Active energy irradiation device

Abstract

To provide active energy irradiation equipment enabling suppression of mixing of oxygen into a region between an irradiated object and an active energy irradiation unit.SOLUTION: Active energy ray irradiation equipment 1 comprises: an active energy irradiation unit 3 having an emission surface 30 that expands in both directions of X-direction and Y-direction and emits UV-rays to one side in a Z direction; an inert gas supply unit 8 having a jetting port 83 located on one side in a Y direction relative to the emission surface 30 and jetting inert gas to one side in the Z direction; and an inert gas suction unit 9 having a protrusion portion 90 located on the other side in the Y direction relative to the emission surface 30 and protruding to one side in the Z direction relative to the emission surface 30. A width 90y of the protruding portion 90 in the Y direction is larger than a width 90z of the protrusion portion 90 in the Z direction.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to an active energy irradiation device. [Background technology]

[0002] There is known an active energy irradiation device that includes an active energy irradiation unit that irradiates an object to be irradiated with active energy rays, and an inert gas supply unit that supplies an inert gas to a region between the object to be irradiated and the active energy irradiation unit (see, for example, Patent Document 1). In such an active energy irradiation device, inert gas is supplied to a region between the object to be irradiated and the active energy irradiation unit in order to prevent oxygen in the air from inhibiting the action caused in the object to be irradiated by the irradiation of active energy rays. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2017 / 170949 Summary of the Invention [Problem to be solved by the invention]

[0004] In the active energy irradiation device as described above, for example, if the transport speed of the irradiated object relative to the active energy irradiation section increases, oxygen is more likely to be mixed into the area between the irradiated object and the active energy irradiation section, and the action occurring in the irradiated object due to the irradiation of active energy rays may be inhibited by oxygen.

[0005] An object of the present invention is to provide an active energy irradiation device capable of suppressing oxygen from entering the region between an object to be irradiated and an active energy irradiation unit. [Means for solving the problem]

[0006] The active energy irradiation device of the present invention comprises an active energy irradiation section having an exit surface extending in both a first direction and a second direction perpendicular to the first direction, and emitting active energy rays to one side of a third direction perpendicular to both the first direction and the second direction; an inert gas supply section having an outlet located on one side of the exit surface in the second direction, and having an outlet for ejecting inert gas to one side of the third direction; and a structure including a protruding portion located on the other side of the exit surface in the second direction, and protruding to one side of the third direction from the exit surface, wherein the width of the protruding portion in the second direction is greater than the width of the protruding portion in the third direction.

[0007] In this active energy irradiation device, when the irradiated object is transported from one side in the second direction to the other side in the second direction relative to the exit surface of the active energy irradiation unit, the inert gas ejected from the ejection port of the inert gas supply unit is supplied to the region between the irradiated object and the active energy irradiation unit. At this time, a protruding portion whose width in the second direction is larger than its width in the third direction is located on the other side in the second direction relative to the exit surface of the active energy irradiation unit, making it difficult for the inert gas to flow out from the region between the irradiated object and the active energy irradiation unit to the downstream side in the transport direction of the irradiated object (the other side in the second direction). Therefore, this active energy irradiation device makes it possible to suppress oxygen from entering the region between the irradiated object and the active energy irradiation unit.

[0008] In the active energy irradiation device according to the present invention, the inert gas supply unit may include a jetting portion provided with a jetting port and protruding toward one side in the third direction from the exit surface. This makes it difficult for air to flow into the region between the irradiated object and the active energy irradiation unit from the upstream side in the transport direction of the irradiated object (one side in the second direction). Therefore, it is possible to more reliably suppress the intrusion of oxygen into the region between the irradiated object and the active energy irradiation unit.

[0009] In the active energy irradiation device according to the present invention, the width of the jetting portion in the third direction may be greater than the width of the protruding portion in the third direction. This brings the jetting port of the inert gas supply unit closer to the irradiated object, making it difficult for air to flow from the upstream side in the transport direction of the irradiated object into the region between the irradiated object and the active energy irradiation unit. This makes it possible to more reliably prevent oxygen from being mixed into the region between the irradiated object and the active energy irradiation unit.

[0010] The active energy irradiation device according to the present invention further includes a support that supports the active energy irradiation unit, the inert gas supply unit, and the structure, and the width of the active energy irradiation unit in the first direction, the width of the inert gas supply unit in the first direction, and the width of the structure in the first direction may each be equal to or less than the width of the support in the first direction. This allows a plurality of active energy irradiation devices to be arranged so that the supports are in contact with each other in the first direction, making it possible to accommodate an irradiated object that is wide in the first direction.

[0011] In the active energy irradiation device according to the present invention, the width of the outlet in the first direction and the width of the protruding portion in the first direction may each be equal to the width of the emission surface in the first direction. This makes it possible to uniformly irradiate an irradiated object having a wide width in the first direction with active energy rays while suppressing oxygen from entering a region between the irradiated object and the multiple active energy irradiation units in a plurality of active energy irradiation devices arranged so that the supports are in contact with each other in the first direction.

[0012] In the active energy irradiation device according to the present invention, the structure may be detachably attached to the support, which makes it easy to replace and maintain the structure.

[0013] In the active energy irradiation device according to the present invention, at least the protruding portion may have a surface that absorbs active energy rays, thereby preventing the active energy rays from being reflected by the protruding portion and being irradiated onto unwanted locations.

[0014] In the active energy irradiation device according to the present invention, the structure may include a box or a block, which can prevent the inert gas from flowing out from the region between the irradiated object and the active energy irradiation unit to the downstream side in the transport direction of the irradiated object.

[0015] In the active energy irradiation device according to the present invention, the structure may include a plurality of plates, which makes it possible to suppress outflow of the inert gas from the region between the irradiated object and the active energy irradiation unit to the downstream side in the transport direction of the irradiated object.

