JP2006035514A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus which prevents irregularities in image from occurring in a loop forming unit for matching carrying speeds different from each other in a printing processing part and a heating processing part. <P>SOLUTION: The loop forming unit 1C is provided between the printing processing part 1A with a printing part 20 for forming an image by ejecting an ink droplet to a sheet-like recording medium M, and a fixing processing part 1D for applying fixing processing to the printed recording medium by heating. The loop forming unit 1C is provided with: a first carrying part 50a for accumulating the recording medium in a looped shape between a first carrying roller 41 and a second carrying roller 51; and a first loop guide part 53 can perform attitude switching between a guide attitude for guiding a starting end of the recording medium from the first carrying roller to the second carrying roller, and a receding attitude for accumulating the recording medium in the looped shape between the first carrying roller and the second carrying roller. A media guide part 54, which makes the recording medium fall downward after receiving a rear end of the recording medium falling along the first loop guide part, is provided below the first loop guide part. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention provides a print processing unit having a printing unit that forms an image by ejecting ink droplets onto a sheet-like recording medium, a fixing processing unit that heats and fixes the recording medium subjected to the printing process, and the printing process A loop forming unit that is provided between the print processing unit and the fixing processing unit and that conveys the recording medium in a loop shape while absorbing a difference in processing speed of the recording medium in the printing processing unit and the fixing processing unit. The present invention relates to an image forming apparatus that is provided.

  The image forming apparatus described above forms an image with sublimation ink droplets while pulling out a long recording medium mounted in a roll shape in the print processing unit, and fixes the image forming recording medium to the fixing processing unit. As shown in FIG. 7A, the recording medium discharged after being subjected to the printing process by the upstream printing processing unit 1A is heated by the downstream heating processing unit 1D. At this time, since the conveyance speed of the recording medium M differs depending on the processing process, the loop forming unit 1C is provided to perform the continuous processing by matching the conveyance speeds in both the processing units 1A and 1D.

The loop forming unit 1C includes a first transport unit 50a that accumulates the recording medium M discharged from the print processing unit 1A in a loop between the first transport roller 41 and the second transport roller 51, and the recording medium M. A guide posture (indicated by a one-dot chain line in the figure) for guiding the starting end of the recording medium from the first conveying roller 41 to the second conveying roller 51, and the recording medium M between the first conveying roller 41 and the second conveying roller 51. Is provided with a first loop guide portion 53 that is switchable between a retracted posture (indicated by a solid line in the figure) and accumulated in a loop shape, and the recording medium M is formed by the first loop guide portion 53 in the guiding posture. When the first loop guide portion 53 is switched to the retracted posture after the start end of the first loop is guided from the first transport roller 41 to the second transport roller 51 and the start end reaches the second transport roller 51, the first and second transport Low Recording medium M to the lower space of 41 and 51 are configured to be accumulated in a loop.
JP 2003-326789 A

  However, in the loop forming unit 1C described above, when the rear end of the recording medium M passes through the first conveying roller 41 and falls into the loop forming space, the recording medium wound in the roll shape is wound around the recording medium. As shown in FIGS. 7 (a) and 7 (b), since the winding rod curled in the direction is attached, the rear end falls while contacting the guide surface of the first loop guide portion 53 in the retracted position. . At this time, when the first loop guide portion 53 in the retracted posture is slightly tilted to the left or right due to being attached in a cantilever manner, the rear end of the recording medium M is moved from the horizontal posture due to the influence of the tilt. As shown in FIG. 7C, the end of the recording medium comes into contact with the side plate that partitions the space for loop formation and deforms, or is sandwiched between the side plate and the frame. When the paper is conveyed downstream, an unnecessary load is applied and the recording medium M may be damaged.

  In particular, when the recording medium M is wound in a roll shape, the rear end of the recording medium M discharged from the print processing unit is easily curled downward by the curl and while sliding on the first loop guide unit 53. The tendency to fall was remarkable, and the above-mentioned problem was an important improvement point.

  In addition, the ink on each surface is transferred to the printed surface that is rubbed by the impact when the trailing edge of the recording medium drops onto the top of the previously accumulated recording medium, distorting the image and losing commercial value. There was a risk of getting it.

  In view of the above-described conventional disadvantages, the present invention is to provide an image forming apparatus in which image disturbance does not occur in a loop forming unit that matches different conveyance speeds in a print processing unit and a heat processing unit.

