JP2005081738A - Ultraviolet ray-irradiating apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ultraviolet ray-irradiating apparatus capable of effectively hardening an ultraviolet ray-curable resin with a relatively small amount of a gas. <P>SOLUTION: In the ultraviolet ray-irradiating apparatus, a discharging hole 39 is formed on a light-transmissive plate 34a on a work side through which ultraviolet ray from the ultraviolet ray-irradiating portion 12 passes, and the circumference of the opening on the work side of the discharging hole 39 is constructed to be a wall of the transparent plate 34a on the work side (or the plate 34a on the work side and a frame 31). In another word, the wall is mounted in the circumference of the discharging hole 39 to prevent (suppress) the surrounding air from being included. This prevents (suppresses) the surrounding air from being included, differently from the prior art wherein nitrogen is supplied from a nozzle extending from a side of a housing. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an ultraviolet irradiation device that irradiates a workpiece with ultraviolet rays.

As this type of ultraviolet irradiation device, for example, as shown in Patent Document 1 below, the ultraviolet curing property provided on the workpiece by irradiating the workpiece with ultraviolet rays is provided above the irradiation chamber in which the workpiece is conveyed. Some are used to cure a resin (hereinafter “UV resin”). By the way, in the state where UV resin is exposed to an air atmosphere containing oxygen even if it is irradiated with ultraviolet rays, surface curing failure is caused by so-called oxygen inhibition, so that an inert gas atmosphere such as nitrogen or carbon dioxide is usually used. It is desirable to irradiate with ultraviolet rays. FIG. 5 shows a conventional configuration in which the workpiece 1 is irradiated with ultraviolet rays while blowing nitrogen. As shown in the figure, the housing 3 that accommodates the ultraviolet lamp 2 is provided with an irradiation window 4 in which the opening on the lower surface is sealed with a glass plate, from which ultraviolet rays emitted from the ultraviolet lamp 2 (see FIG. Then, the dotted line arrow 7) is irradiated toward the machining part of the workpiece 1. A pair of nozzles 5 and 5 for discharging nitrogen (solid arrow 8 in the figure) are extended toward the work 1 on the side of the housing 3, and thereby the work 1 is applied to the work 1 in a nitrogen atmosphere. The irradiated UV resin 6 is irradiated with ultraviolet rays.
Japanese Patent Laid-Open No. 55-1815

  However, in the above-described conventional configuration, since nitrogen is blown onto the work 1 by the nozzles 5 and 5 extending from the side of the housing 3, the air flow of nitrogen is the atmosphere around the tip of the nozzles 5 and 5 (one point in FIG. 5). Since the broken line arrow 9) is involved, there is a problem that the oxygen concentration in the vicinity of the work 1 is increased and the UV resin 6 cannot be cured efficiently. Certainly, it is conceivable to reduce the oxygen concentration by increasing the amount of nitrogen supplied from the nozzles 5 and 5, but this requires a large amount of nitrogen and prevents the large amount of nitrogen from leaking outside. A configuration with a high hermeticity is required, which may cause a problem of high cost.

  The present invention has been completed based on the above circumstances, and an object of the present invention is to provide an ultraviolet irradiation device that can use a relatively small amount of gas.

As a means for achieving the above object, an ultraviolet irradiation apparatus according to the invention of claim 1 has a pair of light-transmitting wall portions arranged side by side with a space between the ultraviolet lamp and the workpiece. In addition, a gas supply unit for supplying gas is provided in a space sandwiched between the pair of translucent walls, so that ultraviolet rays from the ultraviolet lamp are transmitted through the pair of translucent walls and irradiate the workpiece. The translucent wall portion that is configured and disposed on the workpiece side is characterized in that a discharge hole that discharges gas to the workpiece side is formed.
The “workpiece” may be a member obtained by applying an ultraviolet curable resin to the member, or may be the ultraviolet curable resin itself.

  According to a second aspect of the present invention, the ultraviolet lamp is cooled by a cooling intake means according to the first aspect of the invention, and air around the gas supply section is sucked into the side of the gas supply section. It is characterized in that a restricting wall that restricts being pulled in by the means protrudes rearward.

