JP5915852B2 - Image forming apparatus - Google Patents

Description

  The present invention relates to an image forming apparatus.

  In Patent Document 1, a transfer belt that transfers image information held on an image carrier onto transfer paper, electrostatically attracts the transfer paper and transports it toward a fixing unit, and drives the transfer belt. An image forming apparatus comprising: a driving unit that performs charging; a charging unit that applies charge to the transfer belt; and a transfer conveyance device that includes a guide member that guides the transfer sheet immediately after the transfer sheet is separated from the transfer belt. The width of the transfer paper receiving portion of the guide member is narrower than the width of the transfer paper of the minimum paper passing size, and the transfer paper receiving portion of the guide member does not receive both side end portions of the transfer paper. A forming apparatus is disclosed.

JP 2001-97604 A

  SUMMARY OF THE INVENTION An object of the present invention is to provide an image forming apparatus that can make a recording medium difficult to get dirty.

  According to a first aspect of the present invention, there is provided a developer image forming unit that forms a developer image on a recording medium, a fixing device that fixes the developer image formed by the developer image forming unit on a recording medium, and the fixing An image forming apparatus including a developer removing unit that removes unfixed developer adhered to an edge of a recording medium conveyed to the apparatus.

  According to a second aspect of the present invention, the developer removing means contacts the at least the leading edge and the side edge of the recording medium, and removes the unfixed developer from the recording medium. The image forming apparatus according to claim 1, further comprising a member.

  A third aspect of the present invention is the image forming apparatus according to the second aspect, wherein the developer removing member is disposed at a position where a leading end portion of a recording medium that has straightly advanced from the developer image forming portion contacts.

  The present invention according to claim 4 further includes a guide member for guiding a recording medium to the fixing device, wherein the developer removing member is attached to the guide member, and the guide member forms the developer image. 4. The image forming apparatus according to claim 2, wherein the recording medium supplied in a bent state is guided to the fixing device such that a leading end portion does not contact the developer removing member.

  The present invention according to claim 5 further includes a re-conveying device that reverses the recording medium having the developer image fixed on one surface thereof by the fixing device and conveys the recording medium again to the developer forming portion. 4. The image forming apparatus according to any one of 4 above.

  The present invention according to claim 6 further includes a recording medium supply unit that supplies a recording medium to the developer image forming unit, and a control unit that controls at least the developer image forming unit and the recording medium supply unit. The control unit determines the type of the recording medium according to whether or not the developer image forming unit forms a developer image without forming a margin in the vicinity of the end of the recording medium, and the recording medium 6. The image forming apparatus according to claim 1, wherein a recording medium of a specified type is supplied from a supply unit.

  According to the first aspect of the present invention, it is possible to provide an image forming apparatus capable of making a recording medium difficult to get dirty.

  According to the second aspect of the present invention, in addition to the effects of the first aspect of the present invention, an image forming apparatus capable of simplifying the configuration compared to the case without the present configuration. Can be provided.

  According to the third aspect of the present invention, in addition to the effect of the second aspect of the present invention, the developer attached to the edge on the leading end side of the recording medium having high rigidity can be removed. An image forming apparatus can be provided.

  According to the fourth aspect of the present invention, in addition to the effects of the second or third aspect of the present invention, it is possible to provide an image forming apparatus that can make it difficult to cause a conveyance failure of the recording medium. it can.

  According to the present invention of claim 5, in addition to the effects of the present invention of any one of claims 1 to 4, when forming an image on both sides of the recording medium, one side of the recording medium It is possible to provide an image forming apparatus capable of making the other surface on which an image is formed after the image is formed less likely to be stained.

  According to the present invention of claim 6, in addition to the effects of the present invention of any one of claims 1 to 5, image formation on a suitable type of recording medium according to the position where the image is formed An image forming apparatus capable of performing the above can be provided.

