JP2008213351A - Droplet discharge apparatus and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a droplet discharge apparatus which prevents drying of a liquid inside nozzles arranged in nozzle faces of a plurality of head units arranged in a line, and also to provide an image forming apparatus with the droplet discharge apparatus. <P>SOLUTION: One film member 78 seals the nozzle faces 124 of head units 115 arranged in a line. Elastic protrusions 82 provided on the opposite faces to those where the film member 78 comes into contact with the nozzle faces 124, are deformed to press the film member 78 to the nozzle faces 124. Thus, the film member 78 is pressed by the elastic protrusions 82, and is closely attached to the respective nozzle faces 124 following them, so that drying of liquids inside the nozzles is prevented even if there exist steps among the nozzle faces 124. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a droplet discharge device that discharges droplets and an image forming apparatus including the droplet discharge device.

As a technique for preventing the liquid inside the nozzle provided on the nozzle surface from drying, a technique is disclosed in which a sheet-like porous member impregnated with a sealing liquid is brought into close contact with the nozzle surface at the end of the printing operation. (Patent Document 1)
JP 2001-253082 A

  On the other hand, in recent years, in order to support high-speed printing, a droplet discharge head in which a plurality of head units are arranged in the width direction of the recording medium may be used. Furthermore, in order to support full color, a plurality of droplet discharge heads may be arranged side by side in the recording medium conveyance direction.

  In the case of such a droplet discharge head, it is necessary to arrange adjacent head units close to each other in order to reduce the size.

  However, it is conceivable that the porous member of Patent Document 1 does not adhere to the nozzle surface by interfering with each other by bringing the head unit closer.

  As a countermeasure, it is conceivable that all the nozzle surfaces arranged in the droplet discharge head are brought into close contact with a large sheet-like porous member at a time, instead of bringing the porous member into close contact with each nozzle surface. However, there may be a step on the adjacent nozzle surface due to variations in the assembly of the head unit, etc., and this step prevents the porous member (hereinafter referred to as a sheet member) from coming into close contact with the nozzle surface, causing droplets in the nozzle to flow. It is possible to dry it.

  An object of the present invention is to prevent drying of the liquid inside the nozzles provided on the nozzle surfaces of a plurality of head units arranged in consideration of the above facts.

  According to a first aspect of the present invention, there is provided a droplet discharge device comprising: a droplet projecting head in which a plurality of head units that discharge droplets from nozzles formed on a nozzle surface are arranged; and a sheet member that seals the plurality of nozzle surfaces. And an elastic member that is provided on a side opposite to the surface that contacts the nozzle surface and that presses the sheet member against the nozzle surface.

  According to the above configuration, the sheet member seals the nozzle surface of the head unit. Further, the elastic member provided on the side opposite to the surface where the sheet member contacts the nozzle surface is deformed and presses the sheet member against the nozzle surface.

  Thus, since the sheet member is pressed by the elastic member and closely adheres to each nozzle surface following each nozzle surface, drying of the liquid inside the nozzle provided on the nozzle surface can be prevented.

  The droplet discharge device according to a second aspect of the present invention is characterized in that, in the first aspect, the surface of the elastic member that contacts the sheet member has an uneven shape.

  According to the above configuration, since the surface of the elastic member that contacts the sheet member has an uneven shape, even if a step is generated on the adjacent nozzle surface, the uneven portion is deformed in accordance with the step and the sheet member. Can be brought into close contact with each nozzle surface.

  According to a third aspect of the present invention, there is provided the liquid droplet ejection apparatus according to the second aspect, wherein the elastic member is in contact with the sheet member, and the elastic protrusion portion presses the sheet member with a plurality of protrusions on each nozzle surface. It is characterized by being.

  According to the above configuration, even if a step is generated between adjacent nozzle surfaces, the elastic protrusions, which are a plurality of protrusions, are deformed to absorb the step, and the sheet member can be brought into close contact with each nozzle surface.

  According to a fourth aspect of the present invention, there is provided the droplet discharge device according to the second aspect, wherein the elastic member is an elastic block portion that is in contact with the sheet member and divided into blocks for each nozzle surface. To do.

  According to the above configuration, even if there is a step in the adjacent nozzle surface, the elastic block portion divided into blocks for each nozzle surface is deformed to absorb the step, and the sheet member can be brought into close contact with each nozzle surface. .