According to a third aspect of the present invention, in the first or second aspect of the present invention, the work is conveyed so as to traverse the irradiation light path of the ultraviolet light from the ultraviolet lamp, and has the following configuration (a) or (b): It has features where it is provided.
(A) A configuration in which the discharge holes are formed only on the upstream side of the workpiece conveyance path from the irradiation center of the ultraviolet rays from the ultraviolet lamp.
(B) A configuration in which the discharge holes are formed on the upstream side and the downstream side with respect to the irradiation center, and more inert gas is discharged from the discharge holes on the upstream side than on the downstream side.

<Invention of Claim 1>
According to this configuration, ultraviolet rays from the ultraviolet lamp pass through a pair of translucent wall portions (wall portions capable of transmitting ultraviolet rays) of the gas supply unit to which gas is supplied, and are irradiated onto the workpiece. Is emitted toward the workpiece from the discharge hole formed in the light transmitting wall portion on the workpiece side. Therefore, the surrounding wall (including oxygen) due to the gas flow can be suppressed by the wall surface around the opening on the workpiece side of the discharge hole, and compared with the conventional configuration in which the gas is discharged from the nozzle extending to the side of the housing. A small amount of gas is sufficient.

<Invention of Claim 2>
In the structure in which the air around the ultraviolet lamp is cooled by the intake means for cooling, the air around the side of the gas supply section is drawn in by the intake means, and part of the air is supplied to the gas supply section. There is a risk that it will flow between the workpiece and the workpiece.
Therefore, according to this configuration, the restriction wall restricts the air around the gas supply unit side from being drawn in by the intake unit, so that the air around the gas supply unit side is blocked by the intake unit as described above. It is possible to prevent a part from flowing between the gas supply unit and the workpiece.

<Invention of Claim 3>
When the workpiece crosses the front of the gas supply part at a somewhat high speed, the gas emitted from the discharge hole is dragged to the downstream side of the transport path, so the upstream gas concentration is lower than the downstream concentration. To do. This is because, for example, when the discharge hole is formed at a position closer to the downstream side than the irradiation center of the ultraviolet ray from the ultraviolet lamp in the translucent wall, the gas is dragged further downstream by the work, and eventually the gas It means that the workpiece is irradiated with ultraviolet rays in a state where the concentration is lowered.
Therefore, in the present invention, one of the following configurations (a) and (b) is adopted.
(A) The discharge hole is formed only at a position upstream of the irradiation center of the ultraviolet ray from the ultraviolet lamp.
(B) A configuration in which the discharge holes are formed at positions upstream and downstream of the irradiation center, and more gas is discharged from the discharge holes on the upstream side than on the downstream side.
With such a configuration, even when the workpiece is conveyed at high speed, the workpiece can be irradiated with ultraviolet rays while suppressing a decrease in gas concentration.

An embodiment of the present invention will be described with reference to FIGS.
1. Overview of Ultraviolet Irradiation Apparatus The ultraviolet irradiation apparatus 10 according to the present embodiment is transported by a transport means 52 that sequentially transports a workpiece W (for example, flooring) that has been subjected to various types of processing using an ultraviolet curable resin (hereinafter “UV resin 50”). It arrange | positions on the path | route 51, and it irradiates an ultraviolet-ray, spraying nitrogen as gas to the workpiece | work W, and hardens the UV resin 50. FIG. In addition, the workpiece | work W shall be conveyed from the paper surface right to the left in FIG.

2. Configuration of Ultraviolet Irradiation Device FIGS. 1 to 3 are side views showing the entire ultraviolet irradiation device 10. As shown in the figure, the ultraviolet irradiation device 10 includes an ultraviolet emission unit 12 that accommodates an ultraviolet lamp (hereinafter referred to as “lamp 11”), and a gas supply unit that is provided below and supplies nitrogen to the internal space. 30.

(1) Ultraviolet emitting part The ultraviolet emitting part 12 has a rectangular parallelepiped shape as a whole, and a straight tubular lamp 11 is accommodated in a box-shaped case 13 whose one side faced toward the lower conveyance path 51 is open. The lamp 11 is held by fitting small diameter portions at both ends into through holes 14a and 14a of holding pieces 14 and 14 projecting downward from the ceiling inside the case 13 respectively. The lamp 11 is turned on when a voltage is applied from the terminal portion 15 provided on one end side of the case 13 via the cable 16 and emits ultraviolet rays radially. This ultraviolet ray is set to a wavelength suitable for UV resin curing (for example, a main wavelength of 365 nm).

