JP2021145976A - Ultraviolet lamp - Google Patents

Abstract

To provide an ultraviolet lamp capable of detecting sterilization performance within an apparatus with a simple device.SOLUTION: An ultraviolet lamp comprises: an ultraviolet light source 51, which has an ultraviolet reflective material on at least a part, is provided on at least one end or the other end of the treatment flow path L through which a target object passes and the treatment flow path L, and applies ultraviolet light toward the target object that passes the treatment flow path L; a first detector 6, which is arranged at an end on a side on which the ultraviolet light source 51 of the treatment flow path L and detects a light amount of ultraviolet light reflected by the ultraviolet ray reflective material of the treatment flow path L; and a shielding member 8 arranged on a straight line connecting the light emitting surface of the ultraviolet light source 51 and the light receiving surface of the first detector 6. Since the first detector 6 detects the change of the ultraviolet light reflectance of the ultraviolet light in the flow path L and the ultraviolet light which is influenced by the change of the ultraviolet transmittance of the irradiation target, by estimating the sterilization performance based on the light amount of the detected ultraviolet light, the sterilization performance of the ultraviolet lamp can be detected with higher accuracy.SELECTED DRAWING: Figure 1

Description

The present invention relates to an ultraviolet irradiation device.

Since ultraviolet light has a sterilizing ability, an ultraviolet irradiation device that continuously sterilizes a fluid by irradiating a fluid such as water with ultraviolet light has been proposed. In such an ultraviolet irradiation device, a device has been proposed in which the amount of ultraviolet light is detected and the driving amount of the ultraviolet LED is adjusted so that the amount of ultraviolet irradiation of the ultraviolet LED becomes a desired value based on the detected amount of light. ing. For example, a method of detecting the total amount of ultraviolet rays by measuring the amount of light transmitted through a reflective portion of the irradiated ultraviolet rays (see, for example, Patent Document 1), the illuminance of the ultraviolet rays, and the object to be sterilized. A method of measuring the transmittance and flow rate of a liquid and controlling the illuminance of ultraviolet rays and the flow rate of the liquid to be sterilized according to these measurement results (see, for example, Patent Document 2) has been proposed.

Japanese Patent No. 6549456 Japanese Patent No. 3920504 Japanese Unexamined Patent Publication No. 2019-201861 International Publication No. 2019/09343 Japanese Unexamined Patent Publication No. 2019-188128

However, in the method of measuring the amount of light transmitted through the reflecting portion as in Patent Document 1, the transmittance of the reflecting portion is low, and as a method of measuring the amount of light, the detection sensitivity is low and the S / N ratio is lowered. .. As a method of increasing the detection sensitivity, it is conceivable to increase the amount of transmitted light of the reflector, but for that purpose, it is necessary to reduce the thickness of the reflector. When the thickness of the reflective material is reduced, the reflectance of the reflective material is lowered, the irradiation efficiency of running water is lowered, and the sterilization performance is lowered.
Further, in an ultraviolet irradiation device for sterilizing a fluid, a method of controlling a light source based on the illuminance of ultraviolet rays, the transmittance and the flow rate of the liquid to be sterilized, which affect the sterilization performance of the device, is described in Patent Document 2. As described above, it is necessary to provide detectors for measuring these illuminance, transmittance, and flow rate, which complicates the device.

Therefore, the present invention has been made by paying attention to the above-mentioned conventional unsolved problems, and an object of the present invention is to provide an ultraviolet irradiation device capable of detecting the sterilization performance in the device by a simple device configuration. It is said.

The ultraviolet irradiation device according to an embodiment of the present invention has an ultraviolet reflecting material at least in a part thereof, and a processing flow path through which an object passes from one end side to the other end side, and the one end of the processing flow path or the above. An ultraviolet light source provided on at least one of the other ends and irradiating ultraviolet light toward the object passing through the processing flow path, and an ultraviolet light source on the processing flow path on the side where the ultraviolet light source is provided. On a straight line connecting the first detector that detects the amount of ultraviolet light reflected by the ultraviolet reflecting material in the processing flow path, the light emitting surface of the ultraviolet light source, and the light receiving surface of the first detector. It is characterized by having a first UV shield to be placed.

