KR102469921B1 - Light illuminating apparatus - Google Patents

Abstract

(assignment)
To provide a light irradiation device that reliably prevents leakage of ultraviolet rays to the outside and also prevents heat generation of a housing.
(solution)
A light irradiation device for irradiating light onto an irradiation target transported along a first direction includes a light source unit having a plurality of LED elements and irradiating light on the irradiation target from a second direction orthogonal to the first direction; a light absorbing member disposed to face the light source unit while sandwiching the transport path of the light source unit and blocking light emitted from the light source unit so that light emitted from the light source unit does not leak to the outside; It has a housing for accommodating and supporting at least a part of the light absorbing member, and a wind tunnel formed between the housing and the light absorbing member and through which cooling air flows.

Description

Light irradiation device {LIGHT ILLUMINATING APPARATUS}

[0001] The present invention relates to a light irradiation device for irradiating light to a conveyed irradiation target.

BACKGROUND OF THE INVENTION [0002] Conventionally, there is known a printing apparatus that performs printing using UV ink that is cured by irradiation with ultraviolet light. In such a printing apparatus, after ejecting ink from a nozzle of a head onto a medium, dots formed on the medium are irradiated with ultraviolet light. Since the dots are hardened and fixed to the medium by irradiation with ultraviolet light, good printing can be performed even on a medium that does not easily absorb liquid.

In an ultraviolet light irradiation device used in such a printing device, a light emitting diode (LED) element is used as a light source instead of a conventional discharge lamp due to recent requests for reduction in power consumption, long life, and compact size of the device. It is provided for practical use (for example, Patent Document 1).

The light irradiation device described in Patent Literature 1 has a work arrangement space in a housing, irradiates ultraviolet rays from a plurality of LED elements to a work passing through the work arrangement space, and cures an ultraviolet curing resin on the work.

Japanese Unexamined Patent Publication No. 2018-118499

According to the structure of Patent Literature 1, since ultraviolet light is irradiated to the work passing through the work arrangement space (ie, the space within the housing), leakage of ultraviolet light to the outside of the work arrangement space is temporarily prevented. However, when ultraviolet rays are irradiated in a closed space called a work arrangement space, ultraviolet rays are reflected in various places such as the housing part and the work itself in the work arrangement space, so it is difficult to completely prevent the leakage of ultraviolet rays to the outside of the work arrangement space. . In addition, when ultraviolet rays hit the housing part in the work arrangement space, the housing heats up and there is also a problem that contact with the housing becomes impossible.

The present invention has been made in view of such a situation, and its object is to provide a light irradiation device that reliably prevents leakage of ultraviolet rays to the outside of the light irradiation device and also prevents heat generation of the housing.

In order to achieve the above object, a light irradiation device of the present invention is a light irradiation device for irradiating light to an object to be irradiated that is transported along a first direction, has a plurality of LED elements, and has a second direction orthogonal to the first direction. A light source unit for radiating light to an object to be irradiated from the light source unit, and a light blocking unit disposed to face the light source unit and interposing a conveyance path of the object to be irradiated, and blocking light so that the light emitted from the light source unit does not leak to the outside, the light blocking unit comprising: It is characterized by having a light absorbing member that absorbs light irradiated from the light source unit, a housing accommodating and supporting at least a portion of the light absorbing member, and a wind tunnel formed between the housing and the light absorbing member through which cooling air flows.

According to this configuration, since the light blocking unit absorbs the light emitted from the light source unit by the light absorbing member, leakage of ultraviolet rays to the outside of the light irradiation device is prevented. Further, since cooling air flows between the housing and the light absorbing member, heat generation of the light blocking unit is also prevented.

Further, it is preferable that the housing has a box-shaped shape having an opening on the transport path side, and a first intake port for introducing air into the wind tunnel from the outside is formed in at least a part of this opening. In this case, the housing preferably has a second intake port for introducing air into the wind tunnel from the outside at one end of the first direction and the third direction orthogonal to the second direction.

