DESCRIPTION
Fluid ejection device

BACKGROUND
1. Technical Field
[0001]
The present invention relates to fluid ejection device having a fluid ejection head that ejects a fluid as droplets onto a medium.
2. Related Art
[0002]
Fluid ejection devices are used in many different fields. One example of a fluid ejection device is an inkjet recording device having an inkjet head as a fluid ejection head that ejects ink onto recording paper. In an inkjet recording device, some of the ink droplets (fluid droplets) that are ejected from the inkjet head may become ink mist (minute fluid droplets) that becomes airborne inside the cabinet. This airborne ink mist can stick to parts inside the cabinet and cause various problems. Various methods have therefore been proposed for dealing with this ink mist in an inkjet recording device. For example, JP-A-H10-264412 discloses a method of providing a charged member inside the inkjet recording device and actively capturing the airborne ink mist.
[0004]
The charged member is preferably disposed opposite the range of movement of the inkjet head that produces the ink mist. The case member covering the top of the movement range can conceivably be used as the place opposite the movement range of the inkjet head. An access cover that opens and closes during maintenance, such as when replacing an ink cartridge, is commonly disposed to this case member. If the charged member is disposed to this access cover, the entire movement range of the inkjet head can be covered, and replacing a charged member that has become soiled is simple, for example. However, opening the access cover exposes the charged member that attracted the ink mist, and the user's hand, clothing, or other article can touch the charged member and become soiled.

SUMMARY
[0005]
The present invention is directed to solving at least part of the foregoing problem, and can be achieved by the embodiments and examples described below.
[0006]
Example 1: A fluid ejection device characterized by: a carriage on which a fluid ejection head that ejects fluid droplets to a recording medium is mounted; a carriage moving mechanism the moves the carriage bidirectionally in a direction intersecting the direction the recording medium is conveyed; and an outside case with an access cover that opens at least part of the carriage movement range of the carriage; the access cover having a plurality of ribs of a specific height on the surface facing the carriage movement range when closed, and a charged member disposed between the plural ribs so that the adsorption surface that adsorbs fluid mist is exposed.
[0007]
With this configuration, ink mist, which is minute fluid droplets that become airborne due to air flow accompanying the movement of the fluid ejection head that ejects ink droplets as fluid droplets and the carriage that carries the fluid ejection head, is adsorbed by the adsorption surface of a charged member disposed on the surface of the access cover facing the carriage movement range. The charged member of which the adsorption surface becomes soiled by adsorbing ink mist is disposed between a plurality of ribs of a specific height disposed to the access cover. Direct contact between the user's hand or clothing with the soiled charged member can therefore be reduced even when the user opens the access cover and performs maintenance tasks. As a result, the user getting dirty can be prevented.
[0008]
Example 2: In the fluid ejection device described above, the plural ribs are formed on the access cover along the direction in which the carriage is moved by the carriage moving mechanism; and the charged member is disposed between the plural ribs.
[0009]
Ink mist produced from a fluid ejection head that ejects ink droplets is often dispersed by the air flow accompanying movement of the carriage. In this configuration, a band-shaped charged member is disposed along the direction of carriage movement in which the ink mist disperses. As a result, airborne ink mist can be efficiently adsorbed (captured). The charged member is also disposed between the plural ribs of a specific height. Direct contact between the user's hand or clothing with the soiled charged member can therefore be reduced even when the user opens the access cover and performs maintenance tasks.
[0010]
Example 3: The fluid ejection device described above, wherein: the charged member is a sheet and is disposed to the surface of the access cover facing the carriage movement range; the plural ribs are formed on a charged member cover that covers the charged member sheet; and the charged member cover has a rectangular opening between the plural ribs, and is removably attached to the access cover with the plural ribs aligned with the direction the carriage is moved by the carriage moving mechanism.
[0011]
Ink mist produced from a fluid ejection head that ejects ink droplets is often dispersed by the air flow accompanying movement of the carriage. In this configuration, a sheet-like charged member is exposed from rectangular openings between the plural ribs that are disposed along the direction of carriage movement in which the ink mist disperses. As a result, airborne ink mist can be efficiently adsorbed (captured). The adsorption surface of the charged member is also exposed from the rectangular openings formed between plural ribs of a specific height. Direct contact between the user's hand or clothing with the soiled charged member can therefore be reduced even when the user opens the access cover and performs maintenance tasks.
[0012]
Example 4: In the fluid ejection device described above, the charged member cover is sized to cover the entire charged member sheet.
[0013]
With this configuration the charged member cover can cover the entire charged member sheet. As a result, the user can be prevented from directly contacting the charged member that became soiled by adsorbing ink mist.
[0014]
Example 5: The fluid ejection device described above, wherein a second rib of a specific height that is lower than the plural ribs is formed between the plural ribs.
[0015]
This configuration can ensure the strength of the plural ribs.
[0016]
Example 6: The fluid ejection device described above, wherein the charged member is removably attached to the access cover.
[0017]
This configuration enables replacing a charged member soiled by adsorbing ink mist with a new charged member.
[0018]
Example 7: The fluid ejection device described above, wherein the charged member is a charged filter made from a porous electret.
[0019]
This configuration can use a charged filter made from a porous electret as the charged member. A charged filter is a configuration made from a porous electret structure, such as a non-woven cloth made with polypropylene or other thermosetting polymer. An electret is a dielectric that holds a permanently polarized state. More specifically, by using a charged filter as the charged member, ink mist can be captured with no electrical consumption by means of a simple configuration.
Other objects and attainments together with a fuller understanding of the invention will become apparent and appreciated by referring to the following description and claims taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an oblique view from the front of a printer applying the invention.
FIG. 2 is a vertical section view showing the internal configuration of the printer.
FIG. 3 is an oblique view from the front of the printer without the outside case.
FIG. 4 illustrates an access cover and charged member according to a first embodiment of the invention.
FIG. 5 illustrates an access cover and charged member according to a second embodiment of the invention.