According to one aspect of the present invention, the sterilization performance in the apparatus can be detected with a simple configuration.

It is a vertical cross-sectional view which shows an example of the schematic structure of the ultraviolet irradiation apparatus which concerns on 1st Embodiment. It is a characteristic diagram which shows an example of correspondence between the output of the 1st detector and the sterilization performance when the transmittance of ultraviolet rays of an irradiation object is different. It is an optical simulation result which analyzed the illuminance distribution in the processing flow path in the ultraviolet irradiation apparatus which concerns on 1st Embodiment under the condition that the internal transmittance is different. It is a characteristic diagram which shows an example of correspondence between the output of the 1st detector and the sterilization performance when the transmittance of ultraviolet rays of an irradiation object is different. It is a vertical cross-sectional view which shows the comparative example of the ultraviolet irradiation apparatus. It is a vertical cross-sectional view which shows an example of the schematic structure of the ultraviolet irradiation apparatus which concerns on 2nd Embodiment. It is a vertical sectional view which shows an example of the schematic structure of the ultraviolet irradiation apparatus which concerns on 3rd Embodiment. It is a vertical sectional view which shows an example of the structure of the ultraviolet irradiation apparatus which concerns on 4th Embodiment. It is a vertical cross-sectional view which shows an example of the structure of the irradiation part of the ultraviolet irradiation apparatus which concerns on 4th Embodiment. It is a schematic block diagram which shows an example of the management circuit of the ultraviolet irradiation apparatus which concerns on 4th Embodiment. It is a figure which shows an example of the operation waveform of the target value setting state of the ultraviolet irradiation apparatus which concerns on 4th Embodiment. It is a figure which shows an example of the operation waveform of the target value setting state of the ultraviolet irradiation apparatus which concerns on 4th Embodiment. It is a figure which shows an example of the operation waveform at the time of transitioning from the target value setting state to the operation state of the ultraviolet irradiation apparatus which concerns on 4th Embodiment.

Next, an embodiment of the present invention will be described with reference to the drawings. In the description of the drawings below, the same or similar parts are designated by the same or similar reference numerals. However, the drawings are schematic, and the relationship between the thickness and the plane dimensions, the ratio of the thickness of each layer, etc. are different from the actual ones. In addition, there are parts in which the relations and ratios of the dimensions of the drawings are different from each other.
In addition, the embodiments shown below exemplify devices and methods for embodying the technical idea of the present invention, and the technical idea of the present invention describes the arrangement of components and the like as follows. Not specific. The technical idea of the present invention may be modified in various ways within the technical scope specified by the claims stated in the claims.

<First Embodiment>
FIG. 1 is a vertical cross-sectional view showing an example of a schematic configuration of an ultraviolet irradiation device according to a first embodiment of the present invention.
The ultraviolet irradiation device 1-1 is a fluid sterilizer that sterilizes a fluid as an irradiation target.
As shown in FIG. 1, the ultraviolet irradiation device 1-1 includes an inflow unit 2, an outflow unit 3, a housing 4, an irradiation unit 5, a first detector 6, a control device 7, and a shielding member ( The first ultraviolet shield) 8 and the like are provided.