In addition, the housing may be configured to have an exhaust fan for exhausting air in the wind tunnel to the outside at the other end of the third direction orthogonal to the first and second directions.

Further, it is preferable that the light absorbing member has a box-like shape with an opening on the transport path side and is attached to the housing with a predetermined gap therebetween. In this case, the light absorbing member preferably has black electroless nickel plating or chrome plating on the inner surface.

Further, it is preferable that one end of the light source unit and the light blocking unit is connected via a hinge.

Further, it is preferable that the light emitted from the light source unit is ultraviolet light.

As described above, according to the present invention, a light irradiation device that reliably prevents leakage of ultraviolet rays to the outside of the light irradiation device and also prevents heat generation of the housing is realized.

1 is a diagram showing the configuration of a light irradiation device according to an embodiment of the present invention.
Figure 2 is a BB line cross-sectional view of Figure 1 (b).
Figure 3 is a cross-sectional view taken along line AA of Figure 1 (a).
4 is a cross-sectional view taken along line CC of FIG. 1(b).
5 is an exploded perspective view of a light blocking unit included in a light irradiation device according to an embodiment of the present invention.
6 is a diagram showing a modified example of the light irradiation device according to the embodiment of the present invention.

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described in detail with reference to drawings. In addition, the same code|symbol is attached|subjected to the same or equivalent part in drawing, and the description is not repeated.

1 is a diagram showing the configuration of a light irradiation device 1 according to an embodiment of the present invention, FIG. 1(a) is a perspective view, and FIG. 1(b) is a front view. 2 is a cross-sectional view along line B-B of FIG. 1(b), and FIG. 3 is a cross-sectional view along line A-A of FIG. 1(a). As shown in Figs. 1 to 3, the light irradiation device 1 is a device for curing an ultraviolet curable resin applied to the surface of a conveyed irradiation target object P (eg, a recording medium), and the irradiation target object ( It is composed of a light source unit 10 disposed above P, and a light blocking unit 20 disposed opposite to the light source unit 10 across the transport path 40 of the object P to be irradiated. In the present specification, the X-axis direction is the longitudinal direction of ultraviolet light on a line emitted from the light source unit 10, the Y-axis direction is the transport direction of the object P to be irradiated, and the Z-axis is the direction orthogonal to the X-axis and Y-axis. Define and explain the direction.

As shown in FIGS. 2 and 3 , the light source unit 10 is a device for emitting line-shaped ultraviolet light along the X-axis direction, and includes a substrate 13 and a plurality of LED elements disposed on the substrate 13 ( 14), a cooling device 15, and a case 11 accommodating them.

The case 11 is a box-shaped housing made of metal having an opening on the bottom surface (the lower surface in FIGS. 1 to 3), and a glass window member 12 is fitted into the opening on the bottom surface (FIG. 2, 3). In addition, a pair of light blocking plates 17 are disposed on the bottom surface of the case 11 of the present embodiment so as to sandwich the window member 12 therebetween. Each light blocking plate 17 is a rectangular plate-shaped metal member defined in the X-axis direction and the Y-axis direction, and is attached so as to protrude from the case 11 in the Y-axis direction and in directions opposite to the Y-axis direction, respectively. The surface of each light blocking plate 17 facing the light blocking unit 20 (that is, the surface on the Z-axis direction side) is coated with black electroless nickel plating or chrome plating, so that ultraviolet light from the light source unit 10 Even if it touches the object P to be irradiated and is reflected, this reflected light is absorbed by each light blocking plate 17 so that it does not leak to the outside of the light irradiation device 1.

