JP2010149369A - Suction cap apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent a cap member from being deformed and being separated from a liquid delivering face during sucking. <P>SOLUTION: A suction cap apparatus 13 provided on a printer includes: a cap 60 consisting of a bottom wall 69 opposing an ink delivering face 38 and a lip 76 which projects from the bottom wall 69 through a sidewall 70 and can come into close contact with the ink delivering face 38; a suction pump 14 for sucking the internal space of the cap 60; and a cap holder 63 for supporting the bottom wall 69. When the lip 76 comes into close contact with the ink delivering face 38 to perform capping, the suction pump 14 sucks the internal space of the cap 60, and sucks a space between the bottom wall 69 and the cap holder 63 to attract the bottom wall 69 to the cap holder 63. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a suction cap device provided in a liquid ejection device.

  In general, a liquid discharge apparatus having a liquid discharge head for discharging a liquid covers a liquid discharge surface on which the nozzles of the liquid discharge head are formed in order to eliminate defective discharge of the nozzles formed on the liquid discharge head. A suction cap device for sucking liquid from the nozzle is provided. For example, a suction cap device in an ink jet recording apparatus described in Patent Document 1 includes a cap member that can cover a liquid discharge surface of a liquid discharge head, and suction means such as a suction pump connected to the cap member. Yes. Then, the suction cap device covers the liquid discharge surface with the cap member during the purge process to eliminate the defective discharge of the nozzle, and discharges bubbles or thickened liquid sucked from the nozzle by driving the suction pump to the cap member. To do.

Japanese Patent Laying-Open No. 2007-90807 (FIG. 14)

  However, if 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, and the bottom wall with the largest surface area of the cap member is liquid due to the pressure difference from the outside of the cap member It will be deformed to the discharge surface side. Then, with the deformation of the bottom wall, the cap member is separated from the liquid discharge surface, and a gap is formed between the cap member and the liquid discharge surface, so that the liquid leakage from the cap member and the sealed state are released. There is a risk of insufficient purge.

  Therefore, an object of the present invention is to provide a suction cap device that can prevent the cap member from being deformed and separated from the liquid ejection surface during suction.

  The suction cap device of the present invention includes a bottom wall portion facing a liquid discharge surface of a liquid discharge head, and an annular lip that protrudes from the bottom wall portion toward the liquid discharge surface and can be in close contact with the liquid discharge surface A cap member that communicates with the internal space of the cap member, sucks the internal space, a support member that supports the bottom wall portion of the cap member, and a tip of the lip is the liquid A suction means for sucking the bottom wall portion to the support member when a suction operation is performed by the suction means in a capping state in close contact with the discharge surface.

  According to the suction cap device of the present invention, when the suction operation by the suction means is performed with the tip of the lip in close contact with the liquid discharge surface, the internal space of the cap member is depressurized, and the air pressure in the internal space is reduced to the cap member. Even when the pressure is lower than the outside air pressure, the bottom wall portion is adsorbed to the support member by the adsorbing means, and therefore is not easily deformed to the liquid ejection surface side. Therefore, it is possible to prevent the tip of the lip from moving away from the liquid discharge surface as the cap member deforms the bottom wall.

  The bottom wall portion and the lip constituting the cap member are made of an elastic member and integrally molded. Since the elastic member has a low elastic modulus, when the bottom wall portion is made of an elastic member together with the lip, the bottom wall portion is easily deformed, and the present invention is effective.

  Further, the bottom wall portion is formed in a flat plate shape, and the support member has a flat support surface that contacts a contact surface opposite to a surface of the bottom wall portion facing the liquid discharge surface, The adsorption means preferably adsorbs the entire contact surface of the bottom wall portion to the support surface of the support member. According to this, since the adhesive surface of the bottom wall portion and the support surface of the support member are flat with each other, the bottom wall portion is entirely adsorbed by the support member, and the holding effect of the cap member is enhanced.

  Further, the support member is formed with a suction hole that opens toward the bottom wall, and the suction means is connected to the other end of the suction hole opposite to the one end on the bottom wall side. Then, it is preferable that the bottom wall portion is sucked to the support member by sucking a space between the bottom wall portion and the support member through the suction hole. According to this, the entire surface of the bottom wall portion can be adsorbed to the support member with a uniform adsorbing force with a simple configuration.

  In addition, it is preferable that the suction means also serves as the suction means for sucking the bottom wall portion to the support member through the suction holes of the support member. According to this, the inside space of the cap member can be sucked with one suction means, and the space between the bottom wall portion and the support member can be sucked.

