JP2008173968A - Ultraviolet irradiation device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ultraviolet irradiation device that can prevent thermal accumulation uniformly with respect to a plurality of ultraviolet light sources without upsizing the device, nor increasing the cost or consumption power, and can prevent lowering of a light emission coefficient of each of the ultraviolet light sources due to the thermal accumulation. <P>SOLUTION: This ultraviolet irradiation device 90 comprises the plurality of ultraviolet light sources 95 for emitting ultraviolet rays, and a circuit board 91 that supports the plurality of ultraviolet light sources 95 and is provided with electric wires 91b for energizing the ultraviolet light sources 95. A heat sink member 97 is provided between an element body 95a of each of the ultraviolet light sources 95 and the circuit board 91 to be in close contact with both of them. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an ultraviolet irradiating device including a plurality of ultraviolet light sources that emit ultraviolet light, and a circuit board that supports the plurality of ultraviolet light sources and includes electrical wiring for supplying power to the ultraviolet light sources. It is.

In recent years, ultraviolet curable inks have attracted attention as inks used in inkjet printers and the like.
UV curable ink differs from normal water-based ink or oil-based ink in that it adheres to a recording medium (printing paper), etc., and then quickly cures when irradiated with an appropriate amount of ultraviolet light, thereby recording ink such as ink permeability. This is the point that stable printing quality can be maintained without being influenced by the physical properties.
In an ink jet recording apparatus (ink jet printer) using such an ultraviolet curable ink, the ultraviolet curable ink is ejected as fine ink droplets and adhered to the recording medium around the recording head. It is necessary to equip the ink with an ultraviolet irradiation device for irradiating the ink with ultraviolet rays.

  By the way, in an ultraviolet irradiation device, an ultraviolet lamp such as a mercury lamp or a metal halide lamp is equipped as a light source that emits ultraviolet light. However, these light sources have a high heat generation temperature during light emission, and the heat generated by the light source generates heat around the light source. If the heat is stored, the light emission rate of the ultraviolet lamp decreases due to the high temperature due to the heat stored around the light source, resulting in a problem that the curing performance with respect to ink decreases or the life of the lamp decreases.

  In view of this, a conventional ultraviolet irradiation device has been proposed in which a water cooling device for cooling the periphery of the light source is provided. However, the water-cooling apparatus has a problem that the apparatus is easily increased in size and is difficult to be used for an ink jet recording apparatus in which downsizing is an important issue. In addition, there is also a problem that the ultraviolet irradiation device is expensive due to the water cooling device.

From such a background, there has been proposed an ultraviolet irradiation device having a configuration in which a Peltier element for cooling is disposed in the vicinity of the ultraviolet light source and heat storage around the ultraviolet light source is prevented by the Peltier element (for example, Patent Document 1). And Patent Document 2).
That is, by using such a Peltier element as a cooling means, it is possible to reduce the size of the apparatus rather than using a water cooling apparatus.

JP 2004-237603 A JP 2005-231235 A

By the way, in recent ultraviolet irradiation apparatuses for ink jet recording apparatuses, a plurality of ultraviolet light sources are arranged side by side in a predetermined plane or curved surface so as to eliminate variations in irradiation intensity in the ultraviolet irradiation region. Proposed.
However, in such an ultraviolet irradiation device using a plurality of ultraviolet light sources, it is difficult to obtain sufficient cooling performance by the above-described cooling mechanism using the Peltier element.

That is, in order to cool each ultraviolet light source evenly, it is desirable to equip each ultraviolet light source with a cooling Peltier element. However, if this is done, the number of equipped Peltier elements becomes large and the apparatus becomes larger. At the same time, the manufacturing cost increases.
In addition, since the number of Peltier elements to be installed increases, the power consumption in the ultraviolet irradiation device increases, and there is a problem that it is impossible to meet the demand for power saving in the ink jet recording apparatus and the like.

