JP5110023B2 - Liquid discharge line head and liquid discharge apparatus - Google Patents

Description

  The present invention relates to a liquid discharge line head including a platen disposed at a position facing a nozzle surface, and a liquid discharge apparatus.

  A conventional general liquid ejecting apparatus such as a printer, a facsimile machine or a copying apparatus incorporates a liquid ejecting head having a plurality of nozzles for ejecting liquid, and a plurality of nozzles in the liquid ejecting head are formed. A discharge target (paper or the like) is transported to a region facing the nozzle surface by a transport device, and liquid is discharged from the nozzle to the discharge target. For this reason, a platen on which the discharge target is placed is disposed at a position facing the nozzle surface, and the distance between the nozzle surface and the discharge target is appropriately held by the platen. Further, a conventional general liquid discharge apparatus is provided with a cleaning mechanism for cleaning the nozzles in order to maintain the discharge performance of the liquid discharge head. The cleaning mechanism includes “a flushing mechanism that continuously ejects ink from each nozzle”, “a suction mechanism that forcibly sucks ink from the nozzles”, and “a wiping mechanism that wipes ink adhering to the nozzle surface of the liquid ejection head” However, even when any of these mechanisms is employed, a part of the mechanism (cap, wiper, etc.) must be disposed at a position facing the nozzle surface. In such a liquid discharge head that is fixedly disposed so as to face the platen, the platen may become an obstacle when cleaning the nozzle.

  Therefore, conventionally, as described in Patent Document 1, the platen is configured to be movable, and when the drive device is attached to the apparatus main body (casing or the like) and cleaning is performed, the platen is moved by the drive device. By doing so, the platen is retracted from the position facing the nozzle surface.

JP 2004-142280 A

  According to the above-described conventional technique (Patent Document 1), the platen can be temporarily retracted from the position facing the nozzle surface, so that the platen can be prevented from becoming an obstacle when cleaning the nozzle. . However, the platen includes a holding member (see FIGS. 13 and 14 of Patent Document 1) attached to the apparatus main body and a support shaft of the drive apparatus attached to the apparatus main body (FIG. 17 and FIG. 18), it is difficult to adjust the position of the nozzle surface and the platen, and it is difficult to properly maintain the distance between the nozzle surface and the discharge target placed on the platen. The above-described prior art (Patent Document 1) has a function of temporarily retracting the platen from the position facing the nozzle surface, but the holding attached to the apparatus main body regardless of the presence or absence of the function. As long as the platen is supported by a member or the like, since many parts are interposed between the nozzle surface and the platen, the position accuracy of the platen with respect to the nozzle surface cannot be increased, and the nozzle surface and the discharge target object It was difficult to maintain the distance properly.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a liquid discharge line head and a liquid discharge apparatus that can appropriately maintain the distance between the nozzle surface and the discharge target. To do.

In order to solve the above-described problems, a liquid discharge line head according to the present invention has a nozzle surface in which a plurality of nozzles that discharge liquid to a discharge target are opened, and the plurality of nozzles in the discharge target A line head main body arranged so as to correspond from one end to the other end in the width direction, a platen arranged to face the nozzle surface and on which the discharge target is placed, and the line head main body And a pair of long side portions extending in the longitudinal direction of the line head body and a pair of short side portions joined at both ends of the pair of long side portions. A plurality of upstream placement pieces provided on one of the pair of long sides, and a plurality of downstream placement pieces provided on the other of the pair of long sides. The plurality of upstream mounting pieces; and Serial plurality of downstream rest piece, said being the exhaust side by side in a straight line in the lateral direction perpendicular to the longitudinal direction of the line head main body, the platen, the plurality of nozzles in the nozzle face formed Configured to be movable between a nozzle facing position facing the nozzle area and a nozzle non-facing position not facing the nozzle area, and when the platen is located at the nozzle facing position, The discharge target is placed on the plurality of upstream placement pieces and the plurality of downstream placement pieces of the platen, and the liquid is discharged from the nozzle, and the platen is attached to the line head body. The mounting portion is pivotally supported by the side end surface of the line head body in the direction in which the nozzle surface extends, and the rotation center of the mounting portion is The side end face is located closer to the nozzle non-opposing position than the center position in the direction parallel to the nozzle face, and the length of the mounting portion is such that the platen is directed from the nozzle facing position to the non-opposing position. when rotating Te, the platen is set at a corner such length as not to contact the of the head, the plurality of upstream rest piece, said plurality of downstream in the direction parallel to the nozzle surface It is located at a position farther from the center of rotation of the mounting portion than the side mounting piece, and further, the end of the plurality of upstream mounting pieces opposite to the plurality of downstream mounting pieces a guide surface inclined away from the nozzle surface moves away from said plurality of downstream rest piece is that is formed.

In this configuration, since the platen is attached to the line head main body via the attachment portion, the number of parts interposed between the line head main body and the platen is reduced, and the position accuracy of the platen with respect to the nozzle surface is increased. be able to.
Further, it is possible to reduce the size of the ink ejection device in which the line head main body is arranged.

