JP2010149370A - Suction cap apparatus, cap chip, and liquid delivering apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a suction cap apparatus capable of protecting a liquid delivering face, a cap chip, and a liquid transferring apparatus. <P>SOLUTION: The suction cap apparatus 13 provided on a printer includes: a cap 60 capable of covering an ink delivering face 38; the cap chips 67 and 68 arranged in the cap 60; and a suction pump 14. The cap 60 has a bottom wall 69, a sidewall 70 standing from the bottom wall 69, and a lip 76 projecting from the sidewall 70. When the lip 76 comes into close contact with the ink delivering face 38 and performs capping, projections 74 and 75 stand at positions which do not oppose the nozzle formed on the ink delivering face 38 of the cap chips 67 and 68 and its vicinities. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a suction cap device, a cap chip, and a liquid ejection device.

  In general, a liquid discharge apparatus having a liquid discharge head for discharging liquid can cover a liquid discharge surface on which a nozzle of the liquid discharge head is formed, and an annular lip protruding from the bottom wall. A cap member is provided. The cap member is connected to a suction means such as a suction pump, and covers the liquid discharge surface of the liquid discharge head from the inside of the nozzle by the suction pump when sucking the liquid from the nozzle in order to prevent defective discharge of the nozzle. Accepts sucked bubbles and thickened liquid.

  By the way, when the suction operation by the suction pump is performed by covering the liquid discharge surface with the cap member, the internal space of the cap member is depressurized. At this time, the lip falls to the sealed space side due to the pressure difference from the outside of the internal space. As a result, a gap may be formed between the cap member and the liquid discharge surface. Accordingly, a cap chip that is housed in a cap member and prevents the lip from falling down is conventionally known. However, even if the tip of the lip is prevented by the cap chip, the bottom wall having the largest surface area of the cap member is deformed to the liquid discharge surface side due to the pressure difference between the internal space of the cap member and the outside of the internal space. Along with the deformation of the bottom wall, the cap chip is pushed up toward the liquid discharge surface of the liquid discharge head and comes into contact with the liquid discharge surface, thereby obstructing the discharge of the liquid from the nozzle. Further, the nozzle and the vicinity thereof are damaged, and the discharge direction of the liquid from the nozzle is shifted or discharge failure occurs.

  Therefore, for example, in the ink jet recording apparatus described in Patent Document 1, the lip formed on the cap member has a protruding portion protruding toward the internal space, and the protruding portion is accommodated in the cap. The cap chip is prevented from being pushed up toward the liquid discharge surface in contact with the edge of the upper surface of the (support member).

Japanese Patent Laying-Open No. 2007-90807 (FIG. 8)

  However, as in the cap provided in the ink jet recording apparatus described in Patent Document 1, the internal space of the cap is decompressed only by regulating the pushing force toward the liquid discharge surface by contacting the edge of the cap chip. When the pressure difference outside the internal space increases, the bottom wall of the cap deforms to the liquid discharge surface side, and with this deformation, the lip opens outward and the area in contact with the cap chip decreases. The restriction of the cap chip due to the protrusion formed on the lip is released. When the bottom wall of the cap is further deformed toward the liquid discharge surface, the cap chip is released from the restriction, so that the cap chip is pushed up toward the liquid discharge surface by the bottom wall and comes into contact with the liquid discharge surface. As a result, the above-described problem occurs.

  Therefore, an object of the present invention is to provide a suction cap device, a cap chip, and a liquid transfer device that can protect a liquid discharge surface.

  The suction cap device according to the present invention includes a bottom wall portion facing a liquid discharge surface of a liquid discharge head, and an annular lip that can be brought into close contact with the liquid discharge surface that protrudes from the bottom wall portion toward the liquid discharge surface. And a cap chip that communicates with the internal space of the cap member and sucks the internal space; and a cap chip disposed in the internal space of the cap member, and the lip When capping is in close contact with the liquid discharge surface, a protrusion stands at a position on one surface opposite to the bottom wall portion of the cap chip that does not face the discharge port formed on the liquid discharge surface. It is installed.

  In order to suck liquid from the discharge port, the cap member lip is brought into close contact with the liquid discharge surface, and when the internal space of the cap member is depressurized by the suction operation by the suction means, the air pressure in the internal space is higher than the air pressure outside the cap member. Also lower. Then, the bottom wall portion having the largest surface area among the cap members is deformed toward the liquid ejection surface, and the cap chip is pushed up toward the liquid ejection surface along with the deformation of the bottom wall portion. According to the suction cap device of the present invention, even when the cap chip is pushed up toward the liquid discharge surface, the protrusion contacts the position not facing the discharge port of the liquid discharge surface, and the cap chip does not contact the discharge port. Therefore, the liquid discharge surface, particularly the discharge port can be protected.

  The bottom wall portion and the lip constituting the cap member are made of an elastic member and integrally molded. When the bottom wall portion and the lip are made of an elastic member, since the elastic member has a low elastic modulus, the bottom wall portion is easily deformed, and the necessity of the present invention is increased.

  Moreover, it is preferable that the front-end | tip part of the said protrusion is roundish. According to this, even if the tip of the protrusion comes into contact with the liquid discharge surface, the liquid discharge surface is hardly damaged.

