JP4535120B2 - Image forming apparatus - Google Patents

Description

  BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus such as a copying machine, a facsimile machine, a printer, or a multi-function machine having these functions, and more specifically, a post-processing unit that performs post-processing functions such as a stapling function, a punching function, and a sorting function. The present invention relates to an image forming apparatus including a finisher.

  As an image forming apparatus as described above, an image recording unit (for example, an electrophotographic image recording unit) installed in the middle of a paper conveyance path performs image recording from a paper supply unit, and a recorded paper discharge unit Examples include one configured to discharge and deposit paper on a (discharge tray). Recently, an image forming apparatus including the post-processing unit as described above has been put into practical use in response to a request for multi-functionality of the apparatus. In this case, in order to meet various needs, it is generally configured that the post-processing unit can be retrofitted as an optional unit to a standard specification apparatus. In this way, when the post-processing unit is retrofitted as an optional unit, the paper relay transport unit for relaying and transporting the recorded paper from the downstream end of the paper transport path in the apparatus main body to the paper introduction section of the post-processing unit May need to be installed. The sheet relay transport unit is composed of an upper guide member and a lower guide member that are combined with each other, and a plurality of transport roller pairs are installed in the combined portion. In addition, a paper jam release mechanism that releases the uniting of the upper guide member and the lower guide member is provided in order to remove paper jammed between both guide members.

Patent Documents 1 to 3 disclose examples in which a paper jam release mechanism is provided in a paper transport path for transporting paper to an image recording unit. In each of these examples, the paper jam release mechanism is configured such that one of the paired guide members is coupled to the other via a support shaft, and one of the guide members is rotated with the support shaft as a fulcrum to combine the two. Is to cancel.
Japanese Patent Laid-Open No. 3-67832 JP 7-157132 A Japanese Patent Laid-Open No. 2004-51361

  By the way, the paper relay transport unit is installed continuously to the paper transport path of the standard specification apparatus, and the space portion on the recorded paper discharge tray is used as the installation space. The image forming apparatus disclosed in Patent Documents 1 to 3 does not include a post-processing unit. When the jam release mechanism in the paper transport path disclosed in these documents is applied to the paper relay transport unit, the rear side of the apparatus main body is used as a fulcrum, and the front side of the apparatus main body is opened. However, the space on the discharge tray has a limited effective space due to the layout configuration of the apparatus. For this reason, it is not possible to secure a large opening angle on the front side when the unitary release of the upper guide member and the lower guide member, and it is difficult to insert the hand to the back side, so it is possible to smoothly remove the jammed paper. There was no problem.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide an image forming apparatus having a simple configuration and capable of easily performing a paper jam release operation in a paper relay transport unit for a post-processing unit. Yes.

An image forming apparatus according to the present invention includes an apparatus main body, an image recording unit, a post-processing unit that performs post-processing on and discharges an image-recorded sheet by the image recording unit, and a sheet conveyance path that conveys the image-recorded sheet. , An image forming apparatus including a paper relay transport unit installed between the downstream end of the paper transport path and the post-processing unit, wherein the paper relay transport unit includes a plurality of driving rollers. A fixed upper guide member, a movable lower guide member provided with a plurality of press rollers corresponding to the drive roller, and a link connecting side portions of the upper guide member and the lower guide member on the back side of the apparatus main body And a lock member that maintains the upper guide member and the lower guide member in a combined state so that each drive roller and press roller come into contact with each other, and the lock by the lock member is released. The by swinging of said link member are configured such that the lower guide member may descend, the link member, when lowering the lower guide member by releasing the lock by the lock member, an inner side of the apparatus main body It is connected between the side parts of the upper guide member and the lower guide member so as to swing vertically from the state facing toward the front side of the apparatus body, and the lower side by the swing of the link member when unlocked The lowering is performed such that the guide member protrudes toward the front side of the apparatus main body .

Te present invention smell, the front side of the front Symbol apparatus body sheet relay conveying unit is installed, fitted with closing cover, it is configured to be a locking and unlocking operation by the lock member by opening the cover Can do.