In order to solve the above-described problems, a liquid ejection apparatus according to the present invention includes a liquid ejection line head that ejects liquid onto an ejection target, and a transport device that transports the ejection target to the liquid ejection line head. The liquid discharge line head has a nozzle surface in which a plurality of nozzles for discharging liquid are opened, and the plurality of nozzles are arranged so as to correspond from one end to the other end in the width direction of the discharge target. A line head main body, a platen disposed opposite to the nozzle surface, on which a discharge object to be transported by the transport device is placed, and an attachment portion for attaching the platen to the line head main body. The platen has a frame body composed of a pair of long side portions extending in the longitudinal direction of the line head main body and a pair of short side portions joined at both ends of the pair of long side portions;
A plurality of upstream placing pieces provided on one of the pair of long side portions, and a plurality of downstream placing pieces provided on the other of the pair of long side portions, wherein the plurality of upstream sides The placement piece and the plurality of downstream placement pieces are arranged in a straight line in a short direction perpendicular to the longitudinal direction of the line head body, and the platen is arranged on the nozzle surface. It is configured to be movable between a nozzle facing position facing the nozzle area where the nozzle is formed and a nozzle non-facing position not facing the nozzle area, and the platen is located at the nozzle facing position. Sometimes, the discharge object is placed on the plurality of upstream placement pieces and the plurality of downstream placement pieces of the platen, and liquid is discharged from the nozzle, and the platen is placed on the line head body. Through the mounting part The mounting portion is rotatably supported on the side end surface of the line head body in the direction in which the nozzle surface extends, and the rotation center of the mounting portion is on the nozzle surface on the side end surface. It is located on the nozzle non-opposing position side with respect to the central position in a parallel direction, and the length of the mounting portion is set when the platen rotates from the nozzle facing position toward the non-opposing position. The length is set so that the platen does not come into contact with the corner of the head, and the plurality of upstream mounting pieces are mounted in the direction parallel to the nozzle surface than the plurality of downstream mounting pieces. Further, the end opposite to the plurality of downstream mounting pieces among the ends of the plurality of upstream mounting pieces is positioned at a position away from the rotation center of the plurality of downstream mounting pieces. As you move away from the stand, Guide surface inclined away from Le surfaces that are formed.

  This configuration relates to a liquid ejection apparatus including the above-described “liquid ejection line head”.

  The present invention is configured as described above, and since the line head main body, the mounting portion, and the platen are integrated, the number of parts interposed between the line head main body and the platen is reduced, and the nozzle surface It is possible to increase the position accuracy of the platen with respect to. In addition, since the number of the parts is reduced, the entire liquid discharge apparatus incorporating the liquid discharge line head can be reduced in size, and the manufacturing cost can be reduced.

1 is a perspective view illustrating a configuration of an ink ejection device according to an embodiment. It is a front view which shows the structure of the ink discharge apparatus which concerns on embodiment. It is a disassembled perspective view which shows the structure of the ink discharge line head and cap apparatus which concern on embodiment. 2A and 2B are perspective views showing the configuration of the ink discharge line head according to the embodiment from below, in which FIG. 1A is a perspective view showing a state where the platen is located at a nozzle facing position, and FIG. It is a perspective view which shows the state located in the position. It is a fragmentary perspective view which shows the structure of a drive device. It is a partial expansion perspective view which shows the structure of a drive device. FIG. 2 is a front view showing a configuration at “print position”, (A) is a front view showing configurations of an ink discharge line head and a cap device, and (B) is a front view showing a configuration of a drive device. FIG. 3 is a front view showing a configuration at a “cap position”, (A) is a front view showing a configuration of an ink discharge line head and a cap device, and (B) is a front view showing a configuration of a drive device. FIG. 4 is a front view showing a configuration at a “wipe position”, where (A) is a front view showing a configuration of an ink discharge line head and a cap device, and (B) is a front view showing a configuration of a drive device. It is a front view showing a configuration of an ink discharge line head.

  Hereinafter, a “liquid ejection device” according to a preferred embodiment of the present invention will be described with reference to the drawings. Since the “liquid discharge line head” according to a preferred embodiment of the present invention is a component of the “liquid discharge apparatus”, it will be described together with the description of the “liquid discharge apparatus”.

  In the following embodiments, the present invention is applied to an “ink discharge device”. However, the present invention can be applied to a “colored liquid discharge device” that discharges a colored liquid or a “conductive liquid discharge device that discharges a conductive liquid. It is also applicable to other “liquid ejecting apparatuses” such as “ When the present invention is applied to a “colored liquid ejecting apparatus” or “conductive liquid ejecting apparatus”, “ink” used in the following description is read as “colored liquid” or “conductive liquid”. Further, “lower” used in the following description means the direction in which ink is ejected, and “upper” means the opposite direction.

[Overall configuration of ink ejection device]
FIG. 1 is a perspective view illustrating a configuration of an ink discharge apparatus 10 as a “liquid discharge apparatus” according to an embodiment of the present invention, and FIG. 2 is a front view illustrating a configuration of the ink discharge apparatus 10.

