JP2005272120A - Image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To ensure the rigidity of an apparatus main body and a drawer frame and improve the jam handling performance in an image forming apparatus provided with an automatic sheet feeder.
SOLUTION: Under the image forming means 90, there are paper feeding devices 10 and 13 for feeding sheets to the image forming means 90, and a double-sided conveyance path 81 located above the automatic paper feeding device. In addition, at least two or more of the paper feeding devices 10 and 13 are arranged side by side, and a double-sided conveyance path 81 has a merging portion where the conveyance path 21 from the paper feeding device 13 located on the upstream side joins, The double-sided conveyance path on the downstream side of the joining portion in the path 81 is fixed to the image forming apparatus main body, and the double-sided conveyance path on the upstream side of the joining portion is configured to be drawable to the image forming apparatus main body.
[Selection] Figure 2

Description

  The present invention relates to an image forming apparatus that forms an image on a sheet material.

  In an image forming apparatus, sheet materials of various sizes and materials are generally fed by a sheet feeding device, sent to an image forming unit, and after an image is formed, an unfixed image is fixed and discharged.

  In recent years, in an image forming apparatus, in order to reduce the installation space, it is desired to reduce the space of the apparatus. On the other hand, the type of sheet material to be conveyed is increasing year by year and requires a large number of paper feed stages, and a feeding device capable of feeding a large amount of paper is provided to eliminate the troublesomeness of sheet replenishment. Is also desired. In response to these demands, as shown in FIG. 10, a paper deck capable of accommodating and feeding a large-capacity sheet is disposed on the side surface of the apparatus body, and the sheet is supplied from the paper deck. (For example, refer to Patent Document 1).

  However, in this configuration, the space of the apparatus increases by the amount that the paper deck protrudes laterally from the side of the apparatus. In addition, since the sheet is replenished to the paper deck from the side of the apparatus, a work space for that is required, and the substantial installation space increases.

In order to solve this problem, as shown in FIG. 11, in an image forming apparatus provided with an automatic sheet feeder for supplying sheets to the lower side of the image forming unit, the automatic sheet feeder stacks sheets. A plurality of sheet supporting means for supporting are arranged side by side in the lateral direction, and a feeding means is provided corresponding to each sheet supporting means in order to send out the sheet supported by the sheet supporting means (for example, patent document) 2).
Japanese Patent Registration No. 320502 Japanese Patent Registration No. 2625057

  In this way, in the feeding means 10 and 13 in which the sheet feeding devices are arranged side by side, when the sheet material S stops across the sheet feeding unit 14 and the double-sided conveyance unit 17 at the merging unit 16, the jam processing is performed. It was supposed to reduce operability.

  In order to solve this problem, the column 18 for holding the guide and holding the paper feed unit is provided in accordance with the guide shape of the merging portion 16, but the rigid body is weak because the guide shape is given priority.

  A sheet feeding unit 14 having a roller for feeding the sheet S to the merge unit 16 is attached to a support unit 15 supported by a left column and a rear plate of the apparatus main body. Since the portion of the confluence guide is cut, it is weakened in a cantilevered state.

  For this reason, the paper feeding pressure may vary due to the low rigidity at the time of paper feeding, resulting in poor paper feeding (FIG. 12).

  Due to recent colorization, the image forming means 90 (laser scanner, photosensitive drum, developing device, charging device, cleaning device) and the transfer units 43 and 44, the transfer belt 40, the registration device 30 and both sides of the image forming means 90 are provided below. An increasing number of units are provided with a transport unit 17 and the like. In order to perform jam processing and maintenance, a structure in which a drawer frame 31 surrounded by an alternate long and short dash line can be pulled out by a slide rail or the like is increasing. Rigidity that can withstand the pressure and the weight of the apparatus is required, and the above-mentioned column configuration cannot ensure rigidity, the drawer frame 31 is distorted by the load of the unit, the accuracy of the registration apparatus 30 decreases, the transfer 43, The problem was that the pressure of 44 varied.