  In order to achieve the above object, a first characteristic configuration of an image forming apparatus according to the present invention is an image formed by ejecting ink droplets onto a sheet-like recording medium as described in claim 1 of the document of the claims. A print processing unit having a print unit for forming a print processing unit, a fixing processing unit for heating and fixing the recording medium subjected to the printing process, and a loop between the printing processing unit and the fixing processing unit. An image forming apparatus comprising a loop forming unit that conveys while absorbing a processing speed difference of the recording medium in the print processing unit and the fixing processing unit by accumulating in a form, and the loop forming unit A first conveyance unit that accumulates the recording medium discharged from the print processing unit in a loop between the first conveyance roller and the second conveyance roller; There is provided a first loop guide portion that can switch between a guiding posture for guiding the second conveying roller and a retracting posture for accumulating the recording medium in a loop between the first conveying roller and the second conveying roller. At the same time, a media guide portion is provided below the first loop guide portion, which receives the rear end of the recording medium falling along the first loop guide portion and then drops it downward.

  According to the above-described configuration, the rear end side of the recording medium that falls while coming into contact with the first loop guide portion is temporarily received by the media guide portion located below the first loop guide portion, and then falls downward. Therefore, the posture is corrected when it is received by the media guide part, and the abnormal situation that the end part contacts the side plate that partitions the space for loop formation or is sandwiched between the side plate and the frame is avoided. In addition, since the impact force due to the collision with the recording medium on which the loop has already been formed is reduced when the trailing edge of the recording medium falls, the situation where the print surfaces rub against each other strongly is solved, This eliminates the problem of ink transfer noise.

  As described in claim 2, the second characteristic configuration is that, in addition to the first characteristic configuration described above, the media guide portion is provided in a horizontal posture along the width direction of the recording medium. is there.

  According to the above configuration, since the media guide portion is provided in a horizontal posture along the width direction of the recording medium, when the rear end portion of the recording medium M falls, it is received by the media guide portion. Therefore, it is possible to avoid an abnormal situation in which the end portion is in contact with the side plate that partitions the space for loop formation or is sandwiched between the side plate and the frame.

  In the third characteristic configuration, as described in claim 3, in addition to the first or second characteristic configuration described above, the media guide portion receives the rear end of the recording medium and then drops downward. The configuration is such that the posture can be switched between the action posture and the retracted posture separated from the lower side of the first loop guide portion toward the print processing portion.

  According to the above-described configuration, when trouble such as the recording medium M being jammed in the loop forming unit occurs, the operator switches the position of the media guide unit from the operating position to the retracted position so that the removal work can be performed. Space can be secured, and quick removal is possible.

  As described above, according to the present invention, it is possible to provide an image forming apparatus in which image disturbance does not occur in a loop forming unit that matches different conveyance speeds in a print processing unit and a heat processing unit.

  Embodiments of an image forming apparatus according to the present invention will be described below. As shown in FIGS. 1 and 3, the image forming apparatus 1 includes a print processing unit 1A that forms an image by ejecting ink droplets onto a sheet-like recording medium M, and the recording discharged from the print processing unit 1A. The drying processing unit 1B for receiving and drying the medium M, the loop forming unit 1C for storing the recording medium M dried by the drying processing unit 1B in a loop shape, and the recording stored by the loop forming unit 1C A fixing processing unit 1D that heats and fixes the medium M is provided.

  As shown in FIG. 2, the recording medium M used in the image forming apparatus includes a sheet-like base material M1 having a predetermined rigidity made of a synthetic resin material such as polyethylene terephthalate (PET), and an upper surface thereof. The protective layer M2 is made of a material having high weather resistance such as a fluororesin that is integrally provided, and the ink receiving layer M3 that is adhered to the upper surface of the protective layer M2 through an adhesive in a peelable manner.

  Images such as photographic images, illustrations, and characters are printed on the surface of the ink receiving layer M3 by water-based ink containing a sublimation dye in the print processing unit 1A, dried in the drying processing unit 1B, and then fixed in the fixing processing unit 1D. By the heat treatment, the sublimable dye sublimates and is fixed by penetrating into the protective layer M2. Thereafter, the ink receiving layer M3 is peeled off to obtain a sheet on which a very glossy and vivid image is recorded. The recording medium M is used for signboards, trains, buses, etc. installed outdoors. It is preferably used for an image recording medium for advertisement and the like attached to the vehicle body.

