JP3751859B2 - Transport guide for image forming apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a conveyance guide for guiding a recording material after completion of a transfer process in an image forming unit to a post-processing unit such as a fixing unit in an image forming apparatus that performs electrophotographic image formation such as a copying machine, a printer, or a facsimile.
[0002]
[Prior art]
Conventionally, in an electrophotographic image forming apparatus, after a developer image carried by an image carrier such as a photosensitive drum provided in an image forming unit is transferred onto a recording material such as paper or an OHP film, The recording material is heated and / or pressurized to fix the developer image on the surface of the recording material, thereby obtaining an image formed product. In such an image forming apparatus, a conveyance guide for guiding the recording material from the image forming unit to the fixing unit is provided between the image forming unit and the fixing unit.
[0003]
In particular, in an image forming apparatus that changes the state of the image forming unit according to the image forming mode, there is one in which the discharge position of the recording material from the image forming unit is displaced in the vertical direction according to the image forming mode. In such an image forming apparatus, a movable conveyance guide is provided to guide the recording material to the fixing unit.
[0004]
[Problems to be solved by the invention]
However, when the length of the movable conveyance guide in the recording material conveyance direction is short, if the amount of displacement in the vertical direction of the recording material ejection position from the image forming unit is large, the recording material ejected from the image forming unit The distance in the vertical direction from the transport guide increases, or a depression that protrudes downward occurs in the transport path at the contact portion between the tip of the movable transport guide and the fixed transport guide, and the front end of the recording material is large. It curls and cannot be smoothly guided to the fixing portion. In particular, when the recording material is not evenly spaced from the image forming unit in the direction orthogonal to the recording material conveyance direction, the bending state of the front end of the recording material in the direction orthogonal to the conveyance direction becomes non-uniform, It becomes easy to generate wrinkles and creases on the recording material. As described above, when wrinkles or creases occur in the recording material passing through the fixing unit, not only the quality of the image formed product is deteriorated but also the recording material is jammed in the fixing unit.
[0005]
For example, a plurality of image forming units having different image forming colors are arranged in the recording material conveying direction with the black image forming unit being the most upstream side, and a transfer conveying belt is stretched below these image forming units. In the color image forming mode in which all the image forming units are used in the image forming apparatus, the upper surface of the transfer conveyance belt 216 is substantially horizontal as shown in FIG. 6, while the image forming unit other than the black image forming unit is formed. In the monochrome image forming mode in which no part is used, the downstream side of the transfer conveyance belt 216 is displaced downward as shown in FIG.
[0006]
In such an image forming apparatus, the other end of the movable conveyance guide 21 having one end pivotally supported at the downstream end of the frame 213b that supports the transfer conveyance belt 216 is located upstream of the fixing device 217 constituting the fixing unit. When contacting the vicinity of the upstream end on the upper surface of the fixed guide member 22, the inclination angle of the upper surface of the conveyance guide 21 matches the inclination angle of the upper surface of the guide member 22 in the monochrome image forming mode shown in FIG. Then, in the color image forming mode, as shown in FIG. 6, the discharge direction (XX direction) of the recording material P from the transfer conveyance belt 216 is set with the upper surface of the transfer conveyance belt 216 being substantially horizontal. The distance in the vertical direction between the upper surface of the conveyance guide 21 and the portion with which the leading end of the flexible recording material P abuts increases, and the curl amount (deformation amount) at the leading end of the recording material P increases. Kikunaru. Further, at the portion S where the other end of the conveyance guide 21 abuts on the upper surface of the guide member 22, a depression is formed in the conveyance path of the recording material P due to an angle change between the upper surface of the conveyance guide 21 and the upper surface of the guide member 22. The leading end of the recording material P is fitted in this portion, and the conveyance state of the recording material P becomes more unstable.
