JP7793066B2 - light irradiation device - Google Patents

Description

This invention relates to a light irradiation device that emits light, and in particular to a light irradiation device equipped with a heat dissipation member that dissipates heat emitted from a light source.

Printing devices that print using UV ink that hardens when exposed to ultraviolet light are known. In such printing devices, ink is ejected from the nozzles of the head onto a medium, and then ultraviolet light is applied to the dots formed on the medium. The ultraviolet light exposure hardens the dots, allowing for good printing even on media that do not easily absorb liquid.

For example, Patent Document 1 describes a printing device that includes a transport unit that transports the print medium, six heads aligned in the transport direction and ejecting cyan, magenta, yellow, black, orange, and green color inks, six pre-curing irradiation units (light irradiation devices) positioned downstream between the heads in the transport direction to pre-cure (pin) the ink dots ejected onto the print medium from each head, and a final curing irradiation unit that final cures the ink dots and fixes them to the print medium. Furthermore, in order to make the printing device lightweight and compact, the pre-curing irradiation units use LEDs as light sources, with multiple LEDs aligned across the width of the print medium.

JP 2013-252720 A

When using an LED as a light source, as in the light irradiation device described in Patent Document 1, most of the input electricity is converted into heat, which creates problems such as reduced light-emitting efficiency and lifespan due to the heat generated by the LED itself.

This problem becomes even more serious in a device equipped with multiple LEDs, such as the light irradiation device of Patent Document 1, because the number of LEDs that serve as heat sources increases. Furthermore, when UV LEDs are used as the light source, as in the light irradiation device of Patent Document 1, the amount of heat generated by the LEDs themselves increases, making this problem even more serious.
For this reason, light irradiation devices that use LEDs as light sources generally employ a configuration in which a heat dissipation member such as a heat sink is used to suppress heat generation from the LEDs.

However, when using such a heat dissipation component such as a heat sink, an intake and exhaust system is required to cool the heat dissipation component. When multiple peripheral devices are placed close to the light irradiation device, as in the printing device of Patent Document 1, problems arise such as insufficient intake and exhaust, and the heat dissipation component cannot be sufficiently cooled.
It is also possible to lay out the printer so that sufficient space is provided between the peripheral device and the light irradiation device to allow for sufficient intake and exhaust, but this would result in the printer itself becoming larger.

The present invention was made in consideration of the above circumstances, and its purpose is to provide a light irradiation device that can efficiently cool an LED (light source) and that can be placed in close proximity to peripheral devices.

To achieve the above-mentioned objective, the light irradiation device of the present invention is a light irradiation device that irradiates an irradiation object with light that has a predetermined line width in a first direction and extends in a second direction perpendicular to the first direction, and includes a light source unit having a substrate defined by the first direction and a second direction perpendicular to the first direction, a plurality of light sources arranged in a line on the surface of the substrate along the second direction and that emit light in a third direction perpendicular to the first and second directions, a heat dissipation unit having a plurality of heat dissipation fins and thermally coupled to the back side of the substrate, and a first absorption unit that takes in air from the outside. The lamp comprises a first housing having a first air intake port and a first exhaust port for exhausting the air inside, and accommodating a light source unit and a heat dissipation unit; and a first cooling fan attached to at least one of the first air intake port and the first exhaust port for generating cooling air that passes between a plurality of heat dissipation fins, wherein the first air intake port is formed on one end face of the first housing in the second direction, and the first exhaust port is formed on the other end face of the first housing in the second direction, and the first air intake port and the first exhaust port are located outside the object to be irradiated in the second direction.

With this configuration, the first air intake and first exhaust ports are formed on the end face of the first housing in the second direction and are located outside the object to be irradiated, so air intake and exhaust occur only along the second direction. This makes it possible to arrange peripheral devices and multiple light irradiation devices of the same type or the same kind closely together along the first direction. Furthermore, when the object to be irradiated is transported in the first direction, the light source can be sufficiently cooled without the exhaust air or waste heat from the light irradiation device affecting the object to be irradiated.

