JP2006168887A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent jam from occurring when a paper remains in a device in feeding of the paper from a manual single-paper feeding tray. <P>SOLUTION: A shutter member 144 opens/closes a carrying passage 160 from the manual single-paper feeding tray 141. When the paper 5 is set on the manual single-paper feeding tray 141 to turn on a detection output of a manual single-paper presence/absence sensor 207, it is determined whether or not any active job (JOB) is present. If any active job is present to indicate that there is the remaining paper 5 in the device, after the paper 5 while printing is ejected by interruption of the active JOB, the shutter member 141 is opened to open the carrying passage 160 from the manual single-paper feeding tray 141 to start manual single-paper feeding. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an image forming apparatus.

  As an image forming apparatus such as a printer, a facsimile machine, a copying machine, a printer / fax / copier multifunction machine, for example, a recording head (image forming means) constituted by a liquid discharge head for discharging a recording liquid droplet is used. While transporting a recording medium (paper, recording medium, transfer material, etc.), recording liquid droplets (hereinafter also referred to as ink droplets) are attached to the paper to form an image (recording, printing, Inkjet recording apparatuses that perform printing and printing are also used synonymously), image forming apparatuses that form images by electrophotography, and the like are known.

By the way, in a conventional image forming apparatus, in order to feed a recording medium for forming an image into the apparatus main body, a paper feeding tray on which a large number of recording media can be placed, and a large number of recording media A plurality of paper feeding means such as a paper feeding tray that can accommodate the recording medium and a manual paper feeding tray (portion) for a user to manually feed a recording medium directly.
Japanese Patent Laid-Open No. 10-17179

Here, as described in Patent Document 2, the recording medium fed from the manual paper feed port is fed to the printing unit, and after printing, the recording medium is conveyed again to the manual paper feed port and discharged. As described in Patent Documents 3 and 4, the recording medium can be fed from the paper discharge tray, and after the image is formed on the paused recording medium, the recording medium is again put on the paper discharge tray. There is a recording apparatus in which a manual sheet feeding unit is omitted by discharging paper.
Utility Model Registration No. 3060361 Japanese Patent No. 2698699 Japanese Patent Laid-Open No. 2000-2111768

Further, as described in Patent Document 5, an image in which a recording medium that has been printed on one side is reversed and fed to the other side by the switchback method, and is printed on the other side after being printed. As described in Japanese Patent Application Laid-Open No. 2003-260260, there is also known an image forming apparatus in which a paper feeding cassette is disposed below a reading unit to reduce the size.
Japanese Patent No. 2702533 JP-A-8-110660

  By the way, in an image forming apparatus such as an ink jet recording apparatus, a sheet is fed linearly, and after an image is formed on the sheet, the sheet is conveyed linearly and ejected face up with the printing surface facing up. For example, straight paper discharge for paper, face-down paper discharge in which an image is formed on the paper, and the paper is turned over so that the printing surface faces downward and the paper is discharged face-down is used. In this case, in an image forming apparatus that performs straight sheet discharge, the occupied space of the entire apparatus including discharged sheets becomes large. On the other hand, in an image forming apparatus that performs reverse paper discharge, when printing on paper on which ink such as OHP is difficult to dry, the printing surface may be rubbed against the guide member during reversal, and the image may deteriorate. When using thick paper, it cannot be reversed and may jam.

  In view of this, it is preferable to provide a single manual paper feed unit for feeding a recording medium linearly by hand, in addition to a normal paper feed tray and manual paper feed unit, However, in this case, in order to prevent an increase in the occupied space described above, the single sheet feed unit and the straight sheet discharge tray are provided to be openable and closable with respect to the apparatus main body. Can be considered.

  As described above, when a single sheet feeding unit for manually feeding one recording medium is provided, the manual sheet feeding port is fed like the image forming apparatus described in Patent Document 2 described above. Sheets remain in the apparatus when the same structure is used as the opening and the discharge opening, or the structure in which the discharge tray is also used as the manual feed tray as in the image forming apparatus described in Patent Documents 3 and 4. If paper is fed from the manual paper feed port in this state, a jam will occur.

  Even when a straight paper discharge tray is provided, if the straight paper discharge tray remains in a state where paper cannot be discharged, straight paper discharge cannot be performed when one sheet is manually fed. If jamming occurs, or if paper feeding is not performed at this time, the user interface may be deteriorated, for example, the user may not know the cause of the paper feeding failure and may be mistaken.

  SUMMARY An advantage of some aspects of the invention is that it provides an image forming apparatus that can perform one-sheet manual feeding stably without causing a jam or the like.

  In order to solve the above-described problems, the image forming apparatus according to the present invention is configured so that when a recording medium remains in the apparatus main body, the single sheet feeding unit does not eject the recording medium until the recording medium is discharged. A configuration is provided that includes means for preventing paper feeding.

  Here, a straight discharge tray is provided for linearly transporting and discharging the recording medium fed from the single sheet feeder, and the recording medium discharged to the straight discharge tray remains. It is preferable to provide a means for preventing the sheet feeding from the one-sheet manual sheet feeding unit from being started.

  In this case, a branch detection means for detecting the recording medium is provided at a branching section that switches between discharging to the straight discharge tray and discharging to the discharge tray that reversely discharges the recording medium on which the image is formed, Preferably, the branch detection means also serves as a means for detecting whether or not the recording medium discharged to the straight discharge tray remains.

  In addition, it is preferable that a shutter member that opens and closes the conveyance path from the one-sheet manual sheet feeding unit is provided, and the shutter member closes the conveyance path when the sheet feeding from the one-sheet manual sheet feeding unit is not started.

  An image forming apparatus according to the present invention is provided with an openable and closable straight discharge tray that linearly discharges a recording medium fed from a single manual paper feeder, and feeds paper from a single manual paper feeder. When performing, it is preferable to provide means for prompting an operation to open the straight discharge tray to a dischargeable position.

