JP2015066683A - Ink jet printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ink jet printer which can suppress useless radiation of ultraviolet ray and can suppress curing of ink before discharge in a recording head due to reception of ultraviolet ray.SOLUTION: A printer includes a guide rail 20 extending in a main scan direction Y, a recording head 40 which is slidably engaged with the guide rail 20 and discharges UV curable ink to a recording medium 5, and ultraviolet irradiation devices 51 and 52. The ultraviolet irradiation device 51 and 52 each includes a case 53 provided with an irradiation port, and a light source 54 which is disposed in the case 53 and radiates ultraviolet ray, and is so provided as to move together with the recording head 40 with respect to the recording head 40. The ultraviolet irradiation devices 51 and 52 are each provided with diffusion prevention means 57 which prevents diffusion in the main scan direction of ultraviolet ray which is radiated from the light source 54 to the recording medium 5.

Description

  The present invention relates to an inkjet printer.

  2. Description of the Related Art Conventionally, ink jet printers that use ink that is cured when irradiated with ultraviolet rays (hereinafter referred to as ultraviolet curable ink) are known as ink ejected from a nozzle of a recording head to a recording medium (see, for example, Patent Document 1). ).

  Inkjet printers that use ultraviolet curable ink include an apparatus that irradiates ultraviolet light (hereinafter referred to as an ultraviolet irradiation apparatus) in order to cure the ink ejected from the recording head on the recording medium. As this ultraviolet irradiation device, one that is attached to a recording head and moves integrally with the recording head is known.

Japanese Patent No. 4142345

  By the way, in the ink jet printer disclosed in Patent Document 1, ultraviolet rays are irradiated downward from the ultraviolet irradiation device, but at that time, the ultraviolet rays may spread in the front-rear direction and the left-right direction. The spread ultraviolet rays may be irradiated to unnecessary portions of the recording medium where ink is not ejected, which may cause energy loss of the ultraviolet irradiation device. Further, there is a possibility that the spread ultraviolet rays are reflected on the recording medium or the like, and the reflected ultraviolet rays are irradiated to the recording head. As a result, the ink in the nozzles of the recording head may be irradiated and cured before ejection, leading to ejection failure and nozzle clogging.

  The present invention has been made in view of the above points, and an object thereof is to include a recording head that discharges ultraviolet curable ink onto a recording medium, and an ultraviolet irradiation device that irradiates the ink discharged onto the recording medium with ultraviolet light. Another object of the present invention is to provide an ink jet printer that can prevent wasteful irradiation of ultraviolet rays and can suppress ejection failure and nozzle clogging due to curing of ink before ejection.

  An ink jet printer according to the present invention includes a guide rail extending in a main scanning direction, and a recording head that slidably engages with the guide rail so as to be movable in the main scanning direction and discharges ultraviolet curable ink toward a recording medium. And a case in which an irradiation port is formed, and a light source that is arranged inside the case and that irradiates ultraviolet rays, and is provided so as to move with the recording head relative to the recording head. And an ultraviolet irradiation device that irradiates the ultraviolet curable ink discharged onto the recording medium with ultraviolet rays. The ultraviolet irradiation device is provided with diffusion preventing means for preventing the ultraviolet rays irradiated from the light source toward the recording medium from spreading in the main scanning direction.

  According to the ink jet printer, the spread in the main scanning direction of the ultraviolet rays irradiated from the light source toward the recording medium can be prevented by the diffusion preventing means provided in the ultraviolet irradiation device. For this reason, it is possible to irradiate ultraviolet rays intensively on a necessary portion of the recording medium, and to prevent unnecessary irradiation of ultraviolet rays. Further, it is possible to prevent the irradiated ultraviolet rays from being reflected by the recording medium and the reflected ultraviolet rays from being irradiated to the recording head. Therefore, it is unlikely that ultraviolet rays are irradiated to the ink before ejection in the nozzles of the recording head, and ejection failure and nozzle clogging due to curing of the ink before ejection can be suppressed.

  According to a preferred aspect of the present invention, the diffusion preventing means is a lens attached to the ultraviolet irradiation device so as to cover the irradiation port.

