JP2009101609A - Image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming apparatus capable of efficiently and easily removing mist generated in the image forming apparatus.
An image forming apparatus according to the present invention includes a carriage mounted with a recording head and reciprocatingly moved in a main scanning direction, a conveying means for conveying a recording medium in a sub-scanning direction orthogonal to the main scanning direction, and a recording medium recorded It has a recording medium support means that supports the head at a position facing the head, and an empty discharge receiving portion that receives the recording liquid discharged in the empty discharge operation for discharging droplets that do not contribute to image formation from the recording head. The image forming apparatus according to the present invention includes an air flow generating unit that sucks the liquid droplets discharged into the idle discharge receiving portion, and an air outlet provided in the recording medium support unit for the liquid droplets sucked by the air flow generating unit. And a droplet path that leads to the back surface of the recording medium.
[Selection] Figure 5

Description

  The present invention relates to an image forming apparatus, and more particularly to a technique for eliminating recording liquid particles (mist) generated during image formation.

  As an image forming apparatus such as a printer, a facsimile machine, a copying machine, or a multifunction machine of these, for example, a recording head composed of a liquid discharge head for discharging a recording liquid (liquid) droplet is provided as an image forming means, and a recording medium such as paper Alternatively, there is a type in which an image is formed by adhering a recording liquid as a liquid to the medium while conveying a medium such as a recording medium. The image forming apparatus means an apparatus that forms an image by discharging liquid onto a medium such as paper, thread, fiber, fabric, leather, metal, plastic, glass, wood, ceramics, and the like. In addition to giving an image having a meaning such as a character or a figure to a medium, it also means giving an image having no meaning such as a pattern to the medium. The liquid is not limited to the recording liquid and the ink, and is not particularly limited as long as it is a liquid capable of forming an image.

  As such an image forming apparatus, a liquid discharge head as an image forming unit is mounted on a carriage, the liquid discharge head is moved and scanned in the main scanning direction, and the medium is moved intermittently in the sub-scanning direction orthogonal to the main scanning direction. In addition, there is known a serial type image forming apparatus that forms an image by ejecting liquid droplets from a liquid ejection head.

  In such a serial type image forming apparatus, a maintenance / recovery mechanism is provided to maintain and recover the state of the recording head. As the maintenance and recovery mechanism, for example, a moisturizing cap for capping the nozzle surface on which the nozzles of the recording head are formed or a cap member for both suction and moisturizing, and a wiper as a cleaning member for cleaning the nozzle surface of the recording head It has a blade.

  In addition, even if the nozzle surface is capped to prevent drying, if it is left without being discharged or sucked for a long time, the recording liquid in the nozzle dries and thickens, causing a discharge failure. Also, before entering the image forming operation, a recording liquid that does not contribute to image formation, which is referred to as an idle ejection operation, is performed, and an empty ejection receiving member that receives the ejected recording liquid is also provided.

  By the way, when such an idle ejection operation is performed, minute recording liquid particles called mist are generated, and if the recording liquid particles adhere to the head surface, there is a problem of poor printing due to color mixing or non-ejection. Further, when the recording liquid particles are scattered inside the apparatus main body and adhere to an optical encoder used for drive control of a carriage or the like, it may cause erroneous detection and malfunction. Further, the mist discharged to the idle discharge receiving member may flow back into the apparatus main body due to the negative pressure generated by the movement of the carriage after the idle discharge operation.

Therefore, it is desirable to collect or eliminate mist floating in the apparatus main body. Conventionally, as described in Patent Document 1, for example, a fan motor provided for heat dissipation of electronic components can be used for suction of mist in the apparatus main body and discharge to the outside of the apparatus main body. The thing which aimed at is known.
JP 2000-2111163 A

  However, according to Patent Document 1, the mist discharged to the outside of the apparatus main body contaminates the wall in the vicinity of the discharge port, and the mist filter is provided to reduce the amount of mist discharged to the outside of the apparatus main body. However, the filter is easily clogged, and it was necessary to replace it regularly.

  SUMMARY An advantage of some aspects of the invention is that it provides an image forming apparatus that can efficiently and easily remove mist generated in the image forming apparatus.

