The entire disclosure of Japanese Patent Application No. 2006-200400, filed Jul. 24, 2006 is expressly incorporated herein by reference.
1. Technical Field
The present invention relates to a liquid ejecting apparatus. More specifically, the present invention relates to a liquid ejecting apparatus capable of securely capping the liquid ejecting nozzles in a inexpensive and secure manner.
2. Related Art
One example of a liquid ejecting apparatuses which eject liquid onto a target is an ink jet recording apparatus which records print data onto a recording sheet by ejecting ink droplets from nozzles onto the recording sheet. In such apparatuses, however, many printing defects may occur, such as increased ink viscosity caused by evaporation of solvents from the openings of the nozzles, dust adhesion in the openings of the nozzles, and the mixing of bubbles in the ink caused by replacement of a cartridge, and the like.
In order to ensure that the nozzles are operating properly, a cap for capping the nozzle faces is typically used to cover the nozzle faces of the recording head when the apparatus is not printing. An ink absorber is placed inside the cap to keep the humidity inside the cap high during capping in order to prevent evaporation of the solvent through the nozzle openings, in an attempt to prevent the increase in the viscosity of ink.
In addition, an exhaust port is formed in the bottom surface of the cap to discharge ink or bubbles which is connected to a tube fixed to the cap. A suction pump is attached to the tube, and a negative pressure is applied to the inside of the cap by a suction operation of the suction pump. A cleaning operation is also performed by discharging any ink with an increased viscosity or bubbles caused by the replacement of the ink cartridge.
A cleaning device has been developed, which includes a plurality of recording heads and a plurality of caps covering the recording heads, wherein a suction operation may be performed individually or collectively on the recording heads. In such a cleaning device, a negative pressure supply switching unit is provided which selectively switches the supply of negative pressure to the caps. When the negative pressure supply switching unit selects a cap, the supply of negative pressure and the suction pump is driven, such that negative pressure is supplied to the cap connected to the suction pump, causing a suction operation to be performed on the recording head corresponding to the cap. With this arrangement, it is possible to selectively perform a suction operation on the caps.
One example of an apparatus which performs a suction operation on the caps is disclosed in Japanese Patent Application JP-A-2001-347689, which discloses an apparatus wherein the supply of negative pressure is selected by the phase control of a rotating cam. The rotating cam serves as a negative pressure supply switching unit that selectively presses and blocks the tubes in communication with the caps. Moreover, Japanese Patent Application JP-A-2004-358792 discloses an apparatus in which a cap is selected by a valve operation, and Japanese Patent Application JP-A-2005-329693 discloses an apparatus wherein the cap is selected by a cylindrical cam-based valve operation.
One difficulty in the apparatus in which the cap is selected using the phase control of the rotating cam, is that it is necessary to have a motor for driving the rotating cam as well as a sensor for detecting the phase of the rotating cam, meaning that the cost of the apparatus is increased. And in the apparatuses where the cap is selected by the valve operation, it is necessary to have a complex mechanism such as a valve in the ink flow path, which increases the likelihood of clogging when using pigment ink, which is undesirable in view of long term reliability.
An advantage of some aspects of the invention is that it provides a liquid ejecting apparatus capable of selecting a cap for suction in a secure manner and at low cost.
One aspect of the invention is a liquid ejecting apparatus comprising a liquid ejecting head capable of ejecting liquid from nozzles, a carriage capable of carrying the liquid ejecting head in a main scanning direction in a reciprocating manner, a plurality of cap spaces capable of capping nozzle faces so as to cover the nozzles of the liquid ejecting head, a suction pump capable of applying a negative pressure to each of the cap spaces so as to suck liquid from the nozzles, a plurality of suction channels which communicate with the plurality of cap spaces, so as to remove the liquid sucked by the suction pump, channel selection means for selecting one or more suction channels for cutting off the communication to the cap spaces based on the position of the carriage, and a communication cut-off means for cutting off the communication of the suction channels selected by the channel selecting means.