  According to the said aspect, since the lens is attached so that an irradiation port may be covered, the spreading of the ultraviolet-ray irradiated from an irradiation port can be prevented reliably.

  According to another preferred aspect of the present invention, the lens is a condenser lens.

  According to the said aspect, since the ultraviolet-ray irradiated from a light source is condensed with a lens, it can prevent the said ultraviolet-ray spreading.

  According to another preferred aspect of the present invention, the lens is a cylindrical lens.

  According to the said aspect, it can prevent with the simpler structure that the ultraviolet-ray irradiated from a light source spreads.

  According to another preferred aspect of the present invention, the lens is a Fresnel lens.

  According to the said aspect, it can prevent with the simpler structure that the ultraviolet-ray irradiated from a light source spreads.

  According to another preferable aspect of the present invention, the length in the main scanning direction of the irradiation range in which the ultraviolet ray irradiated from the light source is irradiated on the recording medium is the length of the irradiation port in the main scanning direction. It is 2.0 times or less.

  By setting the relationship between the length in the main scanning direction of the irradiation range of the ultraviolet rays irradiated to the recording medium and the length of the irradiation port in the main scanning direction as described above, the ultraviolet rays reflected from the recording medium are transferred to the ink in the recording head. Can be made difficult to irradiate.

  According to another preferable aspect of the present invention, the irradiation intensity of 10% or more of the maximum irradiation intensity on the recording medium is within the irradiation range in which the ultraviolet ray irradiated from the light source is irradiated on the recording medium. The length of the irradiation range irradiated with ultraviolet rays in the main scanning direction is 1.2 times or less the length of the irradiation port in the main scanning direction.

  According to the above aspect, the relationship between the length in the main scanning direction of the irradiation range irradiated with ultraviolet rays at an irradiation intensity of 10% or more of the maximum irradiation intensity on the recording medium and the length in the main scanning direction of the irradiation port is described above. By doing so, it is possible to make it more difficult to irradiate the ultraviolet rays reflected from the recording medium with the ink in the recording head.

  According to the present invention, it is possible to provide an ink jet printer that can prevent wasteful irradiation of ultraviolet rays and can suppress ejection failure and nozzle clogging due to curing of ink before ejection.

It is a perspective view of a printer. 2 is a plan view showing an internal configuration of the printer. FIG. 2 is a plan view of a recording head and its surroundings. FIG. It is a front view of a recording head and its periphery. It is a graph which shows the irradiation intensity | strength of the ultraviolet-ray in each position along the left-right direction from the center of an irradiation port. It is front sectional drawing of a lens and its periphery. It is side surface sectional drawing of a lens and its periphery. It is front sectional drawing of the lens which concerns on other embodiment, and its periphery.

  Hereinafter, an ink jet printer (hereinafter referred to as a printer) according to an embodiment of the present invention will be described. The embodiments described herein are, of course, not intended to limit the present invention in particular. Further, members / parts having the same action are denoted by the same reference numerals, and redundant description is omitted or simplified.

  FIG. 1 is a perspective view of a printer 1 according to the present embodiment. FIG. 2 is a plan view showing the internal configuration of the printer 1. In the following drawings, symbols F, Rr, L, and R indicate front, rear, left, and right, respectively. However, these are only directions for convenience of explanation, and do not limit the installation mode of the printer 1 at all. Symbol Y indicates the main scanning direction. The main scanning direction Y is an example of a predetermined direction in which a guide rail 20 described later extends. A symbol X indicates a sub-scanning direction perpendicular to the main scanning direction Y. However, the main scanning direction Y and the sub-scanning direction X are not particularly limited, and can be appropriately set according to the form of the printer 1 and the like.

  As shown in FIG. 1, the printer 1 performs printing on a recording paper 5. The recording paper 5 is an example of a recording medium. The recording paper 5 is a roll-shaped recording medium, so-called roll paper. However, the recording medium of the present invention is not limited to the recording paper 5. For example, the recording medium may be a resin sheet. The recording medium is not limited to a flexible sheet, and may be a hard recording medium such as a glass substrate.

  In the present embodiment, the printer 1 includes a printer main body 10 having a casing 10 </ b> A extending in the main scanning direction Y, and legs 11 that support the printer main body 10. An operation panel 12 is provided on the right side of the printer main body 10.

