Patent Application
20050024425
This application claims priority from Japanese Patent Application No. 2003-203705 filed Jul. 30, 2004, which is hereby incorporated by reference.
1. Field of the Invention
The present invention relates to an ink-jet recording apparatus which performs recording by ejecting ink from recording means mounted on a carriage to a material to be recorded, particularly to the inkjet recording apparatus which is provided with a wiping means for wiping a nozzle surface of the recording means clean.
2. Related Background Art
In the inkjet recording apparatus, because the recording is performed by ejecting the ink from a micro nozzle toward the material to be recorded, the unnecessary ink is easy to adhere to the nozzle surface, and sometimes normal ink ejection is obstructed by the adhesion ink. Therefore, in the inkjet recording apparatus, a wiping means including a wiper blade for wiping the nozzle surface clean is provided, and the adhesion ink near the nozzle is wiped and removed in such a manner that the wiper blade and the nozzle surface are relatively moved while overlapped with each other.
A mode of the relative movement between the wiper blade and the nozzle surface includes the case in which a carriage mounting a recording head is moved with respect to the stationary wiper blade and the case in which the carriage mounting the recording head is caused to stand still to move the wiper blade in parallel with the carriage or to rotationally move the wiper blade. In most cases of the movement of the carriage, the movement of an extension of the recording movement of the carriage in a main scanning direction is utilized. In this case, the wiping is performed only when needed by taking the wiper blade in and out between an overlap position with respect to a moving path of the carriage (nozzle surface) and a retracting position. However, in the conventional configuration, it is necessary to sufficiently make a movable range of the carriage larger than a recording area, which leads to upsizing of the recording apparatus.
Recently, the nozzle surface of the recording head is often formed in a complicated concave and convex surface, so that it is harder than ever to sufficiently clean and remove dirt near the nozzle only by the wiping in the carriage movement direction in the use of the movement of the carriage. For the above-described reasons, the configuration in which the carriage is caused to stand sill to move the wiper blade is often used. In the case of the movement of the wiper blade, the wiper blade is reciprocated by the parallel movement or by the rotational movement in the direction intersecting (for example, orthogonally) the direction of the main scanning movement for the recording. In this case, the carriage is stopped at a wiping position, and the wiper blade is driven to wipe the nozzle surface of the recording head clean.
However, in the above-described wiping mean adopting the method of moving the wiper blade, in order to accurately wipe out a periphery of the nozzle of the recording head, it is required to stop the carriage mounting the recording head at the accurate position. Further, in order to prevent vibration during the movement of the carriage, recently a vibration dumping member is often attached between a motor used as a driving source of the carriage and the driven carriage. However, in the configuration in which the vibration dumping member is attached, due to elastic displacement in a driving mechanism, it becomes more difficult that the carriage is accurately stopped and the positioning of the carriage becomes more difficult and more inaccurate when the carriage is stopped.
It is an object of the invention to provide an inkjet recording apparatus in which the carriage can be stopped automatically and accurately at the wiping position and the wiping and cleaning of the nozzle surface of the recording means are accurately performed independently of the accuracy of the carriage stop action.
It is another object of the invention to provide an inkjet recording apparatus including a carriage which is reciprocated while mounting recording means for performing recording by ejecting ink to a material to be recorded, a position control member which defines a movement range of the carriage in such a manner that the carriage abuts on the position control member, and wiping means for wiping a nozzle surface of the recording means clean, wherein the wiping means wipes the nozzle surface clean while the carriage is abutted on the position control member.
Referring to the accompanying drawings, preferred embodiments of the invention will be specifically described below. In the following drawings, the same reference numeral shows the same component or the equivalent component.