In the apparatus of the invention, the suction channels are selected on the basis of the position of the carriage, and the communication of the suction channels to the cap spaces is maintained or cut off based on the selection. By using this system, liquid is selectively sucked from the nozzles corresponding to the cap spaces. Thus, one aspect of the invention is the ability to select a cap space for liquid suction, based on the position of the carriage. Advantageously, since the suction channels are selected by the movement of the carriage carrying the recording head, unlike the known art, it is not necessary to have a rotating cam control means or sensor, meaning that it is possible to select the cap space for suction at low cost without complicating installation work. In addition, since the selection of suction channels is performed using the carriage, which is subject to highly precise positioning and/or movement control, it is possible to select the cap for suction in a secure manner. Therefore, it is possible to select the cap space for suction at low cost without complicating installation work.
The invention will be described with reference to the accompanying drawings, wherein like numbers reference like elements.
Hereinafter, a first embodiment of the invention will be described with reference to
As shown in
A waste liquid tank 14 containing used ink therein extends in the longitudinal direction (i.e., in the direction indicated by the arrow X in
A carriage motor 16 is fixed to the outer surface of the side wall on the rear side of the frame 12. The output shaft of the carriage motor 16 penetrates the side wall on the rear side of the frame 12, and a drive pulley 17 is fixed to the front end of the output shaft. A driven pulley 18 is rotatably supported on the inner surface of the side wall on the rear side of the frame 12 with a predetermined distance from the drive pulley 17 in the longitudinal direction of the frame 12. An endless belt 19 is stretched between the drive pulley 17 and the driven pulley 18. A carriage 20 that carries a recording head 24, described more fully below, is fixed to the belt 19 and is capable of moving in a main scanning direction in a reciprocating manner.
A guide member 21 extending parallel to the platen is provided between the opposing side walls of the frame 12. The guide member 21 is inserted through the carriage 20 so that the carriage 20 slides along the guide member 21. The drive pulley 17 rotates with the driving of the carriage motor 16. As a result, the carriage 20 reciprocates in the longitudinal direction (i.e., the main scanning direction that is the X-axis direction in
Two ink cartridges 22 and 23 are detachably mounted on the carriage 20. By way of example, the ink cartridge 22 contains black ink. In contrast, the inner space of the ink cartridge 23 is partitioned into three chambers containing magenta, cyan, and yellow.
As shown in
In the present embodiment, the first recording head 24a communicates with the ink cartridge 23 containing color ink and ejects the color ink, and the second recording head 24b communicates with the ink cartridge 22 containing black ink and ejects the black ink.
A non-printable area (a home position) is located in one side portion of the frame 12. A cap member 31 and a wiping member 32 are disposed in the non-printable area as means for cleaning the recording head 24.
The cap member 31 is provided with a plurality of cap spaces 25 that are opened upward and capable of capping the nozzle faces so as to cover the nozzles of the recording head 24. In the present embodiment, a first cap space 25a and a second cap space 25b are provided to correspond to the first recording head 24a and the second recording head 24b, respectively.
The cap member 31 is moved toward and away from the nozzle faces of the first and second recording heads 24a and 24b by cap lifting means (not shown). When the cap member 31 is moved upward, the upper end of the cap member 31 makes close contact with the nozzle faces of the first and second recording heads 24a and 24b. Then, the nozzles formed on the nozzle faces of the first recording head 24a are capped by the cap member 31, and the nozzles are sealed with the cap space 25a. Simultaneously, nozzles formed on the nozzle faces of the second recording head 24b are capped by the cap member 31, and the nozzles are sealed with the cap space 25b.
