JP2010052265A - Inkjet recording apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inkjet recording device, in which ink mist generating in margin-less recesses and the ink in the margin-less recesses can be prevented from depositing. <P>SOLUTION: A platen 30, which supports paper P at the position opposite to a recording head 120, is provided with margin-less recesses 30cHP, 30cS and 30cL for receiving the ink discharged, under a condition being jutted out of paper at margin-less recording. In each of the margin-less recess, and ink impacting part 151 for ink to impact thereagainst, is provided. When recording on the paper is executed, the ink impacting part is moved to a first position M, the distance between which and the recording head is smaller; while when no recording is executed, the ink impacting part is moved to a second position N, with the distance between which and the recording head being larger. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an ink jet recording apparatus that performs recording by ejecting ink from a recording head onto a sheet, and more particularly to an ink jet recording apparatus provided in a platen having a blankless recess for receiving ink that has protruded in marginless recording.

  A recording device having functions such as a printer, a copying machine, a facsimile, or a recording device used as an output device of a composite device or workstation including a computer or the like records an image on a sheet by a recording head based on image information. Go. As one form of the recording apparatus, there is an ink jet recording apparatus that performs recording by ejecting ink from a discharge port provided in a recording head onto a sheet. In the recording apparatus, a platen that forms a sheet passing surface for supporting the sheet is disposed at a position facing the recording head. In the case of an ink jet recording apparatus, a distance is required for the ink droplets to fly between the recording head and the paper, and this distance must be managed to an appropriate value in order to land the ink droplets on the correct position on the paper. Is requested.

  In an inkjet recording device, suction is performed by applying a negative pressure to the suction holes arranged on the sheet passing surface of the platen to attract the paper, thereby preventing the paper from lifting and keeping the distance between the recording head and the paper constant. A platen is used. Further, in addition to the normal recording in which margins are provided at the end portions of each side of the paper, recording without margins without margins is also performed. When performing marginless recording, a blankless recess is provided at a position on the platen corresponding to the edge of the sheet so as to receive the ink ejected from the edge. In general, an ink landing portion for landing ink is provided inside the recess without margin. Patent Document 1 describes that the ink landing portion is formed of an ink absorbing material.

In addition, a certain gap is provided between the back surface of the paper and the ink landing portion in order to prevent ink contamination due to contact. However, the ink may accumulate on the ink landing portion, and a phenomenon may occur in which the ink contacts the back surface of the paper. Such a phenomenon is particularly likely to occur when ink with increased viscosity is used to improve color development and color reproducibility. Therefore, Patent Document 2 discloses a configuration that avoids ink accumulation by causing the ink landing portion to be inclined and causing ink to flow out.
Japanese Patent Laid-Open No. 2000-118058 JP 2006-231612 A

  On the other hand, in an ink jet recording apparatus, the greater the distance until ink ejected from a recording head is landed, the greater the amount of ink mist (floating ink), and there is a tendency that ink stains are more likely to occur in the periphery. For this reason, in the structure which inclines the ink landing part of the above-mentioned recessed part without a margin, the distance until ink landed cannot be made small, but the subject that ink mist could not be reduced below fixed occurred.

  The present invention has been made in view of such technical problems. An object of the present invention is to provide an ink jet recording apparatus capable of reducing ink mist generated in a recess without a margin and preventing ink accumulation in the recess without a margin.

  The present invention relates to an ink jetting apparatus that performs recording by ejecting ink from a recording head onto a sheet, and ejects the sheet from the sheet during marginless recording on a platen that supports the sheet at a position facing the recording head. A recess without a margin for receiving ink and an ink landing portion for landing ink on the recess without a margin, and the ink landing portion has a small distance from the recording head when recording on a sheet. When the recording is not performed, the distance from the recording head is large, and the recording head moves to a second position that forms an inclined surface.

  According to the present invention, there is provided an ink jet recording apparatus capable of reducing ink mist generated in a recess without a margin and preventing ink accumulation in the recess without a margin.

  Embodiments of the present invention will be specifically described below with reference to the drawings. Note that the same reference numerals denote the same or corresponding parts throughout the drawings. FIG. 3 is a front perspective view of the ink jet recording apparatus according to the embodiment. FIG. 4 is a rear perspective view of the ink jet recording apparatus according to the embodiment. In FIG. 3 and FIG. 4, the ink jet recording apparatus 10 is instructed on-line / off-line, a command, and the like by various switches and the like disposed on the operation unit 12. A sheet as a recording medium is recorded in the recording apparatus 10 and then discharged from the sheet discharge outlet 14 in the direction of arrow A. An ink tank unit 16 is attached to one end in the width direction of the recording apparatus 10. An openable / closable cover 18 for accessing the inside of the apparatus is attached to the apparatus main body. An insertion port 20 for inserting a sheet is formed on the back surface of the recording apparatus. A paper feed guide 22 for guiding paper to the inside of the apparatus is attached to the insertion slot 20. In the present embodiment, roll paper P wound in a roll shape is used as the paper, and the insertion direction is indicated by an arrow B.