  As shown in FIGS. 1 and 3, the print processing unit 1 </ b> A applies ink droplets to the print conveying unit 10 that conveys the sheet-like recording medium M and the recording medium M that is conveyed by the print conveying unit 10. The printing unit 20 is configured to be ejected to form an image, and is printed out on the recording medium M based on print data input via the communication control line L1 connected to the image processing system 100.

  The print transport unit 10 pulls out the recording medium M from a recording medium storage unit 10a in which the long recording medium M wound in a roll shape is rotatably supported by a pair of rollers 11, and is in the sub-scanning direction. And a feeding roller 12 driven by a stepping motor that conveys the recording medium, and a pressing roller 13, and a suction unit 15 that prevents the recording medium M conveyed by the feeding unit from floating on the platen 14. Is done. That is, the recording medium M is nipped and conveyed by the driving roller 12 and the pressing roller 13.

  The printing unit 20 ejects six sublimation inks of “black”, “cyan”, “magenta”, “yellow”, “light cyan”, and “light magenta” to form a color image. A head 21, guide rods 22 and 22 for supporting the print head 21 so as to be reciprocally movable in the width direction of the recording medium M, a stepping motor and a timing belt for reciprocatingly driving the print head 21 along the guide rod 22. A drive mechanism (not shown) provided, etc. is configured to reciprocate in the main scanning direction perpendicular to the sub-scanning direction with respect to the recording medium M conveyed in the sub-scanning direction by the print conveying unit 10. While forming an image.

  The print head 21 is attached with an ink cartridge for supplying ink to an ejection mechanism (not shown) composed of a piezo element and the like, and is lowered as necessary to cut the recording medium M along the main scanning direction. A cutter 24 is provided.

  The drying processing unit 1B includes a drying unit 30 that receives and dries the recording medium M discharged from the printing processing unit 1A, and a receiving conveyance unit 40 that conveys the recording medium M dried by the drying unit 30. It is prepared for.

  As shown in FIGS. 3 and 4, the drying unit 30 sucks hot air from the heater 31 disposed at the lower back of the apparatus and the guide passage 32 to the ink application surface of the recording medium M. The receiving and conveying unit 40 is configured to receive and convey the recording medium M sent out by the driving roller 12 of the print processing unit 1A on the downstream side of the drying unit 30. A conveyance roller 41 is used.

  The loop forming unit 1C is stored in the first accumulating unit 50 and the first accumulating unit 50 that accommodates the recording medium M from the drying processing unit 1B in a loop shape without applying unnecessary tension. In order to receive the recording medium M and supply it to the subsequent fixing processing unit 1D without applying unnecessary tension, the second storage unit 70 also stores the same in a loop shape, and includes the printing processing unit 1A and the drying processing. It is configured to absorb the difference in processing speed between the unit 1B and the fixing processing unit 1D, that is, the conveyance speed of the recording medium M.

  The first accumulation unit 50 includes a first conveyance unit 50a that accumulates the recording medium M discharged from the print processing unit 1A in a loop shape, and a first loop guide unit 53 provided in the first conveyance unit 50a. And a media guide portion 54 provided below the first loop guide portion 53.

  The first transport unit 50a receives and transports the recording medium M discharged from the print processing unit 1A, and the recording medium M transported by the first transport roller 41 on the downstream side. The recording medium M accumulates in a loop between the first conveyance roller 41 and the second conveyance roller 51. Is done. Accordingly, the receiving roller 41 is also used as the receiving and conveying unit 40.

  The first loop guide portion 53 is cantilevered and supported on the front side, and guides the leading end of the recording medium M from the first conveying roller 41 to the second conveying roller 51; and the recording medium M The posture is switchable between a retracted posture in which the first transport roller 41 and the second transport roller 51 are accumulated in a loop shape. In other words, the first loop guide portion 53 acts as a guide plate for the recording medium M by driving the sector gear mechanism connected to the swing shaft fixed in a cantilever manner to rotate forward and backward by the stepping motor. The posture is switchable between a guide posture and a retracted posture that swings and opens to form a loop.