  Here, it is preferable to provide a shutter member that opens and closes the conveyance path from the one-sheet manual sheet feeding unit, and the shutter member opens the conveyance path when the straight sheet discharge tray is opened to a dischargeable position.

  The image forming apparatus according to the present invention feeds a recording medium from a single manual sheet feeding unit, and discharges the recording medium after image formation to a single manual sheet feeding unit. The feed speed when starting the feeding of the recording medium from the beginning and the feeding speed when discharging the recording medium to the single-sheet manual feeding section are compared with the feeding speed when forming an image on the recording medium. The configuration is low speed.

  The image forming apparatus according to the present invention includes an openable and closable straight paper discharge tray that linearly discharges a recording medium fed from a single manual paper feed unit, and feeds paper from the single manual paper feed unit. When forming an image, the recording medium is discharged to the straight paper discharge tray when the straight paper discharge tray is in the paper discharge enabled position, and one sheet is manually fed when the straight paper discharge tray is in the paper discharge impossible position. The recording medium is discharged to the unit.

According to the image forming apparatus of the present invention, when the recording medium remains in the apparatus main body, the unit that does not start the sheet feeding from the one-sheet manual feeding unit until the recording medium is completely discharged. Therefore, it is possible to carry out stable single manual feeding without jamming due to the fact that no single sheet is manually fed while the recording medium remains in the apparatus main body. .

  According to the image forming apparatus of the present invention, the straight sheet discharge tray that linearly discharges the recording medium fed from the single manual sheet feed unit can be opened and closed, and the single sheet manual sheet feed unit can feed the recording medium. When paper is fed, a means for outputting an instruction to open the straight paper discharge tray to a dischargeable position is provided, so that one sheet is manually fed in a state where paper cannot be discharged to the straight paper discharge tray. This eliminates the possibility of jamming and stable single-sheet manual feeding.

  According to the image forming apparatus of the present invention, when the recording medium is fed from the single manual sheet feeding unit and the recording medium after image formation is discharged to the single manual sheet feeding unit, the single sheet manual feeding is performed. The feed speed when starting to feed the recording medium from the paper section and the feeding speed when discharging the recording medium to the single-sheet manual feeding section are the feeding speed when forming an image on the recording medium. On the other hand, since the configuration is low speed, it is possible to prevent the recording medium from jumping out of the manual sheet feeding unit during paper ejection.

  According to the image forming apparatus of the present invention, the straight sheet discharge tray that linearly discharges the recording medium fed from the single manual sheet feed unit can be opened and closed, and the single sheet manual sheet feed unit can feed the recording medium. When forming an image on paper, the recording medium is ejected to the straight paper ejection tray when the straight paper ejection tray is in the ejectable position, and one sheet is manually fed when the straight paper ejection tray is in the non-ejection position. Since the recording medium is ejected to the paper feed unit, single-sheet manual feeding is no longer performed when paper cannot be ejected to the straight paper ejection tray, and jamming does not occur. Paper can be fed and one sheet can be manually fed quickly.

  Embodiments of the present invention will be described below with reference to the accompanying drawings. An outline of an example of an image forming apparatus according to the present invention will be described with reference to FIGS. 1 is a schematic configuration diagram showing the overall configuration of the image forming apparatus, FIG. 2 is a plan explanatory view of an image forming unit and a sub-scanning conveying unit of the apparatus, FIG. 3 is a side explanatory view, and FIG. FIG. 6 is an explanatory diagram of a sheet conveyance path related to sheet feeding.

  This image forming apparatus includes an image forming unit (means) 2 for forming an image while conveying a sheet and a sub-scanning conveying unit (means) 3 for conveying a sheet inside the apparatus main body 1 (enclosure). And the like, and a sheet 5 is fed one by one from a sheet feeding unit (means) 4 including a sheet feeding cassette provided at the bottom of the apparatus body 1, and the sheet 5 is fed by the sub-scanning conveying unit 3 to the image forming unit 2. In the case of single-sided printing, after the droplets are ejected onto the paper 5 by the image forming unit 2 while being conveyed at a position opposite to the image forming unit 2, in the case of single-sided printing, the apparatus is passed through the paper discharge conveying unit (means) 7. The paper 5 is discharged onto a paper discharge tray 8 formed on the upper surface of the main body 1, and in the case of double-sided printing, it is sent from the middle of the paper discharge conveyance unit 7 to the double-side unit 10 provided at the bottom of the apparatus main body 1, and the switch Back transport, feed again to the sub-scan transport unit 3 and images on both sides It is discharged onto the discharge tray 8 after the form.

  The image forming apparatus also has an image reading unit (scanner) for reading an image above the discharge tray 8 above the apparatus main body 1 as an input system for image data (print data) formed by the image forming unit 2. Part) 11. The image reading unit 11 includes a scanning optical system 15 including an illumination light source 13 and a mirror 14 and a scanning optical system 18 including mirrors 16 and 17. The scanned document image is read as an image signal by the image reading element 20 disposed behind the lens 19, and the read image signal is digitized and subjected to image processing, and the image-processed print data is printed. be able to.

  Further, this image forming apparatus uses an information processing apparatus such as an external personal computer, an image reading apparatus such as an image scanner, and an imaging apparatus such as a digital camera as an input system for image data (print data) formed by the image forming unit 2. For example, print data including image data from the host side can be received via a cable or a network, and the received print data can be processed and printed.

  Here, as shown in FIG. 2, the image forming unit 2 of the image forming apparatus holds the carriage 23 movably in the main scanning direction by the guide rod 21 and a guide stay (not shown), and is driven by the main scanning motor 27. It moves and scans in the main scanning direction via a timing belt 29 spanned between the pulley 28A and the driven pulley 28B.

  A recording head 24 including a droplet discharge head for discharging droplets of each color is mounted on the carriage 23, the carriage 23 is moved in the main scanning direction, and the sheet 5 is transferred to the sheet by the sub-scanning conveyance unit 3. A shuttle type is used in which droplets are ejected from the recording head 24 while feeding in the transport direction (sub-scanning direction) to form an image. A line-type head can also be used.