The substrate 13 is a rectangular wiring board defined in the X-axis direction and the Y-axis direction and made of a material with high thermal conductivity (eg, aluminum nitride). As shown in Figs. 2 and 3, on the surface of the substrate 13, a plurality of LED elements 14 are arranged in a row, for example, 150 (X-axis direction) x 4 columns (Y-axis direction), COB ( Chip On Board) is mounted. An anode pattern (not shown) and a cathode pattern (not shown) for supplying power to each LED element 14 are formed on the substrate 13, and each LED element 14 is connected to the anode pattern and the cathode pattern. They are electrically connected to each other. In addition, the substrate 13 is electrically connected to a driver circuit (not shown) by a wiring cable (not shown), and a driving current is supplied to each LED element 14 from the driver circuit through an anode pattern and a cathode pattern. have. When a driving current is supplied to each LED element 14, ultraviolet light (for example, a wavelength of 365 nm) according to the amount of light according to the driving current is emitted from each LED element 14, and the X-axis is emitted from the light source unit 10. Ultraviolet light on a line parallel to the direction is emitted. In addition, the drive current supplied to each LED element 14 is adjusted so that each LED element 14 of this embodiment emits ultraviolet light of a substantially uniform light quantity, and ultraviolet light on a line emitted from the light source unit 10 has a substantially uniform light quantity distribution in the X-axis direction.

The cooling device 15 is a so-called air-cooled heat sink that is disposed so as to be in close contact with the back surface of the substrate 13 and dissipates heat generated in each LED element 14 . The cooling device 15 includes a plurality of radiating fins 16 made of a material having good thermal conductivity such as aluminum or copper, a cooling fan (not shown), and the like, The radiating fins 16 are uniformly cooled.

When power is supplied to the light source unit 10 and ultraviolet light is emitted from each LED element 14, the self-heating of the LED element 14 causes a problem that the temperature rises and the luminous efficiency is remarkably lowered. , Since each LED element 14 is uniformly cooled by the cooling device 15 in this embodiment, occurrence of such a problem is suppressed.

4 and 5 are views explaining the configuration of the light shielding unit 20 of this embodiment, FIG. 4 is a cross-sectional view taken along the line C-C of FIG. 1(b), and FIG. 5 is an exploded perspective view. In addition, in FIG. 5, the light blocking plate 27 is omitted for convenience of description. As shown in FIGS. 2 and 3 , the light blocking unit 20 is disposed facing the light source unit 10 across the transport path 40 so that the ultraviolet light emitted from the light source unit 10 does not leak to the outside. It is a light blocking device. As shown in Fig. 3, the light blocking unit 20 and the light source unit 10 are connected by a hinge 50 provided at one end in the X-axis direction, and the other end of the light-shielding unit 20 in the X-axis direction is It is configured to be movable in a rotational direction centering on the portion. In this way, in the present embodiment, when the light blocking unit 20 moves in the rotational direction, the space between the light blocking unit 20 and the light source unit 10 is opened, so that the object P such as continuous paper is It becomes possible to install easily in the conveyance path 40.

As shown in FIGS. 2 to 5 , the light blocking unit 20 has a light absorbing member 22 and a case 21 (housing) for accommodating and supporting the light absorbing member 22 . The case 21 is a box-shaped metal member having an opening 21e on the conveyance path 40 side, and side plates 21a and 21b of the case 21 that face each other in the Y-axis direction have light absorbing members 22 A plurality of through holes 21g for fixing are formed, an inlet 21f for introducing air from the outside is formed in the side plate 21c in the X-axis direction of the case 21, and a side plate facing the side plate 21c. At 21d, an exhaust fan 30 for exhausting the air inside the case 21 to the outside is disposed. Further, as shown in Figs. 2 and 4, a pair of light blocking plates 27 are provided on side plates 21a and 21b of case 21 of the present embodiment. Each light shielding plate 27 is a metal bar-shaped member having an approximately L-shaped cross section in the YZ plane, and the upper side of the side plates 21a and 21b so that the flat portion 27a of the light shielding plate 27 faces the light shielding plate 17. (the side opposite to the Z-axis direction). The surface of the flat portion 27a of each light blocking plate 27 facing the light blocking plate 17 (that is, the surface on the side opposite to the Z-axis direction) is coated with black electroless nickel plating or chrome plating, etc. Even if ultraviolet light from the unit 10 is reflected inside the light shielding unit 20, the reflected light is absorbed by each light shielding plate 27 so as not to leak to the outside of the light irradiation device 1.