  Furthermore, it is preferable that the elastic modulus of the tip portion of the protrusion is smaller than the elastic modulus of the portion excluding the tip portion. According to this, even if the tip of the protrusion comes into contact with the liquid discharge surface, the liquid discharge surface is less likely to be damaged.

  In addition, a moving mechanism that moves the cap member between a capping position where the lip is in close contact with the liquid ejection surface and a suction operation is performed by the suction means and a retracted position retracted from the capping position. It is preferable that when the cap member is moved to the capping position by the moving mechanism, the tip end portion of the protrusion abuts at a position not facing the discharge port of the liquid discharge surface. According to this, when the cap member is moved to the capping position, the tip end portion of the protrusion comes into contact with the liquid discharge surface at the same time. Is not deformed to the liquid ejection surface side, suction loss is eliminated, and liquid ejection from the ejection port can be started quickly.

  Moreover, it is preferable that the said protrusion is formed in the edge part in the said one surface of the said cap chip. According to this, when the internal space of the cap member is depressurized by the suction operation by the suction means in a state where the lip is in close contact with the liquid discharge surface, the air pressure in the internal space becomes lower than the air pressure outside the cap member, The protrusions can prevent the inner space from being bent.

  The projections may have a rod shape and a plurality of projections may be provided, and the plurality of projections may be arranged at intervals on the edge portion of the one surface of the cap chip. According to this, for example, when the liquid received on the cap chip flows from the gap between the cap member and the cap chip to the bottom wall portion, the flow of the liquid flowing from the cap chip to the gap between the cap member and the cap chip is inhibited. There is nothing.

  In addition, when viewed from a direction orthogonal to the bottom wall portion, the internal space of the cap member is partitioned into a rectangular shape by the lip, and the cap chip is disposed in the internal space in the orthogonal direction. The cap chip has a rectangular shape when viewed from the direction in which the cap chip has a side length substantially the same as a length between two opposing sides of the lip that is orthogonal to the one side of the cap chip. The length of the other side perpendicular to the one side of the tip is shorter than the length between the two sides perpendicular to the two sides of the lip, and both ends of the cap tip in the direction in which the one side extends. It is preferable that the protrusion is formed on the edge located at the position. A gap is formed between the cap chip and the cap member on both sides along the other side of the cap chip. And no protrusion is formed on the edge along one side of the cap chip. Therefore, when the liquid received on the cap chip flows through the gap between the cap member and the cap chip, flows through the bottom wall portion, and flows into the opening formed in the cap member, the cap member and the cap chip are placed on the cap chip from above. It does not hinder the flow of liquid into the gap.

  Furthermore, it is preferable that a groove extending in parallel with the other side of the cap chip is formed on the one surface of the cap chip. According to this, the liquid received on the cap chip can be quickly sent to the gap between the cap member and the cap chip.

  The cap chip according to the present invention includes a bottom wall portion facing the liquid discharge surface of the liquid discharge head, and an annular lip that can be brought into close contact with the liquid discharge surface provided to protrude from the bottom wall portion toward the liquid discharge surface. A cap chip housed in the internal space of the cap member, wherein the chip body and the lip on the side opposite to the bottom wall portion of the chip body when the lip is in close contact with the liquid ejection surface And a protrusion provided on one surface at a position not facing the discharge port formed on the liquid discharge surface.

  In order to suck liquid from the discharge port, the cap member lip is brought into close contact with the liquid discharge surface, and when the internal space of the cap member is depressurized by the suction operation by the suction means, the air pressure in the internal space is higher than the air pressure outside the cap member. Also lower. Then, the bottom wall portion having the largest surface area among the cap members is deformed toward the liquid ejection surface, and the cap chip is pushed up toward the liquid ejection surface along with the deformation of the bottom wall portion. According to the suction cap device of the present invention, even when the cap chip is pushed up toward the liquid discharge surface, the protrusion contacts the position not facing the discharge port of the liquid discharge surface, and the cap chip does not contact the discharge port. Therefore, the liquid discharge surface, particularly the discharge port can be protected.

  A liquid discharge apparatus according to the present invention includes a liquid discharge head that discharges liquid from an discharge port formed on a liquid discharge surface, and a suction cap device that can cap the liquid discharge surface of the liquid discharge head. The suction cap device has a bottom wall portion facing the liquid discharge surface of the liquid discharge head, and an annular shape that can be in close contact with the liquid discharge surface provided to protrude from the bottom wall portion toward the liquid discharge surface. A cap member having a lip, a suction means that communicates with the internal space of the cap member and sucks the internal space, and a cap tip disposed in the internal space of the cap member, The liquid discharge surface has a convex portion at a position where the discharge port is not formed.

  In order to suck liquid from the discharge port, the cap member lip is brought into close contact with the liquid discharge surface, and when the internal space of the cap member is depressurized by the suction operation by the suction means, the air pressure in the internal space is higher than the air pressure outside the cap member. Also lower. Then, the bottom wall portion having the largest surface area among the cap members is deformed toward the liquid ejection surface, and the cap chip is pushed up toward the liquid ejection surface along with the deformation of the bottom wall portion. According to the suction cap device of the present invention, even when the cap chip is pushed up toward the liquid discharge surface, the protrusion contacts the position not facing the discharge port of the liquid discharge surface, and the cap chip does not contact the discharge port. Therefore, the liquid discharge surface, particularly the discharge port can be protected.