In the inkjet recording apparatus 1, the recording is performed to the material to be recorded in a manner that the recording head 3 is driven on the basis of an image signal with the movement of the carriage 2 (main scanning) kept being controlled, while by conveying the material to be recorded (sub-scanning) supplied from the paper feeding mechanism 5 such as the recording paper and the like. The recording head 3 and ink cartridges 6 are detachably mounted on the carriage 5. The ink stored in the ink cartridge 6 is supplied to the recording head 3. In this case, both contact surfaces of the carriage 2 and of the recording head 3 come in proper contact with each other to realize necessary electrical connection.
The recording head 3 performs the recording in such a manner that pulse voltage corresponding to a recording signal is applied to the recording head 3 to selectively eject an ink droplet from a plurality of nozzles. The recording head 3 ejects the ink droplet from the nozzle by utilizing a change in pressure caused by growth and shrinkage of a bubble in film boiling created by thermal energy applied by an electrothermal energy conversion material. The electrothermal energy conversion material is individually provided in the plurality of nozzles. When the pulse voltage is applied to the corresponding electrothermal energy conversion material in accordance with the recording signal, the ink droplet is ejected from the nozzle corresponding to the electrothermal energy conversion material.
In
A linear encoder (not shown) is mounted inside the carriage 2. The linear encoder reads the bar on the code strip 8, thereby the position of the carriage 2 can be accurately detected even if the inkjet recording apparatus 1 is in a recording action. When output of the signal is not changed even if the drive motor M1 is driven for a predetermined time interval, it can be detected that the carriage 2 can be moved only up to the position, i.e. it can be detected that the movement of the carriage 2 is restricted (stopped) at the position. In an initializing action of the recording apparatus 1, the carriage 2 is moved toward the internal surface on right side of the chassis 9 in
In
The reference numeral 17 designates a conveying roller gear fixed to one end of the conveying roller 14. The conveying roller 14 is driven by transferring driving force of the drive motor M2 to the conveying roller gear 17. The material to be recorded in which the recording has been performed is discharged outside the inkjet recording apparatus 1 by a discharge roller 19. The discharge roller 19 is driven by transferring the driving force of the drive motor M2 to a discharge roller gear (not shown). The reference numeral 21 designates a spur roller which causes the recording sheet to be pressed against the discharge roller 19 by a spring (not shown), and the reference numeral 22 designates a spur holder which rotatably supports the spur roller 21.
A recovery device 10 which maintains and recovers ink ejection performance of the recording head 3 is disposed within the movement range of the carriage 2 and at a predetermined position outside the recording area. The recovery device 10 includes capping means 11 for covering the nozzles of the recording head 3, wiping means 12 for wiping a nozzle surface 23 of the recording head 3 clean, blade cleaning means 18 for cleaning a wiper blade of the wiping means 12, and sucking means 48 having a suction pump connected to the capping means 11 (
In FIGS. 1 to 4, the suction recovery processing can be performed by driving the sucking means 48 while the nozzles are sealed by the capping means 11. In the suction recovery processing, the ink is sucked and ejected forcibly from the nozzles to refresh the ink in the nozzles. That is, the ink whose viscosity is increased, the bubble, and the like are ejected with the ink from the nozzles by the suction recovery processing, which allows the ink ejection performance of the recording head 3 to be maintained and recovered. By capping the recording head 3 with the capping means 11 during non-recording, the drying of the ink in the nozzles can be prevented while the recording head 3 can be protected.
The capping action of the recording head 3 by the capping means 11 is performed at the capping position which is separated by several millimeters away from the home position of the carriage 2. Therefore, the suction recovery processing of the recording head 3 is also performed at the capping position. The reason why the suction recovery processing is performed at the capping position is as follows. Since the capping means 11 also has a function as a pre-ejection drain tray for receiving the ink ejected by the pre-ejection action in the recording frequently, the carriage 2 often abuts on the carriage position control member (abutting portion such as the chassis 9) in the recording action when the capping position corresponds to the home position, which easily results in a decrease in durability or generation of noise.
