JP2013107237A - Liquid ejection apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid ejection apparatus in which the drying efficiency of a droplet ejected to a medium is improved, and that can efficiently dry by a limited heat capacity, is small in the size, and achieves a high image quality.SOLUTION: The liquid ejection apparatus includes infrared heaters 15 that emit infrared to the ink droplet landed in a media 4 to be dried at either of both ends of the main scanning direction sides of a carriage 9, wherein the infrared heaters 15 are strung in a curvature shape at the neighborhood of a Y-axis guide member 10, and include a pair of power supply terminals 15a in the away position from the Y-axis guide member 10.

Description

  The present invention relates to a liquid ejection device including an infrared heating unit.

  An ink jet recording apparatus, which is an example of a liquid ejecting apparatus, includes an ejecting head that ejects ink droplets (droplets) such as aqueous pigment ink, solvent ink, and sublimation ink, and ink ejected from the ejection head to a medium (medium). In contrast, a fixing unit such as a heater and a drying fan is provided. The ejection head is mounted on a carriage that is scanned in the main scanning direction (medium width direction), and performs recording by fixing (drying) ink droplets ejected from the nozzles of the ejection head to the medium while scanning the carriage. Yes.

  An ink jet recording apparatus has been proposed in which a drying head is provided on the downstream side in the recording medium transport direction of a carriage mounted with a recording head and reciprocatingly moved in the main scanning direction in order to efficiently dry and fix the ink ejected onto the medium. . The drying means includes a straight carbon heater, a reflector, and a filter, and the entire width of the recording medium is dried with the reciprocation of the carriage by setting the carbon heater to the same width as the carriage. Patent Document 1, paragraphs [0029] and [0030]).

JP 2008-155485 A

  The drying means described above is provided on the downstream side in the recording medium conveyance direction from the recording head mounted on the carriage. That is, the landing position of the ink droplets ejected onto the recording medium and the heating position of the drying device are arranged back and forth in the recording medium conveyance direction. In order to increase the drying efficiency of the ink droplets that have landed on the recording medium, it is preferable to carry out directly above or in the vicinity of the ink droplets (nozzle position) that have landed on the recording medium. In the configuration of the above-mentioned Patent Document 1, there is a problem that the ink droplet drying efficiency is lowered because the landing position of the ink droplet and the heating position of the drying device are separated.

In addition, since the drying state of the ink droplets and the required amount of heat differ depending on the type of ink (water-based ink, solvent ink, etc.), efficient drying with a limited heat capacity of the heater as a heat source is also required.
Further, it is desirable to mount the discharge head closer to the guide member for guiding the carriage reciprocating scan to reduce the influence on the image quality due to the vibration accompanying the carriage reciprocating scan while miniaturizing the apparatus. For this reason, there is a need to arrange the heater close to the guide member in the sub-scanning direction in accordance with the discharge nozzle position.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a small-sized and high-quality liquid discharge apparatus that can improve the drying efficiency of droplets discharged onto a medium and can be efficiently dried with a limited heat capacity. .

  In order to solve the above problems, a liquid ejection apparatus according to the present invention has the following configuration. That is, a carriage is provided that includes a discharge head provided with discharge nozzles for discharging droplets to a recording medium, and reciprocally moves along a guide portion formed on a guide member provided along the main scanning direction. In addition, the liquid ejection device includes an infrared heater that radiates infrared rays to the droplets that have landed on the recording medium and dries on either side of the carriage in the main scanning direction, and the infrared heater includes the guide member A pair of power supply terminal portions are provided at positions near the curved shape in the vicinity and away from the guide member.