A suction pump 26 is further provided, which is capable of applying a negative pressure to each of the cap spaces 25a and 25b so as to suck ink from the nozzles of the recording head 24 that are capped. The first cap space 25a communicates with the suction pump 26 via a first tube member 27a, and the second cap space 25b communicates with the suction pump 26 via a second tube member 27b. Internal channels of the first tube member 27a and the second tube member 27b serve as a plurality of suction channels for communicating with the plurality of cap spaces 25a and 25b, respectively, so as to remove the liquid sucked by the suction pump 26.
When the suction pump 26 is in a state wherein the first and second recording heads 24a and 24b are capped by the cap member 31, negative pressure is applied to the first and second cap spaces 25a and 25b via the first and second tube members 27a and 27b, respectively. Using the negative pressure, ink is sucked from the nozzles of the first and second recording heads 24a and 24b. The ink then fills the first and second cap spaces 25a and 25b and flows toward the suction pump 26 through the first and second tube members 27a and 27b, respectively. Then, the ink is discharged into the waste liquid tank 14.
The recording apparatus includes a channel selection means for selecting one or more tube members for which the communication is to be cut off among the plurality of tube members serving as suction channels, based on the position of the carriage 20. The recording apparatus also includes a communication cut-off means for cutting off the communication of the one or more tube members selected by the channel selecting means.
More specifically, portions of the first and second tube members 27a and 27b are disposed above a first tube seat 28a and a second tube seat 28b, respectively.
A first lever member 29a is disposed above the first tube seat 28a on which a portion of the first tube member 27a is placed. When the first lever member 29a is operated, the first tube member 27a is compressed between the first tube seat 28a and the first lever member 29a, blocking the suction channel formed by the first tube member 27a.
Similarly, a second lever member 29b is disposed above the second tube seat 28b on which a portion of the second tube member 27b is placed. When the second lever member 29b is operated, the second tube member 27b is compressed between the second tube seat 28b and the second lever member 29b, blocking the suction channel formed by the second tube member 27b.
The carriage 20 is provided with a plate-like heteromorphic member 30 that reciprocates in the main scanning direction with the reciprocating movement of the carriage 20. The heteromorphic member 30 is configured to select one of the lever members 29 and move the selected lever members 29 based on the movement of the carriage 20.
The communication cut-off means is configured to include the lever members 29 that are provided to correspond to the flexible tube members 27 which form the suction channels. The lever members are configured to perform a lever operation so as to press and block corresponding tube members 29. The channel selecting means is configured to select the corresponding tube members 27 by selecting one of the lever members 29.
Next, the heteromorphic member 20 and the lever members 29 will be described in detail. In this example, it is assumed that there is only one lever member 29 and one tube member 27.
As shown in
A shaft insertion hole 36 is bored through the body portion 34 so that a shaft 35 is inserted into the shaft insertion hole 36. Continuous with the shaft insertion hole 36, an opening 39 is bored through the body portion 34 so as to receive a bias member 37 for pressing and biasing a friction member 38 against the outer circumferential surface of the shaft.
The shaft 35 is inserted into the shaft insertion hole 36, and the friction member 38 is pressed and biased against the outer circumferential surface of the shaft such that the bias member 37 and the friction member 38 are received in the opening 39. Together, the shaft 35, the bias member 37, and the friction member 38 constitute a friction clutch.
When the shaft 35 rotates in the direction of the arrow shown in
When the front end of the head portion 33 that is pivoted in a forward leaning manner receives force stronger than the frictional force acting between the shaft 35 and the friction member 38, the force causes the pivot operation of the lever member 29 to stop (referred to as a “pivot stopping force”). For example, the pivot stopping force occurs when a stopping member makes abutting contact with the front end of the head portion 33. Then, the shaft 35 slips over the friction member 38 and rotates idly, while the pivot operation of the lever member 29 is stopped. In this example, a heteromorphic member 30 functions as the stopping member (see
In this example, the heteromorphic member 30 is a plate member. In
The heteromorphic member 30 is fixed to the rear surface of the carriage 20, and the lever member 29 is disposed on the rear surface with the front end of the head portion 33 opposed to the heteromorphic member 30 (see
One portion of the heteromorphic member 30 includes a cutout portion 43 formed with a width which allows the insertion of the head portion 33 and the neck portion 41 of the lever member 29. On the side of the cutout portion 43 opposite the home position, an inclined surface 44 slopes down from the lower end of the cutout portion 43 toward the printable area and meets a horizontal portion 45. That is, the horizontal portion 45 is formed further out toward the printable area.