  Even when the cap chip is pushed up toward the liquid discharge surface, the protrusion contacts the position that does not face the discharge port of the liquid discharge surface, and the cap chip does not contact the discharge port, so the liquid discharge surface is protected. Can do.

<First Embodiment>
Next, a preferred first embodiment of the present invention will be described. In the present embodiment, the present invention is applied to a suction cap device provided in a printer that records (prints) desired characters or images on a recording sheet by ejecting ink from the inkjet head onto the recording sheet. Is.

  FIG. 1 is a plan view illustrating a schematic configuration of the printer according to the first embodiment. As shown in FIG. 1, a printer 1 (liquid ejection device) includes a carriage 2 configured to be reciprocally movable along one direction, an inkjet head 3 (liquid ejection head) mounted on the carriage 2, and Sub tanks 4a to 4d, ink cartridges 6a to 6d for storing ink, and a suction cap device 13 capable of covering the ink discharge surface 38 (see FIG. 2) of the inkjet head 3 are provided.

  The carriage 2 is configured to be able to reciprocate along two guide shafts 17 extending in parallel with the scanning direction (left-right direction in FIG. 1). An endless belt 18 is connected to the carriage 2. When the endless belt 18 is driven to travel by the carriage drive motor 19, the carriage 2 moves in the scanning direction as the endless belt 18 travels. It has become.

  An ink jet head 3 and four sub tanks 4 a to 4 d are mounted on the carriage 2. The ink jet head 3 reciprocates in the scanning direction together with the carriage 2, and the paper is transported by a paper transport mechanism (not shown) from a nozzle 40 (see FIG. 2) formed on the ink ejection surface 38 (surface on the opposite side of the paper surface in FIG. 1). Ink is ejected onto the recording paper P transported in the feed direction (downward in FIG. 1). As a result, desired characters and images are recorded on the recording paper P.

  The four sub tanks 4a to 4d are arranged side by side along the scanning direction. A tube joint 20 is integrally provided in the four sub tanks 4a to 4d. The four sub tanks 4a to 4d and the four ink cartridges 6a to 6d are connected to each other through flexible tubes 5a to 5d connected to the tube joints 20, respectively. The four ink cartridges 6 a to 6 d store four colors of ink of black, yellow, cyan, and magenta, respectively, and these ink cartridges 6 a to 6 d are detachably attached to the holder 7. The four color inks stored in the four ink cartridges 6a to 6d are temporarily stored in the sub tanks 4a to 4d via the tubes 5a to 5d, and then supplied to the inkjet head 3.

  Next, the inkjet head 3 will be described. FIG. 2 is a vertical sectional view of a part of the inkjet head. As shown in FIG. 2, the inkjet head 3 flows by applying pressure to the flow path unit 22 in which the individual ink flow paths 41 including the nozzles 40 and the pressure chambers 34 are formed, and the ink in the pressure chambers 34. And a piezoelectric actuator 23 for discharging ink from the nozzles 40 of the path unit 22.

  The flow path unit 22 includes a cavity plate 30, a base plate 31, and a manifold plate 32 formed of a metal material such as stainless steel, and a nozzle formed of an insulating material (for example, a polymer synthetic resin material such as polyimide). A plate 33 is provided, and these four plates 30 to 33 are joined in a laminated state.

  A pressure chamber 34 is formed in the cavity plate 30. A plurality of pressure chambers 34 are provided side by side in the direction perpendicular to the plane of FIG. The base plate 31 has communication holes 35 and 36 that communicate with the pressure chambers 34, respectively. The manifold plate 32 is formed with a manifold 37 that communicates with the plurality of pressure chambers 34 via the communication holes 35 and a communication hole 39 that communicates with the communication holes 36. Furthermore, a plurality of nozzles 40 are formed on the nozzle plate 33, and the plurality of nozzles 40 are arranged in the direction perpendicular to the paper surface of FIG. A plurality of individual ink flow paths 41 extending from the manifold 37 to the nozzles 40 through the pressure chambers 34 are formed in the flow path unit 22.

  The piezoelectric actuator 23 includes a metal diaphragm 50 bonded to the upper surface of the flow path unit 22 so as to cover the plurality of pressure chambers 34, a piezoelectric layer 51 disposed on the upper surface of the diaphragm 50, and the piezoelectric layer 51. And a plurality of individual electrodes 52 formed on the upper surface.

  The metal diaphragm 50 is always held at the ground potential by the head driver 53. The piezoelectric layer 51 is made of a piezoelectric material mainly composed of lead zirconate titanate (PZT) which is a solid solution of lead titanate and lead zirconate and is a ferroelectric substance. It arrange | positions so that the pressure chamber 34 may be straddled. The plurality of individual electrodes 52 are respectively disposed in regions on the upper surface of the piezoelectric layer 51 facing the central portions of the plurality of pressure chambers 34. The plurality of individual electrodes 52 are supplied with either a ground potential or a predetermined drive potential different from the ground potential by the head driver 53.

