KR20200103540A - Light illuminating apparatus - Google Patents

Abstract

Provided is a light irradiating device which can reliably prevent ultraviolet rays from being leaked to the outside, and can prevent heat generation of a housing. The light irradiating device for irradiating an object to be irradiated, which is conveyed in a first direction, with light, comprises: a light source unit having a plurality of LED elements and irradiating an object to be irradiated with light from a second direction orthogonal to a first direction; and a light-shielding unit into which a conveying path of the object to be irradiated is fitted, and which is disposed to face the light source unit and shields the light irradiated from the light source unit not to be leaked to the outside. The light-shielding unit includes: a light absorbing member for absorbing the light irradiated from the light source unit; a housing for 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 and having cooling wind flowing therethrough.

Description

Light irradiation device {LIGHT ILLUMINATING APPARATUS}

The present invention relates to a light irradiation apparatus that irradiates light to a conveyed irradiation object.

BACKGROUND ART Conventionally, a printing apparatus for performing printing using UV ink cured by irradiation with ultraviolet light is known. In such a printing apparatus, after ink is ejected from the nozzle of the head onto the medium, the dots formed on the medium are irradiated with ultraviolet light. Since the dots are hardened by irradiation of ultraviolet light and fixed to the medium, good printing can be performed even on a medium that is difficult to absorb liquid.

In the ultraviolet light irradiation device used in such a printing device, from the recent request for reduction of power consumption, long lifespan, and compactness of the device size, it is preferable to use an LED (Light Emitting Diode) element as a light source instead of a conventional discharge lamp. It is provided for practical use (for example, Patent Document 1).

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

Japanese Unexamined Patent Publication No. 2018-118499

According to the configuration of Patent Document 1, since ultraviolet light is irradiated to the work passing through the work arrangement space (that is, the space in the housing), the ultraviolet rays are temporarily prevented from leaking out of the work arrangement space. However, when ultraviolet rays are irradiated in a closed space called the work arrangement space, it is difficult to completely prevent the ultraviolet rays from leaking out of the work arrangement space because the ultraviolet rays reflect at various places such as the housing part or the work itself. . In addition, when ultraviolet rays are applied to the housing portion in the work arrangement space, the housing heats up and there is a problem that the housing cannot be contacted.

The present invention has been made in view of such circumstances, and an object thereof is to provide a light irradiation device that reliably prevents ultraviolet rays from leaking out of the light irradiation device and also prevents heat generation of the housing.

In order to achieve the above object, the light irradiation device of the present invention is a light irradiation device for irradiating light to an irradiation object conveyed along a first direction, and has a plurality of LED elements, and a second direction orthogonal to the first direction A light source unit that irradiates light to an object to be irradiated from the light source unit, and a light shielding unit disposed opposite to the light source unit by inserting a conveyance path of the object to be irradiated, and shielding light so that the light irradiated from the light source unit does not leak to the outside, and the light shielding unit A light absorbing member for absorbing light irradiated from the light source unit, a housing for 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 and through which cooling wind flows.

According to such a configuration, since the light shielding unit absorbs light irradiated from the light source unit by the light absorbing member, ultraviolet rays are prevented from leaking out of the light irradiation device. In addition, since cooling wind flows between the housing and the light absorbing member, heat generation of the light shielding unit is also prevented.

In addition, it is preferable that the housing has a box-like shape having an opening on the side of the conveying path, 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. In this case, it is preferable that the housing has a second intake port for introducing air into the wind tunnel from the outside at one end of the first direction and a third direction orthogonal to the second direction.

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

In addition, it is preferable that the light absorbing member has a box-shaped shape having an opening on the side of the conveying path, and is attached to the housing at a predetermined interval between it and the housing. In this case, it is preferable that the light absorbing member has black electroless nickel plating or chromium plating on the inner surface.

Moreover, it is preferable that one end of the light source unit and the light shielding unit are 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 ultraviolet rays from leaking out of the light irradiation device and also prevents heat generation of the housing is realized.

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

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In addition, the same reference numerals are attached to the same or corresponding parts of the drawings, and the description is not repeated.