  According to the image forming apparatus of the present invention, since the sheet relay conveying unit is installed between the downstream end of the sheet conveying path and the post-processing unit, the image recording that reaches the downstream end of the sheet conveying path is performed. The finished paper is introduced into the post-processing unit through the paper relay conveyance unit. The image-recorded paper introduced into the post-processing unit is appropriately post-processed and discharged. In this paper relay conveyance unit, when a paper jam occurs, the upper guide member and the lower guide member in the combined state are opened by releasing the lock by the lock member, and the jammed paper is taken out from this open portion. Can do. When the lock is released, the lower guide member descends due to the swinging of the link member. Therefore, an open space corresponding to the length of the link member is secured on the back side, and a jam can be easily inserted into the back side. The paper can be easily taken out.

Further, since the link member is configured to swing in a vertical state from the state facing the back side of the apparatus main body to the front side of the apparatus main body, when the lock by the lock member is released, the lower guide member is The lowering is performed so as to protrude toward the front side of the apparatus main body. Therefore, depending on the state of the jam, the jammed paper may be shifted to the front side while being placed on the lower guide member, and the takeout becomes easier.

Further, when the opening / closing cover is attached to the front side of the apparatus main body on which the paper relay conveyance unit is installed, the installed paper relay conveyance unit is not visually recognized, and the appearance of the apparatus can be maintained. When a paper jam occurs, the jam paper can be easily taken out by opening the opening / closing cover and performing an unlocking operation using the lock member. In addition , the link member is configured to swing vertically from the state facing the back side of the apparatus body to the front side of the apparatus body as described above, so that the lower guide member is moved to the opening / closing cover side. The jam paper can be taken out more smoothly because it comes close.

  The best mode for carrying out the present invention will be described below with reference to the drawings. FIG. 1 is a schematic longitudinal sectional view showing an embodiment of an image forming apparatus according to the present invention, FIG. 2 is a cross-sectional plan view of a portion in which the sheet relay conveyance unit is installed, and FIG. X-ray sectional view, FIG. 4 is a view similar to FIG. 3 showing the operation state of the sheet relay transport unit at the time of jam release.

  The image forming apparatus 1 shown in FIG. 1 is a so-called multi-function machine including an electrophotographic image recording unit. That is, although it has a copy function, a facsimile function, and a printer function, it does not exclude what is embodied as a copy apparatus, a facsimile apparatus, or a printer apparatus. In the figure, the apparatus main body 10 of the image forming apparatus 1 includes a paper supply unit 2 for recording paper (paper), an electrophotographic image recording unit 3, a recording paper discharge unit 4 after image recording, and an image reading unit. 5 are stacked in this order in the height direction. The recording paper supply unit 2 includes a detachable recording paper (paper) supply cassette 21 that can store a large number of recording papers 20 in a stacked state. A separation roller 22 and a separation pad 23 that elastically contacts the peripheral surface of the separation roller 22 are installed at the front end of the recording paper supply cassette 21. Further, in the recording paper supply cassette 21, a push-up plate 24 that pushes up the stacked recording paper 20 and a compression coil spring 25 that applies upward elasticity to the push-up plate 24 are installed. Since the push-up plate 24 is always given upward elasticity by the compression coil spring 25, the front end portion of the recording paper 20 deposited on the push-up plate 24 is pressed against the peripheral surface of the separation roller 22. Therefore, when the separation roller 22 rotates, the stacked recording paper 20 is separated one by one from the uppermost layer portion by the cooperative action of the separation roller 22 and the separation pad 23, and is fed to the recording paper conveyance path 6 described later. Is paid out.

  The image recording unit 3 includes a process unit in which a plus (or minus) charger 31, an exposure unit 32, a developing device 33, a transfer roller 34, and a cleaning device 35 are arranged in this order around the photosensitive drum 30. And a fixing device 36 on the downstream side. The photosensitive drum 30, the charger 31 and the cleaning device 35 are unitized as a drum unit, and the developing device 33 is unitized as a developing device unit. Both units are individually or coupled to the apparatus main body 10. Removably mounted. Since these units are consumables, they can be inserted into and removed from the apparatus main body 10. As a mode that can be inserted / removed, in addition to the case where it can be inserted / removed in the direction perpendicular to the paper surface in FIG. Sometimes it is said. The recording paper supply cassette 21 can be inserted and removed in the direction perpendicular to the paper surface in FIG.