  The operation of the piezoelectric actuator 23 during ink ejection will be described. When ink is ejected from a certain nozzle 40, a driving potential is applied from the head driver 53 to the individual electrode 52 corresponding to the pressure chamber 34 communicating with the nozzle 40. Then, a potential difference is generated between the individual electrode 52 to which the driving potential is applied and the diaphragm 50 held at the ground potential, and an electric field parallel to the thickness direction is generated in the piezoelectric layer 51 sandwiched between the two. Since the direction of the electric field coincides with the polarization direction of the piezoelectric layer 51, the piezoelectric layer 51 polarized in the thickness direction contracts in a plane direction orthogonal to the direction of the electric field (piezoelectric lateral effect). As a result, the portion of the diaphragm 50 facing the pressure chamber 34 is deformed so as to protrude toward the pressure chamber 34 (unimorph deformation). At this time, the volume of the pressure chamber 34 decreases, the pressure of the ink inside the pressure chamber 34 increases, and ink is ejected from the nozzle 40 communicating with the pressure chamber 34.

  Next, the suction cap device 13 will be described. FIG. 3 is a plan view of the suction cap device. 4 is a cross-sectional view taken along line AA in FIG. FIG. 5 is a longitudinal sectional view of the vicinity of the suction cap device when the suction cap device is located at the retracted position. FIG. 6 is a longitudinal sectional view of the vicinity of the suction cap device when the suction cap device is located at the capping position.

  As shown in FIG. 1, the suction cap device 13 is an area outside the print area facing the recording paper P (right side in FIG. 1) (hereinafter referred to as a maintenance position) within the movement range of the carriage 2 in the scanning direction. ) And faces the ink ejection surface 38 of the inkjet head 3 when the carriage 2 has moved to the maintenance position.

  As shown in FIGS. 3 and 4, the suction cap device 13 includes a cap 60 made of an elastic member such as rubber capable of covering the ink discharge surface 38, and two cap chips 67 housed in the cap 60. 68, a cap holder 63 for holding the cap 60, and a suction pump 14 (suction means).

  The cap 60 has a rectangular bottom wall 69 in plan view, an annular side wall 70 standing along the edge of the bottom wall 69, an annular lip 76 further projecting from the upper end of the side wall 70, and the bottom wall 69. The partition wall 78 is erected and has a lip 79 further protruding from the upper end of the partition wall 78.

  The partition wall 78 extends along the paper feed direction so as to connect the middle portions of the side walls 70 along the scanning direction, and includes a bottom wall 69 and an annular side wall 70, and has a rectangular shape opened upward. Are divided into two for black ink and for three color inks (cyan, magenta, yellow). Among the two divided recesses, the bottom surface of the rectangular recess 61 in plan view located on the left side of FIG. 3 shows black ink in plan view when the inkjet head 3 has moved to the maintenance position. Opposite the area overlapping the nozzle 40 to be discharged. Further, the bottom surface of the concave portion 62 that is rectangular in a plan view located on the right side of FIG. 3 includes a nozzle 40 that ejects three color inks in a plan view when the inkjet head 3 has moved to the maintenance position. Opposite the overlapping area. A part of the bottom wall 69 constituting the recess 61 is a bottom wall 69a, and a part of the bottom wall 69 constituting the recess 62 is a bottom wall 69b. The lip 79 extends along the paper feed direction so as to connect the middle portions of the lips 76 along the scanning direction, and divides the region partitioned by the lip 76 into two.

  Since the bottom wall 69, the side wall 70, and the lips 76, 79 constituting the cap 60 are integrally formed of an elastic member, the bottom wall and the side wall are formed of a plate member made of resin, and the ink discharge surface 38 is formed. The bottom wall 69, the side wall 70, and the lip 76 in this embodiment are formed as compared with the case where only the lip is formed of an elastic member to improve the adhesiveness of the resin and the lip made of the elastic member is joined to the side wall made of resin with an adhesive or the like. , 79 are integrally formed and have no joints, so that the lips 76, 79 are in close contact with the ink discharge surface 38 and are defined by the bottom wall 69, the side wall 70, the lips 76, 79 and the ink discharge surface 38. It is easy to maintain the sealed state of the space.

  A suction hole 71 that penetrates in the thickness direction is formed in the bottom wall 69a. Cap chips 67, which protrude in parallel with the scanning direction and are disposed in the recesses 61, 62 on the inner part along the paper feed direction at the tip of the side wall 70 and on both sides of the tip of the partition wall 78. A convex portion 72 is formed in contact with the edge along the paper feeding direction on the upper surface of 68. The convex portion 72 is in contact with the edges of the upper surfaces of the cap chips 67 and 68 to prevent the cap chips 67 and 68 from being pushed up toward the ink discharge surface 38.

  The cap holder 63 has a concave shape opened upward, and the cap 60 is fitted and held in the concave portion. Further, the cap holder 63 has a through hole 63a formed at a position overlapping the suction hole 71 of the bottom wall 69a in a plan view, and a through hole 63b formed at a position overlapping the suction hole 73 of the bottom wall 69b. Has been. The cap holder 63 is connected to the support member 80 via a spring 81 connected to the bottom surface. From the bottom surface of the cap holder 63, an L-shaped hook 63 c extends downward toward the support member 80.

  The support member 80 is connected to the elevating mechanism 65 and is movable in the vertical direction together with the cap holder 63 and the cap 60 connected via the spring 81. Further, the support member 80 has a side wall 80 a extending upward on the side of the cap holder 63. The side wall 80a is formed with an opening 80b for hooking the hook 63c in a state where the cap holder 63 is pressed downward and the spring 81 is contracted to some extent.

