JP2007152940A - Ink-jet recording apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ink-jet recording apparatus that can relieve a problem that inside of an apparatus is polluted with ink as a result of a wiping operation. <P>SOLUTION: The wiping operation is performed by moving a wiper 30 from one longitudinal end to the other longitudinal end of an ink ejection face 2b of an ink-jet head. When the wiper 30 reaches a position between the other longitudinal end of the ink ejection face 2b and a nozzle opening nearest to the other longitudinal end, the wiper 30 is stopped for a time and then spaced apart from the ink ejection face 2b. Most of ink which has been gathered in the wiping operation is kept on the wiper 30 and moved away from the ink ejection face 2b. After the ink adhering to the rear face of the wiper 30 is removed by an ink absorber 16 which is held on the L-shaped supporter 15a of a holder, a rewiping is performed from a vicinity of the point at which the wiper has been spaced apart. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an ink jet recording apparatus that ejects ink onto a recording medium.

  2. Description of the Related Art An ink jet recording apparatus having a head in which a large number of nozzles for ejecting ink are formed and a wiper for wiping off ink adhering to an ink ejection surface of the head, that is, a surface in which nozzle openings are formed is known (patent) Reference 1). By moving the wiper made of an elastic material relative to the head while making contact with the ink ejection surface of the head, that is, by wiping, the nozzle opening and excess ink adhering to the periphery thereof are removed, and the vicinity of the nozzle opening The ink meniscus formed in the above is adjusted to a suitable state.

According to the apparatus of Patent Document 1, the inclined plate is provided on the carriage that holds the head, and the wiper is temporarily stopped in a state where the tip of the wiper is in pressure contact with the inclined plate after the end of the wiper exceeds the ink ejection surface of the head. Thereafter, the wiper is slightly moved in a direction perpendicular to the moving direction at the time of wiping, and wiping is started again. When the inclined plate is not provided, when the tip of the wiper that is bent at the time of wiping exceeds the end of the ink ejection surface of the head, the ink is scattered around as it returns to its original state due to its restoring force. However, the apparatus of Patent Document 1 can prevent such a situation by providing an inclined plate.
FIG. 10 of Japanese Patent Application Laid-Open No. 2004-74774

  However, in the apparatus of the above-mentioned document 1, ink easily enters the gap between the inclined plate and the head. The ink that has entered the gap falls naturally due to the action of gravity, or is scattered when the user removes the head from the carriage in order to jam the recording medium. As a result, the inside of the apparatus is contaminated with ink.

  A possible solution is to fill the gap with a sealing material. However, if the sealing material is filled, it is difficult to replace the head, and it is necessary to select a sealing material that has ink resistance. It also causes an increase in cost.

  The ink ejection surface of the head is usually water-repellent, but if the water-repellent finish is not applied near the end of the head, for example due to cost problems, the water-repellent finish is not applied. When the wiper is separated from the ink discharge surface in the processing area, the ink remains on the ink discharge surface without being held by the wiper, and then drops naturally due to the action of gravity, and the inside of the apparatus is contaminated with ink as described above. The problem of being done arises.

  An object of the present invention is to provide an ink jet recording apparatus capable of reducing the problem that the inside of the apparatus is contaminated with ink by performing wiping.

  In order to achieve the above object, an ink jet recording apparatus according to the present invention includes an ink jet head having an ink discharge surface in which openings of a plurality of nozzles for discharging ink are formed, and a wiper for wiping off ink adhering to the ink discharge surface. A drive mechanism that drives at least one of the inkjet head and the wiper, and a wiper direction from one end of the ink ejection surface toward the other end while the wiper is in contact with the ink ejection surface with respect to the inkjet head Between the opening of the nozzle closest to the other end and a change position between the opening and the other end and changing so that the ink adhesion performance increases in the wiping direction. A wipe that controls the drive mechanism to separate the wiper from the ink ejection surface. It includes a ring control means.

  In the above configuration, the wiper wipes all of the nozzle openings formed on the ink discharge surface, and is separated from the ink discharge surface before reaching the change position where the ink adhesion performance changes so that the ink is changed to the change position. It is possible to avoid the problem of reaching the head and remaining in the head. Therefore, the problem that the inside of the apparatus is contaminated with ink by performing wiping can be reduced.

  In the ink jet recording apparatus according to the present invention, the ink discharge surface is subjected to water repellency, and the wiping control unit separates the wiper from the ink discharge surface in the region where the water repellency is applied. Is preferred. When the wiper is separated from the ink ejection surface in the water-repellent area in this way, the ink scraped by the wiping moves smoothly to the wiper, and almost no ink remains on the ink ejection surface. Thereby, the problem that the inside of the apparatus is contaminated with ink can be more reliably reduced.

  It is preferable that the inkjet head has a length equal to or greater than the width of the recording medium, and the wiping control unit controls the drive mechanism so as to relatively move the wiper along the longitudinal direction of the inkjet head. A line-type head having a length equal to or larger than the width of the recording medium is relatively long. When the wiper is relatively moved along the longitudinal direction of the head in wiping, a large amount of ink is scraped by the wiper. Even in this case, the problem that the inside of the apparatus is contaminated with ink can be reduced.

  A holder for holding the inkjet head by supporting the one end and the other end of the ink ejection surface in the inkjet head is further provided, and the change position is the other end of the ink ejection surface. preferable. In this case, it is possible to prevent ink from entering the gap between the head and the holder.

  The holder includes a first end support portion that supports the one end of the ink discharge surface of the inkjet head and a second end support portion that supports the other end, and the other end of the ink discharge surface in the other end support portion. It is preferable that the part which adjoins becomes a round shape. By forming a radius in the holder in this way, it is possible to effectively prevent ink from entering the gap between the head and the holder.

  It is preferable that the wiping control means controls the drive mechanism so that the wiper stops for a predetermined time while being in contact with the ink discharge surface immediately before the wiper is separated from the ink discharge surface. By stopping the wiper for a predetermined time, most of the ink scraped by wiping moves from the ink ejection surface to the wiper, and almost no ink remains on the ink ejection surface. Therefore, it is possible to more effectively prevent the inside of the apparatus from being contaminated with ink.