  FIG. 5 is a perspective view of the inside of the ink jet recording apparatus according to the embodiment. 6 is an enlarged perspective view of the platen of FIG. 5 and its peripheral part. Next, with reference to FIG. 3 to FIG. 6, a sheet conveyance path and a recording operation (image formation) process will be described. In the recording apparatus 10, both cut paper having a predetermined size and roll paper wound in a roll shape can be used. Here, a case where the paper is a roll paper P inserted from the insertion opening 20 will be described, but the same applies to a case of a cut paper fed automatically or manually.

  The leading end of the roll paper P is inserted into the insertion slot 20 from the direction of arrow B. The inserted roll paper P is guided by the paper feed guide 22 and fed into the nip between the scanning roller 24 and the pinch roller 28. The pinch roller 28 is pivotally supported by the pinch roller arm 26 and is pressed so as to be driven and rotated by the scanning roller 24. The sheet P is conveyed to the image forming unit 30 a of the platen 30 by the rotation of the scanning roller 24. A large number of suction holes 30b are formed in a predetermined arrangement in the image forming portion 30a of the platen 30. All the suction holes 30b are connected to a suction fan (not shown) through a duct (not shown) formed of a sealed space formed below the platen 30. When recording, the suction fan is operated to suck the paper P on the image forming unit 30a through the suction hole 30b so that the paper P does not float from the image forming unit 30a. After recording, the paper P is further conveyed while being sandwiched between the scanning roller 24 and the pinch roller 28, and is discharged in the direction of arrow A from the paper discharge port 14 on the front surface of the apparatus.

  The recording apparatus is provided with a carriage 40 that reciprocates in the direction of a double arrow C. The carriage 40 includes a head holder 42, and a recording head 44 is detachably attached to the head holder 42. The platen 30 is arranged to support the paper at a position facing the recording head 44. The recording head 44 is an ink jet recording head that performs recording by discharging ink from a discharge port to a sheet based on image information, and there is a predetermined gap (ink droplet flying space) between the recording head 44 and the sheet. Is provided. Ink is supplied from the ink tank unit 16 through the tube 48 to the recording head 44. The recording apparatus 10 can record a color image, and the ink tank unit 16 can supply six colors of ink of black, cyan, magenta, yellow, light cyan, and light magenta. An ink discharge unit for each color is provided. Further, the recording apparatus 10 can perform marginless recording on the edge of the paper. For this reason, the platen 30 is provided with no-margin recesses 30cHP, 30cS, and 30cL for receiving the ink ejected from the paper during the margin-less recording. These blankless recesses are formed in the image forming unit 30a together with a number of suction holes 30b.

  The no-margin recess 30cHP is formed at a position straddling the edge HP on the reference side of the paper P, and receives ink ejected from the one end HP regardless of the width size of the paper. The non-marginless recess 30cS receives ink ejected from the other end of the sheet having a small width, and the non-margin recess 30cL receives ink ejected from the other end of the sheet having a large width. Is. The carriage 40 is supported along the two guide rails 54 so as to be reciprocally movable in the direction of the double arrow C. The carriage 40 is driven by the carriage motor 50 via the belt 52. A linear encoder scale 56 is stretched along the moving direction of the carriage 40 on the apparatus main body. On the other hand, the carriage 40 is equipped with a sensor (not shown) for reading the linear encoder scale 56 using optical or magnetism, thereby detecting the position of the carriage 40.

  The carriage 40 is equipped with a paper end sensor 58 for detecting the end of the paper P supported by the platen 30 in the width direction. As the paper edge sensor 58, for example, a sensor that irradiates the platen 30 with light and determines the presence or absence of the paper P by the reflected light is used. By moving the carriage 40 when the paper P is present, the paper edge sensor 58 detects the paper edge, and the position and width of the paper P are detected from the position of the carriage 40 at this time.

