JP5953749B2 - Liquid ejection device - Google Patents

Description

  The present invention relates to a liquid ejection apparatus having a plurality of ejection ports for ejecting liquid.

  Patent Document 1 is known as a technical document related to a liquid ejection apparatus. Patent Document 1 discloses a technique of cleaning a nozzle surface 8a using three wiper blades 4a, 4b, and 4c in an inkjet printer.

Japanese Utility Model Publication No. 8-867 (FIG. 1)

  However, according to Patent Document 1, each of the three wiper blades 4a, 4b, and 4c (wiper) comes into contact with substantially the entire nozzle surface 8a (discharge surface). Therefore, the discharge region (region where a plurality of discharge ports are opened) can be damaged. In particular, when a water-repellent film is formed on the periphery of the discharge port, each of the plurality of wipers may come into contact with the discharge region, causing a problem that the water-repellent film is peeled off and the discharge performance is deteriorated. .

  An object of the present invention is to provide a liquid ejection apparatus capable of reliably removing foreign matter on the ejection surface while suppressing damage to the ejection area.

In order to achieve the above object, according to an aspect of the present invention, a liquid discharge head having a discharge surface including a discharge region in which a plurality of discharge ports for discharging liquid are opened and a non-discharge region in which the discharge ports are not open A wiper unit including a first wiper and a second wiper for removing foreign matter on the discharge surface by moving relative to the discharge surface while being in contact with the discharge surface, respectively, and the discharge surface Moving means for moving the first wiper and the second wiper relative to each other, and the first wiper is disposed downstream of the second wiper in the moving direction of the moving means. A first abutting portion that abuts at least the entire area of the ejection region of the ejection surface, and the second wiper abuts at least a portion of the non-ejection region that does not abut the first abutting portion. contact One said a second contact portion which is not discharged area contact and, that with respect to direction orthogonal to the moving direction parallel to the discharge surface having a second contact portion which overlaps with the first contact portion A liquid ejection device is provided.

  According to the present invention, after at least foreign matter on the ejection region is removed by the first wiper, foreign matter that could not be removed by the first wiper is removed by the second wiper. Further, since the second wiper does not come into contact with the discharge area, damage to the discharge area can be suppressed. That is, according to the present invention, it is possible to reliably remove foreign matters on the ejection surface while suppressing damage to the ejection region.

1 is a schematic side view showing an internal structure of an ink jet printer according to an embodiment of the present invention. It is a top view which shows the flow-path unit contained in the inkjet head of the printer of FIG. FIG. 3 is an enlarged view showing a region III surrounded by an alternate long and short dash line in FIG. 2. FIG. 4 is a partial cross-sectional view taken along line IV-IV in FIG. 3. FIG. 2 is a partial plan view of the printer of FIG. 1 and shows a wiper unit provided for each head. It is a perspective view which shows 1 wiper unit. It is a perspective view which shows the assembly | attachment process of the 1st wiper of a wiper unit, and a 2nd wiper. (A) is sectional drawing which followed the VIIIA-VIIIA line | wire of FIG.7 (d). (B) is sectional drawing along the VIIIB-VIIIB line which passes along the center of protrusion of FIG.7 (d). (A) is sectional drawing which followed the IXA-IXA line | wire of FIG. 5 which shows the condition where wiping is performed. FIG. 9B is an enlarged view showing a region IXB surrounded by a one-dot chain line in FIG. FIG. 2 is a block diagram illustrating an electrical configuration of the printer of FIG. 1.

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

  First, an overall configuration of an ink jet printer 1 according to an embodiment of the present invention will be described with reference to FIG.

  The printer 1 is a line type color ink jet printer. The printer 1 has a rectangular parallelepiped casing 1a. A paper discharge unit 31 is provided on the top of the casing 1a. The internal space of the housing 1a can be divided into three spaces A, B, and C in order from the top. Spaces A and B are spaces in which a paper transport path that continues to the paper discharge unit 31 is formed. In the space A, conveyance of the paper P and image formation on the paper P are performed. In the space B, an operation related to paper supply is performed. In the space C, a cartridge 39 as an ink supply source is accommodated.

  In the space A, four inkjet heads 10, a wiper unit 40 (described later, see FIG. 5 and the like) provided for each head 10, a transport unit 21 that transports the paper P, a guide member that guides the paper P, and the like are arranged. ing. In the upper part of the space A, a controller 1p that controls the operation of each part of the printer 1 and controls the operation of the entire printer 1 is disposed.

  The four heads 10 have a substantially rectangular parallelepiped shape that is long in the main scanning direction. The heads 10 are arranged at a predetermined pitch in the sub-scanning direction and are supported by the housing 1a via the frame 3. The frame 3 is movable in the vertical and main scanning directions while supporting the four heads 10 by driving a head moving motor 10M (see FIG. 10) under the control of the controller 1p. The head 10 includes a flow path unit 12, eight actuator units 17, and a reservoir unit 11. The lower surface of the head 10 (the lower surface of the flow path unit 12) is a discharge surface 10x having a large number of discharge ports 14a (see FIG. 4). Ink is ejected from the ejection port 14a onto the conveyed paper P. Magenta, cyan, yellow, and black inks are ejected from the four heads 10, respectively.

  A hydrophilic member (such as an adhesive or a sealant) is provided around the discharge surface 10x. The member may have a function of joining the head 10 and the frame 3 to each other, a function of filling a gap formed between the head 10 and the frame 3, and the like.

  The transport unit 21 includes a pressing roller 4, a peeling plate 5, two belt rollers 6 and 7, and an endless transport belt 8 wound between the rollers 6 and 7. The belt roller 7 is a driving roller, and rotates clockwise in FIG. 1 by driving the transport motor 21M (see FIG. 10) under the control of the controller 1p. As the belt roller 7 rotates, the conveyor belt 8 travels in the direction of the arrow in FIG. The belt roller 6 is a driven roller and rotates clockwise in FIG. 1 as the transport belt 8 travels.