According to the above configuration, since the infrared heater is provided on either side of the carriage in the main scanning direction, the droplet immediately after landing on the medium can be dried by the infrared heater, so that the drying efficiency can be improved. it can.
In addition, since the infrared heater has a curved shape in the vicinity of the guide member and the pair of power supply terminal portions are formed at positions away from the guide member, the distance between the guide member and the infrared heater can be shortened. Accordingly, since the interval from the discharge nozzle to the guide member can be shortened, the positional accuracy of the discharge nozzle can be improved, and as a result, the print image quality can be improved and the apparatus can be downsized.

The infrared heater is preferably arranged with a predetermined pitch shift downstream from the upstream end in the medium transport direction of the nozzle row in the sub-scanning direction provided in the ejection head.
As a result, it is possible to increase the drying efficiency by supplying the amount of heat necessary for drying according to the discharge amount of the droplets while realizing miniaturization of the infrared heater. That is, an infrared heater is shifted to relatively reduce the degree of drying at a printing location where the amount of liquid droplets discharged onto the recording medium is small as in the recording operation of the first line in the carriage scanning direction, and the degree of drying is relatively weakened. Infrared heaters are placed at the printing locations where the amount of liquid droplets discharged onto the recording medium increases as in the subsequent recording operations, so that the drying efficiency is improved while reducing the size of the infrared heaters by relatively increasing the degree of drying. Can be improved.

A plurality of the infrared heaters may be provided, and may be arranged to be shifted in the sub-scanning direction by a predetermined pitch.
As a result, drying is performed with a relatively small amount of heat supplied from the infrared heater at a printing location upstream of the medium conveyance direction where the amount of droplets discharged onto the recording medium is small, and droplets onto the recording medium downstream of the medium conveyance direction In the printing area where the discharge amount of ink increases, the heat amount supplied from the infrared heater is relatively increased and drying is performed, so that the necessary heat amount is supplied according to the discharge amount of the droplets discharged onto the recording medium, and the optimum amount is obtained. It can be dried under conditions.
Also, by disposing a plurality of infrared heaters in the sub-scanning direction, a wide dry area can be taken from the position where the droplets land on the medium to the downstream side in the medium transport direction, so the droplet fixing property is good. Image quality can be improved.

The infrared heater is arranged such that one side thereof coincides with or shifts downstream from the upstream end in the medium conveyance direction of the ejection head, and the other side extends further downstream from the downstream end in the medium conveyance direction of the ejection head. May be.
As a result, the drying area by the infrared heater can be widened with respect to the recording medium from the position facing the ejection head to the position where the liquid droplets have already landed on the downstream side of the ejection direction from the ejection head. The image quality can be improved.

It is preferable that the infrared heater is formed in a U shape or an annular shape, and the pair of power feeding portions are arranged on the downstream side in the medium transport direction in a direction orthogonal to the guide member.
Accordingly, by using a U-shaped or annular infrared heater, the arrangement of the pair of power supply terminal portions is aligned in the same direction away from the downstream side in the medium transport direction in a direction orthogonal to the guide member. Easy assembly.

In addition, when the reflector which reflects the radiant heat of an infrared heater toward a medium is provided, and the said reflector is provided with the through-hole for heat radiation, it passes through the through-hole of the reflector heated by the infrared heater. It can be cooled by heat dissipation.
In addition, if a blower fan is provided on the cover to blow air through the through-hole, the heat dissipation of the reflector is increased and the drying efficiency is improved because the warm air is blown toward the medium on which the droplets are discharged.

A liquid equipped with a carriage mounted with a discharge head provided with discharge nozzles for discharging droplets to a recording medium and reciprocating along a guide portion formed on a guide member provided along the main scanning direction An ejection device, which is disposed at either end of the carriage in the main scanning direction and which is disposed at one end of a scanning range of the carriage, and an infrared heater that emits infrared rays to the recording medium to dry the recording medium A cleaning device for cleaning the discharge nozzles, wherein the infrared heater is provided so that the discharge head is closer to the carriage in the moving direction than a cleaning position facing the cleaning device. And
Thus, the infrared heater does not cross directly above the cleaning portion when moving in the main scanning direction to the cleaning position provided at one end of the carriage scanning range. Therefore, it is possible to prevent the cap surface of the head cap provided in the cleaning device from drying.

