Abstract:
A printer maintenance apparatus, includes: a mounting base movable forward and backward between a maintenance position and a retraction position; a wiping mechanism mounted on the mounting base and including a wiper base and a wiper; and a capping mechanism mounted on the mounting base including a cap base and a cap. The cap base moves toward the nozzle surface to move the cap to cover the nozzle surface when the mounting base is at the maintenance position. The cap base moves retractably from the nozzle surface when the mounting base moves from the maintenance position. The wiper base moves toward the nozzle surface to bring the wiper into contact with the nozzle surface when the mounting base is at the maintenance position. The wiper base keeps the wiper in contact with the nozzle surface while the mounting base moves backward from the maintenance position.

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to a printer maintenance apparatus for wiping and capping the nozzle surface of a print head for ejecting ink droplets from a plurality of nozzles for printing. 
   2. Background Art 
   In the related art, as disclosed in JP-A-2002-120386, a recovery processing unit body of a printer mounted with a cap or a wiper is inserted to the Lower side of a print head so as to perform wiping or capping the nozzle surface. 
   At that time, a guide pin provided in the recovery processing unit body is engaged with a cam groove formed in a guide plate. Thus, in accordance with the shape of the cam groove, the recovery processing unit body is inserted to the lower side of the print head while the recovery processing unit body is moved up toward the nozzle surface so as to perform wiping or capping. 
   SUMMARY OF THE INVENTION 
   In such a related-art method, however, the recovery processing unit body is moved up toward the nozzle surface to thereby bring the wiper into contact with the nozzle surface halfway during the process of inserting the recovery processing unit body to the lower side of the print head in accordance with the shape of the cam groove. Then, the recovery processing unit body is further inserted to the lower side of the print head so as to clean the nozzle surface with the wiper. After that, the nozzle surface is covered with the cap, and recovery operation to eject ink from nozzles is performed. 
   Then, the recovery processing unit body is retreated from the lower side of the print head in the state where the recovery processing unit body has been moved down to leave the nozzle surface. Accordingly, after the recovery operation is performed, the recovery processing unit body is retreated directly without cleaning the nozzle surface with the wiper. Ink and the like may adhere to the nozzle surface during the recovery operation. It is therefore preferable to clean the nozzle surface immediately after the recovery operation. However, since both the forward/backward motion and the up/down motion of the recovery processing unit body depend on the cam groove, there is a problem that the structure of the cam groove is so complicated that the degree of freedom during operation is low. When the wiper or the cap is intended to move up/down independently of the recovery processing unit body in order to increase the degree of freedom, another drive source such as a solenoid is required. Thus, there is a problem that the unit becomes complicated. 
   A printer maintenance apparatus is disclosed herein, which can carry out wiping or capping at proper timing with a simple structure. 
   The invention may provide a printer maintenance apparatus for maintaining a printer having a print head, wherein the print head includes a nozzle surface in which a plurality of nozzles are formed, for ejecting ink droplets onto fed printing medium for printing. The apparatus includes: a mounting base that is movable forward and backward between a maintenance position and a retraction position, the maintenance position in which the mounting base is opposed to the nozzle surface and the retraction position in which the mounting base is retracted from the print head; a wiping mechanism being mounted on the mounting base and including a wiper base supported on the mounting base movably toward the nozzle surface and a wiper attached to the wiper base; and a capping mechanism being mounted on the mounting base and including a cap base supported on the mounting base movably toward the nozzle surface and a cap attached to the cap base. The cap base moves toward the nozzle surface to move the cap to cover the nozzle surface when the mounting base is at the maintenance position. The cap base moves retractably from the nozzle surface when the mounting base moves from the maintenance position toward the retraction position. The wiper base moves toward the nozzle surface to bring the wiper into contact with the nozzle surface when the mounting base is at the maintenance position. The wiper base keeps the wiper in contact with the nozzle surface while the mounting base moves backward from the maintenance position toward the retraction position. 