  A plate-shaped platen 19 is disposed in the loop of the conveyor belt 8 so as to face the ejection surfaces 10 x of the four heads 10. The upper loop of the conveyor belt 8 is supported by the platen 19 from the inner peripheral surface side, and a gap suitable for image formation is formed between the outer peripheral surface 8a and the ejection surface 10x.

  A weak adhesive silicon layer is formed on the outer peripheral surface 8 a of the conveyor belt 8. The paper P sent to the transport unit 21 is pressed by the pressing roller 4 and held on the outer peripheral surface 8a, and is transported in the sub-scanning direction along the black arrow.

  The paper P is peeled off from the outer peripheral surface 8a by the peeling plate 5 on the right side in FIG. The peeled paper P is conveyed upward by the two pairs of feed rollers 28 along the guides 29a and 29b, and is discharged from the opening 30 at the top of the housing 1a to the paper discharge unit 31. One roller of each pair of feed rollers 28 is rotated by driving a feed motor 28M (see FIG. 10) under the control of the controller 1p.

  In the space B, the paper feeding unit 1b is detachably arranged with respect to the housing 1a. The paper feeding unit 1b is attached and detached along the main scanning direction. As shown in FIG. 1, the paper feed unit 1 b includes a paper feed tray 23 that stores the paper P, and a paper feed roller 25 attached to the paper feed tray 23. The paper feed tray 23 is a box that opens upward, and can store a plurality of types of paper P. The paper feed roller 25 is rotated by the drive of a paper feed motor 25M (see FIG. 10) under the control of the controller 1p, and feeds the paper P at the uppermost position of the paper feed tray 23. The paper P sent out by the paper feed roller 25 is sent to the transport unit 21 by the feed roller pair 26 along the guides 27a and 27b. One roller of the feed roller pair 26 is also rotated by driving the feed motor 26M (see FIG. 10) under the control of the controller 1p. As described above, a paper conveyance path along the thick arrow shown in FIG. 1 is formed in the printer 1 from the paper supply unit 1 b toward the paper discharge unit 31.

  Here, the sub-scanning direction is a direction parallel to the transport direction of the paper P by the transport unit 21, and the main scanning direction is a direction perpendicular to the sub-scanning direction and along the horizontal plane. Both the main scanning direction and the sub-scanning direction are parallel to the horizontal plane (the ejection surface 10x of the head 10) and orthogonal to the vertical plane.

  In the space C, the ink unit 1c is detachably arranged with respect to the housing 1a. The ink unit 1c is attached and detached along the main scanning direction. The ink unit 1 c includes a tray 35 and four cartridges 39. The four cartridges 39 store magenta, cyan, yellow, and black inks, respectively. Each cartridge 39 is accommodated in the tray 35 and arranged in parallel in the sub-scanning direction.

  The controller 1p disposed in the space A includes a CPU (Central Processing Unit) which is an arithmetic processing unit, a program executed by the CPU and a ROM (Read Only Memory) in which data used for the program is stored, and data when the program is executed. RAM (Random Access Memory) for temporarily storing data, an input / output interface for transmitting / receiving data to / from an external device connected to the printer 1, and the like. The controller 1p receives image data relating to an image recorded on the paper P from an external device such as a PC (Personal Computer) via an interface, and stores the image data in the RAM. Then, the controller 1p controls conveyance of the paper P and recording on the paper P based on the image data stored in the RAM.

  When receiving the recording command, the controller 1p activates the entire conveyance path. Specifically, the controller 1p first drives the transport motor 21M to rotate the belt roller 6 and waits until the traveling speed of the transport belt 8 is stabilized at a predetermined speed. During the standby, the controller 1p converts the image data included in the print command into print data corresponding to the arrangement mode of the discharge ports 14a, and stores it in a predetermined area of the RAM. After the traveling speed of the transport belt 8 is stabilized at a predetermined speed, the controller 1p drives the paper feed motor 25M and the feed motor 26M to rotate the paper feed roller 25 and the feed roller pair 26, respectively, so that the paper P is transported by the transport unit 21. To supply sequentially. A paper sensor 32 is installed downstream of the pressing roller 4 in the paper conveyance direction. Based on the detection signal received from the paper sensor 32, the controller 1 p determines the ink ejection timing from the four heads 10. When the paper P crosses directly under the ejection surface 10x, ink is ejected in order from the large number of ejection ports 14a according to the recording data, and a desired color image is formed on the paper P. Thereafter, the paper P is sent to the paper discharge unit 31 by the feed roller pair 28.

  Here, with the passage of time, foreign matter (ink, paper powder, dust, etc.) adheres to the ejection surface 10x, and the viscosity of the ink increases at the ejection port 14a where the number of ejections is small. Since any phenomenon causes the ink ejection performance to deteriorate, the controller 1p performs a process for recovering the ejection performance every predetermined time or every predetermined number of recording sheets. Such processing includes flushing and purging. Flushing is a process of ejecting ink from the ejection port 14a by driving the actuator unit 17 based on flushing data different from image data. Purge refers to a process for forcibly discharging ink from the discharge port 14a by driving the pump.

  Next, the configuration of the head 10 will be described in more detail with reference to FIGS.

  The reservoir unit 11 is a flow path member in which a plurality of metal plates (not shown) are laminated and bonded together. Inside the reservoir unit 11, an ink flow path for temporarily storing ink supplied from the cartridge 39 (see FIG. 1) is formed. One end of the ink flow path is connected to the cartridge 39 via a tube or the like, and the other end is connected to an opening on the lower surface of the reservoir unit 11.