  The first loop control unit is transported by the first transport roller 41 and guided by the first loop guide unit 53 after a predetermined time after the leading end of the recording medium M is detected by the sensor S2. When it is determined that the belt is sandwiched between the two transport rollers 51, the second transport roller 51 is stopped and the lower end of the first loop guide portion 53 is swung to the right to be carried into the lower space. Control is performed so that the recording medium M is accumulated in a loop between the first conveyance roller 41 and the second conveyance roller 51.

  As shown in FIGS. 3 to 5, the media guide portion 54 includes a pair of support plates 54 b that are pivotably attached to the front and back sides of the first storage portion 50, and the support plates. 54b, that is, a receiving portion 54a attached in a horizontal posture along the width direction of the recording medium M, and is discharged from the print processing portion 1A and passes through the first conveying roller 41. The rear end portion of the recording medium M that falls later is received by the receiving portion 54a.

  The second accumulating unit 70 receives the recording medium M from the first accumulating unit 50 and conveys it to the fixing processing unit 1D, and a second conveying unit 70a provided in the second conveying unit 70a. Loop guides 72 and 73 are provided.

  The second transport unit 70a includes a third transport roller 52, a fourth transport roller 53, and a second loop control unit that controls loop formation, and the third transport roller 52 and the fourth transport roller. 53, the recording medium M is accumulated in a loop. The second transport roller 51 and the third transport roller 52 may be configured by the same transport roller without being configured separately.

  The second loop control unit is conveyed by the second conveyance roller 51 and the third conveyance roller 52, and the leading end of the recording medium M guided by the second loop guide units 72 and 73 is detected by a sensor S3. If it is determined that the paper has been clamped by the fourth transport roller 71 after a predetermined time, the fourth transport roller 71 is stopped and the lower end of the left guide plate 73 of the second loop guide portions 72 and 73 is stopped. Is moved to the left and the recording medium M conveyed by the second conveying roller 51 and the third conveying roller 52 is moved between the fourth conveying roller 71 and the third conveying roller 52. Control to accumulate in a loop. The recording medium M accumulated in the second accumulation unit 70 is then conveyed to the fixing processing unit 1D by the fourth conveyance roller 71 driven at a predetermined timing.

  The guide plate 73 on the left side of the second loop guide portion has a guide posture that acts as a guide plate for the recording medium M by driving a sector gear mechanism connected to the swing shaft forward and backward with a stepping motor. It is configured to be switchable to a retracted posture that swings and opens to form a loop.

  When the recording medium M discharged from the print processing unit 1A is short, the recording medium M is transported so as to be accommodated in the second accumulation unit 70 after being accommodated in the first accumulation unit 50, and further to the second accumulation unit 70. It is conveyed from the accumulating unit 70 to the fixing processing unit 1D. Then, after the recording medium M is conveyed from the first accumulation unit 50 to the second accumulation unit 70, the new recording medium M from the print processing unit 1A is conveyed to the first accumulation unit 50. The printing medium M is configured such that printing, drying, and fixing processes are continuously performed.

  When the recording medium M ejected from the print processing unit 1A is long, one recording medium M is stored in both the first storage unit 50 and the second storage unit 70, Adverse effects caused by accumulation only in the storage unit, that is, printing of the recording mediums that the recording medium M on the rear end side overlaps on the front end side of the recording medium M that has already been accumulated, and are joined to each other by its weight. It is configured so that there is no inconvenience that ink transfer occurs between the surfaces.

  As shown in FIG. 3, the fixing processing unit 1D includes a metal outer casing 80 and a heating casing 81 disposed in the outer casing 80. The heating casing 81 is a heat insulating material. The heating medium 81 is substantially closed from the upper, lower, left, and right front and rear surfaces (not shown), and the inside of the heating casing 81 is configured as a heating area 82 of the recording medium M that is conveyed in the horizontal direction.

  The heating area 82 is provided with a heating and conveying mechanism 83 for conveying the recording medium M supplied from the loop forming unit 1C. The heating and conveying mechanism 83 receives and conveys the recording medium M in order from the upstream side in the conveying direction. It comprises a roller 84, a first roller group 85, a second roller group 86 disposed near the center of the fixing processing section 1D, and a third roller group 87 disposed on the most downstream side, and a stepping motor and a transmission mechanism (not shown). Thus, any roller is driven to rotate at a peripheral speed synchronized with each other. Further, the peripheral surface of each roller is made of a material such as silicon rubber having a high friction coefficient and high heat resistance.