[0007]
It is an object of the present invention to make the recording discharged from the image forming unit even when the position of the recording material in the vertical direction from the image forming unit is displaced according to the image forming mode by making the shape of the conveyance guide appropriate. Image formation that can always smoothly guide the material to the post-processing section such as the fixing section, and can prevent deterioration of the quality of the image formation due to the occurrence of wrinkles and creases, and deterioration of the operation efficiency due to the occurrence of jam. It is to provide a transport guide for the apparatus.
[0008]
[Means for Solving the Problems]
The present invention has the following configuration as means for solving the above problems.
[0009]
  (1) A flat plate shape that is supported in a swingable manner with one end portion as a fulcrum in the vicinity of the downstream end portion of the image forming portion in which the downstream end portion in the recording material conveyance direction is displaced in the vertical direction according to the image forming mode. In the conveyance guide of the image forming apparatus that contacts the bottom surface of the recording material that has passed through the image forming unit and guides the recording material to the post-processing unit,
  A guide member fixed near the recording material entry position in the post-processing section and facing the lower surface of the recording material;
  The lower surface of the other end is always in contact with the upper surface of the guide member,The other end isSaidNearest recording material entry position in post-processing sectionAt the bottomIt is supported from the side.
[0010]
  In this configuration,The lower surface of the other end portion of the conveyance guide whose one end portion is pivotally supported by the downstream end portion of the image forming unit abuts on the upper surface of the guide member fixed immediately near the recording material entry position in the post-processing unit. Therefore, the other end of the conveyance guide is reliably supported by the guide member immediately in the vicinity of the recording material entry position in the post-processing unit, and the vertical position of the downstream end of the image forming unit is displaced according to the image forming mode. Even in this case, the other end portion of the conveyance guide does not change from the position immediately before the recording material entry position in the post-processing portion. In addition, the upper surface of the conveyance guide is continuous with the upper surface of the guide member in the immediate vicinity of the recording material entry position in the post-processing section. Therefore, the conveyance of the recording material discharged from the image forming unit is inherited from the conveyance guide to the guide member immediately near the recording material entry position in the post-processing unit, and the recording material is smoothly guided into the post-processing unit.It is.
[0011]
(2) The post-processing unit is a fixing unit in which a recording material enters a press-contact portion between a pair of rotating members.
[0012]
In this configuration, the downstream end of the image forming unit and the closest position of the recording material entering position in the fixing unit are communicated with each other by a single flat plate-shaped conveyance guide. Accordingly, the downstream end portion of the image forming unit is opposed to the fixing unit that is likely to be wrinkled or bent due to a change in the conveyance state after being discharged from the image forming unit in order to receive the pressure by the pair of rotating members. Regardless of the vertical position, the recording material always enters in a stable state.
[0013]
  (3) The aboveThe contact position of the lower surface of the other end on the upper surface of the guide member changes according to the displacement of the image forming unit.It is characterized by doing.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a schematic diagram showing the configuration of a digital color copying machine which is an image forming apparatus to which a conveyance guide according to an embodiment of the present invention is applied. An upper part of the digital color copying machine 1 is provided with an original reading unit 110 having a hard transparent glass platen 111 arranged on the upper surface. The upper surface of the document table 111 is covered with a double-sided automatic document feeder (hereinafter referred to as RADF (Recirculating Automatic Document Feeder)) 112 so as to be freely opened and closed. The RADF 112 conveys the original so that one side of the original faces the original reading unit 110 at a predetermined position on the original platen 111, and in the double-sided reading mode, after the image reading on one side of the original is completed, The document is inverted and conveyed toward the document table 111 so that the surface of the document table 111 faces the document reading unit 110 at a predetermined position on the document table 111. In the double-sided reading mode, the RADF 112 discharges the original after completing the double-sided image reading for one original, and executes the double-sided conveyance operation for the next original. The double-sided conveyance operation in the RADF 112 is controlled in relation to the operation of the entire digital color copying machine 1.