  A first driving source that applies a driving force to the driving mechanism so that the wiper moves relative to the inkjet head along the wiping direction; and the wiper moves in a direction intersecting the ink ejection surface. Thus, a second drive mechanism that applies a drive force to the drive mechanism may be provided separately.

  The drive mechanism includes a slide mechanism that moves the wiper along the wipe direction, and a gear mechanism that moves the wiper in a direction intersecting the ink discharge surface, and the slide mechanism supports the wiper. A wiper holder, a guide for slidably supporting the wiper holder along the wipe direction, first and second shafts spaced apart with respect to the wipe direction so as to sandwich the inkjet head, and the first and first shafts A pulley fixed to each of the two shafts, and an endless belt that is wound around the pulley and is stretched between the pulleys and to which the wiper holder is fixed, wherein the first shaft is the first shaft. When rotated by the driving force of the driving source, one of the pulleys and a pulley fixed to the first shaft When the belt runs, the wiper holder slides in the wiping direction while being supported by the guide, and the gear mechanism is rotatably attached to the second shaft and the guide is fixed. A first gear and a second gear, wherein the first gear has an arc-shaped end surface centered on the first shaft, and the second gear is on the one end surface. When the second gear rotates with the driving force of the second drive source, the second shaft and the first gear follow an arc shape centered on the first shaft. The wiper holder supported by the guide may move in a direction intersecting the ink ejection surface.

  The ink jet recording apparatus according to the present invention further comprises an ink absorber, and the wiping control means drives the drive so that the ink adhering to the wiper separated from the ink ejection surface is absorbed by the ink absorber. It is preferable to control the mechanism. In this case, the ink attached to the wiper can be removed.

  The wiping control means moves the wiper in the wiping direction while contacting the ink discharge surface from the vicinity of the separation position from the ink discharge surface after the ink absorber absorbs ink adhering to the wiper. It is preferable to control the drive mechanism so as to move relative to each other. By wiping the ink ejection surface again in this way, it is possible to remove ink that remains slightly on the ink ejection surface after the initial wiping.

  The wiping control means is configured so that the ink adhering to the back surface in the wipe direction in the wiper after the wiper is separated from the ink discharge surface and before coming into contact with the ink discharge surface again. It is preferable to control the drive mechanism so as to be absorbed by the above. When the wiper is separated from the ink discharge surface, the ink tends to adhere to the back surface of the wiper in the wipe direction. If the wiper is brought into contact with the ink ejection surface again in such a state, the ink attached to the back surface of the wiper tends to adhere to the ink ejection surface. Therefore, by removing the ink adhering to the back surface of the wiper before rewiping, such a problem can be suppressed.

  The wiping control means is configured such that the wiper moving speed in the wiping direction after contacting the ink ejection surface again after being separated from the ink ejection surface is the wiper in the wiping direction before being separated from the ink ejection surface. It is preferable to control the drive mechanism so as to be smaller than the moving speed of the first drive mechanism. In this way, by reducing the wiper moving speed at the time of rewiping than before the separation from the ink ejection surface, even if the wiper reaches the other end of the ink ejection surface at the time of rewiping, the ink collected by the wiper is collected. It becomes difficult to get into the gap between the head and the holder or to scatter.

  The wiping control means is configured such that after the wiper is separated from the ink ejection surface and again comes into contact with the ink ejection surface and further moves relative to the wipe direction, the ink adhering to the wiper is absorbed by the ink absorber. Thus, it is preferable to control the drive mechanism. In this case, the next wiping can be performed with almost no ink adhering to the wiper.

  It is preferable that the ink absorber is held by the other end support portion that supports the other end of the ink discharge surface of the holder that holds the inkjet head. Thereby, the movement of the wiper or the head accompanying the ink removal from the wiper using the ink absorber can be efficiently performed in a short time.

  Preferably, the wiper has flexibility, and the wiping control means controls the drive mechanism so that the amount of deflection of the wiper changes. In this case, by making the amount of flexure of the wiper suitable for the purpose, each operation such as wiping, re-wiping, and ink removal from the wiper by the ink absorber can be performed efficiently.

  Specifically, the wiping control means has a driving mechanism that reduces the amount of flexure of the wiper after contacting the ink ejection surface again after separation from the ink ejection surface than before separation from the ink ejection surface. Is preferably controlled. In this way, by making the wiper flexure at the time of rewiping relatively small, it is possible to effectively suppress ink scattering due to elastic recovery of the wiper at the end of rewiping.

  Further, the wiping control means may cause the amount of flexure of the wiper to be larger when the ink adhering to the wiper separated from the ink ejection surface is absorbed by the ink absorber than before the separation from the ink ejection surface. In addition, it is preferable to control the drive mechanism. As described above, when the ink is removed from the wiper using the ink absorber, the ink can be efficiently removed from the wiper by bending the wiper relatively large. In the subsequent wiping, the ink remaining on the ink ejection surface can be more reliably removed.

  The ink absorber has a cylindrical shape, a rotational drive mechanism that rotates the ink absorber around a central axis, a scraper having a tip that contacts the peripheral surface of the ink absorber, and the ink absorption Absorber rotation control means for controlling the rotation drive mechanism so that the body rotates may further be provided. In this case, by rotating the ink absorber, the ink existing in the ink absorber can be removed by the scraper, and the ink absorbing power of the ink absorber can be maintained in a good state.

  The ink jet recording apparatus according to the present invention further includes a scraper for holding the ink absorber, the tip of the scraper is exposed, and the wiping control means is configured to cause the wiper to be in contact with the tip of the scraper. The drive mechanism may be controlled so that the ink adhering to the ink is absorbed by the ink absorber through the scraper. In this case, it is possible to prevent deterioration of the ink absorber due to friction or the like, and it is possible to avoid a situation in which ink or foreign matter attached to the ink absorber adheres to the wiper.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

  First, an overall configuration of an ink jet printer according to an embodiment of the present invention will be described with reference to FIGS. 1, 2, 3, and 4. The ink jet printer 1 of this embodiment is a line type color ink jet printer having four ink jet heads 2.