  Although not shown, the operation panel 12 includes a display unit for displaying information related to printing such as monochrome printing or color printing, resolution, and ink density, and an input unit for inputting the information. Yes.

  A front cover 15 that can be freely opened and closed is attached to an upper portion of the printer body 10. A discharge port 13 for discharging the recording paper 5 is formed below the printer main body 10. A guide 14 is provided at a position in front of and below the discharge port 13 to guide the recording paper 5 discharged from the discharge port 13 obliquely forward and downward.

  Next, the internal configuration of the printer body 10 will be described. As shown in FIG. 2, the printer 1 includes a guide rail 20. The guide rail 20 is provided inside the printer main body 10. The guide rail 20 extends in the main scanning direction Y. A platen 25 is disposed in front of the central portion of the guide rail 20. The platen 25 extends in the main scanning direction Y. The platen 25 supports the recording paper 5 when printing on the recording paper 5. Printing on the recording paper 5 is performed on the platen 25.

  A pulley 21 is provided in the vicinity of the right end portion of the guide rail 20. A pulley 22 is provided in the vicinity of the left end portion of the guide rail 20. An endless belt 23 is wound around the pulley 21 and the pulley 22. A servo motor 24 is connected to the pulley 21. When the servo motor 24 drives the pulley 21, the belt 23 travels between the pulley 21 and the pulley 22. A control device 35 is communicably connected to the servo motor 24. The servo motor 24 is a motor that can rotate forward and backward. The control device 35 controls the movement of the carriage 30 described later by controlling the servo motor 24. In this embodiment, the pulley 21 is driven, but the pulley 22 may be driven. In this case, a servo motor 24 is connected to the pulley 22.

  A carriage 30 is attached to the belt 23. Although not shown, the carriage 30 is engaged with the guide rail 20. Therefore, the carriage 30 moves in the main scanning direction Y along the guide rail 20 as the belt 23 travels.

  A pair of upper and lower rollers 26 (only the upper roller 26 is shown in FIG. 2) for feeding the recording paper 5 in the sub-scanning direction X are disposed at the left end and the right end of the platen 25, respectively. However, the installation positions of the pair of upper and lower rollers 26 are not limited to the left end portion and the right end portion of the platen 25. One of the pair of upper and lower rollers 26 is a driving roller that rotates by itself, and the other roller 26 is a pinch roller for sandwiching the recording paper 5 together with the driving roller. In addition, although illustration is abbreviate | omitted, the control apparatus 35 is connected to the drive roller among the rollers 26 so that communication is possible. The operation of the driving roller is controlled by the control device 35.

  In the present embodiment, the printer 1 includes a recording head 40, a first ultraviolet irradiation device 51, and a second ultraviolet irradiation device 52. The recording head 40 is a head that ejects ink toward the recording paper 5. This ink is an ink that is cured when irradiated with ultraviolet rays, that is, an ultraviolet curable ink. The recording head 40 is slidably engaged with the guide rail 20. In the present embodiment, the recording head 40 is attached to the carriage 30. The recording head 40 is slidably engaged with the guide rail 20 via the carriage 30.

  FIG. 3 is a plan view of the recording head 40 and its periphery. FIG. 4 is a front view of the recording head 40 and its surroundings. As shown in FIG. 3, the recording head 40 includes a plurality of print heads 41 and a print head carriage 42. The print head 41 has a nozzle (not shown) that ejects ink. The print head 41 ejects ink downward from the nozzles. Although not shown, an ink cartridge (not shown) filled with ink is attached to the rear portion of the printer body 10. The print head 41 is connected to the ink cartridge via a tube (not shown). Ink is supplied to the print head 41 from the ink cartridge. Although not shown, the control device 35 is communicably connected to the print head 41. The ejection operation of the print head 41 is controlled by the control device 35. The print head carriage 42 supports a plurality of print heads 41. The print head carriage 42 is engaged with the guide rail 20 so as to be movable in the left-right direction.