  Accordingly, an object of the present invention is to solve the above-mentioned problems and prevent heat storage evenly for a plurality of ultraviolet light sources without increasing the size of the apparatus, increasing costs, and increasing power consumption. It is an object of the present invention to provide an ultraviolet irradiation device that can prevent a decrease in the light emission rate in an ultraviolet light source due to the above.

The above object of the present invention is to irradiate ultraviolet rays comprising a plurality of ultraviolet light sources that emit ultraviolet rays, and a circuit board that supports the plurality of ultraviolet light sources and includes electrical wiring for supplying power to these ultraviolet light sources. A device,
This is achieved by an ultraviolet irradiation device characterized in that a heat radiating member that is in close contact with both is provided between the light source portion of each ultraviolet light source and the circuit board.

According to the ultraviolet irradiation device having the above configuration, the heat generated by the light emitting portion of each ultraviolet light source is radiated from the circuit board via the closely radiating member and the heat radiating member, so that heat is not stored around the ultraviolet light source. .
The heat dissipation member is a material that exhibits a heat dissipation effect due to its material heat transfer characteristics, and may be equipped with a simple form such as a spacer that fills the gap between the light source part of the ultraviolet light source and the circuit board. And requires less installation space. Also, unlike an electrical cooling means such as a Peltier element, no power supply is required.
Therefore, heat storage is uniformly prevented for a plurality of ultraviolet light sources without causing an increase in size, cost, and power consumption of the ultraviolet irradiation device, and a decrease in the light emission rate in the ultraviolet light source due to heat storage is prevented. be able to.

  In the ultraviolet irradiation device having the above configuration, the heat dissipation member has a thickness dimension that fills a gap between the light source portion of the ultraviolet light source and the circuit board, and is laminated on the circuit board. It is desirable that

  According to the ultraviolet irradiation device having such a configuration, the heat radiation member is individually provided for the plurality of ultraviolet light sources by providing the sheet-like heat radiation member so as to cover the surface of the circuit board to which the plurality of ultraviolet light sources are attached. This eliminates the need for assembling them one by one, and simplifies the manufacturing process, thereby reducing costs and improving productivity.

  Moreover, in the ultraviolet irradiation apparatus having the above-described configuration, the sheet-like heat radiation member is a heat conductive gel having a surface that contacts the light source portion of the ultraviolet light source having electrical insulation, flexibility, and adhesiveness. Is desirable.

  According to the ultraviolet irradiation device having such a configuration, it is possible to easily obtain a state in which the sheet-like heat radiating member is in close contact with the light source portion of the ultraviolet light source without any gaps due to the physical properties of the heat conductive gel such as flexibility and adhesiveness. It is possible to improve the heat dissipation effect from the light source part to the sheet-like heat radiating member by improving the adhesion, and further reduce the heat storage of the ultraviolet light source and its surroundings.

  Moreover, in the ultraviolet irradiation device having the above-described configuration, it is desirable that the sheet-like heat radiation member is a graphite sheet provided with an insulating layer.

  According to the ultraviolet irradiation device having such a configuration, the high thermal conductivity and flexibility of the graphite sheet enhances the heat radiation effect from the light source part to the sheet-like heat radiation member, further reducing the heat storage of the ultraviolet light source and its surroundings. can do.

  In the ultraviolet irradiation apparatus having the above-described configuration, the ultraviolet light source is preferably at least one selected from a mercury lamp, a metal halide lamp, a xenon lamp, an excimer lamp, an LED, and an LD.

  According to the ultraviolet irradiation device having such a configuration, in each ultraviolet light source used, it is possible to prevent a decrease in light emission rate due to heat storage, and it is possible to realize stable ultraviolet irradiation in each ultraviolet light source.

  Moreover, it is preferable that the ultraviolet irradiation device having the above-described configuration includes a heat dissipation mechanism that dissipates heat transmitted to the heat dissipation member.

  According to the ultraviolet irradiation device having such a configuration, heat transmitted from the ultraviolet light source, which is a heat generation source, to the heat radiating member can be efficiently radiated to the outside, and heat storage in the ultraviolet light source and its surroundings can be further reduced.