  The ink ejection device 10 includes an ink ejection line head 16 as a “liquid ejection line head” having a plurality of nozzles 14 (FIG. 4B) that ejects ink onto a paper 12 as an “ejection target”. A transport device 18 that transports the paper 12 to the ink discharge line head 16, a cap device 20 that covers the plurality of nozzles 14 of the ink discharge line head 16 as necessary, and a platen 22 (described later) of the ink discharge line head 16 (FIG. 3). ) And a drive device 26 for driving a cap main body 24 described later of the cap device 20. In the present embodiment, as shown in FIGS. 1 and 2, a transport path R for transporting the paper 12 is configured by the transport device 18, and the ink discharge line is located at a print position P located in the middle of the transport path R. The head 16 extends in a direction orthogonal to the conveyance direction of the paper 12 and is fixedly disposed. A cap device 20 is disposed at a position facing the plurality of nozzles 14 of the ink discharge line head 16, and a driving device 26 is disposed corresponding to each of the ink discharge line head 16 and the cap device 20. Therefore, in the following, the respective components of the ink ejection device 10 will be described in the order of the transport device 18, the ink ejection line head 16, the cap device 20, and the driving device 26. In the following description, the transport direction of the paper 12 is referred to as “transport direction X”, and the direction orthogonal to the transport direction X is referred to as “line direction Y”.

<Conveyor>
As shown in FIGS. 1 and 2, the conveying device 18 supplies the paper 12 to the printing position P and discharges it from the printing position P. The eight rollers 30 a to 30 h and these rollers 30 a to 30 h And a drive motor (not shown) connected to at least one of the rollers 30a to 30h.

  As shown in FIG. 2, in the transport device 18, the paper is formed by two rollers 30 a and 30 b disposed on the upstream side in the transport direction X from the print position P and a transport belt 32 stretched between them. A paper supply unit 34 for supplying 12 to the printing position P is configured. Further, a sheet discharge unit that discharges the sheet 12 from the print position P by the two rollers 30c and 30d disposed downstream of the print position P in the transport direction X and the transport belt 32 stretched between them. 36 is configured. Rollers 30e and 30f are arranged below the roller 30d located on the most downstream side and the roller 30a located on the most upstream side, respectively. Further, between the roller 30b located upstream of the print position P and the roller 30c located downstream, two rollers 30g and 30h for letting the conveyance belt 32 escape downward from the conveyance path R are the rollers 30b. Thus, a space S for disposing the cap device 20 is formed below the conveyance path R at the print position P.

<Liquid discharge line head>
FIG. 3 is an exploded perspective view showing the configuration of the ink discharge line head 16 and the cap device 20, and FIG. 4 is a perspective view showing the configuration of the ink discharge line head 16 from below.

  The ink discharge line head 16 is fixedly disposed at a print position P (FIGS. 1 and 2) on the transport path R so as to extend in a direction orthogonal to the transport direction X (that is, the line direction Y). 3 and 5, the line head main body 40, the platen 22, and the attachment portion 42 for attaching the platen 22 to the line head main body 40 are provided.

  As shown in FIG. 4, the line head main body 40 has a substantially rectangular parallelepiped head holder 44 extending in the line direction Y and a nozzle plate 46, and the nozzle plate 46 is a lower surface of the head holder 44, i.e., a conveyance. It extends in the line direction Y on the surface facing the sheet 12 (FIGS. 1 and 2) conveyed along the path R. Further, as shown in FIG. 4B, the nozzle plate 46 has a nozzle surface 46a in which a plurality of nozzles 14 for ejecting ink are opened, and a plurality of nozzles 14 are formed on the nozzle surface 46a. The length of the region (hereinafter referred to as “nozzle region”) Q (that is, the length in the line direction Y) is such that the plurality of nozzles 14 can correspond from one end to the other end of the paper 12 in the width direction. It is designed to be approximately the same length as the width of the paper 12 or longer. On the other hand, the width of the nozzle region Q (that is, the length in the transport direction X) is not particularly limited, but in the present embodiment, the nozzle region Q is located at the center of the nozzle surface 46a in the transport direction X. In addition, it is designed to be sufficiently narrower than the width of the nozzle surface 46a.

  Although not shown, on the upper surface of the nozzle plate 46, a flow path unit having a plurality of pressure chambers communicating with each of the plurality of nozzles 14 and a plurality of drives individually corresponding to the plurality of pressure chambers. An actuator having a portion and a wiring board for applying a driving voltage to each drive portion of the actuator are integrally joined, and these components are accommodated in the head holder 44. The wiring board is pulled out from the head holder 44 and connected to the control device, and a drive voltage is applied to the actuator based on the control signal output from the control device. In addition, an ink tank disposed outside the head holder 44 is connected to the flow path unit via an ink tube, and ink sent from the ink tank is supplied to the flow path unit. Yes. The method for ejecting ink from the nozzle 14 is not particularly limited. Instead of the method for ejecting ink using an “actuator”, the ink is ejected using “pressure when heated by a heating element”. A discharge method may be employed. Further, one ink discharge line head 16 may have a plurality of nozzles 14 for each of a plurality of ink colors so that ink of each color is discharged. Furthermore, in the present embodiment, one ink discharge line head 16 is disposed at one print position P, but a plurality of ink discharge line heads 16 may be disposed at a plurality of print positions for each of a plurality of ink colors. Good.

