adsorbing member is fixed above the fixing device and below the exterior cover, and the water vapor rises along a part of the conveyance path of the recording paper The water vapor is fixed at a position where it passes through the moisture adsorbing member.

  According to this configuration, the water adsorbing member is fixed at a position where the water vapor passes through the water adsorbing member after the water vapor rises along a part of the recording paper conveyance path. That is, since a dedicated ventilation path for removing water vapor is not provided in the apparatus, it is possible to remove water vapor without enlarging the apparatus itself.

  Moreover, since a part of water vapor | steam is absorbed by the porous water | moisture-content adsorption | suction member, the quantity of the water vapor | steam discharged | emitted out of an apparatus is suppressed below to a fixed amount.

  Preferably, the image forming apparatus further includes a fixing member and a sheet passing guide provided along the conveyance path, the outer cover is fixed in the image forming apparatus, and the moisture adsorbing member is fixed to the outer cover. It is fixed in a state of being sandwiched between members.

  According to this configuration, the moisture adsorbing member is securely fixed by being sandwiched between the exterior cover and the sheet passing guide, which is a mechanism originally provided in the image forming apparatus.

  Preferably, a fixing member having a protrusion for aligning the moisture adsorbing member is attached to the exterior cover.

  According to this configuration, the moisture adsorption member can be installed at a desired position.

  The fixing member and the paper passing guide are detachably attached to the exterior cover, and the moisture adsorbing member is replaceable.

  According to this configuration, the moisture adsorbing member can be easily replaced, and the amount of water vapor discharged outside the apparatus can be adjusted.

  According to the present invention, it is possible to provide an image forming apparatus capable of removing water vapor without increasing the size of the apparatus itself and adjusting and suppressing the amount of water vapor discharged outside the apparatus.

1 is an external perspective view of a multifunction peripheral according to an embodiment of the present invention. FIG. 2 is a front sectional view showing the inside of the main body of the multifunction peripheral according to the embodiment of the present invention. 1 is a cross-sectional view of a main part showing a main part of a multifunction peripheral according to an embodiment of the present invention. FIG. 3 is an external perspective view when the jam access cover of the multifunction peripheral according to the embodiment of the present invention is opened. It is a disassembled perspective view of the water | moisture-content adsorption | suction part of the multifunctional machine which concerns on embodiment of this invention. It is a side view of the water | moisture-content adsorption | suction part (closed state) of the multifunctional device which concerns on embodiment of this invention. It is a side view of the water | moisture-content adsorption | suction part (open state) of the multifunctional device which concerns on embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Each figure is a schematic diagram and is not necessarily illustrated exactly. Each of the embodiments described below shows a preferred specific example of the present invention. The numerical values, shapes, materials, constituent elements, arrangement positions and connecting forms of the constituent elements shown in the following embodiments are merely examples, and are not intended to limit the present invention. The present invention is limited only by the claims. Therefore, among the constituent elements in the following embodiments, constituent elements that are not described in the independent claims indicating the highest concept of the present invention are not necessarily required to achieve the object of the present invention. It will be described as constituting a preferred form.

  In the embodiment of the present invention, a case where the image forming apparatus is a multifunction peripheral will be described.

  FIG. 1 is an external perspective view of a multifunction peripheral according to an embodiment of the present invention.

  An MFP 501 according to an embodiment of the present invention includes an image reading unit 511 functioning as a scanner, an operation panel 512 for instructing the number of copies, a facsimile transmission destination, and the like, and a recording sheet 100 as a recording medium. A main body 513 including an image forming unit to be formed, a paper feed cassette 514 for sequentially supplying the recording paper 100, and a paper discharge tray 515 for discharging the recording paper 100 on which an image is formed are provided.

  The multi-function device 501 according to the embodiment of the present invention includes a front cover 521 on the front side of the main body 513 (the side on which the operation panel 512 is provided) and a jam access cover 522 on one side surface. . The front cover 521 and the jam access cover 522 can be opened and closed. For example, when maintenance work or the like is performed, the inside of the main body 513 can be accessed by opening the front cover 521 and the jam access cover 522.

  FIG. 2 is a front sectional view showing the inside of the main body of the multifunction peripheral according to the embodiment of the present invention.

  The multi-function device 501 according to this embodiment includes a paper feed cassette 514 that supplies the recording paper 100 at the lower portion of the main body 513. The paper feed cassette 514 can be pulled out to the front side of the apparatus (the front side in FIG. 2). An image forming unit 11 is provided above the paper feed cassette 514, and a fixing device 91 and a paper discharge tray 515 are further provided thereon.