  The present invention includes an automatic sheet feeder for supplying sheets to the image forming unit on a lower side of the image forming unit, and a double-sided conveyance unit positioned on the upper side of the automatic sheet feeder. In the image forming apparatus, wherein at least two or more paper devices are arranged side by side, and the double-sided conveyance unit includes a merging unit where a conveyance path from an automatic paper feeder located upstream is merged, the merging in the double-sided conveyance unit The double-sided conveyance unit downstream of the image forming unit is fixed to the image forming apparatus main body, and the double-sided conveyance unit upstream of the merging unit is configured to be drawable with respect to the image forming apparatus main body.

  By using the present invention, it is possible to supply an image forming apparatus that ensures the rigidity of the apparatus main body and the drawer frame and at the same time sacrifices the jam handling performance.

  Hereinafter, the present invention will be described more specifically with reference to embodiments. In addition, although these embodiment is an example of the best embodiment in this invention, this invention is not limited by these embodiment.

(Embodiment 1)
An embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a schematic cross-sectional view of an image forming apparatus to which the present invention is applied. Reference numeral 1 denotes a printer body. Above the printer body 1, engine portions Y, M, C, and BK for forming primary images of a total of four colors of yellow, magenta, cyan, and black are arranged. Print data transmitted from an external device such as a personal computer is received by a controller that controls the printer body 1 and is output as write image data to the laser scanners 93, 96, 97, and 98 for each color.

  The laser scanner emits a laser beam onto the photosensitive drum 91 and draws an optical image according to the written image data. Reference numeral 94 denotes a folding mirror that folds the laser beam toward the photosensitive drum 91. The images on the transfer belt are matched by adjusting the writing timing of each color laser scanner.

  The primary image forming unit of each color includes a photosensitive drum 91, a charger (not shown) for uniformly charging the surface of the photosensitive drum 91, and the laser scanner 93 on the surface of the photosensitive drum 91 charged by the charger. A developing device 92 for developing an electrostatic latent image created by drawing an optical image into a toner image to be transferred to the intermediate transfer belt 40, and a toner image developed on the surface of the photosensitive drum 91 as an intermediate. A primary transfer roller 45 for transferring to the transfer belt 91 and a cleaner 95 for removing the toner remaining on the photosensitive drum 91 after transferring the toner image. The toner image primarily transferred to the intermediate transfer belt 40 is retransferred onto the sheet by the secondary transfer roller 44. The toner remaining without being transferred by the secondary transfer roller 44 is collected by the cleaner 46. Reference numeral 41 denotes a transfer belt driving roller, 42 denotes a transfer belt tension roller, which applies tension to the transfer belt 40 and keeps the belt tensioned, and 43 is a primary transfer counter roller.

  The sheet feeding unit is located at the uppermost stream of sheet conveyance, and in the printer of the present embodiment, two stages are arranged in the lower part of the apparatus (10, 13). The paper lifter plate 11 pushes the stacked sheets S up to the rollers of the paper feed units 12 and 14. The sheet feeding units 12 and 14 employ a configuration in which the uppermost sheet is picked up by a roller and sent downstream, but this can also employ air feeding in which the sheet is sucked and sent by air. The sheet S fed from the sheet feeding units 12 and 14 is conveyed downstream through the vertical conveyance path 20. At the most downstream position of the vertical conveyance path 20, there is a registration roller device 30, where final skew correction of the sheet and image writing and sheet conveyance timing in the image forming unit are performed.

  A fixing device 50 for fixing the toner image on the sheet S as a permanent image is provided on the downstream side of the image forming unit.

  A flapper (not shown) capable of switching the conveyance path after passing through the fixing device 50 is provided, and a double-sided conveyance path can be selected in accordance with a request signal from the controller. A sheet reversing unit 70 also serving as an entrance to a duplex conveyance path 80 for duplex printing and a discharge roller 60 for discharging the sheet S on which an image is fixed from the printer main body 1 are provided. A paper discharge tray 61 for receiving the sheet S discharged by the discharge roller is configured.

