JP2014065293A - Image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem that an apparatus size in a width direction increases and a maintenance mechanism becomes complex, when including an image forming part for discharging droplets in a horizontal direction.SOLUTION: An image forming apparatus includes: a paper sheet feed tray 4 below an apparatus body; a paper sheet discharge tray 7 above the apparatus body; and an image forming part 2 and a maintenance unit 9 disposed within a space surrounded by a conveyance mechanism part 5 for conveying paper sheet from the paper sheet feed part 4 to the paper sheet discharge part 7. The maintenance unit 9 is disposed in a position below the image forming part 2, and a carriage 23 loaded with a recording head 24 of the image forming part 2 is provided displaceably between an image forming position at which droplets are discharged toward a horizontal direction from the recording head 24 and a maintenance position at which the recording head 24 can face the maintenance unit 9. The maintenance unit 9 is disposed movably between the maintenance position at which a nozzle surface 124 of the recording head 24 is capped by a cap 91; and a retreat position withdrawn from the maintenance position.

Description

  The present invention relates to an image forming apparatus, and more particularly to an image forming apparatus including a recording head that discharges droplets.

  As an image forming apparatus such as a printer, a facsimile machine, a copying apparatus, a plotter, and a complex machine of these, for example, an ink jet recording apparatus is known as an image forming apparatus of a liquid discharge recording method using a recording head for discharging ink droplets. .

  As a conventional image forming apparatus, a recording head is arranged so as to eject droplets in a horizontal direction, and maintenance means (maintenance recovery mechanism) for maintaining and recovering the recording head is arranged in a non-printing area. Known (Patent Document 1).

JP 2012-1116055 A

  However, in the configuration disclosed in Patent Document 1 described above, the maintenance unit is arranged in the non-printing area in the main scanning direction of the carriage on which the recording head is mounted on the same side as the conveying unit that conveys the recording medium. Therefore, there is a problem that the size in the width direction of the apparatus becomes large.

  The present invention has been made in view of the above problems, and an object thereof is to reduce the size of the apparatus.

In order to solve the above problems, an image forming apparatus according to the present invention provides:
Image forming means including a recording head having a nozzle for discharging droplets;
A conveying means for conveying a recording medium facing the image forming means;
A cap for capping the nozzle surface of the recording head, and maintenance means for maintaining the recording head,
The conveying unit and the maintenance unit are arranged on opposite sides of the image forming unit,
The image forming means is provided so as to be displaceable between an image forming position where the droplets are discharged from the recording head in a horizontal direction and a maintenance position where the recording head can face the maintenance means,
The maintenance means is configured to be movable between a maintenance position where the nozzle surface of the recording head is capped by the cap and a retracted position retracted from the maintenance position.

  According to the image forming apparatus of the present invention, it is possible to reduce the size of the apparatus.

FIG. 2 is a side explanatory view of a mechanism unit of the image forming apparatus according to the first embodiment of the present invention. It is a back surface explanatory drawing used for description of the mechanism part. It is side surface explanatory drawing used for description of the movement of the carriage and maintenance unit of the embodiment. It is side surface explanatory drawing of the mechanism part of the image forming apparatus which concerns on 2nd Embodiment of this invention. It is a perspective explanatory drawing of the conveyance belt of the mechanism part. It is side surface explanatory drawing of the mechanism part of the image forming apparatus which concerns on 3rd Embodiment of this invention. It is side surface explanatory drawing used for description of cartridge replacement | exchange of the embodiment. It is a side explanatory view of the mechanism part of the image forming device concerning a 4th embodiment of the present invention. It is side surface explanatory drawing used for description of the movement of the carriage and maintenance unit of the embodiment. It is side surface explanatory drawing used for description of cartridge replacement | exchange of the embodiment. FIG. 10 is a side explanatory view of a mechanism unit of an image forming apparatus according to a fifth embodiment of the present invention. It is side surface explanatory drawing of the mechanism part of the image forming apparatus which concerns on 6th Embodiment of this invention. FIG. 10 is a schematic side explanatory view of a printing mechanism unit of an image forming apparatus according to a seventh embodiment of the present invention. It is a typical side surface explanatory view of the mechanism part used for explanation at the time of maintenance operation shift about the composition concerning maintenance in the embodiment. It is a typical side surface explanatory view of a mechanism part similarly provided for explanation at the time of maintenance operation. It is front explanatory drawing of the mechanism part in the state in which the maintenance means in the embodiment exists in a retracted position. It is front explanatory drawing of a mechanism part in the state where a maintenance means is also in a maintenance position. It is typical side surface explanatory drawing of the mechanism part in 8th Embodiment of this invention. It is typical side surface explanatory drawing of the mechanism part with which it uses for description at the time of printing operation of 9th Embodiment of this invention. It is a typical side surface explanatory view of a mechanism part similarly provided for explanation at the time of maintenance operation. It is front explanatory drawing of the mechanism part similarly provided for description at the time of printing operation. It is front explanatory drawing of the mechanism part similarly provided for description at the time of maintenance operation | movement. It is side surface explanatory drawing when the front cover used for description of 10th Embodiment of this invention is open | released and a carriage exists in a printing position. FIG. 6 is an explanatory side view when the front cover is opened and the carriage is in the maintenance position.