   The invention may provide a printer including: a print head including a nozzle surface that ejects ink droplets onto fed printing medium; a mounting base that is movable forward and backward between a maintenance position and a retraction position, the maintenance position in which the mounting base is opposed to the nozzle surface and the retraction position in which the mounting base is retracted from the print head; a wiping mechanism being mounted on the mounting base and including a wiper base supported on the mounting base movably toward the nozzle surface and a wiper attached to the wiper base; and a capping mechanism being mounted on the mounting base and including a cap base supported on the mounting base movably toward the nozzle surface and a cap attached to the cap base; wherein the cap base moves toward the nozzle surface to move the cap to cover the nozzle surface when the mounting base is at the maintenance position; the cap base moves retractably from the nozzle surface when the mounting base moves from the maintenance position toward the retraction position; the wiper base moves toward the nozzle surface to bring the wiper into contact with the nozzle surface when the mounting base is at the maintenance position; and the wiper base keeps the wiper in contact with the nozzle surface while the mounting base moves backward from the maintenance position toward the retraction position. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The present invention may be more readily described with reference to the accompanying drawings: 
       FIG. 1  is a configuration diagram of a printer using maintenance apparatus according to an embodiment of the invention, in which a mounting base is in a maintenance position. 
       FIG. 2  is a configuration diagram of the printer using the maintenance apparatus according to the embodiment, in which the mounting base is in a retraction position. 
       FIG. 3  is a plan view of the mounting base mounted with a capping mechanism and a wiping mechanism according to the embodiment. 
       FIG. 4  is a sectional view of the mounting base mounted with a capping mechanism and a wiping mechanism according to the embodiment, in which the mounting base is in the maintenance position. 
       FIG. 5  is a sectional view of the mounting base mounted with the capping mechanism and the wiping mechanism according to the embodiment, in which the mounting base is in the retraction position. 
       FIGS. 6A to 6C  are explanatory views for explaining the operation of the wiping mechanism at a forward end according to the embodiment. 
       FIGS. 7A to 7C  are explanatory views for explaining the operation of the wiping mechanism at a backward end according to the embodiment. 
       FIGS. 8A and 8B  are explanatory, partially sectional views showing a mounting base mounting with a capping mechanism according to another embodiment. 
       FIGS. 9A and 9B  are explanatory views for explaining the operation of a wiping mechanism at forward and backward ends according to another embodiment. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   Embodiments of the invention will be described below in detail with reference to the drawings. 
   As shown in  FIGS. 1 and 2 , a printer according to this embodiment has a full-line type print head  1 , and a large number of not-shown nozzles are arrayed in the print head  1  in a direction perpendicular to the direction of feeding printing paper. A nozzle surface  2  in which the nozzles are opened is disposed to be opposed to the printing paper. 
   In addition, the print head  1  is of an ink jet system for ejecting ink droplets onto the printing paper. For example, such a print head  1  is provided for respective colors of yellow, magenta, cyan and black. Incidentally, each part of the print head  1  is supplied with its corresponding color ink from an ink cartridge  4  through an ink supply mechanism  6 . 
   The printing paper is fed in tight contact with the surface of a belt  10  laid between a pair of rollers  8  (only one of which is shown). Each print head  1  is disposed in a body case  11  movably in a direction perpendicular to the surface of the belt  10  on which the paper is mounted. At the time of carrying out printing, the print head  1  is moved to an ink ejection position close to the printing paper as shown in  FIG. 2 . At the time of maintenance, the print head  1  is moved to a standby position in which a predetermined space is formed between the print head  1  and the printing paper and which is more distant from the belt  10  than the ink ejection position, as shown in  FIG. 1 . 
   A mounting base  12  which can be inserted into this space is provided. As shown in  FIG. 3 , the mounting base  12  is supported on a pair of guide bars  14  and  16  through a plurality of sliding members  18  so that the mounting base  12  can move forward/backward linearly. The guide bars  14  and  16  are disposed perpendicularly to the direction of feeding the printing paper (direction perpendicular to the paper surface of  FIG. 1 ). A belt  19  is laid in parallel with the guide bars  14  and  16 . The mounting base  12  and the belt  19  are fastened to each other through a lock member  20 . 