  A switching means for switching whether the suction means communicates only with the internal space of the cap member, or communicates with both the internal space and the space between the bottom wall portion and the support member; A capping position where the tip of the lip is in a capping state where the tip of the lip is in close contact with the liquid ejection surface, and a moving mechanism for moving the cap member over a retreat position retracted from the capping position, The switching means causes the suction means to communicate with only the internal space when the cap member is positioned at the retracted position by the moving mechanism, and the cap member is positioned at the capping position by the moving mechanism. The suction means communicates with both the internal space and the space between the bottom wall portion and the support member. It is preferred. According to this, the cap member does not cover the liquid discharge surface, and the cap member has an open inner space, so that the liquid received in the cap member is sucked and discharged by the suction means. When there is no possibility that the wall portion is deformed, the suction means is connected only to the internal space, so that the suction means depends on the internal space and the space between the bottom wall portion and the support member. All the suction force acts on the suction of the liquid received in the cap member, the suction force for the liquid is increased, and the liquid received in the cap member can be quickly sucked.

  Furthermore, it is preferable that a cap chip is accommodated in the internal space of the cap member. According to this, since the bottom wall portion is not deformed to the liquid discharge surface side, the cap chip is pushed up toward the liquid discharge surface along with the deformation of the bottom wall portion, thereby preventing contact with the liquid discharge surface. Can do.

  It is possible to prevent the tip of the lip from moving away from the liquid discharge surface as the cap member deforms the bottom wall.

  Next, a preferred 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 a printer according to the present embodiment. As shown in FIG. 1, the printer 1 includes a carriage 2 configured to be reciprocally movable along one direction, an ink jet 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. 5 is a cross-sectional view taken along line BB in FIG. FIG. 6 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. 7 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 to 5, 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 (support member) for holding the cap 60, and a suction pump 14 (suction means).

  The cap 60 is integrally molded and has a bottom wall 69 that is rectangular in plan view, an annular side wall 70 that stands up along the edge of the bottom wall 69, and an annular lip 76 that further protrudes from the upper end of the side wall 70. And a partition wall 78 erected from the bottom wall 69, and 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 intermediate portions of the side walls 70 along the scanning direction. The partition wall 78 is composed of a bottom wall 69 and an annular side wall 70, and has a rectangular recess opened upwards for two for black ink and three color inks (cyan, magenta, yellow). It is divided.

  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, the partition wall 78, and the lips 76, 79 constituting the cap 60 are integrally formed by an elastic member, only the lip is an elastic member in order to improve the adhesion to the ink discharge surface 38. Compared to the case where the bottom wall and the side wall excluding the lip are formed of a plate member made of resin, etc., and the lip made of an elastic member is joined to the side wall made of resin with an adhesive or the like to constitute a cap. No bonding process is required. The cap 60 can be easily formed integrally by injection molding or the like. Further, since the cap 60 is integrally formed and has no joint portion, when the lips 76 and 79 are in close contact with the ink ejection surface 38 and capped, the bottom wall 69, the side wall 70, the partition wall 78, and the lips 76 and 79 are provided. In addition, it is easy to maintain the sealed state of the space defined by the ink discharge surface 38.

  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 part 72 is in contact with the edge of the upper surface of the cap chips 67 and 68 and restricts the upward movement of the cap chips 67 and 68.

  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. Further, the cap holder 63 has a through hole 63c formed at a position overlapping the central portion of the bottom wall 69a in a plan view, and a through hole 63d formed at a position overlapping the central portion of the bottom wall 69b. Yes. The cap holder 63 is connected to the holding 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 holding member 80.

  The holding 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. The holding 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 capped with the tips of the lips 76 and 79 in close contact with the ink ejection surface 38 as the holding member 80 is moved up and down by the elevation mechanism 65, so that the ink ejection surface 38, the lips 76 and 79, and The cap 60 can move between a capping position in which two sealed spaces are defined by the recesses 61 and 62 and a retreat position retracted from the capping position.

  As shown in FIG. 6, when the cap 60 is in the retracted position, the spring 81 tends to extend upward, but the hook 63 c of the cap holder 63 comes into contact with the upper surface of the opening 80 b of the holding member 80, thereby 81 is restricted from extending completely.

  Further, as shown in FIG. 7, 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 stopped. Only the holding member 80 shrinks the spring 81 and pushes it upward, and the opening 80b formed in the holding member 80 moves upward, so that the hook 63c of the cap holder 63 contacts the upper surface of the opening 80b of the holding 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 holding member 80 every time the cap 60 alternately moves between the capping position and the retracted position. It is necessary to be formed with. 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 communicate with the through holes 63a and 63b formed in the cap holder 63, and are connected to the through holes 63a and 63b. It is connected to the suction pump 14 via the switching unit 15 via the tube 11b. Moreover, the through holes 63c and 63d formed in the cap holder 63 are connected to the suction pump 14 via the switching unit 15 via the tube 11a. The switching unit 15 switches whether the suction pump 14 communicates only with the tube 11b or whether the suction pump 14 communicates with both the two tubes 11a and 11b.