  Embodiments of the present invention will be described below with reference to the accompanying drawings. First, an image forming apparatus according to a first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is an explanatory side view of a mechanism portion of the image forming apparatus, and FIG. 2 is an explanatory rear view for explaining the mechanism portion.

  This image forming apparatus is a serial type image forming apparatus. The apparatus main body includes an image forming unit 2 as an image forming unit, a transport mechanism unit 5 as a transport unit, and the like. (Including a paper cassette and used in the meaning of a paper feed unit).

  Then, the paper 10 fed from the paper feed tray 4 is taken in, and the paper 10 is intermittently transported in the vertical direction (direction along the vertical direction) by the transport mechanism unit 5, while being horizontally moved by the image forming unit 2. A droplet is ejected to record a required image. Thereafter, the sheet 10 on which the image is formed is further conveyed upward through the sheet discharge conveyance unit 6, and the sheet 10 is discharged to a sheet discharge tray 7 which is a sheet discharge unit provided on the upper side of the apparatus main body.

  When performing double-sided printing, after the printing on one side (front surface) is completed, the paper 10 is taken into the reversing unit 8 from the paper discharge conveyance unit 6 and conveyed by the conveyance mechanism unit 5 in the reverse direction (downward). The other side (back side) is reversed and sent to the transport mechanism unit 5 again. Then, after the other side (back side) printing of the paper 10 is finished, the paper 10 is discharged to the paper discharge tray 7.

  Here, the image forming unit 2 movably holds a carriage 23 on which the recording head 24 is mounted with a main guide member 21 and a secondary guide member 22 that are horizontally mounted between the left and right side plates 101L and 101R. The carriage 23 is moved and scanned in the main scanning direction by a main scanning motor of a carriage moving mechanism (not shown) via a timing belt spanned between the driving pulley and the driven pulley.

  The carriage 23 has recording heads 24a and 24b composed of liquid ejection heads for ejecting ink droplets of yellow (Y), magenta (M), cyan (C), and black (K). A recording head 24 ") is mounted. The recording head 24 is mounted with a nozzle row composed of a plurality of nozzles arranged in the sub-scanning direction orthogonal to the main scanning direction and the droplet discharge direction oriented in the horizontal direction. That is, a horizontal driving method is employed in which a nozzle surface on which nozzles for discharging droplets are formed is arranged in the vertical direction and includes a recording head 24 that discharges droplets in the horizontal direction.

  The recording head 24 has two nozzle rows in which nozzles that eject a plurality of droplets are arranged in a row. One nozzle row of the recording head 24a is a yellow (Y) droplet, the other nozzle row is a magenta (Y) droplet, and one nozzle row of the recording head 24b is a black (K) droplet. The other nozzle row ejects cyan (C) droplets.

  The carriage 23 is mounted with a head tank 29 for supplying ink of each color corresponding to each nozzle row of the recording head 24. Ink is supplied to the head tank 29 from ink cartridges (main tanks) of respective colors that are detachably attached to the apparatus main body.

  The sheets 10 in the sheet feeding tray 4 are separated one by one by a sheet feeding roller (half-moon roller) 43 and a separation pad 44 and fed into the apparatus main body. Then, the sheet is fed along the conveyance guide member 45 between the conveyance belt 51 of the conveyance mechanism unit 5 and the presser roller 48 and is sucked and conveyed by the conveyance belt 51.

  The transport mechanism 5 includes an endless transport belt 51 that is stretched between a transport roller 52 that is a driving roller and a driven roller 53. Further, the transport mechanism unit 5 includes a charging roller 54 for charging the transport belt 51 and a platen member 55 that maintains the flatness of the transport belt 51 at a portion facing the image forming unit 2. .

  The conveyance belt 51 rotates in the belt conveyance direction (sub-scanning direction, paper conveyance direction) when the conveyance roller 52 is rotationally driven by a sub-scanning motor (not shown) via a timing belt and a timing pulley. Further, a portion of the conveyance belt 51 that conveys the paper 10 facing the recording head 24 is referred to as a normal conveyance portion, and a portion that moves in the direction opposite to the normal conveyance portion is referred to as a reverse conveyance portion.

  The paper discharge conveyance unit 6 includes a paper discharge guide member 61, a paper discharge conveyance roller 62 and a spur 63, a paper discharge conveyance roller 66 and a spur 673, and a paper discharge roller 64 and a spur 65. Then, the sheet 10 on which the image is formed is discharged face down on the sheet discharge tray 7 from between the sheet discharge roller 64 and the spur 65.

  The reversing unit 8 reverses the paper 10 partially discharged to the paper discharge tray 7 by the switchback method and feeds the paper 10 between the conveyance belt 51 and the presser roller 48. A claw 81 is provided. The reversing unit 8 includes a reversing guide member 82, a reversing roller 83 and a spur 84 that is a reversing roller, a conveyance auxiliary roller 85 that faces the driven roller 53, and a reverse conveying portion of the conveying belt 51. Further, a detour guide member 86 that guides the sheet 10 separated from the reverse conveyance portion of the conveyance belt 51 between the conveyance belt 51 and the pressing roller 48 by detouring the charging roller 54 is provided.