  The first ultraviolet irradiation device 51 and the second ultraviolet irradiation device 52 are devices that irradiate the ultraviolet curable ink discharged onto the recording paper 5 with ultraviolet rays. In the present embodiment, the ultraviolet irradiation devices 51 and 52 include ultraviolet light emitting diodes as light sources. However, the light sources of the ultraviolet irradiation devices 51 and 52 are not limited to the ultraviolet light emitting diodes as long as they emit ultraviolet rays. For example, the ultraviolet irradiation devices 51 and 52 may include a halogen lamp as a light source.

  The ultraviolet irradiation devices 51 and 52 are provided so as to move with the recording head 40 relative to the recording head 40. The ultraviolet irradiation devices 51 and 52 are provided on the Y side of the recording head 40 in the main scanning direction, that is, on both the left and right sides. In the present embodiment, the first ultraviolet irradiation device 51 is attached to the left side of the print head carriage 42 via the connecting member 43. The second ultraviolet irradiation device 52 is attached to the right side of the print head carriage 42 via the connecting member 44. The 1st ultraviolet irradiation device 51 and the 2nd ultraviolet irradiation device 52 are arrange | positioned in the position which mutually shifted | deviated to the front-back direction. Here, the first ultraviolet irradiation device 51 is disposed behind the second ultraviolet irradiation device 52. However, the first ultraviolet irradiation device 51 may be disposed in front of the second ultraviolet irradiation device 52. Moreover, the position of the front-back direction of the 1st ultraviolet irradiation device 51 and the 2nd ultraviolet irradiation device 52 may be the same.

  As shown in FIG. 4, the first ultraviolet irradiation device 51 includes a case 53, a plurality of ultraviolet light emitting diodes (hereinafter referred to as light emitting elements) 54 disposed inside the case 53, a cable 55, and an irradiation port 56 ( 3) and a lens 57. The plurality of light emitting elements 54 irradiate ultraviolet rays. The light emitting element 54 is accommodated in the case 53. The cable 55 is connected to the light emitting element 54 and a power source (not shown). The cable 55 supplies electricity to the light emitting element 54.

  As shown in FIG. 3, the irradiation port 56 is a part that irradiates the ultraviolet curable ink discharged from the recording head 40 onto the recording paper 5 with ultraviolet rays. In the present embodiment, the irradiation port 56 is formed on the bottom surface of the case 53. The ultraviolet light emitted from the light emitting element 54 is irradiated to the recording paper 5 through the irradiation port 56. The irradiation port 56 has a quadrangular shape. However, the shape of the irradiation port 56 is not specifically limited, For example, circular shape may be sufficient.

  By the way, in the conventional printer, the spread of the ultraviolet rays emitted from the light emitting elements of the ultraviolet irradiation device is determined by the light distribution of the light emitting elements. FIG. 5 is a graph showing the irradiation intensity of ultraviolet rays at each position (each position on the recording paper 5) along the left-right direction (main scanning direction) from the center of the irradiation port 56. Reference numeral A indicates an ultraviolet irradiation intensity distribution of an ultraviolet irradiation device in a conventional printer (a printer that does not include a diffusion prevention unit such as a lens 57 described later). Reference symbol B indicates the irradiation intensity distribution of the ultraviolet rays of the ultraviolet irradiation devices 51 and 52 in the printer 1 of this embodiment (a printer provided with a diffusion prevention unit such as the lens 57). FIG. 5 shows a state where the length from the center to the periphery of the irradiation port 56 is about 10 mm. For example, as shown by reference symbol A in FIG. 5, in the case of a conventional printer, the ultraviolet rays from the light emitting elements spread outward from the irradiation port according to the light distribution of the light emitting elements. In the conventional printer, the irradiation intensity distribution of the ultraviolet irradiation device is substantially the same as the light distribution of the light emitting elements. In particular, ultraviolet rays are irradiated even at a position about 10 mm or longer from the center of the irradiation port. As described above, the ultraviolet irradiation range is widened, and if the recording paper 5 is irradiated with the ultraviolet rays obliquely, the recording head 40 may be irradiated with the reflected ultraviolet rays. If the recording head 40 is irradiated with the reflected ultraviolet light, the ink in the nozzle (not shown) of the recording head 40 may be cured. Then, since the ink is cured, the nozzles of the recording head 40 are clogged, and there is a possibility that desired printing cannot be performed.