  When the suction pump 14 is driven in a state where the suction pump 14 and the tube 11b communicate with each other, the suction holes 71 and 73 formed in the bottom wall 69a, the through holes 63a and 63b formed in the cap holder 63, and the tube 11b are used. Then, the recesses 61 and 62 of the cap 60 are sucked. Further, when the suction pump 14 is driven in a state where the suction pump 14 and the tube 11a communicate with each other, the gap between the bottom wall 69 and the cap holder 63 via the through holes 63c and 63d formed in the cap holder 63 and the tube 11a. The entire lower surface 69c (contact surface) of the bottom wall 69 is attracted to the upper surface 63e (support surface) of the cap holder 63. At this time, since the lower surface 69c of the bottom wall 69 and the upper surface 63e of the cap holder 63 are flat with each other, the bottom wall 69 is entirely adsorbed by the cap holder 63, and the holding effect of the cap 60 by the cap holder 63 is enhanced. . Further, the entire lower surface 69 of the bottom wall 69 can be adsorbed to the upper surface 63e of the cap holder 63 with a uniform adsorbing force with a simple configuration.

  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.

  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 70a 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.

  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 70b 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. 7, the ink-jet head 3 has moved to the maintenance position, and the holding member 80 has been moved upward (front side in FIG. 1) by the elevating 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.

  When the suction pump 14 is driven 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 of the cap 60 is sucked under reduced pressure, and the ink is discharged from the nozzle 40. A purge process for sucking and discharging the gas is performed. 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, by stopping the driving of the suction pump 14, the suction of the 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. With the sealed space opened, the ink sucked from the nozzle 40 by the purge process and received in the recesses 61 and 62 of the cap 60 is driven again to the discharge tank (not shown) from the suction holes 71 and 73 by driving the suction pump 14. Discharge (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.

  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 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. With the deformation of the bottom wall 69, the entire cap 60 is deformed, the tips of the lips 76 and 79 are separated from the ink discharge surface 38, and a gap is formed between the lips 76 and 79 and the ink discharge surface 38. As a result, ink may not be sucked from the nozzles 40.

  In addition, even if the bottom wall 69 is deformed and the tips of the lips 76 and 79 are not separated from the ink discharge surface 38, the cap chips 67 and 68 are moved along with the deformation of the bottom wall 69 toward the ink discharge surface 38. The ink is pushed up toward the ink ejection surface 38 and comes into contact with the ink ejection surface 38, thereby hindering ink discharge 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, and the cap chips 67 and 68 are in contact with the ink repellent film near the nozzle 40. If the ink repellent film is damaged or the nozzle 40 itself is damaged, the ejection direction from the nozzle 40 may be shifted or the ejection may be defective.

  Therefore, in the present embodiment, during the purge process, the switching unit 15 makes the communication destination of the suction pump 14 both the two tubes 11a and 11b. As described above, when the suction pump 14 performs a suction operation as a purge process in a state where the suction pump 14 communicates with both the two tubes 11a and 11b, the through holes 63c and 63d formed in the cap holder 63 and The space between the bottom wall 69 and the cap holder 63 is sucked through the tube 11a. Then, the lower surface 69c of the bottom wall 69 is attracted to the upper surface 63e of the cap holder 63, and the posture of the cap 60 including the bottom wall 69 is held in a capping posture.

  Therefore, even if the sealed space of the cap 60 is depressurized and the atmospheric pressure in the sealed space becomes lower than the external atmospheric pressure, the bottom wall 69 is difficult to deform, and the entire cap 60 is deformed, so that the tips of the lips 76 and 79 are deformed. Can be prevented from separating from the ink discharge surface 38. Further, since the bottom wall 69 is not deformed toward the ink discharge surface 38, the cap chips 67 and 68 are pushed up toward the ink discharge surface 38 along with the deformation of the bottom wall 69, and come into contact with the ink discharge surface 38. Can be prevented. Further, with one suction pump 14, both suction of the sealed space and suction of the bottom wall 69 to the cap holder 63 can be performed.

  Further, since the cap 60 is separated from the ink discharge surface 38 during idle suction, the inner space of the cap 60 is not sealed, and the bottom wall 69 is not deformed by the decompression of the inner space of the cap 60. The switching unit 15 makes the communication destination of the suction pump 14 only the tube 11b. That is, the space between the bottom wall 69 and the cap holder 63 is not sucked, but only the space inside the cap 60 is sucked. As a result, all of the suction force by the suction pump 14 acts on the suction of the ink received in the cap 60, the suction force for the ink is increased, and the ink received in the cap 60 can be quickly sucked. .