  The recording head 24 has two droplet discharge heads 24k1 and 24k2 that discharge black (Bk) ink, respectively, and one each that discharges cyan (C) ink, magenta (M) ink, and yellow (Y) ink. Each of the sub-tanks 25 mounted on the carriage 23 is composed of a total of five liquid droplet ejection heads (hereinafter referred to as “recording head 24” when the colors are not distinguished). Of ink is supplied.

  On the other hand, as shown in FIG. 1, a recording liquid cartridge containing black (Bk) ink, cyan (C) ink, magenta (M) ink, and yellow (Y) ink from the front of the apparatus main body 1 to the cartridge mounting portion. Each color ink cartridge 26 can be detachably mounted, and ink is supplied from each color ink cartridge 26 to each color sub-tank 25. The black ink is supplied from one ink cartridge 26 to the two sub tanks 25.

  The recording head 24 uses a piezoelectric element as a pressure generating means (actuator means) for pressurizing the ink in the ink flow path (pressure generation chamber) to deform the vibration plate that forms the wall surface of the ink flow path. A so-called piezo type that discharges ink droplets by changing the volume in the flow channel, or discharges ink droplets with a pressure generated by heating the ink in the ink flow channel using a heating resistor to generate bubbles. The so-called thermal type, the diaphragm that forms the wall surface of the ink flow path and the electrode are placed opposite to each other, and the diaphragm is deformed by the electrostatic force generated between the vibration plate and the electrode, thereby the ink flow path inner volume It is possible to use an electrostatic type or the like that discharges ink droplets by changing the above.

  Further, as shown in FIG. 2, a maintenance / recovery device 121 for maintaining and recovering the nozzle state of the recording head 24 is disposed in the non-printing area on one side in the scanning direction of the carriage 23. The maintenance / recovery device 121 includes five moisturizing caps 122k2, 122k1, 122c, 122m, and 122y for capping the nozzle surfaces of the five recording heads 24 (“moisturizing caps” when colors are not distinguished). 122 ”), a single suction cap 123, a wiper blade 124 for wiping the nozzle surface of the recording head 24, and discharge (empty discharge) of droplets that do not contribute to recording (image formation). For example, an empty discharge receiving member 125 is provided.

  Further, as shown in FIG. 2, in the non-printing area on the other side of the carriage 23 in the scanning direction, droplets that do not contribute to recording (image formation) (empty discharge) are discharged from the five recording heads 24. An empty discharge receiving member 126 is provided. The empty discharge receiving member 126 has five openings 127k2, 127k1, 127c, 127m, and 127y corresponding to the recording head 24 (referred to as “openings 127” when colors are not distinguished).

  As shown in FIG. 3, the sub-scanning conveyance unit 3 is a driving roller for conveying the paper 5 fed from below by changing the conveyance direction by approximately 90 degrees and facing the image forming unit 2. An endless transport belt 31 laid between the transport roller 32 and a driven roller 33 which is a tension roller, and a charging means to which a high voltage as an alternating voltage is applied from a high voltage power source in order to charge the surface of the transport belt 31 A charging roller 34, a guide member 35 that guides the conveyance belt 31 in a region opposite to the image forming unit 2, and two pressing rollers (additions) that press the paper 5 against the conveyance belt 31 at a position facing the conveyance roller 32. Pressure roller 36, two spur rollers 37 that press the top surface of the sheet 5 on which the image is formed by the image forming unit 2, and the sheet 5 on which the image is formed is separated from the conveyance belt 31. And a separation claw 38.

  The transport belt 31 of the sub-scan transport unit 3 is rotated in the paper transport direction (sub-scan direction) in FIG. 2 by rotating the transport roller 32 from the sub-scan motor 131 through the timing belt 132 and the timing roller 133. It is configured to do. The transport belt 31 includes, for example, a surface layer that is a sheet adsorption surface formed of a pure resin material that is not subjected to resistance control, such as ETFE pure material, and a back layer that is subjected to resistance control using carbon with the same material as the surface layer. Although a two-layer structure (medium resistance layer, earth layer) is used, the present invention is not limited to this, and a one-layer structure or a structure of three or more layers may be used.

  In addition, a cleaning unit (mylar is used here) 135 for removing paper dust and the like adhering to the surface of the conveyor belt 31 between the driven roller 33 and the charging roller 34, and the surface of the conveyor belt 31. And a static elimination brush 136 for removing electric charges.

  In addition, a cleaning unit (mylar is used here) 135 for removing paper dust and the like adhering to the surface of the conveyor belt 31 between the driven roller 33 and the charging roller 34, and the surface of the conveyor belt 31. And a static elimination brush 136 for removing electric charges.

  Further, a high-resolution code hole 137 is attached to the shaft 32 a of the transport roller 32, and a transmissive photosensor 138 that detects a slit (not shown) formed in the codewheel 137 is provided, and the codewheel 137 and the photosensor 138 are provided. The rotary encoder is constituted by the above.

  Further, a linear scale (not shown) is formed on the back surface of the conveyor belt 31 (a surface in contact with the outer circumferential surface of the conveyor roller 32), and a reflective photosensor 139 for reading the linear scale is provided. The scale and the photosensor 139 constitute a linear encoder. The linear scale may be formed in a striped pattern by depositing aluminum on the back surface side of the conveyor belt 31 and then flying with a laser beam. Further, the linear scale is provided at a portion where reading by the reflective photosensor 139 is not disturbed by the guide member 35. Further, a joint sensor 140 is provided adjacent to the sensor 139 for detecting a joint of a linear scale provided on the surface on the back surface side of the transport belt 31.