  Inside the main body 513, a transport path 531 (corresponding to the transport path of the recording paper of the present invention) for transporting the recording paper 100 from the paper feed cassette 514 to the paper discharge tray 515 is formed. The conveyance path 531 extends upward from one end side of the paper feed cassette 514 to reach the image forming unit 11, further extends upward, passes through the fixing device 91, and then bends in the horizontal direction to be the paper discharge tray 515. It is configured to reach the top. Although not shown in FIG. 2, an image reading unit 511 and an operation panel 512 are disposed above the paper discharge tray 515.

  The paper feed cassette 514 is formed to be open upward, and a plate-shaped flapper 532 is provided at the bottom. A plurality of recording papers 100 are stacked on the flapper 532. An urging spring (not shown) for pushing the flapper 532 upward is attached to the flapper 532. Further, the paper feed roller 21 is disposed above the flapper 532. With the above configuration, when the paper feed roller 21 is driven in a state where the flapper 532 is biased upward, the uppermost recording paper 100 in the paper feed cassette 514 is separated and taken out, and is fed to the transport path 531. The recording paper 100 is sent out.

  In the conveyance path 531, the separation roller 22 is disposed immediately downstream of the paper feed roller 21. The separation roller 22 is driven while the recording paper 100 is nipped between the separation roller 22 and the roller disposed so as to separate the recording paper 100 one by one. A registration roller 23 is disposed on the downstream side of the separation roller 22. The registration roller 23 is driven while the recording paper 100 is nipped between the registration roller 23 and the roller disposed opposite to the registration roller 23, thereby correcting the skew of the recording paper 100 and feeding the recording paper 100 to the downstream image forming unit 11. Transport.

  The image forming unit 11 forms an image on the recording paper 100, and as shown in FIG. 2, around the photosensitive drum 12, a charger 13, an LED head 14, a developing device 15, and a transfer roller. 16 and a cleaner 17 are arranged.

  The photosensitive drum 12 has a photoconductive film formed of an organic photoreceptor on the surface thereof, and is configured to be rotationally driven by an electric motor (not shown).

  The charger 13 is a non-contact corona charging type so-called scorotron charger, and the surface of the photosensitive drum 12 is uniformly charged, for example, negatively by the charger 13.

  The LED head 14 serving as an exposure unit is disposed downstream from the charger 13 (refers to the downstream side in the rotation direction of the photosensitive drum 12. Hereinafter, the same applies to the description of the developing device 15, the transfer roller 16, and the cleaner 17). In addition, a large number of light emitting diodes (LEDs) are arranged in the width direction of the recording paper 100. A lens array in which a large number of gradient index lenses are arranged is disposed on the surface of the LED head 14. The LED head 14 selectively emits light corresponding to image data of a facsimile document received via a communication line or image data read by the image reading unit 511. As a result, the surface of the photosensitive drum 12 is selectively exposed, and the electrostatic energy is formed by losing the charge energy of the exposed portion.

  The developing device 15 is disposed on the downstream side of the LED head 14. The developing device 15 is configured by a two-component developing method using toner and carrier as developers. Specifically, the developing device 15 includes a developer container 35 made of synthetic resin, two screw-shaped stirring members 31 and 32 disposed inside the developer container 35, and a slight gap with respect to the photosensitive drum 12. And a developer carrying member 33 supported by the developer container 35, and a regulation plate 34 arranged close to the surface of the developer carrying member 33.

  The stirring members 31 and 32 are driven to rotate, whereby the two-component developer is circulated in the developer container 35 while the toner and the carrier are evenly mixed.

  The developer carrier 33 is a non-magnetic material, is formed in a cylindrical shape, and is fitted to the outside of the columnar magnetic body 36.

  The internal magnetic body 36 attracts the two-component developer to the surface of the developer carrier 33 by the magnetism, and rotates the developer carrier 33 in this state, so that the two-component developer is the developer carrier 33. The photosensitive drum 12 is fed to the photosensitive drum 12 while being held on the surface. Note that the thickness of the two-component developer on the surface of the developer carrier 33 is regulated by the regulation plate 34 so as to be uniform.

  Thereafter, in the vicinity of the photosensitive drum 12 and the developer carrying member 33, only the portion of the two-component developer on the surface of the developer carrying member 33 where the toner corresponds to the exposed portion by the LED head 14 is included in the photosensitive drum 12. Move selectively to the surface. As a result, a toner image corresponding to the electrostatic latent image is formed on the surface of the photosensitive drum 12. Of the two-component developer, the remaining toner that has not moved to the carrier and the photosensitive drum 12 side is collected in the developer container 35.

  The transfer roller 16 is disposed on the downstream side of the developing device 15 and is disposed on the opposite side of the photosensitive drum 12 with the conveyance path 531 interposed therebetween. A predetermined voltage is applied to the transfer roller 16 from a power source. Therefore, the toner image formed on the surface of the photosensitive drum 12 moves toward the transfer roller 16 side by the rotation of the photosensitive drum 12, and is transferred onto the recording paper 100 by the electric field attraction force.