  The cap 60 is moved up and down by the support mechanism 80 by the elevating mechanism 65, and the tips of the lips 76 and 79 are brought into close contact with the ink discharge surface 38. 62 is movable between a capping position where two sealed spaces are demarcated by 62 and a retracted position retracted from the capping position.

  As shown in FIG. 5, when the cap 60 is located at the retracted position, the spring 81 is about to extend, and the cap 60 is moved by bringing the hook 63 c of the cap holder 63 into contact with the upper surface of the opening 80 b of the support member 80. The movement of 81 to the position where 81 is extended is restricted.

  Further, as shown in FIG. 6, when the cap 60 is moved from the retracted position to the capping position, the tips of the lips 76 and 79 are in close contact with the ink discharge surface 38, and the upward movement of the cap 60 is restricted. Only the support member 80 shrinks the spring 81 and pushes it upward, and the opening 80b formed in the support member 80 moves upward, so that the hook 63c of the cap holder 63 contacts the upper surface of the opening 80b of the support member 80. Disappear.

  As described above, the hook 63c of the cap holder 63 repeats contact with the upper surface of the opening 80b of the support member 80 every time the cap 60 alternately moves between the capping position and the retracted position. It must be made of a strong material. The hook 63c can be easily integrally formed with the concave portion of the cap holder 63 by injection molding. Therefore, the cap holder 63 including the hook 63c is formed of polyacetal having excellent wear resistance.

  The suction hole 71 formed in the bottom wall 69a and the suction hole 73 formed in the bottom wall 69b are passed through the through holes 63a and 63b formed in the cap holder 63 and the two tubes 11a and 11b. The suction pump 14 is connected via a switching unit 15.

  The cap chip 67 is made of synthetic resin, has a rectangular shape, and is accommodated in the recess 61 of the cap 60. The cap chip 67 is formed with a through hole 67a penetrating in the thickness direction. In addition, a groove 67b that extends along the paper feed direction and communicates with the through hole 67a is formed on the surface of the cap chip 67 that faces the ink ejection surface 38. On the back surface of the cap chip 67 facing the bottom wall 69a of the cap 60, two grooves 67c extending along the paper feeding direction with the groove 67b interposed therebetween are formed. The two grooves 67c communicate with each other via a groove 67d extending along the scanning direction. The groove 67d communicates with the through hole 67a.

  Further, the edge of the surface of the cap chip 67 along the paper feeding direction is provided with a protrusion 74 that extends along the paper feeding direction and has a rounded tip 74a. The protrusion 74 is made of synthetic resin except for the tip portion 74a, and only the tip portion 74a is formed of an elastic member such as rubber. That is, the elastic modulus of the tip 74a of the protrusion 74 is smaller than the elastic modulus of the portion excluding the tip 74a. When the inkjet head 3 has moved to the maintenance position, the protrusion 74 opposes the position on the ink ejection surface 38 where the nozzle 40 is formed and the position excluding the vicinity thereof.

  Further, the length of one side along the scanning direction of the recess 61 is substantially the same as the length of one side along the scanning direction of the cap chip 67. The length of the other side along the paper feeding direction of the recess 61 is longer than the length of the other side along the paper feeding direction of the cap chip 67. That is, the side surface along the scanning direction of the cap chip 67 accommodated in the recess 61 is not in contact with the side wall 70 along the scanning direction, and the both sides of the cap chip 67 in the paper feeding direction are along the scanning direction. An extended gap is formed.

  Similar to the cap chip 67, the cap chip 68 is made of a synthetic resin or the like, has a rectangular shape, and is accommodated in the recess 62 of the cap 60. The cap chip 68 is formed with three through holes 68a penetrating in the thickness direction along the scanning direction. Further, on the surface of the cap chip 68 facing the ink ejection surface 38, three grooves 68b extending along the paper feeding direction and communicating with the respective through holes 68a are formed along the scanning direction. On the back surface of the cap chip 68 facing the bottom wall 69b of the cap 60, four grooves 68c are formed along the scanning direction so as to be alternately aligned with the grooves 68b and extend along the paper feed direction. The four grooves 68c communicate with each other via a groove 68d extending along the scanning direction. The groove 68d communicates with the three through holes 68a.

  Further, at the edge portion along the paper feeding direction on the surface of the cap chip 68, a protrusion 75 extending along the paper feeding direction and having a rounded tip 75a is provided. The protrusion 75 is made of synthetic resin except for the tip portion 75a, and only the tip portion 75a is made of an elastic member such as rubber. That is, the elastic modulus of the tip 75a of the protrusion 75 is smaller than the elastic modulus of the portion excluding the tip 75a. When the ink jet head 3 has moved to the maintenance position, the protrusion 75 faces the position excluding the position where the nozzle 40 is formed on the ink ejection surface 38 and the vicinity thereof.

  Further, the length of one side along the scanning direction of the recess 62 is substantially the same as the length of one side along the scanning direction of the cap chip 68. The length of the other side along the paper feeding direction of the recess 62 is longer than the length of the other side along the paper feeding direction of the cap chip 68. That is, the side surface along the scanning direction of the cap chip 68 accommodated in the recess 62 is not in contact with the side wall 70 along the scanning direction, and the both sides of the cap chip 68 in the paper feeding direction are along the scanning direction. An extended gap is formed.