[0016]
The document reading unit 110 includes scanning units 113 and 114, a lens 115, and a photoelectric conversion element (hereinafter referred to as a CCD) 116. The scanning units 113 and 114 reciprocate at a predetermined speed parallel to the lower surface of the document table 111, and the reflected light from the document placed on the upper surface of the document table 111 is irradiated from the light source lamp mounted on the scanning unit 113. Is distributed to the lens 115 with a constant optical path length. The lens 115 forms an image of the reflected light from the original on the light receiving surface of the CCD 116. The CCD 116 can read a monochrome image or a color image from an original, and can output line data that is color-separated into each color component of red (R), green (G), and blue (B), which are three additive primary colors. This is a line color CCD, and outputs a light reception signal corresponding to the amount of light reflected from the light receiving surface from the original. The received light signal output from the CCD 116 is converted into digital data by an image processing unit (not shown) and then subjected to predetermined image processing.
[0017]
In the digital color copying machine 1, an image forming unit 210 is provided below the document reading unit 110. The image forming unit 210 includes four image forming stations 10a to 10d arranged in a line in the conveying direction of a recording material such as paper. Below the image forming unit 210, recording paper (including recording materials other than paper such as an OHP film) P stored in a paper tray is separated and supplied to the image forming unit 210 one by one. A sheet feeding mechanism 211 is provided. Then, the recording paper P separated and supplied one by one is transported to the image forming unit 210 with the timing controlled by a pair of registration rollers 212 arranged in front of the image forming unit 210. Further, in the double-sided copying mode, the recording paper P on which an image is formed on one side is formed in accordance with the timing of image formation by the image forming unit 210 in a state where the front and rear in the transport direction are reversed in the switchback transport path 221. The paper is conveyed again to the section 210.
[0018]
In the image forming unit 210, a transfer conveyance belt unit 213 is disposed below each of the image forming stations 10a to 10d. The transfer / conveyance belt unit 213 is configured to convey the recording paper P by electrostatically attracting the transfer / conveyance belt 216 stretched between the driven roller 214 and the driving roller 215 in a substantially parallel manner. Further, a fixing device 217 for fixing the toner image transferred onto the recording paper P onto the recording paper P is disposed on the downstream side of the transfer / conveying belt unit 213 in the paper conveying path. The fixing device 217 constitutes a fixing unit that is a post-processing unit of the present invention.
[0019]
The recording paper P that has passed through the nip portion between the pair of rollers of the fixing device 217 passes through the switching gate 218 and is discharged onto the paper discharge tray 220 attached to the outer wall of the digital color copying machine 1 by the discharge roller 219. . The switching gate 218 includes a transport path for the recording paper P after fixing, a path for discharging the recording paper P to the paper discharge tray 220, and a path for re-supplying the recording paper P to the image forming unit 210 via the switchback transport path 221. Selectively switch between. The recording paper P whose transport direction has been switched toward the image forming unit 210 by the switching gate 218 is supplied again to the image forming unit 210 with the front and back surfaces reversed while passing through the switchback transport path 221. The
[0020]
Further, the transfer conveyance belt 216 is frictionally driven in the direction indicated by the arrow Z in the figure by the driving roller 215, and sequentially conveys the recording paper P adsorbed on the upper surface to the image forming stations 10a to 10d.
[0021]
Each of the image forming stations 10a to 10d has the same configuration. As an example, the image forming station 10a exposes the surface of the photosensitive drum 222a and the charger 223a that uniformly charges the surface of the photosensitive drum 222a around the photosensitive drum 222a that is rotationally driven in the direction of the arrow. An exposure unit 227a that forms an electrostatic latent image, a developing device 224a that visualizes the electrostatic latent image formed on the surface of the photosensitive drum 222a into a toner image, and a toner image carried on the surface of the photosensitive drum 222a A transfer roller 225a for transferring to the material and a cleaner 226a for removing the toner remaining on the surface of the photosensitive drum 222a are sequentially arranged. The charger 222a includes a static eliminator that removes charges remaining on the surface of the photosensitive drum 222a on the upstream side in the rotation direction of the photosensitive drum 222a. With this configuration, an image forming process including charging, exposure, development, transfer, and charge removal steps is performed on the surface of the photosensitive drum 222a.