Furthermore, the device is provided with a partition plate that divides the space within the first housing, forming a first wind tunnel in the space connected to the first air intake port, a second wind tunnel in the space where multiple heat dissipation fins are arranged, and a third wind tunnel in the space connected to the first exhaust port, and it is desirable that the partition plate has a communication port formed to connect the first wind tunnel and the second wind tunnel, and that the second wind tunnel and the third wind tunnel are connected via the heat dissipation fins.

Furthermore, it is desirable that the communication opening consists of multiple openings arranged along the second direction, and that each opening has the same width in the first direction.

Furthermore, it is desirable that the communication opening consists of multiple openings lined up along the second direction, and that the width of each opening in the first direction varies depending on the distance from the first cooling fan. In this case, the width of each opening in the first direction can be configured to decrease with increasing distance from the first cooling fan. Also, the width of each opening in the first direction can be configured to increase with increasing distance from the first cooling fan.

It is also desirable that the first cooling fan takes in air from the outside and generates cooling air in the second direction within the first wind tunnel and the third wind tunnel.

It is also desirable that the cooling air be redirected from the first direction to the third direction, or from the third direction to the first direction, within the second wind tunnel.

The device also includes a shading unit arranged opposite the light source unit and blocking light irradiated from the light source unit to prevent it from leaking to the outside. The shading unit has a light-absorbing member that absorbs light irradiated from the light source unit, a second air intake port that takes in air from the outside, a second air exhaust port that exhausts internal air, and a second housing that supports the light-absorbing member. A fourth wind tunnel is formed inside the second housing, through which cooling air flows from the second air intake port toward the second exhaust port. It is desirable that, in the second direction, the two air intake ports and the second exhaust port are located outside the object to be irradiated.

Furthermore, it is desirable that the second air intake port be formed on one end surface of the second housing in the second direction, the second exhaust port be formed on the other end surface of the second housing in the second direction, and that a second cooling fan be attached to at least one of the second air intake port and the second exhaust port and generate cooling air that flows through the fourth wind tunnel.

It is also desirable that the first air intake port and the second air intake port are formed on the same side in the second direction.

It is also desirable that the first exhaust port and the second exhaust port are formed on the same side in the second direction.

It is also desirable that the object to be irradiated is transported in the first direction.

As described above, the present invention provides a light irradiation device that can efficiently cool the light source and that can be placed in close proximity to peripheral devices.

1 is an external view showing a configuration of a light irradiation device according to an embodiment of the present invention. 1 is an external view of a light source unit included in a light irradiation device according to an embodiment of the present invention. 2A and 2B are diagrams illustrating an internal configuration of a light source unit included in the light irradiation device according to the embodiment of the present invention. 2A and 2B are diagrams illustrating an internal configuration of a light source unit included in the light irradiation device according to the embodiment of the present invention. 2A and 2B are diagrams illustrating an internal configuration of a light source unit included in the light irradiation device according to the embodiment of the present invention. 2A and 2B are diagrams illustrating an internal configuration of a light source unit included in the light irradiation device according to the embodiment of the present invention. 2A and 2B are diagrams illustrating an internal configuration of a light source unit included in the light irradiation device according to the embodiment of the present invention. 2A and 2B are diagrams illustrating an internal configuration of a light source unit included in the light irradiation device according to the embodiment of the present invention. 3A and 3B are diagrams illustrating the configuration of a light blocking unit included in the light irradiation device according to the embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Note that identical or corresponding parts in the drawings will be given the same reference numerals and their descriptions will not be repeated.

FIG. 1 is an external view showing the configuration of a light irradiation device 1 according to an embodiment of the present invention. As shown in FIG. 1, the light irradiation device 1 is an apparatus for curing an ultraviolet-curable resin applied to the surface of an irradiation object P (e.g., a recording medium, etc.) being transported. The light irradiation device 1 is composed of a light source unit 10 disposed above the irradiation object P and emitting a line of ultraviolet light toward the irradiation object P, and a light-shielding unit 20 disposed opposite the light source unit 10 so as to cover the irradiation object P from below. Note that in this specification, the longitudinal direction of the line of ultraviolet light emitted from the light source unit 10 is defined as the X-axis direction (second direction), the line width direction of the line of ultraviolet light is defined as the Y-axis direction (first direction), and the direction perpendicular to the X-axis and Y-axis is defined as the Z-axis direction (third direction).