  The flow path unit 12 is a flow path member in which nine rectangular metal plates 12a, 12b, 12c, 12d, 12e, 12f, 12g, 12h, and 12i (see FIG. 4) having substantially the same size are stacked and bonded together. is there. As shown in FIG. 2, an opening 12 y that faces an opening (not shown) on the lower surface of the reservoir unit 11 is formed in the upper surface 12 x of the flow path unit 12. As shown in FIGS. 2 to 4, the ink flow path inside the flow path unit 12 includes a manifold flow path 13 having an opening 12 y at one end, a sub-manifold flow path 13 a branched from the manifold flow path 13, and a sub-manifold flow. An individual ink flow path 14 extending from the outlet of the path 13a to the discharge port 14a via the pressure chamber 16 is included.

  In FIG. 3, the pressure chamber 16 and the aperture 15 which are located below the actuator unit 17 and should be indicated by dotted lines are indicated by solid lines.

  As shown in FIG. 2, the actuator units 17 each have a trapezoidal planar shape, and are arranged in two rows in a staggered pattern on the upper surface 12 x of the flow path unit 12. Further, as shown in FIG. 3, in the trapezoidal region where the actuator units 17 of the flow path unit 12 face each other, the upper surface 12x of the flow path unit 12 is provided with a number of substantially rhomboid openings through which the pressure chambers 16 are exposed. In addition, the same number of discharge ports 14 a as the pressure chambers 16 are opened on the lower surface (discharge surface 10 x) of the flow path unit 12. The discharge surface 10x includes a discharge region 10a in which the discharge port 14a is opened and a non-discharge region 10b in which the discharge port 14a is not open. The discharge area 10 a is substantially equal to the area facing the actuator unit 17. The non-ejection area 10b is an area of the ejection surface 10x excluding the ejection area 10a.

  The reservoir unit 11 is adhered to a portion of the upper surface 12x of the flow path unit 12 where the actuator unit 17 is not disposed (a region surrounded by a two-dot chain line including the opening 12y illustrated in FIG. 2). That is, the lower surface of the reservoir unit 11 has irregularities, and the tip surface of the convex portion is bonded to the upper surface 12 x of the flow path unit 12. Thereby, the opening on the lower surface of the reservoir unit 11 communicates with the opening 12y.

  The FPC 50 is a flat flexible board on which a driver IC (not shown) is mounted in the middle thereof, and is provided for each actuator unit 17. The FPC 50 has one end fixed to the actuator unit 17 and the other end fixed to the circuit board of the head 10. Under the control of the controller 1p, the FPC 50 transmits a signal adjusted by the circuit board based on the image data to the driver IC, and transmits a drive signal generated in the driver IC to the actuator unit 17.

  Next, the wiper unit 40 will be described with reference to FIGS.

  As shown in FIG. 5, the wiper unit 40 is provided for each of the four heads 10. The four wiper units 40 are arranged side by side in the sub-scanning direction at the same interval as the arrangement pitch of the heads 10 on the side of the transport unit 21 in the space A in the housing 1a shown in FIG.

  The wiper unit 40 includes a first wiper 41, a second wiper 42, a support member 43 that supports the wipers 41, 42, a belt 44, a pair of pulleys 45a and 45b around which the belt 44 is wound, a pair of guide plates 47, and A wiper moving motor 40M (see FIG. 10) is included. The wiper units 40 move the wipers 41 and 42 relative to the ejection surface 10x while contacting the ejection surface 10x so as to remove foreign matters on the ejection surface 10x of the corresponding head 10, respectively. Such foreign matter removal processing on the ejection surface 10x by the wipers 41 and 42 is referred to as wiping. The wiping is executed after flushing or purging under the control of the controller 1p. Details of wiping will be described later.

  The support member 43 is made of resin or the like, and includes a support plate 43a shown in FIG. 7A and a clamping plate 43b shown in FIG. 7D. The support plate 43a includes a flat surface 43a1 that faces the wipers 41 and 42, and two convex portions 43p that protrude from the flat surface 43a1. The plane 43a1 has a rectangular shape that is long in the sub-scanning direction, and is inclined by a predetermined angle (acute angle) with respect to the vertical direction (see FIGS. 8A and 8B). The protrusion 43p protrudes in a direction orthogonal to the plane 43a1. The sandwiching plate 43b is a flat plate member that sandwiches the wipers 41 and 42 together with the support plate 43a. Two holes 43bp through which each of the convex portions 43p are inserted are formed in the holding plate 43b (see FIG. 8A). Both the support plate 43a and the clamping plate 43b support the lower end portions of the wipers 41 and 42.

  The 2nd wiper 42 consists of elastic materials, such as rubber | gum, and is a substantially rectangular plate-shaped member (refer FIG.7 (b)). The second wiper 42 has a concave shape in which a tip portion is notched in a concave shape and has a pair of second contact portions 42a at the tip. Each second contact portion 42a is a portion that contacts the ejection surface 10x, and extends linearly in the sub-scanning direction.

  The first wiper 41 is made of an elastic material such as rubber, like the second wiper 42, and is a substantially rectangular plate-like member (see FIG. 7C). The first wiper 41 is disposed on the downstream side of the second wiper 42 with respect to the movement direction of the wipers 41 and 42 (a direction parallel to the main scanning direction; hereinafter simply referred to as “movement direction”). The tip of the first wiper 41 is a first contact portion 41a that contacts the ejection surface 10x, and extends linearly in the sub-scanning direction and is tapered.