Further, the light absorbing member 22 is a box-shaped metal member having an opening 22e on the transport path 40 side, and a plurality of side plates 22a and 22b of the light absorbing member 22 facing each other in the Y-axis direction. A cylindrical boss material 23 is attached. Further, the upper side of the side plates 22c and 22d of the light absorbing member 22 that face each other in the X-axis direction (opposite to the Z-axis direction) protrude upward from the side plates 22a and 22b, and these protrusions are higher than the lower side. It has a wide width, and step portions 22f and 22g are formed, respectively. As shown in FIG. 5 , the light absorbing member 22 of this embodiment is inserted into the opening 21e of the case 21 and attached. When the light absorbing member 22 is inserted into the opening 21e of the case 21, the stepped portions 22f and 22g of the side plates 22c and 22d form the upper side (Z) of the side plates 21a and 21b of the case 21. Side opposite to the axial direction) Abuts against the end face and is positioned in the Z-axis direction. At this time, the position of each boss material 23 coincides with the position of each through hole 21g, and is fixed to the case 21 by a fixing screw (not shown) inserted into each through hole 21g. (FIG. 4, FIG. 5). When the light absorbing member 22 is fixed within the case 21, between the light absorbing member 22 and the case 21 (that is, between the side plate 21a and the side plate 22a, between the side plate 21b and the side plate 22b) ), between the bottom plate 21h and the bottom plate 22h), the space S is formed (Fig. 2).

The inner surface of the light absorbing member 22 of the present embodiment is coated with black electroless nickel plating or chrome plating for absorbing ultraviolet light from the light source unit 10, as indicated by the dotted line arrow in FIG. Similarly, ultraviolet light from the LED element 14 is made to enter between the side plates 22a and 22b. Therefore, even if the object P to be irradiated is cut midway, the ultraviolet light from the light source unit 10 is absorbed by the light absorbing member 22 and does not leak out of the light irradiation device 1 . 3, in this embodiment, in order to uniformly irradiate the object P, the irradiation width of the light source unit 10 in the X-axis direction is the X-axis of the object P Although configured to be longer than the width in the direction, ultraviolet light that does not reach the object P to be irradiated is also absorbed by the light absorbing member 22 and is prevented from leaking to the outside of the light irradiation device 1.

As described above, in the present embodiment, the light blocking unit 20 is disposed facing the light source unit 10 with the conveyance path 40 interposed therebetween, so that ultraviolet light emitted from the light source unit 10 does not leak to the outside. have. However, when the light blocking unit 20 is irradiated with ultraviolet light from the light source unit 10 in this way, there is a problem that the temperature of the light blocking unit 20 itself rises. Therefore, in the present embodiment, in order to solve this problem, a space S is formed between the light absorbing member 22 and the case 21, and cooling air flows through the space S. More specifically, an intake port 21f for introducing air into the space S from the outside is formed in the side plate 21c of the case 21, and the air in the space S is drawn into the side plate 21d of the case 21. An exhaust fan 30 for exhausting to the outside is arranged so that cooling wind flows through the space S. That is, the space S functions as a kind of wind tunnel.

That is, when the exhaust fan 30 rotates and the air in the space S is exhausted to the outside, negative pressure is generated in the space S, and the gap between the light absorbing member 22 and the case 21 (first intake port) Air is received into the space S through the , and is exhausted from the exhaust fan 30 by flowing in the space S in the X-axis direction (refer to the solid line arrow in FIG. 2 ). In addition, when the exhaust fan 30 rotates and the air in the space S is exhausted to the outside, air is also taken into the space S from the intake port 21f (second intake port) (see the solid line arrow in FIG. 3), It flows in the X-axis direction in the space (S) and is exhausted from the exhaust fan (30). In this way, in the light blocking unit 20 of the present embodiment, the light absorbing member 22 serving as a heat source is intensively cooled by forming a wind tunnel between the light absorbing member 22 and the case 21 . Further, by forming a wind tunnel between the light absorbing member 22 serving as a heat source and the case 21 (that is, by fixing the light absorbing member 22 to the case 21 via the boss material 23), the light absorbing member The heat resistance of the light absorbing member 22 is not transmitted to the case 21 by increasing the thermal resistance between the case 22 and the case 21 .