The wiping means 12 is used for wiping the nozzle surface 23 of the recording head 3 to remove the ink droplets and paper dust which adhere to the nozzle surface 23. The wiping means 12 is disposed near the capping means 11. In the embodiment, when the wiping means 12 wipes the nozzle surface 23 clean, the carriage 2 mounting the recording head 3 is maintained in the state in which the carriage 2 abuts on the carriage position control member 55 formed on the internal surface on the right side of the chassis 9 (in the state in which the carriage 2 is positioned at the home position in the embodiment). At this point, in order to securely perform the positional control of the carriage 2, the carriage drive motor M1 is continuously driven in the direction in which the carriage 2 is pressed against the position control member 55. However, in some cases, the driving of the carriage drive motor M1 can be also stopped during the wiping action after the positioning.
When the nozzle surface 23 of the recording head 3 is wiped clean by a wiper blade 41 (
In FIGS. 2 to 4, a tube pump (sucking means) 48 includes two suction tubes 32 and a pressing roller (not shown). The two suction tubes 32 are disposed along the internal surface of an arc portion of a recovery base 20, and the suction tubes 32 use the inside surface of the arc portion as a guide surface. The pressing roller generates negative pressure in the suction tube 32 in such a manner that the pressing roller is rotated so as to squeeze the suction tubes 32 while pressed against the suction tubes 32. The pressing roller is pressed against the suction tubes 32 by a pressing spring (not shown).
The pressing roller is pivotally supported to a pressing roller holder 31 being movable along a long hole-shaped groove formed in the pressing roller holder 31. The pressing roller is biased toward the side on which the suction tube 32 is pressed during the sucking action, and the pressing roller can be retracted from the suction tube 32 except for the case of the sucking action. In the embodiment, two pressing rollers are disposed for one suction tube 32, and four pressing rollers are disposed in total. The pressing roller holder 31 supporting pivotally the pressing rollers is supported pivotally to a pressing roller holder guide 30 while being rotatable in the radial direction of the arc guide surface of the recovery base 20. The pressing roller holder 31 presses the pressing roller against the suction tube 32 and retracts the pressing roller from the pressing roller holder 31. The pressing roller holder guide 30 has shafts at both ends, and is supported pivotally to the same shaft as the arc center of the arc guide surface on which the suction tube 32 of the recovery base 20 is installed additionally. The pressing roller holder guide 30 is rotatably arranged so as to transfer the driving force from a drive motor M3 (hereinafter referred to as PG motor) of the recovery device 10.
The driving force from the PG motor M3 to the sucking means 48 is transferred to a PG gear 24 first and then transferred to a pump gear 27 supported pivotally to the rotating shaft of the pressing roller holder guide 30. The sucking means 48 which is directly connected to a drive shaft of the PG motor M3 performs the sucking action by the rotation of the PG motor M3 in one direction (normal rotation), and performs the operation to separate the pressing roller from the suction tube 32 by the rotation of the PG motor M3 in the reverse direction (reverse rotation). The capping means 11 includes a cap 35, a cap absorber, a cap holder 36, a cap base 34, and a capping means lift lever 37. The cap 35 abuts on the nozzle surface 23 of the recording head 3. The cap absorber absorbs and collects the ink ejected from the nozzles of the recording head 3. The cap holder 36 supports the cap 35 and is biased toward the direction in which the cap 35 is pressed against the nozzle surface 23 by a capping spring (not shown). The cap base 34 supports the cap spring which gives capping pressure to the cap holder 36 and supports the cap holder 36 being slidable in the up and down direction. The capping means lift lever 37 comprises an arm member which abuts the cap 35 on the nozzle surface 23 of the recording head 3 and separates the cap 35 from the nozzle surface 23.