  The paper feed unit 4 can be inserted / removed from the front side of the apparatus main body 1. The paper feed cassette 41 that stacks and stores a large number of sheets 5 and the sheets 5 in the sheet feed cassette 41 are separated and sent out one by one. A sheet feeding roller 42 and a friction pad 43 are provided, and a registration roller 44 that registers the fed sheet 5 is provided. The paper feed unit 4 includes a manual feed tray 46 for stacking and storing a large number of sheets 5, a manual feed roller 47 for feeding the sheets 5 from the manual feed tray 46 one by one, and the apparatus main body 1. On the lower side, a paper feed cassette that is optionally mounted and a transport roller 48 for transporting paper 5 fed from a duplex unit 10 described later are provided. A member for feeding the paper 5 to the sub-scanning conveyance unit 3 such as the paper feed roller 42, the registration roller 44, the manual feed roller 47, and the conveyance roller 48 is a paper feed motor including an HB type stepping motor via an electromagnetic clutch (not shown). (Drive means) 49 is rotationally driven.

  The paper discharge transport unit 7 includes three transport rollers 71a, 71b, and 71c that transport the paper 5 separated by the separation claw 38 of the sub-scan transport unit 3 (referred to as “transport roller 71” when not distinguished). Spurs 72a, 72b, 72c (also referred to as “spurs 72”), a lower guide portion 73 and an upper guide portion 74 for guiding the paper 5 conveyed between the paper discharge roller 71 and the spur 72, and a lower guide. A reversing roller pair 77 and a reversing discharge for reversing the sheet 5 fed from between the section 73 and the upper guide section 74 through the reversing sheet discharging path 81 which is the first transport path and sending it to the sheet discharging tray 8 face down. A pair of paper rollers 78. A conveyance path for conveying the sheet 5 between the lower guide portion 73 and the upper guide portion 74 is referred to as a conveyance path 70.

  Note that, on the exit side of the conveyance path 70, a first discharge path 81 for reverse discharge to the discharge tray 8, a second discharge path 82 for discharging to a straight discharge tray 181 described later, and both sides A branch mechanism 60 is provided for switching to the transport path for any of the units 10.

  The duplex unit 10 transports the fed paper 5 from the side surface of the apparatus main body 1 and transports it in the horizontal direction following the vertical duplex transport path 90c that constitutes the vertical duplex transport path 90c that transports it downward. A horizontal conveyance unit 101b that forms a horizontal take-in conveyance path 90a and a switchback conveyance path 90b is integrally provided.

  The vertical double-sided conveyance path 90c is provided with a double-sided entrance roller pair 91 for conveying the fed paper 5 downward and a conveyance roller pair 92 for sending it out to the horizontal taking-in conveyance path 90a. 93, and the switchback conveyance path 90b includes a double-sided exit roller 94 composed of a reverse roller for reversing and refeeding the sheet 5 fed from the take-in conveyance path 90a and three double-sided conveyance roller pairs 95. Yes.

  Further, the branch plate 96 for switching between the conveyance path of the sheet 5 from the take-in conveyance path 90a to the switchback conveyance path 90b and the conveyance path for refeeding from the switchback conveyance path 90b to the conveyance roller pair 48 can be swung. Provided. The branch plate 96 can swing between a switchback side position shown by a solid line in FIG. 1 and a refeeding side position shown by a broken line.

  The sheet 5 sent out from the duplex unit 10 is sent into the above-described transport roller 48 and sent to the registration roller 44.

  When the sheet 5 fed from the sheet feeding cassette 41, the manual sheet feeding tray 46, and the duplex unit 10 described above is conveyed by the registration roller 44, the conveyance roller 32 of the sub-scanning conveyance unit 3 and As shown in FIG. 1, the opening / closing guide plate 110 can be swung to form a loop (slack) on the paper 5 between the presser rollers 36 and the registration roller 44 to prevent back tension on the paper 5. Provided.

  When the sheet 5 is sent from the registration roller 44 to the sub-scanning conveyance unit 3, the open / close guide plate 110 swings in the direction indicated by the arrow to guide the sheet 5. At the timing reached, the state returns to the state shown in FIG.

  Further, in this image forming apparatus, in order to perform manual sheet feeding, a single sheet feeding tray 141 is provided on one side of the apparatus body 1 with respect to the apparatus body 1 as shown in FIG. In order to manually feed one sheet, the one-sheet manual feed tray 141 is folded to the position shown in the phantom line. The manually fed paper 5 from the single manual paper feed tray 141 is guided by the upper surface of the open / close guide plate 110 and linearly between the transport roller 32 and the pressing roller 36 of the sub-scanning transport unit 3 as it is. Can be plugged in.

  On the other hand, a straight discharge tray 181 is provided on the other side of the apparatus main body 1 so as to be openable and closable (can be opened and lowered) in order to discharge the sheet 5 on which the image has been formed straight up face up. By opening (opening) the straight paper discharge tray 181, the paper 5 fed from the lower guide portion 73 and the upper guide portion 74 to the paper discharge conveyance portion 7 is discharged linearly to the straight paper discharge tray 181. A straight paper discharge path 82 as a second paper discharge path is formed.

  As a result, for example, when using paper that is difficult to convey in a curved line, such as OHP or thick paper, one sheet can be manually fed from the single sheet feed tray 141 and the sheet 5 can be conveyed linearly to the straight discharge tray 181. become able to. Of course, even normal paper such as plain paper can be fed from the single manual feed tray 141 and discharged linearly to the straight discharge tray 181.

  Here, the arrangement of various sensors will be described with reference to FIG. 4. In order to detect the paper 5, the conveyance registration sensor 201 is disposed upstream of the registration roller 44, the conveyance roller 32, the upstream pressing roller 36, and the like. The image registration sensor 203 for registering the image writing position is provided on the downstream side of the presser roller 36 on the downstream side (inlet of the image forming unit 2). A print unit exit sensor 204 is disposed at the exit (on the front side of the transport roller 71a), a branch sensor 205 is disposed on the branch mechanism 60, and a paper discharge sensor 206 is disposed on the front side of the paper discharge roller pair 78. . In addition, a manual sheet presence / absence sensor 207 for detecting that the sheet 5 is set on the one-sheet manual sheet feeding tray 141 is disposed.