  The sheet P is intermittently conveyed in a direction intersecting with the moving direction of the carriage 40. By temporarily stopping the paper P on the platen 30 and ejecting ink from the recording head 44 while reciprocating the carriage 40, an image of one band on the image forming unit 30a of the paper P is formed. Next, after the sheet P is conveyed by a predetermined distance, an image for the next one band is formed. By repeating such an operation, the entire image is recorded. The recorded paper P is discharged from the paper discharge port 14 while being conveyed by the scanning roller 24 and the pinch roller 28. When the paper is continuous paper such as roll paper, after an image for one page is recorded, the rear end portion is cut with a cutter, and the cut off portion is discharged.

  FIG. 1 is a front sectional view showing a state of a recess without a margin at the time of recording without a margin. FIG. 2 is a front sectional view showing a state of a recess without a margin when recording is not performed. FIG. 7 is a perspective view of the sheet reference side end of the platen. Next, the configuration of the recess without margin will be described by taking the recess without margin on the paper reference side as an example. 6 and 7 indicates the position of the reference side end (or reference surface) of the sheet on the platen 30. The sheet P on the platen 30 is attracted to the sheet passing surface of the platen 30 by the negative pressure suction force acting on the suction hole 30b, and the reference side end portion of the sheet P is located on the recess-less recess 30cHP. The blankless recess at the end opposite to the reference side (non-reference side) of the paper P is symmetrical to the blankless recess 30cHP at the reference end, but the configuration itself is the same. In the present embodiment, a blankless recess 30cL corresponding to a non-reference side edge of a large width sheet and a marginless recess 30cS corresponding to a non-reference side edge of a small width sheet are provided. These blankless recesses 30cL and 30cS are symmetrical to the blankless recess 30cHP described below, but have the same configuration, and their operations and actions are also the same as the blankless recess 30cHP described below. It is.

  In FIG. 1 and FIG. 2, a marginless recess 30cHP has a movable member 102 having an ink landing portion 151 for receiving ink ejected from the end of the paper, and a transmission mechanism for moving the movable member 102. 103. The movable member 102 is rotatably attached to the platen 30 by supporting an inner end portion thereof with a shaft 110. On the upper surface of the movable member 102, an ink landing portion 151 is formed for landing ink ejected from the end of the sheet. The transmission mechanism 103 is disposed below the movable member 102, is supported so as to be movable in the directions of the arrows L and K, and is coupled to the movable member 102 via a coupling portion 153. The movable member 102 is supported in the blankless recess through the elastic member 104a, and the transmission mechanism 103 is supported in the blankless recess through the elastic members 104b and 104c. These elastic members can be composed of rubber-like elastic bodies or spring members.

  A first duct 500 connected to a suction fan (not shown) through an exhaust hole 113 and a second duct 501 (FIG. 10) connected to a suction fan (not shown) through an exhaust hole 114 are configured below the platen 30. Has been. Each suction hole 30 b of the platen 30 communicates with the ducts 500 and 501. The suction fan, ducts 500 and 501, and the suction hole 30b constitute suction means for generating a negative pressure suction force for adsorbing the sheet to the platen 30. One end portion of the transmission member 103 a of the transmission mechanism 103 protrudes into the duct 500 through the through hole 155. For this reason, the transmission mechanism 103 moves into the duct 500 against the elastic force of the elastic members 104b and 104c when the negative pressure suction force in the duct 500 exceeds a certain value (arrow L in FIG. 1). When the value is below a certain value, the elastic members 104b and 104c are returned to the blank-free recess 30cHP by the restoring force (arrow K in FIG. 2).

  In the case of recording without margins in FIG. 1, the recording head 44 records the end portion of the paper P adsorbed on the platen 30. Air in the ducts 500 and 501 is exhausted from the exhaust holes 113 and 114 by a suction fan or the like. At this time, the negative pressure suction force inside the duct 500 where the paper P is present increases. When the suction negative pressure in the duct 500 increases, the transmission mechanism 103 moves in the direction of arrow L, and pushes up the movable member 102 in the direction of arrow F via the support portion 153. As a result, the movable member 102 is rotated to the illustrated horizontal position against the elastic member 104a, and the ink landing portion 151 on the movable member 102 moves to the first position M where the distance from the recording head 44 is small. In the first position M, the ink landing portion 151 is in a suitable posture for landing the ink for recording without margins.