  A head main body 2a, which will be described in detail later, is provided at the lower end of each head 2, and the four heads 2 are arranged in parallel along the paper transport direction while bringing the head main bodies 2a close to each other. The head main body 2a has an elongated rectangular plane (see FIG. 2) along a direction perpendicular to the paper surface of FIG. 1, that is, a direction orthogonal to the paper transport direction, and the length is larger than the width of the paper as a recording medium. long. The lower surface of the head main body 2a is an ink discharge surface 2b on which a large number of nozzle openings 28 (see FIG. 3) for discharging ink are formed. The ink discharge surfaces 2b of the four head main bodies 2a are respectively magenta, yellow, Cyan and black ink are ejected. The entire surface of the ink discharge surface 2b is water repellent.

  As shown in FIGS. 2 and 3, the head main body 2 a includes a channel unit 22 having a rectangular shape in plan view formed by laminating a total of nine plates, and a staggered shape on the upper surface of the channel unit 22. 4 actuator units 21 arranged in a shape. On the lower surface of the flow path unit 22, a large number of nozzle openings 28 are formed in a portion corresponding to the actuator unit 21 to form an ink discharge surface 2 b (see FIG. 1). A large number of pressure chambers 23 communicating with the nozzles are formed on the upper surface of the flow path unit 22, and the actuator unit 21 is disposed so as to cover the pressure chambers 23. Inside the flow path unit 22, there are a manifold flow path 25 for storing ink supplied to the pressure chamber 23, a sub manifold flow path 25a branched from the manifold flow path 25, and a sub manifold flow path as shown in FIG. An individual ink flow path 32 is formed for each nozzle from 25 a through the pressure chamber 23 to the nozzle opening 28. Ink in an ink tank (not shown) is supplied to the manifold channel 25 through an opening 25b formed on the upper surface of the channel unit 22, and further distributed to each pressure chamber 23 through the sub-manifold channel 25a. . When the pressure is selectively applied to the pressure chamber 23 by the actuator unit 21, the pressure of the ink in the pressure chamber 23 rises, and the ink is ejected from the nozzle opening 28 communicating with the pressure chamber 23. It has become.

  As shown in FIG. 1, the ink discharge surfaces 2b of the four heads 2 are arranged in the horizontal direction, and the ink discharge surfaces 2b and the upper loop surface of the transport belt 8 are opposed to each other with a small amount of gap. A belt conveyance mechanism 13 is disposed. The belt conveyance mechanism 13 includes two rollers 6 and 7 and a loop-shaped conveyance belt 8 wound so as to be bridged between the two rollers 6 and 7, and one roller 6 is indicated by an arrow X in FIG. By rotating in the clockwise direction, the conveyor belt 8 travels, and the other roller 7 is also rotated accordingly. The belt conveyance mechanism 13 also has a belt guide 51 disposed in a region surrounded by the conveyance belt 8. The belt guide 51 has a substantially rectangular parallelepiped shape having the same width as that of the conveyor belt 8, and supports the conveyor belt 8 with its upper surface contacting the back surface of the upper loop of the conveyor belt 8.

  Sheets as recording media are stacked and accommodated in the sheet feeding unit 11 (left side in FIG. 1), and are sequentially sandwiched between a pair of sheet feeding rollers 5a and 5b from the top one on the conveying belt 8 of the belt conveying mechanism 13. Sent to. The sheet is held on the upper loop surface of the conveyor belt 8 and moves below the ink ejection surface 2b of the head 2 as the conveyor belt 8 travels. At this time, ink of each color is ejected from the ink ejection surface 2b. As a result, a desired color image is formed on the paper. The paper on which the image is formed in this manner is peeled off from the surface of the conveyor belt 8 by the peeling plate 10 and sent to the paper discharge unit 12 on the right side of FIG.

  The conveyor belt 8 has a two-layer structure of a polyester base material impregnated with urethane and silicon rubber, and the surface is made of silicon rubber. The paper transported by the paper feed rollers 5a and 5b is pressed onto the surface of the transport belt 8 by the pressing member 9a, and is transported as the transport belt 8 travels while being held on the surface by adhesion. A pressing member 9 b is also provided on the opposite side of the pressing member 9 a across the four heads 2, that is, on the downstream side in the paper transport direction.

  The four heads 2 are all supported by a holder 15 so that their positions are fixed. As shown in FIG. 4, both ends of each head 2 in the head body 2a in the longitudinal direction, that is, the direction perpendicular to the paper surface of FIG. 1, are cut out, and the L-shaped holder 15 is formed in each cut-out portion. The support portion 15a is engaged. That is, the holder 15 supports one end and the other end of the ink discharge surface 2b in the head main body 2a of each head 2 via the pair of L-shaped support portions 15a. The portions of the L-shaped support portion 15a adjacent to the one end in the longitudinal direction and the other end in the longitudinal direction of the ink ejection surface 2b are rounded.

  An ink absorber 16 capable of absorbing ink is attached to a side surface of the pair of L-shaped support portions 15a of the holder 15 that is further away from a standby position of a wiper 30 described later. The ink absorber 16 may be made of a porous material such as urethane.

  As shown in FIG. 1, the belt conveyance mechanism 13 is supported by an elevating mechanism including a chassis 52 and a cylindrical member 53 that can rotate about an eccentric shaft 54 so as to be movable up and down. The chassis 52 is supported on the peripheral surface of a cylindrical member 53 disposed below, while rotatably supporting the rollers 6 and 7 of the belt conveyance mechanism 13. When the cylindrical member 53 is rotated about the eccentric shaft 54, the upper end height of the cylindrical member 53 changes, and the chassis 52 moves up and down together with the belt conveying mechanism 13.

  As shown in FIG. 4, the ink jet printer 1 further includes a wiper 30 for wiping off ink adhering to the ink ejection surface 2b. Although only one wiper 30 is shown in FIG. 4, four wipers 30 are provided for each of the four heads 2, and a total of four wipers arranged in parallel along the direction perpendicular to the paper surface of FIG. 30 is supported (see FIG. 5A). The wiper 30 is made of a flexible material such as urethane rubber, and is a plate-like member having a width substantially the same as the width of the ink ejection surface 2b of the head 2 (the length in the direction perpendicular to the paper surface of FIG. 4). . The lower end of each wiper 30 is fixed to the base surface of the frame 31, and a back surface (a surface not facing the head 2 in FIG. 4) in the wipe direction described later is erected so as to form an acute angle θ with respect to the base surface. Yes. The frame 31 is moved together with the four wipers 30 in a longitudinal direction and a vertical direction (a direction perpendicular to the ink ejection surface 2b) of the ink ejection surface 2b by a driving mechanism 80 (see FIG. 5A) described later.

