JP2008281934A - Ultraviolet radiation device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ultraviolet radiation device that elongates lifetime of an ultraviolet lamp and prevents the freezing of mercury to thereby control the decrease of illuminance to the utmost. <P>SOLUTION: The ultraviolet radiation device includes: an ultraviolet lamp lighting device 12 for switching and lighting an ultraviolet lamp UVL at a plurality of light levels; a shutter means 22 for switching radiation and non-radiation by passing or shutting off light from the ultraviolet lamp; a cooling means 21d for cooling the ultraviolet lamp; a control means OC for controlling a power level H of the ultraviolet lamp during radiation is larger than a power level L of the ultraviolet lamp during non-radiation, while being linked with the operation of the ultraviolet lamp lighting device and the shutter means; and a cooling power regulating means 21 for strongly or weakly regulating the cooling power of the cooling means depending on a ratio of a radiation time and a non-radiation time. Thus, the lamp is controlled such that the lamp temperature is maintained substantially constant by increasing or decreasing the cooling power depending on the magnitude of electric power applied to the lamp. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an ultraviolet irradiation device.

  In recent years, an ultraviolet irradiation device using an ultraviolet lamp as a light source has been widely used for an ultraviolet spot irradiation device, an exposure device, an adhesive device using ultraviolet rays, and the like.

  The UV irradiation device increases the light output during UV irradiation by increasing the input power to the UV lamp, which is the light source, to a high level only during UV irradiation, and to a low level when not irradiating, and also consumes power during non-irradiation. Can be reduced (Japanese Patent Laid-Open Nos. 60-59733 and 61-20324).

  In the case of such an ultraviolet irradiation device, the average power input to the ultraviolet lamp as a light source varies depending on the relationship between the ultraviolet irradiation time and the non-irradiation time. For example, when irradiation power is Pa, non-irradiation power is Pb, irradiation time is Ta, non-irradiation time is Tb, and irradiation of Ta time and non-irradiation of Tb time are cyclically repeated, an ultraviolet lamp The average power input to is expressed by the following equation.

Average power = Pb + (Pa−Pb) × (Ta / (Ta + Tb)) (1)
Therefore, when the values of the electric power Pa and Pb are fixed, the input power to the ultraviolet lamp varies depending on the ratio between the ultraviolet irradiation time and the non-irradiation time.

  On the other hand, in the above ultraviolet irradiation apparatus, a method of arbitrarily switching between irradiation / non-irradiation based on an external signal is widely adopted. However, in the conventional ultraviolet irradiation apparatus, it is known that the average input power is changed depending on the ratio of the ultraviolet irradiation time and the non-irradiation time. However, the cooling power of the cooling means for cooling the ultraviolet lamp depends on the average input power. No technology is known for making it variable.

When the average input power is changed according to the ratio of the ultraviolet irradiation time and the non-irradiation time, the cooling power of the cooling means for cooling the ultraviolet lamp is made constant without being variably adjusted according to the average input power. When the ratio is relatively large, there is a problem that the lamp temperature becomes high and the lamp life is shortened. On the other hand, when the ratio of irradiation time is small, the lamp temperature becomes low and is enclosed in the ultraviolet lamp together with other gases. There is a problem that the illuminance decreases due to solidification of mercury.
JP 60-59733 A JP 61-20324 A

  The present invention has been made in view of the above-mentioned problems of the prior art, and by increasing or decreasing the cooling power according to the lamp input power, the lamp temperature is kept almost constant, the lamp life is prolonged, and mercury coagulation is prevented. It aims at providing the ultraviolet irradiation device which can suppress the fall of illumination intensity as much as possible.

  The present invention provides an ultraviolet lamp lighting device that switches on and turns on an ultraviolet lamp at a plurality of light levels, shutter means for switching between irradiation and non-irradiation by passing / shielding light from the ultraviolet lamp, and cooling the ultraviolet lamp. In conjunction with the operation of the cooling means, the ultraviolet lamp lighting device, and the shutter means, the power level H of the ultraviolet lamp at the time of irradiation and the power level L of the ultraviolet lamp at the time of non-irradiation are controlled to be H> L. It is characterized by an ultraviolet irradiation device comprising a control means and a cooling power adjusting means for adjusting the cooling power of the cooling means in accordance with the ratio between the irradiation time and the non-irradiation time.

  In the ultraviolet irradiation apparatus, the control means controls the power level based on an irradiation / non-irradiation switching signal given from the outside, and the cooling power adjustment means uses the irradiation / non-irradiation switching signal given from the outside. Based on the detected irradiation time and non-irradiation time, the cooling power of the cooling means can be adjusted in accordance with the ratio of the detected irradiation time and non-irradiation time.