  As shown in FIGS. 3 and 4, mounting portions 42 (FIG. 4), which will be described later, are rotatably supported on both end surfaces 40a of the line head body 40 in the direction in which the nozzle surface 46a extends (that is, the line direction Y). The projection-shaped rotating shaft 48 for positioning, the projection-shaped positioning portion 50 for positioning the mounting portion 42, and one end of the coil spring 52 that biases the mounting portion 42 toward the positioning portion 50 are locked. And a protrusion-like spring locking portion 54a. Note that the positions of the rotary shaft 48, the positioning portion 50, and the spring locking portion 54a are deeply related to the positions of the platen 22 and the attachment portion 42, and will be described later.

  The platen 22 supports the paper 12 at a position facing the nozzle surface 46a of the line head main body 40, thereby appropriately maintaining the distance between the nozzle surface 46a and the paper 12. As shown in FIG. A frame 60 having a substantially rectangular plan view shape extending in the line direction Y (that is, a shape when viewed from above), and a plurality of paper placements formed on the frame 60 at intervals in the line direction Y Part 62.

  As shown in FIG. 3, the frame 60 includes a pair of long side portions 64 a and 64 b that are formed to extend in the line direction Y at intervals in the transport direction X, and a pair of long side portions 64 a and 64 b. It has a pair of short side portions 66a and 66b joined at both ends in the direction Y, and between the pair of long side portions 64a and 64b, immediately before the so-called “borderless printing” and printing on the paper 12. An opening 68 is formed to allow the ink ejected from the nozzles 14 to escape to the side opposite to the nozzles 14 during “preliminary ejection”. Note that the “preliminary ejection” is not limited to ejecting ink from the nozzles 14 immediately before printing on the paper 12, and may perform only ink ejection without transporting the paper 12.

  As shown in FIG. 3, each of the plurality of paper placement units 62 is a portion on which the paper 12 is placed at the print position P (FIGS. 1 and 2), and is upstream of the conveyance direction X in the frame 60. The upstream side mounting piece 62a formed integrally with the long piece portion 64a located at the downstream side, and the downstream side mounting piece 62b formed integrally with the long piece portion 64b located on the downstream side, The side placement pieces 62a and the downstream placement pieces 62b are arranged in a straight line in the transport direction X, and these upper surfaces serve as “paper placement surfaces” for placing the paper 12 thereon. ing. In addition, a gap G having a width that is sufficiently wider than the width of the nozzle region Q (FIG. 4B) is secured between the upstream mounting piece 62a and the downstream mounting piece 62b. Thus, the function of the opening 68 (that is, the borderless printing function) can be effectively exhibited. Then, an end portion of the platen 22 located on the upstream side in the conveying direction X, that is, an upstream end portion of each of the plurality of upstream mounting pieces 62a is inclined so as to move away from the nozzle surface 46a toward the upstream side. A guide surface 70 is formed so as to prevent the paper 12 from being caught on the platen 22 and to smoothly supply the paper 12 to the printing position P. That is, in the present embodiment, the line head main body 40 and the platen 22 are integrally formed, and therefore the height of the “paper placement surface” of the platen 22 is set to the paper supply unit 34 (FIG. 2) in the conveyor belt 32. It is difficult to match the height of the upper surface of the paper, and there is a possibility that a level difference will occur between them. However, the paper 12 can be guided by the guide surface 70 even at the level difference, so the paper 12 with respect to the platen 22 Can be prevented and paper jams can be prevented. Furthermore, each of the pair of short side portions 66a and 66b is formed with a projecting action portion 72 on which power of a driving device 26 described later acts.

  The attachment portion 42 is for pivotally supporting the platen 22 with respect to the line head main body 40, and as shown in FIG. 3, the two attachment portions 42 are formed integrally with the platen 22. That is, as shown in FIG. 4, each of the two attachment portions 42 is a member that connects the platen 22 and the line head body 40, and one end portion of each attachment member 42 is connected to the short side portions 66a and 66b. A bearing hole 76 is formed at the other end of each mounting member 42 so as to be rotatably fitted to the rotation shaft 48 of the line head main body 40. Further, at one end of each mounting portion 42, a contact portion (in this embodiment, a part of the side edge of the mounting portion 42) 78 that is in contact with the positioning portion 50 of the line head main body 40, and the above-described portion. A projection-shaped spring locking portion 54b that is locked to the other end of the coil spring 52 is formed. Then, these two attachment portions 42 are respectively connected to both end surfaces 40a of the line head main body 40 in the extending direction of the nozzle surface 46a (that is, the line direction Y) via a fitting structure of the rotating shaft 48 and the bearing hole 76. It is rotatably supported.

  Here, the platen 22 (FIG. 4) is pivotally supported with respect to the line head main body 40 via the mounting portion 42, thereby opposing the nozzle region Q in which the plurality of nozzles 14 are formed on the nozzle surface 46a. Between the facing position T1 (FIG. 4 (A)) and the nozzle non-facing position T2 (FIG. 4 (B)) that does not face the nozzle region Q, the direction in which the nozzle surface 46a extends (ie, the line direction Y). It is possible to move in an orthogonal direction (that is, the transport direction X). Further, the distance between the nozzle surface 46 a at the nozzle facing position T <b> 1 and the upper surfaces (that is, the paper placement surfaces) of the plurality of paper placement portions 62 is defined by the length of the attachment portion 42. Therefore, in order to shorten the distance between the nozzle surface 46a and the paper placement surface in order to reduce the size of the ink ejection device 10 and improve the image quality, the length of the mounting portion 42 may be shortened. However, when the length of the attachment portion 42 is shortened, the downstream corner portion E located at the lower end portion of the line head main body 40 when the platen 22 moves from the nozzle facing position T1 to the nozzle non-facing position T2. (FIG. 4A) may collide. Therefore, in the present embodiment, as shown in FIG. 7A, the “rotation center” of the mounting portion 42 is a direction parallel to the nozzle surface 46a on the side end surface 40a of the line head body 40 (ie, the transport direction X). The position of the rotary shaft 48 is designed so as to be located on the nozzle non-opposing position T2 side (that is, the downstream side) with respect to the central position W.