  One end of a tube 61 is inserted into the side surface of the frame 31, and ink collected in the frame 31 by wiping is collected in a waste ink reservoir 60 via the tube 61.

  At the time of the printing operation, as shown in FIG. 4, the belt conveyance mechanism 13 is a conveyance position where the ink ejection surface 2b of the head 2 and the upper loop surface of the conveyance belt 8 face each other with a small gap, and the wiper 30 is shown in FIG. It is arranged at a standby position on the back side of the belt conveyance mechanism 13.

  On the other hand, when wiping is performed, the belt conveyance mechanism 13 is moved downward (in the direction of the white arrow in FIG. 4) from the conveyance position by the elevating mechanism and stops at the non-conveyance position. Here, the non-conveying position means a position where a sufficient space that does not interfere with the wiper 30 and the frame 31 during wiping is formed between the ink ejection surface 2 b and the upper loop surface of the conveying belt 8. The wiper 30 moves horizontally from the standby position in the direction approaching the head 2 (in the direction of the black arrow in FIG. 4) from the standby position after the belt conveyance mechanism 13 is lowered and stopped at the non-conveyance position. Wiping is performed when printing on a predetermined number of sheets is completed.

  Next, the drive mechanism 80 that drives the wiper 30 will be described with reference to FIGS. 5, 6, and 7.

  As shown in FIG. 5A, the drive mechanism 80 includes two guide bars 70 extending along the longitudinal direction of the head body 2a (the direction perpendicular to the paper surface of FIG. 1), Two timing belts 71 extending in parallel are included. The guide bars 70 are respectively arranged on the sides of the head main body 2a located at both ends so as to sandwich the four head main bodies 2a in plan view. Both ends of each guide bar 70 are fixed to guide holders 74 and 75 (see FIGS. 5B and 5C). The shafts 76 and 77 are inserted through the guide holders 74 and 75, respectively. However, the guide holders 74 and 75 do not rotate as the shafts 76 and 77 rotate.

  The shafts 76 and 77 extend in a direction orthogonal to the guide bar 70 and the timing belt 71, and both ends thereof are rotatably supported by the printer 1 main body. A pair of pulleys 72 a and 72 b are fixed in the vicinity of both ends of the shafts 76 and 77. Each of the timing belts 71 is an endless belt, and is wound around pulleys 72a and 72b facing each other in the left-right direction in FIG. 5A and is stretched between the pulleys 72a and 72b. As shown in FIG. 5D, the frame 31 that supports the wiper 30 is fixed to the timing belt 71 and slidably supported on the guide bar 70.

  A scanning gear 73 is fixed to the shaft 76, and the scanning gear 73 rotates in the forward and reverse directions when the drive motor 40 is driven under the control of the controller 50 (see FIG. 4). As the scanning gear 73 rotates, both the shaft 76 and the pulley 72a rotate. That is, since the scanning gear 73, the shaft 76, and the pulley 72a are fixed to each other, they rotate simultaneously. As a result, the timing belt 71 wound around the pulley 72 a travels, and the pulley 72 b rotates with the shaft 77 as the timing belt 71 travels. As the timing belt 71 travels, the frame 31 moves in the left-right direction in FIG. 5A, that is, in the longitudinal direction of the ink ejection surface 2b.

  Both ends of the shaft 77 are inserted into a groove 81 formed in the main body of the printer 1 (see FIGS. 7A and 7B), and both ends of the shaft 77 swing when moved in the groove 81. It has become. The groove 81 has an arc shape with the shaft 76 as the center.

  As shown in FIGS. 6A and 6B, one end surface of the guide bar holder 75 has an arc shape centered on the shaft 76, and teeth that mesh with the gear 79 are formed on the end surface. The gear 79 has a shaft 78 that is rotatably attached to the main body of the printer 1 as an axis, and rotates together with the shaft 78. The shaft 78 rotates in the forward and reverse directions when the drive motor 41 is driven by the control of the controller 50 (see FIG. 4). As a result, the gear 79 rotates, and the guide bar holder 75 engaged with the teeth of the gear 79 swings together with the shaft 77.

  For example, when the gear 79 rotates counterclockwise from the state shown in FIG. 6A, the guide bar holder 75 swings downward together with the shaft 77 as shown in FIG. FIGS. 7A and 7B show the position of the shaft 77 with respect to the groove 81 in the state shown in FIGS. 6A and 6B, respectively.

  As described above, the frame 31 can move in the left-right direction of FIG. 5A, that is, the longitudinal direction of the ink discharge surface 2b as the timing belt 71 travels, and the shaft 77 and the guide bar holder 75 swing. Along with the movement, it is movable in a direction perpendicular to the paper surface of FIG. 5A, that is, a direction orthogonal to the ink ejection surface 2b.

  Next, the operation of the wiper 30 during wiping will be described. The operation of the wiper 30 described below is controlled by the controller 50 in FIG. 4 and realized by the drive mechanism 80 described above.

  The wiper 30 first moves horizontally from the standby position along the black arrow direction in FIG. 4 along the longitudinal direction of the head 2. The moving direction at this time is referred to as a wipe direction, and the surface in front of the wipe direction in the plate-like wiper 30 is referred to as a front surface, and the opposite surface is referred to as a back surface. When the front end of the wiper 30 comes into contact with the corner of the L-shaped support 15a (on the left side in FIG. 4) closer to the standby position of the wiper 30 in the holder 15, the upper end of the wiper 30 bends in the direction opposite to the wipe direction. The wiper 30 moves in the wiping direction with the upper end bent in this way.

  As shown in FIG. 8A, the upper end of the wiper 30 reaches one end in the longitudinal direction of the ink ejection surface 2b of the head main body 2a (left side in FIG. 8A), and the wiper 30 is further bent at the upper end. Move in the wipe direction. The operation at this time is referred to as wiping, and the ink adhering to the ink discharge surface 2b is wiped off from the ink discharge surface 2b and held between the front surface of the bent upper end of the wiper 30 and the ink discharge surface 2b. The

  The wiper 30 has its upper end closest to the other end in the longitudinal direction of the ink ejection surface 2b (right side in FIG. 8A), more specifically, the other end in the longitudinal direction of the ink ejection surface 2b and the other end. When it reaches a position between the nozzle opening 28 (see FIG. 3), the upper end is bent and the ink discharge surface 2b is kept in contact with the ink discharge surface 2b for 2 to 3 seconds. During this stop, the ink held between the front surface of the bent upper end of the wiper 30 and the ink discharge surface 2 b gradually moves downward along the wiper 30.