  According to a fifth aspect of the present invention, there is provided a liquid droplet ejection apparatus according to any one of the first to fourth aspects, further comprising a liquid removing member that removes the liquid adhering to the sheet member.

  According to the above configuration, since the liquid removing member removes the droplets attached to the sheet member, when the sheet member is brought into close contact with the nozzle surface, the droplet attached to the sheet member adheres to the nozzle surface and drops on the nozzle. The discharge characteristics are not deteriorated.

  A droplet discharge device according to a sixth aspect of the present invention is the liquid droplet ejection device according to any one of the first to fifth aspects, further comprising a sealing liquid application member that applies a sealing liquid to the nozzle surface side of the sheet member. Features.

  According to the above configuration, since the sealing liquid application member applies the sealing liquid to the nozzle surface side of the sheet member, the adhesion between the nozzle surface and the sheet member can be improved.

  According to a seventh aspect of the present invention, there is provided an image forming apparatus comprising the liquid droplet ejection apparatus according to any one of the first to sixth aspects.

  According to the above configuration, since the image forming apparatus includes the droplet discharge device according to any one of claims 1 to 6, since the nozzle surface is prevented from being dried, the droplet can be stably maintained. (Ink) can be discharged onto the recording medium, and the image quality is stabilized.

  According to the present invention, it is possible to prevent the liquid inside the nozzles provided on the nozzle surfaces of the plurality of head units arranged side by side from being dried.

  An image forming apparatus 12 employing a droplet discharge device 48 according to a first embodiment of the present invention will be described with reference to FIGS.

  As shown in FIG. 12, a sheet feed tray 16 is provided in the lower part of the housing 14 of the image forming apparatus 12, and a sheet material P as a recording medium stacked in the sheet feed tray 16 is picked up by a pickup roll. 18 is taken out one by one.

  Further, the taken sheet material P is transported by a plurality of transport rollers 20 constituting a predetermined transport path 22. Hereinafter, the “transport direction” simply refers to the transport direction of the sheet material P, and “upstream” and “downstream” refer to upstream and downstream in the transport direction, respectively.

  In addition, an endless conveyance belt 28 that is stretched around a drive roll 24 and a driven roll 26 is disposed above the paper feed tray 16. Above the conveying belt 28, a droplet discharging device 48 including a droplet discharging unit 30 and a maintenance unit 34 is disposed, and the droplet discharging unit 30 faces the flat portion 28F of the conveying belt 28. Yes. This opposed region is a discharge region SE in which droplets are discharged from the droplet discharge unit 30.

  Further, the sheet material P transported to the transport path 22 is held by the transport belt 28 and reaches the discharge region SE, and in accordance with image information from the droplet discharge unit 30 in a state of facing the droplet discharge unit 30. A droplet is ejected.

  The droplet discharge unit 30 has an effective recording area that is longer than the width of the sheet material P (the length in the direction orthogonal to the conveying direction), and is yellow (Y), magenta (M), cyan (C ) And four droplet discharge heads 32 corresponding to the four colors of black (K) are arranged side by side in the transport direction, and correspond to a full-color image.

  Each droplet discharge head 32 is controlled by a recording head control unit (not shown). The recording head control unit determines, for example, the droplet discharge timing and the nozzle 112 (see FIG. 7) to be used according to image information. The drive signal is sent to the droplet discharge head 32.

  Further, an ink tank 54 that supplies ink (liquid) to each droplet discharge head 32 is provided in the upper portion of the housing 14 of the image forming apparatus 12.

  The droplet discharge unit 30 may be fixed in a direction orthogonal to the transport direction. However, if the droplet discharge unit 30 is configured to move as necessary, the resolution is higher in multipass image recording. Images can be recorded.

  Further, four maintenance units 34 corresponding to the respective droplet discharge heads 32 are arranged on both sides of the droplet discharge unit 30. When performing maintenance on the droplet discharge head 32, the droplet discharge unit 30 moves upward as shown in FIG. 11, and the maintenance unit 34 enters a gap provided between the conveyance belt 28 and the maintenance unit 34. It is like that. The nozzle surface 124 of the droplet discharge head 32 is sealed at a predetermined timing while facing the nozzle surface 124 (see FIG. 7) to prevent the ink inside the nozzle 112 from drying. Details of the maintenance unit 34 and the maintenance operation will be described later.