   When the belt  19  is driven by a motor, the mounting base  12  slides along the guide bars  14  and  16  so that the mounting base  12  can move forward/backward between a maintenance position (position designated by the solid line in  FIG. 1 ) in which the mounting base  12  is inserted into the space between the print headland the printing paper and a retraction position (position designated by the chain double-dashed line in  FIG. 1  and position illustrated in  FIG. 2 ) in which the mounting base  12  is retracted from the space to the upper side of the ink cartridge  4  at the time of printing. 
   A capping mechanism  22  is mounted on the mounting base  12 . The capping mechanism  22  has a plurality of links  24  one ends of which are supported swingably on the mounting base  12 , and a cap base  26  on which the other ends of the links  24  are supported swingably. The cap base  26  is designed to swing due to its own weight in a direction in which the mounting base  12  moves forward to the maintenance position, so as to leave the nozzle surface  2  and come into contact with the mounting base  12 , as shown in  FIGS. 4 and 5 . Incidentally, the cap base  26  may be designed to leave the nozzle surface  2  by means of an urging member instead of its own weight. 
   On the cap base  26 , each engagement portion  28  integrated with the cap base  26  is formed to protrude toward the nozzle surface  2 . On the print head  1 , each lock member  29  as a fixed side is formed to protrude from the nozzle surface  2 . When the mounting base  12  is moved forward to the maintenance position, the engagement portion  28  abuts against the lock portion  29  near the forward end to thereby move the cap base  26  toward the nozzle surface  2  so as to describe an arc while keeping the cap base  26  parallel with the nozzle surface  2 . 
   On the cap base  26 , a swinging base  30  is supported swingably around a pin  32 . Coil springs  33   a  and  33   b  are disposed on the opposite sides of the pin  32  and between the cap base  26  and the swinging base  30 . Correspondingly to the respective colors of the print head  1 , in this embodiment, four caps  34  are attached to the swinging base  30 . Each cap  34  is made of an elastically deformable material, and particularly formed out of a material resistant against ink, such as butyl rubber or EPDM. 
   A bottom surface  36  opposed to the nozzle surface  2  is formed in the cap  34  as shown in  FIG. 3 . The bottom surface  36  is substantially flat, and an exhaust hole  38  opened in the bottom surface  36  is formed in the cap  34 . The exhaust hole  38  is designed to be connected to a not-shown exhaust duct so as to be able to exhaust ink. In the cap  34 , a lip piece  40  is provided to surround the bottom surface  36 . The lip piece  40  protrudes toward the nozzle surface  2  of the print head  1 . 
   A wiping mechanism  42  is also mounted on the mounting base  12 . As shown in  FIGS. 6A-6C , the wiping mechanism  42  has a wiper base  46  supported on the mounting base  12  swingably around a fulcrum pin  44 . The wiper base  46  has a support portion  46   a  provided erectly toward the nozzle surface  2 . A wiper  48  is attached to the support portion  46   a . In addition, an urging member  50  using a coil spring is disposed between the wiper base  46  and the mounting base  12 , so as to swing the wiper base  46  around the fulcrum pin  44  and thereby urge the wiper  48  toward the nozzle surface  2 . 
   An abutment pin  52  is provided erectly on the wiper base  46 . As shown in  FIG. 4 , the abutment pin  52  is formed to be high enough to abut at its front end against the nozzle surface  2  to thereby regulate the swinging of the wiper base  46  when the wiper base  46  is swung. In such a state where the swinging of the wiper base  46  is regulated, the wiper  48  is brought into contact with the nozzle surface  2  by moderate force. 
   On the mounting base  12 , a lever  54  is supported swingably around a fulcrum pin  56 . The lever  54  is designed as follows. That is, when the lever  54  swings around the fulcrum pin  56 , the lever  54  abuts at its front end against the wiper base  46  so as to swing the wiper base  46  against the urging force of the urging member  50 , and thereby push down the wiper base  46  in a direction to leave the nozzle surface  2 , as shown in  FIG. 5 . 