  In this image forming apparatus configured as described above, the paper 10 is separated and fed from the paper feed tray 4 one by one, and the paper 10 is electrostatically attracted to the charged transport belt 51, and the transport belt 51 is moved by the circular movement. The paper 10 is conveyed in the vertical direction. Therefore, by driving the recording head 24 according to the image signal while moving the carriage 23, ink droplets are ejected onto the stopped paper 10 to record one line, and after the paper 10 is conveyed by a predetermined amount, The next line is recorded, and the sheet 10 for which recording has been completed is discharged to the discharge tray 7.

  In the case of performing duplex printing, the first surface printing performs the operation as described above, and when the rear end of the paper 10 passes through the reversing part branch (switching claw 81), the paper discharge roller 64 is driven in reverse. The paper 10 is switched back. Then, it is guided to the reverse guide member 82 side, conveyed between the reverse roller 83 and the spur 84, and the paper 10 is fed between the reverse conveyance portion of the conveyance belt 51 and the conveyance auxiliary roller 85.

  As a result, the sheet 10 is attracted to the conveyance belt 51, conveyed by the circular movement of the conveyance belt 51, separated from the conveyance belt 51 on the conveyance roller 52 side, and guided by the detour guide member 86 (via the detour path). ). Then, the second surface printing is performed by feeding again between the normal conveyance portion of the conveyance belt 51 and the pressing roller 48 and sucking the conveyance belt 51 to the image forming area by the recording head 24 again. Then, the paper is discharged onto the paper discharge tray 7.

  Next, a configuration related to maintenance in the present embodiment will be described with reference to FIG. FIG. 3 is an explanatory side view for explaining the movement of the carriage and the maintenance unit of the embodiment.

  First, a maintenance unit 9 that is a maintenance unit that performs maintenance for maintaining and recovering the state of the recording head 24 of the image forming unit 2 is at a position opposite to the transport mechanism unit 5 with the image forming unit 2 interposed therebetween. It is disposed below the image forming unit 2.

  That is, a paper feed tray (paper feed unit) 4 for feeding a recording medium is arranged below the apparatus main body, and a recording medium (paper 10) on which an image is formed by the image forming unit 2 is arranged above the apparatus main body. A paper discharge tray (paper discharge unit) 7 for paper discharge is disposed, and the image forming unit 2 and the maintenance unit 9 are placed in a space surrounded by the paper feed unit 4, the paper discharge unit 7, and the transport mechanism unit 5 serving as a transport unit. The maintenance unit 9 is disposed below the image forming unit 2.

  Here, the maintenance unit 9 includes a cap 91 for capping the nozzle surface 124 of the recording head 24 and a wiper member (wiper blade) 94 for wiping the nozzle surface 124 on the frame 90. Further, a suction pump 97 as a suction means connected to the cap 91, a waste liquid tank 98 connected to the suction pump 97, and the like are provided.

  The carriage 23 on which the recording head 24 of the image forming unit 2 is mounted is an image at a position in FIG. 1 (a position indicated by a broken line in FIG. 3A) at which droplets are ejected from the recording head 24 in the horizontal direction. It is provided so as to be displaceable between the formation position and the maintenance position, which is the position indicated by the solid line in FIGS. 3A and 3B, where the recording head 24 can face the maintenance unit 9.

  Here, since the maintenance unit 9 is disposed below the image forming unit 2, the recording head 24 rotates 90 ° downward from the image forming position, and the position where the nozzle surface 124 faces downward is set as the maintenance position. .

  The rotation of the carriage 23 is performed by transmitting the driving force of a driving motor (not shown) that moves and scans the carriage 23 in the main scanning direction via a clutch mechanism, thereby reducing the number of parts. ing.

  On the other hand, the maintenance unit 9 capping the nozzle surface 124 of the recording head 24 with the cap 91, and the maintenance position shown by the solid line in FIG. 3B and the position in FIG. 1 retracted from the maintenance position (position in FIG. 3A). , And a retreat position which is a position indicated by a broken line in FIG.

  The maintenance unit 9 is moved by transmitting the driving force of a driving motor (not shown) (sub scanning motor) that moves the conveyor belt 51 in the sub scanning direction via a clutch mechanism, thereby reducing the number of parts. doing.

  Next, the movement of the carriage and the maintenance unit during the maintenance operation in the first embodiment will be described.

  When nozzle clogging occurs in the recording head 24 or when the negative pressure in the head tank 29 is not maintained and the meniscus of the nozzle is destroyed, a cleaning operation (maintenance operation) is performed. The cleaning operation is divided into a suction operation, a wiping operation, and an empty ejection operation. The suction operation is performed in the order of capping → ink suction → decap → cap suction.

  First, as shown in FIG. 3A, the carriage 23 rotates approximately 90 degrees in the direction of arrow B from the image forming position shown by the broken line to the maintenance position shown by the solid line, and the nozzle surface 124 moves downward. To do.

  Thereafter, as shown in FIG. 3B, the maintenance unit 9 moves from the retracted position to the maintenance position in an obliquely upward direction in the direction of arrow C, and caps the nozzle surface 124 of the recording head 24 with the cap 91. The maintenance unit 9 may be moved in the horizontal direction and then moved upward in the vertical direction (or vice versa).

  Then, the suction pump 97 is driven to suck a predetermined amount of liquid (ink) from the nozzles of the recording head 24 into the cap 91 and discharge it into the cap 91.

  Thereafter, the maintenance unit 9 moves to a position where the cap 91 is separated (decapped) from the nozzle surface 124 of the recording head 24.