Next, descriptions will be made for the embodiment of the invention wherein the lever member 29 is selected based of the position of the carriage 20, using the lever member 29 and its friction clutch and the heteromorphic member 30 moving along with the reciprocating movement of the carriage 20.
First, the carriage 20 is moved into a position wherein the head portion 33 of the lever member 29 opposes the cutout portion 43 of the heteromorphic member 30, as shown in
As shown in
Thereafter, as shown in
Meanwhile, to restore the communication of the suction channel, the carriage 20 is moved to a position (as shown in
Hereinabove, selection of the lever members 29 was described assuming that there is one lever member 29 by way of example. Hereinafter, descriptions will be made of the case where one lever member 29 is selected from the first and second lever members 29a and 29b.
As illustrated in the drawings, the width of the cutout portion 43 of the heteromorphic member 30 is sized to allow individual insertion of the first or second lever members 29a and 29b but not simultaneous insertion of both members.
As shown in
As shown in
As shown in
As described above, the channel selecting means of the present embodiment is configured to include a lever selecting section provided in the carriage 20 and operable to select one or more of the lever members 29 to be operated on the basis of the position of the carriage 20. The lever members 29 capable of pivoting back and forth with the driving of the paper feeding motor 13 serving as the lever driving means, and the carriage 20 is provided with the heteromorphic member 30, which acts as the drive stopping member that makes contact with the lever members 29 in order to stop the lever members 29. The lever selecting means is the cutout portion 43 that is bored through the heteromorphic member 30 as the drive stopping means. The lever member 29 to be operated is selected when the lever member 29 is inserted into the cutout portion 43 by the driving of the lever driving means.
In the present embodiment, the channel cut-off means includes a lever activating section provided in the carriage 20 which allows the lever members 29 selected by the lever selecting section to perform the lever operation while the carriage 20 moves. The lever activating section is the inclined surface 44 that presses the selected lever members 29 so as to perform the lever operation while the carriage 29 is moving. The lever members are selected when they are inserted into the cutout portion 43 by the driving of the lever driving means. The communication cut-off means cuts off the suction channel of the tube member 27 corresponding to the lever member.
Using this arrangement, the recording apparatus of the present embodiment is able to select the cap spaces 25a and 25b for suction and the selection of the recording heads 24a and 24b for cleaning.
First, the case where the first lever member 29a is selected for a lever operation will be described. During this process, the first tube member 27a is blocked while maintaining the communication of the second tube member 27b, and a suction operation is performed on the second suction space 25b, causing a cleaning operation to be performed on the second recording head 24b.
As shown in
As described above, by rotating the shaft 35 in this state, the head portion 33a of the first lever member 29a is inserted into the cutout portion 43 and is thus selected for the lever operation, while the head portion 33b of the second lever member 29b makes contact with the plate portion of the heteromorphic member 30 and thus stops the pivot operation of the second lever member 29b. The first lever member 29a is pivoted until the rear end of the head portion 33a is disposed at a height corresponding to the inclined surface 44, and then the pivot operation thereof is stopped. Then, the carriage 20 is further moved toward the home position and the first lever member 29a is pivoted in such a way that the rear end of the head portion 33a is pressed against the inclined surface 44, causing the first lever member 29a to perform the lever operation. With the lever operation, the pressing portion 40 of the first lever member 29a is pressed and blocked in such a way that the inner surfaces thereof are in close contact with each other. Accordingly, the communication of the suction channel formed by the first tube member 27a is cut off.