1 is a cross-sectional view illustrating an image forming apparatus according to a first embodiment of the present invention from the left side. FIG. 2 is a cross-sectional view showing an image forming structure included in the image forming apparatus shown in FIG. 1 from the left side. FIG. 2 is a cross-sectional view illustrating a guide member and a developer removing member included in the image forming apparatus illustrated in FIG. 1. FIG. 4 is a perspective view showing a guide member and a developer removing member shown in FIG. 3. FIG. 2 is a block diagram illustrating a control unit of the image forming apparatus illustrated in FIG. 1. 2 is a flowchart showing an operation of the image forming apparatus shown in FIG. FIG. 7A is a first diagram illustrating the behavior of a sheet in the image forming apparatus illustrated in FIG. 1, and FIG. 7A is a diagram illustrating the sheet when the leading end of the card reaches the developer removing member. FIG. 7B is a diagram illustrating the sheet when the leading end of the thick sheet passes through the developer removing member. FIG. 8A is a second diagram for explaining the behavior of the paper in the image forming apparatus shown in FIG. 1, and FIG. 8A is a diagram showing the paper when the leading edge of the plain paper reaches the developer removing member; FIG. 8B is a diagram illustrating the paper at the time when the leading edge of the plain paper has passed the developer removing member. FIG. 9 is a cross-sectional view illustrating a guide member included in the image forming apparatus according to the comparative example. FIG. 6 is a diagram for explaining the behavior of a sheet in an image forming apparatus according to a comparative example. FIG. 11A is a diagram illustrating the behavior of a sheet in an image forming apparatus according to a second embodiment of the present invention, and FIG. 11A is a diagram illustrating the sheet when the leading end of the sheet reaches the developer removing member. FIG. 11B is a diagram illustrating the sheet when the leading end of the sheet has passed the developer removing member.

Next, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows an image forming apparatus 10 according to a first embodiment of the present invention. The image forming apparatus 10 includes an image forming apparatus main body 12, a developer image forming unit 100 that forms a developer image on a sheet used as a recording medium, and a developer image formation in the image forming apparatus main body 12. A transfer device 200 for transferring the developer image formed on the sheet to the paper, a fixing device 240 for fixing the developer image formed on the developer image forming unit 100 and transferred to the paper by the transfer device 200 to the paper, A paper feeding device 300 used as a recording medium supply unit that supplies paper (recording medium) to the developer image forming unit 100 is provided.

  In the image forming apparatus main body 12, the main conveyance path 510 and the re-conveyance in which the sheet on which the developer image is formed on one surface is reversed by the fixing device 240 and conveyed to the developer image forming unit 100 again. A reverse conveyance path 562 which is one of the elements constituting the device 560 is formed. In addition, the image forming apparatus 10 includes a control circuit 600 used as a control unit, a brush 620 used as a developer removing member, and a guide member 630 as a developer removing unit. .

  Further, the upper part of the image forming apparatus main body 12 is used as a discharge unit 14 from which paper is discharged. An operation panel 610 used as an operation unit for operating the image forming apparatus 10 is attached to, for example, the front side (right side in FIG. 1) of the image forming apparatus main body 12.

  The developer image forming unit 100 forms a color image, for example, and employs an electrophotographic system. The developer image forming unit 100 includes, for example, four image forming structures 102Y each having a cylindrical photoconductor 110Y, a photoconductor 110M, a photoconductor 110C, and a photoconductor 110K that are used as an image carrier, for example. It includes a forming structure 102M, an image forming structure 102C, an image forming structure 102K, and a latent image forming device 160. Details of the image forming structure 102M, the image forming structure 102C, the image forming structure 102K, and the latent image forming device 160 will be described later.

  The developer image forming unit 100 forms, for example, a margin with a certain width around the edge of the sheet, and forms an image inside the margin, or forms a margin without forming a margin around the edge of the sheet. A developer image can also be formed on the entire surface. For example, when an image such as a photograph is formed, an image is often formed on the entire surface of the paper without forming a margin in the vicinity of the edge of the paper. For example, when an image mainly including characters is formed, In many cases, a margin is formed near the portion, and an image is formed inside the margin. Whether the developer image is formed so as to form a margin in the vicinity of the edge of the sheet or whether the developer image is formed so as not to form a margin on the sheet is controlled by the control circuit 600 according to the operation of the operator, for example. Determined by.