  A registration roller pair 7 is installed in the vicinity of the upstream side of the process unit, and the recording paper 20 separated and fed from the recording paper supply cassette 21 one by one by the action of the separation roller 22 and the separation pad 23 is It is registered by the registration roller pair 7 and introduced into the nip portion between the photosensitive drum 30 and the transfer roller 34. The surface of the photosensitive drum 30 is uniformly charged positively (or negatively charged) by the charger 31 while rotating in the direction of the arrow in FIG. 1, and an optical image based on the image information is generated by the exposure unit 32 by the photosensitive drum 30. The electrostatic latent image is formed on the surface of the photosensitive drum 30. This electrostatic latent image is formed by the difference in potential generated between the light irradiated portion and the non-irradiated portion based on the characteristics of the photoconductor on the surface of the photosensitive drum 30.

  The electrostatic latent image is successively developed by the developing device 33 to become a toner image. This toner image reaches the nip portion with the transfer roller 34 as the photosensitive drum 30 rotates. The registration roller pair 7 is rotationally driven under registration control so that the recording paper 20 is introduced into the nip portion in synchronization with the movement of the toner image on the surface of the photosensitive drum 30. The transfer roller 34 nips and conveys the recording paper 20 while being in contact with the photosensitive drum 30 and being rotationally driven in the direction indicated by the arrow (with respect to the photosensitive drum 30). During this time, the toner image on the surface of the photosensitive drum 30 is recorded. It is transferred to paper. The recording paper 20 onto which the toner image has been transferred is introduced into the fixing device 36 and fixed as a permanent image. Then, the recording paper 20 passes through a paper relay conveyance unit 13 and a post-processing unit 14 which will be described later, and is discharged with a main conveyance pass line 201 drawn. Is done. The conveyance of the series of recording papers 20 rises substantially vertically (vertically) immediately after feeding out from the recording paper supply cassette 21, and the discharge unit 4 is U in a direction of about 180 degrees from the feeding direction from the recording paper supply cassette 21. It is made along a recording paper conveyance path (hereinafter referred to as a main conveyance path) 6 that turns, and such a layout configuration makes the entire apparatus compact.

The developing device 33 is a developing device using a two-component developer, and includes a developer storage chamber for storing a developer composed of toner and a carrier inside a resin-molded casing. In the storage chamber, two agitating and conveying screws 331, a supply roller 332, and a developing roller 333 to which a bias is applied are provided. These mechanism portions 331, 332, and 333 in the storage chamber are connected to a drive transmission mechanism (not shown) in the apparatus main body 10 when the developing device 33 is attached to a predetermined part in the apparatus main body 10, and can be rotated. State. The developing roller 333 is electrically connected to a bias application power source (not shown). A toner tank 334 and a toner hopper 335 are installed at positions separated from the developer storage chamber. When the toner concentration in the developer storage chamber decreases, the toner is developed from the toner hopper 335 via a screw conveyor (pipe screw) 336. It is replenished in the medicine reservoir. The toner tank 334 is integrated with the waste toner tank 337 and is configured as a toner cartridge 330 that is detachably attached to the apparatus main body 10. The transfer residual toner removed from the surface of the photosensitive drum 30 by the cleaning device 35 is collected in a waste toner tank 337 via a screw 338.
The developing device 33 is not limited to a system using a two-component developer, but a one-component system or other systems can also be used.