  The second contact portion 42a is provided as a pair on both sides in the sub-scanning direction with respect to the first contact portion 41a. The first contact portion 41a and the pair of second contact portions 42a are arranged symmetrically with respect to the center of the ejection surface 10x with respect to the sub-scanning direction. The pair of second contact portions 42a each have a portion overlapping with the first contact portion 41a in the sub-scanning direction. The total length of the contact portions 41a and 42a of the wipers 41 and 42 in the sub scanning direction is longer than the length of the ejection surface 10x in the sub scanning direction. When the contact portions 41a and 42a contact the ejection surface 10x, the pair of second contact portions 42a extend to the outside of the ejection surface 10x in the sub-scanning direction. The first abutting portion 41a abuts at least a portion including the ejection region 10a in the ejection surface 10x, and abuts against a part of the ejection region 10a and the non-ejection region 10b in the present embodiment. The second contact portion 42a contacts at least a portion of the non-discharge region 10b where the first contact portion 41a does not contact and does not contact the discharge region 10a. FIG. 3 shows a region 41ar where the first contact portion 41a contacts the discharge surface 10x and a region 42ar where the second contact portion 42a contacts the discharge surface 10x. The region 41ar overlaps with the discharge regions 10a arranged in a staggered manner in the main scanning direction in the sub-scanning direction and extends outside the discharge region 10a.

  Here, when wiping with a single wiper, the width of the wiper is made larger than the width of the ejection surface 10x from the viewpoint of preventing foreign matter from remaining. However, depending on the amount, foreign matter partially spreads outward in the width direction of the wiper before moving downward through the wiper. At this time, if a hydrophilic member is provided adjacent to the periphery of the ejection surface 10x, a part of the foreign matter may remain on the member. Residual foreign matter may return to the inner side in the width direction of the wiper after wiping and spread or drop again on the ejection surface 10x, thereby causing contamination in the printer 1.

  In contrast, in the present embodiment, the width of the first wiper 41 is smaller than the width of the ejection surface 10x. Furthermore, the region 41ar (a part of the ejection region 10a and the non-ejection region 10b) with which the first wiper 41 abuts is also a region where the water repellent film is formed. Therefore, at the time of wiping, foreign matter moves preferentially to the first wiper 41 that is more hydrophilic than the water repellent film. Thereby, the movement of the foreign matter as described above to the outside in the wiper width direction is suppressed. Further, in this state, wiping by the second wiper 42 is performed via a predetermined time difference. At this time, the foreign matter remaining on the ejection surface 10x after wiping by the first wiper 41 moves to the inside in the wiper width direction and is removed in a state where the spread to the outside in the wiper width direction is restricted. As a result, unnecessary spread of residual foreign matter on the ejection surface 10x can be suppressed, and foreign matter on the ejection surface 10x can be reliably removed.

  The height of the second wiper 42 (the length in the height direction shown in FIGS. 7 and 8) is larger than the height of the first wiper 41, and the second contact portion 42a is more than the first contact portion 41a. Located above. The height direction is a direction from the lower end to the tip of each wiper 41, 42, and in this embodiment, it is inclined by a predetermined angle with respect to the vertical direction. This is because the flat surface 43a1 of the support plate 43a is inclined, and the wipers 41 and 42 and the sandwiching plate 43b are both supported on the flat surface 43a1 while being inclined at a predetermined angle with respect to the vertical direction. That is, the height direction is the same as the extending direction of the flat surface 43a1 viewed from the sub-scanning direction.

  As shown in FIG. 7C, the first wiper 41 has four recesses 41q and four protrusions 41r protruding from the bottoms of the recesses 41q on the surface on the downstream side in the movement direction. The recess 41q is circular when viewed from a direction orthogonal to the surface of the first wiper 41. The protrusion 41r defines a cylindrical hollow portion and is provided with a pair of slits 41rs that allow the hollow portion to communicate with the outside. The pair of slits 41rs are formed to face each other in the vertical direction across the axis in the protruding direction of the protrusion 41r. The first wiper 41 also has two holes 41p. The recess 41q, the protrusion 41r, and the hole 41p are arranged in a line in the sub-scanning direction at the lower end portion of the first wiper 41. Two sets of recesses 41q and projections 41r are arranged inside the hole 41p, and one set of recesses 41q and projections 41r are arranged outside the hole 41p.

  As shown in FIGS. 7B and 7C, the second wiper 42 is formed to face each of the four through holes 42q formed to face each of the protrusions 41r in the moving direction and each of the holes 41p. Two holes 42p. The through hole 42q has a circular shape that is slightly smaller than the concave portion 41q when viewed from the direction orthogonal to the surface of the second wiper 42, and is substantially the same size as the hollow portion defined by the protrusion 41r. The through hole 42q is formed so that the center position thereof coincides with the corresponding recess 41q and protrusion 41r. Each of the holes 41p and 42p is a portion through which the convex portion 43p of the support member 43 is inserted, and has a size slightly larger than the convex portion 43p (see FIG. 8A).

  A thin plate 49 is disposed on the surface of the second wiper 42 on the downstream side in the moving direction. The thin plate 49 has a thickness smaller than that of the wipers 41 and 42, and has substantially the same plane size as the sandwiching plate 43b. The thin plate 49 is disposed at the lower end portion of the second wiper 42. The thin plate 49 is also formed with holes similar to the holes 42p and 42q. The thin plate 49 is sandwiched between the wipers 41 and 42. The free lengths 41L and 42L of the wipers 41 and 42 are lengths obtained by subtracting the height of the thin plate 49 from the height of the wipers 41 and 42 (see FIG. 8A). Further, the rigidity of the thin plate 49 is larger than the rigidity of the wipers 41 and 42. Therefore, the free length of the wipers 41 and 42 is shortened by the height of the thin plate 49. The free length 41L of the first wiper 41 is shorter than the free length 42L of the second wiper 42.