  As shown in FIG. 10, a charging roll 36 connected to a power source 38 is disposed on the upstream side of the droplet discharge head 32. The charging roll 36 is driven while sandwiching the conveyance belt 28 and the sheet material P with the driven roll 26, and is between a pressing position for pressing the sheet material P against the conveyance belt 28 and a separation position separated from the conveyance belt 28. Can be moved. At the pressing position, a predetermined potential difference is generated between the grounded driven roll 26 and the sheet material P can be electrostatically attracted to the conveying belt 28 by applying an electric charge to the sheet material P.

  Further, a peeling plate 40 is disposed on the downstream side of the droplet discharge head 32, and the sheet material P can be peeled from the transport belt 28. The peeled sheet material P is transported by a plurality of discharge rollers 42 constituting a discharge path 44 shown in FIG. 12 on the downstream side of the release plate 40 and discharged to a discharge tray 46 provided at the upper part of the housing 14. Is done.

  With the above configuration, in the image forming apparatus 12, the sheet material P accommodated in the paper feed tray 16 is picked up one by one by the pickup roll 18, and is conveyed by the plurality of conveyance rollers 20 configuring the predetermined conveyance path 22. It reaches the conveyor belt 28. Further, the sheet material P is pressed against the conveyance belt 28 by the charging roll 36 and is adsorbed (closely adhered) to the conveyance belt 28 by the voltage applied from the charging roll 36 and held. In this state, droplets are ejected from the nozzle 112 (see FIG. 7) provided in the droplet ejection head 32 of the droplet ejection unit 30 while the sheet material P passes through the ejection region SE by circulation of the transport belt 28. Thus, an image is recorded on the sheet material P. When recording an image in only one pass, the sheet material P is peeled from the transport belt 28 by the peeling plate 40 (see FIG. 10), transported by the discharge roller 42, and discharged to the paper discharge tray 46. On the other hand, when performing image recording by multi-pass, the sheet material P is circulated until it reaches the required number of times and passed through the discharge region SE, and then the sheet material P is peeled from the transport belt 28 by the peeling plate 40. Then, it is conveyed by the discharge roller 42 and discharged to the discharge tray 46.

  Next, the droplet discharge head 32 will be described.

  As shown in FIG. 9, the droplet discharge head 32 includes a head bar 110 set to a length corresponding to the maximum width of the sheet material P. The head bar 110 is supported by a support (not shown) at a position facing the conveyance path of the sheet material P in the image forming apparatus 12 (see FIG. 12). Furthermore, a plurality of head units 115 having a substantially parallelogram shape are arranged on the head bar 110. The individual head units 115 are fastened by fastening screws (not shown) to the head bar 110 and can be individually replaced.

  In addition, the sheet material P is conveyed in the direction of arrow A and printed by each head unit 115 disposed on the head bar 110. That is, when the sheet material P passes once below the head bar 110, it is possible to print on the entire width of the sheet material P without scanning the droplet discharge head 32. (One-pass printing corresponding to paper width, so-called Full Width Array (FWA)).

  Each head unit 115 includes a laminated flow path 114 in which a plurality of flow path plates are laminated, and a manifold 117 having an ink supply path for supplying ink to the laminated flow path 114. Two element substrates 116 and 118 are provided.

  Further, as shown in FIG. 8, a nozzle surface 124 in which nozzle regions 124 </ b> A and 124 </ b> B in which a plurality of nozzles 112 are disposed is provided on the opposite side of the laminated flow path 114 from the element substrates 116 and 118. ing. That is, the element substrates 116 and 118 are provided at positions corresponding to the two nozzle regions 124A and 124B, and droplets are ejected from the nozzles 112 into the substantially trapezoidal regions of the element substrates 116 and 118. A plurality of piezoelectric elements 186 (see FIG. 7) are provided.

  As shown in FIG. 7, the laminated flow path 114 includes a nozzle 112 that discharges droplets provided on the nozzle surface 124 and a pressure chamber 170, and the nozzle 112 and the pressure chamber 170 are communicated with each other through a nozzle communication path 158. ing. Further, a common ink channel 174 filled with ink introduced from an ink supply unit (not shown) is provided. The opening 180 of the common ink channel 174 and the pressure chamber 170 are communicated with each other through the ink supply channel 182.