  As shown in FIG. 6, the inkjet head 3 has moved to the maintenance position, and the support member 80 is moved upward (front side in FIG. 1) by the lifting mechanism 65, so that the cap holder 63 and the cap 60 are moved upward. The tip ends of the lips 76 and 79 are brought into close contact with the ink discharge surface 38. Two sealed spaces are defined by the ink discharge surface 38, the lips 76 and 79, and the recesses 61 and 62 of the cap 60. At this time, the tip portions 74 a and 75 a of the protrusions 74 and 75 formed on the cap chips 67 and 68 are in contact with positions that do not face the nozzle 40 and the vicinity thereof on the ink discharge surface 38.

  When the suction pump 14 is operated in a state where the tips of the lips 76 and 79 formed on the cap 60 are in close contact with the ink discharge surface 38, the sealed space is sucked under reduced pressure, and ink is sucked from the nozzle 40. To purge. At this time, the switching unit 15 switches the communication destination of the suction pump 14 between the suction hole 71 and the suction hole 73, so that either the nozzle 40 for discharging black ink or the nozzle 40 for discharging color ink is selected. One can be selected to suck ink. As a result, the ink in the nozzle 40 whose viscosity has been increased (thickened) due to drying is discharged, or bubbles mixed in the ink flow path of the inkjet head 3 or in the further upstream sub tank 4 are combined with the ink. It is possible to recover the ink discharge performance of the inkjet head 3 by discharging the ink from 40.

  Then, the driving of the suction pump 14 is stopped, the suction of ink from the nozzle 40 is stopped, and the cap 60 is separated from the ink discharge surface 38 in a state where the ink is received in the recesses 61 and 62 to be sealed. In the state where the space is opened, the ink sucked from the nozzle 40 by the purge process and received in the concave portions 61 and 62 of the cap 60 is driven again to discharge the ink from the suction holes 71 and 73 to a discharge tank (not shown). (So-called empty suction operation).

  At this time, the ink received on the surfaces of the cap chips 67 and 68 in the recesses 61 and 62 of the cap 60 passes through the gaps on both sides of the cap chips 67 and 68 and through holes 67a and 68a formed in the cap chips 67 and 68. To the back of the cap chips 67 and 68. Ink that is not received in the gaps on both sides of the cap chips 67 and 68 and in the vicinity of the through holes 67a and 67b formed in the cap chips 67 and 68 is formed in the grooves 67b and 68b. , 68b and flows quickly toward the gaps on both sides of the cap chips 67, 68 and the through holes 67a, 67b. The ink that has flowed to the back surfaces of the cap chips 67 and 68 quickly flows toward the suction holes 71 and 73 via the grooves 67c and 68c and the grooves 67d and 68d.

  As described above, since the protrusions 74 and 75 are formed at the edges of the cap chips 67 and 68 along the paper feeding direction, the ink received on the surfaces of the cap chips 67 and 68 flows along the paper feeding direction. Thus, the flow into the gaps on both sides of the cap chips 67 and 68 is not hindered.

  When the sealed space is depressurized by the suction operation by the suction pump 14 in the purge process, the pressure in the sealed space becomes lower than the pressure outside the sealed space. Then, the cap 60 is easily deformed because it is formed of an elastic member, and the bottom wall 69 having the largest surface area of the cap 60 is deformed toward the sealed space. The cap chips 67 and 68 are pushed up toward the ink discharge surface 38 and come into contact with the ink discharge surface 38, thereby inhibiting the discharge of ink from the nozzle 40. In addition, an ink repellent film made of a fluorine-based resin for preventing ink adhesion is formed on the ink ejection surface 38 of the nozzle plate 33. The cap chips 67 and 68 come into contact with the ink-repellent film near the nozzle 40 to damage the ink-repellent film or damage the nozzle 40 itself, thereby causing the ejection direction from the nozzle 40 to shift or cause ejection failure. End up.

  Therefore, the convex portions 72 formed on the side wall 70 come into contact with the edges of the upper surfaces of the cap chips 67 and 68 to prevent the cap chips 67 and 68 from being pushed up toward the ink discharge surface 38. However, when the sealed space of the cap 60 is further depressurized and the pressure difference between the sealed space and the outside increases, the bottom wall 69 is deformed to the ink ejection surface 38 side, and the lip 76, 79 opens to the outside, and the restriction of the cap chips 67 and 68 by the convex portion 72 formed on the side wall 70 is released.

  In the present embodiment, protrusions 74 and 75 are formed at positions that do not face the nozzle 40 of the cap chips 67 and 68 and the vicinity thereof. Therefore, even when the cap chips 67 and 68 are pushed up toward the ink discharge surface 38, the protrusions 74 and 75 come into contact with the nozzle 40 on the ink discharge surface 38 and a position that does not oppose the vicinity thereof, and the cap chip 67, Since 68 does not contact, the ink discharge surface 38, especially the nozzle 40, can be protected. At this time, the tip portions 74a and 75a of the protrusions 74 and 75 are rounded and formed of an elastic member, so that when the ink comes into contact with a position not facing the nozzle 40 on the ink discharge surface 38, the ink is discharged. The discharge surface 38 is not easily damaged.