  Next, the state of the blank space-less recess 30cH when recording is not performed will be described with reference to FIG. When recording is not performed or after recording is completed, since there is no sheet on the platen 30, the suction hole 30b is opened, and the negative pressure suction force inside the duct 500 decreases (becomes weak). Therefore, the transmission mechanism 103 is returned in the arrow K direction by the restoring force of the elastic members 104b and 104c. As a result, the support portion 153 is lowered, the movable member 102 is rotated clockwise around the shaft 110 by the restoring force of the elastic member 104a, and the ink landing portion 151 on the movable member 102 is lowered in the arrow J direction. It moves to the second position N where the distance from the recording head 44 is large. In the second position N, the ink landing portion 151 is an inclined surface with the tip lowered. For this reason, the landed ink 101 can be caused to flow out of the ink landing portion 151 by its own weight, be dropped, and discharged from below the marginless recess 30cHP. That is, the second position N is a position for discharging ink.

  FIG. 8 is a front cross-sectional view showing a state in which ink is ejected from the recording head to the concave portion 30cHP without a margin when there is no sheet on the platen 30. FIG. The state of FIG. 8 corresponds to the case where ink not intended for recording is ejected from the recording head 44 to the recess without a margin. For example, the ink fixed to the ink landing portion 151 is fluidized and discharged, or the ink in the ejection port is discharged. This corresponds to preliminary ejection for refreshing ink. Here, the former will be described. In FIG. 8, the ink 101 that has landed on the ink landing portion 151 may become thickened and fixed due to evaporation of moisture or the like when recording is not performed. In that case, in a state where the ink landing portion 151 is in the second position N, the recording head 44 is moved onto the blank space recess 30cHP to discharge ink. As a result, the fixed ink 101 a is fluidized by the ejected ink 108, and can be washed away from the ink landing portion 151 inclined together with the ejected ink 108 and discharged. Further, the ink attached to the ink landing portion 151 can be more easily removed by mechanically wiping the upper surface of the movable member 102 at the inclined second position N.

  FIG. 9 is a plan view of the platen when recording on a wide sheet. FIG. 10 is a front sectional view of the platen when recording on a wide sheet. FIG. 11 is a plan view of the platen when recording on a sheet having a small width. FIG. 12 is a front sectional view of the platen when recording on a sheet having a small width. FIG. 13 is a front sectional view of the platen when recording is not performed. The configuration and operation of a plurality of blankless recesses when the width of the paper P is different will be described with reference to FIGS. 9 to 13. On the platen 30, there is a blankless recess 30cHP at the position of the reference side edge of the sheet, and a blankless recess 30cS at the position of the non-reference side edge of the small width sheet, and the non-reference side edge of the large width sheet. The recessed portions 30cL without margins are respectively provided at the positions. A duct 500 and a duct 501 formed of a sealed space are provided below the platen 30 and at positions corresponding to the gapless recesses, and each duct is provided with a suction (not shown) through the exhaust hole 113 and the exhaust hole 114. Connected to fan. The paper on the platen 30 is sucked by the suction holes 30b formed in a predetermined arrangement and is sucked on the paper passing surface.

  When recording on a sheet having a large width, the suction negative pressure generated inside the sheet reference-side duct 500 and the non-reference-side duct 501 is PH. Then, the ink landing portion 151 rises to the horizontal first position M at the three blankless recesses 30cHP, 30cS, and 30cL. In order to move them to the first position M, a driving force Fc for moving the transmission mechanism 103 of each blankless recess by the negative pressure suction force in each duct is required. Therefore, the strength relationship between the negative pressure suction force PH of the ducts 500 and 501 and the driving force Fc of the transmission mechanism 103 is set so that PH> Fc by the elastic members 104a, 104b, and 104c. This setting can also be performed by adjusting the amount of suction from the duct exhaust holes 113 and 114 with a suction fan (not shown). In this case, the suction negative pressure PH of the duct is, for example, about 500 Pa to 400 Pa. In this way, the transmission mechanism 103 is sucked in each of the recesses without margin, and the ink landing portion 151 is raised and held at the first horizontal position M suitable for landing the ink.

  When recording on a sheet having a small width, the sheet is adsorbed to the platen 30 by the suction hole 30b between the blankless recess 30cHP and the blankless recess 30cS, and the negative pressure suction force inside the duct 500 becomes PH. . On the other hand, since the suction hole 30b is opened in the area where no paper is present, the negative pressure suction force P0 inside the non-reference side duct 501 has a small value. That is, the strength of the negative pressure suction force is PH> P0. The strength of the force Fc for moving the ink landing portion 151 to the first position M is set by the elastic members 104a, 104b, 104c and the like so as to satisfy the relationship PH> Fc> P0. This relationship can also be set by adjusting the amount of suction from the duct exhaust hole 113 or 114 by a suction fan (not shown). In this way, when recording on a sheet having a small width, the transmission mechanism 103 is sucked by the marginless recess 30cHP at the sheet reference side end and the marginless recess 30cS at the non-reference side end of the sheet having a small width. As a result, the ink landing portion 151 is moved to the first position M close to the recording head 44. Further, in the non-margin recess 30cL at the non-reference side end portion of the large width sheet, the ink landing portion 151 remains held at the second position N inclined away from the recording head 120 without moving.