Subsequently, the cap member 31 is moved upward to bring the upper end of the cap member 31 into close contact with the nozzle faces of the first and second recording heads 24a and 24b. Then, the nozzle faces of the first recording head 24a are capped by the first cap space 25a, and the nozzle faces of the second recording head 24b are capped by the second cap space 25b.
As shown in
Next, descriptions will be made for the case where the second lever member 29b is selected for a lever operation, the second tube member 27b is blocked while maintaining the communication of the first tube member 27a, and a suction operation is performed on the first suction space 25a, causing a cleaning operation to be performed on the first recording head 24a.
As shown in
As described above, by rotating the shaft 35 in this state, the head portion 33b of the second lever member 29b is inserted into the cutout portion 43 and is thus selected for the lever operation, while the head portion 33a of the first lever member 29a makes contact with the plate portion of the heteromorphic member 30, causing the pivot operation of the first lever member 29a to stop. The second lever member 29b is pivoted until the rear end of the head portion 33b is disposed at a height corresponding to the inclined surface 44, wherein the pivot operation is stopped. Subsequently, the carriage 20 is further moved toward the home position. At this time, the second lever member 29b is pivoted in such a way that the rear end of the head portion 33b is pressed against the inclined surface 44, causing the second lever member 29b to perform the lever operation. During the lever operation, the pressing portion 40 of the second lever member 29b is pressed in such a way that the inner surfaces of the pressing portion 40 and the tube seat 28 thereof are in close contact with each other, causing the communication of the suction channel formed by the second tube member 27b to be cut off.
Subsequently, the cap member 31 is moved upward to bring the upper end of the cap member 31 into close contact with the nozzle faces of the first and second recording heads 24a and 24b. Then, the nozzle faces of the first recording head 24a are capped by the first cap space 25a, and the nozzle faces of the second recording head 24b are capped by the second cap space 25b.
As shown in
Next, descriptions will be made for the case where neither the first nor the second lever members 29a and 29b are selected for a lever operation, meaning that the communication of the first and second tube members 27a and 27b is maintained, and a suction operation is performed on both the first and second suction spaces 25a and 25b, causing a cleaning operation to be performed on both the first and second recording heads 24a and 24b.
As shown in
As described above, by rotating the shaft 35, the head portions 33a and 33b of the first and second lever members 29a and 29b make contact with the plate portion of the heteromorphic member 30 and thus the pivot operations of the first and second lever members 29a and 29b are stopped. Next, the carriage 20 is further moved toward the home position. At this time, since neither the first nor the second lever members 29a and 29b perform the lever operation, the communication of the suction channels formed by the first and second tube members 27a and 27b is maintained.
Subsequently, the cap member 31 is moved upward to bring the upper end of the cap member 31 into close contact with the nozzle faces of the first and second recording heads 24a and 24b. Then, the nozzle faces of the first recording head 24a are capped by the first cap space 25a, and the nozzle faces of the second recording head 24b are capped by the second cap space 25b.
As shown in
Using the embodiment described above, the following advantages can be achieved.
According to one embodiment of the invention, the suction channels are maintained or cut off based on the position of the carriage 20. By driving the suction pump 26 in this state, liquid may be sucked from the nozzles corresponding to the cap spaces 25 which correspond to the suction channels where the communication is maintained, while the liquid remains in the nozzles in the cap spaces 25 wherein the suction channels are cut off. In this way, it is possible to select, among the plurality of cap spaces 25, a cap space for liquid suction from the plurality of suction channels, based on the position of the carriage 20. That is, since the suction channels are selected by the movement of the carriage 20, it is not necessary to have the rotating cam or the sensor. Therefore, it is possible to select the cap space 25 for suction at low cost without complicating installation work. In addition, since the selection of suction channels is performed using the carriage 20 which is typically subjected to highly precise positioning or movement control, it is possible to select the cap for suction in a secure manner.