  After a lapse of 2-3 seconds, the wiper 30 moves downward together with the frame 31 and is separated from the ink ejection surface 2b and returns elastically. At this time, a very small amount of ink retained between the front surface of the wiper 30 near the bent upper end and the ink ejection surface 2b remains on the ink ejection surface 2b, and most of the other ink is retained on the wiper 30. Gradually move down along the front and back of the. The ink that has reached the lower end of the wiper 30 and has accumulated in the frame 31 is collected in the waste ink reservoir 60 via the tube 61 of FIG.

  Thereafter, as shown in FIG. 8B, the wiper 30 moves in the wipe direction while being separated from the ink ejection surface 2b, and stops at a position beyond the ink absorber 16 in the horizontal direction. The wiper 30 moves upward, and stops at a position where the upper end of the wiper 30 exceeds the lower surface of the ink absorber 16, more specifically, slightly above in the vertical direction than during wiping. Next, as shown in FIG. 8C, the wiper 30 moves in the reverse direction of the wipe direction, the back surface near the upper end thereof contacts the ink absorber 16, and the vicinity of the upper end bends in the wipe direction. The amount of deflection of the wiper 30 at this time is larger than the amount of deflection during wiping because the position in the vertical direction is slightly above that during wiping as described above. In addition, when the ink absorber 16 and the back surface of the wiper 30 are brought into contact with each other in this manner, the ink adhering to the back surface of the wiper 30 is absorbed by the ink absorber 16 and the back surface of the wiper 30 has no ink attached thereto. It becomes.

  Next, the wiper 30 stops when the upper end of the wiper 30 reaches the L-shaped support portion 15a of the holder 15 on the right side of FIG. 8 (c), and then moves downward and is separated from the L-shaped support portion 15a to return elastically. To do. The wiper 30 moves in the reverse direction of the wipe direction while being separated from the right L-shaped support portion 15a and the ink ejection surface 2b in FIG. 8C, and its upper end slightly exceeds the wipe end position in the horizontal direction. It stops at the position, and then moves upward slightly downward in the vertical direction as compared with the wiping shown in FIG. 8A (see FIG. 8C).

  As shown in FIG. 8D, the vicinity of the upper end of the wiper 30 comes into contact with the ink ejection surface 2b again and bends in the direction opposite to the wipe direction, and the wiper 30 moves in the wipe direction in this state. This operation is referred to as re-wiping, and the moving speed of the wiper 30 at this time is smaller than the moving speed at the time of wiping shown in FIG. Further, the amount of bending of the wiper 30 at this time is smaller than the amount of bending at the time of wiping because the position in the vertical direction is slightly lower than that at the time of wiping as described above. In re-wiping, the wiper 30 stops immediately before the other longitudinal end of the ink discharge surface 2b, moves downward, moves away from the ink discharge surface 2b, and further wipes to the position where the upper end reaches below the ink absorber 16. Move to.

  When the upper end of the wiper 30 reaches below the ink absorber 16, the wiper 30 stops and then moves upward toward the ink absorber 16. Then, the front surface near the upper end of the wiper 30 contacts the ink absorber 16, and the vicinity of the upper end bends in the direction opposite to the wipe direction. In this state, the wiper 30 moves in the wiping direction to a position where the upper end of the wiper 30 elastically returns beyond the ink absorber 16 as shown in FIG. By this movement, the ink adhering to the front surface of the wipe 30 is absorbed by the ink absorber 16, and the front surface of the wiper 30 is in a state where no ink is adhering.

  As described above, according to the present embodiment, when the wiper 30 is separated from the ink discharge surface 2b, most of the ink scraped by wiping as shown in FIG. 8B is in the longitudinal direction of the ink discharge surface 2b. Since the ink does not enter between the other end and the L-shaped support portion 15 a and is separated from the ink discharge surface 2 b together with the wiper 30 while being held by the wiper 30, almost no ink remains in the head 2. Therefore, the problem that the inside of the printer 1 is contaminated with ink by wiping can be reduced.

  The head 2 has a length equal to or larger than the width of the paper as a recording medium and is relatively long. Therefore, the wiper 30 is moved along the longitudinal direction of the head 2 in wiping as shown in FIG. Then, a large amount of ink is scraped up by the wiper 30. Even in such a case, by separating the wiper 30 between the other longitudinal end of the ink discharge surface 2b and the nozzle opening 28 closest to the other end, for example, the wiper 30 can move the other end of the ink discharge surface 2b. The above problem that the inside of the printer 1 is contaminated with ink due to the scattering of the ink when returning to elasticity beyond the range can be reduced.

  The entire surface of the ink discharge surface 2b is subjected to water repellent treatment, and other portions of the head main body 2a are not subjected to water repellent finish. Therefore, the ink adhesion performance is small over the entire area of the ink ejection surface 2b, and is relatively large in other portions. Therefore, the ink adhering performance is changed so that the ink adhering performance is increased at the other end in the longitudinal direction of the ink ejecting surface 2b, more specifically, at the boundary between the ink ejecting surface 2b and the side surface of the head body 2a facing the tip of the L-shaped support portion 15a. To do. That is, in the present embodiment, the other end in the longitudinal direction of the ink ejection surface 2b corresponds to “a change position where the ink adhesion performance changes so as to increase” in the present invention. In such a case, if the wiper 30 is moved to the other end in the longitudinal direction of the ink discharge surface 2b during wiping, the ink easily enters the gap between the head 2 and the L-shaped support portion 15a of the holder 15. However, in this embodiment, the wiper 30 is separated from the ink discharge surface 2b before the other end in the longitudinal direction of the ink discharge surface 2b, thereby effectively preventing ink from entering the gap between the head 2 and the holder 15. Can do.