  Further, a manual tray opening detection sensor 211 for detecting opening / closing of the single manual feeding tray 141 and a paper discharge tray opening detection sensor 212 for detecting opening / closing of the straight paper discharge tray 181 are arranged. Although not shown in FIG. 4, a double-sided inlet sensor is provided on the inlet side of the horizontal take-in conveyance path 90a of the duplex unit 10, and between the outlet side of the horizontal take-up conveyance path 90a and the inlet side of the switchback conveyance path 90b. Each reversal sensor is arranged.

Next, the configuration of the one-sheet manual sheet feeding unit will be described with reference to FIGS. 5 is an explanatory perspective view of the single sheet manual feeding unit, and FIG. 6 is an explanatory side view.
First, the opening / closing guide plate 110 and its swinging mechanism will be described. The opening / closing guide plate 110 serving as the opening / closing guide member is disposed so as to be swingable by the support shaft 111, and the tension roller 112 and the registration roller 44 are sub-scanned and conveyed. It is held at the loop formation position (position in FIG. 6) withdrawn from the conveyance path with the section 3.

  The guide surface 110 a curved in the vertical direction of the open / close guide plate 110 is a guide surface for guiding the paper 5 fed from the registration roller 44, and the horizontal guide surface 110 b is a paper manually fed from the single manual paper feed tray 141. 5 is a guide surface for guiding 5. By using the upper surface of the open / close guide plate 110 also as a manual guide surface for one sheet, the configuration is simplified.

  On the other hand, in order to swing the opening / closing guide plate 110, an opening / closing guide plate solenoid 113 as driving means is arranged, and a swing arm 114 is attached to a plunger 113a of the opening / closing guide plate solenoid 113, and the tip of the swing arm 114 is placed. When the opening / closing guide plate solenoid 113 is driven by bringing the portion into contact with the contact portion 115 formed integrally with the opening / closing guide plate 110, the plunger 113a is pulled and the swing arm 114 swings in the direction of the arrow in FIG. Then, the open / close guide plate 110 is swung in the direction of the arrow in the same figure against the urging force of the tension spring 112.

  In this case, when the paper 5 fed from the registration roller 44 is guided to the sub-scanning conveyance unit 3, the opening / closing guide plate solenoid 113 is driven to guide the paper 5 fed out, and the opening / closing guide plate solenoid 113 is driven at a predetermined timing. 6 is returned to the initial position shown in FIG. 6 so that a slack (loop) can be formed on the paper 5 between the registration roller 44 and the sub-scanning conveyance unit 3.

  Next, as described above, the single manual paper feed tray 141 is attached to the apparatus main body 1 by the support shaft 142 so as to be openable and closable. A shutter member 144 that opens and closes the manual feed port 143 is provided inside the single manual feed tray 141 so as to be swingable by a support shaft 145.

  The shutter member 144 includes an arm portion 144 a provided with a stopper portion 146 at the front end portion that can shield the paper 5 manually fed from the single manual paper feed tray 141, and an arm portion for interlocking with the opening / closing guide plate 110. 144b, and an engagement roller 147 that engages with an engagement portion 116 that is integrally formed with the opening / closing guide plate 110 is rotatably provided at the distal end portion of the arm portion 144b. The shutter member 144 is in the state of FIG. 6 in which the arm portion 144b does not engage with the open / close guide plate 110 in a steady state, that is, does not interlock with the swinging of the open / close guide plate 110.

  In order to switch the shutter member 144 to a position interlocked with the swinging of the opening / closing guide plate 110 by engaging the arm portion 144b of the shutter member 144 with the opening / closing guide plate 110, an electrical driving unit as a switching unit is used. A certain shutter switching solenoid 150 is arranged, and one end of a swing arm 152 that swingably supports a support shaft 151 is connected to a plunger 150a of the shutter switch solenoid 150, and the other end of the swing arm 152 is connected to a shutter. It arrange | positions so that the arm part 144b of the member 144 can contact | abut. By driving the shutter switching solenoid 150, the shutter member 144 swings in the direction of the arrow in FIG. 6, the arm 144b engages with the engaging portion 116 of the opening / closing guide plate 110, and the shutter member 144 moves to the opening / closing guide. The position is switched to the position interlocked with the swing of the plate 110.

Next, the operation of the one-sheet manual sheet feeding unit will be described with reference to FIGS. Each figure is an explanatory side view similar to FIG.
First, from the state shown in FIG. 6, the single manual paper feed tray 141 is opened in the direction of arrow A, and the single manual paper feed tray 141 is made usable as shown in FIG. Thereafter, the shutter switching solenoid 150 is driven (turned on) at a required timing, so that the swing arm 152 is swung in the arrow B direction and the shutter member 144 is swung in the arrow C direction. 8, the stopper portion 146 of the shutter member 144 swings to a position where the one-sheet manual feeding path 160 is opened, and in this state, the arm portion 141b of the shutter member 144 is engaged with the opening / closing guide plate 110. The shutter 116 can be engaged with the portion 116, that is, the shutter member 144 is in a position interlocked with the opening / closing guide plate 100.

  Prior to this state, the stopper portion 146 of the shutter member 144 is positioned on the one-sheet manual feed path 160 and the manual feed port 143 is closed, and the sheet 5 is manually fed from the one-sheet manual feed tray 141. Even if paper is to be fed, the paper is not fed because it is restricted by the stopper 146.

  Therefore, by driving the open / close guide plate solenoid 113, the swing arm 114 swings in the direction indicated by the arrow D, thereby swinging the open / close guide plate 110 in the direction indicated by the arrow E. At this time, as shown in FIG. Since the engaging portion 116 of the opening / closing guide plate 110 is engaged with the roller 147 of the arm portion 144b of the shutter member 144, the shutter member 144 and the opening / closing guide plate 110 can be interlocked, and the upper surface 110b of the opening / closing guide plate 110 is It is possible to guide the manually fed paper.