[0016] In the active energy irradiation device according to the present invention, the structure may have a suction port for sucking in the inert gas, thereby making it possible to efficiently collect the inert gas supplied to the region between the irradiated object and the active energy irradiation unit.

[0017] The active energy irradiation device according to the present invention may further include a pair of shielding plates disposed on one side and the other side of the exit surface in the first direction. This makes it difficult for the inert gas to flow out from the region between the irradiated object and the active energy irradiation unit to the one side and the other side in the first direction. Therefore, it is possible to more reliably suppress oxygen from entering the region between the irradiated object and the active energy irradiation unit.

[0018] In the active energy irradiation device according to the present invention, the active energy irradiation unit may emit ultraviolet rays or electron beams as the active energy rays, thereby allowing the active energy irradiation device to be used as a device for irradiating an object with ultraviolet rays or electron beams. [Effects of the Invention]

[0019] According to the present invention, it is possible to provide an active energy irradiation device capable of suppressing oxygen from entering the region between the object to be irradiated and the active energy irradiation unit. [Brief explanation of the drawings]

[0020] [Figure 1]FIG. 1 is a perspective view of an active energy irradiation system according to one embodiment. [Figure 2] FIG. 2 is a perspective view of the active energy irradiation device shown in FIG. [Figure 3] FIG. 3 is a perspective view of the active energy irradiation device shown in FIG. 2 as seen from below. [Figure 4] FIG. 4 is an exploded perspective view of the active energy irradiation device shown in FIG. [Figure 5] 5 is a perspective view showing the internal configuration of the housing of the active energy irradiation device shown in FIG. [Figure 6] FIG. 6 is a front view showing the air flow in the active energy irradiation device shown in FIG. [Figure 7] FIG. 7 is a cross-sectional view of the active energy irradiation device taken along the line AA shown in FIG. [Figure 8] FIG. 8 is an end view of the active energy irradiation device taken along line BB shown in FIG. [Figure 9] 9 is a cross-sectional view of an inert gas supply unit of the active energy irradiation device shown in FIG. [Figure 10] FIG. 10 is a cross-sectional view of a portion of the active energy irradiation device shown in FIG. [Figure 11] FIG. 11 shows the experimental results. [Figure 12] FIG. 12 shows the experimental results. [Figure 13] FIG. 13 is a perspective view of a modified structure. [Figure 14] FIG. 14 is a perspective view of a modified active energy irradiating device as viewed from below. DETAILED DESCRIPTION OF THE INVENTION

[0021] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In each drawing, the same or corresponding parts are designated by the same reference numerals, and redundant explanations will be omitted.

[0022] As shown in FIG. 1, the active energy irradiation system 100 is a system mounted on, for example, a UV (ultraviolet) printer, and includes multiple active energy irradiation devices 1. The active energy irradiation devices 1 are, for example, high-output air-cooled LED light sources for printing applications. The active energy irradiation devices 1 irradiate an object with ultraviolet rays (active energy rays) to dry ink on the object, for example. The object to be irradiated may be, for example, a printed material with photocurable ink attached.

[0023] The active energy irradiation device 1 has a rectangular parallelepiped outer shape. The active energy irradiation devices 1 are arranged so as to abut against each other in a predetermined direction. The multiple active energy irradiation devices 1 arranged in the predetermined direction are fixed and held by a fixing plate 11. In the illustrated example, the active energy irradiation system 100 includes a unit consisting of multiple active energy irradiation devices 1 fixed to the fixing plate 11. As shown in Figures 2, 3, 4, and 5, the active energy irradiation device 1 includes a housing (support) 2, an active energy irradiation section 3, a heat sink 4, an intake section 5, an exhaust section 6, a duct 7, an inert gas supply section 8, and an inert gas suction section (structure) 9.

[0024] For ease of explanation, the predetermined direction in which the multiple active energy irradiation devices 1 are lined up is referred to as the "X direction" (first direction), the direction in which ultraviolet rays are emitted by the active energy irradiation device 1 and which is perpendicular to the X direction is referred to as the "Z direction" (third direction perpendicular to both the first and second directions), and the direction perpendicular to the X and Z directions is referred to as the "Y direction" (second direction perpendicular to the first direction). The side from which the active energy irradiation device 1 emits ultraviolet rays is referred to as the "lower side" (one side in the Z direction), and the opposite side is referred to as the "upper side." One side in the Y direction is referred to as the "front side," and the other side in the Y direction is referred to as the "rear side."

[0025] The housing 2 has a rectangular shape that is elongated in the Z direction. The housing 2 is made of metal. The housing 2 houses and supports the active energy irradiation unit 3, the heat sink 4, and the duct 7. The housing 2 is configured by assembling a front case 21 and a rear case 22. A gripping portion 23 for grasping the housing 2 is provided on the upper wall 2a of the housing 2. A driver board 12, whose thickness direction is the Y direction, is arranged on the rear side inside the housing 2. The driver board 12 is an electric circuit board for driving the active energy irradiation device 1. A driver board heat sink 13 for cooling transistors and the like on the driver board 12 is arranged on the driver board 12. The driver board heat sink 13 is thermally connected to the transistors and the like on the driver board 12.

[0026] The active energy irradiation unit 3 includes a rectangular plate-shaped substrate 31 that forms a predetermined circuit, and LED elements 32 that are light-emitting elements and are arranged side by side on the substrate 31 at a predetermined pitch in the X and Y directions. The LED elements 32 emit ultraviolet light downward. The active energy irradiation unit 3 is disposed at the lower end inside the housing 2, with the thickness direction of the substrate 31 aligned in the Z direction. The multiple substrates 31 are aligned in the X direction. As a result, several to several hundred LED elements 32 are aligned in the X and Y directions inside the housing 2. The ultraviolet light emitted from each LED element 32 of the active energy irradiation unit 3 is irradiated onto an irradiation target moving in the Y direction through a light irradiation window 24 made of a glass plate provided in the bottom wall 2b of the housing 2. The multiple substrates 31 may be aligned in the X and Y directions.