[0022]
An exposure unit 227a provided in the image forming station 10a is a semiconductor laser (not shown) that emits laser light modulated based on image data, and polarizes laser light emitted from the semiconductor laser in the main scanning direction. Polygon mirror 240a, fθ lens 241a that forms an image of the laser light polarized by polygon mirror 240a on the surface of photosensitive drum 222a, and mirrors 242a and 243a that form an optical path from the semiconductor laser to the surface of photosensitive drum 222a. It has. An exposure unit including an LED array and an imaging lens array can also be used.
[0023]
The developing devices 224a to 224d provided in each of the image forming stations 10a to 10d store toners of respective colors of black (K), cyan (C), magenta (M), and yellow (Y) in order. Each of the units 227a to 227d receives image data of each color of K, C, M, and Y in order. Accordingly, in each of the image forming stations 10a to 10d, toner images of K, C, M, and Y colors are formed on the surface of the photosensitive drum 1.
[0024]
In the image forming stations 10a to 10d, the above-described transfer conveyance belt 216 passes between the photosensitive drums 222a to 222d and the transfer rollers 225a to 225d. Accordingly, the transfer rollers 225a to 225d are opposed to the surfaces of the photosensitive drums 222a to 222d with the transfer conveyance belt 216 interposed therebetween. The transfer conveyance belt 216 is charged with static electricity by contact with the charger 228 on the upstream side of the image forming station 10a in the arrow Z direction, and the recording paper P fed from the paper feeding unit 221 is electrostatically attracted to the upper surface. In this state, the image forming stations 10a to 10d are conveyed in synchronization with the rotation of the photosensitive drums 222a to 222d.
[0025]
During the color image forming process based on the color image information, image data of each color of K, C, M, and Y is input to the exposure units 227a to 227d of the image forming stations 10a to 10d. As a result, in each of the image forming stations 10a to 10d, toner images of K, C, M, and Y are formed on the surfaces of the photosensitive drums 222a to 222d, and the recording paper P sequentially passes through the image forming stations 10a to 10d. In the meantime, K, C, M, and Y toner images are sequentially transferred onto the recording paper P.
[0026]
In the monochrome image forming process based on the monochrome image information, K (black) image data is input only to the exposure unit 227a of the image forming station 10a. As a result, a K (black) toner image is formed on the surface of the photosensitive drum 222a at the image forming station 10a, and the K (black) toner image is recorded while the recording paper P passes through the image forming station 10a. Transferred onto the paper P.
[0027]
The recording paper P that has passed through the image forming stations 10 a to 10 d is guided to the fixing device 217. The fixing device 217 heats and presses the recording paper P, melts the toner image, and firmly fixes the toner image on the surface of the recording paper P. As a result, during the color image forming process, a color image is formed on the surface of the recording paper P by subtractive color mixing of toner images of K, C, M, and Y colors. In the monochrome image forming process, a monochrome image is formed on the surface of the recording paper P using a K (black) toner image.
[0028]
The transfer conveyance belt 216 faces the charge eliminator 229 on the downstream side of the image forming station 10d in the arrow Z direction, and the static electricity that has electrostatically attracted the recording paper P is discharged by the charge eliminator 229. Further, the conveyance guide 11 of the present invention is disposed between the transfer conveyance belt 216 and the fixing unit 217. As a result, after passing through the image forming station 10 d, the recording paper P is separated from the transfer conveyance belt 216, guided by the conveyance guide 11, and guided into the fixing device 217.