  In the assembling step of the wipers 41 and 42, first, as shown in FIGS. 7A and 7B, the convex portion 43p is inserted into the hole 42p, and the thin plate 49 is disposed on the surface on the downstream side in the moving direction. The second wiper 42 is placed on the flat surface 43a1 of the support plate 43a. Then, as shown in FIG. 7C, the convex portion 43p is inserted into the hole 41p, and the first wiper 41 is placed on the surface of the second wiper 42 on the downstream side in the moving direction. Then, as shown in FIG. 7D, the convex portion 43p is inserted into the hole 43bp (see FIG. 8A), and the clamping plate 43b is placed on the downstream side in the movement direction of the first wiper 41. At this time, the clamping plate 43b is supported on the tip of the protrusion 41r. Thereafter, the portion of the convex portion 43p on the downstream side in the moving direction with respect to the clamping plate 43b is expanded by heat caulking or the like (the portion 43p1 expanded in diameter in FIGS. 7D, 8A, and 8B). It is shown). Accordingly, the wipers 41 and 42 are sandwiched between the support plate 43 a and the sandwich plate 43 b and are fixed to the support member 43.

  As shown in FIG. 8A, the convex portion 43p has a shaft portion 43px inserted through the holes 42p, 41p, and 43bp, and has a diameter larger than that of the shaft portion 43px on the downstream side in the movement direction from the sandwiching plate 43b. And a tip portion 43py for supporting the sandwiching plate 43b. In the present embodiment, the base portion of the distal end portion 43py is enlarged in diameter and is in contact with the surface on the downstream side in the movement direction of the sandwiching plate 43b. Further, the clamping plate 43b supported by the tip portion 43py presses the tip of the protrusion 41r toward the support plate 43a (see FIG. 8B). The sandwiching plate 43b is not in contact with a portion other than the protrusion 41r of the first wiper 41. That is, a gap is formed between the clamping plate 43b and the surface of the first wiper 41 on the downstream side in the movement direction. Although not shown in FIG. 8B, the protrusion 41r is deformed by the pressing force from the clamping plate 43b. A part of the deformed first wiper 41 in the vicinity of the protrusion 41r enters the through hole 42q.

  The support member 43 also has a pair of U-shaped members 43u on both sides of the support plate 43a in the sub-scanning direction. Each of the pair of U-shaped members 43u has one side wall fixed to the end surface in the sub-scanning direction of the support plate 43a and the other side wall spaced from the support plate 43a. The support plate 43a is sandwiched from both sides in the sub-scanning direction by one side wall of the pair of U-shaped members 43u. On the other side wall of the pair of U-shaped members 43u, convex portions 43t are provided that protrude in the sub-scanning direction and outward (in the direction away from the support plate 43a). The convex portion 43 t is a portion that is inserted into the guide hole 47 a of the guide plate 47. Further, the bottom surface 43 c (see FIGS. 8A and 8B) of the support member 43 is fixed to the outer peripheral surface of the upper loop of the belt 44. That is, the support member 43 is supported by both the belt 44 and the guide plate 47 and can move in the main scanning direction as the belt 44 travels.

  Each guide plate 47 is a flat plate-like member that is long in the main scanning direction, and is erected in the vertical direction. The pair of guide plates 47 is disposed above the belt 44 and the pulleys 45a and 45b at a position sandwiching the ejection surface 10x in the sub-scanning direction. The pair of guide plates 47 are connected to each other by stoppers 47s provided at both ends in the main scanning direction. The stopper 47s prevents the support member 43 from falling. Each guide plate 47 is formed with a guide hole 47a. The guide hole 47a extends in the main scanning direction and is longer than the length of the ejection surface 10x in the main scanning direction.

  As shown in FIG. 6, the pulleys 45a and 45b are spaced apart from each other with an interval longer than the length of the ejection surface 10x in the main scanning direction. The pulley 45b is a driving pulley, and is driven by a wiper movement motor 40M (see FIG. 10) connected to the shaft under the control of the controller 1p (at the time of wiping, counterclockwise as shown in FIG. 9A). To) rotate. When the pulley 45b rotates, the belt 44 travels. The pulley 45 a is a driven pulley and rotates as the belt 44 travels.

  Next, the operation of the wiper unit 40 related to wiping will be described. The wiping may be performed independently for each head 10 or may be performed in synchronization with the four heads 10.

  During standby, the support member 43 is disposed at a position in contact with the right stopper 47s of FIG. When wiping is performed, first, driving of each part is stopped in the entire transport path. Next, under the control of the controller 1p, the head 10 moves in the main scanning direction as indicated by the thick arrow in FIG. 5 by driving the head moving motor 10M (see FIG. 10), and the recording position (solid line in FIG. 5). The position is moved from the position facing the conveying belt 8 in the vertical direction to the wiping position (the position shown by the dotted line in FIG. 5; the position facing the belt 44 in the vertical direction). At this time, the discharge surface 10x is located below the contact portions 41a and 42a.

  When the head 10 stops at the wiping position, the pulley 45b rotates and the belt 44 travels under the control of the controller 1p. Thereby, the support member 43 moves in the moving direction while supporting the wipers 41 and 42. At this time, the contact portions 41a and 42a move relative to the discharge surface 10x while sequentially contacting the regions 41ar and 42ar (see FIG. 3), respectively, thereby removing foreign matters on the discharge surface 10x. . At this time, a gap is formed between the first contact portion 41a and the second contact portion 42a with respect to the moving direction (see FIG. 9B). As a result, the foreign matter on the ejection surface 10x is held in the gap formed between the first contact portion 41a and the second contact portion 42a, and further down through the first wiper 41 and the second wiper 42. Move to. At this time, the angle θ1 on the downstream side in the movement direction made by the first contact portion 41a with respect to the ejection surface 10x is smaller than the angle θ2 on the downstream side in the movement direction made by the second contact portion 42a with respect to the ejection surface 10x. large. Furthermore, the contact portions 41a and 42a overlap the discharge surface 10x by a predetermined amount in the vertical direction. The amount that the first contact portion 41a overlaps with the discharge surface 10x in the vertical direction is smaller than the amount that the second contact portion 42a overlaps with the discharge surface 10x in the vertical direction.