(Configuration of light source unit 10)
FIG. 2 is an external view of the light source unit 10 of this embodiment, with FIG. 2(a) being a front view of the light source unit 10, FIG. 2(b) being a right side view of the light source unit 10, and FIG. 2(c) being a left side view of the light source unit 10. FIGS. 3 to 8 are diagrams illustrating the internal configuration of the light source unit 10 according to an embodiment of the present invention, with FIG. 3 being a cross-sectional view taken along line B-B in FIG. 2, FIG. 4 being a cross-sectional view taken along line C-C in FIG. 2, FIG. 5 being a cross-sectional view taken along line D-D in FIG. 2, FIG. 6 being a cross-sectional view taken along line E-E in FIG. 2, FIG. 7 being a cross-sectional view taken along line F-F in FIG. 2, and FIG. 8 being a cross-sectional view taken along line G-G in FIG. 2. Note that in FIGS. 3 to 8, some components, such as wiring cables inside the light source unit 10, are omitted for clarity.

As shown in FIG. 4 , the light source unit 10 of this embodiment includes a box-shaped housing 100 elongated in the X-axis direction, which houses an LED module 200 (light source), a cooling fan 300 (first cooling fan), a heat sink 400 (heat dissipation unit), an LED drive circuit 500, and the like. The housing 100 includes a glass window 105 on the front surface 100a through which ultraviolet light is emitted. An exhaust port 101 consisting of multiple openings S is formed on the left side surface 100c of the housing 100 for exhausting air from within the housing 100, and an intake port 103 is formed on the right side surface 100b for supplying air into the housing 100. A connector (not shown) for supplying power to the light source unit 10 is provided on the back surface 100d of the housing 100. The connector is electrically connected to a power supply (not shown) so that power is supplied to the light source unit 10.

As shown in Figures 3 to 8, the light source unit 10 of this embodiment includes, within the housing 100, four LED modules 200 (Figure 4) arranged in a line in the X-axis direction, four heat sinks 400 (Figure 4) arranged in close contact with each LED module 200, and four LED drive circuits 500 (Figures 3, 4, and 7) that supply power to each LED module 200. Note that each LED module 200, each heat sink 400, and each LED drive circuit 500 has the exact same configuration.

As shown in Figures 3 and 4, each LED module 200 comprises a rectangular plate-shaped substrate 205 defined in the X-axis and Y-axis directions and formed from a material with high thermal conductivity (e.g., aluminum nitride), and multiple (e.g., 500) LED elements 210 having the same characteristics, and is fixed on one end surface (the end surface in the Z-axis direction) of the heat sink 400's heat dissipation plate 410.

The multiple LED elements 210 are arranged, for example, in an array of 50 elements (in the X-axis direction) x 10 rows (in the Y-axis direction) and mounted using COB (chip-on-board) technology. An anode pattern (not shown) and a cathode pattern (not shown) are formed on the substrate 205 to supply power to each LED element 210, and each LED element 210 is electrically connected to the anode pattern and cathode pattern, respectively. Furthermore, the substrate 205 of each LED module 200 is electrically connected to each LED drive circuit 500 via a wiring cable (not shown), and each LED element 210 is supplied with drive current from each LED drive circuit 500 via the anode pattern and cathode pattern. When a drive current is supplied to each LED element 210, each LED element 210 emits ultraviolet light (e.g., wavelength 365 nm) with an amount of light corresponding to the drive current, and the LED module 200 emits linear ultraviolet light that extends in the X-axis direction and has a predetermined line width in the Y-axis direction orthogonal to the X-axis direction toward the irradiation object P. As shown in Fig. 4, in this embodiment, four LED modules 200 are arranged side by side in the X-axis direction, and the linear ultraviolet light emitted from each LED module 200 is continuous in the X-axis direction.