   When the front end of the lever  54  abuts against the support portion  46   a , the lever  54  is located beyond a line passing through the center of the fulcrum pin  56  and perpendicular to the nozzle surface  2 , and on the opposite side with respect to the line (the left side in  FIGS. 6A-6C  with respect to the line). However, the further swinging is regulated because the lever  54  abuts against the support portion  46   a.    
   The fulcrum pin  56  protrudes outside the mounting base  12 . A swinging arm  58   a  is integrally attached to the fulcrum pin  56 . A pin  58   b  parallel with the fulcrum pin  56  is provided erectly on the swinging arm  58   a . To the body case  11 , a forward-side protrusion  59   a  is attached as a fixed side with which the pin  58   b  comes into contact when the mounting base  12  reaches the forward end. 
   When the pin  58   b  abuts against the forward-side protrusion  59   a , the lever  54  is swung through the swinging arm  58   a  and the fulcrum pin  56 . Thus, the lever  54  is swung in a direction to leave the support portion  46   a  so as to be located beyond the perpendicular line and on the opposite side with respect to the perpendicular line (the right side in  FIGS. 6A-6C  with respect to the perpendicular line). As shown in  FIG. 6C , the wiper base  46  is swung around the fulcrum pin  44  by the urging force of the urging member  50  so that the wiper  48  is swung to be located in the wiping position where the wiper  48  is brought into contact with the nozzle surface  2 . Incidentally, in this embodiment, when the wiper  48  is located in the wiping position, the swinging arm  58   a  abuts against a stopper  57  so as to prevent the wiper  48  from swinging further. 
   In addition, to the body case  11 , a backward-side protrusion  59   b  is attached as a fixed side with which the pin  58   b  comes into contact at the backward end when the mounting base  12  is moved backward to the retraction position. The backward-side protrusion  59   b  is designed as follows. That is, when the mounting base  12  moves to the backward end, the pin  58   b  abuts against the backward-side protrusion  59   b  so as to swing the lever  54  through the swinging arm  58   a  and the fulcrum pin  56 . Thus, the lever  54  is swung in a direction to contact with the support portion  46   a  so as to be located beyond the perpendicular line and on the opposite side with respect to the perpendicular line. As a result, the wiper base  46  is swung to swing the wiper  48  to the separation position where the wiper  48  has left the nozzle surface  2 , as shown in  FIG. 7C . 
   Next, description will be made on the operation of the printer maintenance apparatus according to this embodiment. 
   At the time of printing, the belt  10  is driven by the rotations of the rollers  8  so that printing paper passes under the print head  1  at a fixed speed. Then, ink droplets are ejected from the print head  1  so that printing is performed line by line. 
   At the time of maintenance for recovering the nozzles of the print head  1  from clogging or for cleaning the nozzles of the print head  1 , the print head  1  is moved from the ink ejection position shown in  FIG. 2  to the standby position shown in  FIG. 1 , in a direction to leave the printing paper, by a head vertical motion motor. Thus, a predetermined space is formed. Then, driven by the belt  19 , the mounting base  12  is guided along the guide bars  14  and  16  and moved from the retraction position to the maintenance position where the mounting base  12  is inserted into the space under the print head  1 . 
   At the time of forward motion in which the mounting base  12  moves from the retraction position to the maintenance position, when the mounting base  12  reaches the vicinity of the forward end, each engagement portion  28  abuts against each lock portion  29 . Further, when the mounting base  12  reaches the forward end, the plurality of links  24  swing to move the cap base  26  toward the nozzle surface  2  so as to describe an arc while retaining the cap base  26  parallel with the nozzle surface  2 . 
   As a result, the cap  34  is pressed onto the nozzle surface  2 . In that event, the swinging base  30  equalizes the cap  34  around the pin  32  so as to press the cap  34  onto the nozzle surface  2  with uniform pressing force. In the state where each engagement portion  28  is brought into abutment against each lock portion  29 , the state where the nozzle surface  2  is covered with the cap  34  is retained. 