  In the manufacturing stage, the upper surface 63e of the cap holder 63 and the lower surface 69c of the bottom wall 69 of the cap 60 are bonded from the beginning with an adhesive or the like, and the bottom wall 69 of the cap 60 does not deform toward the sealed space in the purge process. Although it is conceivable to do so, the cost of the adhesive and the step 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 capping performance cannot be maintained if it becomes hard due to deterioration over time. 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. .

  Next, modified embodiments in which various modifications are added to the above-described embodiment will be described. However, those having the same configuration as that of the above-described embodiment are denoted by the same reference numerals and description thereof is omitted as appropriate.

  In the present embodiment, the switching unit 15 as switching means switches whether the suction pump 14 communicates with both the two tubes 11a and 11b or communicates only with the tube 11b. A valve may be provided in the middle, and the tube 11a may communicate with the suction pump 14 while the valve is opened and closed, and the tube 11b may always communicate with the suction pump 14. That is, this valve serves as switching means, and switches between whether the suction pump 14 communicates with both the two tubes 11a and 11b or communicates only with the tube 11b by opening and closing the valve.

  In this embodiment, the single suction pump 14 performs both the suction of the internal space of the cap 60 and the suction of the bottom wall 69 to the cap holder 63. However, separate suction pumps may be provided. Good. In this case, the switching unit 15 may not be provided.

  Further, in the present embodiment, the cap chips 67 and 68 are disposed in the recesses 61 and 62 of the cap 60, but the cap chips 67 and 68 may not be disposed.

  In addition, in this 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, but the side wall 70 is not standing, A lip projecting directly from the bottom wall may form a recess for receiving ink.

  Further, in the present embodiment, the holding 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 drives the holding member 80 up and down. The cap 60 is moved up and down, but the cap holder 63 and the holding member 80 may not be provided. In that 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, the cap 60 is preferably formed of an elastic member such as rubber for the lip 76 that contacts the ink discharge surface 38, but the bottom wall 69 is not particularly required to be an elastic member, and a resin plate, a metal plate, or the like. It may be.

  In this embodiment, the cap 60 is fitted and supported by the concave cap holder 63. However, the support member that supports the cap 60 is simply a plate-like member that contacts the lower surface 69c of the cap 60. It may be a tip such as a tube connected to the suction pump 14 that contacts the lower surface 69 c of the cap 60.

  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 an 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 the BB sectional view taken on the line of FIG. 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.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Printer 3 Inkjet head 13 Suction cap apparatus 14 Suction pump 15 Switching unit 38 Ink discharge surface 40 Nozzle 60 Cap 69 Bottom wall 70 Side wall 76, 79 Lip

Claims (7)

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 suction means that communicates with the internal space of the cap member and sucks the internal space;
A support member that supports the bottom wall portion of the cap member;
A suction means for sucking the bottom wall portion to the support member when a suction operation is performed by the suction means in a capping state in which the tip of the lip is in close contact with the liquid discharge surface. A suction cap device.   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 bottom wall is formed in a flat plate shape,
The support member has a planar support surface that contacts a contact surface opposite to a surface of the bottom wall portion that faces the liquid discharge surface,
The suction cap device according to claim 1, wherein the suction unit causes the entire contact surface of the bottom wall portion to be sucked to the support surface of the support member. The support member is formed with a suction hole that opens toward the bottom wall,
The suction means is connected to the other end of the suction hole opposite to the one end on the bottom wall portion side, and sucks a space between the bottom wall portion and the support member through the suction hole. The suction cap device according to claim 1, wherein the bottom wall portion is adsorbed to the support member.   The suction cap device according to claim 4, wherein the suction means also serves as the suction means for sucking the bottom wall portion to the support member through the suction hole of the support member. Switching means for switching whether the suction means communicates only with the internal space of the cap member or communicates with both the internal space and the space between the bottom wall portion and the support member;
A capping position where the tip of the lip is in a capping state where the tip of the lip is in close contact with the liquid ejection surface, and a moving mechanism for moving the cap member over a retreat position retracted from the capping position,
The switching means is
When the cap member is positioned at the retracted position by the moving mechanism, the suction means is communicated only with the internal space,
When the cap member is positioned at the capping position by the moving mechanism, the suction means is communicated with both the internal space and the space between the bottom wall portion and the support member. Item 6. The suction cap device according to Item 5. The suction cap device according to claim 1, wherein a cap chip is accommodated in the internal space of the cap member.

Images