The heat sink 400 is a component that dissipates heat generated by the LED module 200. In this embodiment, the heat sink 400 is composed of a rectangular metal (e.g., copper or aluminum) heat dissipation plate 410 and multiple heat dissipation fins 420 brazed to the other end surface of the heat dissipation plate 410 (the surface opposite to the surface on which the LED module 200 is mounted) (Figures 3 and 4). The heat dissipation fins 420 are rectangular metal (e.g., copper, aluminum, iron, magnesium, or an alloy containing any of these) components that protrude from the heat dissipation plate 410 in the direction opposite to the Z-axis direction and dissipate heat transferred to the heat dissipation plate 410 into the air.

3, the LED module 200 and heat sink 400 of this embodiment are fixed within the housing 100 by a fixing member 150. The fixing member 150 is a member that supports a portion of the LED module 200 and heat sink 400, and when the LED module 200 and heat sink 400 are fixed within the fixing member 150, each LED element 210 is positioned opposite the window portion 105. Furthermore, when the LED module 200 and heat sink 400 are fixed within the fixing member 150, the end of the heat dissipation fin 420 in the direction opposite to the Z-axis direction is configured to abut against the first partition plate 161 of the partition member 160.

When a drive current flows through each LED element 210 and ultraviolet light is emitted from each LED element 210, the temperature rises due to self-heating of the LED element 210. However, the heat generated by each LED element 210 is quickly conducted (moved) to the heat dissipation fins 420 via the substrate 205 and heat sink 410, and is then dissipated from each heat dissipation fin 420 into the surrounding air. The air heated by the heat dissipation fins 420 is then quickly exhausted through the exhaust port 101 by the cooling air flowing over the surface of each heat dissipation fin 420.

The cooling fan 300 is positioned opposite the air intake 103 and is a component that draws in air from outside the housing 100 and generates cooling air inside the housing 100 (Figures 4 to 8). In this embodiment, the cooling fan 300 is positioned at one end (the end in the X-axis direction) of the partition member 160 that divides the space within the housing 100 (Figure 5).

3 , the partition member 160 is a member having a substantially U-shaped cross section formed by bending a metal plate, and includes a first partition plate 161 against which an end of the heat dissipation fin 420 facing in the direction opposite to the Z-axis direction abuts, a second partition plate 162 facing the upper surface (the surface facing in the Y-axis direction) of the housing 100, and a third partition plate 163 facing the lower surface (the surface facing in the direction opposite to the Y-axis direction) of the housing 100. The first partition plate 161, the second partition plate 162, and the third partition plate 163 each extend from the cooling fan 300 toward the left side surface 100 c of the housing 100 in the direction opposite to the X-axis direction, and form a first air channel α that guides air taken in by the cooling fan 300 in the direction opposite to the X-axis direction in a space surrounded by the back surface 100 d of the housing 100 (i.e., a space continuous with the air intake port 103). The other ends (ends opposite to the X-axis direction) of the first partition plate 161, the second partition plate 162, and the third partition plate 163 abut against the left side surface 100c of the housing 100, and the first air tunnel α is closed by the left side surface 100c of the housing 100 in the direction opposite to the X-axis direction (Figure 4).
As shown in FIGS. 3, 4 and 7, in this embodiment, four LED drive circuits 500 are arranged in the first wind tunnel α.