  Further, a pair of reflecting mirrors 17 and 17 are arranged substantially rearward of the lamp 11 with respect to the opening direction of the case 13 (downward in FIG. 3). The reflecting mirrors 17 and 17 have a circular arc shape that covers the entire length of the upper side and the side of the lamp 11, and reflect the ultraviolet rays emitted rearward from the lamp 11 to guide them to the opening side (see FIG. 3, the optical path of the ultraviolet ray is indicated by a dotted arrow L). Each of the reflecting mirrors 17 and 17 has a lower end portion locked by grooves 13b and 13b provided inside the opening 13a of the case 13, and an upper end portion protruding downward from the ceiling surface inside the case 13. It is partially locked by the fixed fixture 20. And about the part in which the fixing tool 20 is not provided, the clearance gap S of the predetermined space | interval is formed between the upper end parts of both the reflective mirrors 17 and 17 (refer FIG. 3).

  A housing chamber 19 that houses a cooling fan 18 (corresponding to the “intake means” of the present invention) is provided at the center of the upper surface of the case 13. By driving the cooling fan 18, Air is drawn through the gap S between the pair of reflecting mirrors 17 and 17 and is discharged to the outside from an exhaust port 19 a opened on the upper surface of the storage chamber 19.

(2) Gas Supply Unit The gas supply unit 30 has a central portion that opens in a rectangular shape corresponding to the shape of the opening 13a of the case 13 and sandwiches the sealing member 32 between the pair of frame bodies 31 and 31. In this state, both frame bodies 31, 31 are screwed with screws 33. And the opening part 31a of each frame 31 is sealed with the two translucent plates 34 and 34 equivalent to the "translucent wall part" of this invention. Specifically, each of the translucent plates 34 and 34 is made of, for example, quartz glass and has a rectangular shape that is slightly larger than the opening 31a of the frame bodies 31 and 31 as a whole. In the present embodiment, for example, four rectangular plates are used. The glass plates 35 are arranged side by side. On each translucent plate 34, a pressing plate 36 having an opening 36a having the same shape as the opening 31a of each frame 31 is covered. Each of the translucent plates 34 is sandwiched between a peripheral portion of the opening 31a of each frame 31 and a peripheral portion of the opening 36a of each pressing plate 36. Are fixed by positioning with screws 37.

In addition, two conduction holes 32a are formed through both short side portions of the sealing member 32, and a connecting pipe 38 is provided so as to project from these through the connecting pipe 38 from a nitrogen supply means (not shown). Of nitrogen is supplied into the space M surrounded by the pair of translucent plates 34 and 34 and the sealing member 32.
As shown in FIGS. 1 and 3, the gas supply unit 30 includes a pair of translucent plates 34 arranged vertically in front of the irradiation direction of ultraviolet rays from the ultraviolet emitting unit 12 (downward in the drawing in the drawing). , 34 are arranged. The gas supply unit 30 is attached to the case 13 via a fixture 40 that protrudes downward from both longitudinal ends of the case 13.

Further, of the pair of translucent plates 34, 34, the translucent plate (hereinafter referred to as “work side translucent plate 34 a”) directed toward the workpiece W conveyance path 51 side is one of the pair of long side ends. A plurality of discharge holes 39 are formed in a line along the long side end at a position near the long side end.
In the present embodiment, a cooling means is provided so as to be along the pair of translucent plates 34. Specifically, the sealing member 32 is formed of a member having high heat conductivity, and as shown in FIG. 2, a U-shape in which a cooling liquid flows along the longitudinal direction on both long side portions thereof. The cooling pipe 42 is inserted so as to suppress the temperature rise of the gas supply unit 30 due to ultraviolet irradiation or nitrogen supply.

(3) Restriction wall In the present embodiment, as shown in FIG. 3, the periphery of the upper surface of the frame 31, 31 in the gas supply unit 30 is surrounded by the periphery of the opening 13 a of the ultraviolet emitting unit 12. Thus, the regulation wall 41 is formed upright.