  In addition, the nozzle facing position T1 (FIG. 4A), as will be described later, applies ink from the nozzles 14 formed in the nozzle region Q of the line head body 40 to the paper 12 placed on the platen 22. In order to realize the above-described “borderless printing” and “preliminary ejection”, the line is moved when the platen 22 is located at the nozzle facing position T1 (FIG. 4A). The nozzle region Q of the head main body 40 and the opening 68 of the platen 22 need to face each other. Therefore, in this embodiment, in order to achieve the positional relationship, not only the basic configuration of the platen 22 and the mounting portion 42 but also the rotating shaft 48, the positioning portion 50, the spring locking portion 54a, the spring locking portion 54b, The location of details such as the contact 78 is designed.

  According to the ink discharge line head 16 according to the present embodiment, for example, when the platen 22 is removed from the ink discharge device 10 in the case of replacement due to failure, the platen 22 is moved to the nozzle facing position T1 ( 4 (A)), the nozzle surface 46a can be protected by the platen 22.

<Cap device>
As shown in FIG. 3, the cap device 20 includes a cap main body 24 and a cap guide that guides the cap main body 24 when the cap main body 24 moves in the vertical direction (that is, in the direction of approaching or separating from the nozzle surface 46a). 82.

  The cap body 24 includes a nozzle cap 84 and a cap holder 86 that supports the nozzle cap 84, and the nozzle cap 84 and the cap holder 86 are integrated to move up and down in the cap guide 82. It is configured as follows. The basic function of the nozzle cap 84 is to contact the nozzle surface 46a of the line head body 40 and cover the plurality of nozzles 14, and the end portion 84a on the opening side of the nozzle cap 84 damages the nozzle surface 46a. It is made of a material having a cushioning property such as rubber. Moreover, the planar view shape of the said edge part 84a is designed in the substantially rectangular shape extended in the line direction Y so that the nozzle area | region Q (FIG.4 (B)) can be covered. Further, the nozzle cap 84 has a suction function (not shown) for forcibly sucking ink. Further, on both end faces in the line direction Y of the cap holder 86, projecting action portions 88 on which the power of the driving device 26 described later acts are formed.

<Drive device>
The driving device 26 has a function of moving the platen 22 of the ink discharge line head 16 between the nozzle facing position T1 (FIG. 4A) and the nozzle non-facing position T2 (FIG. 4B), and a cap device. 20 cap bodies 24 between a cap position U1 (FIG. 8A) close to the nozzle surface 46a and a standby position U2 (FIGS. 7A and 9A) spaced from the nozzle surface 46a. 5 and FIG. 6, the substantially circular plate-like cam 90, the substantially triangular plate-like slide cam 92, and the slide guide for guiding the slide cam 92 are provided. 94, and a gear unit 96 for rotating the cam 90. Each of the cam 90, the slide cam 92, and the slide guide 94 is disposed symmetrically on both sides of the ink discharge line head 16 in the line direction Y.

  As shown in FIG. 5, the cam 90 has a substantially disc-shaped cam main body 100, and the platen 22 of the ink discharge line head 16 is moved to the surface of the cam main body 100 on the ink discharge line head 16 side. An annular first groove 102 for moving the cap body 20 and an annular second groove 104 for moving the cap body 24 of the cap device 20 are formed in a predetermined shape according to the operations of the platen 22 and the cap body 24. . Further, a gear unit 96 (FIG. 1) having a drive motor is connected to a rotation shaft (not shown) of the cam 90, and the “rotation direction”, “rotation angle” and “ The “stop position” and the like are controlled. An action portion 106 of a slide cam 92, which will be described later, is slidably inserted into the first groove 102, and an action portion 88 of the cap body 24 is slidably inserted into the second groove 104. Thus, power in a predetermined direction is applied to the action portions 106 and 88 according to the “rotation direction” and “rotation angle” of the cam 90, and the action portions 106 and 88 according to the “stop position” of the cam 90. Is supported at a predetermined height.

  The shapes (including the size) of the first groove 102 and the second groove 104 are 3 of “print position (FIG. 7)”, “cap position (FIG. 8)” and “wipe position (FIG. 9)” which will be described later. Designed so that one aspect can be selected. In the process of shifting between these modes, the platen 22 and the cap body 24 are moved simultaneously, but both the first groove 102 and the second groove 104 are formed in the cam body 100 and are applied from the gear unit 96. Therefore, the platen 22 and the cap body 24 do not collide with each other. The above three aspects will be described together in the description of “Operation of Ink Ejecting Device”.