[0027] The heat sink 4 is a heat dissipation member thermally connected to the LED elements 32 of the active energy irradiation unit 3. The heat sink 4 is an air-cooled heat sink that dissipates heat by heat exchange with air. The air serves as a heat medium (refrigerant) for cooling the LED elements 32. The heat sink 4 has a base plate 41, heat dissipation fins 42, heat pipes 43, and a partition plate (partition member) 44.

[0028] The base plate 41 has a rectangular plate shape. The active energy irradiation unit 3 is provided on the lower surface of the base plate 41. The lower surface of the base plate 41 abuts against the substrate 31 of the active energy irradiation unit 3. The heat dissipation fins 42 have a flat plate shape with the Y direction as the thickness direction. The heat dissipation fins 42 are provided upright on the upper surface (surface) of the base plate 41. The heat dissipation fins 42 are arranged so as to be stacked with gaps in the Y direction.

[0029] The heat pipes 43 are embedded in the plurality of heat dissipation fins 42. The heat pipes 43 are thermally connected to the plurality of heat dissipation fins 42. The partition plates 44 are arranged so as to intersect with the plurality of heat dissipation fins 42. The partition plates 44 are flat and have a thickness direction in the X direction. The partition plates 44 separate the plurality of heat dissipation fins 42 in the X direction. A pair of partition plates 44 are provided on the plurality of heat dissipation fins 42, spaced apart from each other in the X direction. The pair of partition plates 44 divide the plurality of heat dissipation fins 42 into a pair of outer portions 42x located on the outsides in the X direction and an inner portion 42y located between the pair of outer portions.

[0030] The end of the partition plate 44 on the base plate 41 side is separated from the base plate 41. In other words, the partition plate 44 separates the plurality of heat dissipation fins 42 so that air passes through the lower side (the base plate 41 side) between the plurality of heat dissipation fins 42 in the X direction more easily than the upper side (the side opposite the base plate 41 side). The partition plate 44 is fixed to the plurality of heat dissipation fins 42 by brazing. The heat sink 4 is attached to the housing 2 via a bracket 25 and a support frame 26 (see FIG. 7).

[0031] The intake unit 5 introduces air from the outside of the housing 2 into the inside of the housing 2. The intake unit 5 introduces air into a buffer space BF (described later) inside the housing 2. The intake unit 5 is provided in a central upper portion of the front wall 2c of the housing 2. The intake unit 5 has an intake filter (filter unit) 51, a filter holder 52, and an intake port 53.

[0032] As shown in Figures 4, 5, 6, and 7, the intake filter 51 captures foreign matter (dust, etc.) contained in the air introduced into the housing 2. The intake filter 51 is made of, for example, urethane. The intake filter 51 has a rectangular plate-like outer shape. When viewed from the front, the intake filter 51 extends to an upper central portion of the wall portion 2c. The filter holder 52 houses and holds the intake filter 51. The filter holder 52 has a rectangular outer plate 52x whose thickness direction is in the Y direction. The front surface of the outer plate 52x is located on the same plane as the front surface of the wall portion 2c of the housing 2. The filter holder 52 is detachably attached to the duct 7 and a support frame 27 provided on the duct 7.

[0033] The air intake ports 53 are through-holes that open along the Y direction (a direction intersecting the direction from the heat sink 4 toward the exhaust section 6) and lead to the inside of the housing 2. The air intake ports 53 are arranged side by side and close to each other in regions at both ends of the outer plate 52x in the X direction. The air intake ports 53 are elongated through-holes with the Z direction as their longitudinal direction. Air sucked in through the air intake ports 53 is introduced into the buffer space BF inside the housing 2 via the air intake filter 51 (see FIG. 8).

[0034] The exhaust unit 6 exhausts air from inside the housing 2 to outside the housing 2. The exhaust unit 6 is provided at the upper end of the housing 2. The exhaust unit 6 has a fan 61. For example, an axial fan is used as the fan 61. The fan 61 pressurizes and sends air sucked in from below in the Z direction to above in the Z direction. The fan 61 is fixed to the upper end inside the housing 2. An exhaust filter 62 made of, for example, urethane is attached to the discharge side of the fan 61, on the top wall 2a of the housing 2. For convenience, the exhaust filter 62 is shown only in FIG. 2 and is not shown in other figures. The discharge side of the fan 61 in the exhaust unit 6 is connected to an external pipe (not shown) for exhausting air to, for example, the outdoors.

[0035] The duct 7 is provided inside the housing 2 between the heat sink 4 and the exhaust section 6. The duct 7 circulates air that has passed through the heat sink 4 to the exhaust section 6. The duct 7 circulates inert gas that has passed through the heat sink 4 to the exhaust section 6. The duct 7 has a rectangular pipe shape. The duct 7 has a straight section 71 that extends in the Z direction with a constant cross-sectional area, and an expanding section 72 that is provided downstream of the straight section 71 and extends in the Z direction so that the cross-sectional area increases downstream.

[0036] A buffer space BF (see FIG. 8 ), into which air is introduced from the outside by the intake section 5, is provided on one side and the other side of the duct 7 in the X direction inside the housing 2. The buffer space BF is a space defined by the inner surface of the housing 2 and the outer surfaces of the straight section 71 and the expanded section 72 of the duct 7. The lower end of the duct 7 is inserted into and fixed to a groove 47 formed in the heat dissipation fin 42 of the heat sink 4. The upper end of the duct 7 is fixed to the suction side of the fan 61. The duct 7 is attached to the housing 2 via a support frame 27.