  In order to solve the above problems, an image forming apparatus according to the present invention includes a carriage mounted with a recording head and reciprocatingly moved in a main scanning direction, and a conveying unit that conveys a recording medium in a sub-scanning direction orthogonal to the main scanning direction. A recording medium supporting means for supporting the recording medium at a position facing the recording head, and an empty discharge receiving portion for receiving the recording liquid discharged in the empty discharging operation for discharging droplets that do not contribute to image formation from the recording head. ing. The image forming apparatus according to the present invention includes an air flow generating unit that sucks the liquid droplets discharged into the idle discharge receiving portion, and an air outlet provided in the recording medium support unit for the liquid droplets sucked by the air flow generating unit. And a droplet path that leads to the back surface of the recording medium via the recording medium. Therefore, the mist generated immediately above the idle discharge receiving portion can be efficiently guided to the inside of the empty discharge receiving portion, and the backflow of the mist due to the negative pressure when the carriage moves can be prevented. Further, since the sucked mist is guided to the back surface of the recording medium and sprayed to be discharged out of the main body of the apparatus, there is no need to periodically collect and remove the sucked mist. Further, since the amount of mist sprayed on the back surface of the recording medium is very small, the quality is not affected.

  Further, the recording medium holding member for pressing the recording medium to the recording medium supporting means is provided, and the air outlet is provided immediately below the recording medium holding member, thereby preventing the recording medium from being lifted by the air flow. Can be discharged efficiently.

  Further, by providing the air outlet at a position avoiding the end of the recording medium in the main scanning direction, the mist can be efficiently discharged while preventing the recording medium main scanning direction end from being lifted by the air flow.

  According to the image forming apparatus of the present invention, the liquid droplets discharged into the idle discharge receiving portion by the air flow generation unit are sucked, and the liquid droplets sucked through the droplet path are passed through the outlet provided in the recording medium support unit. To the back of the recording medium. Therefore, the mist generated in the image forming apparatus can be removed efficiently and easily.

  FIG. 1 is a perspective view showing the configuration of the image forming apparatus of the present invention. The image forming apparatus according to the present invention shown in the figure includes a droplet discharge device including a maintenance / recovery device. The image forming apparatus of the present invention stocks an apparatus main body 10, a paper feed tray 11 for loading paper loaded on the apparatus main body 10, and paper on which an image is recorded (formed) mounted on the apparatus main body 10. The paper discharge tray 12 is provided. Furthermore, one end of the front surface 13 of the apparatus main body 10 has a cartridge loading portion 15 that protrudes forward from the front surface 13 and is lower than the upper surface 14. On the upper surface of the cartridge loading portion 15, operation keys and display are provided. An operation unit 16 such as a vessel is arranged. The cartridge loading unit 15 has a front cover 18 that is replaceably mounted with an ink cartridge 17 that is a main tank for storing liquid as a liquid replenishing unit.

  FIG. 2 is a schematic sectional view showing the overall configuration of the image forming apparatus of the present invention. FIG. 3 is a schematic plan view showing the main configuration of the image forming apparatus of the present invention. As shown in both figures, the image forming apparatus of the present invention slides the carriage 22 in the main scanning direction by a guide rod 20 and a stay 21 which are guide members horizontally mounted on the left and right side plates 19a and 19b constituting the frame 19. It is held movably and moved and scanned in the direction indicated by the arrow in FIG. 3 (carriage scanning direction: main scanning direction) by a main scanning motor (not shown). In the carriage 22, a plurality of recording heads 23, which are ink jet heads that are droplet discharge heads for discharging recording liquid droplets (ink droplets), are arranged in a direction crossing a plurality of nozzles in the main scanning direction. The ink droplet ejection direction is directed downward.

  Here, the recording head 23 includes, for example, a recording head 23y that discharges yellow (Y) droplets, a recording head 23m that discharges magenta (M) droplets, and a recording head 23c that discharges cyan (C) droplets. The recording head 23bk ejects black (Bk) droplets.

  Note that the color is not distinguished when the recording head 23 is referred to. In addition, the head configuration is not limited to these examples, and it may be configured using one or a plurality of recording heads having one or a plurality of nozzle rows that eject droplets of one or a plurality of colors. Also, the arrangement order can be freely arranged. Further, as the droplet discharge head constituting the recording head 23, a piezoelectric actuator such as a piezoelectric element, a thermal actuator that uses a phase change due to liquid film boiling using an electrothermal transducer such as a heating resistor, and a temperature change A shape memory alloy actuator using a metal phase change, an electrostatic actuator using an electrostatic force, or the like provided as pressure generating means for discharging droplets can be used.

  Also, the carriage 22 is equipped with sub tanks 24y, 24m, 24c, and 24bk for each color for supplying the recording liquids of the respective colors to the recording heads 23 (referred to as sub tanks 24 when colors are not distinguished). The sub tank 24 is supplied with the recording liquid from the ink cartridges 17 of the respective colors (referred to as ink cartridges 17y, 17m, 17c, and 17bk in the case of distinguishing each color) through the recording liquid supply tubes 25 of the respective colors. I have to.