  The cleaner 17 is disposed on the downstream side of the transfer roller 16, and removes the residual toner that has not been transferred to the recording paper 100 at the transfer roller 16, and scrapes and stores it from the surface of the photosensitive drum 12. It is configured.

  Of the configuration of the image forming unit 11, at least the photosensitive drum 12, the charger 13, the developing unit 15, and the cleaner 17 are housed in a synthetic resin cartridge and configured as a process cartridge (process unit). In the image forming unit 11, the recording paper 100 onto which the toner image has been transferred is sent to the fixing device 91 on the downstream side of the conveyance path 531 by the rotation of the photosensitive drum 12.

  FIG. 3 is a cross-sectional view of the main part showing the main part of the multifunction peripheral according to the embodiment of the present invention.

  As shown in FIG. 3, the fixing device 91 fixes the toner image transferred onto the conveyed recording paper 100 by heat, and is opposed to the heat roll 92 that is rotationally driven and the heat roll 92. And a press roller 93 to be disposed. The fixing device 91 includes a housing 55 that houses the heat roll 92 and the press roller 93. The press roller 93 is pressed against the heat roll 92 by a biasing spring (not shown). With this configuration, when the recording paper 100 passes between the heat roll 92 and the press roller 93, the toner of the toner image is melted by the heat of the high-temperature heat roll 92 and the pressure by the press roller 93 to form the recording paper 100. To settle. At this time, the moisture contained in the recording paper 100 becomes the water vapor 70 by the heat of the heat roll 92. As shown in FIG. 3, the water vapor 70 rises along a part of the conveyance path 531. Thereafter, the water vapor 70 moves toward the moisture adsorbing member 220 in the moisture adsorbing portion 200 disposed above the fixing device 91. The water vapor 70 is partially absorbed by the moisture adsorbing member 220, and the water vapor 70 that has not been absorbed is discharged out of the multi-function device 501.

  Further, the fixing device 91 is provided with a separation claw 94 for preventing the recording paper 100 from being wrapped around the heat roll 92 while being stuck.

  Further, a conveyance roller 95 is provided on the downstream side of the fixing device 91, and a paper discharge roller 96 is provided on the further downstream side. With this configuration, the recording paper 100 conveyed from the fixing device 91 is nipped between the conveying roller 95 and a driven roller disposed opposite thereto, and is sent to the downstream side. Further, the recording paper 100 is nipped between the paper discharge roller 96 and a subordinate roller disposed opposite thereto, and is discharged onto the paper discharge tray 515.

  FIG. 4 is an external perspective view of the multifunction peripheral according to the embodiment of the present invention when the jam access cover is opened.

  For example, in the maintenance work and the work for exchanging the moisture adsorbing member 220 described later, the fixing device 91 and the moisture adsorbing unit 200 in the multifunction machine 501 can be accessed by opening the jam access cover 522. .

  FIG. 5 is an exploded perspective view of the moisture adsorbing unit of the multifunction machine according to the embodiment of the present invention.

  The moisture adsorption unit 200 includes an exterior cover 210, a moisture adsorption member 220, a fixing member 230, and a paper passing guide 240.

  The exterior cover 210 is a cover that constitutes a part of the housing of the multi-function device 501 and is made of plastic. Further, the exterior cover 210 has an exhaust port 215 that is a lattice-shaped slit provided for discharging the water vapor 70 generated from the fixing device 91.

  As shown in FIG. 3, the moisture adsorbing member 220 is fixed above the fixing device 91 and below the exterior cover 210, and after the water vapor 70 rises along a part of the conveyance path 531, It is fixed at a position passing through the moisture adsorbing member 220.

  The moisture adsorbing member 220 is for absorbing a part of the water vapor 70, and is a porous material such as a sponge. In the moisture adsorbing member 220, holes having a diameter of 1 mm are provided in a lattice shape on the surface and inside of the moisture adsorbing member 220.

  Depending on the dimensions of the moisture adsorbing member 220, the amount of water vapor discharged to the outside of the multi-function device 501 can be suppressed to a certain amount or less. The water vapor 70 that has not been absorbed by the moisture adsorbing member 220 is discharged out of the multi-function device 501 through the exhaust port 215.

  The fixing member 230 has a function of aligning the moisture adsorption member 220 and is made of plastic. The fixing member 230 is provided with plastic protrusions 250 at two corners as shown in FIG. 5 so as to match the dimensions of the moisture adsorbing member 220. By fitting the moisture adsorbing member 220 into the protrusion 250 provided on the fixing member 230, the moisture adsorbing member 220 can be fixed at a desired position.