[0037] As shown in FIGS. 2, 3, 4, and 5, the inert gas supply unit 8 supplies an inert gas to the outside of the housing 2. Examples of the inert gas include nitrogen. By supplying the inert gas, the inert gas supply unit 8 forms a region dominated by the inert gas (a region with a low oxygen concentration) in an area including an area irradiated with ultraviolet light from the LED elements 32. The inert gas supply unit 8 is attached to the lower end of the front wall 2c of the housing 2. The inert gas supply unit 8 has a rectangular box-shaped purge housing 81, a socket 82 provided on the upper end surface of the purge housing 81, and an outlet 83 provided on the lower end of the purge housing 81. In the inert gas supply unit 8, the inert gas is introduced from the socket 82 into the purge housing 81 and then ejected from the outlet 83.

[0038] The inert gas suction unit 9 sucks in the inert gas outside the housing 2 and causes it to flow into the inside of the housing 2. The inert gas suction unit 9 is a structure attached to the housing 2. The inert gas suction unit 9 is detachably attached to the rear side of the bottom wall 2b of the housing 2 with fasteners such as screws. The inert gas suction unit 9 has a rectangular box-shaped suction unit housing 91, a suction port 92 provided on the bottom surface of the suction unit housing 91, and a recovery flow path 93 provided inside the suction unit housing 91 (see FIG. 7). The inert gas suction unit 9 sucks in the inert gas into the inside of the suction unit housing 91 through the suction port 92, and the inert gas is circulated into the inside of the housing 2 via the recovery flow path 93.

[0039] As shown in FIGS. 6, 7, and 8, in the active energy irradiation device 1, external air is introduced into the buffer space BF inside the housing 2 by the intake unit 5. The air introduced into the buffer space BF flows downward along the Z direction, passes through the heat sink 4, and flows into the duct 7. At this time, in the heat sink 4, the air flows downward along the Z direction between the plurality of heat dissipation fins 42 of each of the pair of outer portions 42x, then flows upward between the partition plate 44 and the base plate 41, and merges at the inner portion 42y. The air then flows upward along the Z direction between the plurality of heat dissipation fins 42 of the inner portion 42y and flows into the duct 7.

[0040] Furthermore, the air introduced into the buffer space BF flows downward in the Z direction, and then passes through the driver board heat sink 13. The air that has passed through the driver board heat sink 13 passes through a lower rear space inside the housing 2, joins the flow in the inner portion 42y of the heat sink 4, flows upward in the Z direction between the multiple heat dissipation fins 42 of the inner portion 42y, and flows into the duct 7. The air that has flowed into the inside of the duct 7 flows upward in the Z direction and is discharged to the outside of the housing 2 via the fan 61.

[0041] 7, in the active energy irradiation device 1, the inert gas ejected from the inert gas supply unit 8 is sucked by the inert gas suction unit 9 and flows into the interior of the housing 2. The inert gas that has flowed into the interior of the housing 2 passes through a lower rear space inside the housing 2, joins the flow in the inner portion 42y of the heat sink 4, flows upward along the Z direction between the multiple heat dissipation fins 42 of the inner portion 42y together with the air, and flows into the duct 7. The inert gas that has flowed into the interior of the duct 7 flows upward along the Z direction together with the air, and is discharged to the outside of the housing 2 together with the air via the fan 61.

[0042] The configuration of the inert gas supply unit 8 will be described in more detail with reference to FIGS.

[0043] 9 and 10, the inert gas supply unit 8 supplies the inert gas to a region R between the irradiated object S and the active energy irradiation unit 3 by spraying the inert gas (indicated by the dashed-dotted line in FIGS. 9 and 10) onto the irradiated object S being transported from the front side to the rear side by a conveyor (not shown). The inert gas is supplied to the region R in order to prevent the action occurring in the irradiated object S due to the irradiation of ultraviolet rays emitted from the active energy irradiation unit 3 from being inhibited by oxygen in the air.

[0044] As an example, the irradiated object S is a printed material to which photocurable ink is attached. The ink is sprayed onto the irradiated object S from an ink head (not shown) on the upstream side (front side) of the active energy irradiation device 1, and is cured by irradiation with ultraviolet light emitted from the active energy irradiation unit 3. At this time, in order to prevent the curing of the ink from being inhibited by oxygen in the air, the inert gas supply unit 8 supplies an inert gas to a region R between the irradiated object S and the active energy irradiation unit 3.

[0045] As shown in FIG. 9, the inert gas supply unit 8 has a rectifying plate 84 in a purge housing 81. A socket 82 is provided on a purge top surface 81a of the purge housing 81. A rectifying plate 84 is fixed to a purge front surface 81b of the purge housing 81. The rectifying plate 84 includes a first vertical surface 85, an inclined surface 86, and a second vertical surface 87. A purge bottom surface 81c of the purge housing 81 forms a part of the outlet 83. A purge back surface 81d of the purge housing 81 contacts the front surface of the wall portion 2c of the housing 2. The rectifying plate 84 cooperates with the purge housing 81 to form a flow path through which the inert gas passes.

[0046] The inert gas supply unit 8 includes a first flow path portion 8 a and a second flow path portion 8 b. The inert gas received from the socket 82 passes through the first flow path portion 8 a, then the second flow path portion 8 b, and is finally ejected from the ejection port 83.

[0047] The first flow path section 8a receives the inert gas from the socket 82 and supplies the inert gas to the second flow path section 8b. The first flow path section 8a is an area surrounded by the purge upper surface 81a, the first vertical surface 85, the inclined surface 86, and the purge rear surface 81d. The first flow path section 8a includes a portion where the flow path area decreases along the direction in which the inert gas flows. Specifically, the first flow path section 8a includes a portion between the first vertical surface 85 and the purge rear surface 81d and a portion between the inclined surface 86 and the purge rear surface 81d. The distance between the first vertical surface 85 and the purge rear surface 81d is constant. Therefore, the flow path area is constant. Meanwhile, the inclined surface 86 is inclined with respect to the Z direction. In other words, the lower side 86a of the inclined surface 86 is located further rearward in the Y direction than the upper side 86b of the inclined surface 86. As a result, the flow path area gradually decreases as the first flow path section 8a approaches the second flow path section 8b.