  Then, the suction pump 97 is operated again to suck the residual waste liquid in the cap 91 and discharge it to the waste liquid tank 98.

  Next, the wiper member 94 is moved to a position where the nozzle surface 124 of the recording head 24 can be wiped off, and the nozzle surface 124 is wiped. The wiping direction may be either the vertical direction or the horizontal direction with respect to the nozzle row.

  After wiping, the cap 91 is positioned below the nozzle surface 124 of the recording head 24, and idle ejection is performed from the recording head 24 into the cap 91. After the idle discharge, the suction pump 97 is operated to suck the waste liquid in the cap 91 and discharge it to the waste liquid tank 98.

  Thereafter, the maintenance unit 9 is moved obliquely downward to the retracted position shown in FIG.

  As described above, the maintenance unit 9 is in a space surrounded by the paper feed tray 4, the paper discharge tray 7, and the transport mechanism unit 5, and is opposite to the transport mechanism unit 5 with the image forming unit 2 interposed therebetween (the recording head 24. , The size in the width direction of the apparatus main body can be reduced, and the size can be reduced.

  Further, since the cap 91 of the maintenance unit 9 faces upward, even if the liquid is discharged into the cap 91, it does not leak from the cap 91.

  That is, when the nozzle surface 124 of the recording head 24 is capped and the liquid is discharged into the cap, the waste liquid in the cap drips during decap. Therefore, for example, an air release valve is provided in the cap, and after the liquid in the cap is discharged, the air is released. Thereafter, the waste liquid in the cap is sucked and discharged by the suction pump, and then the decap is performed. Therefore, the structure and operation become complicated, and even if the waste liquid in the cap is sucked and discharged, the residual waste liquid remains and cannot be prevented from dripping completely.

  On the other hand, as described above, inconvenience can be prevented by discharging into the cap with the cap 91 facing upward as in the present embodiment.

  Next, an image forming apparatus according to a second embodiment of the present invention will be described with reference to FIGS. FIG. 4 is a side view of the mechanism of the image forming apparatus, and FIG. 5 is a perspective view of the transport belt.

  When the maintenance unit 9 is arranged on the side opposite to the ejection direction with respect to the recording head 24 as in the first embodiment described above, it is necessary to interrupt the recording operation in order to perform idle ejection during the recording operation.

  Therefore, in the present embodiment, holes (openings) 58 having a width and a height corresponding to the nozzle rows of the recording head 24 are formed in the transport belt 51. In this case, the number of the openings 58 may be one or plural, but it is preferable to reduce the number of holes and provide the holes in the center in order to easily charge the conveying belt 51 and increase the conveying force.

  In the conveying belt 51, an absorbing member 59 that receives the empty ejected droplets is provided at a position facing the opening 58.

  As a result, the idle discharge operation performed before printing and the idle discharge operation performed after printing can be performed within the width of the conveying means, so that an empty discharge receiving portion is not required outside the width of the conveying means. The width size can be further reduced, and the apparatus can be miniaturized.

  Next, an image forming apparatus according to a third embodiment of the present invention will be described with reference to FIG. FIG. 6 is an explanatory side view of a mechanism portion of the image forming apparatus.

  In the present embodiment, a supply unit 200 that supplies liquid (ink) to the head tank 29 of the image forming unit 2 is disposed above the maintenance unit 9 and below the paper discharge tray 7. In relation to the image forming unit 2, the supply unit 200 is disposed on the back side of the image forming unit 2.

  The supply unit 200 includes a replaceable liquid cartridge 201, and a liquid feed pump 202 that feeds liquid back and forth between the liquid cartridge 201 and the head tank 29, and the liquid feed pump 202 is connected to the head via a tube 203. A tank 29 is connected. The supply unit 200 is arranged to be movable in the vertical direction.

  A part of the paper discharge tray 7 is an opening / closing part 71 that can be opened and closed in the direction of arrow D in order to replace the liquid cartridge 201 from above the apparatus main body.

  Next, cartridge replacement in this embodiment will be described with reference to FIG. FIG. 7 is an explanatory side view for explaining the same.

  As shown in FIG. 7A, the opening / closing part 71 of the paper discharge tray 7 is opened in the direction of arrow D. Then, as shown in FIG. 7B, the supply unit 200 is raised in the direction of arrow E to the position shown by the solid line. In this state, the liquid cartridge 201 is inserted / removed in the direction of arrow F through the opening 72 of the paper discharge tray 7 to replace the liquid cartridge 201.

  In the present embodiment, the replacement of the liquid cartridge 201 is performed from the upper side of the apparatus, but it may be performed from the side or the rear side of the apparatus.

  As described above, by arranging the supply unit 200 above the maintenance unit 9 and below the paper discharge tray 7, the width of the apparatus main body can be further reduced, and the apparatus can be downsized.

  Next, an image forming apparatus according to a fourth embodiment of the present invention will be described with reference to FIG. FIG. 8 is an explanatory side view of a mechanism portion of the image forming apparatus.

  In the present embodiment, the supply units 200 are arranged on the side (horizontal direction side) of the maintenance unit 9 and arranged on the opposite side via the image forming unit 2 and the maintenance unit 9. Here, the supply unit 200 is disposed below the height of the bottom of the recording head 24 in the vertical direction.