  An embodiment of the present invention will be described with reference to FIG.

  The sheet feeders 10 and 13 are placed side by side below the image forming means.

  A duplex unit frame 32 that can be pulled out from the apparatus main body is provided on the sheet feeding apparatuses 10 and 13.

The double-sided unit frame 32 can be pulled out to the front side of the apparatus main body by a slide rail 33,
The double-sided conveyance path 81, the registration apparatus 30, and the transfer unit 44 upstream from the merging unit path 21 of the sheet feeding device 13 are held and pulled out. The double-sided conveyance path 82 downstream from the merge path 21 remains in the apparatus main body.

  A support member 22 that receives a double-sided unit frame 32 (dashed line) is placed between the sheet feeding devices 10 and 13 that are arranged side by side, and beams 23 and 24 that hold the sheet feeding units 12 and 14 are provided on the support member 22. As a result, the holding of the sheet feeding unit 15 on the left side can be stabilized, and the rigidity of the image forming apparatus main body can be maintained by being connected without breaking the beam.

  In addition, since the double-sided unit frame 32 on which the conveying unit 51, the registration apparatus 30, and the transfer unit 44 for transferring an image to a sheet are mounted can be received by the support member 22 at a substantially central portion of the frame, Deformation and distortion of the frame can be reduced. A roller 33 for receiving the support member 22 is provided at the center of the double-sided unit frame, which allows the roller unit to be pulled out smoothly.

  The double-sided conveyance path 82 is capable of jamming a sheet by raising the upper guide of the double-sided conveyance path 82 upward.

  The drawer of the duplex unit frame 32 will be described with reference to FIGS.

  The duplex unit frame 32 can be pulled out by releasing the lock of the secondary transfer roller 44 by rotating the handle 34 in the direction of the arrow.

  The secondary transfer roller 44 is moved / pressed / released by moving the secondary transfer roller holder 47 by a cam 35 provided on a shaft extending from the handle 34.

  The two-roller holder is provided with a spring for pressing the two-roller roller.

  A lock lever member 36a is provided on the shaft of the handle 34, and the double-sided unit frame 32 cannot be pulled out from the apparatus main body by engaging with the lock member 36b in the apparatus.

  The lock is released by turning the handle 34 in the direction of the arrow.

  At this time, the guide 21 that joins both sides from the left sheet feeding unit 15 rotates the handle 34 in the direction of the arrow, and lowers the guide 21 downward to open it so that it can be jammed. It is prevented that it stops across.

  By rotating the guide release lever 37a provided on the shaft extending from the handle 34, the guide release gear 37b provided on the apparatus main body is rotated, and the gear portion 21c provided on the lower junction path guide 21b is moved. The merge path 21 can be opened.

  FIG. 5 is a view showing a state in which the duplex unit frame 32 is pulled out. Jam processing is performed by hearing the double-sided unit frame 32 and opening the double-sided conveyance path 81 of the double-sided unit frame 32 downward as indicated by an arrow.

(Embodiment 2)
In the first embodiment, the system using the intermediate transfer belt has been described. However, as shown in FIGS. 6 and 7, the same effect can be obtained by using the direct transfer belt. Those described in the first embodiment shown in the figure have the same numbers and will not be described.

  Reference numeral 2 denotes a printer main body. Engine parts Y, M, C, and BK for forming primary images of a total of four colors of yellow, magenta, cyan, and black are arranged on the upper portion of the printer main body 2. Print data transmitted from an external device such as a personal computer is received by a controller that controls the printer main body 2, and is output as write image data to the laser scanners 93, 96, 97, and 98 for each color.

  The laser scanner emits a laser beam onto the photosensitive drum 91 and draws an optical image according to the written image data. Reference numeral 94 denotes a folding mirror that folds the laser beam toward the photosensitive drum 91. The images on the transfer belt are matched by adjusting the writing timing of each color laser scanner.