[0048] The socket 82 is provided on the purge upper surface 81a so that the axis L of the socket 82 is located approximately in the center between the purge front surface 81b and the purge back surface 81d. In other words, the axis L of the socket 82 intersects with the inclined surface 86. In other words, the axis L of the socket 82 is located between the lower side 86a and the upper side 86b of the inclined surface 86 in the Y direction. As a result, the flow of inert gas received from the socket 82 collides with the inclined surface 86. Then, the inert gas flows along the inclined surface 86 toward the rear side in the Y direction and reaches the second flow path portion 8b.

[0049] The second flow path section 8b receives the inert gas from the first flow path section 8a and supplies the inert gas to the outlet 83. In other words, the second flow path section 8b guides the inert gas toward the irradiated object S along the Z direction. The second flow path section 8b is a region surrounded by the second vertical surface 87 and the purge rear surface 81d. The region between the upper side of the second vertical surface 87 (i.e., the lower side 86a of the inclined surface 86) and the purge rear surface 81d receives the compressed inert gas. The distance between the second vertical surface 87 and the purge rear surface 81d is constant. In other words, the flow path area of ​​the second flow path section 8b is constant. The flow path area of ​​the second flow path section 8b is smaller than the flow path area of ​​the portion of the first flow path section 8a between the first vertical surface 85 and the purge rear surface 81d. The flow path area of ​​the second flow path section 8b is the same as the flow path area of ​​the portion of the first flow path section 8a between the lower side 86a of the inclined surface 86 and the purge rear surface 81d.

[0050] The end of the second flow path section 8b corresponds to the ejection port 83. The ejection port 83 is formed between the lower end 87a of the second vertical surface 87 and the lower end 81e of the purge back surface 81d. The rear end 81f of the purge bottom surface 81c may be part of what constitutes the ejection port 83. The inert gas ejected onto the irradiated object S from the ejection port 83 changes its flow direction after colliding with the irradiated object S. Some of the inert gas flows toward the rear side and is supplied to the region R (see FIG. 10) between the irradiated object S and the active energy irradiation unit 3. Another part of the inert gas flows toward the front side and prevents air from flowing into the region R (see FIG. 10) between the irradiated object S and the active energy irradiation unit 3.

[0051] In the inert gas supply unit 8 configured as described above, the flow area of ​​the first flow path section 8a is larger than the flow area of ​​each of the socket 82 and the second flow path section 8b. The rectifying plate 84, which is disposed in the first flow path section 8a so as to intersect with the axis L of the socket 82, obstructs the flow of the inert gas received from the socket 82. This causes the flow of the inert gas received from the socket 82 to spread in the X direction, resulting in a uniform flow rate distribution of the inert gas ejected from the ejection port 83 in the X direction. Therefore, the inert gas can be efficiently supplied to the region R (see FIG. 10 ) between the irradiated object S and the active energy irradiation unit 3. Furthermore, the rectifying plate 84 has a slope 86 that obstructs the flow of the inert gas. In other words, the rectifying plate 84 realizes a flow path configuration in which the flow area gradually decreases. This reduces the operating noise of the inert gas supply unit 8.

[0052] The housing 2, the active energy irradiation unit 3, the inert gas supply unit 8, and the inert gas suction unit 9 will be described in more detail with reference to FIGS.

[0053] As shown in Figures 3 and 10, the active energy irradiation unit 3 has an exit surface 30 that emits ultraviolet light downward. In the active energy irradiation device 1, the exit surface 30 is the lower surface (outer surface) of the light irradiation window 24. The exit surface 30 extends in both the X and Y directions. In the active energy irradiation device 1, the exit surface 30 is a surface perpendicular to the Z direction and has a rectangular shape with the X direction as the longitudinal direction. As an example, the width 30x of the exit surface 30 in the X direction is about 100 mm, and the width 30y of the exit surface 30 in the Y direction is about 25 mm.

[0054] The inert gas supply unit 8 has an outlet 83 on its lower side that ejects inert gas. In the active energy irradiation device 1, the outlet 83 has a slit shape extending in the X direction. The outlet 83 is located in front of the emission surface 30. The inert gas supply unit 8 includes an ejection portion 80 in which the outlet 83 is provided. The ejection portion 80 is a portion of the inert gas supply unit 8 that protrudes downward from the emission surface 30 (the portion below the two-dot chain line shown in Figures 3 and 10). In the active energy irradiation device 1, the outer shape of the ejection portion 80 is a rectangular plate with the X direction as the longitudinal direction and the Z direction as the thickness direction. The inert gas supply unit 8 is attached to the housing 2 (specifically, the front wall portion 2c) so that the ejection portion 80 is located below the emission surface 30 in the Z direction.

[0055] Note that "the nozzle 83 ejects the inert gas downward" means that the ejection direction of the inert gas from the nozzle 83 has a downward component. In other words, the nozzle 83 may eject the inert gas directly downward, or may eject the inert gas from directly below in a direction tilted rearward, for example.

[0056] The inert gas suction unit 9 includes a protruding portion 90 that protrudes downward from the emission surface 30. The protruding portion 90 is located rearward from the emission surface 30. In the active energy irradiation device 1, the entire inert gas suction unit 9 is the protruding portion 90. The inert gas suction unit 9 is attached to the housing 2 (specifically, the bottom wall 2b) so that the protruding portion 90 (i.e., the entire inert gas suction unit 9) is located below the emission surface 30 in the Z direction. The inert gas suction unit 9 includes a suction unit housing (box body) 91 provided with a plurality of suction ports 92. In the active energy irradiation device 1, the outer shape of the suction unit housing 91 is a rectangular plate with the X direction as the longitudinal direction and the Z direction as the thickness direction.