  In the ultraviolet irradiation apparatus, the control unit controls the power level based on an irradiation / non-irradiation switching signal given from the outside, and the cooling power adjustment unit performs irradiation based on an opening / closing operation of the shutter unit. Time and non-irradiation time can be detected, and the cooling power of the cooling means can be adjusted in accordance with the ratio between the detected irradiation time and non-irradiation time.

  According to the present invention, an ultraviolet irradiation device capable of keeping the lamp temperature substantially constant by increasing or decreasing the cooling power according to the magnitude of the power supplied to the lamp, extending the lamp life, preventing mercury solidification, and suppressing the decrease in illuminance as much as possible. Can be realized.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  (First Embodiment) FIG. 1 and FIG. 2 show an ultraviolet irradiation device, which includes an ultraviolet irradiation device main body 11 and an ultraviolet lamp lighting device 12. The ultraviolet irradiation device main body 11 includes an optical system 11a, a light control mechanism 11b, an optical shutter 11c, a cooling mechanism 11d, an irradiation port 11e, and a casing 11f. The ultraviolet lamp UVL has a tube shaft suspended vertically at an upper position inside the casing 11f.

  The optical system 11a is an optical means for condensing the ultraviolet rays radiated from the ultraviolet lamp UVL such as a short arc type mercury lamp downward and leading out from the irradiation port 11e. The elliptical reflecting mirror 11a1 and the first mirror 11a2 The light guide 11a3 and the second mirror 11a4. The elliptical reflecting mirror 11a1 reflects the ultraviolet rays radiated from the ultraviolet lamp UVL on its reflecting surface and collects the light downward. The first mirror 11a2 reflects the collected ultraviolet rays, bends 90 °, and advances in the horizontal direction. The light guide 11a3 guides the ultraviolet light to the outside of the casing 11f after the ultraviolet light traveling in the horizontal direction passes through the light control mechanism 11b and the optical shutter 11c. The second mirror 11a4 reflects the ultraviolet light derived from the other end of the light guide 11a3 and bends it 90 ° downward. The ultraviolet rays bent downward are led out from the irradiation port 11e and irradiate a workpiece (not shown).

  The light control mechanism 11b adjusts the ultraviolet illuminance at the time of irradiating the workpiece, which is derived from the irradiation port 11e, as desired. The light control mechanism 11b is composed of a rotating disk in which a large number of openings having different opening areas are formed concentrically, and performs light control by rotating the rotating disk and selecting an opening area of the opening as desired.

  The optical shutter 11c passes (opens) the ultraviolet light that has passed through the light control mechanism 11b, and makes it incident on the light guide 11a3, or blocks (closes) it so that it does not enter the light guide 11a3. It is opened when the workpiece is irradiated with ultraviolet rays, and is closed when the workpiece is not irradiated with ultraviolet rays.

  The cooling mechanism 11d exhausts and cools the inside of the casing 11f.

  The casing 11f accommodates the above means and the ultraviolet lamp lighting device 12 in a predetermined position inside.

  The ultraviolet lamp lighting device 12 will be described with reference to FIGS. The ultraviolet lamp lighting device 12 includes an ultraviolet lamp UVL and a lighting circuit OC. The lighting circuit OC shown in FIG. 3 is a circuit for lighting the ultraviolet lamp UVL while intermittently changing the lamp power to be applied. In the intermittent operation, as shown in FIG. 4, a first period T1 for supplying a relatively large power H under constant current control and a second period T2 for supplying a relatively small power L are alternately repeated. Is done. In the second period T2, constant current control or constant power control may be used. Further, the lighting circuit OC performs constant current control on the lamp power input during at least the first period T1. For this purpose, a DC constant current control circuit CCR is used for the lighting circuit OC, and a constant current obtained from between its output terminals is supplied to the ultraviolet lamp UVL. When performing constant power control in the second period T2, in addition to the DC constant current control circuit CCR, a constant power control circuit is arranged in parallel or in series, and these control circuits are switched for each period. It connects so that it may connect with ultraviolet lamp UVL.

  A rectifier circuit RC is provided at the input end of the DC constant current control circuit CCR to supply DC power, and an AC voltage obtained from the AC power supply AC is rectified using this circuit. Further, the lighting circuit OC uses the control circuit CC to change the lamp current output from the DC constant current control circuit CCR to a value necessary for each period in order to intermittently change the lamp power input to the ultraviolet lamp UVL. I want to be in control. In addition, the period of the intermittent fluctuation is appropriately set depending on the target of ultraviolet irradiation. For example, the first and second periods T1 and T2 are each set to about 10 seconds.