  Each color image forming unit includes a photosensitive drum 91, a charger (not shown) for uniformly charging the surface of the photosensitive drum 91, and the laser scanner 93 applies light to the surface of the photosensitive drum 91 charged by the charger. A developing device 92 for developing a toner image to be transferred to the sheet S from the electrostatic latent image created by drawing the image, and a toner image developed on the surface of the photosensitive drum 91 on the transfer belt 48. A transfer roller 52 for transferring to a stuck sheet and a cleaner 95 for removing toner remaining on the photosensitive drum 91 after transferring the toner image. The toner remaining on the transfer belt 48 is collected by the cleaner 46.

  Reference numeral 49 denotes a transfer belt driving roller, and 51 denotes a transfer belt tension roller.

  The sheet feeding unit is positioned at the uppermost stream of sheet conveyance, and in the printer of the present embodiment, two stages are provided side by side at the bottom of the apparatus (10, 13). The paper lifter plate 11 pushes the stacked sheets S up to the rollers of the paper feed units 12 and 14. The sheet S fed from the sheet feeding units 12 and 14 is conveyed downstream through the vertical conveyance path 20. At the most downstream position of the vertical conveyance path 20, there is a registration roller device 38, where final skew correction of the sheet and timing adjustment of image writing and sheet conveyance in the image forming unit are performed.

  A fixing device 50 for fixing the toner image on the sheet S as a permanent image is provided on the downstream side of the image forming unit.

  A flapper (not shown) capable of switching the conveyance path after passing through the fixing device 50 is provided, and a double-sided conveyance path can be selected in accordance with a request signal from the controller. A sheet reversing unit 70 that also serves as an entrance to a duplex conveyance path 81 for duplex printing and a discharge roller 60 for discharging the sheet S on which an image is fixed from the printer main body 1 are provided. A paper discharge tray 61 for receiving the sheet S discharged by the discharge roller is configured.

  An embodiment of the present invention will be described with reference to FIG.

  The sheet feeders 10 and 13 are placed side by side below the image forming means.

  A double-sided unit frame 48 that can be pulled out from the apparatus main body is provided on the sheet feeding apparatuses 10 and 13.

The double-sided unit frame 48 can be pulled out to the near side of the apparatus body by the slide rail 33,
The double-sided conveyance path 81 and the transfer belt 49 upstream from the junction path 21 of the sheet feeding device 13 are held and pulled out. The double-sided conveyance path 82 downstream from the merge path 21 remains in the apparatus main body.

  A support member 22 that receives a double-sided unit frame 48 (dashed line) is placed between paper feeding devices 10 and 13 that are arranged side by side, and beams 23 and 24 that hold the paper feeding units 12 and 14 are provided on the support member 22. As a result, the left paper feeding unit 15 can be held stably, and the rigidity of the image forming apparatus main body can be maintained by being connected without breaking the beam.

  Further, since the double-sided unit frame 48 on which the transfer belt 49 is placed can be received by the support member 22 at a substantially central portion of the frame, deformation due to pressurization of the transfer portion, distortion of the frame, and the like can be reduced. A roller 33 for receiving the support member 22 is provided at the center of the double-sided unit frame, which allows the roller unit to be pulled out smoothly.

  The double-sided conveyance path 82 is capable of jamming a sheet by raising the upper guide of the double-sided conveyance path 82 upward.

  The drawer of the duplex unit frame 49 will be described with reference to FIGS.

  The duplex unit frame 49 is unlocked from the pressure of the transfer belt 48 by rotating the handle 34 in the direction of the arrow, and can be pulled out.

  The transfer belt 49 is moved by the cam 101 provided on the connecting member 100 extending from the handle 34 to move the pressurizing portion 103 extending from the transfer belt frame 102 of the transfer belt 49 to be pressurized / released.

  A lock lever member 36a is provided on the shaft of the handle 34, and the double-sided unit frame 49 cannot be pulled out of the apparatus main body by engaging with the lock member 36b in the apparatus.