  In addition, the sub tank 24 has an ink end sensor (not shown) using a detection electrode for detecting that the amount of ink (recording liquid) contained in the sub tank 24 is less than or equal to a predetermined amount (ie, ink end). In this case, the recording liquid of the corresponding color is replenished and supplied from the corresponding ink cartridge 17 and the replenishing and supplying operation from the ink cartridge 17 is performed. When the ink end state is not resolved, the ink cartridge 17 is also assumed to have reached the ink end and performs the required processing. The “no recording liquid” state in the present invention corresponds to a state in which the ink cartridge 17 is in an ink end. The ink end state includes an ink near end state.

  On the other hand, as a paper feeding unit for feeding the paper 27 stacked on the paper stacking unit (bottom plate) 26 of the paper feed tray 11, feeding of the half-moon roller that separates and feeds the paper 27 one by one from the paper stacking unit 26. A separation pad 29 made of a material having a large friction coefficient is provided facing the paper roller 28 and the paper supply roller 28, and the separation pad 29 is biased toward the paper supply roller 28.

  As a transport unit for transporting the paper 27 fed from the paper feed unit on the lower side of the recording head 23, a transport roller 30 for transporting the paper 29 by electrostatic adsorption and a paper feed unit A counter roller 32 for transporting the paper 27 fed through the guide 31 while sandwiching it between the transport rollers 30 and a paper 29 fed substantially vertically upward are turned approximately 90 ° and copied onto the guide member 33. A conveying guide 34 for adjusting the pressure and a tip pressing roller 36 urged toward the conveying roller 30 by a pressing member 35.

  Further, as a paper discharge unit for discharging the paper 27 recorded by the recording head 23, a paper discharge roller 37 and a paper discharge roller 38 are provided, and a paper discharge tray 12 is provided below the paper discharge roller 37. . Here, the height from the sheet discharge roller 37 and the sheet discharge roller 38 to the sheet discharge tray 12 is increased to some extent to increase the amount that can be stored in the sheet discharge tray 12.

  Further, a double-sided paper feeding unit 39 is detachably mounted on the back surface of the apparatus main body 10. This double-sided paper feeding unit 39 takes in the paper 27 returned by the reverse rotation of the transport roller 30 and reverses it, and feeds it again between the counter roller 32 and the transport roller 30. A manual paper feed unit 40 is provided on the upper surface of the double-sided paper feed unit 39.

  As shown in FIG. 3, a maintenance / recovery device 50 for maintaining and recovering the state of the nozzles of the recording head 23 is disposed in a non-printing area on one side of the carriage 22 in the scanning direction.

  The maintenance / recovery device 50 includes cap members 51a to 51d for capping each nozzle surface of the recording head 22 (referred to as cap member 51 when not distinguished) and a blade member for wiping the nozzle surface. The wiper blade 52 is integrally formed with a wiper blade 52 and a blank discharge receptacle 53 for receiving a droplet when performing a blank discharge for discharging a droplet that does not contribute to recording in order to discharge the thickened recording liquid. A wiper cleaner 54, which is a cleaning member for removing the recording liquid adhering to the wiper blade 52, and a cleaner roller 56 constituting cleaner means for pressing the wiper blade 52 toward the wiper cleaner 54 when the wiper blade 52 is cleaned are provided. .

  Further, as shown in FIG. 3, in the non-printing area on the other side in the scanning direction of the carriage 22, idle ejection for ejecting liquid droplets that do not contribute to recording in order to discharge the recording liquid thickened during recording or the like is performed. An empty discharge receiving portion 57 for receiving droplets when performing the operation is disposed, and the empty discharge receiving portion 57 is provided with an opening 58 along the nozzle row direction of the recording head 23.

  In the liquid ejecting apparatus having such a configuration, the paper 27 is separated and fed one by one from the paper feed tray 11, and the paper 27 fed substantially vertically upward is guided by the guide 31, and includes the transport roller 30 and the counter. It is sandwiched between the rollers 32 and conveyed, and further, the leading end is guided by the conveying guide 34 and pressed against the conveying roller 30 by the tip pressing roller 36, and the conveying direction is changed by approximately 90 °.

  The paper 27 is transported in the sub-scanning direction by the transport roller 30 and the recording head 23 is driven according to the image signal while moving the carriage 22, thereby ejecting ink droplets onto the stopped paper 27. The line is recorded, and after the sheet 27 is conveyed by a predetermined amount, the next line is recorded. Upon receiving a recording end signal or a signal indicating that the trailing edge of the paper 27 has reached the recording area, the recording operation is terminated and the paper 27 is discharged onto the paper discharge tray 12.