  According to the present invention, it is possible to provide a small-sized liquid ejection device that can improve the drying efficiency of droplets ejected on a recording medium and can be efficiently dried with a limited heat capacity and realizes high image quality. it can.

It is a schematic block diagram along the sheet conveyance of an inkjet recording device. 1 is an external perspective view of an ink jet recording apparatus. It is an expansion perspective view of a carriage part. It is the perspective view which looked at the infrared heater and the discharge head from the lower surface side. It is a bottom view of an infrared heater and a discharge head according to another example.

  Hereinafter, embodiments of a liquid ejection apparatus according to the present invention will be described in detail with reference to the drawings. Hereinafter, an ink jet recording apparatus will be described as an example of a liquid ejection apparatus. The main scanning direction indicates the direction in which the carriage reciprocates (Y-axis direction), and the sub-scanning direction indicates the medium (medium) conveyance direction (X-axis direction) orthogonal to the main scanning direction (FIG. 1, FIG. 1). 2).

  As shown in FIG. 1, the inkjet recording apparatus 1 uses, for example, a large and long roll sheet (polyester sheet or the like) as a recording medium (media). The media 4 fed from the feeding roll 3 wound around the feeding shaft 2 is conveyed to the platen 6 through the upstream tension bar 5.

  The platen 6 is provided with a transport device 7, and the medium 4 is transported by the transport device 7 to a recording position facing the ejection head 8 in the sub-scanning direction. The platen 6 that guides the conveyance while supporting the medium 4 may be provided with a heater for improving the fixing property of the ink.

The discharge head 8 is mounted on a carriage 9, and the carriage 9 is provided so as to be able to reciprocate along a Y-axis direction guide member (Y bar) 10 provided in the main scanning direction (media width direction). . In addition, the carriage 9 is integrally provided with an infrared heater 15 that emits infrared rays to the ink droplets that have landed on the medium 4 to dry them.
Recording is performed by ejecting ink droplets onto the medium 4 while the carriage 9 moves in the main scanning direction, and infrared rays are irradiated by the infrared heater 15 and the recording surface is dried by radiant heat. When the recording for one line is performed, the medium 4 is fed in the sub-scanning direction by the transport device 7 and the carriage 9 is scanned in the main scanning direction to start the next recording operation.

  The recording medium 4 is fed downstream by the tension roller 11 without slack, and is wound as a winding roll 14 on a winding shaft 13 via a downstream tension bar 12. An after heater (not shown) that promotes fixing of a recorded image is provided in the conveyance path on the downstream side of the tension roller 11.

  In FIG. 2, a blower fan 17 is provided at a plurality of locations along the longitudinal direction (main scanning direction) above the apparatus main body 16 to promote drying of ink droplets ejected to the medium 4 at the recording position. It is like that. Further, an ink cartridge 18 for supplying ink liquid to the ejection head 8 is provided on the upper portion of the apparatus main body 16. In the ejection head 8, ink (liquid) such as water-soluble inks such as M (magenta), Y (yellow), C (cyan), and K (black), sublimation ink, and the like from an ink cartridge 18 through an ink tube (not shown). ) Is supplied, and ink droplets are ejected from the ejection nozzle 8a (see FIG. 4) in accordance with the recording signal.

  As shown in FIG. 3, the carriage 9 on which the ejection head 8 is mounted reciprocates along a guide rail 10a (guide portion) formed on a Y-axis guide member 10 (Y bar) provided in the main scanning direction. Specifically, the carriage 9 is reciprocally linked to a part of an endless timing belt that is driven to rotate forward and backward by a drive source (not shown).