The first partition plate 161 is a partition plate parallel to the XY plane, and has four rectangular communication openings 161a-161d aligned in the X-axis direction so as to face the heat dissipation fins 420 (FIGS. 7 and 8). Each of the communication openings 161a-161d is an opening for directing the cooling air in the first air channel α to the space (second air channel β) of the heat dissipation fins 420. The widths Wa-Wd of each of the communication openings 161a-161d in the X-axis direction are approximately equal to the width of the heat sink 400 of each LED module 200, and the widths Ha-Hd of each of the communication openings 161a-161d in the Y-axis direction are formed to satisfy the relationship Ha>Hb>Hc>Hd (i.e., the widths vary depending on the distance from the cooling fan 300, becoming smaller the farther away from the cooling fan 300) (FIG. 8).
As shown in Figures 7 and 8, the first partition plate 161 in this embodiment abuts approximately the center of the heat dissipation fin 420, and the upper end (the end in the Y-axis direction) and lower end (the end in the direction opposite to the Y-axis direction) of the heat dissipation fin 420 are exposed from the first partition plate 161 (i.e., located in the third wind tunnels γ1 and γ2).

In the configuration of this embodiment, the four LED modules 200 and heat sinks 400 are arranged side by side in the X-axis direction, which creates the problem of variations in the amount of light emitted if the temperatures of the LED elements 210 in each LED module 200 differ. To solve this problem, this embodiment is configured so that air flows between each heat dissipation fin 420 through the communication openings 161a to 161d, thereby making the amount of air flowing through each heat sink 400 approximately equal (i.e., making the wind speed approximately equal), and uniformly cooling the four heat sinks 400.

In this embodiment, the widths Ha to Hd of each communication opening 161a to 161d in the Y-axis direction are formed to satisfy the relationship Ha > Hb > Hc > Hd (i.e., they change depending on the distance from the cooling fan 300, becoming smaller the farther away from the cooling fan 300), but the widths Ha to Hd of each communication opening 161a to 161d in the Y-axis direction may be equal as long as the four heat sinks 400 can be cooled uniformly.

The second partition plate 162 is a partition plate parallel to the XZ plane and is arranged to face the top surface (the surface in the Y-axis direction) of the housing 100, forming a third wind tunnel γ1 in the space within the housing 100 (Figures 3, 5, 7, and 8). As shown in Figure 5, in this embodiment, the third wind tunnel γ1 is a space continuous with the exhaust port 101, where the upper end (the end in the Y-axis direction) of the heat dissipation fin 420 is located, and which communicates with the second wind tunnel β via the heat dissipation fin 420.

The third partition plate 163 is a partition plate parallel to the XZ plane and is arranged to face the underside of the housing 100 (the surface opposite the Y-axis direction), forming a third wind tunnel γ2 in the space within the housing 100 (Figures 3, 6, 7, and 8). As shown in Figure 6, the third wind tunnel γ2, like the third wind tunnel γ1, is a space continuous with the exhaust port 101, and the lower end of the heat dissipation fin 420 (the end opposite the Y-axis direction) is located there, communicating with the second wind tunnel β via the heat dissipation fin 420.

The cooling action of the heat sink 400, which is a characteristic feature of the present invention, will be explained below using Figures 3 to 6. The arrows in Figures 3 to 6 indicate the direction of the cooling air generated within the heat sink 400 and the housing 100.

As shown in Figures 3 to 6, the light source unit 10 of this embodiment is equipped with a cooling fan 300 located opposite the air intake 103 on the right side surface 100b of the housing 100, and an exhaust port 101 is formed on the left side surface 100c of the housing 100. Therefore, when the cooling fan 300 rotates, air outside the housing 100 is drawn in by the cooling fan 300, creating positive pressure inside the housing 100, and air inside the housing 100 is exhausted through the exhaust port 101. Therefore, cooling air is generated inside the housing 100, as indicated by the solid arrows in Figure 4. In other words, the air drawn into the housing 100 by the cooling fan 300 flows through the first air channel α within the housing 100, in which the LED drive circuits 500 are arranged, between each LED drive circuit 500, in a direction opposite to the X-axis direction. Therefore, heat generated by each LED drive circuit 500 is dissipated into the air moving through the first air channel α. In this manner, in this embodiment, the LED drive circuits 500 are arranged in the first air tunnel α, thereby cooling the LED drive circuits 500 .

As described above, the first wind tunnel α is closed by the left side surface 100c of the housing 100 in the direction opposite to the X-axis direction, so the air in the first wind tunnel α passes through the four communication ports 161a to 161d formed in the first partition plate 161 and moves toward the space of the heat dissipation fin 420 (the second wind tunnel β) (Figures 3 and 4).