  The lock is released by turning the handle 34 in the direction of the arrow.

  At this time, the guide 21 that joins both sides from the left paper feeding unit 15 rotates the handle 34 in the direction of the arrow and lowers the guide 21 downward to open it so that it can be jammed. It is prevented that it stops across.

  By rotating the guide release lever 37a provided on the shaft extending from the handle 34, the guide release gear 37b provided on the apparatus main body is rotated, and the gear portion 21c provided on the lower junction path guide 21b is moved. The merge path 21 can be opened.

  FIG. 9 is a view showing a state in which the duplex unit frame 49 is pulled out.

  Jam processing is performed by hearing the double-sided unit frame 49 and opening the double-sided conveyance path 81 of the double-sided unit frame 49 downward as indicated by an arrow.

  Although these embodiments are examples of the best embodiments of the present invention, the present invention is not limited to these embodiments. For example, the same effect can be realized even when three or more automatic paper feeders are arranged under the image forming unit or when a fixing device is placed on the drawer frame.

Sectional view of the image forming apparatus of Embodiment 1 of the present invention Sectional view of the image forming apparatus of Embodiment 1 of the present invention Sectional view of the image forming apparatus of Embodiment 1 of the present invention The principal part perspective view of Embodiment 1 of this invention Sectional view of the image forming apparatus of Embodiment 1 of the present invention Sectional drawing of the image forming apparatus of Embodiment 2 of this invention Sectional drawing of the image forming apparatus of Embodiment 2 of this invention The principal part perspective view of Embodiment 2 of this invention Sectional drawing of the image forming apparatus of Embodiment 2 of this invention Diagram of an image forming apparatus for explaining a conventional example Diagram of an image forming apparatus for explaining a conventional example Diagram of an image forming apparatus for explaining a conventional example

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 2 Image forming apparatus 10, 13 Paper feeder 12, 14 Paper feed part 21 Merge path 22 Support member 33 Roller 34 Handle 32, 49 Double-sided unit frame

Claims (9)

An automatic sheet feeder for supplying sheets to the image forming unit and a double-sided conveyance unit positioned above the automatic sheet feeder are provided below the image forming unit, and the automatic sheet feeder is at least In an image forming apparatus having a merging unit that is arranged side by side in two or more, and a conveyance path from an automatic sheet feeding device located on the upstream side merges with the double-sided conveyance unit,
The double-sided conveyance unit downstream of the merging unit in the double-sided conveyance unit is fixed to the image forming apparatus main body, and the double-sided conveyance unit upstream of the merging unit is configured to be drawable with respect to the image forming apparatus main body. An image forming apparatus.   The image forming apparatus according to claim 1, wherein the double-sided conveyance unit configured to be drawable is supported by a drawable frame.   2. The pullable frame includes, in addition to the double-sided conveyance unit, a registration device for feeding a sheet to the image forming unit at a timing, and a transfer unit for transferring the image to the sheet. The image forming apparatus according to 2.   The image forming apparatus according to claim 2, wherein the pullable frame includes a transfer unit and a transfer belt for transferring an image to a sheet in addition to the double-sided conveyance unit.   5. The apparatus according to claim 2, wherein a support member that supports the pullable double-sided conveyance unit or the drawer frame is placed between the automatic paper feeders arranged side by side. 6. Image forming apparatus.   The image forming apparatus according to claim 5, wherein the support member is positioned substantially in the center of the drawer frame.   7. The image forming apparatus according to claim 1, wherein the pullable double-sided conveyance unit or the drawer frame prohibits the drawer when the guide plate of the joining unit is not in an open state. .   When the pullable duplex conveying section or drawer frame is inserted into the image forming body, it has a lock mechanism that prevents the drawer from being pulled out, and the guide of the merging section is released in conjunction with the release of the lock mechanism. The image forming apparatus according to claim 1, wherein the image forming apparatus is an image forming apparatus.   The image forming apparatus according to claim 8, wherein the transfer unit is released in conjunction with the release of the lock mechanism.

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