[0057] In the active energy irradiation device 1, the lower surface (outer surface) of the lower wall 2b is exposed between the emission surface 30 and the ejection portion 80 and between the emission surface 30 and the protruding portion 90. The distance between the emission surface 30 and the ejection portion 90 in the Y direction is smaller than the distance between the emission surface 30 and the ejection portion 80 in the Y direction. For example, the distance between the emission surface 30 and the ejection portion 80 in the Y direction is approximately 40 mm, and the distance between the emission surface 30 and the ejection portion 90 in the Y direction is approximately 20 mm. The lower surface of the lower wall 2b and the surface of the protruding portion 90 are surfaces that absorb ultraviolet light. For example, the lower surface of the lower wall 2b and the surface of the protruding portion 90 may be a black painted surface, a black treated surface, or a surface of a black material.

[0058] The width 90y of the protruding portion 90 in the Y direction is larger than the width 90z of the protruding portion 90 in the Z direction. The width 90y of the protruding portion 90 in the Y direction is at least nine times the width 90z of the protruding portion 90 in the Z direction. The width 90y is preferably at least eight times the width 90z, and more preferably at least ten times the width 90z. The width 80z of the ejected portion 80 in the Z direction is larger than the width 90z of the protruding portion 90 in the Z direction. As an example, the width 90x of the protruding portion 90 in the X direction is approximately 100 mm, the width 90y of the protruding portion 90 in the Y direction is approximately 45 mm, and the width 90z of the protruding portion 90 in the Z direction is approximately 5 mm. As an example, the width 80x of the ejected portion 80 in the X direction is approximately 100 mm, the width 80y of the ejected portion 80 in the Y direction is approximately 25 mm, and the width 80z of the ejected portion 80 in the Z direction is approximately 5 mm.

[0059] The width of the active energy irradiation unit 3 in the X direction, the width of the inert gas supply unit 8 in the X direction, and the width of the inert gas suction unit 9 in the X direction are each equal to or less than the width of the housing 2 in the X direction. The width 83x of the jet outlet 83 in the X direction and the width 90x of the protruding portion 90 in the X direction are each equal to the width 30x of the emission surface 30 in the X direction. Here, "equal" means "substantially equal," meaning, for example, that the width 83x and the width 90x are each 95% or more of the width 30x and 105% or less of the width 30x. Note that the width 83x of the jet outlet 83 in the X direction and the width 90x of the protruding portion 90 in the X direction may each be smaller than the width 30x of the emission surface 30 in the X direction. The width 83x and the width 90x are each preferably 90% or more of the width 30x, more preferably 100% or more, and even more preferably 110% or more.

[0060] As described above, in the active energy irradiation device 1, when the irradiated object S is transported from the front side to the rear side relative to the exit surface 30 of the active energy irradiation unit 3, the inert gas ejected from the ejection port 83 of the inert gas supply unit 8 is supplied to the region R between the irradiated object S and the active energy irradiation unit 3. At this time, the protruding portion 90, whose width 90y in the Y direction is greater than its width 90z in the Z direction, is located rearward relative to the exit surface 30 of the active energy irradiation unit 3, making it difficult for the inert gas to flow out from the region R between the irradiated object S and the active energy irradiation unit 3 to the downstream side (rear side) in the transport direction of the irradiated object S. Therefore, the active energy irradiation device 1 can prevent oxygen from being mixed into the region R between the irradiated object S and the active energy irradiation unit 3. The active energy irradiation device 1 can create a high-concentration and uniform nitrogen gas atmosphere in the region R between the irradiated object S and the active energy irradiation unit 3 without significantly increasing the amount of inert gas supplied to the inert gas supply unit 8, even when the transport speed of the irradiated object S increases.

[0061] In the active energy irradiation device 1, the inert gas supply unit 8 includes a jetting portion 80 provided with a jetting port 83 and protruding downward relative to the emission surface 30. This makes it difficult for air to flow from the upstream side (front side) in the conveying direction of the irradiated object S into the region R between the irradiated object S and the active energy irradiation unit 3. Therefore, it is possible to more reliably suppress the intrusion of oxygen into the region R between the irradiated object S and the active energy irradiation unit 3.

[0062] In the active energy irradiation device 1, the width 80z of the ejection portion 80 in the Z direction is larger than the width 90z of the protruding portion 90 in the Z direction. As a result, the ejection port 83 of the inert gas supply unit 8 is closer to the irradiated object S, making it difficult for air to flow from the upstream side in the conveying direction of the irradiated object S into the region R between the irradiated object S and the active energy irradiation unit 3. Therefore, it is possible to more reliably suppress oxygen from being mixed into the region R between the irradiated object S and the active energy irradiation unit 3.

[0063] In the active energy irradiation device 1, the width in the X direction of the active energy irradiation section 3, the width in the X direction of the inert gas supply section 8, and the width in the X direction of the inert gas suction section 9 are each equal to or less than the width in the X direction of the housing 2. This allows a plurality of active energy irradiation devices 1 to be arranged so that the housings 2 come into contact with each other in the X direction, making it possible to deal with an irradiated object S that is wide in the X direction.

[0064] In the active energy irradiation device 1, the width 83x of the outlet 83 in the X direction and the width 90x of the protruding portion 90 in the X direction are each equal to the width of the emission surface 30 in the X direction. As a result, in a plurality of active energy irradiation devices 1 arranged so that the housings 2 are in contact with each other in the X direction, it is possible to uniformly irradiate ultraviolet rays onto the irradiation object S which is wide in the X direction while suppressing oxygen from being mixed into the region R between the irradiation object S and the plurality of active energy irradiation units 3.

[0065] In the active energy irradiation device 1, the inert gas suction part 9 is detachably attached to the housing 2. This allows the replacement and maintenance of the inert gas suction part 9 to be easily performed.