  Further, when the cap 60 is moved to the capping position, the tip portions 74a and 75a of the protrusions 74 and 75 formed on the cap chips 67 and 68 are not in contact with the nozzle 40 on the ink discharge surface 38 and the vicinity thereof. Since they are in contact with each other, the bottom wall 69 of the cap 60 is not deformed to the sealed space side, suction loss due to the suction pump 14 is eliminated, and ink discharge from the nozzles 40 can be started quickly. Further, since the projections 74 and 75 are formed at the edge portions of the cap chips 67 and 68 along the paper feeding direction, a portion along the scanning direction along the paper feeding direction due to the pressure difference between the sealed space and the outside. The protrusions 74 and 75 can prevent the lips 76 and 79 that are easily deformed for a longer time from bending toward the sealed space.

  It is also conceivable that the upper surface of the cap holder 63 and the lower surface of the bottom wall 69 of the cap 60 are adhered with an adhesive or the like so that the bottom wall 69 of the cap 60 does not deform toward the sealed space in the purge process. However, in this case, the cost of the adhesive and the process of bonding the cap holder 63 and the cap 60 are required. Further, the cap holder 63 is made of polyacetal so as not to be worn out. However, this polyacetal is generally a material that is difficult to bond, and it is difficult to bond the cap holder 63 and the cap 60 together. Furthermore, since the cap 60 is formed of an elastic member such as rubber, the cap 60 becomes hard when deteriorated, and the capping performance cannot be maintained. Therefore, it is necessary to replace the cap 60. However, if the cap 60 is bonded to the cap holder 63, this replacement operation becomes complicated, so that it is inappropriate to bond the cap holder 63 and the cap 60. .

<Second Embodiment>
Next, a preferred second embodiment of the present invention will be described. The second embodiment is the same as the first embodiment except for the configurations of the cap chips 67 and 68 and the nozzle plate 33 in the first embodiment. Components similar to those in the first embodiment are denoted by the same reference numerals and description thereof is omitted. In the second embodiment, a convex portion for preventing the cap chip from contacting is formed not on the cap chip but on the ink ejection surface side.

  FIG. 7 is a longitudinal sectional view when the suction cap device according to the second embodiment covers the ink discharge surface. As shown in FIG. 7, the cap chips 267 and 268 in the second embodiment are the same except for the protrusions 74 and 75 formed on the cap chips 67 and 68 in the first embodiment. . Further, rubber or the like is provided at a position where the nozzle 40 is not formed on the ink ejection surface 238 of the nozzle plate 233 and when the inkjet head 3 moves to the maintenance position, the position facing the cap chips 67 and 68. The convex part 238a which consists of an elastic member is formed.

  Next, the purge process will be described. The ink-jet head 3 has moved to the maintenance position, and the cap holder 63 has been moved upward (front side in FIG. 1) by the elevating mechanism 65, so that the cap 60 has moved upward and the tips of the lips 76, 79 have been moved. Adheres closely to the ink ejection surface 238. Two sealed spaces are defined by the ink discharge surface 238, the lips 76 and 79, and the recesses 61 and 62 of the cap 60. When the sealed space is depressurized by the suction operation by the suction pump 14, the pressure in the sealed space becomes lower than the pressure outside the space. Then, the cap 60 is easily deformed because it is formed of an elastic member, and the bottom wall 69 having the largest surface area of the cap 60 is deformed toward the sealed space. The cap chips 67 and 68 are pushed up toward the ink discharge surface 38.

  However, in the present embodiment, when the inkjet head 3 has moved to the maintenance position at a position where the nozzles 40 are not formed on the ink ejection surface 238 of the nozzle plate 233, the cap chips 67 and 68 are opposed to each other. A convex portion 238a is formed at the position. Therefore, even if the cap chips 67 and 68 are pushed up toward the ink discharge surface 238, the convex portion 238 a contacts the cap chips 67 and 68, and the cap chips 67 and 68 do not contact the nozzle 40. The discharge surface 38, particularly the nozzle 40 can be protected.

  Next, modified embodiments in which various modifications are added to the embodiment will be described. However, components having the same configuration as in the above embodiment are given the same reference numerals and description thereof is omitted as appropriate.

  In the present embodiment, the protrusions 74 and 75 extending along the paper feed direction are formed at the edges of the cap chips 67 and 68 along the paper feed direction. However, as shown in FIG. The plurality of protrusions 174 and 175 may be formed along the edges of the cap chips 167 and 168 at intervals. According to this, even if the protrusion is formed at the edge along the scanning direction in which the ink flows, the protrusion does not hinder the ink flow because the protrusion has a rod shape.

  A plurality of through holes penetrating in the thickness direction may be formed on the entire surface of the cap chips 67 and 68. In this case, since the ink received on the surfaces of the cap chips 67 and 68 from the plurality of through holes flows on the back surfaces of the cap chips 67 and 68, no gap is formed on both sides of the cap chips 67 and 68 in the paper feeding direction. May be. At this time, annular projections may be formed along the edges of the cap chips 67 and 68. In addition, grooves may not be formed on the surfaces of the cap chips 67 and 68.

  Further, the protrusions formed on the cap chips 67 and 68 are not limited to the edge portions and may be formed at any position as long as the protrusions are not opposed to the nozzles 40 formed on the ink discharge surface 38.

  Further, in the present embodiment, the cap 60 has the side wall 70 standing from the bottom wall 69 to form a recess, and the lip 76 protrudes from the side wall 70. A lip projecting directly from the wall may form a recess for receiving ink.