  Next, the operation of the ultraviolet lamp lighting device 12 will be described. As shown in the waveform diagram of FIG. 5, the ultraviolet lamp UVL continues to be lit by the lamp power that fluctuates intermittently. At the relatively high power H input in the first period T1, the ultraviolet lamp UVL increases the ultraviolet output. Therefore, when the ultraviolet rays generated in the first period T1 are used for the purpose of exposure or the like, it is possible to perform ultraviolet irradiation with high efficiency in a short time. In the relative low power L input in the second period T2, the ultraviolet lamp UVL maintains the lighting state although the ultraviolet output decreases. Therefore, the second period T2 can be set as a standby period until the next ultraviolet irradiation. By doing so, power consumption during standby can be minimized.

  The temperature control in the ultraviolet irradiation apparatus having such a configuration will be described using the temperature control circuit 20 of FIG. The temperature control circuit 20 includes a cooling power adjustment function unit 21, an ultraviolet lamp lighting device 12, and a shutter mechanism unit 22.

  The ultraviolet lamp lighting device 12 is operated by the above-described lighting device OC for switching the ultraviolet lamp UVL between two irradiation levels in the irradiation mode and the non-irradiation mode, and the power variable signal of the lighting device OC. 4 is provided with an electronic ballast 12b that supplies the UVL with the H power and the L power in FIG.

  The cooling power adjustment function unit 21 detects an opening / closing time detection unit 21a that detects a shutter opening / closing time based on a shutter opening / closing signal given from the outside, and the ratio corresponding to the shutter opening / closing time detected by the opening / closing time detection unit 21a. (Duty) is calculated, and the calculation unit 21b that outputs an air volume adjustment signal based on the duty: air volume graph shown in FIG. 6, the air volume adjustment mechanism part 21c that adjusts the fan rotating power level, and the air volume adjustment mechanism part 21c. The fan 21d is provided as a cooling means for adjusting the air volume by changing the number of rotations according to the air flow instruction value. The fan 21d is accommodated in a cooling mechanism 11d in the mechanism shown in FIGS.

  The shutter mechanism unit 22 includes a shutter 11c that switches between irradiation / non-irradiation by passing / blocking light from the ultraviolet lamp UVL, a shutter opening / closing unit 22a that opens and closes the shutter 11c by an external shutter opening / closing signal, and a shutter 11c includes an open sensor 22b and a close sensor 22c for detecting the open / closed state of 11c.

  The temperature control circuit 20 configured as described above performs a temperature control operation as follows. In response to an external shutter opening / closing signal, the ultraviolet lamp lighting device 12 switches to the irradiation mode when the shutter is opened and the non-irradiation mode when the shutter is closed, and switches the H and L2 power levels in FIG. To supply. The ratio T1 / (T1 + T2) between the irradiation time T1 and the non-irradiation time T2 is the duty. On the other hand, the shutter mechanism unit 22 opens and closes the shutter 11c in response to an external shutter opening / closing signal.

  Then, the cooling power adjustment function unit 21 is linked to the ultraviolet lamp lighting device 12 and the shutter mechanism unit 22, and is a time ratio between the power level H of the ultraviolet lamp UVL during irradiation and the power level L of the ultraviolet lamp UVL during non-irradiation ( The air volume of the fan 21d is adjusted based on the graph of FIG. In the case of the characteristics shown in the graph of FIG. 6, linear control is performed in which the air volume is reduced when the duty is small and the air volume is increased when the duty is large.

  As a result, as shown in FIG. 7, when the fan is rotated at a constant speed without performing the conventional temperature control, the maximum lamp temperature Tp1 is increased by the increase of the duty. In this case, the maximum lamp temperature Tp2 can be maintained substantially constant by adjusting the fan air volume in accordance with the duty.

  (Second Embodiment) An ultraviolet irradiation apparatus according to a second embodiment of the present invention will be described with reference to FIGS. 1 to 4 and FIGS. The mechanical configuration of the ultraviolet irradiation device of the second embodiment is as shown in FIGS. 1 and 2 as in the first embodiment, and the circuit configuration and power control operation of the ultraviolet lamp lighting circuit 12 are as follows. FIG. 3 and FIG. 4 are common to the first embodiment. Therefore, elements common to the first embodiment will be described using common reference numerals.