   On the other hand, similarly, at the time of forward motion in which the mounting base  12  moves from the retraction position to the maintenance position, when the mounting base  12  reaches the vicinity of the forward end, the pin  58   b  abuts against the forward-side protrusion  59   a  so as to swing the lever  54  through the swinging arm  58   a  and the fulcrum pin  56  as shown in  FIG. 6A . When the mounting base  12  is further moved toward the forward end, the lever  54  swings in a direction to leave the support portion  46   a  so as to be located beyond the perpendicular line and on the opposite side with respect to the perpendicular line as shown in  FIG. 6B . When the mounting base  12  reaches the forward end, the wiper base  46  is swung around the fulcrum pin  44  by the urging force of the urging member  50  as shown in  FIG. 6C . Thus, the wiper  48  is moved to the wiping position where the wiper  48  is brought into contact with the nozzle surface  2 . 
   Then, ink droplets are ejected from the nozzles so as to solve clogging or the like. Thus, recovery processing is performed. When printing is to be performed after the recovery processing is terminated, the mounting base  12  is moved backward from the maintenance position to the retraction position. When the mounting base  12  leaves the maintenance position, the pin  58   b  leaves the forward-side protrusion  59   a . However, the wiper base  46  is urged by the urging member  50  so as to be located in the position where the wiper base  46  is regulated by the stopper  57 . Thus, the front end of the wiper  48  keeps contacting with the nozzle surface  2 . Under such a condition, the wiper  48  moves toward the retraction position while wiping and cleaning the nozzle surface  2 . Incidentally, once the recovery processing (purge) is performed, the mounting base  12  is preferably retracted from the maintenance position immediately after the purge so as to perform cleaning with the wiper  48 . It is because the recovery performance would be lower if the time for ink to adhere to the nozzle surface  2  were longer. 
   In addition, when the mounting base  12  moves backward from the maintenance position, the engagement portion  28  leaves the lock portion  29 . As a result, the plurality of links  24  swing to allow the cap base  26  to fall due to its own weight. Thus, the cap  34  leaves the nozzle surface  2 , and the cap base  26  comes into contact with the mounting base  12  as shown in  FIG. 5 . Although the cap base  26  falls due to its own weight here, the cap base  26  may be urged in a direction to leave the nozzle surface  2  by an urging member such as a tension spring provided between the cap base  26  and the mounting base  12 . Thus, the cap base  26  can be moved down surely. 
   When the wiper  48  cleans the nozzle surface  2  and the mounting base  12  reaches the vicinity of the backward end, the pin  58   b  comes into contact with the backward-side protrusion  59   b  as shown in  FIG. 7A . When the mounting base  12  is further moved toward the backward end, the lever  54  is swung against the urging force of the urging member  50  through the swinging arm  58   a  and the fulcrum pin  56 . Thus, the lever  54  is swung in a direction to come into contact with the support portion  46   a  so as to be located beyond the perpendicular line and on the opposite side with respect to the perpendicular line as shown in  FIG. 7B . As soon as the lever  54  goes beyond the perpendicular line, the wiper base  46  is urged by the urging force of the urging member  50  in a direction to protrude the wiper  48  again. However, a pin  541  at the front end of the lever  54  contacts with the support portion  46   a  so that the posture of the lever  54  is retained at that position. That is, when the mounting base  12  reaches the backward end, the wiper base  46  swings to swing the wiper  48  to the separation position where the wiper  48  is located at a distance from the nozzle surface  2 , as shown in  FIG. 7C . The wiper base  46  is retained in the separation position till the pin  58   b  leaves the backward-side protrusion  59   b  and is released by the forward-side protrusion  59   a . In the retraction position where the mounting base  12  reaches the backward end, each of the wiper  48  and the cap  34  is at a lower level than the nozzle surface  2  as shown in  FIG. 5 . 