  Note that the entire surface of the ink ejection surface 2b is water-repellent, and the wiper 30 is separated from the ink ejection surface 2b in the water-repellent region, so that the ink scraped by wiping moves smoothly to the wiper 30. Almost no ink remains on the ink ejection surface 2b. Thereby, the problem that the inside of the printer 1 is contaminated with ink can be more reliably reduced.

  The holder 15 is provided with a pair of L-shaped support portions 15a for supporting one end and the other end in the longitudinal direction of the ink ejection surface 2b of each head 2, and supports the other end in the longitudinal direction of the ink ejection surface 2b. A portion of the L-shaped support portion 15a adjacent to the other end has a round shape. For example, when the portion of the holder 15 is not a round shape but an angular shape, the gap between the head 2 and the portion of the holder 15 becomes small, so that the ink easily enters the gap due to capillary action. By making the portion into a round shape, the gap can be further widened and ink can be effectively prevented from entering the gap between the head 2 and the holder 15.

  As shown in FIG. 8B, most of the ink collected by wiping is stopped by stopping the wiper 30 for 2 to 3 seconds while keeping the wiper 30 in contact with the ink ejection surface 2b immediately before separating the wiper 30 from the ink ejection surface 2b. Moves from the ink discharge surface 2b to the wiper 30, so that almost no ink remains on the ink discharge surface 2b. Thereby, it is possible to more effectively prevent the inside of the printer 1 from being contaminated with ink.

  The ink absorber 16 is provided in the printer 1, and the ink adhering to the wiper 30 is brought into contact with the ink absorber 16 by bringing the wiper 30 separated from the ink ejection surface 2b into the ink absorber as shown in FIG. The ink adhering to the wiper 30 can be removed by being absorbed by 16.

  The ink adhering to the wiper 30 after wiping is removed by the ink absorber 16, and then rewiping is performed as shown in FIG. 8D. By wiping the ink discharge surface 2b again in this way, it is possible to remove ink that remains slightly on the ink discharge surface 2b after the initial wiping.

  As shown in FIG. 8B, when the wiper 30 is separated from the ink ejection surface 2b, the ink tends to adhere to the back surface of the wiper 30. If the wiper 30 is brought into contact with the ink ejection surface 2b again in such a state, the ink adhering to the back surface of the wiper 30 tends to adhere to the ink ejection surface 2b. However, as shown in FIG. Such problems can be suppressed by removing the ink adhering to the back surface of the wiper 30 by the ink absorber 16 before performing the operation.

  By making the movement speed of the wiper 30 in the wipe direction smaller at the time of rewiping than at the time of initial wiping, even if the wiper 30 reaches the other end in the longitudinal direction of the ink ejection surface 20 at the time of rewiping. Thus, it is difficult for the ink thus collected to enter the gap between the head 2 and the holder 15 or to be scattered.

  After rewiping after the first wiping is completed, the ink adhering to the wiper 30 is absorbed by the ink absorber 16 and removed, as shown in FIG. Thereby, the next wiping can be performed in a state where almost no ink is attached to the wiper 30.

  Since the ink absorber 16 is held by the L-shaped support portion 15a that supports the other longitudinal end of the ink discharge surface 2b (right side in FIG. 4) of the holder 15, the ink absorber 16 is placed near the ink discharge surface 2b. The wiper 30 can be efficiently moved in a short time when the ink is removed from the wiper 30 using the ink absorber 16 shown in FIGS. 8C and 8D.

  The wiper 30 has flexibility, and the deflection amount of the wiper 30 is adjusted by changing the position of the wiper 30 in the vertical direction. By setting the amount of deflection of the wiper 30 to an amount suitable for the purpose, each operation such as wiping, rewiping, and ink removal from the wiper 30 by the ink absorber 16 can be performed efficiently. Specifically, by making the deflection of the wiper 30 smaller at the time of rewiping than at the time of wiping, it is possible to effectively suppress ink scattering due to elastic recovery of the wiper 30 at the end of rewiping. In addition, by increasing the deflection of the wiper 30 when the ink absorber 16 absorbs the ink more than at the time of wiping, the ink can be efficiently removed from the wiper 30 and remains on the ink ejection surface 2b in the subsequent rewiping. Ink can be removed more reliably.

  Next, a modification of the ink absorber according to the present invention will be described with reference to FIGS.

  In the first modification shown in FIG. 9, unlike the ink absorber 16 of the above embodiment, an ink absorber 116 having a cylindrical shape is applied. The ink absorber 116 is not held by the L-shaped support portion 15a that supports the other end in the longitudinal direction of the ink discharge surface 2b of the holder 15, and a slight gap is provided on the side of the L-shaped support portion 15a. Are arranged. The ink absorber 116 is connected to the rotation motor 140 and rotates about the central axis 116 a by driving the rotation motor 140. The rotation motor 140 is connected to the controller 50. For example, after the wiping is performed several times, the controller 50 drives the rotation motor 140 to rotate the ink absorber 116 about the central axis 116a. Ink existing in the ink absorber 116 is scraped out by a scraper 117 arranged so that the tip abuts against the peripheral surface of the ink absorber 116.

  In the same manner as shown in FIGS. 8C and 8D, when the upper end of the wiper 30 is brought into contact with the ink absorber 116, the ink is held in the ink absorber 116. There is usually a limit to the amount of ink retained by the ink absorber 116, and if a certain amount of ink is retained, the absorbing power may be reduced. Therefore, in this modification, the ink absorbing power of the ink absorber 116 can be maintained in a good state by removing the ink present in the ink absorber 116 with the scraper 117.

  In the second modification shown in FIG. 10, the ink absorber 216 is held by the scraper 217. The ink absorber 216 and the scraper 217 are not held by the L-shaped support portion 15a that supports the other longitudinal end of the ink discharge surface 2b of the holder 15 as in the modification of FIG. It is arranged on the side of the portion 15a with a slight gap. The scraper 217 has an inverted T shape composed of a shaft portion and a base portion that hold the ink absorber 216 on both sides, and both ends of the base portion are sharpened upward. The vicinity of the sharp tip of the scraper 217 is exposed without holding the ink absorber 216.