  A first switching gate 8 is installed in the paper conveyance path 6 on the downstream side of the fixing device 36, and switching between the recording paper discharge side and the switchback portion side for double-sided recording is possible. In the figure, the solid line switching gate 8 is set on the switchback side, and the two-dot chain line switching gate 8 is set on the discharge side so that the recording paper 20 can be guided. A discharge roller pair 41 is installed at the downstream end of the sheet conveyance path 6. In a standard specification apparatus in which a sheet relay conveyance unit 13 as an optional unit to be described later is not installed, an image discharged by the discharge roller pair 41. The recorded paper is discharged and accumulated on the discharge tray 42. Therefore, when the optional unit is installed, the discharge tray 42 does not substantially function.

  The switchback side sheet conveyance path for duplex recording joins the reverse sheet conveyance path (hereinafter referred to as the reverse conveyance path) 9 via the second switching gate 91. The recording paper 20 guided to the switchback portion side by the first switching gate 8 pushes up the second switching gate 91 and is conveyed by the switchback roller pair 92. When the rear end of the recording paper 20 reaches the switchback roller pair 92, the switchback roller pair 92 temporarily stops with the rear end of the recording paper 20 being nipped. At this time, the front side of the recording paper 20 is held on the temporary tray 93. Thereafter, the switchback roller pair 92 is reversed, and the recording paper 20 is supplied to the reverse conveyance path 9. The reverse conveyance path 9 is configured to circulate to the main conveyance path 6 on the upstream side of the registration roller pair 7 from the attachment position of the second switching gate 91 of the main conveyance path 6. Two pairs of conveying rollers 94 and 95 are provided along the same. The recording paper 20 that has been recorded on one side and is transported along the main transport path 6 is introduced into the switchback section, and then supplied to the reverse transport path 9 by the reverse rotation of the switchback roller pair 92. The recording paper 20 supplied to the reverse conveyance path 9 is continuously conveyed along the reverse conveyance path 9 by the conveyance roller pair 94, 95, and merges with the main conveyance path 6 while drawing the reverse conveyance path line 202, and registration rollers. It reaches pair 7. Thereafter, the toner is introduced again into the nip portion between the photosensitive drum 30 and the transfer roller 34, and recording on the back surface is performed. The recording paper 20 recorded on both sides is discharged to the discharge unit 4 along the main transport path 6 as described above.

  A manual feed tray 110 is provided on the side surface of the apparatus body 10 so as to be freely opened and closed. The recording paper 20 set on the manual feed tray 110 is separated one by one by the action of the separation roller 111 and the separation pad 112 and is supplied into the apparatus main body 10. These constitute the manual paper supply unit 11. The separated and supplied recording paper 20 passes through the manual paper conveyance path 12, draws a manual conveyance path line 203 and joins the main conveyance path 6, and the nip between the photosensitive drum 30 and the transfer roller 34 by the registration roller pair 7. Introduced into the department. Therefore, recording based on the image information is performed on the manual-feed recording paper 20 as described above. In the image forming apparatus 1 shown in the figure, an optional cassette (not shown) as a multi-stage cassette system can be installed under the recording paper supply cassette 21, and recording from the lower option cassette is performed in the apparatus main body 10. A paper transport path 6 'is formed. This conveyance path 6 'constitutes a part of the main conveyance path 6 when the multistage cassette system is adopted.

  A heat exhaust duct 37 of the fixing device 36 is provided below the discharge tray 42, and an exhaust fan 38 is installed at the exhaust port of the heat exhaust duct 37. In the standard specification apparatus, the upper surface of the exhaust heat duct 37 is the discharge tray 42. In the upper space 100 above the exhaust heat duct 37, a sheet relay conveyance unit 13 which will be described later is installed, and the image reading unit 5 is further installed thereabove. The image reading unit 5 is installed on an image reading scanning unit 50 including an ADF (automatic document feeder) reading unit 51 and an FBS unit (flat bed scanner unit) 52, and can be freely opened and closed on the image reading scanning unit 50. A document pressing plate 53 is included. A scanning carriage 54 equipped with a light source, a mirror, a lens, and a CCD is installed in the image reading scanning unit 50. The scanning carriage 54 can be reciprocated by the FBS unit 52, and is fixed by the ADF reading unit 51. Movement control is performed. On the upper surface of the document pressing plate 53, an ADF document supply tray 55, an ADF mechanism 56, and an ADF document discharge tray 57 are provided. The image reading unit 5 is used for copying a document image or transmitting a facsimile.