   In such a manner, the mounting base  12  performs forward/backward motion between the maintenance position and the retraction position so that the cap  34  and the wiper  48  are moved toward the nozzle surface  2  independently of each other. Then, by the forward motion of the mounting base  12 , the cap  34  is pressed onto the nozzle surface  2 , and the wiper  48  is brought into contact with the nozzle surface  2 . Thus, capping and wiping can be attained with a simple structure. In addition, the nozzle surface  2  is cleaned with the wiper  48  during the backward motion of the mounting base  12  after recovery processing is performed with the nozzle surface  2  being covered with the cap  34 . Therefore, ink and the like adhering to the nozzle surface  2  during the recovery processing can be cleaned up. Thus, wiping and capping can be performed at proper timing. 
   Next, description will be made on another capping mechanism  60  different from the aforementioned capping mechanism  22 , with reference to  FIGS. 8A and 8B . Incidentally, members the same as those in the aforementioned embodiment are denoted by the same reference numerals correspondingly, and their detailed description will be omitted. The same thing can be applied to the following drawings. 
   In this capping mechanism  60 , cam grooves  62   a  and  62   b  are formed in the mounting base  12 . Pins  64   a  and  64   b  attached to the cap base  26  are inserted to the cam grooves  62   a  and  62   b  so that the pins  64   a  and  64   b  can slide along the cam grooves  62   a  and  62   b . The cam grooves  62   a  and  62   b  are formed to be inclined obliquely with respect to the direction of the forward/backward motion of the mounting base  12 . 
   In addition, an urging member  66  using a coil spring is provided between the mounting base  12  and the cap base  26 . As shown in  FIG. 8A , the cap base  26  is moved along the cam grooves  62   a  and  62   b  by the pulling urge of the urging member  66 , so as to allow the cap  34  to leave the nozzle surface  2 . Then, when the mounting base  12  is moved forward and the engagement portion  28  abuts against the lock portion  29 , the cap base  26  is moved toward the nozzle surface  2  against the urging force of the urging member  66 , so as to press the cap  34  onto the nozzle surface  2 . This embodiment using the capping mechanism  60  can be also carried out in the same manner as in the aforementioned embodiment. 
   Next, description will be made on another wiping mechanism  70  different from the wiping mechanism  42 , with reference to  FIGS. 9A and 9B . 
   In this wiping mechanism  70 , as shown in  FIG. 9A , an inclined cam  72  is inserted to the lower side of the wiper base  46  so as to swing the wiper base  46  toward the nozzle surface  2 . The inclined cam  72  is supported slidably on the mounting base  12 . When the mounting base  12  reaches the forward end, the inclined cam  72  abuts against the body case  11  and is inserted to the lower side of the wiper base  46  so as to swing the wiper  48  to the wiping position, as shown in  FIG. 9B . 
   On the other hand, when the mounting base  12  reaches the backward end, the inclined cam  72  abuts against a not-shown protrusion formed on the body case  11  so as to be extracted from the wiper base  46 . Thus, when the mounting base  12  reaches the backward end, the wiper  48  is swung to the retraction position as shown in  FIG. 9A . This embodiment using the wiping mechanism  70  can be also carried out in the same manner as in the aforementioned embodiment. 
   The invention is not limited to such embodiments at all, but it can be carried out in various forms without departing from the spirit and scope of the invention. 
   As described above in detail, in printer maintenance apparatus according to the embodiments, the mounting base  12  moves forward/backward between a maintenance position and a retraction position so that the cap  34  and the wiper  48  are moved toward the nozzle surface  2  independently of each other. By the forward motion of the mounting base  12 , the cap  34  is pressed onto the nozzle surface  2 , and the wiper  48  is brought into contact with the nozzle surface  2 . Thus, capping and wiping can be attained with a simple structure. On the other hand, when the mounting base  12  is moved backward after recovery processing is performed, the nozzle surface  2  is cleaned with the wiper. Thus, ink and the like adhering to the nozzle surface  2  during the recovery processing can be cleaned up. Accordingly, there is an advantage that wiping and capping can be performed at proper timing. 
   While the invention has been described in conjunction with the specific embodiments described above, many equivalent alternatives, modifications and variations may become apparent to those skilled in the art when given this disclosure. Accordingly, the exemplary embodiments of the invention as set forth above are considered to be illustrative and not limiting. Various changes to the described embodiments may be made without departing from the spirit and scope of the invention.