The air that moves into the second wind tunnel β passes between each heat dissipation fin 420 and travels in the Z-axis direction, but when it hits the heat dissipation plate 410, it is bent between each heat dissipation fin 420 in the Y-axis direction and in the direction opposite to the Y-axis direction (Figure 3).Then, the air that leaves the space between the heat dissipation fins 420 (second wind tunnel β) moves to the third wind tunnels γ1 and γ2, and travels within the third wind tunnels γ1 and γ2 in the direction opposite to the X-axis direction before being discharged from the exhaust port 101 (Figures 5 and 6).

In this manner, in this embodiment, air taken in by the cooling fan 300 flows through the first air tunnel α, moves to the second air tunnel β, moves to the third air tunnels γ1 and γ2, and is discharged through the exhaust port 101. This movement of air generates cooling air (airflow). In this manner, as the cooling air passes through the space between the heat dissipation fins 420 (second air tunnel β), heat from each heat dissipation fin 420 is dissipated into the air.

As mentioned above, in this embodiment, the widths Ha to Hd in the Y-axis direction of the communication openings 161a to 161d of the first partition plate 161 satisfy the relationship Ha > Hb > Hc > Hd, and the amount of air flowing through each heat sink 400 is approximately equal (i.e., the air speed is approximately equal), so the four heat sinks 400 are cooled uniformly. As a result, the temperature of the LED elements 210 in each LED module 200 is approximately equal, and variations in light intensity are also reduced.

In addition, the air intake 103 and exhaust 101 are located on one end surface and the other end surface of the housing 100, and are positioned outside the object to be irradiated P, and the air intake and exhaust directions are limited to only directions opposite to the X-axis direction, so the air intake and exhaust do not affect the object to be irradiated P.
Furthermore, since the air intake and exhaust directions are limited to only the direction opposite to the X-axis direction, even if a peripheral device is placed close to the Y-axis direction of the housing 100 or in the direction opposite to the Y-axis direction, it will not affect the peripheral device, and the peripheral device will not interfere with the intake and exhaust of air.

As mentioned above, in this embodiment, the heat from the LED module 200 conducted to the heat sink 400 is cooled by air supplied through the space within the housing 100, so the housing 100 itself does not become hot.

(Configuration of light blocking unit 20)
Fig. 9 is a diagram illustrating the configuration of the light-shielding unit 20 of this embodiment, and is a cross-sectional view taken along line A-A in Fig. 1. As shown in Fig. 1 and Fig. 9, the light-shielding unit 20 is disposed opposite the light source unit 10 so as to cover the irradiation object P from below (the Z-axis direction side), and is a device that blocks ultraviolet light emitted from the light source unit 10 so as not to leak to the outside.

1 and 9, the light-shielding unit 20 has a case 21 (second housing) with a recess 21a formed therein that is recessed in the Z-axis direction so as to cover the irradiation object P from below. The case 21 is a box-shaped metal member, and the surface of the recess 21a facing the irradiation object P (i.e., the surface facing the window portion 105 of the light source unit 10) is made of a light-absorbing material 22. Ultraviolet light that does not hit the irradiation object P is absorbed by the light-absorbing material 22 and does not leak outside the light irradiation device 1.

However, when ultraviolet light from the light source unit 10 is irradiated onto the light-shielding unit 20, heat from the light-absorbing member 22 in the recess 21a is transferred to the case 21, raising the temperature of the light-shielding unit 20 itself. To address this issue, this embodiment forms a space (fourth wind tunnel δ) within the case 21, allowing cooling air to flow through the fourth wind tunnel δ (Figure 9). More specifically, the right side plate 21b of the case 21 is formed with an intake port 21ba (second intake port) that draws air into the fourth wind tunnel δ from the outside, and the left side plate 21c of the case 21 is formed with an exhaust port 21ca (second exhaust port) that exhausts air from the fourth wind tunnel δ. An exhaust fan 30 (second cooling fan) is positioned opposite the exhaust port 21ca, allowing cooling air to flow through the space (fourth wind tunnel δ) that is continuous with the intake port 21ba and the exhaust port 21ca.