  In the ultraviolet irradiation device having the above-described configuration, it is preferable that a hole is provided at a predetermined position of the heat dissipation member as the heat dissipation mechanism so as to increase a contact area between the heat dissipation member and air.

According to the ultraviolet irradiation device having such a configuration, the contact area between the heat radiating member and the air can be increased, and the heat transmitted from the ultraviolet light source, which is a heat generation source, to the heat radiating member can be radiated more efficiently into the air. .
In addition, the “hole” herein may be a hole that increases the contact area between the heat radiating member and air, and may be a through-hole or an opening that does not penetrate.

  Moreover, in the ultraviolet irradiation device having the above-described configuration, it is desirable that the heat radiation mechanism is provided with a through-hole that contacts the heat radiation member and air at a predetermined position of the circuit board that is in close contact with the heat radiation member.

  According to the ultraviolet irradiation device having such a configuration, the contact area between the heat radiating member and the air can be increased, and the heat transmitted from the ultraviolet light source, which is a heat generation source, to the heat radiating member can be radiated more efficiently into the air. . Further, since the contact surface of the circuit board with the air also increases, the heat transferred to the circuit board can be efficiently dissipated into the air.

  Moreover, in the ultraviolet irradiation device having the above configuration, it is desirable that a fan is provided as the heat dissipation mechanism.

  According to the ultraviolet irradiation device having such a configuration, the amount of air movement can be increased by blowing air from the fan, and the heat transmitted to the heat radiating member can be radiated more efficiently into the air.

  Moreover, in the ultraviolet irradiation device having the above-described configuration, it is preferable that a part of the heat radiating member is further in close contact with another heat radiating member as the heat radiating mechanism.

According to the ultraviolet irradiation apparatus having such a configuration, the heat transmitted to the heat radiating member can be radiated more efficiently, and the heat storage of the ultraviolet light source and its surroundings can be further reduced.
As said other heat radiating member, installation type heat radiating members, such as a heat sink, are mentioned. For example, when a graphite sheet is used as the heat radiating member, the thermal conductivity in the in-plane direction of the graphite sheet is equal to or higher than that of the metal, but the thermal conductivity in the thickness direction is higher than the thermal conductivity in the in-plane direction. Inferior. Therefore, by installing a heat radiating member such as a heat sink so as to be in close contact with a part of the extended graphite sheet, the heat generated in each ultraviolet light source is soaked in the in-plane direction by the graphite sheet, and the graphite The heat is efficiently radiated into the air through a heat radiating member such as a heat sink disposed in close contact with the sheet.
On the other hand, even if a heat sink or the like is not installed as described above, heat is dissipated by disposing a part of the heat radiating member such as the graphite sheet so as to be in close contact with another highly heat conductive member such as a metal frame in the ultraviolet irradiation device. You may let them.

  Further, in the ultraviolet irradiation apparatus having the above-described configuration, the ultraviolet curable ink that is provided in an ink jet recording apparatus that includes a recording head that ejects ultraviolet curable ink onto a recording medium, and is attached to the recording medium by the recording head. It is desirable to irradiate UV rays.

  According to the ultraviolet irradiation apparatus having such a configuration, it is possible to prevent a decrease in light emission efficiency for each ultraviolet light source and to realize stable ultraviolet irradiation with no variation in irradiation intensity over the entire ultraviolet irradiation region. Therefore, it is possible to improve the recording performance by reducing the variation in the curing time of the ultraviolet curable ink in the ink jet recording apparatus.

Hereinafter, an ultraviolet irradiation device according to a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 is a schematic perspective view showing a main configuration of an inkjet printer 20 equipped with an ultraviolet irradiation device according to a first embodiment of the present invention.

  As shown in FIG. 1, the inkjet printer 20 of the present embodiment has a paper feed motor 30 that feeds printing paper P as a recording medium in the sub-scanning direction SS, a platen 40, and ultraviolet curable ink with a small particle size. A print head 52 as a recording head to be attached to the print paper P, a carriage 50 on which the print head 52 is mounted, a carriage motor 60 that moves the carriage 50 in the main scanning direction MS, and UV curable ink by the print head 52. An ultraviolet irradiation device 90 for irradiating ultraviolet rays onto the ink adhesion surface on the attached printing paper P is provided.