  The latent image forming device 160 includes, for example, a laser exposure device. The photoconductor 110Y converts a laser beam corresponding to a yellow image, the photoconductor 110M generates a laser beam corresponding to a magenta image, and the photoconductor 110C forms a cyan image. Corresponding laser light is emitted to the photoconductor 110K corresponding to a black image, and electrostatic latent images are formed on the photoconductor 110Y, the photoconductor 110M, the photoconductor 110C, and the photoconductor 110K, respectively.

  The transfer device 200 includes a developer image composed of a yellow developer, a developer image composed of a magenta developer, and a cyan developer formed on each of the photoreceptor 110Y, the photoreceptor 110M, the photoreceptor 110C, and the photoreceptor 110K. And a developer image made of a black developer are transferred onto a sheet. The transfer device 200 includes a sheet conveying member 202, a transfer roll 210Y, a transfer roll 210M, a transfer roll 210C, and a transfer roll 210K.

  The sheet conveying member 202 is, for example, a belt-like shape, for example, an endless shape, holds the sheet by, for example, electrostatic adsorption, and conveys the held sheet. The sheet conveying member 202 is supported by, for example, a support roll 204 and a support roll 206 which are two support rolls. At least one of the support roll 204 and the support roll 206 is used as a drive roller that transmits driving to the sheet conveying member 202, and transmits driving to the sheet conveying member 202. The sheet conveying member 202 is shown in FIG. Rotate in the direction of the arrow.

  The transfer roll 210Y, the transfer roll 210M, the transfer roll 210C, and the transfer roll 210K are, for example, the photoconductor 110Y, the photoconductor 110M, the photoconductor 110C, and the photoconductor 110K inside the paper transport member 202 via the paper transport member 202, respectively. It arrange | positions so that it may oppose. Further, a transfer bias is applied to each of the transfer roll 210Y, the transfer roll 210M, the transfer roll 210C, and the transfer roll 210K, and the development formed on the photoconductor 110Y, the photoconductor 110M, the photoconductor 110C, and the photoconductor 110K. The developer image is sequentially transferred onto the sheet being conveyed by the sheet conveying member 202, and the four-color development of the yellow developer image, the magenta developer image, the cyan developer image, and the black developer image is performed on the sheet. A developer image on which the agent images are superimposed is formed.

  When the developer is transferred to the paper by the transfer device 200, if the developer image is formed so that an image is formed on the entire surface of the paper by the developer image forming unit 100, the development that originally forms the developer image is performed. The developer may adhere not only to the transfer surface of the paper at which the agent should be transferred, but also to the edge (thickness portion) of the paper.

  The fixing device 240 includes a heating roll 242 having a heat source therein and a pressure roll 244 pressed against the heating roll 242, and the image is transferred to a sheet at a contact portion between the heating roll 242 and the pressure roll 244. The developer is heated and pressurized to fix the developer image formed by the developer image forming unit 100 on the paper.

  The paper feeding device 300 supplies paper to the developer image forming unit 100. The paper feeding device 300 includes a first paper feeding device 310 and a second paper feeding device 330. The first paper feeding device 310 and the second paper feeding device 330 can store sheets having different thicknesses, sizes, etc., and the developer image forming unit 100 can store sheets having different thicknesses, sizes, etc. Can be supplied to. In the following description, the first paper feeding device 310 is often used when, for example, forming an image such as a photograph, and is thicker than the paper stored in the second paper feeding device 330 ( Hereinafter, the second paper feeding device 330 is often used for forming a character image, and the thick paper contained in the first paper feeding device 330 is stored in the second paper feeding device 330. A case where a sheet having a smaller thickness (hereinafter referred to as “plain paper”) is stored will be described as an example.

  The first paper feeder 310 includes a paper storage container 312. In the paper storage container 312, for example, paper such as thick paper is stored so as to be stacked, and the paper storage container 312 can be pulled out or removed from the image forming apparatus main body 12, for example, forward. . In addition, the first paper feeder 310 has a delivery roll 314 that delivers paper from the paper storage container 312.