  Further, the vibration plate 148 is bonded to the upper surface of the pressure chamber 170, the piezoelectric element 186 described above is bonded to the upper surface of the vibration plate 148, and the element substrate 116, via the ball solder 160, is bonded to the upper surface of the piezoelectric element 186. 118 is joined.

  Next, components of the laminated flow path 114 will be described.

  The laminated flow path 114 includes a nozzle plate 134 in which the nozzles 112 are formed, ink pool plates 136 and 138 in which holes are formed to serve as the nozzle communication path 158 and the common ink flow path 174, and the nozzle communication path 158 and the common ink flow. A through plate 140 in which a hole to be an opening 180 of the path 174 is formed, an ink supply path plate 142 in which a hole to be an ink supply path 182 is formed, and a pressure chamber plate 144 in which a hole to be a pressure chamber 170 is formed. And are laminated in order.

  With this configuration, when a driving voltage from the recording head control unit is applied to the piezoelectric element 186, the piezoelectric element 186 is deformed to pressurize the ink in the pressure chamber 170 and eject a droplet from the nozzle 112. It can be done.

  Next, the maintenance unit 34 that performs maintenance of the droplet discharge head 32 will be described.

  As shown in FIG. 3, when performing maintenance of the droplet discharge head 32, the droplet discharge unit 30 moves to the upper cap OFF position shown in FIG. 3A, and the transport belt 28 (see FIG. 11). ) And the droplet discharge unit 30 enters the maintenance unit 34. Then, with the maintenance unit 34 facing the nozzle surface 124, the nozzle surface 124 of the droplet discharge head 32 is sealed at a predetermined timing to prevent the ink inside the nozzle 112 from drying.

  The maintenance unit 34 is provided with a film member 78 as a sheet member for sealing the nozzle surface 124, and the film member 78 is elastically formed on the side opposite to the surface in contact with the nozzle surface 124. An elastic member 80 that is deformed and pressed against the nozzle surface 124 is provided. The film member 78 may be a plurality of film members instead of one sheet, but one film member 78 is simple and preferable.

  As shown in FIGS. 2A and 2B, the elastic member 80 provided on the rectangular base material 81 includes a plurality of columnar elastic protrusions whose tip portions contacting the film member 78 are formed in a spherical shape. Part 82.

  The material of the elastic protrusion 82 is preferably deformable by an external force and can be repeatedly used. Examples of the material include rubber, elastomer, polyethylene foam, and the like, and are selected in consideration of ink resistance and elasticity. The material of the elastic protrusion 82 of the first embodiment is polyurethane foam.

  The material of the film member 78 is preferably a member that is flexibly deformed in order to ensure followability to the nozzle surface 124 and sealing, and that has little gas permeation in order to prevent ink in the nozzle 112 from evaporating. For this reason, the sheet thickness is preferably a thin sheet of 1 mm or less. Furthermore, as a material, PET, polyethylene, polypropylene, polyimide, and the like can be considered, and are selected in consideration of ink resistance and elasticity. The material of the film member 78 of the first embodiment is polyimide and the plate thickness is 0.1 mm.

  Further, as shown in FIG. 3, the maintenance unit 34 is provided with a cylindrical guide rod 90 extending along the longitudinal direction of the droplet discharge head 32. The guide rod 90 includes a cap cleaning unit. 84 is movably attached along the guide rod 90.

  Further, the cap cleaning unit 84 is provided with an application roller 86 as a seal liquid application member for applying a seal liquid to the film member 78 and a cleaning roller 88 as a liquid removal member for removing ink adhering to the film member 78. It has been.

  Specifically, the cap cleaning unit 84 is provided with a motor 92, and the motor 92 rotates forward and backward in accordance with an instruction from the maintenance control unit 100, and the cap cleaning unit 84 moves along the guide rod 90 along the guide rod 90. It is possible to move from one end to the other end and from the other end to one end.

  Further, the cap cleaning unit 84 is provided with a shaft portion 94 having a sheet material conveying method as a rotation axis direction, and a central portion of a rectangular bracket 96 with rounded corners is rotated on the shaft portion 94. It is supported freely. An application roller 86 is rotatably supported at one end of the bracket 96 so that the sheet material conveying method is in the direction of the rotation axis. The application roller 86 is formed of an absorbing member that absorbs ink (for example, a non-woven fabric or a porous member). A predetermined amount of sealing liquid is supplied from a sealing liquid tank (not shown) by a pump, and the nozzle surface 124 of the film member 78. The sealing liquid is applied to the film member 78 by rolling the side.