The suction tube 32 of the sucking means 48 is connected to a joint portion provided in the cap holder 36 of the capping means 11. While the cap 35 abuts on the nozzle surface 23 of the recording head 3 (during the capping state), the negative pressure is given to the cap 35 by the sucking action of sucking means 48, which allows the ink to be sucked (ejected) from the nozzles of the recording head 3. In the lifting action to abut the capping means 11 on the recording head 3 (lifting action of the capping means lift lever 37), the driving force of the PG motor M3 is transferred to a one way clutch gear 28 fitted to a cam 38 through PG gears 25 and 26, and the cam 38 performs the lifting action of the capping means 11. The one way clutch gear 28 transfers the driving force from the PG motor M3 to the cam 38 when the one way clutch gear 28 is rotated in one direction, and the one way clutch gear 28 idles not to transfer the driving force to the cam 38 when the one way clutch gear 28 is rotated in the other direction.
In addition to the driving of the capping means 11, the cam 38 is also used for driving the wiping means 12 and for controlling the lifting action of a carriage lock lever 29. The carriage lock lever 29 acts as positioning means for controlling a relative position of the recording head 3 and the capping means 11 during the recovering action by the recovery device 10. The action of each recovering means such as the capping means 11 and the wiping means 12 is performed in such a manner that the rotational positioning of the cam 38 is performed by a cam position detection sensor flag provided in the cam 38 and a cam position detection sensor 40 provided in the recovery device 10, to control each recovering means on the basis of the rotational position of the cam 38.
As shown in
In
In the wiping means 12, the nozzle surface 23 of the recording head 3 is wiped by moving the wiper blade 41 toward the direction in which the wiper blade 41 invades (direction of the arrow F), and the wiper blade 41 is further moved toward the invasion direction to pass a blade cleaner 47 of the blade cleaning means 18 to clean contamination such as the ink adhering to the wiper blade 41 by the blade cleaner 47. Then, when the drive of the blade holder 42 in the direction of arrow F is stopped in accordance with the rotational movement of the cam 38, the wiper blade 41 passes through the blade cleaner 47 by a operation of the return spring (not shown) and is further moved toward the direction of the arrow B to return to the original position shown in
The blade cleaner 47 is mounted to the blade cleaner holder 46. When the wiper blade 41 is moved toward the invasion direction (direction of the arrow F) to pass the blade cleaner 47, the blade cleaner holder 46 is made to stand still at an interference position to maintain the scraping performance well so that the ink and the like which adhere to the wiper blade 41 are effectively wiped off. On the other hand, when the wiper blade 41 passes through the blade cleaner 47 toward a retracting direction (direction of the arrow B), ink fly-off is suppressed as much as possible by configuring the blade cleaner 47 displacable toward the retracting direction. That is, the blade cleaner 47 is supported pivotally to the blade cleaner holder 46, and the blade cleaner 47 is configured so as to be retracted by rotating the blade cleaner 47 about the support shaft of the rotation when the wiper blade 41 passes through the blade cleaner 47.
The plurality of recovering actions of the recovery device 10 of the inkjet recording apparatus according to the embodiment of the invention will be described referring to FIGS. 1 to 12. When the suction recovery action of the recording head 3 is performed by the recovery device 10, the sequence showing the flow chart of
In
After the carriage is moved to the capping position, capping action is performed in Step S203. That is, in order to perform the suction recovery action at the capping position, the PG motor M3 drives to rotate the cam 38 and the capping means 11 makes the cap 35 to abut on the nozzle surface 23, to seal the nozzles (Step S203). Then, the PG motor M3 is rotated in the direction of the sucking action, i.e. the PG motor M3 is rotated in the direction in which the driving force is transferred onto the side of the sucking means 48, and the suction recovery action for sucking a predetermined amount of ink is performed (Step S204). After the sucking action (Step S204) is performed to retract the capping means 11 from the recording head 3, the carriage 2 is moved to the home position to abut on the carriage position control member 55 (
While the carriage 2 is positioned and stopped by abutting on the carriage position control member 55, the wiping means 12 wipes the nozzle surface 23 (Step S206). That is, in Step S206, after the carriage 2 is moved toward the home position to abut on the carriage position control member 55 formed on the internal surface on the right side of the chassis 9 in