1 is a diagram showing a 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. Further, FIG. 2 is a cross-sectional view taken along line B-B in FIG. 1(b), and FIG. 3 is a cross-sectional view taken along line A-A in 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 object P (for example, a recording medium), and the irradiation object ( It is comprised of the light source unit 10 arrange|positioned above P), and the light shielding unit 20 arrange|positioned opposite to the light source unit 10 by sandwiching the conveyance path 40 of the irradiation object P. In addition, in this specification, the longitudinal direction of the line-shaped ultraviolet light emitted from the light source unit 10 is the X-axis direction, the conveying direction of the irradiated object P is the Y-axis direction, and the X-axis and the direction orthogonal to the Y-axis are the Z-axis. It is defined and explained in the direction.

As shown in FIGS. 2 and 3, the light source unit 10 is a device that emits line-shaped ultraviolet light along the X-axis direction, and 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 metal box-shaped housing having an opening in the bottom surface (the lower surface in Figs. 1 to 3), and a glass window member 12 is inserted into the opening in the bottom surface (Fig. 2, 3). Further, a pair of light shielding plates 17 are disposed on the bottom surface of the case 11 of the present embodiment so as to sandwich the window member 12. Each light shielding plate 17 is a rectangular plate-shaped metal member defined in the X-axis direction and the Y-axis direction, and is attached to protrude from the case 11 in a Y-axis direction and a direction 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 in the Z-axis direction) is subjected to black electroless nickel plating or chrome plating, so that ultraviolet light from the light source unit 10 Even if it touches and reflects this irradiation target object P, each light shielding plate 17 absorbs this reflected light, and is comprised so that it may not leak to the outside of the light irradiation apparatus 1.

The substrate 13 is a rectangular wiring board defined in the X-axis direction and the Y-axis direction, formed of a material having high thermal conductivity (for example, 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, for example, 150 (X-axis direction) × 4 rows (Y-axis direction), and COB ( Chip On Board) is installed. On the substrate 13, an anode pattern (not shown) and a cathode pattern (not shown) for supplying power to each LED element 14 are formed, so that each LED element 14 has an anode pattern and a cathode pattern. Each is electrically connected. In addition, the substrate 13 is electrically connected to a driver circuit (not shown) by a wiring cable not shown, so that a driving current is supplied from the driver circuit to each LED element 14 through an anode pattern and a cathode pattern. have. When a driving current is supplied to each LED element 14, ultraviolet light (e.g., wavelength 365 nm) of the amount of light according to the driving current is emitted from each LED element 14, and the X-axis from the light source unit 10 Ultraviolet light on a line parallel to the direction is emitted. In addition, the driving current supplied to each LED element 14 is adjusted so that each LED element 14 of the present embodiment emits an approximately uniform amount of ultraviolet light, and the ultraviolet light on a line emitted from the light source unit 10 is adjusted. Has an approximately uniform distribution of light quantity in the X-axis direction.

The cooling device 15 is disposed so as to be in close contact with the rear surface of the substrate 13 and is a so-called air-cooled heat sink that radiates heat generated from each LED element 14. The cooling device 15 is provided with 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, and a plurality of heat dissipating fins 16 are provided by airflow generated by the cooling fan. The radiating fins 16 are uniformly cooled.

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

4 and 5 are views for explaining the configuration of the light shielding unit 20 of the present embodiment, and FIG. 4 is a cross-sectional view taken along line C-C in FIG. 1(b), and FIG. 5 is an exploded perspective view. In addition, in FIG. 5, the light shielding plate 27 is omitted for convenience of explanation. As shown in Figs. 2 and 3, the light blocking unit 20 is disposed opposite the light source unit 10 with the conveying path 40 therebetween, so that the ultraviolet light emitted from the light source unit 10 does not leak to the outside. It is a device that blocks light. 3, the light shielding 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 in the X-axis direction of the light shielding unit 20 It is configured to be movable in the direction of rotation around the part. As described above, in the present embodiment, since the light shielding unit 20 moves in the rotational direction, the gap between the light shielding unit 20 and the light source unit 10 is opened, so that the irradiation target P such as continuous paper is It becomes possible to install easily in the conveyance path 40.