  In this modification, when the ink attached to the wiper 30 is removed, the front or back surface of the wiper 30 is brought into contact with the sharp tip of the scraper 217, and the vicinity of the upper end of the wiper 30 is bent. For example, when ink adhering to the wiper 30 after the initial wiping shown in FIG. 8C is absorbed by the ink absorber 216, the back surface of the wiper 30 is brought into contact with the right end at the base of the scraper 217 in FIG. Alternatively, after the rewiping shown in FIG. 8D, the front surface of the wiper 30 is brought into contact with the left end of the base of the scraper 217 in FIG. By moving the wiper 30 in such a manner that the wiper 30 is brought into contact with the tip of the scraper 217 and rubbed, the ink adhering to the wiper 30 is removed by the scraper 217, moves to the upper surface of the base of the scraper 217, and enters the ink absorbent 217 Absorbed.

  According to the modification shown in FIG. 10, it is possible to prevent the ink absorber 216 from being deteriorated due to friction or the like, and to avoid a situation in which ink or foreign matter attached to the ink absorber 216 adheres to the wiper 30. it can.

  The preferred embodiments of the present invention have been described above, but the present invention is not limited to the above-described embodiments, and various design changes can be made as long as they are described in the claims.

  For example, the position at which the wiper 30 is separated from the ink discharge surface 2b at the end of the initial wiping is between the other end in the longitudinal direction of the ink discharge surface 2b and the nozzle opening 28 closest to the other end as in the above-described embodiment. It is not limited to. In the above-described embodiment, the other end in the longitudinal direction of the ink discharge surface 2b corresponds to the “change position where the ink adhesion performance changes so as to increase” in the present invention. However, for example, when the water-repellent processing in the vicinity of the other end in the longitudinal direction of the ink ejection surface 2b is omitted, the non-water-repellent processing region formed by omitting the water-repellent processing has a relatively large ink adhesion performance. The boundary with the non-water repellent region corresponds to the change position. In such a case, the position where the wiper 30 is separated from the ink ejection surface 2b after the completion of the first wiping is defined as the water repellent region and the non-repellent region. It may be in the water repellent region between the boundary of the water processing region and the nozzle opening 28 closest to the other end. As described above, the “change position at which the ink adhesion performance changes” may be determined by various factors. The “change position” is a position at which the wiper 30 is separated from the ink ejection surface 2b at the end of the initial wiping. Is defined.

  In the above-described embodiment, the head 2 is fixed and the wiper 30 is moved with respect to the head 2. However, the relative positional relationship of the wiper 30 with respect to the head 2 may be changed, and the wiper 30 is fixed. The head 2 may be moved with respect to the wiper 30.

  One wiper 30 in the above-described embodiment is provided for each head 2, but two or more may be provided for each head 2, or a common one may be provided for the four heads 2. Good. Further, the shape of the wiper 30 is not limited to a plate shape.

  Wiping may be performed by moving the wiper 30 not in the longitudinal direction of the head 2 but in the width direction.

  A portion of the holder 15 that is close to the other end of the L-shaped support portion 15a that supports the other end of the ink discharge surface 2b is not limited to a round shape, and may be, for example, a shape inclined with respect to the ink discharge surface 2b. Good.

  One ink absorber 16, 116, 216 may be provided for each head 2, that is, one for each wiper 30, or one for four heads 2, ie, for four wipers 30. One may be provided. The ink absorbers 16, 116, and 216 may be made of various materials other than urethane as long as they can absorb ink, and the shapes thereof may be various without being limited to the above-described embodiments and modifications. The ink absorbers 16, 116, and 216 are not limited to be held by the L-shaped support portion 15 a that supports the other end of the ink discharge surface 2 b of the holder 15, or are disposed adjacent to the side thereof. It can be arranged at various positions within.

  The ink absorbers 16, 116, 216 may be omitted. In this case, the operation of causing the ink absorbers 16, 116, 216 to absorb the ink adhering to the wiper 30 (see FIGS. 8C and 8D) is not performed.

  Ink absorber 16, 116, 216 absorbs ink adhering to the back surface of wiper 30 before rewiping, and ink adhering to wiper 30 after rewiping is performed by ink absorber 16. , 116, 216 may be omitted.

  It is not limited to controlling the amount of deflection of the wiper 30 to change, and the amount of deflection may be controlled to be constant.

  The moving speed of the wiper 30 in the wiping direction is not limited to lowering at the time of rewiping than at the time of the initial wiping. For example, the moving speed may be constant.

  The present invention is not limited to the line type, and can also be applied to a serial type printer. In addition to a printer, the present invention can also be applied to a recording apparatus such as a facsimile or a copier.

1 is a front view of an ink jet printer according to an embodiment of the present invention. FIG. 2 is a plan view of one of the four ink jet heads shown in FIG. 1. It is a fragmentary sectional view of an inkjet head. FIG. 2 is a side view of the ink jet printer as viewed from the left side of FIG. 1. (A) is a top view which shows the drive mechanism which drives a wiper contained in an inkjet printer. (B) is the side view which looked at the drive mechanism from the arrow B direction of (a). (C) is the side view which looked at the drive mechanism from the arrow C direction of (a). (D) is sectional drawing along the DD line of (a). It is the side view which looked at the drive mechanism from the arrow VI direction of Fig.5 (a). (A), (b) is the schematic which shows the position of the shaft of the drive mechanism in the state shown to Fig.6 (a), (b), respectively. It is explanatory drawing which shows operation | movement of the wiper at the time of wiping. It is the schematic which shows the 1st modification of an ink absorber. It is the schematic which shows the 2nd modification of an ink absorber.