  As described above, in the upper space 100 of the exhaust heat duct 37, the sheet relay conveyance unit 13 is installed in a horizontal state so as to be connected to the downstream end portion of the main conveyance path 6 of the apparatus main body 10. A post-processing unit 14 is attached to the side portion 10. The post-processing unit 14 is constituted by each post-processing mechanism unit assembled to a vertical frame 140 attached to the side of the apparatus main body. That is, a plurality of sort trays 141 are supported on the frame body 140 so as to be movable up and down, and in the vicinity of the post-processing discharge roller pair 142 installed corresponding to the discharge side end of the sheet relay conveyance unit 13. In addition, a stapling mechanism unit 143 and a punching mechanism unit 144 are installed. In the example shown in the figure, there are two sort trays 141, but three or more sort trays 141 may be used. These sort trays 141 can be individually moved up and down by a vertical movement mechanism (not shown) provided in the frame 140, and when the sort processing instruction is given, the sort image recording process is performed by the image recording unit 3. The recording paper is appropriately sorted into each sort tray 141 and discharged and accumulated. The staple mechanism unit 143 or the punching mechanism unit 144 also operates based on the staple processing instruction or the punching process instruction, and performs each process on the image-recorded recording paper 20 discharged from the post-processing discharge roller pair 142. The

  The sheet relay conveyance unit 13 is installed in the upper space 100 of the exhaust heat duct 37 so that the image-recorded recording paper 20 discharged from the main conveyance path 6 of the apparatus main body 10 can be relayed and conveyed to the post-processing unit 14. . The sheet relay conveyance unit 13 includes an upper guide member 131 fixed to the apparatus main body 10, a movable lower guide member 132, and sides of the upper guide member 131 and the lower guide member 132 on the back side of the apparatus main body 10. It consists of a link member 133 that connects the sections and a lock member 134. The upper guide member 131 includes a plurality of drive rollers 135 that are driven and transmitted from a drive source (not shown) in the apparatus main body 10, and the lower guide member 132 is driven when combined with the upper guide member 131. A plurality of press rollers 136 that contact the roller 135 are provided. 1 to 3 show that the lower guide member 132 is maintained in the combined state by the lock of the lock member 134 with respect to the upper guide member 131. The lower guide member 132 is formed to be larger so that the back side portion protrudes further to the back side than the back side portion of the upper guide member 131, and both sides of the upper guide member 131 and the lower guide member 132 located on the back side. A link member 133 is pin-coupled between the side portions. Therefore, in the combined state by the locking of the lock member 134, the link member 133 is in a lateral state in which the pin coupling portion with the lower guide member 132 is located on the back side of the pin coupling portion with the upper guide member 131. . When the driving roller 135 is rotationally driven in such a combined state of the upper and lower guide members 131 and 132, the image-recorded recording paper 20 discharged from the main conveyance path 6 is nipped by the driving roller 135 and the press roller 136. Then, it is conveyed toward the post-processing discharge roller pair 142.

  An opening / closing cover 15 is attached to the front side opening 101 in the apparatus main body 10 of the upper space 100. The opening / closing cover 15 functions as a jam access cover used to repair a paper jam when the paper relay / conveyance unit 13 generates a paper jam. That is, when it is notified that a paper jam has occurred in the paper relay transport unit 13, the operator opens the open / close cover 15 and unlocks the lock member 134 of the paper relay transport unit 13. By this unlocking operation, as shown in FIG. 4, the link member 133 swings around the pin coupling portion with the upper guide member 131 as a fulcrum. At this time, since the link member 133 swings from the lateral state as described above, the pin coupling portion with the lower guide member 132 swings toward the front side of the apparatus main body 10, and thereby the lower guide The member 132 descends so as to protrude toward the opening 101 side. As described above, when the lower guide member 132 is released from the combined state with the upper guide member 131, at least the length of the link member 133 is provided between the lower guide member 132 and the upper guide member 131 on the back side. An interval corresponding to is secured. Therefore, when inserting a hand through the opening 101 and taking out the jammed paper, it is possible to insert a hand into the back side, and the jammed paper can be taken out without any trouble. Further, since the lower guide member 132 is lowered so as to protrude toward the opening 101, depending on the jam state, the jammed paper is also placed on the lower guide member 132 as the lower guide member 132 is lowered. The jammed paper can be taken out more easily because the paper may be pushed to the side.