2 to 5, the light shielding unit 20 includes a light absorbing member 22 and a case 21 (housing) that accommodates and supports the light absorbing member 22. The case 21 is a box-shaped metal member having an opening 21e on the side of the conveying path 40, and a light absorbing member 22 is provided on the side plates 21a and 21b of the case 21 facing in the Y-axis direction. A plurality of through-holes (21g) for fixing the is formed, the side plate (21c) in the X-axis direction of the case 21 is formed with an intake port (21f) for introducing air from the outside, and the side plate facing the side plate (21c) An exhaust fan 30 for exhausting the air in the case 21 to the outside is disposed at 21d. In addition, as shown in FIGS. 2 and 4, a pair of light shielding plates 27 are provided on the side plates 21a and 21b of the case 21 of the present embodiment. Each light shielding plate 27 is a member of a metal rod 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. It is attached to (the side opposite to the Z-axis direction). Black electroless nickel plating or chromium plating is applied to the surface facing the light shielding plate 17 of the flat portion 27a of each light shielding plate 27 (that is, the surface opposite to the Z-axis direction). Even if the ultraviolet light from the unit 10 is reflected in the light-shielding unit 20, the light-shielding plate 27 absorbs the reflected light, so that it does not 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 side of the conveying path 40, and a plurality of side plates 22a, 22b of the light absorbing member 22 facing in the Y-axis direction The cylindrical boss material 23 of is attached. In addition, the upper side of the side plates 22c and 22d of the light absorbing member 22 facing in the X-axis direction (the side opposite to the Z-axis direction) protrudes upward from the side plates 22a and 22b, and this protrusion is more than the lower side. It is wide, and steps 22f and 22g are formed, respectively. As shown in FIG. 5, the light absorbing member 22 of this embodiment is inserted and attached to the opening 21e of the case 21. When the light absorbing member 22 is inserted into the opening 21e of the case 21, the stepped portions 22f, 22g of the side plates 22c, 22d become the upper side (Z) of the side plates 21a, 21b of the case 21 The side opposite to the axial direction) abuts against the cross section and is positioned in the Z-axis direction. And at this time, the position of each boss material 23 and the position of each through hole 21g coincide, and it is fixed to the case 21 by a fixing screw (not shown) inserted through each through hole 21g. (Fig. 4, Fig. 5). When the light absorbing member 22 is fixed in 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, the side plate 21b and the side plate 22b) ), and between the bottom plate 21h and the bottom plate 22h), a space S is formed (Fig. 2).

On the inner surface of the light absorbing member 22 of the present embodiment, black electroless nickel plating or chromium plating for absorbing ultraviolet light from the light source unit 10 is applied, as indicated by the dotted arrows in FIG. Similarly, ultraviolet light from the LED element 14 is made to enter between the side plate 22a and the side plate 22b. Therefore, even if the irradiation target P is cut off in the middle, the ultraviolet light from the light source unit 10 hits the light absorbing member 22 and is absorbed, and does not leak to the outside of the light irradiation device 1. In addition, as indicated by the dotted arrow in FIG. 3, in this embodiment, in order to uniformly irradiate the irradiation target P, the irradiation width in the X-axis direction of the light source unit 10 is the X-axis of the irradiation target P Although it is configured so as to be longer than the width in the direction, ultraviolet light that does not reach the irradiation target P is also absorbed by contacting the light absorbing member 22 so as not to leak to the outside of the light irradiation device 1.

As described above, in this embodiment, the light shielding unit 20 is disposed opposite the light source unit 10 with the conveying path 40 interposed therebetween, so that the ultraviolet light emitted from the light source unit 10 does not leak to the outside. have. However, when ultraviolet light from the light source unit 10 is irradiated onto the light shielding unit 20 in this way, there is a problem that the temperature of the light shielding unit 20 itself rises. Therefore, in this embodiment, in order to solve such a problem, a space S is formed between the light absorbing member 22 and the case 21, and a 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 on the side plate 21c of the case 21, and the air in the space S is supplied to the side plate 21d of the case 21. An exhaust fan 30 that exhausts to the outside is arranged so that cooling wind flows through the space S. That is, the space S is intended to function 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, the inside of the space S becomes negative pressure, and the gap between the light absorbing member 22 and the case 21 (first intake port) Air is received in the space S by passing through (refer to the solid arrow in FIG. 2 ), and is exhausted from the exhaust fan 30 by flowing through the space S in the X-axis direction. Further, when the exhaust fan 30 rotates and the air in the space S is exhausted to the outside, the air is also received in the space S from the intake port 21f (the second intake port) (refer to the solid arrow in FIG. 3), The inside of the space S flows in the X-axis direction and is exhausted from the exhaust fan 30. In this way, in the light shielding unit 20 of the present embodiment, by forming a wind tunnel between the light absorbing member 22 and the case 21, the light absorbing member 22 serving as a heat source is intensively cooled. In addition, 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 through the boss material 23), the light absorbing member The heat resistance between the case 22 and the case 21 is increased, so that the heat of the light absorbing member 22 is not transmitted to the case 21.