[0029]
2 and 3 are diagrams showing the configuration and operation of the main part of the image forming unit in the digital color copying machine. In the image forming unit 210 of the digital color copying machine 1, the transfer / conveying belt unit 213 is configured in an upstream frame 213a and a downstream frame 213b. The driven roller 232, the driving roller 215, and the transfer roller 225a are pivotally supported by the upstream frame 213a, and the driven roller 214, the driven roller 231 and the transfer rollers 225b to 225d are pivotally supported by the downstream frame 213b. Further, the driven roller 233 is pivotally supported by the upstream frame 213a, and the rotation shaft passes through the downstream frame 213b.
[0030]
Further, the upstream frame 213a is fixed in the digital color copying machine 1, and the downstream frame 213b is swingably supported by the upstream frame 213a around the rotation axis of the driven roller 233. A long hole 237 is formed in the intermediate portion of the downstream frame 213b, and an eccentric cam 236 fixed to the motor shaft 235a of the motor 235 is fitted into the long hole 237. When the motor 235 is driven, the eccentric cam 236 rotates together with the motor shaft 235 a, and the position of the convex portion of the eccentric cam 236 in the long hole 237 changes, so that the downstream frame 213 b is centered on the rotation axis of the driven roller 233. Swing. The swing position of the downstream frame 213b is detected by the sensor 234.
[0031]
In the color image forming mode in which the image forming process is executed in all of the image forming stations 10a to 10d, as shown in FIG. 2, the downstream frame 213b is positioned at the upper limit position defined by the action of a stopper (not shown). . In this state, the transfer rollers 225b to 225d are in a horizontal position together with the transfer roller 225a. In all of the image forming stations 10a to 10d, the transfer conveyance belt 216 includes the photosensitive drums 222a to 222d and the transfer rollers 225a to 225d. Is sandwiched between. As a result, K, C, M, and Y toner images formed on the surfaces of the photosensitive drums 222a to 222d on the recording paper P placed on the upper surface of the transfer conveyance belt 216 in the image forming stations 10a to 10d, respectively. Are transcribed in order.
[0032]
On the other hand, in the monochrome image forming mode in which the image forming process is executed only in the K (black) image forming station 10a and the image forming processes are not executed in the other C, M, and Y image forming stations 10b to 10d. As shown in FIG. 4, the sensor 234 is positioned at the lower limit position defined by detecting the downstream end of the downstream frame 213b. In this state, the transfer rollers 225b to 225d are positioned below the transfer roller 225a, and the transfer conveyance belt 216 is sandwiched between the photosensitive drum 222a and the transfer roller 225a only in the image forming station 10a. . As a result, only the K toner image formed on the surface of the photosensitive drum 222a in the image forming station 10a is transferred to the recording paper P placed on the upper surface of the transfer conveyance belt 216.
[0033]
In this way, by changing the swing position of the downstream frame 213b in the transfer conveyance belt unit 213 according to the image forming mode to be executed, the image forming process is not executed in the monochrome image forming mode. In the image forming stations 10b to 10d, the transfer / conveying belt 216 is prevented from coming into contact with the photosensitive drums 222b to 222d, and the life of the photosensitive drums 222b to 222d is prevented from being wasted.
[0034]
However, when the downstream frame 213b swings around the vicinity of the upstream end in the transfer conveyance belt unit 213 according to the image forming mode to be executed, the vertical position of the downstream end depends on the image forming mode. As a result, the conveyance path of the recording paper P from the image forming unit 210 to the fixing device 217 changes. At this time, if a significant change occurs in the conveyance state of the recording paper P that is separated from the transfer conveyance belt 216 and discharged from the image forming unit 210, the recording paper P is heated and pressurized to melt and fix the toner image. When the recording paper P passes through the fixing device 217, wrinkles and folds are generated to deteriorate the quality of the image formed product, or jamming occurs in the fixing device 217 to reduce the operation efficiency.