  Thus, by disposing the supply unit 200 below the recording head 24, the negative pressure in the head tank 29 for forming the meniscus of the nozzles of the recording head 24 can be reduced between the supply unit 200 and the head tank 29. Can be done with water head difference.

  Thereby, since a supply pump etc. become unnecessary, a number of parts can be reduced and it can reduce in size. Of course, a supply pump can be provided.

  Here, in the present embodiment, during the maintenance operation, as shown in FIG. 9A, the carriage 23 rotates in the arrow B direction, and as shown in FIG. 9B, the maintenance unit 9 moves in the arrow G direction. Move up. In FIG. 9, the supply tube is not shown.

  Further, in the present embodiment, the liquid cartridge is replaced by opening the opening / closing part 71 of the paper discharge tray 7 in the direction of arrow D as shown in FIG. 10A, and as shown in FIG. 200 is raised in the direction of arrow E, and the liquid cartridge 201 is inserted and removed in the direction of arrow F through the opening 72. In addition, illustration of a supply tube is abbreviate | omitted in FIG.

  Next, an image forming apparatus according to a fifth embodiment of the present invention will be described with reference to FIG. FIG. 11 is an explanatory side view of a mechanism portion of the image forming apparatus.

  In the present embodiment, the side surface of the carriage 23 on which the recording head 24 is mounted is rectangular. Here, the configuration of the first embodiment has been described, but the configurations of the other embodiments can also be applied.

  Next, an image forming apparatus according to a sixth embodiment of the present invention will be described with reference to FIG. FIG. 12 is an explanatory side view of the mechanism of the image forming apparatus.

  In this embodiment, the recording head 224 is a line-type head in which a large number of nozzles are arranged over the entire width of the sheet, and four recording heads 224 that discharge droplets of each color are disposed along the sheet conveyance direction.

  Here, the four recording heads 224 are held by a common base member 223, and the common base member 223 has a position indicated by a solid line (image forming position) and a position indicated by a broken line (maintenance position) with the support shaft 221 as a fulcrum. It is arranged to be displaceable between them.

  In this case, the above-described opening for empty ejection in the conveyance belt 51 has an opening shape along the nozzle row of the recording head 224 in a direction orthogonal to the moving direction of the conveyance belt 51. In addition, the maintenance unit 9 includes four caps 91 and a suction pump 97.

  By using the line-type head in this way, the maintenance unit and the supply unit are arranged behind the image forming unit 2 between the paper feed tray 4 and the paper discharge tray 7 while increasing the printing speed. And downsizing.

  Next, an image forming apparatus according to a seventh embodiment of the present invention will be described with reference to FIG. FIG. 13 is a schematic side view of a printing mechanism unit of the image forming apparatus.

  In this image forming apparatus, a printing mechanism unit 311 for forming an image is disposed in the apparatus main body, and a first medium port serving as a paper feed port and a paper discharge port of a recording medium is disposed on the upper part of the device main body. A side opening (second paper supply / discharge port) 305 which is a second medium port serving as a paper supply port and a paper discharge port is also provided on the side portion. Are provided.

  Here, the printing mechanism unit 311 includes an image forming unit 321 as an image forming unit, a transport mechanism unit 322 as a transport unit, and the like.

  In the image forming unit 321, a recording head 334 including a liquid discharge head is mounted on a carriage 333 that is supported by a guide rod 331 and a support member 332 so as to be movable in the main scanning direction (the vertical direction in FIG. 13). The recording head 334 ejects ink droplets of, for example, yellow (Y), magenta (M), cyan (C), and black (K). Note that the image forming unit may include a recording head other than the liquid ejection head.

  Here, the recording head 334 is mounted on the carriage 333 at a required angle (about 45 degrees in this example) in a state in which droplets are ejected obliquely downward.

  The transport mechanism unit 322 includes a platen member 341 that guides the transport of the paper 310 so as to face the recording head 334, an upper transport roller 343 and a spur 344 that constitute the first transport rotating body pair 342 on the upper port 304 side, A side transport roller 346 and a spur 347 constituting the second transport rotating body pair 345 on the side port 305 side are provided.

  A guide member 351 for guiding a sheet is disposed between the upper port 304 and the first transport rotating body pair 342, and a sheet is disposed between the side opening 305 and the second transport rotating body pair 345. A guide member 352 for guiding is disposed.

  At this time, the conveyance path (conveyance path) 350 of the paper 310 is a path indicated by a one-dot chain line.

  Here, the direction in which the sheet is conveyed from the upper port 304 toward the side port 305 is defined as a first conveyance direction X1, and the direction in which the sheet is conveyed from the side port 305 toward the upper port 304 is defined as a second conveyance direction. Let X2. Accordingly, the first transport rotating body pair 342 is disposed on the upstream side of the recording head 334 in the first transport direction X1, and the second transport rotating body pair 345 is disposed on the recording head 334 in the second transport direction X2. Arranged upstream.

  In this image forming apparatus, the paper 310 is fed from the upper port 304, and the paper 310 is transported in the first transport direction X 1 while following the platen member 341 by the transport mechanism unit 322, and the recording head of the image forming unit 321. An image can be formed by ejecting liquid droplets from 334, and the paper 310 can be sent out from the side opening 305.