  In the present embodiment, the support member 80 connected to the cap holder 63 holding the cap 60 via the spring 81 is connected to the lifting mechanism 65, and the lifting member 65 is driven to lift and lower the support member 80. The cap 60 is moved up and down, but the cap holder 63 and the support member 80 may not be provided. In this case, the cap 60 is directly connected to the lifting mechanism 65 and the cap 60 is directly driven to lift by the lifting mechanism 65. You may let them.

  Further, if the cap 60 is formed of an elastic member such as rubber, only the lip 76 contacting the ink discharge surface 38, the bottom wall 69 may be a resin plate, a metal plate, or the like.

  In the embodiment described above, the present invention is applied to the suction cap device 13 provided in the serial printer, but the application target of the present invention is a suction cap device provided in the line printer. There may be. Further, the application target of the present invention is not limited to an ink jet printer, and the present invention is applied to suction cap devices provided in various liquid ejection devices that eject various types of liquids to the target according to the application. Is possible.

1 is a plan view illustrating a schematic configuration of a printer according to a first embodiment. It is a vertical sectional view of a part of an inkjet head. It is a top view of a suction cap device. FIG. 4 is a sectional view taken along line AA in FIG. 3. It is a longitudinal cross-sectional view of the vicinity of the suction cap device when the suction cap device is located at the retracted position. It is a longitudinal cross-sectional view of the suction cap apparatus vicinity when a suction cap apparatus is located in a capping position. It is a longitudinal cross-sectional view when the suction cap apparatus in 2nd Embodiment has covered the ink discharge surface. It is a top view of the suction cap apparatus in a modification.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Printer 3 Inkjet head 13 Suction cap apparatus 14 Suction pump 38 Ink discharge surface 40 Nozzle 60 Cap 69 Bottom wall 70 Side wall 72 Convex part 74, 75, 174, 175 Protrusion 76, 79 Lip 67, 68, 167, 168, 267, 268 cap chip

Claims (11)

A cap member having a bottom wall portion facing the liquid ejection surface of the liquid ejection head, and an annular lip that can be brought into close contact with the liquid ejection surface provided to protrude from the bottom wall portion toward the liquid ejection surface;
A suction means that communicates with the internal space of the cap member and sucks the internal space;
A cap chip disposed in the internal space of the cap member,
When the lip is capped in close contact with the liquid discharge surface, a protrusion is formed at a position on one surface opposite to the bottom wall portion of the cap chip that does not face the discharge port formed on the liquid discharge surface. A suction cap device, wherein:   The suction cap device according to claim 1, wherein the bottom wall portion and the lip constituting the cap member are made of an elastic member and are integrally molded.   The suction cap device according to claim 1, wherein a tip end portion of the protrusion is rounded.   The suction cap device according to any one of claims 1 to 3, wherein an elastic modulus of a tip portion of the protrusion is smaller than an elastic modulus of a portion excluding the tip portion. And a moving mechanism for moving the cap member between a capping position where the lip is in close contact with the liquid discharge surface and a suction operation is performed by the suction means, and a retracted position retracted from the capping position. And
5. The device according to claim 1, wherein when the cap member is moved to the capping position by the moving mechanism, the tip end portion of the protrusion comes into contact with a position not facing the discharge port of the liquid discharge surface. The suction cap device according to claim 1.   The suction cap device according to claim 1, wherein the protrusion is formed on an edge portion of the one surface of the cap chip. The protrusion has a rod shape and a plurality of protrusions are provided,
The suction cap device according to claim 6, wherein the plurality of protrusions are arranged at intervals on an edge portion of the one surface of the cap chip. When viewed from the direction orthogonal to the bottom wall portion, the internal space of the cap member is partitioned into a rectangular shape by the lip, and the cap chip is disposed in the internal space and is orthogonal to the direction. It has a rectangular shape as seen from
The length of one side of the cap chip is substantially the same as the length between two opposite sides of the lip that is orthogonal to the one side of the cap chip;
The length of the other side orthogonal to the one side of the cap chip is shorter than the length between the two sides orthogonal to the two sides of the lip,
The suction cap device according to claim 6, wherein the protrusion is formed at the edge portion of the cap chip that is located at both ends of the cap chip with respect to the direction in which the one side extends.   The suction cap device according to claim 8, wherein a groove extending in parallel with the other side of the cap chip is formed on the one surface of the cap chip. An interior of a cap member having a bottom wall portion facing the liquid ejection surface of the liquid ejection head, and an annular lip that protrudes from the bottom wall portion toward the liquid ejection surface and can be in close contact with the liquid ejection surface A cap chip contained in a space,
A chip body;
When the lip is capped in close contact with the liquid discharge surface, the chip body is erected at a position not facing the discharge port formed on the liquid discharge surface on one surface opposite to the bottom wall portion of the chip body. And a cap chip. A liquid ejection head that ejects liquid from an ejection port formed on the liquid ejection surface;
A suction cap device capable of capping the liquid discharge surface of the liquid discharge head,
The suction cap device includes:
A cap member having a bottom wall portion facing the liquid ejection surface of the liquid ejection head, and an annular lip that can be brought into close contact with the liquid ejection surface provided to protrude from the bottom wall portion toward the liquid ejection surface;
A suction means that communicates with the internal space of the cap member and sucks the internal space;
A cap chip disposed in the internal space of the cap member,
The liquid ejection apparatus, wherein the liquid ejection surface has a convex portion at a position where the ejection port is not formed.

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