  As shown in FIG. 3, a second frame 9b is integrally provided adjacent to the first frame 9a on one end side of the carriage 9 in the main scanning direction. The first frame 9a is provided with a discharge head 8 (see FIG. 4) covered with a head cover 8b. In FIG. 4, a plurality of ejection heads 8 having ejection nozzles 8 a that eject ink droplets onto the medium 4 are mounted on the first frame 9 a of the carriage 9 in the head cover 8 b. Each discharge head 8 is positioned and supported so that the discharge nozzle 8a is exposed from a through hole 9c that passes through the first frame 9a.

  In FIG. 3, a second frame 9b is integrally provided adjacent to a first frame 9a provided on one end side of the carriage 9 in the scanning direction. An infrared heater 15 is provided on the second frame 9b. The infrared heater 15 is arranged to be shifted to the downstream side in the medium conveying direction with respect to the ejection head 8. The infrared heater 15 emits infrared rays to the ink droplets that have landed on the medium 4 and dries them by radiant heat. The infrared heater 15 may be provided on the other end side of the carriage 9 in the scanning direction. In this case, the cleaning device 19 (see FIG. 3) provided at the moving end of the carriage 9 is provided on the opposite side of the device main body 16 in the longitudinal direction. This is because the infrared heater is arranged so as not to cross the cleaning portion.

In FIG. 4, for example, a U-shaped or annular carbon heater is used as the infrared heater 15. By using a carbon heater, drying efficiency can be improved by irradiating infrared rays suitable for moisture wavelength absorption characteristics when water-soluble ink is used. In this embodiment, a carbon heater is used as the infrared heater, but a halogen heater may be used.
Further, the U-shaped infrared heater 15 shown in FIG. 4 is connected in a curved shape in the vicinity of the Y-axis guide member 10 and is at a position away from the Y-axis guide member 10 toward the downstream side in the media transport direction. Is formed. Thereby, the space | interval from the discharge nozzle 8a to the Y-axis guide member 10 which can shorten the space | interval of the Y-axis guide member 10 and the infrared heater 15 can be shortened.
Further, by using the U-shaped or annular infrared heater 15, the arrangement of the pair of power supply terminal portions 15 a is aligned in the same direction away from the downstream side in the media transport direction in a direction orthogonal to the Y-axis guide member 10. Since the space for wiring or the like of the infrared heater 15 to the carriage 9 (second frame 9b) can be secured, the assembly can be easily performed.

According to the above configuration, since the infrared heater 15 is provided on one end side in the scanning direction of the carriage 9, the ink droplet immediately after landing on the medium 4 can be dried by the infrared heater 15, thereby improving the drying efficiency. it can.
Further, since the infrared heater 15 has a curved shape in the vicinity of the Y-axis guide member 10 and a pair of power supply terminal portions 15 a formed at positions away from the Y-axis guide member 10, The interval with the heater 15 can be shortened. Accordingly, since the interval from the discharge nozzle 8a to the Y-axis guide member 10 can be shortened, the positional accuracy of the discharge nozzle 8a can be improved, and as a result, the print image quality can be improved.

  In FIG. 4, the infrared heater 15 is arranged to be shifted to the downstream side by a predetermined pitch from the upstream end of the nozzle row in the sub-scanning direction of the discharge nozzle 8 a in the medium conveyance direction. Specifically, the U-shaped curved top of the infrared heater 15 is shifted by one pitch conveyance from the upstream end in the medium conveyance direction of the nozzle row in the sub-scanning direction to the downstream side. Note that the shift amount of the infrared heater 15 toward the downstream side in the medium conveyance direction may be shifted by a plurality of pitches of the medium 4.

  As a result, it is possible to increase the drying efficiency by supplying the amount of heat necessary for drying according to the ejection amount of the ink droplets while realizing miniaturization of the infrared heater 15. In other words, the infrared heater 15 is shifted to relatively reduce the degree of drying at a printing portion where the amount of ink droplets ejected onto the medium 4 is small as in the recording operation of the first line in the carriage scanning direction, and the degree of drying is relatively weakened. While the infrared heater 15 is disposed at a printing portion where the amount of ink droplets discharged onto the medium 4 increases as in the recording operation after the first, the size of the infrared heater 15 is reduced by increasing the degree of drying relatively. Drying efficiency can be improved.