  Further, the sheet 310 is fed from the side opening 305, and the sheet 310 is conveyed in the second conveying direction X <b> 2 by following the platen member 341 by the conveying mechanism unit 322, and the liquid is discharged from the recording head 334 of the image forming unit 321. An image can be formed by ejecting droplets, and the paper 310 can be sent out from the upper port 304.

  That is, the image forming apparatus according to the present embodiment includes an image forming unit that forms an image on a recording medium, and the recording medium facing the image forming unit, and the first transport direction and the first transport direction are opposite to each other. Transporting means capable of transporting in the second transporting direction, and when the recording medium is fed from one of the transporting means, the image forming means transports the recording medium in the first transporting direction. An image is formed, sent to the other of the conveying means, and when the recording medium is fed from the other conveying means, the image forming means forms the image while conveying the recording medium in the second conveying direction, and is conveyed It is a device that delivers to one of the means.

  A sheet sensor 371 that is a sheet detection unit that detects a sheet near the upper port 304 and a sheet sensor 372 that is a sheet detection unit that detects a sheet near the side port 305 are provided. The paper sensors 371 and 372 can be configured by, for example, photo sensors, but are not limited thereto.

  Next, a configuration related to maintenance in the present embodiment will be described with reference to FIGS. FIG. 14 is a schematic side view for explaining a mechanism portion used for explanation when the maintenance operation is shifted, and FIG. 15 is a schematic side view for explaining a mechanism portion used for explanation during a maintenance operation.

  The carriage 333 is held so as to be rotatable about the guide rod 331. As a result, the carriage 333 of the image forming unit 321 causes the recording head 334 to face the platen member 341 and eject the liquid droplets toward the recording medium (first position: position in FIG. 13). And a maintenance position where the recording head 334 can face the maintenance means 401 (second position: position shown in FIG. 15).

  On the other hand, the maintenance unit 401 is disposed so as to be movable in a direction (arrow direction) that moves forward and backward with respect to the platen member 341 of the transport mechanism unit 322. The maintenance means 401 moves between a retracted position retracted from the carriage 333 shown in FIG. 13 and a maintenance position where the recording head 334 of the carriage 333 shown in FIG. 15 performs a maintenance operation.

  The maintenance unit 401 is disposed at a position that overlaps the recording medium conveyance area by the conveyance mechanism unit 322 when projected toward the conveyance mechanism unit 322 as a conveyance unit.

  Note that a suction platen, a suction belt, or the like may be used as means for holding and transporting the paper 310 that is a recording medium. Further, the means for holding the carriage 333 so as to be movable is not limited to the guide rod 331 but may be a guide rail or the like, and the posture of the carriage 333 can be changed as described above (moving between the first position and the second position). Any configuration is possible.

  Since it comprised in this way, when performing a maintenance operation | movement, the carriage 333 is moved to the maintenance position (position facing the maintenance means 401) in the main scanning direction (reciprocating operation direction).

  Then, as shown in FIG. 14, the maintenance means 401 is allowed to enter by rotating the carriage 333 in the direction of the arrow with the guide rod 331 as the rotation axis by a carriage rotational movement mechanism (means) not shown. .

  Thereafter, as shown in FIG. 14, the maintenance unit 401 is moved in the direction of the arrow to enter below the recording head 334 to be in the maintenance position. Then, as shown in FIG. 15, the carriage 333 is rotated in the direction of the arrow so that the recording head 334 is opposed to the maintenance means 401 and a required maintenance operation is performed.

  The transition from the maintenance state to the printable state is performed in the reverse operation.

  The operation order of the carriage 333 and the maintenance unit 401 when performing the maintenance operation is not limited to the above example.

  For example, after the carriage 333 is rotated to the position shown in FIG. 14, the carriage 333 is moved to the maintenance position in the main scanning direction, and then the maintenance unit 401 is moved to the maintenance position to shift to the maintenance operation in the state shown in FIG. You can also. In short, the order and the number of operations are not limited as long as the carriage 333 and the maintenance unit 401 do not interfere with each other.

  Next, the angle of the recording head 334 will be described. Here, the recording head 334 during printing (image formation) is inclined at about 45 degrees and becomes horizontal during the maintenance operation, but this is not restrictive.

  For example, as described in the above embodiments, an image can be formed in a state where the recording head 334 is inclined by 90 degrees, and the image can be horizontal during a maintenance operation. Further, the recording head 334 during printing (image formation) may be inclined at about 45 degrees, and rotated 90 degrees during the maintenance operation and inclined at 45 degrees in the reverse direction.

  That is, the recording head 334 can move between a first position facing the recording medium and a second position facing the maintenance means and different from the first position during the printing operation and the maintenance operation. If so, the angle of the recording head 334 is not limited.

  The operation of the maintenance means 401 is also configured to move in the horizontal direction here, but it can also be configured to move in a vertical or oblique direction along a linear locus or a curved locus.

  Next, the arrangement of the maintenance unit 401 in the main scanning direction will be described with reference to FIGS. FIG. 16 is a front explanatory view of the mechanism section in a state where the maintenance means is in the retracted position, and FIG. 17 is a front explanatory view of the mechanism section in a state where the maintenance means is in the maintenance position. 16 corresponds to a view of FIG. 13 viewed from the right direction, and FIG. 17 corresponds to a view of FIG. 15 viewed from the right direction.