DESCRIPTION OF EMBODIMENTS
[0021]
An inkjet printer is described by way of example with reference to the accompanying figures as a fluid ejection device according to the invention. An inkjet printer ejects ink (fluid) as ink droplets (fluid droplets) from an inkjet head as the fluid ejection head, and prints information on printing paper as the recording medium. Note that the scale and size of members and parts shown in the figures referenced below may differ from the actual scale and size for convenience of description and illustration.
[0022]
General configuration of a printer
The general configuration of an inkjet printer (referred to below as simply a printer) applying the invention is described first with reference to FIG. 1. FIG. 1 is an external oblique view from the front of a printer according to the invention. Note that the transverse axis X shown in FIG. 1 represents the direction across the width of the printing paper, the longitudinal axis Y denotes the direction in which the printing paper is discharged, and the vertical axis Z denotes the direction perpendicular to the transverse axis X and the longitudinal axis Y.
[0023]
As shown in FIG. 1, the printer 10 has a main printer unit 12 and a inverting unit 13. The main printer unit 12 is a basically rectangular box-like shape that is long widthwise to the printer (on the transverse axis X). A recess 14 is formed in the middle of the back of the main printer unit 12, and the inverting unit 13 is installed here. The inverting unit 13 is a unit for inverting the front and back sides of the printing paper P, which is a form of sheet recording media (see FIG. 2), and then returning the inverted paper into the main printer unit 12.
[0024]
A paper cassette loading unit 15 is disposed to the main printer unit 12. The paper cassette loading unit 15 opens to the front on the longitudinal axis Y of the printer 10 at a position toward the bottom on the vertical axis Z of the printer 10 in the front of the main printer unit 12. A paper cassette 16 can be loaded from the front on the longitudinal axis Y to the paper cassette loading unit 15. A paper discharge tray 17 is above the paper cassette loading unit 15 on the vertical axis Z. The front end of the paper discharge tray 17 protrudes to the front on the longitudinal axis Y from the main printer unit 12. A paper exit 18 extending toward the back on the longitudinal axis Y is formed above the paper discharge tray 17.
[0025]
An operating panel 19a is disposed to the outside case 20 as the cabinet of the main printer unit 12 at the front above the paper exit 18. The operating panel 19a includes a power switch and state indicators. Rectangular access doors 19b, 19c are disposed to the outside case 20 at the front of the printer on opposite sides of the paper discharge tray 17 and paper exit 18. When the access doors 19b, 19c are open, the ink cartridge loading unit not shown in the figure is exposed and the ink cartridges not shown in the figure can be replaced.
[0026]
The top part 20a of the outside case 20 of the printer is substantially flat, and in the middle portion thereof a rectangular opening 21 is formed that exposes to the outside part of the carriage movement range S (see FIG. 3) through which the carriage 37 described below (see FIG. 2 and FIG. 3) moves. An access cover 60 is attached to this opening 21.
[0027]
The access cover 60 is a rectangular panel sized to cover the opening 21 disposed to the top part 20a of the outside case 20, and can open and close freely in the direction of arrow M on an axis of rotation 63 coupled on one long side 60a to the one side 21a of the opening 21 on the longitudinal axis Y. The access cover 60 is normally closed when the printer 10 is printing, and is opened to replace ink cartridges and to handle problems such as paper jams. The access cover 60 is described in detail below.
[0028]
Internal configuration of the printer
The internal configuration of the printer is described next with reference to FIG. 2 and FIG. 3. FIG. 2 is vertical section view showing the internal configuration of the printer, and FIG. 3 is an oblique view from the back of the printer without the outside case. Note that the transverse axis X, longitudinal axis Y, and vertical axis Z shown in FIG. 2 and FIG. 3 are the same as the transverse axis X, longitudinal axis Y, and vertical axis Z shown in FIG. 1.
[0029]
As shown in FIG. 2, a paper supply path 22, printer-side conveyance path 23, and inverting conveyance path 24 for conveying the printing paper P are formed inside the printer 10. The paper supply path 22 and printer-side conveyance path 23 are formed inside the outside case 20 of the main printer unit 12, and the inverting conveyance path 24 is formed inside the inverting unit 13.
[0030]
The paper supply path 22 is a conveyance path that conveys printing paper P of a specific size from a stack in the paper cassette 16 to the printer-side conveyance path 23. The paper supply path 22 and the paper cassette 16 are disposed below the printer-side conveyance path 23 on the vertical axis Z. The paper supply path 22 extends diagonally up from the back end of the paper cassette loading unit 15 on the longitudinal axis Y, curves and connects to the printer-side conveyance path 23 along the longitudinal axis Y. Printing paper P stored in the paper cassette 16 is fed by the delivery roller 25 to the paper supply path 22. The supplied printing paper P is fed one sheet at a time through the nipping part of a pressure roller 26 and a conveyance roller 27, and conveyed toward the printer-side conveyance path 23 through the nipping part of the conveyance roller 27 and a follower roller 28.