[0035]
Therefore, in the present invention, by considering the shape of the conveyance guide 11 that defines the conveyance direction of the recording paper P between the transfer conveyance belt unit 213 of the image forming unit 210 and the fixing device 217 as the post-processing unit, Even when the vertical position of the downstream end of the transfer / conveyance belt unit 213 is displaced according to the image forming mode to be executed, the recording paper is always kept stable without causing a large change in the conveyance state of the recording paper P. P can be guided into the fixing device 217, so that the image formed product can be maintained in high quality, and a reduction in operating efficiency can be prevented.
[0036]
4 and 5 are diagrams for explaining the configuration and operation of the transport guide according to the embodiment of the present invention. As shown in FIG. 1, the conveyance guide 11 of the present invention is interposed between the transfer conveyance belt unit 213 arranged in the image forming unit 210 of the color copying machine 1 and the fixing device 217 as the post-processing unit. Has been placed. The conveyance guide 11 has a substantially flat plate shape, and is swingably supported at the downstream end of the downstream frame 213b of the transfer conveyance belt unit 213 at one end on the upstream side in the conveyance direction of the recording paper P. On the other hand, the other end of the downstream side of the conveyance guide 11 has the lower surface of the guide member 12 in the immediate vicinity of the pressure contact position between the heating roller 217a and the pressure roller 217b, which is the entry position of the recording paper P in the fixing device 217. It is supported in contact with the upper surface.
[0037]
With this configuration, in the color image forming mode in which the downstream end of the downstream frame 213b is positioned at the upper limit position in the transfer conveyance belt unit 213, as shown in FIG. 4, the extension line direction of the upper surface of the transfer conveyance belt 216 The leading end of the recording paper P comes into contact with the vicinity of the intersection between the discharge direction (XX direction) of the recording paper P and the upper surface of the transport guide 11. From the contact position to the position immediately before the entry position of the recording paper P in the fixing device 217, the transport path is linearly configured by the upper surface of the flat transport guide 11. Accordingly, the recording paper P separated from the transfer conveyance belt 216 is smoothly guided to the pressure contact position between the heating roller 217 a and the pressure roller 217 b in the fixing device 217.
[0038]
At this time, an angle change occurs between the upper surface of the flat guide member 12 and the upper surface of the conveyance guide 11 at the other end portion on the downstream side of the conveyance guide 11, but the other end portion on the downstream side of the conveyance guide 11 is the fixing device. Since the position of the recording paper P in 217 is close to the entry position, the change in angle is small and the change in angle occurs on the upper surface of the transport guide 11 on the downstream side of the portion where the leading edge of the recording paper P abuts. The conveyance state of the paper P is not significantly impaired. As a result, the conveyance of the recording paper P can be smoothly transferred from the conveyance guide 11 to the guide member 12 in the immediate vicinity of the entry position of the recording paper P in the fixing device 217, and the recording material is guided more smoothly into the fixing device 217. be able to.
[0039]
On the other hand, even in the monochrome image forming mode in which the downstream end of the downstream frame 213b is located at the lower limit position in the transfer conveyance belt unit 213, as shown in FIG. The leading end of the recording paper P abuts on the vicinity of the intersection between the discharge direction (XX direction) of the recording paper P and the upper surface of the transport guide 11. From the contact position to the position immediately before the entry position of the recording paper P in the fixing device 217, the transport path is linearly configured by the upper surface of the flat transport guide 11. Accordingly, the recording paper P separated from the transfer conveyance belt 216 is smoothly guided to the pressure contact position between the heating roller 217 a and the pressure roller 217 b in the fixing device 217.
[0040]
Therefore, even if the vertical position of the downstream end of the downstream frame 213b of the transfer / conveyance belt unit 217 is displaced according to the image forming mode to be executed, the transfer / conveyance belt 216 is separated and the image forming unit 217 is separated. The recording paper P discharged from the recording medium P can be smoothly guided into the fixing device 217 in a stable state via the conveyance guide 11, and the recording paper P that has been heated and pressurized in the fixing device 217 is wrinkled or bent. And no jamming occurs in the fixing device 217.