9, when exhaust fan 30 rotates, air inside case 21 is exhausted from exhaust fan 30, creating a negative pressure inside case 21, and external air is drawn into case 21 through intake port 21ba. Therefore, cooling air is generated inside case 21 from intake port 21ba toward exhaust port 21ca, as indicated by the solid arrows in Fig. 9. In other words, the air drawn into case 21 from intake port 21ba flows along the rear surface of recess 21a through fourth air tunnel δ in a direction opposite to the X-axis direction, thereby cooling recess 21a.
In this manner, in this embodiment, the heat in the recess 21a of the case 21 is cooled by the cooling air (air) flowing through the space within the case 21 (fourth wind tunnel δ), so the case 21 itself does not become hot.

In addition, the air intake 21ba and the air exhaust 21ca are located on one end face and the other end face of the case 21, and are positioned outside the object to be irradiated P, and the air intake and exhaust directions are limited to only directions opposite to the X-axis direction, so the air intake and exhaust do not affect the object to be irradiated P.
Furthermore, since the air intake and exhaust directions are limited to only the direction opposite to the X-axis direction, even if a peripheral device is placed close to the Y-axis direction of the housing 100 or in the direction opposite to the Y-axis direction, it will not affect the peripheral device, and the peripheral device will not interfere with the intake and exhaust of air.

The above is a description of this embodiment, but the present invention is not limited to the above configuration and various modifications are possible within the scope of the technical concept of the present invention.

For example, the light irradiation device 1 of this embodiment has been described as comprising a light source unit 10 and a shading unit 20, but it is not necessarily limited to this configuration, and the shading unit 20 can be provided as needed.

In addition, although the light irradiation device 1 of this embodiment is described as a device that hardens ultraviolet-curable resin applied to the surface of an irradiation object P (e.g., a recording medium, etc.) being transported, it is sufficient that the device emits line-shaped ultraviolet light toward the irradiation object P, and the irradiation object P does not necessarily have to be transported.

In addition, although the light source unit 10 in this embodiment is a device that irradiates ultraviolet light, it is not limited to this configuration, and the present invention can also be applied to devices that irradiate light in other wavelength ranges (e.g., visible light such as white light, infrared light, etc.).

In addition, in the light source unit 10 of this embodiment, the cooling fan 300 has been described as an intake fan, but it can also be an exhaust fan. In this case, the air flow is reversed, with air being drawn in through the exhaust port 101 and exhausted through the intake port 103 (i.e., the air intake and exhaust directions are in the X-axis direction). In this case, the widths Ha to Hd in the Y-axis direction of each communication port 161a to 161d of the first partition plate 161 may be formed to satisfy the relationship Ha<Hb<Hc<Hd (i.e., they change depending on the distance from the cooling fan 300, becoming larger the further away from the cooling fan 300).

In addition, although the shading unit 20 of this embodiment uses an exhaust fan 30, the exhaust fan 30 can also be replaced with an intake fan. In this case, the air flow will be reversed, and the air inside the case 21 will be exhausted from the intake port 21ba (i.e., the air intake and exhaust directions will be in the X-axis direction).

In addition, in this embodiment, the air intake 103 of the light source unit 10 and the air intake 21ba of the shading unit 20 are formed on the same side (end face in the X-axis direction), but this configuration is not necessarily limited to this, and they may be formed on different sides in the X-axis direction.
Furthermore, although the exhaust port 101 and the exhaust fan 30 are formed on the same side (the end face in the direction opposite to the X-axis direction), this configuration is not necessarily limited to this, and they may be formed on different sides in the X-axis direction.

The embodiments disclosed herein are illustrative in all respects and should not be considered limiting. The scope of the present invention is indicated by the claims, not the above description, and is intended to include all modifications within the meaning and scope of the claims.