  The second paper feeder 330 has a paper storage container 332. The paper storage container 332 stores, for example, sheets of plain paper or the like so that the paper storage container 332 can be pulled out or removed from the image forming apparatus main body 12, for example, to the front side. Yes. Further, the second paper feeding device 330 has a feed roll 334 that feeds paper from the paper storage container 332.

  The main conveyance path 510 is a conveyance path used when conveying a sheet so that the sheet is conveyed from the sheet feeding device 300 toward the transfer device 200 and discharged from the transfer device 200 to the discharge unit 14. Along the main conveyance path 510, in order from the upstream side in the sheet conveyance direction, the sheet feeding device 300, the resist roll 514, the developer image forming unit 100 and the transfer device 200, and the fixing device 240 described above. A discharge roll 518 is disposed.

  The resist roll 514 temporarily stops the movement of the leading edge of the sheet conveyed toward the developer image forming unit 100 and the transfer device 200 toward the developer image forming unit 100 and the transfer device 200, The movement of the leading edge of the sheet toward the developer image forming unit 100 and the transfer device 200 is resumed so as to coincide with the timing at which the developer images are formed on the bodies 110Y, 110M, 110C, and 110K.

  The discharge roll 518 is configured to switch the rotation direction, and discharges the sheet conveyed from the fixing device 240 to the discharge unit 14 by rotating in one direction. The discharge roll 518 rotates in the other direction to pull in the sheet from the discharge unit 14 side into the image forming apparatus main body 12 and supply the sheet to the reverse conveyance path 562.

  The reverse conveyance path 562 is used for reversing the sheet on which the developer image is fixed on one surface by the fixing device 240 and conveying the sheet again to the developer image forming unit 100, from the discharge roll 518 to the registration roll. The sheet is conveyed to the upstream side of 514. Further, for example, three reverse transfer rolls 564 are arranged along the reverse transfer path 562. A re-transport device 560 is configured by the reverse transport path 562 and, for example, three reverse transport rolls 564.

  When an image is formed on the other side of the paper on which the image is formed on one side, the discharge roll 518 inverts the paper with the discharge roll 518 in contact with the vicinity of the rear end of the paper on which the image is formed. The rotation in the direction of feeding to the conveyance path 562 is started, and by this rotation, the paper is supplied from the rear end side to the reverse conveyance path 562, and the supplied paper is upstream of the registration roll 514 by the three reverse conveyance rolls 564. Be transported.

  The guide member 630 guides the sheet from the developer image forming unit 100 to the fixing device 240. The brush 620 is attached to the guide member 630, for example. Details of the brush 620 and the guide member 630 will be described later.

In FIG. 2, an imaging structure 102 is shown.
Since the image forming structure 102Y, the image forming structure 102M, the image forming structure 102C, and the image forming structure 102K have the same configuration although the colors of the developer images to be formed are different, the image forming structure 102 will be described below. And will be described collectively. As shown in FIG. 2, the image forming structure 102 includes an image forming structure main body 104, and the above-described photoconductor 110 and the photoconductor 110 are uniformly charged in the image forming structure main body 104. A charging device 114, a developing device 116 for developing the latent image formed on the photoconductor 110 by the latent image forming device 160 (see FIG. 1) using a developer, and a developer image by the transfer device 200 (see FIG. 1). And a cleaning device 118 for cleaning the developer and the like remaining on the photoconductor 110 after the transfer is performed.

  The image forming structure main body 104 is formed with a laser beam path 106 extending from one end portion in the horizontal direction to the vicinity of the other end portion, and the laser beam emitted from the latent image forming device 160 passes through the laser beam path 106. The photosensitive member 110 is reached.

3 and 4 show a guide member 630 and a brush 620. FIG.
The guide member 630 is manufactured, for example, by bending a metal plate. Further, for example, three holes 632 used for attaching the guide member 630 to the image forming apparatus main body 12 using, for example, screws (not shown) or the like are formed in the guide member 630. Further, the guide member 630 has a guide surface 634 used for guiding the paper. The guide surface 634 is a substantially flat surface, for example. Further, when the guide member 630 is attached to the image forming apparatus main body 12, the guide surface 634 has an extended surface that contacts the heating roll 242 (see FIG. 1) and the pressure roll 244 (see FIG. 1). It is formed in the direction extending toward

  Further, the guide member 630 has a recess 636 that is recessed with respect to the guide surface 634 on the opposite side of the main transport path 510 (see FIG. 1).