  The sheet passing guide 240 is provided along the conveyance path 531 in FIG. 3 and is made of plastic. The recording paper 100 is conveyed in the direction of the paper discharge tray 515 along the lower surface of the paper passing guide 240. A paper passage guide 240 is provided so that the recording paper 100 is securely nipped between the paper discharge roller 96 and a subordinate roller disposed opposite thereto, and discharged onto the paper discharge tray 515.

  FIG. 6A is a side view of the moisture adsorbing portion (closed state) of the multifunction peripheral according to the embodiment of the present invention. FIG. 6B is a side view of the moisture adsorbing portion (open state) of the multifunction peripheral according to the embodiment of the present invention.

  The exterior cover 210 is fixed in the multifunction machine 501, and the fixing member 230 and the paper passing guide 240 are fixed to the exterior cover 210. The moisture adsorbing member 220 is sandwiched between the exterior cover 210 and the fixing member 230. The exterior cover 210, the fixing member 230, and the sheet passing guide 240 are installed in the vicinity of a driven roller disposed opposite to the paper discharge roller 96 in FIG. 3, and are connected by a rotation shaft 216 for opening and closing the exterior cover 210. Yes. A fixing member 230 having a function of fixing the moisture adsorbing member 220 is detachably attached to the exterior cover 210 with a screw. Accordingly, the fixing member 230 can be removed from the exterior cover 210 by removing the screw after opening the exterior cover 210 with the rotating shaft 216 as a fulcrum, so that the moisture adsorption member 220 can be easily replaced. .

  As described above, according to the multi-function device 501 according to the embodiment, the moisture adsorbing member 220 is fixed at a position where the water vapor 70 passes through the moisture adsorbing member 220 after the water vapor 70 rises a part of the transport path 531. Has been. That is, since a dedicated ventilation path for removing the water vapor 70 is not provided in the multi-function device 501, the water vapor 70 can be removed without enlarging the multi-function device 501 itself. In addition, since a part of the water vapor 70 is absorbed by the porous moisture adsorbing member 220, the amount of the water vapor 70 discharged to the outside of the multi-function device 501 can be suppressed to a certain amount or less.

  Although the image forming apparatus according to one aspect of the present invention has been described above, the present invention is not limited to these embodiments. Unless it deviates from the gist of the present invention, various modifications conceived by those skilled in the art are applied to the present embodiment, or forms constructed by combining components in different embodiments are also included in the scope of the present invention. .

  For example, the moisture adsorbing member 220 is not limited to a sponge, and may be a cloth, a nonwoven fabric, a ceramic, a single piece of wood, or a mixture thereof.

  The present invention can remove water vapor without enlarging the apparatus itself, for example, as an image forming apparatus such as a multifunction machine, and particularly as an electrophotographic image forming apparatus that transfers a toner image onto recording paper and fixes it by heat. And an image forming apparatus capable of suppressing the amount of water vapor discharged outside the apparatus.

DESCRIPTION OF SYMBOLS 11 Image formation part 12 Photosensitive drum 13 Charger 14 LED head 15 Developing device 16 Transfer roller 17 Cleaner 21 Paper feed roller 22 Separation roller 23 Registration roller 31, 32 Stirring member 33 Developer carrier 34 Restriction plate 35 Developer container 36 Magnetic Body 55 Housing 70 Water vapor 91 Fixing device 92 Heat roll 93 Press roller 94 Separating claw 95 Transport roller 96 Paper discharge roller 100 Recording paper 200 Moisture adsorption part 210 Exterior cover 215 Exhaust port 216 Rotating shaft 220 Moisture adsorption member 230 Fixing member 240 Paper passing Guide 250 Projection 501 Multifunction device 511 Image reading unit 512 Operation panel 513 Main body 514 Paper feed cassette 515 Paper discharge tray 521 Front cover 522 Jam access cover 531 Carriage path 532 Flapper

Claims (2)

An image forming apparatus for forming an image on recording paper,
A fixing device that fixes the toner image transferred onto the conveyed recording paper by heat;
An exterior cover having an exhaust port for discharging water vapor generated from the recording paper by being fixed by the fixing device to the outside of the image forming apparatus;
A porous moisture adsorbing member that absorbs part of the water vapor,
The moisture adsorbing member is fixed above the fixing device and below the exterior cover, and after the water vapor rises along a part of the conveyance path of the recording paper, the water vapor adsorbs the water adsorbing member. is fixed to the passing position,
The image forming apparatus further includes:
A fixing member and a paper passing guide provided along the transport path;
The exterior cover is fixed in the image forming apparatus,
The moisture adsorbing member is fixed in a state sandwiched between the exterior cover and the fixing member,
An image forming apparatus in which a fixing member having a protrusion for aligning the moisture adsorbing member is attached to the exterior cover . Wherein the outer cover, the fixing member and the paper feed guide detachably attached to the image forming apparatus according to claim 1 wherein the moisture adsorption member are interchangeable.

Images