Although the above is the description of the present embodiment, the present invention is not limited to the above configuration, and various modifications are possible within the scope of the technical idea of the present invention.

For example, the light blocking unit 20 and the light source unit 10 of this embodiment are connected by a hinge 50 provided at one end in the X-axis direction, and the other end of the light-shielding unit 20 in the X-axis direction is Although it was set as being comprised so that it could move in the rotation direction centering on a part, it is not limited to such a structure. The light blocking unit 20 and the light source unit 10 may be configured integrally, or may be configured such that the light blocking unit 20 and the light source unit 10 are separated from each other along the Z-axis direction.

In addition, black electroless nickel plating or chrome plating for absorbing ultraviolet light from the light source unit 10 is applied to the inner surface of the light blocking unit 20 of the present embodiment, but for example, box-shaped light blocking A member that absorbs ultraviolet light may be attached to the inner surface of the unit 20 .

In addition, although the light absorbing member 22 of this embodiment is fixed to the case 21 via the boss material 23, it is not limited to such a fixing method. The light absorbing member 22 may be fixed so as to form a wind tunnel through which cooling air flows between the light absorbing member 22 and the case 21, and any other method may be applied.

(modified example)

6 is a diagram showing a modified example of the light irradiation device 1 according to the embodiment of the present invention. The light irradiation device 1A according to this modified example differs from the light irradiation device 1 of the present embodiment in that the shape of the light absorbing member 22A accommodated in the light blocking unit 20A is different.

More specifically, as shown in Fig. 6, in the light absorbing member 22A of this modified example, the upper ends of the side plates 22a and 22b are bent outward (ie, in the Y-axis direction and in the direction opposite to the Y-axis direction), respectively, to form a light blocking plate. A pair of planar portions 22z are formed to face (17). The surface of the flat portion 22z facing the light shielding plate 17 is coated with black electroless nickel plating or chrome plating, so that ultraviolet light from the light source unit 10 is reflected within the light shielding unit 20. Even on the sea, this reflected light is absorbed by the flat portion 22z and is configured so as not to leak to the outside of the light irradiation device 1A.

That is, in the light absorbing member 22A of the present modification, the configuration corresponding to the flat portion 27a (FIG. 2) of the light blocking plate 27 of the present embodiment (that is, the pair of flat portions 22z) is integrated. The light absorbing member 22A is accommodated and supported in the case 21 so that the pair of planar portions 22z face the light blocking plate 17. For this reason, according to this modified example, it is superior to the structure of this embodiment in that it is not necessary to separately install the light blocking plate 27, and the assembling process is simplified.

In addition, it should be thought that embodiment disclosed this time is an illustration in all respects, and is not restrictive. The scope of the present invention is indicated by the claims rather than the above description, and it is intended that all changes within the scope and meaning equivalent to the scope of the claims are included.

One… light irradiation device
1A... light irradiation device
10... light source unit
11... case
12... window absence
13... Board
14... LED element
15... cooling unit
16... heat sink fin
17... shading plate
20... shading unit
20A... shading unit
21... case
21a... shroud
21b... shroud
21c... shroud
21d... shroud
21e... opening
21 f... intake
21g... through hole
21h… bottom plate
22... light absorbing member
22A... light absorbing member
22a... shroud
22b... shroud
22c... shroud
22d... shroud
22e... opening
22f... stepped part
22g... stepped part
22h… bottom plate
22z... flat part
23... boss material
27... shading plate
27a... flat part
30... exhaust fan
40... return route
50... hinge
P… object of investigation
S... space