  The brush 620 is used as a developer removing unit that removes the developer attached to the edge of the sheet conveyed to the fixing device 240 (see FIG. 1), and at least the edge and side edges on the leading end side of the sheet. This is used as a developer removing member that comes into contact with the side edge and removes the developer from the paper, and is attached to the recess 636 so that the hair ends of the bristle face the main conveyance path 510 side. In addition, the brush 620 has all the main conveyance path 510 with respect to the virtual surface 642 including the end 638 on the fixing device 240 side of the guide member 630 and the end 640 on the end 638 side of the guide surface 634. It is arrange | positioned so that it may be located on the opposite side.

  The brush 620 has a width L1 in a direction intersecting with the direction in which the sheet is conveyed larger than the width L2 of the longest sheet P used in the image forming apparatus 10, and the sheet P passes when the sheet P passes through. Are disposed at positions passing through the inside of the brush 620 in a direction intersecting with the direction in which the sheet is conveyed. Further, the brush 620 can use a hair material made of a resin as a hair material. More specifically, as the hair material, for example, rayon, nylon, acetate, copper ammonia, vinylidene, vinylon, fluorinated ethylene, A hair material made of benzoate, polyurethane, polyester, polyethylene, polyvinyl chloride, polypropylene or the like can be used.

FIG. 5 is a block diagram showing the control circuit 600.
As shown in FIG. 5, image data is input to the control circuit 600 via the communication interface 602. Further, the control circuit 600 receives an input from the operation panel 610, and at least the developer image forming unit 100, the first paper feeding device 310, and the second paper feeding device 330 according to the output from the control circuit 600. Is controlled.

FIG. 6 is a flowchart showing the operation of the image forming apparatus 10.
As shown in FIG. 6, when a series of operations is started, the control circuit 600 receives image data input from the communication interface 602 and input from the operation panel 610 in step S100, which is the first step. Based on this, it is determined whether or not the next image forming mode is the borderless mode. Here, the borderless mode refers to a mode in which a developer image is formed on the entire surface of the paper without forming a margin in the vicinity of the edge of the paper. If it is determined in step S100 that the frameless mode is selected, the process proceeds to step S120. If it is determined in step S100 that the frameless mode is not selected, the process proceeds to step S110.

  In step S110, the control circuit 600 causes the developer image forming unit 100 to form a developer image in the normal mode. Here, the normal mode is a mode in which, for example, a margin with a certain width is formed in the vicinity of the edge of the sheet, and an image is formed inside the margin. Further, in step S110, the control circuit 600, for example, from the first paper feeding device 310 or the second paper feeding device 330 in response to an input from the operation panel 610, the developer image forming unit 100. Feed the paper toward. At this time, the first paper feeding device 310 supplies the thick paper stored in the paper storage container 312 to the developer image forming unit 100, and the second paper feeding device 330 is a normal paper stored in the paper storage container 332. The paper is supplied to the developer image forming unit 100. In this way, in the normal mode, an image is formed on any one of paper selected from thick paper and plain paper.

  In step S110, for example, an image is formed on one or both sides of the sheet in response to an input from the operation panel 610. When step S110 ends, the process proceeds to the next step S130.

  In step S120, the control circuit 600 causes the developer image forming unit 100 to form a developer image in the borderless mode. In step S <b> 110, the control circuit 600 supplies paper from the first paper feeder 310 toward the developer image forming unit 100. At this time, the first paper feeder 310 supplies the thick paper stored in the paper storage container 312 to the developer image forming unit 100. The image forming apparatus 10 is configured so that an image is formed on thick paper exclusively when the borderless mode is selected. When the borderless mode is selected, an image cannot be formed on plain paper. It is like that.