  During printing (recording) standby, the carriage 22 is moved to the maintenance / recovery device 50 side, the recording head 23 is capped by the cap member 51, and the nozzles are kept in a wet state to prevent ejection failure due to ink drying. To do. Further, a recovery operation is performed in which the recording liquid is sucked from the nozzle while the recording head 23 is capped by the cap member 51 and the thickened recording liquid and bubbles are discharged. In addition, an idle ejection operation for ejecting ink not related to recording is performed before the start of recording or during recording. Thereby, the stable ejection performance of the recording head 23 is maintained.

  Here, as shown in FIG. 4, a waste liquid tank 59 which is a waste ink storage means generated by the maintenance and recovery operation by the maintenance recovery apparatus 50 is disposed below the maintenance recovery apparatus 50. The discharge side of the tube 62 of the suction pump 61 faces the inlet 60 of the shape. The waste liquid tank 59 is configured not to have an absorber inside, but may be configured to provide an absorber.

  Further, as shown in FIG. 5, during the idle ejection operation, the carriage 22 performs idle ejection immediately above the idle ejection receiving portion 57 through the opening 58 and ejects ink into the idle ejection receiving portion 57. Of the ejected ink, relatively heavy ink accumulates in the absorber 63 provided at the bottom of the idle ejection receiving portion 57. In addition, it is good also as a structure which does not have the absorber 63. FIG. The relatively light ink becomes mist and floats in the air. However, by providing the fan 64 in the idle discharge receiving portion 57, an air flow indicated by an arrow is generated in the empty discharge receiving portion 57, and Mist is sprayed on the back surface of the paper 27 through the droplet path 65 and further through the air outlet 66 provided in the guide member 33. Thus, the paper 27 having the mist sprayed on the back surface is discharged out of the apparatus main body. This eliminates the need for periodically collecting and removing the sucked mist. Further, since the amount of mist sprayed on the back surface of the recording medium is very small, the quality is not affected.

  Note that the fan 64 that is an air flow generating means may be provided in the droplet path 65 instead of in the idle discharge receiving portion 57. Further, the air outlet 66 provided in the guide member 33 is provided at a position avoiding the end portion in the main scanning direction of the recording medium, so that the mist is prevented from floating at the end portion in the main scanning direction of the paper 27 due to the air flow. Can be discharged efficiently. Further, as shown in FIG. 6, by providing the air outlet 66 directly below the recording medium pressing member 35, the mist can be efficiently discharged while preventing the recording medium from floating due to the air flow.

  Further, the present invention is not limited to the above-described embodiment, and it goes without saying that various modifications and substitutions are possible as long as the description is within the scope of the claims.

1 is a perspective view illustrating a configuration of an image forming apparatus of the present invention. 1 is a schematic cross-sectional view showing an overall configuration of an image forming apparatus of the present invention. 1 is a schematic plan view illustrating a configuration of a main part of an image forming apparatus of the present invention. It is a schematic sectional drawing which shows the structure of a maintenance recovery apparatus. It is sectional drawing which shows the structure of the idle discharge receiving part in the maintenance recovery apparatus of this invention. It is sectional drawing which shows another structure of the idle discharge receiving part in the maintenance recovery apparatus of this invention.

Explanation of symbols

57; empty discharge receiving portion, 58; opening, 63; absorber,
64; fan, 65; droplet path, 66; outlet.

Claims (3)

A carriage mounted with a recording head and reciprocatingly moved in the main scanning direction, a conveying means for conveying the recording medium in a sub-scanning direction orthogonal to the main scanning direction, and a recording medium support means for supporting the recording medium at a position facing the recording head And an image forming apparatus having an empty discharge receiving portion that receives a recording liquid discharged in an empty discharge operation of discharging a droplet that does not contribute to image formation from the recording head.
An air flow generating means for sucking the liquid droplets discharged into the empty discharge receiving portion;
An image forming apparatus comprising: a droplet path for guiding droplets sucked by the air flow generating unit to a back surface of the recording medium through an air outlet provided in the recording medium supporting unit.   The image forming apparatus according to claim 1, further comprising a recording medium pressing member that presses the recording medium against the recording medium supporting unit, wherein the air outlet is provided directly below the recording medium pressing member.   The image forming apparatus according to claim 1, wherein the air outlet is provided at a position avoiding an end of the recording medium in the main scanning direction.

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