  3 and 4 show an example in which a shelf member 16 is provided at an appropriate location in the upper space 100 where the sheet relay conveyance unit 13 is installed. The shelf member 16 supports the lower guide member 132 in a substantially horizontal state when the lower guide member 132 is released from the combined state with the upper guide member 131. However, the lower guide member 132 may be directly supported on the upper surface of the exhaust heat duct 37, that is, on the discharge tray 42, and these are appropriately selected and adopted as a design matter. Further, in addition to the link member 133, the upper guide member 131 and the lower guide member 132 may be coupled by a link member having the same length on the front side to constitute a parallel link mechanism. Further, the connecting relationship between the link member 133 and the upper guide member 131 and the lower guide member 132 is reversed from that in the illustrated example. When the combined state is released, the lower guide member 132 moves to the back side. You may comprise so that it may descend | fall.

  In the above-described embodiment, an example in which the sheet relay conveyance unit 13 and the post-processing unit 14 are retrofitted to the standard specification apparatus main body 10 as optional units is shown, but an image forming apparatus incorporating these as standard specifications may also be used. good. In this case, the one corresponding to the discharge tray 42 is excluded from the design matters. Further, although the example in which the image recording unit 3 is an electrophotographic image recording unit has been shown, the image recording unit 3 may be another type of image recording unit, and is not limited to a monochrome image recording unit, and may be a color image. The present invention can also be applied to an image forming apparatus including a recording unit.

1 is a schematic longitudinal sectional view showing an embodiment of an image forming apparatus according to the present invention. It is a cross-sectional top view of the part in which the paper relay conveyance unit in the same apparatus was installed. FIG. 3 is a cross-sectional view taken along line XX in FIG. 2. FIG. 4 is a view similar to FIG. 3 showing an operation state of the sheet relay conveyance unit at the time of jam release.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Image forming apparatus 3 Image recording part 6 Recording paper (paper) conveyance path 10 Apparatus main body 13 Paper relay conveyance unit 131 Upper guide member 132 Lower guide member 133 Link member 134 Lock member 135 Drive roller 136 Press roller 14 Post-processing unit 15 Open / close cover 20 Recording paper (paper)

Claims (2)

An apparatus main body, an image recording unit, a post-processing unit for post-processing and discharging the image-recorded paper by the image recording unit, a paper conveyance path for conveying the image-recorded paper, and a downstream side of the paper conveyance path An image forming apparatus comprising a sheet relay conveyance unit installed between an end portion and a post-processing unit,
The sheet relay conveyance unit includes a fixed upper guide member having a plurality of drive rollers, a movable lower guide member having a plurality of press rollers corresponding to the drive rollers, and an upper guide on the back side of the apparatus main body. A link member that connects the side portions of the member and the lower guide member, and a lock member that maintains the upper guide member and the lower guide member in a combined state so that each drive roller and press roller come into contact with each other,
When the lock by the lock member is released, the lower guide member can be lowered by swinging the link member ,
The link member has an upper guide member that swings in a vertical state from a state facing the back side of the apparatus body to a front side of the apparatus body when the lock member is released and the lower guide member is lowered. Connected between the sides of the lower guide member,
An image forming apparatus according to claim 1, wherein the lower guide member protrudes toward the front side of the apparatus main body by the swing of the link member when unlocked . The image forming apparatus according to claim 1 .
An opening / closing cover is attached to the front side of the apparatus main body on which the sheet relay conveyance unit is installed, and the lock member can be locked and unlocked by opening the opening / closing cover. Image forming apparatus.

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