Explanation of symbols

1 Inkjet printer (inkjet recording device)
2 Inkjet head 2b Ink ejection surface 15 Holder 16 Ink absorber 28 Nozzle opening 30 Wiper 31 Frame (wiper holder, slide mechanism)
40 Drive motor (first drive source)
41 Drive motor (second drive source)
50 controller (wiping control means, absorber rotation control means)
70 Guide bar (guide, slide mechanism)
71 Timing belt (endless belt, slide mechanism)
72a, 72b Pulley (slide mechanism)
75 Guide bar holder (first gear, gear mechanism)
76 shaft (first and second shafts, slide mechanism)
77 Shaft (slide mechanism)
79 Gear (second gear, gear mechanism)
80 Drive Mechanism 116 Ink Absorber 117 Scraper 140 Rotation Motor (Rotation Drive Mechanism)
216 Ink absorber 217 Scraper

Claims (19)

An inkjet head having an ink ejection surface in which openings of a plurality of nozzles for ejecting ink are formed;
A wiper for wiping off ink adhering to the ink ejection surface;
A drive mechanism for driving at least one of the inkjet head and the wiper;
The wiper is moved relative to the inkjet head in a wiping direction from one end of the ink discharge surface to the other end while being in contact with the ink discharge surface, and the opening of the nozzle closest to the other end and the opening Wiping for controlling the drive mechanism so as to separate the wiper from the ink ejection surface between the first end and the other end and a change position where the ink adhesion performance changes in the wiping direction. Control means;
An ink jet recording apparatus comprising: The ink ejection surface is water repellent,
The inkjet recording apparatus according to claim 1, wherein the wiping control unit separates the wiper from the ink discharge surface in the region where the water repellent process is performed. The inkjet head has a length equal to or greater than the width of the recording medium;
3. The ink jet recording apparatus according to claim 1, wherein the wiping control unit controls the driving mechanism so as to relatively move the wiper along a longitudinal direction of the ink jet head. A holder for holding the inkjet head by supporting the one end and the other end of the ink ejection surface of the inkjet head;
The inkjet recording apparatus according to claim 1, wherein the change position is the other end of the ink ejection surface. The holder has an end support portion that supports the one end of the ink discharge surface of the inkjet head and another end support portion that supports the other end,
The inkjet recording apparatus according to claim 4, wherein a portion of the other end support portion that is close to the other end of the ink discharge surface has a rounded shape.   2. The wiping control unit controls the drive mechanism so that the wiper stops for a predetermined time while being in contact with the ink discharge surface immediately before the wiper is separated from the ink discharge surface. The inkjet recording apparatus as described in any one of -5.   A first driving source that applies a driving force to the driving mechanism so that the wiper moves relative to the inkjet head along the wiping direction; and the wiper moves in a direction intersecting the ink ejection surface. The ink jet recording apparatus according to claim 1, wherein a second driving mechanism that applies a driving force to the driving mechanism is provided separately. The drive mechanism includes a slide mechanism that moves the wiper along the wipe direction, and a gear mechanism that moves the wiper in a direction intersecting the ink ejection surface;
The slide mechanism includes a wiper holder that supports the wiper, a guide that supports the wiper holder so as to be slidable along the wipe direction, and a first and a second that are spaced apart with respect to the wipe direction so as to sandwich the inkjet head. A pulley fixed to each of the first and second shafts, and an endless belt wound around the pulley and stretched between the pulleys and to which the wiper holder is fixed, When the first shaft is rotated by the driving force of the first driving source, one of the pulleys and a pulley fixed to the first shaft rotates, and the belt travels, so that the wiper holder Slide in the wipe direction while being supported by the guide,
The gear mechanism includes a first gear rotatably attached to the second shaft and having the guide fixed thereto, and a second gear, and the first gear is the first shaft. When the second gear is rotated by the driving force of the second drive source, the second gear is meshed with the one end surface. The shaft and the first gear move along an arc shape centered on the first shaft, and the wiper holder supported by the guide moves in a direction intersecting the ink ejection surface. The ink jet recording apparatus according to claim 7. An ink absorber,
The said wiping control means controls the said drive mechanism so that the ink adhering to the said wiper spaced apart from the said ink discharge surface may be absorbed by the said ink absorber. The ink jet recording apparatus according to any one of claims.   The wiping control unit is configured to move the wiper in the wiping direction while contacting the ink ejection surface from the vicinity of the separation position from the ink ejection surface after the ink absorber has absorbed the ink adhering to the wiper. The ink jet recording apparatus according to claim 9, wherein the driving mechanism is controlled so as to be relatively moved.   The wiping control means is configured so that the ink adhering to the back surface in the wipe direction in the wiper after the wiper is separated from the ink discharge surface and before coming into contact with the ink discharge surface again. The inkjet recording apparatus according to claim 10, wherein the drive mechanism is controlled so as to be absorbed by the ink.   The wiping control means is configured such that the wiper moving speed in the wiping direction after contacting the ink ejection surface again after being separated from the ink ejection surface is the wiper in the wiping direction before being separated from the ink ejection surface. The inkjet recording apparatus according to claim 10 or 11, wherein the driving mechanism is controlled so as to be smaller than a moving speed of the ink jet recording apparatus.   The wiping control means is configured such that after the wiper is separated from the ink ejection surface and again comes into contact with the ink ejection surface and further moves relative to the wipe direction, the ink adhering to the wiper is absorbed by the ink absorber. The inkjet recording apparatus according to any one of claims 10 to 12, wherein the drive mechanism is controlled as described above.   The said ink absorber is hold | maintained at the other end support part which supports the said other end of the said ink discharge surface in the holder holding the said inkjet head. The ink jet recording apparatus described. The wiper has flexibility;
The ink jet recording apparatus according to claim 10, wherein the wiping control unit controls the driving mechanism so that a deflection amount of the wiper is changed.   The wiping control means is configured so that the amount of flexure of the wiper is smaller after contacting the ink ejection surface again after being separated from the ink ejection surface than before being separated from the ink ejection surface. The inkjet recording apparatus according to claim 15, wherein the inkjet recording apparatus is controlled.   In the wiping control means, the deflection amount of the wiper is more when the ink adhering to the wiper separated from the ink ejection surface is absorbed by the ink absorber than before the separation from the ink ejection surface. The ink jet recording apparatus according to claim 15, wherein the driving mechanism is controlled to be large. The ink absorber has a cylindrical shape;
A rotation drive mechanism for rotating the ink absorber around a central axis;
A scraper having a tip contacting the peripheral surface of the ink absorber;
The inkjet recording apparatus according to claim 9, further comprising an absorber rotation control unit that controls the rotation driving mechanism so that the ink absorber rotates. A scraper for holding the ink absorber;
The tip of the scraper is exposed,
The wiping control means controls the drive mechanism so that the ink adhering to the wiper is absorbed by the ink absorber through the scraper when the wiper contacts the tip of the scraper. The ink jet recording apparatus according to claim 9, wherein the ink jet recording apparatus is an ink jet recording apparatus.

Images