  In the heating area 82, there are a plurality of rod-shaped heating elements 88 disposed upstream of the center of the heating area 82 above the conveyance surface of the recording medium M, and above the conveyance surface of the recording medium M. A first heating mechanism 91 that includes an agitating fan 89 disposed downstream of the center of the heating region 82 and heats the internal air to a predetermined temperature (for example, around 180 degrees), and the first roller group 85 and a second heating panel 93 disposed between the second roller group 86 and the third roller group 87, and a first heating panel 92 disposed between the second roller group 86 and the second roller group 87. The recording medium M is provided with a second heating mechanism 94 that heats from the back surface of the recording medium M, and the recording medium M heated by the second heating mechanism 94 is formed of a polyethylene film provided outside the apparatus after the fixing process is completed. Slope-shaped discharge shoe It is discharged onto 95.

  As shown in FIG. 1, the image processing system 100 includes a general-purpose computer 101, a monitor device 102, a keyboard 103 and a mouse 104, a film scanner 105 that photoelectrically converts image information of a developed photographic film F, and the like. The computer 101 has a built-in media drive unit 101a for reading image data recorded on various electronic data recording media such as a CD-R, MO, compact flash card, and floppy disk.

  Photo image data read by the film scanner 105, image data read from an electronic data recording medium, and the like are edited by the image processing system 100, and the above-described image forming apparatus is used as print data via the communication control line L1. To start a predetermined image forming operation.

  As shown in FIG. 6, the control block configuration of the image forming apparatus described above includes a printing process control unit 200 that controls the printing process by the printing process unit 1A and the recording medium M by the drying process unit 1B. A drying processing control unit 300 that performs the above-described drying processing, a loop control unit 400 that performs conveyance and accumulation control of the recording medium M by the loop forming unit 1C, and a fixing that controls the fixing processing by the fixing processing unit 1D. It is comprised with the process control part 500. FIG.

  The print processing control unit 200 conveys the microcomputer 201, each memory of the ROM 202 and RAM 203, the communication interface circuit 204 with the computer 101 of the image processing system 100, and the recording medium M in the sub-scanning direction. A drive roller 12, a suction fan provided in the suction unit 15, a drive mechanism for reciprocatingly driving the print head 21 in the main scanning direction, a driver circuit 205 for the print head 21 and the like for discharging ink droplets, and the recording medium M The signal input buffer circuit 206 and the like for the remaining amount, the transport position, the remaining amount of the ink cartridge, and the like are provided, and each load is driven and controlled based on a predetermined sequence program and input signals stored in the ROM 202.

  The loop control unit 400 includes a microcomputer 401, memories of ROM 402 and RAM 403, a communication interface circuit 404 with the computer 101 of the image processing system 100, the first transport roller 41, and the second transport roller 51. A driver circuit 405 for the third transport roller 52, the fourth transport roller 71, the first loop guide portion 53, the second loop guide portions 72, 73, and the like, and a plurality of transport positions for detecting the recording medium M. The first storage unit 50 controls the storage of the above-described recording medium M by controlling each load based on a predetermined sequence program stored in the ROM 402 and an input signal. The second storage unit 70 stores the first loop control unit and the recording medium M. To function as the second loop controller.

  The drying processing control unit 300 and the fixing processing control unit 500 are configured to include driver circuits 301 and 501 for heaters, fans, conveyance rollers, and the like, and signal input buffer circuits 302 and 502 such as temperature sensors, and the loop control unit. The microcomputer 401 is driven and controlled.

  Hereinafter, the media guide portion 54 will be described in detail. When the image forming operation is started and the trailing end of the recording medium M accumulated in the first accumulation unit 50 drops after passing through the first conveying roller 41, the recording medium M wound in a roll shape 5 has a curl that curls in the winding direction, and as shown in FIG. 5 (a), the rear end falls while contacting the guide surface of the first loop guide portion 53 in the retracted position. . At this time, the first loop guide portion 53 in the retracted posture is slightly tilted to the left and right due to cantilever attachment, and the rear end of the recording medium M is tilted from the horizontal posture due to the influence of the tilt. Even when the recording medium M has been changed to the recording medium M that has fallen downward from the first loop guide portion 53, the rear end portion of the recording medium M is the media guide portion 54 as shown in FIGS. The inclined posture is corrected by being received by the receiving portion 54a, and an abnormal situation such as an end portion coming into contact with a side plate partitioning a space for loop formation or being sandwiched between the side plate and the frame is avoided.