  Thereafter, when the support member 43 reaches a position where it comes into contact with the left stopper 47s of FIG. 9A, the rotation of the pulley 45b is stopped. Thereby, wiping of the entire discharge surface 10x is completed. After completion of wiping, under the control of the controller 1p, the head moving motor 10M (see FIG. 10) is driven to move the head 10 upward so that the ejection surface 10x reaches above the contact portions 41a and 42a. Stop. Thereafter, under the control of the controller 1p, the pulley 45b rotates in the opposite direction to that during wiping, and the belt 44 travels in the opposite direction from that during wiping. Then, when the support member 43 reaches a position where it comes into contact with the right stopper 47s of FIG. 9A, the rotation of the pulley 45b is stopped.

  Thereafter, under the control of the controller 1p, the head 10 moves in the main scanning direction by the driving of the head moving motor 10M (see FIG. 10), and moves from the wiping position to the recording position. At this time, the contact portions 41a and 42a are located below the discharge surface 10x, and therefore do not come into contact with the discharge surface 10x.

  As described above, according to the present embodiment, at least foreign matter on the discharge region 10a is removed by the first wiper 41, and then foreign matter that could not be removed by the first wiper 41 is removed by the second wiper 42. Is done. Further, since the second wiper does not come into contact with the discharge region 10a, damage to the discharge region 10a can be suppressed. That is, according to the present embodiment, it is possible to reliably remove the foreign matter on the ejection surface 10x while suppressing damage to the ejection region 10a.

  When the wipers 41 and 42 are moved relative to the ejection surface 10x, a gap is formed between the first contact portion 41a and the second contact portion 42a in the moving direction (FIG. 9 ( b)). As a result, the foreign matter on the ejection surface 10x is held in the gap formed between the first contact portion 41a and the second contact portion 42a, and further down through the first wiper 41 and the second wiper 42. Move to. Therefore, the foreign matter on the ejection surface 10x can be more reliably removed than when there is no gap.

  The amount of overlap with the discharge surface 10x in the vertical direction when the first contact portion 41a contacts the discharge surface 10x overlaps with the discharge surface 10x in the vertical direction when the second contact portion 42a contacts with the discharge surface 10x. Less than the amount you want. Thereby, especially in the configuration in which the wipers 41 and 42 are integrally supported by the support member 43 as in the present embodiment, a gap is formed between the first contact portion 41a and the second contact portion 42a in the movement direction. It can be formed easily.

  The angle θ1 on the downstream side in the moving direction with respect to the ejection surface 10x when the first abutment portion 41a abuts on the ejection surface 10x is equal to the discharge surface 10x when the second abutment portion 42a abuts on the ejection surface 10x. It is larger than the angle θ2 on the downstream side in the moving direction (see FIG. 9B). Thereby, especially in the configuration in which the wipers 41 and 42 are integrally supported by the support member 43 as in the present embodiment, a gap is formed between the first contact portion 41a and the second contact portion 42a in the movement direction. It can be formed easily. Further, since the angle θ1 of the first contact portion 41a is relatively large, the frictional force with respect to the discharge surface 10x of the first contact portion 41a is relatively large, and the first contact portion 41a causes the foreign matter on the discharge region 10a. Can be removed more reliably.

  The free length 41L of the first wiper 41 is shorter than the free length 42L of the second wiper 42 (see FIG. 8A). Thereby, the relationship between the overlapping amounts and / or the angles in the first contact portion 41a and the second contact portion 42a can be easily formed.

  The wiper unit 40 includes one support member 43 that supports the wipers 41 and 42. Thereby, the whole wiper unit 40 can be reduced in size. If the wipers 41 and 42 are respectively supported at positions separated from each other by individual support members, the entire wiper unit 40 can be enlarged.

  The first wiper 41 has a protrusion 41r, and the sandwiching plate 43b supported by the tip portion 43py presses the tip of the protrusion 41r toward the support plate 43a (see FIG. 8B). That is, the wipers 41 and 42 are fixed by the pressing force applied from the clamping plate 43b to the protrusion 41r. If the first wiper 41 does not have the protrusion 41r, and the flat first wiper 41 and the second wiper 42 are sandwiched and fixed by the flat support plate 43a and the sandwich plate 43b, Due to the variation in the clamping force, the tip of the wipers 41 and 42 may be deformed such as a wave. Deformation of the tips of the wipers 41 and 42 can be caused by unevenly escaping the meat of the sandwiched portions of the wipers 41 and 42 by the clamping force. According to the present embodiment, by applying the pressing force to the protrusions 41r in a concentrated manner, uneven meat escape can be suppressed, and variation in clamping force is unlikely to occur. For this reason, the tip of the wipers 41 and 42 is hardly deformed.

  Moreover, the second wiper 42 has a through hole 42q formed to face the protrusion 41r in the moving direction. Therefore, the portion near the projection 41r of the first wiper 41 is deformed by the pressing force from the clamping plate 43b, and the deformed portion enters the through hole 42q. Thereby, the uneven escape of meat is more reliably suppressed, and the first wiper 41 and the second wiper 42 are fixed to each other.

  Further, since the protrusion 41r protrudes from the bottom surface of the recess 41q and the protrusion 41r has a pair of slits 41rs, the amount of escape upward of the meat is reduced, and the tips of the wipers 41 and 42 are deformed. Is more reliably suppressed.

  The second contact portion 42a is provided as a pair on both sides in the sub-scanning direction with respect to the first contact portion 41a. The first contact portion 41a and the pair of second contact portions 42a are arranged symmetrically with respect to the center of the ejection surface 10x with respect to the sub-scanning direction. Thereby, the whole discharge surface 10x can be wiped uniformly.