  However, in the present embodiment, the first ultraviolet irradiation device 51 of the printer 1 includes the lens 57. The lens 57 is a lens that prevents the spread of ultraviolet rays irradiated from the irradiation port 56 toward the recording paper 5. The light distribution of the light emitting elements is the same as that of a conventional printer, but the lens 57 suppresses the spread of the illuminance intensity distribution of the first ultraviolet irradiation device 51. The lens 57 corresponds to diffusion preventing means. FIG. 6 is a front sectional view of the lens 57 and its periphery. FIG. 7 is a side sectional view of the lens 57 and its periphery. In FIGS. 6 and 7, the arrows indicate ultraviolet rays. 6 indicates the center of the first ultraviolet irradiation device 51 (the center of the light source element 54), and this center C corresponds to the position “0” of the irradiation intensity distribution in FIG. As shown in FIG. 6, the lens 57 condenses the ultraviolet light emitted from the light emitting element 54. Here, the lens 57 is constituted by a cylindrical lens. The cylindrical lens is conventionally known, and one surface 57b has a curved surface protruding in a columnar shape, and the other surface 57a opposite to the one surface 57b has a flat surface. In the lens 57, one surface 57b may be a flat surface and the other surface 57a may be a curved surface protruding in a columnar shape. In addition, the cylindrical lens has a cross section 57c (see FIG. 6) in which a part of the periphery is curved, and a cross section 57d (see FIG. 7) that is orthogonal to the cross section and in which all the periphery is a straight line.

  A lens 57 formed of a cylindrical lens is disposed between the irradiation port 56 formed in the case 53 and the recording paper 5. In other words, the lens 57 is disposed between the light emitting element 54 and the recording paper 5. In the present embodiment, the lens 57 is attached to the bottom surface of the case 53 so as to cover the irradiation port 56. Specifically, the lens 57 is arranged on the bottom surface of the case 53 so that one of the curved surfaces 57b of the lens 57 is directed downward and a cross section 57c having a curved portion at the periphery extends in the main scanning direction. ing. The length from the lens 57 to the recording paper 5 is not particularly limited.

  As shown in FIG. 6, the ultraviolet rays are refracted on the surface along the cross section 57 c (the surface orthogonal to the sub-scanning direction X). Ultraviolet rays are refracted toward the center side. Therefore, as indicated by reference numeral B in FIG. 5, the ultraviolet rays from the irradiation port 56 do not spread so much outside the periphery of the irradiation port 56 in the main scanning direction Y. Further, as shown in FIG. 6, the length L1 in the main scanning direction Y in the range where the recording paper 5 is irradiated with ultraviolet rays is 2.0 times or less the length L2 of the irradiation port 56 in the main scanning direction Y. . For example, in the present embodiment, the length L1 is 28 mm and the length L2 is 20 mm. In FIG. 5, a symbol L <b> 3 is a length in the main scanning direction Y of an irradiation range irradiated with ultraviolet rays at an irradiation intensity H <b> 1 that is 10% of the maximum irradiation intensity H on the recording medium 5. As shown in FIG. 5, the length L3 is 1.2 times or less of the length L2 of the irradiation port 56 in the main scanning direction Y. Specifically, the irradiation intensity of the ultraviolet irradiation device 51 becomes weaker as the distance from the center C of the ultraviolet irradiation device 51 in the main scanning direction Y increases. The length L3 in the main scanning direction Y of the irradiation range irradiated with ultraviolet rays at an irradiation intensity of 10% or more of the maximum irradiation intensity H on the recording medium 5 is 1. 2 times or less. For example, in the present embodiment, the length L3 is 21 mm. However, the lengths L1, L2, and L3 are not particularly limited as long as the lengths are as described above. On the other hand, as shown in FIG. 7, on the surface along the cross-section 57d (the surface orthogonal to the main scanning direction Y), the ultraviolet rays spread outward without being refracted.