  As shown in FIG. 6, the slide cam 92 has a plate-like cam body 110 having a substantially right triangle, and the oblique side 110 a of the cam body 110 applies power to the action portion 72 of the platen 22. The one side 110b sandwiching the right angle is formed extending in the vertical direction, and the other side 110c sandwiching the right angle is formed extending in the transport direction X. A protrusion 112 guided by a slide guide 94 is formed on the surface of the cam body 110, and a portion above the protrusion 112 on the surface of the cam body 110 is guided by the slide guide 94. In addition, a projecting action portion 106 is formed that is slidably inserted into the first groove 102 of the cam 90. Further, at the end of the cam body 110 on the downstream side in the transport direction X, a protruding support portion 114 that supports the action portion 72 of the platen 22 at the nozzle non-facing position T2 (FIG. 8B) is provided on the other side. It is formed along the extended line of 110c.

  As shown in FIG. 6, the hypotenuse (that is, the drive surface) 110 a of the cam body 110 is formed to be inclined so that the height decreases toward the downstream side in the transport direction X, and the platen 22 is located at the nozzle facing position. When located at T1 (FIG. 7), the action part 72 of the platen 22 is located above the hypotenuse 110a. Therefore, when the slide cam 92 is moved upward by the first groove 102 of the cam 90, the action portion 72 is lifted by the oblique side 110a, and the entire platen 22 is directed to the nozzle non-opposing position T2 (FIGS. 8 and 9). Moved.

  As shown in FIG. 6, the slide guide 94 has a long hole 118 into which the action portion 106 and the protrusion 112 of the slide cam 92 are slidably inserted, and the long hole 118 extends in the vertical direction. Thus, it is fixed to a frame or the like (not shown) of the ink ejection device 10. Therefore, the inclination angle of the hypotenuse 110a is defined by the slide guide 94, and when the slide cam 92 is moved by the cam 90, the driving force is always stabilized at a constant inclination angle with respect to the action portion 72 of the platen 22. Can be granted.

[Operation of ink ejection device]
<Print position>
When a printing operation is performed using the ink discharge apparatus 10, the “print position” shown in FIG. 7 is selected by rotating the cam 90. The “print position” is a mode in which the platen 22 is supported at the nozzle facing position T1 and the nozzle cap 84 is supported at the standby position U2. As shown in FIG. 7B, the slide cam 92 in this embodiment is supported by the first groove 102 of the cam 90 at the lowest position within the moving range, and the cap body 24 is also the second groove 104. Is supported at the lowest position within the moving range. A nozzle cap 84 is disposed immediately below the nozzle surface 46a.

  When the paper 12 is supplied to the print position P (FIGS. 1 and 2) at the “print position”, the paper 12 is supported by the platen 22 of the ink discharge line head 16, and the plurality of nozzles 14 of the line head main body 40. Ink is ejected from the paper 12 to the paper 12. In the present embodiment, since ink can be released from the opening 68 (FIG. 3) formed in the platen 22, so-called “edgeless printing” can be handled. Further, since the opening 68 is formed so as to extend in the longitudinal direction of the platen 22, “edgeless printing” can be performed on the paper 12 of various sizes. In the case of “preliminary ejection” for maintaining or recovering the function of the nozzle 14, the thickened ink, the ink mixed with bubbles, or the like is present in the state where the paper 12 does not exist at the print position P. 14, these inks can escape downward from the opening 68. The ink that has escaped downward from the opening 68 is collected by the nozzle cap 84.

  Further, in the present embodiment, the platen 22 is configured to be movable toward the downstream side in the transport direction X. Therefore, even when the paper 12 is likely to be jammed at the print position P or in the vicinity thereof, the jam is caused. Since the platen 22 is pushed by the loaded paper 12 and moved downstream in the transport direction X, paper jams (ie, jams) can be eliminated in advance. Even when a paper jam (ie, jam) occurs, the jammed paper 12 can be easily removed by moving the platen 22 to the downstream side in the transport direction X.

<Cap position>
When the nozzle area 84 (FIG. 4B) is covered with the nozzle cap 84 when the printing operation is stopped, the cam 90 is rotated clockwise α (FIG. 7B) from the “print position”. The “cap position” shown in FIG. 8 is selected. For example, when a printing operation is not performed, a “cleaning operation” that sucks and removes thickened ink in the nozzle 14 or ink mixed with bubbles by a suction device (not shown), or natural evaporation of ink in the nozzle In the “maintenance operation” in which the nozzle surface is capped to prevent thickening and sticking due to the “cap position”, the “cap position” is selected. The “cap position” is a mode in which the platen 22 is supported at the nozzle non-facing position T2 and the nozzle cap 84 is supported at the cap position U1. As shown in FIG. 8B, the slide cam 92 in this aspect is supported by the first groove 102 of the cam 90 at the highest position within the moving range, and the cap body 24 is also the second groove 104. Is supported at the highest position within the moving range.

  When shifting from the “print position” to the “cap position”, the platen 22 is moved from the nozzle facing position T1 toward the nozzle non-facing position T2, thereby bringing the nozzle cap 84 closer to the nozzle surface 46a. A “cap moving path (not shown)” for moving in the direction is opened, and then the nozzle cap 84 is moved to the cap position U1. In the present embodiment, since the platen 22 is driven by the slide cam 92 supported by the first groove 102 of the cam 90 and the cap body 24 is driven by the second groove 104 of the cam 90, the platen 22 and the cap body are driven. 24 is always integrated, and when the platen 22 is located at the nozzle facing position T1 (FIG. 7), the nozzle cap 84 is not considered to be moved to the cap position U1. Thus, it is possible to reliably prevent an accident that the motor 22 collides.