The carriage 50 is pulled by a pulling belt 62 driven by a carriage motor 60 and moves along a guide rail 64. In addition to the print head 52, the carriage 50 has a black cartridge 54 as a black ink container that contains black ink supplied to the print head 52, and a color ink container that contains color ink supplied to the print head 52. The color ink cartridge 56 is mounted.
The ink stored in each cartridge 54, 56 is a so-called ultraviolet curable ink.

  A capping device 80 for sealing the nozzle surface of the print head 52 when stopped is provided at the home position of the carriage 50 (the position on the right side in FIG. 1). When the print job ends and the carriage 50 reaches above the capping device 80, the capping device 80 is automatically raised by a mechanism (not shown) to seal the nozzle surface of the print head 52. This capping prevents the ink in the nozzles from drying out. The positioning control of the carriage 50 is performed to accurately position the carriage 50 at the position of the capping device 80, for example.

  As shown in FIGS. 1 to 3, the ultraviolet irradiation device 90 of this embodiment includes a plurality of ultraviolet light sources 95 that emit ultraviolet light, a circuit board 91 that supports these ultraviolet light sources 95, and the circuit board 91 as a printer. Brackets 92 and 93 fixed to 20 housings, and an ultraviolet irradiation device drive circuit (not shown) for controlling the light emission and extinction of each ultraviolet light source 95 are provided.

The circuit board 91 has a predetermined width dimension W (see FIG. 2) along the sub-scanning direction SS of the printing paper P in the inkjet printer 20, and a predetermined length dimension L (see FIG. 1) along the main scanning direction MS. A plate-like structural material having a reference). The length dimension L is set larger than the width dimension of the maximum paper handled in the printer 20.
As shown in FIG. 3, the circuit board 91 is fixed to the casing of the inkjet printer 20 by brackets 92 and 93 with the mounting surface 91 a to which the ultraviolet light source 95 is attached facing the surface of the printing paper P. . The circuit board 91 is a printed circuit board on which an electric wiring pattern 91b for supplying power to each ultraviolet light source 95 is printed on the surface opposite to the mounting surface 91a.
Further, the mounting position of the circuit board 91 is a position away from the print head 52 forward (sub scanning direction SS) by a certain distance.

  The brackets 92 and 93 are fixed by screwing the end of the circuit board 91 to the housing of the printer 20 or by fitting the concave and convex portions.

In the present embodiment, as the ultraviolet light source 95, an ultraviolet light emitting diode (LED) that emits ultraviolet light in a predetermined wavelength band is used.
The ultraviolet light source 95 includes two lead wires (conduction portions) 95b and 95c extending from the element main body (light source portion) 95a, and through the through holes 91c formed through the circuit board 91. By soldering to 91b, electrical connection to the power supply circuit is made, and when power is supplied, ultraviolet rays 96 are emitted from the end face of the element body 95a as shown in FIG.

  In the case of the present embodiment, as shown in FIG. 3, the lead wires 95b and 95c of the ultraviolet light source 95 ensure a predetermined separation distance D between the mounting surface 91a of the circuit board 91 and the element body 95a. The length has been adjusted. And between the element main body 95a of each ultraviolet light source 95 and the mounting surface 91a of the circuit board 91, the heat radiating member 97 is provided so that the clearance gap of the above-mentioned separation distance D may be filled.

  The heat radiating member 97 of this embodiment is a sheet-like heat radiating member laminated on the circuit board 91 with a thickness that fills the gap between the element main body 95a of the ultraviolet light source 95 and the mounting surface 91a of the circuit board 91. .

  The sheet-like heat radiating member 97 is a sheet-like heat conducting gel that is uniformly provided with electrical insulation, flexibility, and adhesiveness. Specifically, a COH series sheet-like heat conductive gel manufactured by GELTEC is suitable.