  Each of the pair of second contact portions 42a extends to the outside of the discharge surface 10x in the sub-scanning direction when contacting the discharge surface 10x. Thereby, it can suppress that a foreign material remains in the edge part of the subscanning direction of the discharge surface 10x. Therefore, it is possible to more reliably realize wiping the entire discharge surface 10x evenly.

  Each of the pair of second contact portions 42a has a portion overlapping with the first contact portion 41a in the sub-scanning direction. Thereby, the foreign matter that could not be removed by the first wiper 41 can be more reliably removed by the second wiper 42.

  The 2nd wiper 42 is a concave shape which has a pair of 2nd contact parts 42a at the tip, respectively. Thereby, compared with the case where a pair of 2nd contact parts 42a are each comprised by a separate member, a number of parts can be reduced.

  A thin plate 49 is sandwiched between the wipers 41 and 42 (see FIGS. 8A and 8B). With respect to the vertical direction, the length of the thin plate 49 is shorter than any of the lengths of the wipers 41 and 42. Thereby, especially in the configuration in which the wipers 41 and 42 are integrally supported by the support member 43 as in the present embodiment, a gap is formed between the first contact portion 41a and the second contact portion 42a in the movement direction. It can be formed easily. Further, by setting the length of the thin plate 49 as described above, the free lengths 41L and 42L of the wipers 41 and 42 can be shortened by the length of the thin plate 49 having high rigidity. Thereby, the frictional force with respect to the discharge surface 10x of each contact part 41a, 42a becomes comparatively large, and the foreign matter on the discharge surface 10x can be more reliably removed by each contact part 41a, 42a.

  A hydrophilic member is provided around the discharge surface 10x. In this case, after wiping is completed, there may be a phenomenon that the foreign matter once moved around the discharge surface 10x by wiping returns to the discharge surface 10x again. However, according to the present embodiment, the above phenomenon can be suppressed by effective wiping using the wipers 41 and 42.

  The discharge surface 10x is long in the movement direction, and the contact portions 41a and 42a extend in a direction parallel to the discharge surface 10x and orthogonal to the movement direction. Thereby, even when the discharge surface 10x is long in the moving direction, the wiper unit 40 can be downsized.

  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.

The number of liquid ejection heads may be an arbitrary number of 1 or more.
The liquid discharge head may discharge any liquid other than ink (for example, a processing liquid having a function of preventing ink bleeding or back-through).
The recording medium is not limited to the paper P, and may be any recordable medium.
The liquid discharge head is not limited to the line type, and may be a serial type. In this case, the wiper unit may be fixed at a position adjacent to the print area, for example. Then, the wiping may be performed by moving the head with respect to the fixed wiper unit.
The liquid ejection device is not limited to a printer, and may be a facsimile, a copier, or the like.
The movement direction of the first wiper and the second wiper with respect to the ejection surface is not particularly limited, and may be, for example, the sub-scanning direction instead of the main scanning direction.
-A hydrophilic member may not be provided around the discharge surface.
-You may abbreviate | omit a clamping member.
The first wiper and the second wiper may be supported by individual support members at positions separated from each other (for example, positions separated from each other in the main scanning direction in the above-described embodiment).
The first wiper and the second wiper are not limited to being made of an elastic material such as rubber, and may be made of any material. For example, only the contact portion may be made of an elastic material, and the portion other than the contact portion may be made of a rigid material.
-A 2nd wiper is not limited to concave shape, You may consist of two members which respectively have a 2nd contact part in the front-end | tip.
-A 1st contact part and a pair of 2nd contact part do not need to be arrange | positioned symmetrically with respect to the center of a discharge surface regarding the direction parallel to a discharge surface and orthogonal to a moving direction.
The second contact portion is not limited to being provided as a pair on both sides in the direction parallel to the discharge surface and perpendicular to the moving direction with respect to the first contact portion, and the second contact portion described above with respect to the first contact portion It may be provided only in one of the directions.
The number, position, shape, etc. of the protrusions of the first wiper may be changed as appropriate. The slit of the protrusion may be omitted.
-You may abbreviate | omit the protrusion and / or recessed part of a 1st wiper.
-You may change suitably the support structure of the 1st wiper by a support member, and a 2nd wiper. For example, in the above-described embodiment, the first wiper 41 and the second wiper 42 are sandwiched between the support plate 43a and the sandwiching plate 43b. However, the sandwiching plate 43b is omitted, and the wiper 41 is expanded by expanding the tip of the convex portion 43p. , 42 may be supported by the support plate 43a while preventing the detachment of the wipers 41, 42.
The free length of the first wiper and the second wiper can be arbitrarily set, and the free length of the first wiper may be the same as or longer than the free length of the second wiper.
The angle on the downstream side in the movement direction with respect to the discharge surface when contacting the discharge surface of the first contact portion and the second contact portion is arbitrary, and the angle of the first contact portion is the second contact angle. It may be equal to or smaller than the angle of the contact portion.
The amount of overlap with the discharge surface in the direction orthogonal to the discharge surface when contacting the discharge surface of the first contact portion and the second contact portion is arbitrary, and the amount of the first contact portion is the second It may be equal to or greater than the amount of the contact portion.
-The part of the ejection surface with which the first abutting part abuts may be only the ejection area, or may be a part of the ejection area and the non-ejection area.
The arrangement of the ejection area and the non-ejection area on the ejection surface is arbitrary, and in the above-described embodiment, the ejection areas are arranged in a staggered pattern in the main scanning direction, but the ejection areas are arranged in a straight line in the main scanning direction. May be.