  By operating in this way, the nozzle cap 84 is brought into contact with the nozzle surface 46a, and a negative pressure is generated in the nozzle cap 84 by a suction device (not shown), thereby increasing the viscosity of the ink from within the nozzle 14. Etc. can be discharged. Further, the nozzle surface 46a can be capped until the next print instruction is received, and the state of the nozzles 14 can be maintained well.

<Wipe position>
When performing a wiping operation for wiping off ink adhering to the nozzle surface 46a when the printing operation is stopped, a part of the wiping mechanism (such as a wiper) needs to be disposed at a position facing the nozzle surface 46a. 22 and the nozzle cap 84 both get in the way. Therefore, when performing the wiping operation, the cam 90 is rotated counterclockwise β (FIG. 7B) from the “print position”, thereby selecting the “wipe position” shown in FIG. The “wipe position” is a mode in which the platen 22 is supported at the nozzle non-facing position T2 and the nozzle cap 84 is supported at the standby position U2. As shown in FIG. 9B, the slide cam 92 in this aspect is supported by the first groove 102 of the cam 90 at the highest position within the moving range, and the cap body 24 is supported by the second groove 104. Is supported at the lowest position within the moving range.

  The wiper has a blade having a length (that is, a length in the transport direction X) corresponding to the width of the nozzle surface 46a (that is, the length in the transport direction X). It is configured to slide in Y. The blade is disposed between the slide cam 92 and the ink discharge line head 16 at a position higher than the “sheet placement surface” of the platen 22, for example. When the wiping operation is performed, the platen 22 is supported at the nozzle non-facing position T2, and the blade is lowered to a position where it comes into contact with the nozzle surface 46a by an elevating device (not shown). The ink adhering to the nozzle surface 46a is removed.

[Modified example of liquid discharge line head]
According to the ink discharge line head 16 according to the above-described embodiment, the platen 22 is positioned at the nozzle facing position T <b> 1 (FIG. 4A) by the urging of the coil spring 52 even when the ink discharge device 10 is detached from the ink discharge device 10. Therefore, the nozzle surface 46 a can be protected by the platen 22. However, when the opening 68 (FIG. 3) is formed in the platen 22, foreign matter may enter from the opening 68. Therefore, in the liquid discharge line head 130 according to the modification shown in FIG. 10, the position of the positioning unit 50 is designed so that the platen 22 can be positioned at the nozzle protection position T3 (FIG. 10) different from the nozzle facing position T1. At the same time, a nozzle protection portion 132 that can cover the nozzle 14 at the nozzle protection position T3 is formed on the platen 22. In the case of this modification, positioning of the platen 22 with respect to the nozzle facing position T1 is performed by bringing the hypotenuse 110a of the slide cam 92 into contact with the action portion 72 of the platen 22.

  In the present embodiment, the platen 22 is configured to be rotationally driven about the rotation shaft 48. However, the drive mechanism of the platen 22 is not necessarily a “rotating mechanism”, and the platen 22 is transported. It may be a “slide mechanism” that is slid in the direction X or the line direction Y.

T1 ... Nozzle facing position T2 ... Nozzle non-facing position T3 ... Nozzle protection position U1 ... Cap position U2 ... Standby position Q ... Nozzle area P ... Print position R ... Transport path S ... Space W ... Center position X ... Transport direction Y ... Line Direction 10 ... Ink ejection device (liquid ejection device)
12 ... Paper 14 ... Nozzle 16 ... Liquid discharge line head 20 ... Cap device 22 ... Platen 24 ... Cap main body 26 ... Drive device 40 ... Line head main body 42 ... Mounting member 46 ... Nozzle plate 46a ... Nozzle surface 68 ... Opening 70 ... Guide surface 84 ... Nozzle cap 90 ... Cam 92 ... Slide cam 102 ... First groove 104 ... Second groove 130 ... Liquid discharge line head 132 ... Nozzle protector

Claims (10)