  In step S120, similarly to step S110, for example, an image is formed on one or both sides of the sheet in response to an input from operation panel 610. When step S110 ends, the process proceeds to the next step S130. As shown in the description of step S110 and step S120, the control circuit 600 determines whether the developer image forming unit 100 forms a developer image without forming a margin near the end of the sheet. The type of the paper is determined, and the paper is supplied from the paper feeding device 300 toward the developer image forming unit 100.

  In the next step S130, it is determined whether or not the processed image data is the last image data in the group of image data input via the communication interface 602, and it is determined that the processed image data is not the last data. If YES in step S100, the process returns to step S100. If it is determined that the data is the last data, the series of processes is terminated.

FIG. 7 illustrates the behavior of the thick paper P <b> 1 when the thick paper is supplied from the first paper feeder 310.
As shown in FIG. 7A, when the leading end of the thick paper P1 is separated from the paper conveying member 202, the thick paper P1 advances straight without being bent due to the rigidity of the paper (paper stiffness). Here, the brush 620 is disposed at a position where the leading edge of the sheet that has traveled straight from the developer image forming unit 100 contacts. For this reason, the leading end of the thick paper P1 comes into contact with the brush 620, and the developer attached to the edge on the leading end side of the thick paper P1 is removed from the thick paper P1. Here, the edge of the thick paper P1 refers to the thick portion of the paper, not the surface on which the image of the thick paper P1 is formed.

  When the thick paper P1 is sent out to the guide member 630 side by the paper conveying member 202 from the state shown in FIG. 7A, the tip of the thick paper P1 separates the brush 620 as shown in FIG. 7B. Then, it is guided to the fixing device 240. At this time, both sides of the cardboard P1 are in contact with the brush 620 (see FIG. 4). For this reason, the developer attached to the edge portion on the side end portion side of the thick paper P1 is removed by the brush 620.

  As described above, before the thick paper P <b> 1 is supplied to the fixing device 240, the developer adhering to the edge on the leading edge side and the edge on the side edge side of the thick paper P <b> 1 is removed by the brush 620. Therefore, the developer is less likely to adhere to the fixing device 240, and the paper is less likely to be smeared due to the developer being adhered to the fixing device 240.

FIG. 8 illustrates the behavior of the plain paper P <b> 2 when plain paper is supplied from the second paper feeding device 330.
As shown in FIG. 8A, the plain paper from the curved portion by being supported by the support roll 206 of the paper carrying member 202 against the force of adsorbing the plain paper P <b> 2 of the paper carrying member 202. When the leading end of P2 is separated, the plain paper P2 advances in the direction of the guide member 630 while being bent in the direction of the paper conveying member 202. The leading end of the plain paper P2 comes into contact with the guide surface 634 of the guide member 630.

  When the plain paper P2 is sent out to the guide member 630 side by the paper transport member 202 from the state shown in FIG. 8A, the leading end of the plain paper P2 is placed on the guide surface 634 as shown in FIG. The plain paper P2 is guided to the fixing device 240 so as to slide on the surface. Here, as described above, the brush 620 is formed on the virtual surface 642 (see FIG. 3) including the end 638 on the fixing device 240 side of the guide member 630 and the end 640 on the end 638 side of the guide surface 634. On the other hand, all the portions are arranged so as to be located on the opposite side to the main conveyance path 510. For this reason, the plain paper P <b> 2 is guided to the fixing device 240 without contacting the brush 620. For this reason, the conveyance failure of the paper caused by the leading end portion of the plain paper P2 being caught by the brush 620 hardly occurs, and the developer or the like attached to the brush 620 is difficult to adhere to the paper.

FIG. 9 shows a guide member 630 included in the image forming apparatus according to the comparative example.
The image forming apparatus 10 according to the first embodiment of the present invention has the brush 620 and the brush 620 is attached to the guide member 630. On the other hand, the image forming apparatus according to the comparative example does not have the brush 620. The configuration of the image forming apparatus according to the comparative example is the same as that of the image forming apparatus 10 according to the first embodiment described above except that the brush 620 is not provided and the shape of the guide member 630 is different.