  The feature of the present embodiment resides in the temperature control circuit 20A shown in FIG. In the case of the present embodiment, unlike the first embodiment, the cooling power adjustment function unit 21A adjusts the strength of the cooling power based on the irradiation / non-irradiation switching signal inside the apparatus. That is, according to the present embodiment, in the cooling power adjustment function unit 20A, the open / close time detection unit 21a detects the shutter open time and the close based on the shutter open signal and the shutter close signal detected by the shutter open sensor 22b and the close sensor 22c. The time is detected, the calculation unit 21b calculates the duty corresponding to the shutter opening / closing time detected by the opening / closing time detection unit 21a, and outputs the air volume adjustment signal based on the duty: air volume graph shown in FIG. The air volume adjusting mechanism 21c adjusts the fan rotational power level, and the fan 21d adjusts the air volume by changing the rotation speed in accordance with the air volume instruction value from the air volume adjusting mechanism 21c.

  Also in this embodiment, as shown in FIG. 7, as in the first embodiment, the maximum temperature of the ultraviolet lamp UVL is maintained substantially constant as compared with the conventional ultraviolet irradiation device that does not adjust the air volume. There are advantages that can be made.

  In the above-described embodiments, the short arc mercury lamp is exemplified as the ultraviolet lamp UVL. However, the ultraviolet lamp to which the present invention can be applied is not limited to this, but other kinds of ultraviolet lamps that require cooling. Is also applicable.

  In order to adjust the cooling power, it is possible to control the fan input voltage, input current, or power frequency, or to provide a mechanism that mechanically closes the opening so that the opening area is controlled to be wide or narrow. it can.

The front view of the ultraviolet irradiation device of the 1st, 2nd embodiment of this invention. The side view of the ultraviolet irradiation device of the 1st, 2nd embodiment of this invention. The circuit block diagram of the ultraviolet lamp lighting device in the ultraviolet irradiation device of the 1st, 2nd embodiment of this invention. The wave form diagram of the lamp electric power thrown into the ultraviolet lamp in the ultraviolet irradiation device of the 1st, 2nd embodiment of this invention. The block diagram of the temperature control circuit in the ultraviolet irradiation device of the 1st Embodiment of this invention. The graph which shows the response | compatibility with the duty of the lamp input power by the temperature control circuit in the ultraviolet irradiation device of the 1st, 2nd embodiment of this invention, and a fan airflow. The graph which shows the response | compatibility with the duty of the lamp input power by the temperature control circuit in the ultraviolet irradiation device of the 1st, 2nd embodiment of this invention, and the maximum temperature of an ultraviolet lamp compared with the case of a prior art example. The block diagram of the temperature control circuit in the ultraviolet irradiation device of the 2nd Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 ... Ultraviolet irradiation device 12 ... Ultraviolet lamp lighting device UVL ... Ultraviolet lamp OC ... Lighting circuit 11c ... Shutter 11d ... Cooling mechanism 20, 20A ... Temperature control circuit 21, 21A ... Cooling power adjustment function part 21a ... Opening / closing time detection part 21b ... Arithmetic unit 21c ... Air volume adjusting mechanism unit 21d ... Fan 22 ... Shutter mechanism 22a ... Shutter opening / closing unit 22b ... Open sensor 22c ... Close sensor

Claims (3)

An ultraviolet lamp lighting device that switches on and turns on an ultraviolet lamp at a plurality of light levels;
Shutter means for switching between irradiation / non-irradiation by passing / shielding light from the ultraviolet lamp;
Cooling means for cooling the ultraviolet lamp;
Control means for controlling the power level H of the ultraviolet lamp at the time of irradiation and the power level L of the ultraviolet lamp at the time of non-irradiation in conjunction with the operation of the ultraviolet lamp lighting device and the shutter means;
An ultraviolet irradiation apparatus comprising: a cooling power adjusting unit that adjusts the cooling power of the cooling unit according to a ratio between the irradiation time and the non-irradiation time. The control means controls the power level based on an irradiation / non-irradiation switching signal given from the outside,
The cooling power adjusting means detects an irradiation time and a non-irradiation time based on an irradiation / non-irradiation switching signal given from the outside, and cools the cooling means according to a ratio of the detected irradiation time and non-irradiation time. The ultraviolet irradiation device according to claim 1, wherein the strength is adjusted. The control means controls the power level based on an irradiation / non-irradiation switching signal given from the outside,
The cooling power adjusting means detects the irradiation time and the non-irradiation time based on the opening / closing operation of the shutter means, and adjusts the cooling power of the cooling means in accordance with the ratio between the detected irradiation time and the non-irradiation time. The ultraviolet irradiation device according to claim 1.

Images