[0031]
The printer-side conveyance path 23 is a conveyance path that extends substantially horizontally in a straight line on the longitudinal axis Y to the paper exit 18. A paper feed roller pair 31, a print mechanism 30 described below, a first discharge roller pair 33, and a second discharge roller pair 34 are disposed in order along the printer-side conveyance path 23 from the upstream side to the downstream side in the conveyance direction of the printing paper P. The print position of the print mechanism 30 is referred to below as the print position A.
[0032]
The conveyance roller 27 and follower roller 28, the paper feed roller pair 31, the first discharge roller pair 33, and the second discharge roller pair 34 embody a printer-side conveyance mechanism 41 that conveys the printing paper P through the printer-side conveyance path 23. The printer-side conveyance mechanism 41 is driven by a conveyance motor 42 disposed to the transverse axis X of the paper cassette 16. The printer-side conveyance mechanism 41 conveys the printing paper P forward on the longitudinal axis Y by driving the conveyance motor 42 forward, and conveys the printing paper P in reverse on the longitudinal axis Y by driving the conveyance motor 42 in reverse. Printing by the print mechanism 30 occurs while the printing paper P passes the print position A forward on the longitudinal axis Y.
[0033]
The inverting conveyance path 24 is disposed below the printer-side conveyance path 23 on the vertical axis Z, and is a conveyance path that forms a loop on the vertical axis Z. A first inverting conveyance roller pair 51 and a second inverting conveyance roller pair 52 are disposed as an inverting conveyance mechanism 50 that conveys the printing paper P through the inverting conveyance path 24. The inverting conveyance mechanism 50 is driven by an inverting conveyance motor 53 disposed on the inside of the inverting conveyance path 24. The inverting conveyance mechanism 50 conveys the printing paper P supplied from the printer-side conveyance path 23 through the inverting conveyance path 24 clockwise as seen in FIG. 2. The printing paper P is reversed front and back by passing through the inverting conveyance path 24, and is then returned to the printer-side conveyance path 23.
[0034]
The print mechanism 30 is described next. As shown in FIG. 2 and FIG. 3, the print mechanism 30 includes a printhead 32, a carriage 37, and a carriage moving mechanism 39. The printhead 32 is an inkjet head as an example of a fluid ejection head, and is positioned above the printer-side conveyance path 23. A platen 35 is disposed with a specific gap to the printhead 32 at the print position A opposite the printhead 32 on the printer-side conveyance path 23. The carriage 37 carries the printhead 32 with the ink ejecting face not shown of the printhead 32 facing the printer-side conveyance path 23.
[0035]
The carriage moving mechanism 39 includes a carriage guide rail 38 extending on the transverse axis X, and a carriage motor 40. One end of the carriage guide rail 38 is supported by a first side frame 45 that extends on the longitudinal axis Y and vertical axis Z on one side of the transverse axis X. The first side frame 45 is disposed with a specific gap to the printer-side conveyance path 23. The other end of the carriage guide rail 38 is supported by a second side frame 46 that extends parallel to the first side frame 45 on the other side of the transverse axis X. The second side frame 46 is disposed with a specific distance to the first side frame 45 with the printer-side conveyance path 23 therebetween.
[0036]
The carriage moving mechanism 39 includes a pair of pulleys 47 respectively disposed near the first side frame 45 and near the second side frame 46, and a timing belt 48 that is mounted on the pair of pulleys 47. The timing belt 48 is mounted along the carriage guide rail 38. The carriage 37 is connected to the timing belt 48, and drive power from the carriage motor 40 is transferred to one of the pair of pulleys 47. Therefore, the timing belt 48 revolves as driven by the carriage motor 40, and the carriage 37 therefore moves bidirectionally on the transverse axis X along the carriage guide rail 38. This area is the carriage movement range S of the printhead 32 and the carriage 37. A flexible ink channel not shown is connected to the printhead 32, and the printhead 32 is connected to an ink cartridge not shown through the ink channel. When the printhead 32 moves, the ink channel deforms according to the movement of the printhead 32.
[0037]
Printer operation
Operation of the printer is described next with reference to FIG. 2 and FIG. 3. During double-sided printing in the printer 10, the printing paper P stored in the paper cassette 16 is first delivered by the delivery roller 25 to the paper supply path 22. The conveyance motor 42 is also driven forward, and the printing paper P delivered to the paper supply path 22 is conveyed by the pressure roller 26 and conveyance roller 27, and fed to the printer-side conveyance path 23. The printing paper P fed into the printer-side conveyance path 23 is then conveyed forward on the longitudinal axis Y by the printer-side conveyance mechanism 41, and passes the print position A. At the print position A, the printing operation of ejecting ink droplets as fluid droplets while moving the printhead 32 bidirectionally on the transverse axis X is executed synchronized to the conveyance operation of the printing paper P. As a result, desired information is printed to the surface of the printing paper P.