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

For example, the light shielding 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 in the X-axis direction of the light shielding unit 20 Although it was configured to be movable in the rotational direction with the portion as the center, it is not limited to such a configuration. The light blocking unit 20 and the light source unit 10 may be integrally configured, or may be configured such that the light blocking unit 20 and the light source unit 10 are separated along the Z-axis direction.

In addition, it is assumed that black electroless nickel plating or chromium plating, which absorbs ultraviolet light from the light source unit 10, is applied on the inner surface of the light shielding unit 20 of the present embodiment. A member that absorbs ultraviolet light may be attached to the inner surface of the unit 20.

Moreover, although the light absorbing member 22 of this embodiment is supposed to be 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 to form a wind tunnel through which cooling wind flows between the light absorbing member 22 and the case 21, and any other method may be applied.

(Modification 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 modification is different from the configuration of the light irradiation device 1 of this embodiment in that the shape of the light absorbing member 22A accommodated in the light shielding unit 20A is different.

More specifically, as shown in Fig. 6, in the light absorbing member 22A of this modification, the upper ends of the side plates 22a and 22b are bent outwardly (i.e., in a direction opposite to the Y-axis direction and the Y-axis direction), A pair of flat portions 22z are formed to face (17). In addition, the surface of the flat portion 22z facing the light shielding plate 17 was subjected to black electroless nickel plating or chrome plating, so that ultraviolet light from the light source unit 10 was reflected in the light shielding unit 20. It is comprised so that this reflected light may be absorbed by the sea-island part 22z so that it may not leak to the outside of the light irradiation apparatus 1A.

That is, in the light absorbing member 22A of the present modified example, a configuration corresponding to the planar portion 27a (Fig. 2) of the light shielding plate 27 of the present embodiment (that is, a 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 flat portions 22z face the light shielding plate 17. For this reason, according to this modification, it is not necessary to separately install the light shielding plate 27, and it is superior to the configuration of this embodiment in that the assembly process is simplified.

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

One… Light irradiation device
1A... Light irradiation device
10… Light source unit
11... case
12... No window
13... Board
14... LED element
15... Cooling system
16... Radiating fin
17... Shading plate
20… Shading unit
20A... Shading unit
21... case
21a... shroud
21b... shroud
21c... shroud
21d... shroud
21e... Opening
21f... 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... Step
22g... Step
22h... Bottom plate
22z... Flat part
23... Boss
27... Shading plate
27a... Flat part
30... Exhaust fan
40… Return route
50… Hinge
P… Investigation object
S… space

Claims (8)

A light irradiation device that irradiates light to an irradiation object conveyed along a first direction,
A light source unit having a plurality of LED elements and irradiating light to the irradiated object from a second direction orthogonal to the first direction,
A light-shielding unit that inserts the conveyance path of the object to be irradiated and is disposed opposite to the light source unit, and blocks light so that light irradiated from the light source unit does not leak to the outside
And,
The shading unit is
A light absorbing member for absorbing light irradiated 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 flowing cooling wind
Light irradiation device, characterized in that it has a. The housing according to claim 1, wherein the housing has a box-shaped shape having an opening on the conveying 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. Light irradiation device. The light irradiation apparatus according to claim 2, wherein the housing has a second intake port for introducing air into the wind tunnel from outside at one end of the first direction and a third direction orthogonal to the second direction. The light according to claim 2 or 3, wherein the housing has an exhaust fan at the other end of the first direction and a third direction orthogonal to the second direction to exhaust the air in the wind tunnel to the outside. Irradiation device. The method according to any one of claims 1 to 4, wherein the light absorbing member has a box-shaped shape having an opening on the side of the conveyance path, and is attached to the housing with a predetermined distance between the housing. Light irradiation device, characterized in that there is. The light irradiation apparatus according to claim 5, wherein the light absorbing member has black electroless nickel plating or chromium plating on its inner surface. The light irradiation apparatus according to claim 1, wherein one end of the light source unit and the light shielding unit is connected through a hinge. The light irradiation apparatus according to any one of claims 1 to 7, wherein the light emitted from the light source unit is ultraviolet light.

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