[0066] In the active energy irradiation device 1, the protruding portion 90 has a surface that absorbs ultraviolet light. This makes it possible to prevent ultraviolet light from being reflected by the protruding portion 90 and irradiating unwanted areas with ultraviolet light. For example, it is possible to prevent ultraviolet light reflected by the protruding portion 90 from being irradiated onto an ink head (not shown) arranged upstream of the active energy irradiation device 1, thereby making it possible to prevent photocurable ink from being cured in the ink head.

[0067] In the active energy irradiation device 1, the inert gas suction unit 9 includes a box-shaped suction unit housing 91. This makes it possible to prevent the inert gas from flowing out from the region R between the irradiated object S and the active energy irradiation unit 3 to the downstream side in the conveying direction of the irradiated object S.

[0068] In the active energy irradiation device 1, the inert gas suction unit 9 has a suction port 92 for sucking in the inert gas. This allows the inert gas supplied to the region R between the irradiated object S and the active energy irradiation unit 3 to be efficiently collected.

[0069] In the active energy irradiation device 1, the active energy irradiation section 3 emits ultraviolet light as active energy rays. This allows the active energy irradiation device 1 to be used as a device that irradiates the irradiation target S with ultraviolet light.

[0070] In the active energy irradiation device 1, the distance between the exit surface 30 and the protruding portion 90 in the Y direction is smaller than the distance between the exit surface 30 and the jetting portion 80 in the Y direction. This makes it possible to prevent the concentration of the inert gas from decreasing in the region R between the irradiated object S and the active energy irradiation unit 3.

[0071] The results of experiments conducted to confirm the effects and advantages will be described with reference to FIGS.

[0072] As an example of the active energy irradiation device 1, as shown in FIG. 11(a), an active energy irradiation device 1 having a protruding portion 90 with a width of 45 mm in the Y direction (horizontal direction in the figure) and a width of 5 mm in the Z direction (vertical direction in the figure) was prepared. In the active energy irradiation device 1 of the example, the distance between the nozzle 83 and the protruding portion 90 was set to 85 mm. In the active energy irradiation device 1 of the example, nitrogen gas was supplied to the inert gas supply unit 8 at 27 L / min, while the irradiated object S was transported from left to right in the figure at 150 m / min. As a result, the region R between the irradiated object S and the active energy irradiation unit 3 became a highly concentrated and uniform nitrogen gas atmosphere, as shown in FIG. 11(a).

[0073] As the active energy irradiation device 1 of Comparative Example 1, an active energy irradiation device 1 not having a configuration corresponding to the protruding portion 90 was prepared, as shown in (b) of FIG. 11. The other configurations were the same as those of the active energy irradiation device 1 of the Example. In the active energy irradiation device 1 of Comparative Example 1, nitrogen gas was supplied to the inert gas supply unit 8 at 27 L / min, while the irradiated object S was transported from left to right in the figure at 150 m / min. As a result, the region R between the irradiated object S and the active energy irradiation unit 3 did not become a sufficient nitrogen gas atmosphere, as shown in (b) of FIG. 11.

[0074] As the active energy irradiation device 1 of Comparative Example 2, an active energy irradiation device 1 having a configuration corresponding to a protruding portion 90 having a width of 1 mm in the Y direction and a width of 5 mm in the Z direction, as shown in FIG. 12(a), was prepared. In the active energy irradiation device 1 of Comparative Example 2, the distance between the nozzle 83 and the configuration corresponding to the protruding portion 90 was 85 mm. The other configurations were the same as those of the active energy irradiation device 1 of the Example. In the active energy irradiation device 1 of Comparative Example 2, nitrogen gas was supplied to the inert gas supply unit 8 at 27 L / min, and the irradiated object S was transported from left to right in the figure at 150 m / min. As a result, the region R between the irradiated object S and the active energy irradiation unit 3 did not become a sufficient nitrogen gas atmosphere, as shown in FIG. 12(a).

[0075] As the active energy irradiation device 1 of Comparative Example 3, an active energy irradiation device 1 having a configuration corresponding to a protruding portion 90 having a width of 1 mm in the Y direction and a width of 5 mm in the Z direction, as shown in (b) of FIG. 12, was prepared. In the active energy irradiation device 1 of Comparative Example 3, the distance between the nozzle 83 and the configuration corresponding to the protruding portion 90 was 139 mm. The other configurations were the same as those of the active energy irradiation device 1 of the Example. In the active energy irradiation device 1 of Comparative Example 3, nitrogen gas was supplied to the inert gas supply unit 8 at 27 L / min, and the irradiated object S was transported from left to right in the figure at 150 m / min. As a result, the region R between the irradiated object S and the active energy irradiation unit 3 did not become a sufficient nitrogen gas atmosphere, as shown in (3) of FIG. 12.

[0076] From the above experimental results, it was found that when a protruding portion 90 whose width in the Y direction is larger than its width in the Z direction is located behind (to the right in the figure) the exit surface 30 of the active energy irradiation unit 3 (active energy irradiation device 1 of the embodiment), it becomes difficult for nitrogen gas to flow out from the region R between the irradiated object S and the active energy irradiation unit 3 to the downstream side in the conveying direction of the irradiated object S (to the right in the figure). It was found that even if a configuration corresponding to the protruding portion 90 whose width in the Y direction is smaller than its width in the Z direction is located behind (to the active energy irradiation device 1 of Comparative Example 2 and the active energy irradiation device 1 of Comparative Example 3) the same effect as that obtained when a configuration corresponding to the protruding portion 90 is not located (active energy irradiation device 1 of Comparative Example 1) was not obtained.