  The seal liquid basically has the same physical properties as ink, but a solution containing no ink dye or pigment is used to prevent foreign matter from entering the nozzle 112.

  Further, a cleaning roller 88 is rotatably supported at the other end of the bracket 96 so that the sheet material conveying method is in the rotation axis direction. The cleaning roller 88 is formed of an absorbing member that absorbs ink, and rolls on the nozzle surface 124 side of the film member 78 to absorb and remove ink adhering to the film member 78.

  Here, an operation in which the maintenance control unit 100 controls the maintenance unit 34 and the like according to the flowchart shown in FIG. 5 to seal the nozzle surface 124 of the droplet discharge head 32 will be described.

  When printing is completed, the droplet discharge unit 30 moves to the upper cap OFF position shown in FIG. 3A, and the maintenance unit 34 enters below the droplet discharge head 32. In this state, the cap cleaning unit 84 is stopped at one end of the guide rod 90 and is disposed on the outer side in the direction perpendicular to the sheet material P conveyance with respect to the droplet discharge head 32.

  Next, in step 1000, the maintenance control unit 100 transmits a capping command. Upon receiving the capping command, the droplet discharge head 32 is lifted upward and moved to the retracted position shown in FIG. 3B where the cap cleaning unit 84 can move.

  Further, in step 2000, it is confirmed whether the droplet discharge head 32 has moved to the retracted position. If it has not moved to the retreat position, the process proceeds to step 3000 and a retreat command is transmitted to the droplet discharge head 32.

  When the droplet discharge head 32 moves to the retracted position, the process proceeds to step 4000. In step 4000, the maintenance control unit 100 transmits a seal liquid application command to the maintenance unit 34, and the process proceeds to step 5000.

  In step 5000, the sealing liquid is applied to the film member 78 by the application roller 86.

  Specifically, as shown in FIG. 3B, the guide roller 86 is disposed below the cleaning roller 88 and is disposed at an application position where the seal liquid can be applied to the film member 78. The cap cleaning unit 84 stopped at one end of 90 is moved toward the other end of the guide rod 90. As a result, the application roller 86 rolls on the nozzle surface 124 side of the film member 78 and applies the sealing liquid to the film member 78.

  When the sealing liquid is applied to the film member 78, the process proceeds to step 6000, where the cap cleaning unit 84 is stopped at the other end of the guide rod 90 as illustrated in FIG. 3C, and the process proceeds to step 7000.

  In step 7000, the droplet discharge head 32 is moved downward to move to the cap position shown in FIG. 4A where the nozzle surface 124 is in close contact with the film member 78.

  Here, as shown in FIG. 1A, a step (for example, a step of several to several tens of microns) may occur on the adjacent nozzle surfaces 124 due to the assembly variation of the head unit 115 or the like. . However, as shown in FIG. 1B, when the droplet discharge head 32 moves to the cap position and the nozzle surface 124 is pressed against the film member 78, the cylindrical protrusion 82 bends according to the level difference. Thus, the film member 78 can be brought into close contact with the nozzle surface 124.

  Next, an operation in which the maintenance control unit 100 controls the maintenance unit 34 and the like according to the flowchart shown in FIG. 6 to separate the nozzle surface 124 of the droplet discharge head 32 from the film member 78 will be described.

  When printing is started in a state where the droplet discharge head 32 is disposed at the cap position shown in FIG. 4A, the maintenance control unit 100 transmits a cap OFF command in Step 1500 and the process proceeds to Step 2500. .

  In Step 2500, the droplet discharge head 32 that has received the cap OFF command is lifted upward and moved to the retracted position shown in FIG. 4B where the cap cleaning unit 84 can move.

  Further, in step 3500, the bracket 96 is rotated counterclockwise (in the direction of arrow D shown in FIG. 4A) about the shaft portion 94, and the cleaning roller 88 absorbs and removes ink adhering to the film member 78. It can be moved to the cleaning position shown in FIG.