  First, the mechanism portion will be described. The upper conveyance roller 343 and the side conveyance roller 346 of the conveyance mechanism portion 322 are rotatably held by the left and right side plates 380A and 380B, respectively.

  The transport mechanism 322 includes a motor 381, a motor gear 382 rotated by the motor 381, and an upper transport roller gear 383 and a side transport roller 346 attached to the shaft portion 343a of the upper transport roller 343, which mesh with the motor gear 382, respectively. And a side conveyance roller gear 384 attached to the shaft portion 346a.

  Further, an upper connection gear 385 that meshes with the upper conveyance roller gear 383 and a side connection gear 386 that meshes with the side conveyance roller gear 384 are provided. These connection gears 385 and 386 are for transmitting a driving force to the expansion unit when the expansion unit is connected to the upper port 304 and the side port 305.

  Since the drive train is configured as described above, the upper conveying roller 343 and the side conveying roller 346 are rotated in the same direction by rotating the motor 381.

  As described above, the maintenance unit 401 is arranged at a position overlapping the recording medium conveyance area by the conveyance mechanism unit 322 when projected toward the conveyance mechanism unit 322 as a conveyance unit.

  As a result, the size of the apparatus main body in the width direction can be reduced, and downsizing can be achieved. That is, the size of the apparatus main body in the width direction (carriage reciprocation direction) is determined by the acceleration area and the printing area of the carriage 333 and the transport mechanism. Therefore, by arranging the maintenance unit 401 in the print area (in the transport area) in the main scanning direction, the size in the width direction of the apparatus main body can be reduced.

  In the present embodiment, the empty discharge receiver 390 that receives empty discharged droplets that do not contribute to image formation is provided in the acceleration region of the carriage 333. In other words, printing is not performed during carriage acceleration because the behavior of the carriage 333 is not stable, but droplet ejection accuracy is not required for idle ejection (preliminary ejection). Therefore, idle ejection is performed in this region.

  In this case, when printing is performed in a part of the acceleration region of the carriage 333 to reduce the apparatus main body size, the idle discharge positions are provided on both sides of the transport mechanism unit 322, and the left and right sides of the plurality of nozzle rows are respectively left and right. It is also possible to use properly depending on the discharge position.

Further, when the liquid cartridge as described in the third embodiment is used, when the cartridge mounting portion for mounting the liquid cartridge is projected toward the transport unit, the transport area of the recording medium by the transport unit It is preferable to arrange in an overlapping position. Thereby, the increase in the width direction size of the apparatus main body can be suppressed.

  Next, an eighth embodiment of the present invention will be described with reference to FIG. FIG. 18 is a schematic side view of a mechanism unit in the same embodiment.

  In this embodiment, the carriage 333 and the guide rod 331 are coupled in a key shape. That is, a key portion 331a having a convex shape in a cross section orthogonal to the main scanning direction is formed on the outer periphery of the guide rod 331, and a recess 333a in which the key portion 331a is fitted is formed in the carriage 333.

  Thereby, the carriage 333 can be rotated by rotating the guide rod 331.

  In this case, it is preferable that the portion (bearing portion) of the carriage 333 received by the guide rod 331 is supported by the upper two points 333b1 and 333b2 of the guide rod 331 in order to ensure the accuracy of the carriage 333.

  Further, when the gap adjustment between the recording head 334 and the platen member 341 is performed by the cam shape of the guide rod 331, it is preferable to provide play on the concave portion 333a side in which the key portion 331a of the guide rod 331 is fitted. .

  Next, a ninth embodiment of the present invention will be described with reference to FIGS. FIG. 19 will be described. FIG. 19 is a schematic side view for explaining a mechanism portion used for explanation during the printing operation of the embodiment, and FIG. 20 is a schematic side view for explaining the mechanism portion used for explanation during a maintenance operation. FIG. 21 is an explanatory front view of the mechanism portion used for explaining the printing operation, and FIG. 22 is an explanatory front view of the mechanism portion used for explaining the maintenance operation.

  In the present embodiment, a rotation gear 391 is provided on the side surface in the main scanning direction of the carriage 333. In addition, a drive gear 392 that meshes the rotation gear 391 with the carriage 333 at the second position (position where maintenance is performed) is disposed.

  The drive gear 392 moves to the retracted position retracted from the moving area of the carriage 333 as shown in FIG. 19 during the printing operation, and enters and moves into the moving area of the carriage 333 as shown in FIG. 20 during the maintenance operation. The drive position moves to mesh with the gear 391.

  Therefore, when the maintenance operation of the recording head 334 is performed, the carriage 333 is moved from the state shown in FIGS. 19 and 21 so that the rotation gear 391 of the carriage 333 can be brought into a position in the main scanning direction where the drive gear 392 can be engaged. Thereafter, the drive gear 392 is moved to the drive position and meshed with the rotation gear 391, the drive gear 392 is driven to rotate, and the carriage 333 is rotated in the direction of the arrow to enter the maintenance state.

  In this case, the entering operation of the maintenance means 401 and the raising / lowering rotation operation of the carriage 333 are the same as those described in the seventh embodiment.

  Next, a tenth embodiment of the present invention will be described with reference to FIGS. FIG. 23 is an explanatory side view when the front cover is opened and the carriage is in the print position, and FIG. 24 is an explanatory side view when the front cover is opened and the carriage is in the maintenance position.