According to the ultraviolet irradiation device 90 of the present embodiment described above, heat generated from the element main body 95a of each ultraviolet light source 95 is radiated from the circuit board 91 through the closely radiating member 97 and the circuit board 91. No heat is stored around the light source 95.
The heat radiating member 97 exhibits a heat radiating effect due to its material heat transfer characteristics, and is a spacer that fills the gap between the element body 95a of the ultraviolet light source 95 and the circuit board 91 as in the above embodiment. It can be equipped in such a simple form, and installation space is small. Also, unlike an electrical cooling means such as a Peltier element, no power supply is required.

  Accordingly, heat storage is uniformly prevented for the plurality of ultraviolet light sources 95 without increasing the size of the ultraviolet irradiation device 90, increasing costs, and increasing power consumption, and lowering the light emission rate in the ultraviolet light source 95 due to heat storage. Can be prevented.

  Further, in the case of the ultraviolet irradiation device 90 of the present embodiment, the heat radiating member 97 has a thickness dimension that fills the gap between the element main body 95 a of the ultraviolet light source 95 and the circuit board 91 and is laminated on the circuit board 91. It is a sheet-like heat dissipation member. Therefore, by installing a large sheet-like heat radiation member 97 so as to cover the surface of the circuit board 91 to which the plurality of ultraviolet light sources 95 are attached, one heat radiation member is individually provided for the plurality of ultraviolet light sources 95. Eliminating the time and effort of assembling one by one, and simplifying the manufacturing process can reduce costs and improve productivity.

  Further, in the case of the ultraviolet irradiation device 90 of the present embodiment, the heat radiating member 97 is a sheet-like heat conductive gel whose surface on the side in contact with the ultraviolet light source 95 has electrical insulation, flexibility and adhesiveness. . Therefore, the heat conducting gel has physical properties such as flexibility and adhesiveness, so that a state in which the heat radiating member 97 is in close contact with the element main body 95a of the ultraviolet light source 95 without gaps can be easily obtained. The heat radiation effect from the main body 95a to the heat radiating member 97 can be enhanced, and the heat storage of the ultraviolet light source 95 and its surroundings can be further reduced.

  Further, as shown in FIG. 4, the ultraviolet irradiation device 90 of the present embodiment preferably has a configuration in which an opening 97 a that increases the contact area with air is provided at a predetermined position of the heat dissipation member 97. With this configuration, the heat transmitted from the ultraviolet light source 95, which is a heat generation source, to the heat radiating member 97 can be radiated more efficiently into the air. The opening 97 a may be a hole that penetrates to the mounting surface 91 a of the circuit board 91. The number, arrangement, and shape of the openings 97a are not particularly limited and can be appropriately designed.

  As shown in FIG. 1, when the ultraviolet curable ink applied to the print paper P by the print head 52 in the inkjet printer 20 is irradiated by the ultraviolet irradiation device 90, ultraviolet irradiation is performed. In the apparatus 90, it is possible to prevent the emission efficiency of each ultraviolet light source 95 from being lowered and to realize stable ultraviolet irradiation with no variation in irradiation intensity over the entire ultraviolet irradiation region Q (see FIGS. 2, 5, and 7). Therefore, it is possible to reduce the variation in the curing time of the ultraviolet curable ink in the inkjet printer 20 and improve the recording performance.

  Note that the configurations of the ultraviolet light source, the circuit board, the heat radiating member, and the like in the ultraviolet irradiation device of the present invention are not limited to the configuration of the ultraviolet irradiation device 90 of the above-described embodiment, and various forms are possible based on the spirit of the present invention. Needless to say, it can be adopted. Hereinafter, an example of other embodiments of the ultraviolet irradiation device of the present invention will be described.