As shown in
The wiping action and the blade cleaning action in Step S206 will be described referring to
Then, the movement direction of the wiper blade 41 is reversed by driving the PG motor M3, the wiper blade 41 is moved toward the wiping means retracting direction (direction of the arrow B) to return to the original position, then the wiping action is finished. Until the movement of the wiper blade 41 toward the invasion direction (direction of the arrow F) is finished, the wiping action and the blade cleaning action are performed while the carriage 2 abuts on the carriage position control member 55 formed on the internal surface on the right side of the chassis 9 (
In the case where the wiping action is performed, in order to prevent the carriage 2 from coming into contact with the unnecessary point of the recording head 3 when the wiper blade 41 is moved toward the retracting direction (return direction, the direction of the arrow B), the carriage 2 is previously moved and stopped at the carriage retracting position until the wiper blade 41 returns to the original position. The carriage retracting position is located adjacent to the recovery device 10. For example, the carriage retracting position is set at a position P, distance L away from the suction recovery position (or the home position) selected directly above the recovery device 10 toward the inside of the main body of the apparatus (for example, about 60 mm away from the suction recovery position toward the opposite side of the reference side).
After the wiping action is finished, the carriage 2 (recording head 3) is moved to the suction recovery position to perform the pre-ejection for ejecting the color mixture ink which may have intruded into the nozzles of the recording head 3 during the sucking action and the wiping action. Since the pre-ejection is performed at the suction recovery position in the embodiment, the pre-ejection is performed in such a manner that the ink is ejected from the nozzle into the cap 35 with the cap opened. After the pre-ejection is finished, the waste ink which has accumulated in the cap 35 is drained by an idle suction action. The draining the ink by the idle suction is performed by driving the sucking means 48 driven by the PG motor M3 in the direction in which the suction recovery action is performed so that the waste ink in the cap 35 is sucked and drained through the suction tube 32 connected to the cap 35. The pre-ejection and idle suction action (Step S208 in
At the time when the suction recovery action or the pre-ejection and idle suction action is finished, because the sucking action performed by the sucking means (suction pump) 48 is released while the pressing roller is pressed against the suction tube 32, the pressing roller is rotated driven by the PG motor M3 in the direction in which the sucking action is released, and the action in which the pressing roller is separated from the suction tube 32 is performed (Step S304 in
The cap closing action in the embodiment will be described referring to
After the wiping action is performed, the idle suction action for draining the waste ink accumulated in the cap 35 by the pre-ejection and the like in the recording is performed (Step S105). The idle suction action is performed in the same manner as the idle suction action in the pre-ejection and idle suction action (Step S208). Then, in Step S106, while the sucking action is stopped by reversely rotating the PG motor M3, the wiper blade 41 is retracted and moved to return to the original position. That is, in order to release the pressing roller 33 from the suction tube 32 of the sucking means 48, the pressing releasing action of the pressing roller 33 is performed by the reverse rotation of the PG motor M3.
The carriage 2 is previously moved to the carriage retracting position P shown in
The pre-ejection and idle suction action in the recording (Step S300) in the embodiment will be described referring to
After the idle suction action (Step S303), the pressing releasing action of the pressing roller is performed by the reverse rotation of the PG motor M3, and the pressing roller is separated from the suction tube 32 of the sucking means 48 to be in the pressing releasing state (Step S304). Then the cap 35 is returned to the same position as the position immediately before performing the pre-ejection and idle suction action in the recording (Step S300), and the sequence of the pre-ejection and idle suction action is finished (Step S305).
As can be seen from the above descriptions, according to the embodiments of the invention, the inkjet recording apparatus in which the carriage can be stopped automatically and accurately at the wiping position and the wiping and cleaning of the nozzle surface of the recording means are accurately performed independently of the accuracy of the carriage stop action is provided.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2003-203705 | Jul 2003 | JP | national |