[0038]
When printing on the surface of the printing paper P ends, the conveyance motor 42 is driven in reverse. The inverting conveyance motor 53 is also driven. By driving the conveyance motor 42, the printing paper P is conveyed to the back on the longitudinal axis Y by the printer-side conveyance mechanism 41, and is fed from the printer-side conveyance path 23 to the inverting conveyance path 24. The printing paper P fed into the inverting conveyance path 24 is then conveyed through the inverting conveyance path 24 by the inverting conveyance mechanism 50, and is returned to the printer-side conveyance path 23 with the front and back reversed.
[0039]
The printing paper P returned to the printer-side conveyance path 23 is conveyed forward on the longitudinal axis Y by the printer-side conveyance mechanism 41, and passes the print position A of the printhead 32 again. At the print position A, the printing operation of ejecting ink droplets while moving the printhead 32 bidirectionally on the transverse axis X is executed synchronized to the conveyance operation of the printing paper P. As a result, the back side of the printing paper P is printed. When printing the back of the printing paper P is completed, the printer-side conveyance mechanism 41 conveys the printing paper P further forward on the longitudinal axis Y and discharges the printing paper P from the paper exit 18.
[0040]
Embodiment 1
Access cover and charged member according to a first embodiment
An access cover and charged member according to the first embodiment of the invention are described below with reference to FIG. 1 and FIG. 4. FIG. 4 illustrates the access cover and charged member according to the first embodiment of the invention, and more particularly illustrates the surface that faces the carriage movement range when the access cover is closed. Note that the transverse axis X, longitudinal axis Y, and vertical axis Z shown in FIG. 4 are the same as the transverse axis X, longitudinal axis Y, and vertical axis Z shown in FIG. 1.
[0041]
In a printer 10 using an inkjet head as the printhead 32 described above (see FIG. 2 and FIG. 3), a portion of ink droplets ejected from the printhead 32 during the printing operation and the flushing operation may separate from the ink droplets flying toward the printing paper P, and become airborne ink mist (minute ink droplets) inside the outside case 20 before reaching the printing paper P. This airborne ink mist can land on and soil parts inside the outside case 20. Furthermore, because the ink mist is charged by the charge of the nozzle plate not shown of the printhead 32 and the charge of the platen 35, problems can result when the ink mist lands on other charged parts, such as sensors and the control board.
[0042]
As a result of experiments, the inventor discovered that a charged member is excellent at capturing ink mist. The invention is based on this discovery. Such a charged member is called and marketed as a charged filter 80, and is used for capturing and removing dust from the air. Each charged filter 80 is made from a porous electret structure, such as a non-woven cloth made with polypropylene or other thermosetting polymer. An electret is a dielectric that holds a permanently polarized state. One side of the charged filter 80 is an adsorption surface 80a, and the other side is an installation surface 80b. Note that charged filter 80 is used below when referring to the entire charged filter as the charged member, and individual charged filters are referred to as a first charged filter 81, second charged filter 82, and so forth.
[0043]
As shown in FIG. 1, the access cover 60 in the first embodiment of the invention is a rectangular panel sized to cover the opening 21 disposed to the top part 20a of the outside case 20, one long side 60a is coupled to the one side 21a of the opening 21 on the longitudinal axis Y, and the access cover 60 is attached to open and close freely in the direction of arrow M on an axis of rotation 63 at this part. When closed, the access cover 60 covers most of the carriage movement range S described above.
[0044]
As shown in FIG. 4, a rib 62 with a specific height H is disposed to the surface 61 of the access cover 60 facing the carriage movement range S along the direction the carriage 37 is moved by the carriage moving mechanism 39, that is, on the transverse axis X. A plurality of ribs 62 are disposed at a specific pitch N on the longitudinal axis Y. A first charged filter 81 shaped like a band is affixed with the adsorption surface 81a exposed between adjacent ribs 62. The first charged filter 81 can be freely installed and removed with the installation surface 81b facing the surface 61 between the ribs 62. Various methods of removably affixing the charged filter may be used, including using an adhesive so the filter can be removed, or a hook or other temporary fastener that can be easily disconnected. Any known removable attachment technology can be used as the installation method.
[0045]
A second rib not shown with a height lower than the rib 62 could also be disposed between ribs 62 along the transverse axis X with a specific gap therebetween. In this event, the first charged filter 81 is sized to fit between the rib 62 and the second rib.
[0046]