  As shown in FIGS. 5 to 6, the ultraviolet irradiation device 190 according to the second embodiment is the same ultraviolet irradiation device as that of the first embodiment described above. The through-hole 91d that contacts is provided. By providing the through hole 91d, the contact area between the heat radiation member 97 and the air can be increased, and the heat transmitted from the ultraviolet light source 95, which is a heat generation source, to the heat radiation member 97 can be radiated more efficiently into the air. Moreover, since the contact surface with the air of the circuit board 91 also increases, the heat transmitted to the circuit board 91 can be efficiently radiated into the air. The number, arrangement, and shape of the through holes 91d are not particularly limited, and can be appropriately designed.

As shown in FIG. 7, the ultraviolet irradiation device 290 according to the third embodiment is the same as the ultraviolet irradiation device as in the first embodiment described above, but the width dimension W2 of the heat radiating member 97 is larger than the width dimension W of the circuit board 91. It is a larger configuration. A heat sink is formed by placing a lightweight heat sink 100 such as aluminum in close contact with a portion 97b (extended portion of the heat dissipation member 97) that is not in close contact with the circuit board 91, which is a part of the heat dissipation member 97. The heat transmitted from the ultraviolet light source 95 to the heat radiating member 97 can be radiated more efficiently into the air. The heat sink 100 is preferably made of aluminum plates arranged at intervals of about 1 mm or less without being in close contact with each other.
In FIG. 7, the heat sink 100 is brought into close contact with the extended portion 97b of the heat radiating member 97, and a clearance is provided between the heat sink 100 and the circuit board 91. However, the heat sink 100 is configured to be a circuit board via an insulating member or the like. 91 may be brought into close contact. With such a configuration, heat transferred from the ultraviolet light source 95, which is a heat generation source, to the circuit board 91 can be radiated more efficiently into the air.
Even if the extended portion 97b of the heat radiating member 97 is brought into close contact with a metal frame (not shown) of the ultraviolet irradiation device 290 or a metal frame component (for example, the guide rail 64) of the ink jet printer, the ultraviolet light source 95 that is a heat source. The heat transmitted to the heat radiating member 97 can be efficiently radiated into the air.
Furthermore, by installing the fan 98 in the vicinity of the circuit board 91, the heat dissipation effect from the element body 95a can be further enhanced, and the heat storage in the ultraviolet light source 95 and its surroundings can be further reduced.

For example, the ultraviolet light source used in the ultraviolet irradiation device of the present invention is not limited to the ultraviolet light emitting diode (LED) shown in the above embodiment.
For example, instead of LEDs, mercury lamps, metal halide lamps, xenon lamps, excimer lamps, LDs, and the like can be used as the ultraviolet light source.
And even if any ultraviolet light source is used, the fall of the emitted light rate resulting from heat storage can be prevented, and stable ultraviolet irradiation can be implement | achieved in each ultraviolet light source.

In addition, the heat radiating member of the present invention is not limited to the one using the heat conductive gel as the sheet-like heat radiating member as described above, but can be variously attached to the light source part 95a and the circuit board 91 of each ultraviolet light source 95. The heat radiating member can be used.
For example, a sheet-like heat dissipation member such as a graphite sheet provided with a silicon sheet or an insulating layer can be used instead of the sheet-like heat conductive gel. The graphite sheet provided with an insulating layer such as silicon has high thermal conductivity and flexibility, and enhances the heat radiation effect from the light source portion 95a of each ultraviolet light source 95 to the sheet-like heat radiating member. The surrounding heat storage can be further reduced.
Further, a punching metal such as aluminum, copper, silver or iron having an opening corresponding to the element body 95a of the ultraviolet light source 95 is laminated on the mounting surface 91a of the circuit board 91, and the opening between the punching metal and the element body 95a is laminated. It is also possible to provide a heat radiating member in close contact with the light source portion 95a of each ultraviolet light source 95 and the circuit board 91 by filling a flexible electrically insulating member such as a heat conducting gel.

Furthermore, the equipment equipped with the ultraviolet irradiation device of the present invention is not limited to the ink jet printer of the above embodiment. It can be mounted on various devices that apply and cure ultraviolet curable liquid.
Various materials such as paper, film, cloth, and thin metal plate can be considered as the material of the recording medium irradiated with ultraviolet rays by the ultraviolet irradiation apparatus of the present invention.