3. Operational Effects of the Present Embodiment As shown in FIG. 3, the ultraviolet irradiation device 10 described above has the discharge hole 39 of the work-side translucent plate 34 a on the upstream side of the transfer path 51 above the transfer path 51 of the work W. Arranged in this way. In other words, the discharge hole 39 is positioned on the upstream side of the transport path 51 from the irradiation center X of the ultraviolet rays emitted from the ultraviolet lamp 11. When the ultraviolet irradiation device 10 is activated, the ultraviolet rays radiated from the lamp 11 are reflected downward by the pair of reflecting mirrors 17 and 17 and emitted from the opening 13 a of the case 13 toward the gas supply unit 30. The workpiece W on the transport path 51 is irradiated through the pair of translucent plates 34, 34 of the gas supply unit 30.

  Further, nitrogen (solid arrow G1 in FIG. 3) is supplied from the connection pipe 38 into the gas supply unit 30 and is discharged from the discharge hole 39 of the work-side light transmitting plate 34a. Thereby, it is possible to irradiate the processing part of the workpiece W (the upper surface of the workpiece W on which the UV resin is applied) with ultraviolet rays in a nitrogen atmosphere by blowing nitrogen onto the workpiece W conveyed through the conveyance path 51.

  Here, the discharge hole 39 is formed so as to penetrate the work-side light transmitting plate 34a through which the ultraviolet light from the ultraviolet light emitting portion 12 is transmitted, and the periphery of the work-side opening of the discharge hole 39 is the work-side light transmitting plate 34a (or The wall is formed by the work side translucent plate 34a and the frame 31). That is, a wall that prevents (suppresses) surrounding air from being entrained around the discharge hole 39 is provided. Therefore, in this configuration, unlike the conventional configuration in which the nitrogen supply is performed from a nozzle extending to the side of the housing, the surrounding air can be prevented (suppressed). In addition, the nitrogen stream released from the discharge hole 39 spreads laterally along the surface of the workpiece W, and the nitrogen stream can push out the atmosphere containing oxygen in the vicinity of the workpiece W. The upper UV resin 50 can be efficiently cured. Note that a greater effect can be obtained by shortening the distance between the gas supply unit 30 and the workpiece W as much as possible (for example, within 30 mm).

  Moreover, since the structure is such that nitrogen is blown directly onto the workpiece W from the discharge hole 39 formed in the portion through which the ultraviolet rays from the ultraviolet lamp 11 are transmitted (hereinafter referred to as “ultraviolet transmission portion”) in the workpiece-side translucent plate 34a. As compared with the above, it is possible to intensively reduce the oxygen concentration in a portion of the workpiece W irradiated with ultraviolet rays (hereinafter referred to as “ultraviolet irradiation portion”).

  Further, as described above, the regulation wall 41 is erected on the periphery of the upper surface of the frame 31 of the gas supply unit 30 so as to surround the ultraviolet emitting unit 12 (corresponding to the configuration of claim 2). ). Here, if the restriction wall 41 is not provided, the cooling fan 18 is driven, and the surrounding air including oxygen on the side of the gas supply unit 30 (two-dot broken line arrow G2 in FIG. 3) is drawn. There is a possibility that a part of the gas flows into the conveyance path 51 side of the workpiece W to increase the oxygen concentration. However, in this embodiment, when the cooling fan 18 is driven, the restriction wall 41 restricts the drawing of air around the side of the gas supply unit 30, and the surrounding air is drawn from above the restriction wall 41. A circulation path is formed through the lamp 11 and discharged from the exhaust port 19a. Therefore, it is possible to avoid the problem that the oxygen concentration on the conveyance path 51 side increases due to the drawing of the cooling fan 18.

  Furthermore, when the workpiece W is transported at a high speed, for example, at a speed of 1 to 100 m / min. Across the lower part of the ultraviolet irradiation device 10, as shown in FIGS. The workpiece W is dragged downstream. Therefore, in the present embodiment, the discharge hole 39 is provided at a position upstream of the irradiation center X in the ultraviolet light transmitting portion of the work side light transmitting plate 34a (corresponding to the structure of claim 3). Then, the upstream nitrogen having a large release amount is dragged downstream by the workpiece W, spreads in the entire lower area of the workpiece-side translucent plate 34a, and the workpiece W transported at a high speed with the discharge of a relatively small amount of inert gas. Thus, the oxygen concentration at the ultraviolet irradiation site can be efficiently reduced.