  In the present embodiment, the front cover 100 of the apparatus main body can be opened in the direction of the arrow in FIG. 23, and the transport mechanism unit 5 can be similarly opened. Note that portions corresponding to those in the first embodiment are denoted by the same reference numerals and description thereof is omitted. However, a guide stay 122 is used instead of the secondary guide member 22.

  As a result, when a jam occurs, as shown in FIGS. 23 and 24, the front cover 100 and the transport mechanism 5 are opened, so that the jam processing can be easily performed.

  In the present application, the “paper” is not limited to paper, but includes OHP, cloth, glass, a substrate, etc., and means a material to which ink droplets or other liquids can be attached. , Recording media, recording paper, recording paper, and the like. In addition, image formation, recording, printing, printing, and printing are all synonymous.

  The “image forming apparatus” means an apparatus that forms an image by discharging a liquid onto a medium such as paper, thread, fiber, fabric, leather, metal, plastic, glass, wood, ceramics or the like. In addition, “image formation” not only applies an image having a meaning such as a character or a figure to a medium but also applies an image having no meaning such as a pattern to the medium (simply applying a droplet to the medium). It also means to land on.

  The “ink” is not limited to an ink unless otherwise specified, but includes any liquid that can form an image, such as a recording liquid, a fixing processing liquid, or a liquid. Used generically. For example, DNA samples, resists, pattern materials, resins and the like are also included.

  In addition, the “image” is not limited to a planar image, and includes an image given to a three-dimensionally formed image and an image formed by three-dimensionally modeling a solid itself.

2 Image forming section 4 Paper feeding section 5 Transport mechanism section 6 Paper discharge transport section 7 Paper discharge tray 8 Reversing section 9 Maintenance unit 10 Paper (recording medium)
23 Carriage 24 Recording head 51 Conveying belt 91 Suction cap 94 Wiper member 124 Nozzle surface 200 Supply unit 201 Liquid cartridge 202 Supply pump 304 Upper port (first medium port)
305 Side port (second medium port)
321 Image forming unit 322 Conveying mechanism unit 333 Carriage 334 Recording head 341 Platen member 342 First conveying rotating body pair 343 Upper conveying roller 344 Spur 345 Second conveying rotating body pair 346 Side conveying roller 347 Spur

Claims (10)

Image forming means including a recording head having a nozzle for discharging droplets;
A conveying means for conveying a recording medium facing the image forming means;
A cap for capping the nozzle surface of the recording head, and maintenance means for maintaining the recording head,
The conveying unit and the maintenance unit are arranged on opposite sides of the image forming unit,
The image forming means is provided so as to be displaceable between an image forming position where the droplets are discharged from the recording head in a horizontal direction and a maintenance position where the recording head can face the maintenance means,
The image forming apparatus according to claim 1, wherein the maintenance unit is provided so as to be movable between a maintenance position where the cap surface of the recording head is capped with the cap and a retracted position retracted from the maintenance position. A paper feeding unit that feeds a recording medium is arranged below the apparatus main body,
A paper discharge unit for discharging the recording medium on which the image is formed by the image forming unit is disposed above the apparatus main body,
The image forming unit and the maintenance unit are disposed in a space surrounded by the paper feeding unit, the paper discharge unit, and the transport unit,
The image forming apparatus according to claim 1, wherein the maintenance unit is disposed below the image forming unit.   The image forming apparatus according to claim 1, wherein the image forming unit is displaced so that a nozzle surface of the recording head faces downward at the maintenance position.   4. The image forming apparatus according to claim 1, wherein a liquid supply unit that supplies liquid to the image forming unit is disposed above a retracted position of the maintenance unit. 5.   A liquid supply unit that supplies liquid to the image forming unit is disposed on the side of the retracting position of the maintenance unit, and the liquid supply unit is located on the opposite side of the maintenance unit from the image forming unit. The image forming apparatus according to claim 1, wherein the image forming apparatus is an image forming apparatus.   6. The maintenance position according to claim 1, wherein the maintenance position and the retraction position of the maintenance means are in an oblique positional relationship when viewed from a direction along a conveyance direction of the recording medium. Image forming apparatus. The transport means includes a transport belt that sucks and transports the recording medium,
The image forming apparatus according to claim 1, wherein an opening is formed in the conveyance belt at a position facing the recording head.   The image forming apparatus according to claim 7, wherein an absorbing member is disposed at a position facing the recording head via the conveyance belt. Image forming means including a recording head having a nozzle for discharging droplets;
A conveying means for conveying a recording medium facing the image forming means;
Maintenance means for performing maintenance of the recording head,
The image forming unit is provided to be displaceable between an image forming position where the droplets are discharged from the recording head toward the recording medium and a maintenance position where the recording head can face the maintenance unit. ,
The image forming apparatus according to claim 1, wherein the maintenance unit is arranged at a position overlapping with a conveyance area of the recording medium by the conveyance unit when projected toward the conveyance unit side. The image forming unit includes a head tank that supplies liquid to the recording head,
Comprising a replaceable liquid cartridge for supplying liquid to the head tank;
10. The apparatus according to claim 9, wherein the cartridge mounting portion for mounting the liquid cartridge is disposed at a position overlapping with a transport area of the recording medium by the transport unit when projected toward the transport unit side. The image forming apparatus described in 1.

Images