1 is a schematic perspective view showing a main configuration of an ink jet printer equipped with an ultraviolet irradiation device according to a first embodiment of the present invention. It is an expansion perspective view of the ultraviolet irradiation device shown in FIG. It is AA sectional drawing of the ultraviolet irradiation device shown in FIG. It is AA sectional drawing of the modification of the ultraviolet irradiation device shown in FIG. It is an expansion perspective view which shows 2nd embodiment of the ultraviolet irradiation device mounted in the inkjet printer shown in FIG. It is AA sectional drawing of the ultraviolet irradiation device shown in FIG. It is an expansion perspective exploded view which shows 3rd embodiment of the ultraviolet irradiation device mounted in the inkjet printer shown in FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 20 ... Inkjet printer (inkjet recording device), 30 ... Paper feed motor, 32 ... Rotary encoder, 34 ... Paper feed roller, 40 ... Platen, 50 ... Carriage, 52 ... Print head (recording head), 54 ... Black cartridge, 56 ... Color ink cartridge, 60 ... Carriage motor, 62 ... Traction belt, 64 ... Guide rail, 80 ... Capping device, 90, 190, 290 ... UV irradiation device, 91 ... Circuit board, 91a ... Mounting surface, 91d ... Through-hole , 92, 93 ... bracket, 95 ... ultraviolet light source, 96 ... ultraviolet light, 97 ... heat radiating member, 97a ... opening, 97b ... extended portion of heat radiating member 97, 98 ... fan, 100 ... heat sink, P ... printing paper (recording medium) ), SS: sub-scanning direction, MS: main scanning direction.

Claims (11)

An ultraviolet irradiation device comprising: a plurality of ultraviolet light sources that emit ultraviolet light; and a circuit board that supports the plurality of ultraviolet light sources and includes electrical wiring that supplies power to these ultraviolet light sources,
An ultraviolet irradiation device, wherein a heat radiating member that is in close contact with both is provided between a light source portion of each ultraviolet light source and the circuit board.   The heat dissipation member is a sheet-like heat dissipation member having a thickness dimension that fills a gap between the light source portion of the ultraviolet light source and the circuit board, and is laminated on the circuit board. The ultraviolet irradiation device described in 1.   The ultraviolet irradiation device according to claim 2, wherein the sheet-like heat radiation member has a surface that is in contact with the light source portion of the ultraviolet light source, which is a heat conductive gel.   The ultraviolet irradiation device according to claim 2, wherein the sheet-like heat radiating member is a graphite sheet provided with an insulating layer.   5. The ultraviolet irradiation device according to claim 1, wherein the ultraviolet light source is at least one selected from a mercury lamp, a metal halide lamp, a xenon lamp, an excimer lamp, an LED, and an LD.   The ultraviolet irradiation device according to any one of claims 1 to 5, further comprising a heat dissipation mechanism that dissipates heat transmitted to the heat dissipation member.   The ultraviolet irradiation device according to claim 6, wherein a hole is provided at a predetermined position of the heat dissipation member as the heat dissipation mechanism so as to increase a contact area between the heat dissipation member and air.   The ultraviolet radiation device according to claim 6, wherein the heat radiation mechanism is provided with a through-hole for contacting the heat radiation member and air at a predetermined position of the circuit board in close contact with the heat radiation member.   The ultraviolet irradiation device according to claim 6, further comprising a fan as the heat dissipation mechanism.   The ultraviolet irradiation device according to claim 6, wherein a part of the heat radiating member is further in close contact with another heat radiating member as the heat radiating mechanism.   It is equipped with an ink jet recording apparatus including a recording head that ejects ultraviolet curable ink onto a recording medium, and irradiates ultraviolet rays onto the ultraviolet curable ink adhered on the recording medium by the recording head. The ultraviolet irradiation device according to any one of claims 1 to 10.

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