  Next, in step 4500, as shown in FIG. 4C, the cap cleaning unit 84 stopped at the other end of the guide rod 90 is moved toward one end of the guide rod 90. As a result, the cleaning roller 88 rolls on the nozzle surface 124 side of the film member 78, absorbs and removes ink adhering to the film member 78, and proceeds to step 5500.

  In step 5500, the cap cleaning unit 84 stops at one end of the guide rod 90, and the droplet discharge head 32 prepares for the printing operation.

  As described above, when sealing the nozzle surface 124, the film member 78 can be brought into close contact with each nozzle surface 124 by pressing the film member 78 with the cylindrical protrusion 82. Further, the ink inside the nozzle 112 can be prevented from drying.

  In addition, the adhesiveness between the nozzle surface 124 and the film member 78 can be improved by applying the sealing liquid to the film member 78 before the film member 78 is adhered to the nozzle surface 124.

  Further, after the nozzle surface 124 is separated from the film member 78, the cleaning roller 88 absorbs and removes the ink attached to the film member 78. In this way, by removing the ink from the film member 78 before the ink is dried, the ink can be reliably removed from the film member 78 without any remaining ink wiping. As a result, the ink adhering to the film member 78 does not reattach to the nozzle surface 124 and the ink ejection characteristics of the nozzle are not deteriorated.

  Although the present invention has been described in detail with respect to specific embodiments, the present invention is not limited to such embodiments, and various other embodiments are possible within the scope of the present invention. It is clear to the contractor. For example, in the above-described embodiment, the image forming apparatus 12 including the droplet discharge head 32 that is longer than the width of the sheet material P has been described as an example. it can.

  Moreover, in the said embodiment, although the adhesiveness of the film member 78 and the nozzle surface 124 was improved using the sealing liquid, especially when not closely using a sealing liquid, even if it does not use a sealing liquid. Good.

  Moreover, in the said embodiment, although the elastic member 80 was made into the column-shaped elastic projection part 82, it may replace with this and other protrusion shapes, such as a trapezoid cone shape or a square pyramid shape, may be sufficient.

  Further, in the above embodiment, only the cylindrical elastic protrusion 82 is the elastic member 80, but instead, the elastic member 80 is integrally formed with the base member 81 of the elastic protrusion 82 as the elastic member 80. May be.

  Moreover, in the said embodiment, although the cleaning roller 88 was used as a cleaning member which wipes off the ink adhering to the film member 78, it may replace with this and the ink adhering to the film member 78 may be wiped off with a rubber blade.

  Next, an image forming apparatus 12 employing a droplet discharge device 110 according to a second embodiment of the present invention will be described with reference to FIGS.

  In addition, about the same member as 1st Embodiment, the same code | symbol is attached | subjected and the description is abbreviate | omitted.

  As shown in FIG. 14, in this embodiment, as in the first embodiment, the elastic member 80 is not a cylindrical elastic protrusion, but instead, the elastic member 80 is formed by the nozzle surface 124 (see FIG. 13). ) Are formed into a rectangular elastic block portion 108 divided into blocks.

  With this configuration, as shown in FIGS. 13A and 13B, even when there is a step between adjacent nozzle surfaces 124, the nozzle surface 124 at the capping position is divided into blocks for each nozzle surface 124. Each nozzle surface 124 can be sealed by the block portion 108 being pressed through the film member 78.

  Although the present invention has been described in detail with respect to specific embodiments, the present invention is not limited to such embodiments, and various other embodiments are possible within the scope of the present invention. It is clear to the contractor. For example, in the above embodiment, the block portion 108 has a quadrangular shape based on the shape of the nozzle surface 124. However, the block portion 108 is not particularly limited to a quadrangular shape, and may be other shapes as long as it is determined based on the shape of the nozzle surface 124. There may be.

  Next, an image forming apparatus 12 employing a droplet discharge device 120 according to a third embodiment of the present invention will be described with reference to FIGS.

  In addition, about the same member as 1st Embodiment, the same code | symbol is attached | subjected and the description is abbreviate | omitted.

  As shown in FIGS. 15A and 15B, in this embodiment, unlike the first embodiment, a film member is not used as a sheet member to be brought into close contact with the nozzle surface 124. Instead, a sheet is used. A porous member 122 that can be impregnated with a sealing liquid is used as the member.