  As a result, the manual sheet feeding port 143 is opened and the one-sheet manual sheet feeding path 160 is opened, and the sheet 5 is manually fed to the sub-scanning conveyance unit 3 using the one-sheet manual sheet feeding tray 141. Will be able to.

  After the arm portion 144b of the shutter member 144 is engaged with the open / close guide plate 110, the shutter member 144 is opened even if the swing arm 152 is returned to the initial position by the shutter switching solenoid 150. Does not affect operation.

  That is, when the shutter switching solenoid 150 is ON, the shutter member 144 itself swings to the open position, but since the solenoid 150 is small, the plunger 150a is sucked (the shutter member 144 is open). Since the shutter member 144 swings to the open position shown in FIG. 9, the shutter member 144 is held open by the solenoid 114 in conjunction with the open / close guide plate 110, while the shutter switching solenoid 150 Is turned off.

  In this way, by providing a swingable shutter member that opens and closes the manual paper feed port from the single manual paper feed tray, the single manual paper feed tray can be manually fed when paper remains in the apparatus. Even when the paper is ready (use state), it is possible to keep the manual feed conveyance path closed, and to prevent jamming due to manual feed.

Next, an outline of the control unit of the image forming apparatus will be described with reference to the block diagram of FIG.
The control unit 300 retains data even when the power of the apparatus is shut off, the CPU 301, the ROM 302 that stores programs executed by the CPU 301 and other fixed data, the RAM 303 that temporarily stores image data and the like. Control of the entire apparatus, including a non-volatile memory (NVRAM) 304 and an ASIC 305 that processes input / output signals for performing various signal processing and rearrangement on image data and other input / output signals for controlling the entire apparatus. A main control unit 310 is provided.

  The control unit 300 is interposed between the host side and the main control unit 310, and includes an external I / F 311 for transmitting and receiving data and signals, and a head driver for driving and controlling the recording head 24. Sub-scanning based on the detection results of the head drive control unit 312 including the main scanning drive unit (motor driver) 313 for driving the main scanning motor 27 that moves and scans the carriage 23, the rotary encoder 138A, and the linear encoder 139A. A sub-scanning drive unit 314 for driving the motor 131, a paper feed drive unit 315 for driving the paper feed motor 49, and a discharge motor for driving each roller of the paper discharge unit 7 are driven. A paper drive unit 316, a double-sided drive unit 317 for driving a double-sided paper refeed motor 99 that drives each roller of the double-sided unit 10, and the maintenance and recovery mechanism 12 Includes a recovery system driving portion 318 for driving the maintenance and recovery motor 129 for driving, and AC bias supply unit 319 which co subjected AC bias to the charging belt 34.

  Further, the control unit 300 includes a solenoid driving unit (driver) 322 for driving various solenoids (SOL) 321 including the opening / closing guide plate solenoid 113 and the shutter solenoid 150 described above, and an electromagnetic cracking 323 related to sheet feeding. And a scanner control unit 325 for controlling the image reading unit 11.

  Further, the main control unit 310 includes various sensors 201 to 206 that detect the above-described paper, a manual sheet presence / absence sensor 207, a sensor 211 that detects opening / closing of the one-sheet manual sheet feeding tray 141, and opening / closing of the straight sheet discharge tray 181. An operation / display unit 327 including various sensors such as a numeric keypad and a print start key provided on the apparatus main body 1 and various displays, and various detection signals from sensors 326 including the sensor 212 to be detected and other sensors. The necessary key input is taken in and the display information is output.

  The control of the image forming operation by the control unit 300 will be briefly described. By applying a high voltage of a positive and negative rectangular wave, which is an alternating voltage, from the AC bias supply unit 319 to the charging roller 34, the charging roller 34 is moved to the conveying belt. Since it is in contact with the insulating layer (surface layer) 31, positive and negative charges are alternately applied to the surface layer of the conveying belt 31 in a band shape in the conveying direction of the conveying belt 31, and the predetermined amount is applied on the conveying belt 31. The charging is performed with the charging width of 1 to generate an unequal electric field.

  Therefore, the sheet 5 is fed from the sheet feeding unit 4, the manual sheet feeding unit 46, the duplex unit 10, the one-sheet manual sheet feeding tray 141, and the positive and negative charges between the transport roller 32 and the pressing roller 36 are generated. When the sheet 5 is fed onto the conveyor belt 31 where an unequal electric field is generated, the sheet 5 is instantly polarized according to the direction of the electric field, and is attracted onto the conveyor belt 31 by electrostatic adsorption force. It is transported as the transport belt 31 moves.

  Then, while the paper 5 is intermittently transported by the transport belt 31, an image is formed (printed) by ejecting recording liquid droplets from the recording head 24 on the paper 5 according to the print data. The front end side of the sheet 5 is separated from the conveyor belt 31 by the separation claw 38 and is discharged to the sheet discharge tray 8 and the straight sheet discharge tray 181 as appropriate by the sheet discharge conveyance unit 7 or sent to the duplex unit 10. Then, after the other side image is formed, the paper is discharged.

Next, a first example of manual sheet feeding processing when one sheet is manually fed using the one-sheet manual sheet feeding tray 141 will be described with reference to FIG.
When the single-sheet manual feed tray 141 is opened and the sheet 5 is set on the single-sheet manual feed tray 141, and the detection output of the single-sheet manual feed presence sensor 207 is turned ON, an active job (JOB) If there is a job in operation (JOB), the paper 5 remains in the apparatus. Therefore, the job in operation is interrupted and the paper being printed in the apparatus is printed. The operation of discharging 5 is performed. At this time, since the shutter member 141 closes the manual paper feed port 143 as shown in FIG. 7 described above, the paper 5 cannot be fed manually.

  As described above, when there is a sheet remaining in the apparatus main body, a unit that does not start feeding from the single manual sheet feeding tray until the discharge of the sheet is completed is provided. One-sheet manual feeding is not performed in the remaining state, jamming does not occur, and stable one-sheet manual feeding can be performed.