  In the recording operation of the first line, the amount of ink droplets ejected from the ejection head 8 is small, so that the ink droplets landed on the medium 4 by other drying means (heater, blower fan, etc.) even when the infrared heater 15 is stopped. Can be dried. In practice, it is better to dry the ink droplets ejected from the recording operation of the first line if possible. However, in order to surely dry the ink droplets that have landed on the medium 4 with a limited heat capacity while realizing a reduction in the size of the infrared heater 15, radiant heat due to more infrared irradiation on the ink discharge surface from the first line onward. This is because more efficient drying can be realized by concentrating the water.

Further, only one infrared heater 15 may be provided, but a plurality (for example, two) of infrared heaters 15 may be provided as shown in FIG. In this case, the two infrared heaters 15 may be arranged so as to be shifted in the sub-scanning direction by a predetermined pitch (for example, one pitch conveyance downstream in the medium conveyance direction). The shift amount between the infrared heaters 15 may be shifted by a plurality of pitches to the downstream side in the media conveyance direction.
Thereby, drying is performed with a relatively small amount of heat supplied from the infrared heater 15 at a printing location on the upstream side in the medium transport direction where the amount of ink droplets ejected onto the medium 4 is small, and ink on the downstream side in the media transport direction In a printing portion where the amount of ejected droplets has increased, the amount of heat supplied from the infrared heater 15 is relatively increased to perform drying, thereby supplying the necessary amount of heat according to the amount of ejected ink droplets ejected onto the media 4. It can be dried under optimum conditions.
In addition, by disposing a plurality of infrared heaters 15 in the sub-scanning direction, a wide dry area can be taken from the position where the ink droplets land on the medium 4 toward the downstream side in the media transport direction, so that the ink droplet fixing property can be obtained. However, the image quality can be improved.

  In FIG. 4, a reflector 20 is provided above the infrared heater 15 to reflect the radiant heat of the infrared heater 15 toward the medium 4. A plurality of through holes 20 a for heat dissipation are perforated in the reflector 20 at positions not directly above the infrared heater 15. The reflector 20 heated by the infrared heater 15 can be cooled by heat radiation through the through hole 20a.

  In FIG. 3, a blower fan 21 is provided above the reflector 20. When the blower fan 21 blows air through the through-hole 21a, the heat dissipating property of the reflector 20 is improved and the warm air is blown toward the medium 4 on which the ink droplets are discharged, so that the drying efficiency is improved.

Further, as shown in FIGS. 3 and 4, the infrared heater 15 is arranged so that one side thereof coincides with the upstream end of the ejection head 8 in the media conveyance direction or is shifted downstream from the upstream side, and the other side is further conveyed by the ejection head 8. It may be extended downstream from the direction downstream end.
As a result, the drying area by the infrared heater 15 can be widened with respect to the medium 4 from the position facing the ejection head 8 to the position where the ink droplets have already landed downstream from the ejection head 8 in the media transport direction. The fixing property to the toner is improved, and the image quality can be improved.

  Further, as shown in FIG. 5, the plurality of infrared heaters 15 provided are shifted by, for example, one pitch conveyance on the downstream side in the medium conveyance direction with respect to the upstream end of the discharge nozzle 8a in the medium conveyance direction. The infrared heaters 15 may be arranged such that the curved top portions that are curved in a U-shape do not shift in the media transport direction. This is because, for example, the infrared heaters 15 are selectively used in accordance with commercial power supply voltages (for example, 100 V to 120 V, 220 V to 240 V, etc.) that differ depending on the country or region.