  In addition, although illustration is abbreviate | omitted, the control apparatus 35 is connected to the 1st ultraviolet irradiation device 51 so that communication is possible. The light emission operation of the first ultraviolet irradiation device 51 is controlled by the control device 35. The configuration of the second ultraviolet irradiation device 52 is the same as the configuration of the first ultraviolet irradiation device 51. Therefore, detailed description of the second ultraviolet irradiation device 52 is omitted.

  During printing, the recording head 40 ejects ink onto the recording paper 5 while moving in the main scanning direction Y along the guide rail 20. At this time, the ultraviolet irradiation devices 51 and 52 arranged on the side of the recording head 40 move in the main scanning direction Y together with the recording head 40. In the present embodiment, when moving from left to right among the movements in the main scanning direction Y, the ink ejected to the recording paper 5 by the recording head 40 is cured by the ultraviolet rays irradiated by the first ultraviolet irradiation device 51. Is done. On the other hand, when moving from the right to the left in the movement in the main scanning direction Y, the ink ejected to the recording paper 5 by the recording head 40 is cured by the ultraviolet rays irradiated by the second ultraviolet irradiation device 52. The above is merely an example of the operation of the ultraviolet irradiation devices 51 and 52, and the operation timing of the ultraviolet irradiation devices 51 and 52 is not particularly limited. In the present embodiment, as shown in FIG. 6, the ultraviolet rays irradiated from the optical elements 54 of the ultraviolet irradiation devices 51 and 52 do not spread in the main scanning direction Y by the lens 57. For this reason, the ink ejected onto the recording paper 5 is cured by the ultraviolet rays when passing under the ultraviolet irradiation device 51 or 52.

  As described above, in the present embodiment, the ultraviolet irradiation devices 51 and 52 are each provided with the lens 57 that prevents the ultraviolet rays irradiated from the optical element 54 toward the recording paper 5 from spreading. As a result, compared with a conventional printer in which the lens 57 is not provided in the ultraviolet irradiation device, it is possible to prevent the ultraviolet rays from spreading (in this embodiment, particularly in the main scanning direction Y). Therefore, useless irradiation of ultraviolet rays can be prevented. The ultraviolet irradiation devices 51 and 52 can save energy. Further, the ultraviolet irradiation devices 51 and 52 can be reduced in size or weight. Further, according to the present embodiment, the ultraviolet light emitted from the irradiation port 56 is reflected by the recording paper 5, and the reflected ultraviolet light can be hardly irradiated to the recording head 40. Accordingly, it is possible to suppress the ink in the recording head 40 from being cured before being discharged due to the ultraviolet rays reflected by the recording paper 5. Therefore, ejection failure of the recording head 40 and nozzle clogging can be suppressed.

  In the present embodiment, the ultraviolet rays irradiated from the irradiation port 56 are irradiated from the top to the bottom toward the recording paper 5. The lens 57 is disposed between the irradiation port 56 and the recording paper 5 and is disposed in each of the ultraviolet irradiation devices 51 and 52 so as to cover the irradiation port 56. Since the lens 57 is attached so as to cover the irradiation port 56, it is possible to reliably prevent the spread of ultraviolet rays irradiated from the irradiation port 56.

  In the present embodiment, the lens 57 is a lens that collects ultraviolet rays from the irradiation port 56. The lens 57 is configured by a cylindrical lens. Accordingly, it is possible to prevent the ultraviolet rays from spreading (particularly in the main scanning direction Y) with a simple configuration.

  In the present embodiment, as shown in FIG. 6, the length L1 in the main scanning direction Y of the ultraviolet irradiation range on the recording paper 5 is 2.0 times or less the length L2 of the irradiation port 56 in the main scanning direction Y. It is. Further, as shown in FIG. 5, the length in the main scanning direction Y of the irradiation range irradiated with ultraviolet rays at an irradiation intensity of 10% or more of the maximum irradiation intensity H on the recording medium 5 is the main scanning direction of the irradiation port 56. It is 1.2 times or less the length L2 of Y. Thereby, the ultraviolet rays reflected by the recording paper 5 can be made difficult to irradiate the ink in the recording head 40.

  The embodiment of the present invention has been described above. However, the above-described embodiment is merely an example, and the present invention can be implemented in various other forms.