  Then, it is determined whether or not the branch sensor 205 is in an ON state and waits until the branch sensor 205 is not in an ON state. That is, as described later, when the sheet 5 is discharged straight to the straight discharge tray 181, the branch sensor 205 is turned on when the discharged sheet 5 remains on the straight discharge tray 181. While the branch sensor 205 is ON, the sheet 5 discharged on the straight sheet discharge tray 181 remains, so that one sheet is not manually fed during this period.

  As a result, when paper is discharged using the straight paper discharge tray 181 such as when one sheet is manually fed, the straight paper discharge tray 181 can be used to discharge one sheet of paper. It is possible to prevent the sheet 5 on the tray 181 from being pushed out by the next sheet 5 and jumping out of the sheet discharge tray 181 or jamming without being discharged onto the straight sheet discharge tray 181 well.

  In this way, when the sheet 5 runs out in the apparatus main body 1 and on the straight discharge tray 181, as described above, the shutter switching solenoid 150 is driven (ON) to the state shown in FIG. For example, 500 msec). Thereafter, the open / close guide plate solenoid 113 is driven (ON), and the shutter member 141 opens the manual sheet feed port 143 (single sheet manual conveyance path 160) as shown in FIGS. 9 and 10, and the open / close guide plate 110 is manually inserted. The sheet to be guided can be guided, and after a predetermined time (for example, 500 msec) has elapsed, the shutter switching solenoid 150 is not driven (OFF).

  As a result, the shutter member 141 is opened, and one sheet of paper 5 can be manually fed (inserted) from the one-sheet manual feed tray 141, the entrance sensor 202 of the conveyor belt 31 is turned on, and the start is started. When instructed, an image is formed on a single manually fed sheet 5 fed based on the detection timing of the image registration sensor 203. When the printing unit entrance sensor 202 detects passage of the rear end of the sheet 5 (when it is turned OFF), the open / close guide plate solenoid 113 is not driven (OFF). Paper is discharged onto a paper discharge tray 181.

Next, a second example of the manual sheet feeding process will be described with reference to FIG.
Similarly to the first example described above, when the single manual paper feed tray 141 is opened and the paper 5 is set on the single manual paper feed tray 141, the detection output of the single manual paper feed sensor 207 is turned on. Then, it is determined whether or not there is an active job (JOB). If there is an active job (JOB), the paper 5 remains in the apparatus, so an interrupt is applied to the active job. Then, the operation of discharging the paper 5 being printed in the apparatus is performed.

  Thereafter, the detection output of the straight discharge tray open / close detection sensor 212 is checked to determine whether or not the straight discharge tray 181 is open (it is in a discharge enabled state). At this time, if the straight paper discharge tray 181 is not opened, that is, if the straight paper discharge tray 181 is closed, the straight paper discharge tray 181 cannot be discharged. A message prompting the user to open the paper tray 181 is displayed, it is determined whether or not a predetermined time has elapsed, and these processes are repeated until the predetermined time elapses. When the paper discharge tray 181 does not open, the process shifts to a paper feed / discharge printing process in which the single manual feed tray 141, which will be described later, is used as a discharge tray, and printing by single manual feed is started.

  That is, if one sheet is manually fed using the straight sheet discharge tray 181 in a state where the straight sheet discharge tray 181 is not opened, a jam occurs, so that the straight sheet discharge tray 181 is opened to the operator. By prompting, jamming is prevented, and jamming is prevented by not starting manual sheet feeding until the straight sheet discharge tray 181 is opened.

  If the manual sheet feeding is not started indefinitely unless the straight sheet discharge tray 181 is opened, the user may not know the cause of the inability to print. When it does not open, it shifts to the paper feed / discharge printing process and starts printing by manual sheet feeding for the convenience of the user.

  On the other hand, when the straight paper discharge tray 181 is opened and ready for paper discharge, it is determined whether or not the branch sensor 205 is in the ON state, as in the first example described above. It is determined whether or not a predetermined time has elapsed in the ON state, and these processes are repeated until the predetermined time elapses. If the branch sensor 205 does not turn OFF even after the predetermined time elapses, the same supply is performed. The process proceeds to the paper discharge / printing process. Also in this case, it is preferable to output to the operation / display unit 327 a message prompting the user to remove the paper on the straight paper discharge tray 181.

  In other words, as described above, even if the straight paper discharge tray 181 is open, if one sheet is manually fed while the paper remains on the straight paper discharge tray 181, the paper on the straight paper discharge tray 181 is discharged. Since jamming may occur because the paper is obstructed, manual sheet feeding is not started while the sheet remains on the straight sheet discharge tray 181, but one sheet is manually fed while waiting. Therefore, when the predetermined time has elapsed, the process is shifted to the paper supply / discharge printing process for the convenience of the user.

  When the branch sensor 205 is turned off and can be discharged to the straight discharge tray 181, the conveyance path from the single manual feed tray 141 is closed as in the first example described above. The shutter member 144 is opened, an image is formed on a sheet that is manually fed, and the sheet is discharged onto the straight discharge tray 181.

Next, the paper supply / discharge printing process will be described with reference to FIG.
In this process, the shutter member 141 is opened to open the conveyance path 160 from the single manual paper feed tray 141, and whether or not the print unit entrance sensor 202 is turned on, that is, the single manual paper feed tray 141. It is determined whether or not a sheet is inserted. When the sheet is inserted from the single manual sheet feeding tray 141 and the print unit entrance sensor 202 is turned on, the conveyor belt 31 is rotated forward at a low speed to pre-feed the inserted sheet 5 by a predetermined amount. And stop.

  Thereafter, when a print instruction from the operation / display unit 327 or a print start command from an external host is received, a required image is formed by the recording head 24 while intermittently conveying the paper 5 as described above. At this time, the conveyor belt 31 is rotated forward at a normal printing speed (high speed).