1: Light irradiation device 10: Light source unit 20: Light blocking unit 21: Case 21a: Recess 21b: Right side plate 21ba: Air intake port 21c: Left side plate 21ca: Exhaust port 22: Light absorbing member 30: Exhaust fan 100: Housing 100a: Front surface 100b: Right side surface 100c: Left side surface 100d: Rear surface 101: Exhaust port 103: Air intake port 105: Window portion 150: Fixing member 160: Partition member 161: First partition plate 161a: Communication port 161b: Communication port 161c: Communication port 161d: Communication port 162: Second partition plate 163: Third partition plate 200: LED module 205: Board 210: LED element 300: Cooling fan 400 : Heat sink 410 : Heat sink 420 : Heat sink fin 500 : LED drive circuit P : Irradiation target S : Opening α : First wind tunnel β : Second wind tunnel γ1 : Third wind tunnel γ2 : Third wind tunnel δ : Fourth wind tunnel

Claims (8)

A light irradiation device that irradiates an irradiation object with light having a predetermined line width in a first direction and extending in a second direction perpendicular to the first direction,
a light source unit including a substrate defined by the first direction and the second direction, and a plurality of light sources arranged on a surface of the substrate along the second direction and emitting light in a third direction orthogonal to the first direction and the second direction;
a heat dissipation unit having a plurality of heat dissipation fins and thermally coupled to the rear surface side of the substrate;
a first housing having a first air intake port for taking in air from the outside and a first air exhaust port for exhausting air from the inside, and accommodating the light source unit and the heat dissipation unit;
a partition plate that divides a space within the first housing, forming a first wind tunnel in a space continuous with the first air intake port, a second wind tunnel in a space in which the plurality of heat dissipation fins are disposed, and a third wind tunnel in a space continuous with the first air exhaust port;
a first cooling fan attached to at least one of the first air intake port and the first air exhaust port, the first cooling fan generating cooling air that passes between the plurality of heat dissipation fins;
Equipped with
the first air intake port is formed on one end surface of the first housing in the second direction,
the first exhaust port is formed on the other end surface of the first housing in the second direction,
In the second direction, the first intake port and the first exhaust port are located outside the irradiation object ,
the partition plate has a communication port formed to communicate the first wind tunnel with the second wind tunnel,
the second wind tunnel and the third wind tunnel communicate with each other via a heat dissipation fin;
The communication port is made up of a plurality of openings aligned along the second direction,
a width of each of the openings in the first direction decreasing with increasing distance from the first cooling fan ; 2. The light irradiation device according to claim 1 , wherein the first cooling fan takes in air from the outside and generates cooling air in the second direction in the first wind tunnel and the third wind tunnel. 2. The light irradiation device according to claim 1 , wherein the cooling air changes direction in the second air channel from the first direction to the third direction or from the third direction to the first direction. a light-shielding unit disposed opposite the light source unit and configured to block light emitted from the light source unit so that the light does not leak to the outside;
The light-shielding unit is
a light absorbing member that absorbs light irradiated from the light source unit;
a second housing having a second intake port for taking in air from the outside and a second exhaust port for exhausting air from the inside, and supporting the light absorbing member;
and
a fourth air channel is formed inside the second housing, through which cooling air flows from the second air intake port toward the second air exhaust port;
4. The light irradiation device according to claim 1 , wherein the second intake port and the second exhaust port are located outside the irradiation object in the second direction. the second intake port is formed on one end surface of the second housing in the second direction,
the second exhaust port is formed on the other end surface of the second housing in the second direction,
5. The light irradiation device according to claim 4 , further comprising a second cooling fan attached to at least one of the second air intake port and the second exhaust port, the second cooling fan generating cooling air flowing through the fourth wind tunnel. 6. The light irradiation device according to claim 5 , wherein the first air intake port and the second air intake port are formed on the same side in the second direction. 7. The light irradiation device according to claim 6 , wherein the first exhaust port and the second exhaust port are formed on the same side in the second direction. The light irradiation device according to claim 4 , wherein the irradiation object is transported in the first direction.