  The nozzle surface 124 at the capping position shown in FIG. 15B and the porous member 122 are in close contact with each other, and the material of the porous member 122 is the hole diameter for impregnating and holding the sealing liquid and the sealing liquid. A member that has hydrophilicity and liquid repellency with respect to ink and that can be flexibly deformed to ensure followability to the nozzle surface 124 and sealability is desirable, and a plate thickness of 1 mm or less is preferable.

  The material of the porous member 122 of the third embodiment uses PTFE and a plate thickness of 0.1 mm. In addition to PTFE, PFE, PVDF, etc. can be used.

  Further, the cap cleaning unit 84 is not provided with an application roller 86 (see FIG. 3) for applying the sealing liquid to the film member 78 (see FIG. 3), and replenishing the porous member 122 with the sealing liquid. A roller (not shown) is provided.

  Further, the cap cleaning unit 84 is not provided with a cleaning roller 88 that removes ink attached to the film member 78, and a porous member cleaning roller as a cleaning member that cleans ink attached to the porous member 122. (Not shown) is provided.

  Further, as the sealing liquid to be replenished to the porous member 122, oils are preferable, and silicon oil is used in this embodiment.

  Next, an image forming apparatus 12 employing a droplet discharge device 130 according to a fourth embodiment of the present invention will be described with reference to FIGS.

  In addition, about the same member as 2nd Embodiment, the same code | symbol is attached | subjected and the description is abbreviate | omitted.

  As shown in FIGS. 16A and 16B, in this embodiment, unlike the second embodiment, a film member is not used as a sheet member to be brought into close contact with the nozzle surface 124. Instead, a sheet is used. A porous member 132 that can be impregnated with a sealing liquid is used as the member.

  Specifically, the nozzle surface 124 and the porous member 132 at the capping position shown in FIG. 16B are in close contact with each other. The material of the porous member 132 includes a hole diameter for impregnating and holding the sealing liquid, a seal It is desirable to use a member that is hydrophilic with respect to the liquid and has liquid repellency with respect to the ink and that can be flexibly deformed to ensure followability to the nozzle surface 124 and sealability. good.

  The material of the porous member 132 of the fourth embodiment uses PTFE and a plate thickness of 0.1 mm. In addition to PTFE, PFE, PVDF, etc. can be used.

  Further, the cap cleaning unit 84 is not provided with an application roller 86 (see FIG. 3) for applying the sealing liquid to the film member 78 (see FIG. 3), and replenishing the porous member 132 with the sealing liquid. A roller (not shown) is provided.

  Further, the cap cleaning unit 84 is not provided with the cleaning roller 88 for removing the ink attached to the film member 78, and the porous member cleaning roller as a cleaning member for cleaning the ink attached to the porous member 132. (Not shown) is provided.

  In addition, oils are preferable for the sealing liquid applied to the porous member 132, and silicon oil is used in this embodiment.