  When recording is not performed, there is no sheet on the platen 30, so that the negative pressure suction force of the ducts 500 and 501 is weak and is equal to or less than P0 regardless of the presence or absence of suction from the exhaust holes 113 and 114. . Accordingly, the transmission mechanism 103 is not sucked in all of the blankless recesses 30cHP, 30cS, and 30cL, and the ink landing portion 151 is held at the inclined ink discharge position (second position) N.

  According to the embodiment described above, a dedicated drive mechanism is not required, and the ink landing portion 151 is close to the recording head 44 with only a concave portion having no margin corresponding to the width of the paper, and is suitable for landing ink. It can be moved to the first position M. At the same time, the ink landing portion 151 can be tilted and moved to the second position N where the ink can be discharged in the recessed portion without margin that is not used. Accordingly, there is provided an ink jet recording apparatus capable of reducing ink mist generated in a recess without a margin at the time of recording without a margin and preventing accumulation of ink in the recess without a margin and capable of recording with high quality without a margin. .

  In the above embodiment, the case where roll paper that is continuous paper is used as an example has been described. However, the present invention may be applied to other forms of paper and paper feeding such as automatic paper feeding or cut paper supplied manually. The same applies to the case of using an apparatus. In addition, the present invention can be similarly applied regardless of the size of the paper, the number of recesses without margins, the number of recording heads, the type and properties of ink used, the material of the paper as a recording medium, and the like.

It is front sectional drawing which shows the state of a recessed part without a margin at the time of recording without a margin. It is front sectional drawing which shows the state of a recessed part without a margin when not recording. 1 is a front perspective view of an ink jet recording apparatus according to an embodiment. 1 is a rear perspective view of an ink jet recording apparatus according to an embodiment. 1 is an internal perspective view of an ink jet recording apparatus according to an embodiment. FIG. 6 is an enlarged perspective view of the platen of FIG. 5 and its peripheral part. It is a perspective view of the paper reference side end of the platen. FIG. 6 is a front cross-sectional view illustrating a state in which ink is ejected from a recording head to a recess without a margin when there is no paper. FIG. 6 is a plan view of a platen when recording on a sheet having a large width. It is a front sectional view of a platen when recording on a sheet having a large width. FIG. 6 is a plan view of a platen when recording on a sheet having a small width. It is a front sectional view of a platen when recording on a sheet having a small width. It is a front sectional view of a platen when recording is not performed.

Explanation of symbols

30 Platen 30b Suction hole 30cHP, 30cS, 30cL No margin concave part 40 Carriage 44 Recording head 102 Movable member 103 Transmission member 104a, 104b, 104c Elastic member 113, 114 Exhaust hole 151 Ink landing part 500, 501 Duct

Claims (6)

In an ink jet recording apparatus that performs recording by discharging ink from a recording head to a sheet, the platen that supports the sheet at a position facing the recording head receives ink discharged from the sheet when the marginless recording is performed. A recess without a margin is provided, and an ink landing portion for landing ink is provided in the recess without a margin,
The ink landing portion moves to a first position where the distance from the recording head is small when recording on a sheet, and is a second position where the distance from the recording head is large and forms an inclined surface when recording is not performed. An ink jet recording apparatus.   The ink jet recording apparatus according to claim 1, wherein the ink landed on the ink landing portion is discharged from the inclined surface when recording is not performed.   The ink jet recording apparatus according to claim 2, wherein the ink landed on the ink landing portion is discharged from the inclined surface together with the ink ejected from the recording head and landed when recording is not performed.   A suction means for generating a negative pressure suction force for adsorbing a sheet to the platen; and a transmission mechanism for moving the ink landing portion according to the strength of the negative pressure suction force. The inkjet recording apparatus according to any one of claims 1 to 3.   The transmission mechanism moves the ink landing portion to the first position when a sheet is present on the platen, and moves the ink landing portion to the second position when there is no sheet on the platen. The inkjet recording apparatus according to claim 4, wherein the inkjet recording apparatus is moved.   The transmission mechanism is held in the second position by an elastic member when no paper is present on the platen, and resists the elastic member by the negative pressure suction force when the paper is present on the platen. The inkjet recording apparatus according to claim 5, wherein the transmission mechanism is moved to the first position.

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