1 Inkjet printer (liquid ejection device)
1p controller (moving means)
10 Inkjet head (liquid discharge head)
10a discharge area 10b non-discharge area 10x discharge surface 14a discharge port 40 wiper unit 40M wiper moving motor (moving means)
41 1st wiper 41a 1st contact part 41q recessed part 41r protrusion 41rs slit 42 2nd wiper 42a 2nd contact part 42q through-hole 43 support member 43a support plate 43a1 plane 43b clamping plate 43p convex part 43px shaft part 43py tip part 49 Thin plate (clamping member)

Claims (19)

A liquid discharge head having a discharge surface including a discharge region in which a plurality of discharge ports for discharging liquid are open and a non-discharge region in which the discharge port is not open;
A wiper unit including a first wiper and a second wiper for removing foreign matter on the discharge surface by moving relative to the discharge surface while being in contact with the discharge surface;
Moving means for moving the first wiper and the second wiper relative to the discharge surface;
The first wiper is disposed downstream of the second wiper with respect to the moving direction of the moving means, and has a first abutting portion that abuts at least the entire area of the ejection region of the ejection surface,
The second wiper is a second abutting portion that abuts at least a portion of the non-ejection region where the first abutting portion does not abut and does not abut on the ejection region, and is parallel to the ejection surface. The liquid ejecting apparatus further includes a second contact portion that overlaps the first contact portion in a direction orthogonal to the moving direction .   When the moving means moves the first wiper and the second wiper relative to the discharge surface, the movement direction is between the first contact portion and the second contact portion. The liquid ejection device according to claim 1, wherein a gap is formed in the liquid ejection device.   The amount of overlap with the discharge surface in the direction orthogonal to the discharge surface when the first contact portion contacts the discharge surface is the discharge surface when the second contact portion contacts the discharge surface. The liquid ejecting apparatus according to claim 2, wherein the liquid ejecting apparatus is smaller than an amount overlapping with the ejection surface in a direction orthogonal to the direction.   The angle on the downstream side in the movement direction with respect to the ejection surface when the first abutment portion abuts on the ejection surface is such that the second abutment portion contacts the ejection surface when the second abutment portion abuts on the ejection surface. The liquid ejection apparatus according to claim 2, wherein the liquid ejection apparatus is larger than an angle on the downstream side in the moving direction.   5. The liquid ejection apparatus according to claim 3, wherein a free length of the first wiper is shorter than a free length of the second wiper.   The liquid ejecting apparatus according to claim 1, wherein the wiper unit further includes one support member that supports the first wiper and the second wiper. The first wiper has a protrusion protruding from the surface on the downstream side in the moving direction ,
The support member, the support plate and, wherein the protrusion is pressed toward the supporting plate and the first wiper and the first wiper supporting plate having a flat surface facing the first wiper and the second wiper wherein the clamping plates sandwiching at second wiper and the support plate, characterized in that it have a liquid discharge apparatus according to claim 6 between. A hollow portion is formed in the protrusion, and a pair of slits for communicating the hollow portion and the outside are formed to face each other in a direction perpendicular to the discharge surface with an axis in the protrusion direction of the protrusion interposed therebetween. The liquid ejecting apparatus according to claim 7, wherein the liquid ejecting apparatus is a liquid ejecting apparatus.   The surface of the first wiper has a recess and the protrusion protruding from the bottom of the recess,
  The liquid ejecting apparatus according to claim 8, wherein the second wiper has a through hole formed to face the protrusion with respect to the moving direction.   The concave portion is formed corresponding to the through hole of the second wiper, and is circular when viewed from a direction orthogonal to the surface,
  The liquid ejection device according to claim 9, wherein the hollow portion is cylindrical.   The support member further includes a protrusion protruding from the plane,
  The convex portion includes a shaft portion that is inserted through a hole formed in each of the first wiper, the second wiper, and the clamping plate, and the shaft portion on the downstream side in the movement direction from the clamping plate. A tip portion that also expands the diameter and supports the sandwich plate,
  The liquid ejecting apparatus according to claim 7, wherein the sandwiching plate supported by the tip portion presses the protrusion toward the support plate. The second contact portion is provided as a pair with respect to the first contact portion on both sides in a direction parallel to the discharge surface and perpendicular to the moving direction.
The first contact portion and the pair of second contact portions are arranged symmetrically with respect to the center of the discharge surface with respect to a direction parallel to the discharge surface and perpendicular to the moving direction. to, a liquid ejecting apparatus according to any one of claims 1 to 11. Each of the pair of second contact portions extends to the outside of the discharge surface with respect to a direction parallel to the discharge surface and perpendicular to the moving direction when contacting the discharge surface. The liquid ejection device according to claim 12 . Second contact portions of the pair, respectively, with respect to the direction orthogonal to the parallel and the moving direction and the ejection surface, characterized by having a portion which overlaps with the first contact portion, claim 12 or liquid ejecting apparatus according to 1 3. The second wiper is characterized in that the pair of the second contact portion are each concave shape having a tip, a liquid ejecting apparatus according to any one of claims 12 to 1 4. A gripping member sandwiched between the first wiper and the second wiper;
With respect to the direction orthogonal to the ejection surface, and wherein the length of the clamping member is shorter than both the length and the length of the second wiper of the first wiper, any claim 1 to 1 5 The liquid ejection device according to claim 1.   The liquid ejecting apparatus according to claim 16, wherein a rigidity of the clamping member is larger than a rigidity of the first wiper and a rigidity of the second wiper. Wherein the hydrophilic member around the discharge surface is provided, the liquid ejecting apparatus according to any one of claims 1 to 1 7. The longitudinal direction of the ejection surface is a direction along the movement direction;
Said first contact portion and the second contact portion, characterized in that it extends in a direction orthogonal to the moving direction parallel to the discharge surface, claim 1-1 8 The liquid ejection device according to one item.

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