FIG. 10 illustrates the behavior of the thick paper P1 when the thick paper is supplied from the first paper feeding device 310 in the image forming apparatus according to the comparative example.
As shown in FIG. 10A, when the leading end of the thick paper P1 is separated from the paper conveying member 202, the thick paper P1 advances straight without being bent due to the rigidity of the paper (the stiffness of the paper), and the thick paper P1. The tip of the contact portion comes into contact with the guide member 630. When the thick paper P1 comes into contact with the guide member 630, the developer attached to the edge of the thick paper P1 is separated from the thick paper P1 due to an impact or the like. Then, since the separated developer goes around the back surface of the thick paper P1 and adheres to the back surface of the thick paper P1, the thick paper P1 becomes dirty.

  Further, the developer separated from the thick paper P1 adheres to the guide member 630. The developer adheres to the guide member 630 and then adheres to the sheet supplied to the guide member 630, and the sheet is stained. Further, the developer adhered to the pressure roll 244 by the developer adhered to the back side of the thick paper P1, and the developer adhered to the pressure roll 244 adheres to the sheet supplied to the fixing device 240 next, and The paper is dirty.

FIG. 11 shows a main part of an image forming apparatus 10 according to the second embodiment of the present invention.
In the image forming apparatus 10 according to the first embodiment described above, the sheet conveying member 202 conveys the sheet from the lower side to the upper side in the gravity direction, and the fixing device 240 is located above the developer image forming unit 100 in the gravity direction. Had been placed. On the other hand, in the image forming apparatus 10 according to the second embodiment, as shown in FIG. 11, the sheet conveying member 202 conveys the sheet substantially horizontally, and the fixing device 240 is the developer. The image forming unit 100 is disposed on the side of the image forming unit 100 and on the downstream side of the developer image forming unit 100 in the sheet conveyance direction.

  As shown in FIG. 11A, also in the image forming apparatus 10 according to the second embodiment, the thick paper P1 comes into contact with the brush 620 and is conveyed to the fixing device 240. At the previous position, the developer is removed from the edge on the front end side and the edge on the side end side of the cardboard P1.

  Further, as shown in FIG. 11B, in the image forming apparatus 10 according to the second embodiment, the plain paper P2 is guided by the guide surface 634 so as not to contact the brush 620. To the fixing device 240.

  As described above, the present invention can be used at least for an image forming apparatus such as a printer, a facsimile machine, and a copying machine, and for example, a transport apparatus that can be applied to these image forming apparatuses.

DESCRIPTION OF SYMBOLS 10 ... Image forming apparatus 100 ... Developer image forming part 240 Fixing device 310 1st paper feeding apparatus 330 2nd paper feeding apparatus 560 Re-conveyance apparatus 562 Reverse conveyance path 600 Control circuit 620 Brush 630 Guide member 634 Guide surface 636 Recess P1 Thick paper P2 Plain paper

Claims (4)

A developer image forming unit for forming a developer image on a recording medium;
A fixing device for fixing the developer image formed by the developer image forming unit to a recording medium;
Developer removing means for removing unfixed developer attached to the edge of the recording medium conveyed to the fixing device;
I have a,
The developer removing means has a developer removing member that contacts at least the edge on the front end side and the edge on the side end side of the recording medium and removes the unfixed developer from the recording medium,
The image forming apparatus , wherein the developer removing member is disposed at a position where a leading end portion of a recording medium that has traveled straight from the developer image forming portion contacts . A guide member for guiding the recording medium to the fixing device;
The developer removing member is attached to the guide member,
The guide member, a recording medium fed in a bent state from the developer image forming unit, the image formation according to claim 1, wherein the tip is guided to the fixing device so as not to contact the developer removing member apparatus. The fixing by reversing the recording medium on which the developer image is fixed on one side by the device, an image forming apparatus according to claim 1 or 2, wherein further comprising a re-conveying device for conveying back to the developer forming unit. A recording medium supply unit for supplying a recording medium to the developer image forming unit;
A control unit for controlling at least the developer image forming unit and the recording medium supply unit;
Further comprising
The control unit determines the type of the recording medium according to whether or not the developer image forming unit forms a developer image without forming a margin in the vicinity of the end of the recording medium, and the recording medium supply unit the image forming apparatus according to any one of claims 1 to 3 to supply the recording medium type is determined from.

Images