  In FIG. 2, a cleaning device 19 is provided at a standby position that is one end of the scanning range of the carriage 10. The cleaning device 19 covers the ink ejection surface 8a of the ejection head 8 at the standby position in close contact with the head cap, and collects the ink sucked from the nozzles of each ink ejection surface 8a (see FIG. 3).

As shown in FIG. 3, the infrared heater 15 is provided so that the ejection head 8 is closer to the carriage 9 in the movement direction than the cleaning position facing the cleaning device 19. Thus, the infrared heater 15 does not cross directly above the cleaning device 19 when moving in the main scanning direction to the cleaning position 19 provided at one end of the scanning range of the carriage 9. Therefore, it is possible to prevent the cap surface of the head cap provided in the cleaning device 19 from drying.
In the present embodiment, as shown in FIG. 3, the infrared heater 15 is arranged on the left side of the first frame 9a of the carriage 9, but may be arranged on the right side of the first frame 9a. In this case, the cleaning device 19 may be arranged on the opposite side in the longitudinal direction of the Y-axis direction guide member 10 (the left end side in FIG. 2) from the present embodiment.

  DESCRIPTION OF SYMBOLS 1 Inkjet recording device 2 Feeding shaft 3 Feeding roll 4 Media 5 Upstream tension bar 6 Platen 7 Conveying device 8 Discharge head 8a Discharge nozzle 8b Head cover 9 Carriage 9a First frame 9b Second frame 9c, 20a Through hole 10 Y-axis direction guide Member 10a Guide rail 11 Tension roller 12 Downstream tension bar 13 Winding shaft 14 Winding roll 15 Infrared heater 15a Power supply terminal portion 16 Device body 17, 21 Blower fan 18 Ink cartridge 19 Cleaning device 20 Reflector

Claims (6)

Liquid discharge including a carriage mounted with a discharge head provided with discharge nozzles for discharging droplets to a recording medium and reciprocating along a guide portion formed on a guide member provided along the main scanning direction A device,
An infrared heater is provided on either end of the carriage in the main scanning direction to radiate infrared rays onto the droplets that have landed on the recording medium to dry the droplets, and the infrared heaters are connected in a curved shape near the guide member. A liquid ejecting apparatus, wherein a pair of power supply terminal portions are provided at positions away from the member in the sub-scanning direction.   The liquid ejection apparatus according to claim 1, wherein the infrared heater is arranged with a predetermined pitch shift downstream from an upstream end in a medium transport direction of a nozzle row in a sub-scanning direction provided in the ejection head.   The liquid ejecting apparatus according to claim 1, wherein a plurality of the infrared heaters are provided side by side and are shifted from each other by a predetermined pitch in the sub-scanning direction.   The infrared heater is arranged such that one side thereof coincides with or shifts downstream from the upstream end of the ejection head in the medium conveyance direction, and the other side extends further downstream from the downstream end of the ejection head in the medium conveyance direction. The liquid ejecting apparatus according to claim 1, wherein the liquid ejecting apparatus is a liquid ejecting apparatus.   5. The infrared heater according to claim 1, wherein the infrared heater is formed in a U-shape or an annular shape, and the pair of power feeding portions are arranged on the downstream side in the medium transport direction in a direction orthogonal to the guide member. The liquid discharge apparatus according to any one of the preceding claims. A liquid equipped with a carriage mounted with a discharge head provided with discharge nozzles for discharging droplets to a recording medium and reciprocating along a guide portion formed on a guide member provided along the main scanning direction A discharge device,
An infrared heater that radiates and drys the recording medium on either side of the carriage in the main scanning direction and an end of the scanning range of the carriage are arranged to clean the discharge nozzles of the discharge head. A cleaning device,
The liquid ejecting apparatus according to claim 1, wherein the infrared heater is provided so that the ejection head is located on the front side in the moving direction of the carriage from a cleaning position facing the cleaning apparatus.

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