[0042]
【The invention's effect】
According to the present invention, the following effects can be obtained.
[0043]
  (1)The lower surface of the other end portion of the conveyance guide pivotally supported by the downstream end portion of the image forming unit is brought into contact with the upper surface of the guide member fixed immediately near the recording material entry position in the post-processing unit. Thus, the other end portion of the conveyance guide is reliably supported by the guide member immediately in the vicinity of the recording material entering position in the post-processing portion, and the vertical position of the downstream end portion of the image forming portion is displaced according to the image forming mode. Even in this case, it is possible to prevent the other end portion of the conveyance guide from fluctuating from the position near the recording material entry position in the post-processing portion. Further, the recording material discharged from the image forming unit can be conveyed in the post-processing unit by causing the upper surface of the conveyance guide to be continuous with the upper surface of the guide member immediately near the recording material entering position in the post-processing unit. In the immediate vicinity of the entry position, it can be transferred from the conveyance guide to the guide member, and the recording material is guided more smoothly into the post-processing section.be able to.
[0044]
(2) To receive pressure from a pair of rotating members by communicating between the downstream end of the image forming unit and the closest position of the recording material in the fixing unit by a single flat plate-shaped conveyance guide. In contrast to the fixing unit, where the recording material is likely to be wrinkled or bent due to a change in the conveyance state after being discharged from the image forming unit, it is always stable regardless of the vertical position of the downstream end of the image forming unit. Recording material can be entered.
[Brief description of the drawings]
FIG. 1 is a schematic diagram showing the configuration of a digital color copying machine that is an image forming apparatus to which a conveyance guide according to an embodiment of the present invention is applied.
FIG. 2 is a diagram showing a configuration and operation of a main part of an image forming unit in a color image forming mode in the digital color copying machine.
FIG. 3 is a diagram illustrating a configuration and operation of a main part of an image forming unit in a monochrome image forming mode in the digital color copying machine.
FIG. 4 is a diagram illustrating a configuration and an operation in a color image forming mode of a conveyance guide according to the embodiment of the present invention.
FIG. 5 is a diagram illustrating the configuration and operation of a conveyance guide according to an embodiment of the present invention in a monochrome image formation mode.
FIG. 6 is a diagram illustrating the configuration and operation of a conventional conveyance guide in a color image forming mode.
FIG. 7 is a diagram illustrating the configuration and operation of a conventional conveyance guide in a monochrome image forming mode.
[Explanation of symbols]
1-Digital color copier (image forming device)
11-Transport guide
12-Guide member
210-Image forming unit
217-Fixing device (post-processing section)
P-recording paper (recording material)

Claims (3)

A plate-shaped conveyance guide supported in a swingable manner with one end portion as a fulcrum in the vicinity of the downstream end portion of the image forming portion in which the downstream end portion in the conveyance direction of the recording material is displaced in the vertical direction according to the image forming mode. In the conveyance guide of the image forming apparatus that contacts the bottom surface of the recording material that has passed through the image forming unit and guides the recording material to the post-processing unit,
A guide member fixed near the recording material entry position in the post-processing section and facing the lower surface of the recording material;
By lower surface of the other end portion abuts always on the upper surface of the guide member, the image forming, characterized in that the other end is supported from below side in the last entry position of the recording material in the post-processing unit Equipment transport guide. The conveyance guide for an image forming apparatus according to claim 1, wherein the post-processing unit is a fixing unit in which a recording material enters a press-contact portion between a pair of rotating members. The conveyance guide of the image forming apparatus according to claim 1 , wherein the contact position of the lower surface of the other end portion on the upper surface of the guide member changes according to the displacement of the image forming unit.

Images