  The lens 57 is not limited to a cylindrical lens. For example, the lens 57 may be composed of a Fresnel lens as shown in FIG. The Fresnel lens has a sawtooth shape on one surface. The Fresnel lens can also collect ultraviolet rays. In particular, by providing the lens 57 composed of a Fresnel lens in each of the cases 53 of the ultraviolet irradiation devices 51 and 52, not only the ultraviolet rays are prevented from spreading in the main scanning direction Y, but also spread in the sub-scanning direction X. Can be prevented.

  In the above embodiment, the lens 57 is attached to the bottom surface of each case 53 of the ultraviolet irradiation devices 51 and 52. However, the mounting position of the lens 57 is not particularly limited as long as it can prevent the ultraviolet rays irradiated from the light source 54 toward the recording paper 5 from spreading. For example, the lens 57 may be attached to the print head carriage 42 so as to extend directly from the print head carriage 42 of the recording head 40 to the irradiation ports 56 of the ultraviolet irradiation devices 51 and 52. In the embodiment described above, the lens 57 is disposed outside the case 53, but the lens 57 may be disposed inside the case 53. For example, the lens 57 may be disposed inside the case 53 and above the irradiation port 56.

  In the above embodiment, the diffusion preventing means is the lens 57. However, the diffusion preventing means of the present invention is provided in the light emitting element (light source) 54 that emits ultraviolet light, and the light distribution of the light emitting element 54 is a desired irradiation intensity distribution as indicated by reference numeral B in FIG. You may make it become.

  In the above embodiment, the first ultraviolet irradiation device 51 is provided on the left side of the recording head 40, and the second ultraviolet irradiation device 52 is provided on the right side of the recording head 40. However, one ultraviolet irradiation device may be provided on the left side or the right side of the recording head 40. That is, it is possible to omit either the first ultraviolet irradiation device 51 or the second ultraviolet irradiation device 52.

  In the above embodiment, the ultraviolet irradiation devices 51 and 52 are guided by the guide rail 20 via the recording head 40 and moved in the main scanning direction Y. However, the ultraviolet irradiation devices 51 and 52 themselves may be configured to be independently guided by the guide rail 20.

1 Printer (inkjet printer)
5 Recording paper (recording medium)
20 Guide rail 40 Recording head 51 First ultraviolet irradiation device (ultraviolet irradiation device)
52 Second ultraviolet irradiation device (ultraviolet irradiation device)
53 Case 54 Light Emitting Element (Light Source)
55 Cable 56 Irradiation port 57 Lens (Diffusion prevention means)

Claims (7)

A guide rail extending in the main scanning direction;
A recording head that slidably engages with the guide rail so as to be movable in the main scanning direction, and discharges ultraviolet curable ink toward the recording medium;
A case in which an irradiation port is formed; a light source that is disposed inside the case and that emits ultraviolet rays; and is provided so as to move with the recording head relative to the recording head, from the recording head to the recording medium An ultraviolet irradiation device that irradiates the ultraviolet curable ink discharged to the ultraviolet ray;
With
An ink jet printer, wherein the ultraviolet irradiation device is provided with a diffusion preventing means for preventing the ultraviolet rays irradiated from the light source toward the recording medium in the main scanning direction.   The inkjet printer according to claim 1, wherein the diffusion preventing unit is a lens attached to the ultraviolet irradiation device so as to cover the irradiation port.   The inkjet printer according to claim 2, wherein the lens is a condenser lens.   The inkjet printer according to claim 2, wherein the lens is a cylindrical lens.   The inkjet printer according to claim 2, wherein the lens is a Fresnel lens.   The length in the main scanning direction of an irradiation range in which ultraviolet rays irradiated from the light source are irradiated on the recording medium is 2.0 times or less of a length of the irradiation port in the main scanning direction. The inkjet printer described in any one of 1-5.   The main scanning direction of the irradiation range irradiated with the ultraviolet rays at an irradiation intensity of 10% or more of the maximum irradiation intensity on the recording medium among the irradiation ranges irradiated with the ultraviolet rays from the light source. 7. The inkjet printer according to claim 1, wherein a length of the irradiation port is 1.2 times or less of a length of the irradiation port in the main scanning direction.

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