In the printer 10 comprised as described above, the adsorption surface 81a of the band-shaped first charged filter 81 disposed to the surface 61 of the access cover 60 opposite the carriage movement range S adsorbs ink mist produced in conjunction with movement of the carriage 37 and ejecting ink droplets from the printhead 32. The adsorption surface 81a of the first charged filter 81 that adsorbs ink mist and becomes soiled is located between a plurality of ribs 62 of a specific height H disposed to the access cover 60. Direct contact between the user's hand or clothing with the soiled charged member can therefore be reduced even when the user opens the access cover 60 and performs maintenance tasks. As a result, the user getting dirty can be prevented.
[0047]
The band-shaped first charged filter 81 is affixed removably between plural ribs 62 of the access cover 60. As a result, a first charged filter 81 soiled by adsorbing ink mist can be appropriately replaced with a new first charged filter 81 as needed depending upon how dirty the first charged filter 81 has become.
[0048]
Embodiment 2
Access cover and charged member according to a second embodiment
An access cover and charged member according to the second embodiment of the invention are described below with reference to FIG. 1 and FIG. 5. FIG. 5 illustrates the access cover and charged member according to the second embodiment of the invention, and more particularly is an exploded oblique view illustrating the surface that faces the carriage movement range when the access cover is closed. Note that configurations and content that are the same as in the first embodiment are identified with the same reference numerals below, and further description thereof is omitted. Note, further, that the transverse axis X, longitudinal axis Y, and vertical axis Z shown in FIG. 5 are the same as the transverse axis X, longitudinal axis Y, and vertical axis Z shown in FIG. 1.
[0049]
Like the access cover 60 according to the first embodiment of the invention shown in FIG. 1, the access cover 70 according to the second embodiment is a rectangular panel sized to cover the opening 21 disposed to the top part 20a of the outside case 20, and is attached to open and close freely in the direction of arrow M on an axis of rotation 63. This access cover 70 also covers most of the carriage movement range S described above when closed.
[0050]
As shown in FIG. 5, the access cover 70 has a main section 71, a second charged filter 82, and charged member cover 73. The main section 71 has substantially the same construction as the access cover 60 according to the first embodiment of the invention, and functions as a basic access cover 70. The second charged filter 82 is formed as a rectangular sheet, and is removably affixed with the installation surface 82b facing the main section 71. As a result, the adsorption surface 82a of the second charged filter 82 faces the carriage movement range S when the access cover 70 is closed. Note that various methods of removably affixing the charged filter may be used, including using an adhesive so the filter can be removed, or a hook or other temporary fastener that can be easily disconnected. Any known removable attachment technology can be used as the installation method.
[0051]
The charged member cover 73 is molded from plastic, for example, and is made in a rectangular shape of a size that covers the adsorption surface 82a of the second charged filter 82. The charged member cover 73 has a rib 75 of a specific height H disposed along the long side of the rectangle. A plurality of ribs 75 are disposed at a specific pitch N along the short side. A long rectangular through-hole 77 is formed between the ribs 75.
[0052]
The charged member cover 73 is removably attached to the main section 71 through the second charged filter 82 with the plural ribs 75 aligned with the direction the carriage 37 is moved by the carriage moving mechanism 39, that is, along the transverse axis X. Note that various methods of removably affixing the charged member cover 73 may be used, including using a hook or other temporary fastener that can be easily disconnected. Any known removable attachment technology can be used as the installation method.
[0053]
In the printer 10 comprised as described above, the adsorption surface 82a of the second charged filter 82 exposed through the rectangular through-holes 77 in the charged member cover 73 attached to the access cover 70 (main section 71) can adsorb ink mist produced in conjunction with movement of the carriage 37 and ejection of ink droplets from the printhead 32. The adsorption surface 82a of the second charged filter 82 that adsorbs ink mist and becomes soiled is located between a plurality of ribs 75 of a specific height H disposed to the charged member cover 73. Direct contact between the user's hand or clothing with the soiled charged member can therefore be reduced even when the user opens the access cover 60 and performs maintenance tasks. As a result, the user getting dirty can be prevented.
[0054]
The charged member cover 73 is removably attached to the main section 71 of the access cover 70. As a result, the second charged filter 82 that adsorbed ink mist and became soiled can be replaced with a new second charged filter 82 by removing the charged member cover 73. The charged member cover 73 that became soiled with ink mist can also be easily cleaned.
The invention being thus described, it will be obvious that it may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims.