(A) It is the front view which showed the droplet discharge head and the maintenance unit which comprise the droplet discharge apparatus which concerns on 1st Embodiment of this invention, and the droplet discharge head showed the state of the retracted position. (B) It is the front view which showed the droplet discharge head and the maintenance unit which comprise the droplet discharge apparatus which concerns on 1st Embodiment of this invention, and the droplet discharge head showed the state of the cap position. (A) It is the perspective view which showed the elastic member which comprises the droplet discharge apparatus which concerns on 1st Embodiment of this invention. (B) It is the front view which showed the elastic member which comprises the droplet discharge apparatus which concerns on 1st Embodiment of this invention. (A) It is the front view which showed the droplet discharge head and the maintenance unit which comprise the droplet discharge apparatus which concerns on 1st Embodiment of this invention, and the droplet discharge head showed the state of the cap OFF position. (B) It is the front view which showed the droplet discharge head and maintenance unit which comprise the droplet discharge apparatus which concerns on 1st Embodiment of this invention, and the droplet discharge head showed the state of the retracted position. (C) It is the front view which showed the droplet discharge head and the maintenance unit which comprise the droplet discharge apparatus which concerns on 1st Embodiment of this invention, and the droplet discharge head showed the state of the cap position. (A) It is the front view which showed the droplet discharge head and the maintenance unit which comprise the droplet discharge apparatus which concerns on 1st Embodiment of this invention, and the droplet discharge head showed the state of the cap position. (B) It is the front view which showed the droplet discharge head and maintenance unit which comprise the droplet discharge apparatus which concerns on 1st Embodiment of this invention, and the droplet discharge head showed the state of the retracted position. FIG. 3C is a front view showing the droplet discharge head and the maintenance unit that constitute the droplet discharge apparatus according to the first embodiment of the present invention, and showing the droplet discharge head in a cap OFF position. It is the flowchart which showed operation | movement of the maintenance unit which comprises the droplet discharge apparatus which concerns on 1st Embodiment of this invention. It is the flowchart which showed operation | movement of the maintenance unit which comprises the droplet discharge apparatus which concerns on 1st Embodiment of this invention. It is sectional drawing of the lamination | stacking flow path which concerns on 1st Embodiment of this invention. It is the bottom view which showed the nozzle surface which concerns on 1st Embodiment of this invention. 1 is a perspective view showing a droplet discharge head according to a first embodiment of the present invention. 1 is a schematic configuration diagram illustrating an image forming unit of an image forming apparatus according to a first embodiment of the present invention. 1 is a schematic configuration diagram illustrating an image forming apparatus according to an embodiment of the present invention and a state when a maintenance unit is operated. 1 is a schematic configuration diagram illustrating an image forming apparatus according to an embodiment of the present invention. (A) It is the front view which showed the droplet discharge head and the maintenance unit which comprise the droplet discharge apparatus which concerns on 2nd Embodiment of this invention, and the droplet discharge head showed the state of the retracted position. (B) It is the front view which showed the droplet discharge head and the maintenance unit which comprise the droplet discharge apparatus which concerns on 2nd Embodiment of this invention, and the droplet discharge head showed the state of the cap position. (A) It is the perspective view which showed the elastic member which comprises the droplet discharge apparatus which concerns on 2nd Embodiment of this invention. (B) It is the front view which showed the elastic member which comprises the droplet discharge apparatus which concerns on 2nd Embodiment of this invention. (A) It is the front view which showed the droplet discharge head and the maintenance unit which comprise the droplet discharge apparatus which concerns on 3rd Embodiment of this invention, and the droplet discharge head showed the state of the retracted position. (B) It is the front view which showed the droplet discharge head and maintenance unit which comprise the droplet discharge apparatus which concerns on 3rd Embodiment of this invention, and the droplet discharge head showed the state of the cap position. (A) It is the front view which showed the droplet discharge head and maintenance unit which comprise the droplet discharge apparatus which concerns on 4th Embodiment of this invention, and the droplet discharge head showed the state of the retracted position. (B) It is the front view which showed the droplet discharge head and the maintenance unit which comprise the droplet discharge apparatus which concerns on 4th Embodiment of this invention, and the droplet discharge head showed the state of the cap position.

Explanation of symbols

12 Image forming apparatus 32 Droplet discharge head 34 Maintenance unit 48 Droplet discharge apparatus 78 Film member (sheet member)
80 Elastic member 82 Elastic protrusion 86 Application roller (sealing liquid application member)
88 Cleaning roller (liquid removing member)
108 Elastic block portion 110 Droplet discharge device 112 Nozzle 115 Head unit 120 Droplet discharge device 122 Porous member (sheet member)
124 Nozzle surface 130 Droplet discharge device 132 Porous member (sheet member)

Claims (7)

A droplet projecting head in which a plurality of head units that eject droplets from nozzles formed on the nozzle surface are arranged;
A sheet member that seals the plurality of nozzle surfaces;
An elastic member that is provided on a side opposite to a surface that contacts the nozzle surface, and that presses the sheet member against the nozzle surface;
A droplet discharge apparatus comprising:   The droplet discharge device according to claim 1, wherein a surface of the elastic member that contacts the sheet member has an uneven shape.   3. The droplet discharge device according to claim 2, wherein the elastic member is an elastic protrusion that contacts the sheet member and presses the sheet member with a plurality of protrusions on each of the nozzle surfaces.   The droplet discharge device according to claim 2, wherein the elastic member is an elastic block portion that is in contact with the sheet member and divided into blocks for each nozzle surface.   5. The liquid droplet ejection apparatus according to claim 1, further comprising a liquid removing member that removes the liquid attached to the sheet member.   6. The droplet discharge device according to claim 1, further comprising a sealing liquid application member that applies a sealing liquid to the nozzle surface side of the sheet member.   An image forming apparatus comprising the droplet discharge device according to claim 1.

Images