<Other embodiments>
The present invention is not limited to the embodiments described with reference to the above description and drawings. For example, the following embodiments are also included in the technical scope of the present invention, and further, within the scope not departing from the gist of the invention other than the following. Various modifications can be made.
(1) In the above embodiment, the ultraviolet curable resin is irradiated with ultraviolet rays and applied to an apparatus that supplies nitrogen as a gas. However, the present invention is not limited to nitrogen, and is a rare gas or carbon dioxide. Also good. In addition, for example, ashing or cleaning for decomposing organic substances by irradiating ultraviolet rays is performed, and the present invention can be applied to an apparatus for supplying ozone or oxygen.

(2) In the present embodiment, the discharge holes 39 are formed only on the upstream side of the glass plate 35, but the present invention is not limited to this, and a configuration formed on the central portion or the downstream side of the glass plate 35 may be used. Further, when the workpiece W is conveyed at high speed, a plurality of discharge holes whose diameter gradually decreases from the upstream side to the downstream side may be formed. Alternatively, the number of discharge holes on the upstream side may be larger than that on the downstream side.
Even in such a configuration, the workpiece W is irradiated with ultraviolet rays in a state where the oxygen concentration is efficiently reduced from the upstream side to the downstream side in the ultraviolet irradiation region from the ultraviolet ray emitting unit 12 in the conveyance path 51. Can do.

  (3) The discharge hole is formed in the ultraviolet light transmitting portion of the work side light transmitting wall portion (work side light transmitting plate 34a). For example, when the work side light transmitting wall portion is wide and there is a portion that is not irradiated with ultraviolet light. May be formed in a portion that is not irradiated with ultraviolet rays.

  (4) Even if the discharge hole has a configuration formed in a tubular portion protruding from the light transmitting wall portion, a prevention wall that prevents the surrounding air from being caught around the tubular portion (in this embodiment, the work side light transmitting light is prevented). The plate 34a and the frame body 31) connected to the plate 34a need only be provided, and even with this configuration, the effects of the present invention can be obtained.

The partial sectional view of the whole ultraviolet irradiation device concerning one embodiment of the present invention Bottom view as seen from workpiece transfer path Sectional drawing in the XX fracture surface of FIG. Cross-sectional view of an ultraviolet irradiation device showing the flow of nitrogen sprayed onto a workpiece being conveyed at high speed Cross-sectional view of a conventional ultraviolet irradiation device

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Ultraviolet irradiation apparatus 11 ... Ultraviolet lamp 18 ... Cooling fan (intake means)
DESCRIPTION OF SYMBOLS 30 ... Gas supply part 34 ... Translucent plate 34a ... Work side side translucent plate 39 ... Release hole 41 ... Restriction wall 50 ... Ultraviolet curable resin 51 ... Conveyance path G1 ... Nitrogen (gas)
G2 ... Ambient air L ... Ultraviolet light W ... Workpiece X ... Irradiation center

Claims (3)

In an ultraviolet irradiation device that irradiates a workpiece with ultraviolet rays from an ultraviolet lamp,
Between the ultraviolet lamp and the workpiece, there is a pair of light transmitting wall portions arranged side by side with a space therebetween, and gas is supplied to a space sandwiched between the pair of light transmitting wall portions. A gas supply unit is provided, configured to irradiate the workpiece with ultraviolet rays from the ultraviolet lamp through the pair of translucent walls;
An ultraviolet irradiation apparatus, wherein a light transmitting wall portion disposed on the workpiece side is provided with a discharge hole for discharging the gas to the workpiece side. It is configured to cool the ultraviolet lamp by a cooling air intake means,
2. The ultraviolet ray according to claim 1, wherein a restriction wall for restricting air around the gas supply part from being drawn in by the intake means is provided on the side of the gas supply part. Irradiation device. The workpiece is transported across the irradiation path of ultraviolet rays from the ultraviolet lamp, and the discharge hole is formed only on the upstream side of the conveyance path of the workpiece from the irradiation center of ultraviolet rays from the ultraviolet lamp, or 3. The ultraviolet irradiation device according to claim 1, wherein the ultraviolet irradiation device is formed so as to release a larger amount of gas from the discharge hole on the upstream side than on the downstream side.

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