WE CLAIM:

1. A fluid ejection device comprising:
a carriage on which a fluid ejection head that ejects fluid droplets to a recording medium is mounted;
a carriage moving mechanism the moves the carriage bidirectionally in a direction intersecting the direction the recording medium is conveyed; and
an outside case with an access cover that opens at least part of the carriage movement range of the carriage;
the access cover having a plurality of ribs of a specific height on the surface facing the carriage movement range when closed, and
a charged member disposed between the plural ribs so that the adsorption surface that adsorbs fluid mist is exposed.

2. The fluid ejection device described in claim 1, wherein:
the plural ribs are formed on the access cover along the direction in which the carriage is moved by the carriage moving mechanism; and
the charged member is disposed between the plural ribs.

3. The fluid ejection device described in claim 1, wherein:
the charged member is a sheet and is disposed to the surface of the access cover facing the carriage movement range;
the plural ribs are formed on a charged member cover that covers the charged member sheet; and
the charged member cover has a rectangular opening between the plural ribs, and is removably attached to the access cover with the plural ribs aligned with the direction the carriage is moved by the carriage moving mechanism.

4. The fluid ejection device described in claim 3, wherein:
the charged member cover is sized to cover the entire charged member sheet.

5. The fluid ejection device described in any of claims 1 to 4, wherein:
a second rib of a specific height that is lower than the plural ribs is formed between the plural ribs.

6. The fluid ejection device described in any of claims 1 to 5, wherein:
the charged member is removably attached to the access cover.

7. The fluid ejection device described in any of claims 1 to 6, wherein:
the charged member is a charged filter made from a porous electret.