  When printing on the paper 5 is completed, the transport belt 31 is reversed at a high speed to start a transport operation in a direction to return the paper 5 on which the printing has been completed to the single manual feed tray 141. It is determined whether or not the manual sheet presence / absence sensor 207 is turned on, that is, whether or not the leading end of the sheet 5 on which printing has been completed has returned to the single manual sheet feed tray 141. Is turned on, the conveyance belt 31 is reversed at a low speed to decrease the discharge conveyance speed of the paper 5, and when the print unit entrance sensor 202 is turned off, that is, the rear end of the paper 5 causes the conveyance belt 31 to move. When the sheet is pulled out, the conveyance belt 31 is stopped, and when the one-sheet manual sheet presence / absence sensor 207 is turned off, the shutter member 141 is closed and the conveyance path 160 is closed.

  As described above, when paper is fed from the single manual paper feeder and the paper after image formation is discharged to the single manual paper feeder, when feeding paper from the single manual paper feeder is started. Paper feed from the single-sheet manual feed tray by lowering the feed speed and the feed speed when ejecting paper to the single-sheet manual feed unit to the feed speed when forming images on the paper. Can be slowly pulled out and discharged to the manual sheet feeding tray.

1 is a schematic configuration diagram illustrating an overall configuration of an image forming apparatus according to the present invention. 2 is an explanatory plan view of an image forming unit and a sub-scanning conveyance unit of the apparatus. It is a side explanatory view similarly. It is explanatory drawing similarly used for description of a conveyance path | route. FIG. 6 is a perspective view for explaining the configuration of the single manual sheet feeding unit. It is a side explanatory view similarly. FIG. 6 is an explanatory side view illustrating a state in which the single manual sheet feeding tray is opened. It is side explanatory drawing of the state which similarly driven the shutter solenoid. It is a side explanatory view when the open / close guide plate solenoid is similarly driven. It is side explanatory drawing of a state where the shutter member opened similarly. 2 is a block diagram illustrating an overview of a control unit of the image forming apparatus. FIG. It is a flowchart with which it uses for description of the 1st example of the process at the time of the 1 sheet manual printing by the control part. It is a flowchart with which it uses for description of the 2nd example of the 1 sheet manual printing process by the control part. FIG. 6 is a flowchart for explaining a paper feed / discharge printing process of the one-sheet manual printing process.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Apparatus main body 2 ... Image formation part 3 ... Sub-scanning conveyance part 4 ... Paper feed part 5 ... Paper (recording medium)
DESCRIPTION OF SYMBOLS 7 ... Paper discharge conveyance part 8 ... Paper discharge tray 10 ... Duplex unit 11 ... Image reading part 23 ... Carriage 24 ... Recording head 31 ... Conveyance belt 32 ... Conveyance roller 34 ... Charging roller 110 ... Opening / closing guide plate 113 ... Opening / closing guide plate solenoid 141: Single sheet feed tray 143: Manual sheet feed port 144 ... Shutter member 150 ... Shutter solenoid 160 ... Single sheet manual feed path

Claims (8)

  In an image forming apparatus provided with a single sheet feeding unit for manually feeding a single recording medium, when the recording medium remains in the apparatus main body, the ejection of the recording medium is completed. An image forming apparatus comprising: means for preventing the sheet feeding from the one-sheet manual sheet feeding unit until the sheet feeding is started.   The image forming apparatus according to claim 1, further comprising a straight discharge tray for linearly conveying and discharging the recording medium fed from the one-sheet manual sheet feeding unit. An image forming apparatus comprising: means for preventing paper feeding from the one-sheet manual paper feeding unit when a discharged recording medium remains.   The image forming apparatus according to claim 2, wherein the recording target is switched to a branching unit that switches between discharge to the straight discharge tray and discharge to a discharge tray that reversely discharges a recording medium on which an image is formed. A branch detection unit for detecting a medium is provided, and the branch detection unit also serves as a unit for detecting whether or not the recording medium discharged to the straight discharge tray remains. apparatus.   4. The image forming apparatus according to claim 1, further comprising a shutter member that opens and closes a conveyance path from the one-sheet manual sheet feeding unit, and does not start feeding from the one-sheet manual sheet feeding unit. An image forming apparatus, wherein the shutter member closes the conveyance path.   In an image forming apparatus including a single manual sheet feeding unit for manually feeding a single recording medium, a straight line that linearly ejects the recording medium fed from the single manual sheet feeding unit A discharge tray is provided so as to be openable and closable, and means for outputting a message for prompting an operation to open the straight discharge tray to a dischargeable position when paper is fed from the one-sheet manual paper feed unit. An image forming apparatus.   6. The image forming apparatus according to claim 5, wherein a shutter member that opens and closes a conveyance path from the one-sheet manual sheet feeding unit is provided, and the shutter member is opened when the straight sheet discharge tray is opened to a sheet dischargeable position. An image forming apparatus, wherein the conveyance path is opened.   A one-sheet manual feeding unit for manually feeding one recording medium is provided, the recording medium is fed from the one-sheet manual feeding unit, and the recording medium after image formation is the one sheet An image forming apparatus that discharges paper to a manual paper feed unit, the feed speed when starting to feed the recording medium from the single manual paper feed unit and the recording medium to the single manual paper feed unit An image forming apparatus, characterized in that a feeding speed when paper is lower than a feeding speed when an image is formed on a recording medium. In an image forming apparatus including a single manual sheet feeding unit for manually feeding a single recording medium, a straight line for linearly discharging the recording medium fed from the single manual sheet feeding unit A discharge tray is provided that can be opened and closed. When an image is formed by feeding from the one-sheet manual feed unit, a recording medium is placed on the straight discharge tray when the straight discharge tray is in a dischargeable position. An image forming apparatus, wherein the recording medium is discharged and the recording medium is discharged to the one-sheet manual sheet feeding portion when the straight discharge tray is in a position where discharge is not possible.

Images