  Further, when the trailing edge of the recording medium M falls, it is received by the receiving portion 54a of the media guide portion 54, so that the dropping speed to the recording medium M on which the loop has already been formed is reduced, and the impact is reduced. This eliminates the situation in which the printing surfaces are rubbed strongly by force, and the problem of the occurrence of ink transfer noise is solved.

  As shown in FIGS. 3 and 4, the media guide portion 54 is located immediately below the first loop guide portion 53, and once the rear end portion of the recording medium M is received by the receiving portion 54a, the media guide portion 54 is lowered. The posture can be switched between an action posture of dropping to the print processing portion and a retracting posture in which the receiving portion 54a is separated from the lower side of the first loop guide portion 53 toward the print processing portion by the swinging of the support plate 54b. Has been.

  For example, when a trouble such as the recording medium M being transported being jammed by the second transport roller 51 occurs, the operator manually swings the receiving portion 54a of the media guide portion 54 in the working posture to the retracted posture. By performing the dynamic operation, a space necessary for the operation for removing the jammed recording medium M can be secured, and the removal operation can proceed.

  That is, when the media guide portion 54 is in the working posture, an operator is obstructed from performing maintenance work such as removal of clogging of the recording medium M. Therefore, the working space is secured by switching to the retracted posture. This makes it possible to speed up the work.

  Another embodiment will be described below. In the above-described embodiment, the media guide portion 54 includes the receiving portion 54a and two support plates 54b attached to both ends of the receiving portion 54a, and is retracted by swinging the support plate 54b. However, the posture switching mechanism between the working posture and the retracted posture of the media guide portion 54 is not limited to this, and the receiving portion 54a is horizontally moved at the back side fulcrum. It may be attached so as to swing and may be attached so that the receiving part 54a slides horizontally in the horizontal direction.

1 is an external perspective view of an image forming apparatus according to the present invention. Illustration of recording medium Side sectional view showing schematic configuration of image forming apparatus Side sectional view showing schematic configuration of loop forming unit The recording medium conveyance operation in the loop forming unit is shown, (a) is a front view, (b) is a front view, and (c) is a side view of (b) seen from the right side. Control block diagram of image forming apparatus FIG. 4A illustrates a recording medium conveyance operation in a conventional loop forming unit, where FIG. 5A is a front view, FIG. 5B is a front view, and FIG. 5C is a side view of FIG.

Explanation of symbols

1: Image forming apparatus 1A: Print processing section 1C: Loop forming unit 1D: Fixing processing section 20: Printing section 41: First transport roller 51: Second transport roller 50a: First transport section 53: First loop guide section 54 : Media guide part 54a: Receiving part 54b: Support plate M: Recording medium

Claims (3)

A printing processing unit having a printing unit that forms an image by ejecting ink droplets onto a sheet-like recording medium, a fixing processing unit that heats and fixes the recording medium subjected to the printing process, the printing processing unit, and the fixing A loop forming unit provided between the processing units and configured to store the recording medium in a loop shape to convey a difference in processing speed of the recording medium between the print processing unit and the fixing processing unit. An image forming apparatus,
In the loop forming unit, a first transport unit that accumulates the recording medium discharged from the print processing unit in a loop shape between a first transport roller and a second transport roller, and a start end of the recording medium is the first end. A first loop that can be switched between a guiding posture for guiding from one conveying roller to a second conveying roller and a retracting posture in which the recording medium is accumulated in a loop between the first conveying roller and the second conveying roller. An image forming unit provided with a guide unit and a media guide unit provided below the first loop guide unit and receiving a rear end of the recording medium falling along the first loop guide unit and then dropping down. apparatus.   The image forming apparatus according to claim 1, wherein the media guide unit is provided in a horizontal posture along a width direction of the recording medium.   The media guide portion is switchable between an action posture in which the media guide portion receives the rear end of the recording medium and then drops downward, and a retreat posture in which the media guide portion is separated from the lower side of the first loop guide portion toward the print processing portion. The image forming apparatus according to claim 1, wherein the image forming apparatus is configured as follows.

Images