Hereinafter, a second embodiment of the invention will be described with reference to
The first embodiment was described for the case where two recording heads 24a and 24b are provided to correspond to two cap spaces 25a and 25b, two tube members 27a and 27b, two tube seats 28a and 28b, and two lever members 29a and 29b, respectively.
In the present embodiment, one recording head 24 is provided with a plurality of nozzle arrays (i.e., four nozzle arrays are provided for each ink color of Y, M, C, and K). In addition, first to fourth cap spaces 25a, 25b, 25c, and 25d are prepared in the cap member 31 to correspond to the nozzle arrays. In addition, first to fourth tube members 27a, 27b, 27c, and 27d, first to fourth tube seats 28a, 28b, 28c, and 28d, first to fourth lever members 29a, 29b, 29c, and 29d are provided to correspond to the first to fourth cap spaces 25a, 25b, 25c, and 25d, respectively.
With such an arrangement, it is possible to cut off the communication of the first to fourth tube members 27a to 27d individually for each of the nozzle arrays.
Specifically, several lever members may be operated so as to maintain the communication of only one tube member while cutting off the communication of the remaining tube members, causing a cleaning operation to be performed on only one nozzle array corresponding to the tube member for which the communication is maintained. Alternatively, several lever members may be operated so as to maintain some of the tube members while cutting off the communication of the remaining tube members, whereby a cleaning operation is performed on several nozzle arrays corresponding to the tube members for which the communication is maintained. Alternatively, only one lever member may be operated so as to cut off the communication of only one tube member while maintaining the communication of the remaining tube members, whereby a cleaning operation is performed on several nozzle arrays corresponding to the remaining tube members for which the communication is maintained.
In the present embodiment, the operation in which only one lever member 29 is operated so as to cut off the communication of the tube member 27 is substantially the same as that of the first embodiment. Meanwhile, when several lever members 29 are operated so as to cut off the communication of the tube members 27, the lever members 29 are selected for a lever operation in the order of their proximity to the printable area disposed opposite the home position. That is, the lever member 29 disposed closest to the printable area is first inserted into the cutout portion 43 and is then moved to a position for a lever operation, activated by the pressing of the inclined surface 44 by the movement of the carriage 20. At this time, with the movement of the carriage 20, the lever member 29 disposed next to one disposed closer to the printable area is moved to the cutout portion 43 and is selected for a lever operation. In this manner, the remaining lever member 29 disposed close to the home position are sequentially selected for a lever operation.
Modifications
The invention is not limited to the embodiments described above, but may be modified in various ways.
In the above-described embodiments, the suction pump may employ various pumps including a tube pump, a piston pump, and a diaphragm pump.
Hereinabove, the present invention was described in association with an ink jet recording apparatus having an ink jet recording head for image recording, as an example of a liquid ejecting apparatus. Examples of liquid ejecting apparatuses to which the invention may be applied include: an apparatus having a coloring material ejecting head used for manufacturing a color filer such as a liquid-crystal display or the like; an apparatus having an electrode material (conductive paste) ejecting head used for forming electrodes, such as an organic EL display or a field emission display (FED) or the like; an apparatus having a bio-organic substance ejecting head used for manufacturing a bio-chip; an apparatus having a sample ejecting head serving as a precision pipette; and the like.
Number | Date | Country | Kind |
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2006-200400 | Jul 2006 | JP | national |
Number | Name | Date | Kind |
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6467872 | Yamada et al. | Oct 2002 | B1 |
Number | Date | Country |
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09-131882 | May 1997 | JP |
10-211717 | Aug 1998 | JP |
11-170562 | Jun 1999 | JP |
2001-347689 | Dec 2001 | JP |
2004-358792 | Dec 2004 | JP |
2005-329693 | Dec 2005 | JP |
Number | Date | Country | |
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20080018698 A1 | Jan 2008 | US |