[0077] The present invention is not limited to the above-described embodiment. For example, the structure including the protruding portion 90 is not limited to the inert gas suction unit 9. As an example, a structure 9A shown in FIG. 13(a), a structure 9B shown in FIG. 13(b), or a structure 9C shown in FIG. 13(c) may be applied to the active energy irradiation device 1 instead of the inert gas suction unit 9. As shown in FIG. 13(a), the structure 9A includes a box body 94 or a block body 95. The box body 94 or the block body 95 has an outer shape of a rectangular plate with the X direction as the longitudinal direction and the Z direction as the thickness direction. As shown in FIG. 13(b), the structure 9B includes a plurality of plate bodies 96 arranged in the Y direction. Each plate body 96 has, for example, a rectangular plate shape with the X direction as the longitudinal direction and the Y direction as the thickness direction. As shown in FIG. 13(c), the structure 9C includes a plurality of plate bodies 97 arranged in the X direction. Each plate 97 has, for example, a rectangular plate shape with the Y direction as the longitudinal direction and the X direction as the thickness direction.

[0078] In a structure including the protruding portion 90 (for example, the inert gas suction unit 9, structures 9A, 9B, and 9C), the protruding portion 90 protruding downward from the emission surface 30 may be a part of the structure. In that case, it is sufficient that at least the protruding portion 90 has a surface that absorbs ultraviolet light.

[0079] The structure including the protruding portion 90 (for example, the inert gas suction unit 9, structures 9A, 9B, and 9C) is not limited to being detachably attached to the housing 2 by fasteners such as screws, and the detachable attachment structure may be any other known attachment structure. For example, the structure may have a guided portion that is slidable relative to a guide portion of the housing 2, thereby allowing the structure to be detachably attached to the housing 2.

[0080] The inert gas supply unit 8 does not have to include a portion that protrudes downward from the emission surface 30. The ejection port 83 may be provided in a portion of the inert gas supply unit 8 that is located above the emission surface 30.

[0081] The support that supports the active energy irradiation unit 3, the inert gas supply unit 8, and the structures (e.g., the inert gas suction unit 9, the structures 9A, 9B, and 9C) is not limited to the housing 2, but may have other support structures such as a frame.

[0082] 14, the active energy irradiation device 1 may include a pair of shielding plates 10 arranged on one side and the other side in the X direction with respect to the exit surface 30 of the active energy irradiation unit 3. This makes it difficult for the inert gas to flow out to one side and the other side in the X direction from the region R between the irradiated object S and the active energy irradiation unit 3, even when the active energy irradiation device 1 is used alone. Therefore, it is possible to more reliably suppress the intrusion of oxygen into the region R between the irradiated object S and the active energy irradiation unit 3.

[0083] The active energy irradiation unit 3 is not limited to emitting ultraviolet rays, and may emit other active energy rays such as electron beams. In other words, in the above description, "ultraviolet rays" can be read as "electron beams" or "active energy rays."

[0084] The respective configurations in the above-described embodiments and modifications are not limited to the materials and shapes described above, and various materials and shapes can be applied. The respective configurations in the above-described embodiments or modifications can be arbitrarily applied to the respective configurations in other embodiments or modifications. [Explanation of symbols]

[0085] 1...active energy irradiation device, 2...housing (support), 3...active energy irradiation section, 30...exit surface, 8...inert gas supply section, 10...shielding plate, 80...ejection section, 83...ejection port, 9...inert gas suction section (structure), 9A, 9B, 9C...structure, 90...protruding section, 91...suction section housing (box body), 92...suction port

Claims

1. an active energy irradiation unit having an exit surface extending in both a first direction and a second direction perpendicular to the first direction, the exit surface emitting active energy rays to one side in a third direction perpendicular to both the first direction and the second direction; an inert gas supply unit having an ejection port located on one side of the emission surface in the second direction, the ejection port ejecting an inert gas to the one side in the third direction; a structure including a protruding portion located on the other side of the light exit surface in the second direction, the protruding portion protruding on the one side of the light exit surface in the third direction; a support supporting the active energy irradiation unit, the inert gas supply unit, and the structure, the support has an exposed surface between the emission surface and the ejection port and between the emission surface and the protruding portion, the protruding portion has a surface located on the one side in the third direction with respect to the surface of the support body, the emission surface, the surface of the support, and the surface of the protruding portion are each a surface perpendicular to the third direction, The width of the protruding portion in the second direction is greater than the width of the protruding portion in the third direction.

2. The active energy irradiation device according to claim 1 , wherein the inert gas supply unit includes a jetting portion provided with the jetting port and protruding from the emission surface to the one side in the third direction.

3. The active energy irradiation device according to claim 2 , wherein a width of the ejected portion in the third direction is larger than a width of the protruding portion in the third direction.

4. An active energy irradiation device described in any one of claims 1 to 3, wherein the width of the active energy irradiation section in the first direction, the width of the inert gas supply section in the first direction, and the width of the structure in the first direction are each less than or equal to the width of the support in the first direction.

5. The active energy irradiation device according to claim 4 , wherein the width of the ejection port in the first direction and the width of the protruding portion in the first direction are each equal to the width of the emission surface in the first direction.

6. The active energy irradiation device according to claim 4 or 5, wherein the structure is detachably attached to the support.

7. 7. The active energy irradiation device according to claim 1, wherein at least the protruding portion has a surface that absorbs the active energy rays.

8. The active energy irradiation device according to any one of claims 1 to 7, wherein the structure includes a box or a block.

9. The active energy irradiation device according to any one of claims 1 to 7, wherein the structure includes a plurality of plates.

10. 10. The active energy irradiation device according to claim 1, wherein the structure has a suction port for sucking the inert gas.

11. The active energy irradiation device according to any one of claims 1 to 10, further comprising a pair of shielding plates arranged on one side and the other side of the emission surface in the first direction.

12. The active energy irradiation device according to any one of claims 1 to 11, wherein the active energy irradiation unit emits ultraviolet rays or electron beams as the active energy rays.

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