A plurality of nozzles that discharge liquid to the discharge target have a nozzle surface, and the plurality of nozzles are arranged so as to correspond from one end to the other end in the width direction of the discharge target. The line head body,
A platen disposed opposite to the nozzle surface and on which the discharge object is placed;
An attachment portion for attaching the platen to the line head body,
The platen includes a frame body including a pair of long side portions extending in a longitudinal direction of the line head main body and a pair of short side portions joined at both ends of the pair of long side portions;
A plurality of upstream placing pieces provided on one of the pair of long side portions, and a plurality of downstream placing pieces provided on the other of the pair of long side portions, wherein the plurality of upstream sides The mounting piece and the plurality of downstream mounting pieces are arranged in a straight line in a short direction perpendicular to the longitudinal direction of the line head body,
The platen is configured to be movable between a nozzle facing position facing the nozzle area where the plurality of nozzles are formed on the nozzle surface and a nozzle non-facing position not facing the nozzle area.
When the platen is located at the nozzle facing position, the discharge object is placed on the plurality of upstream placement pieces and the plurality of downstream placement pieces of the platen , and liquid is discharged from the nozzles. Discharged,
The platen is pivotally supported with respect to the line head main body via the mounting portion, and the mounting portion is rotatably supported on a side end surface of the line head main body in a direction in which the nozzle surface extends. ,
The rotation center of the mounting portion is located on the nozzle non-opposing position side with respect to the center position in the direction parallel to the nozzle surface on the side end surface,
The length of the mounting portion is set to such a length that the platen does not contact the corner of the head when the platen rotates from the nozzle facing position toward the non-facing position ,
The plurality of upstream mounting pieces are located at positions farther from the rotation center of the mounting portion than the plurality of downstream mounting pieces in a direction parallel to the nozzle surface, and The guide surface which inclines so that it may leave | separate from the said nozzle surface is formed in the edge part on the opposite side to the said several downstream mounting piece among the both ends of the upstream mounting piece of this. that is, the liquid discharge line head. The nozzle surface is formed to extend in the width direction of the discharge object,
The liquid discharge line head according to claim 1, wherein the platen is configured to be movable in a direction orthogonal to a direction in which the nozzle surface extends.   The liquid discharge line head according to claim 1, wherein the platen has an opening for allowing the liquid discharged from the nozzle to escape to the side opposite to the nozzle side.   The liquid discharge line head according to claim 3, wherein the platen includes a nozzle protection portion that covers the nozzle when the platen is located at a nozzle protection position different from the nozzle facing position. A liquid discharge line head for discharging liquid to a discharge target;
A transport device for transporting a discharge target to the liquid discharge line head;
The liquid discharge line head is
A line head main body having a nozzle surface in which a plurality of nozzles for discharging liquid are opened, and the plurality of nozzles are arranged so as to correspond from one end to the other end in the width direction of the discharge target;
A platen disposed opposite to the nozzle surface and on which a discharge object to be transported by the transport device is placed;
An attachment portion for attaching the platen to the line head main body;
The platen includes a frame body including a pair of long side portions extending in a longitudinal direction of the line head main body and a pair of short side portions joined at both ends of the pair of long side portions;
A plurality of upstream placing pieces provided on one of the pair of long side portions, and a plurality of downstream placing pieces provided on the other of the pair of long side portions, wherein the plurality of upstream sides The mounting piece and the plurality of downstream mounting pieces are arranged in a straight line in a short direction perpendicular to the longitudinal direction of the line head body,
The platen is configured to be movable between a nozzle facing position facing the nozzle area where the plurality of nozzles are formed on the nozzle surface and a nozzle non-facing position not facing the nozzle area.
When the platen is located at the nozzle facing position, the discharge object is placed on the plurality of upstream placement pieces and the plurality of downstream placement pieces of the platen , and liquid is discharged from the nozzles. Discharged,
The platen is pivotally supported with respect to the line head main body via the mounting portion, and the mounting portion is rotatably supported on a side end surface of the line head main body in a direction in which the nozzle surface extends. ,
The rotation center of the mounting portion is located on the nozzle non-opposing position side with respect to the center position in the direction parallel to the nozzle surface on the side end surface,
The length of the mounting portion is set to such a length that the platen does not contact the corner of the head when the platen rotates from the nozzle facing position toward the non-facing position ,
The plurality of upstream mounting pieces are located at positions farther from the rotation center of the mounting portion than the plurality of downstream mounting pieces in a direction parallel to the nozzle surface, and The guide surface which inclines so that it may leave | separate from the said nozzle surface is formed in the edge part on the opposite side to the said several downstream mounting piece among the both ends of the upstream mounting piece of this. that is, a liquid ejection apparatus. The platen is configured to be movable between a nozzle facing position facing the nozzle area where the plurality of nozzles are formed on the nozzle surface and a nozzle non-facing position not facing the nozzle area.
The liquid ejection apparatus according to claim 5, wherein a movement direction when the platen moves from the nozzle facing position to the nozzle non-facing position is substantially the same as a transport direction of the ejection target object. It is configured to be movable in the direction of approaching or separating from the nozzle surface, and includes a nozzle cap that covers the nozzle region when moved in the direction of proximity.
The cap moving path for moving the nozzle cap in a direction approaching the nozzle surface is opened by moving the platen from the nozzle facing position to the nozzle non-facing position. Liquid discharge device.   The guide surface which inclines so that it may move away from the said nozzle surface as it goes upstream is formed in the edge part located in the upstream of the conveyance direction of the discharge target object in the said platen. The liquid discharge apparatus according to 1. A cam mechanism for moving the platen between the nozzle facing position and the nozzle non-facing position;
The liquid ejecting apparatus according to claim 6 or 7, wherein the platen is supported by the cam mechanism at either the nozzle facing position or the nozzle non-facing position. The cam mechanism has a function of moving the nozzle cap between a cap position close to the nozzle surface and a standby position separated from the nozzle surface;
The cam mechanism supports the platen at the nozzle facing position and supports the nozzle cap at the standby position; and supports the platen at the nozzle non-facing position and supports the nozzle cap at the cap position. The liquid ejecting apparatus according to claim 9, wherein the second mode is switched between a second mode supported by the nozzle and a third mode of supporting the platen at the nozzle non-opposing position and supporting the nozzle cap at the standby position.

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