Claims (18)

A light irradiation device for irradiating light to an object to be irradiated that is conveyed along a first direction,
a light source unit having a plurality of LED elements and radiating light to the irradiation target from a second direction orthogonal to the first direction;
A light blocking unit disposed to face the light source unit and sandwiching the transport path of the object to be irradiated, and blocking the light irradiated from the light source unit so that the light is not leaked to the outside.
to provide,
The light blocking unit
a light absorbing member that absorbs the light emitted from the light source unit;
a housing accommodating and supporting at least a portion of the light absorbing member;
A wind tunnel formed between the housing and the light absorbing member and through which cooling wind flows
has,
The light irradiation device according to claim 1 , wherein the housing has a box-shaped shape having an opening on the transport path side, and a first intake port for introducing air into the wind tunnel from the outside is formed in at least a part of the opening. The light irradiation device according to claim 1, wherein the housing has a second intake port for introducing air into the wind tunnel from the outside at one end in a third direction orthogonal to the first and second directions. The light irradiation device according to claim 1, wherein the housing has an exhaust fan at the other end of the third direction orthogonal to the first direction and the second direction, for exhausting air in the wind tunnel to the outside. 3 . The light irradiation device according to claim 2 , wherein the housing has an exhaust fan at the other end of the third direction perpendicular to the first direction and the second direction, for exhausting air in the wind tunnel to the outside. The light irradiation device according to claim 1, which irradiates light to an object to be irradiated that is conveyed along a first direction,
a light source unit having a plurality of LED elements and radiating light to the irradiation target from a second direction orthogonal to the first direction;
A light blocking unit disposed to face the light source unit and sandwiching the transport path of the object to be irradiated, and blocking the light irradiated from the light source unit so that the light is not leaked to the outside.
to provide,
The light blocking unit
a light absorbing member that absorbs the light emitted from the light source unit;
a housing accommodating and supporting at least a portion of the light absorbing member;
A wind tunnel formed between the housing and the light absorbing member and through which cooling wind flows
has,
The light irradiation device according to claim 1 , wherein the light absorbing member has a box-shaped shape having an opening on the conveying path side, and is attached to the housing with a predetermined gap in the first direction between the light absorbing member and the housing. 2. The method of claim 1 , wherein the light absorbing member has a box-shaped shape having an opening on the transport path side, and is attached to the housing at a predetermined distance from the housing in a first direction. light irradiation device. 3. The method of claim 2 , wherein the light absorbing member has a box-shaped shape having an opening on the conveying path side, and is attached to the housing with a predetermined gap between the light absorbing member and the housing in the first direction. light irradiation device. 4. The method of claim 3 , wherein the light absorbing member has a box shape having an opening on the conveying path side, and is attached to the housing with a predetermined gap between it and the housing in the first direction. light irradiation device. 5. The method of claim 4, wherein the light absorbing member has a box shape having an opening on the conveying path side, and is attached to the housing with a predetermined gap between it and the housing in the first direction. light irradiation device. 6. The light irradiation device according to claim 5, wherein the light absorbing member has black electroless nickel plating or chrome plating on an inner surface. 7. The light irradiation device according to claim 6, wherein the light absorbing member has black electroless nickel plating or chrome plating on an inner surface. 8. The light irradiation device according to claim 7, wherein the light absorbing member has black electroless nickel plating or chrome plating on an inner surface. 9. The light irradiation device according to claim 8, wherein the light absorbing member has black electroless nickel plating or chrome plating on an inner surface. 10. The light irradiation device according to claim 9, wherein the light absorbing member has black electroless nickel plating or chrome plating on an inner surface. The light irradiation device according to any one of claims 1 to 14, wherein one end of the light source unit and the light blocking unit are connected via a hinge. The light irradiation device according to any one of claims 1 to 14, wherein the light emitted from the light source unit is ultraviolet light. 16. The light irradiation device according to claim 15, wherein the light emitted from the light source unit is ultraviolet light. delete

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