The housing 4 is provided with an inflow portion 2 and an outflow portion 3 at intervals on the side surface thereof. The housing 4 is made of an ultraviolet reflective material. The ultraviolet reflective material referred to here is a material having a total reflectance of 60 [%] / 1 [mm] or more and 99 [%] / 1 [mm] or less in the ultraviolet region. Examples of the ultraviolet reflective material include polytetrafluoroethylene PTFE, silicon resin, quartz glass containing bubbles of 0.05 [μm] or more and 10 [μm] or less inside, and 0.05 [μm] or more and 10 inside. Partially crystallized quartz glass containing crystal grains of [μm] or less, alumina sintered body of 0.05 [μm] or more and 10 [μm] or less, and 0.05 [μm] or more and 10 [μm] or less. Examples thereof include materials containing at least one of crystalline and granular mulite sintered bodies and the like. The housing 4 may be provided with an ultraviolet reflective material on at least a part of the inner peripheral surface which is the wall surface of the processing flow path L, and may not necessarily be formed of the ultraviolet reflective material. The inside of the housing 4 becomes the processing flow path L, and the irradiation target is introduced into the inside of the housing 4 from the inflow portion 2 and discharged from the outflow portion 3 through the processing flow path L. The object to be irradiated is not limited to a fluid but may be a gas or the like, but from the viewpoint of heat dissipation, a fluid is preferable, and a fluid containing water such as water, an aqueous solution, and an aqueous dispersion is particularly preferable.

The irradiation unit 5 is provided on the open end side of the housing 4. The irradiation unit 5 includes an ultraviolet light source 51 such as a light emitting element and a substrate 52 on which the ultraviolet light source 51 is mounted. For example, processing is performed by arranging the irradiation surface of the ultraviolet light source 51 toward the inside of the housing 4 by sandwiching a window (not shown) formed of an ultraviolet transmissive member such as quartz glass at the open end of the housing 4. The irradiation target passing through the flow path L is irradiated with ultraviolet light.

The first detector 6 detects the amount of ultraviolet light, and outputs a detection signal including a voltage signal or a current signal according to the amount of ultraviolet light to the control device 7. The first detector 6 is provided, for example, on the substrate 52.
The control device 7 drives and controls the ultraviolet light source 51 and receives the detection signal of the first detector 6. Further, the control device 7 drives and controls the ultraviolet light source 51 so that the irradiation target is irradiated with ultraviolet light having a preset amount of light. It is also possible to drive the ultraviolet light source 51 with a constant current and issue an alarm when the value falls below a preset “detection signal threshold”.

The shielding member 8 is arranged on a straight line connecting the light emitting surface of the ultraviolet light source 51 and the light receiving surface of the first detector 6, and shields the ultraviolet light directly incident on the first detector 6 from the ultraviolet light source 51. The shielding member 8 may be a member having a diffusion transmittance of 0.5% or less, and for example, a metal such as aluminum or stainless steel, or an LED substrate material such as FR4 can be applied. The shielding member 8 has, for example, a plate shape, is provided on the substrate 52, and is arranged so that the tip of the shielding member 8 is about the same as the tip of the ultraviolet light source 51. This prevents the ultraviolet light emitted by the ultraviolet light source 51 from being directly incident on the first detector 6.

The ultraviolet irradiation device 1-1 is provided with ultraviolet light sources 51 at both ends of the housing 4, and irradiates the irradiation target object passing through the processing flow path L with ultraviolet light from both ends of the processing flow path L. It may be. Further, as shown in FIG. 1, the ultraviolet irradiation device 1-1 causes a fluid to be sterilized as an irradiation target to flow along the longitudinal direction of the treatment flow path L, and from one end of the treatment flow path L in the longitudinal direction. Any device may be used as long as it irradiates the object to be irradiated with ultraviolet light. Specifically, for example, as shown in Patent Document 3, an ultraviolet treatment device may be used in which the irradiation target is allowed to flow along the axial direction of the cylinder, and as shown in FIG. 8 described later. Ultraviolet rays that have an outer cylinder and an inner cylinder, and introduce an irradiation object into the gap between the outer cylinder and the inner cylinder, and introduce the irradiation object from one end side of the inner cylinder into the processing flow path in the inner cylinder. It may be a processing device.

FIG. 2 shows the output [mV] of the first detector 6 and the bactericidal MS2 as index bacteria in the ultraviolet irradiation device 1-1 shown in FIG. 1 when the transmittance of the ultraviolet light of the irradiation target is different. It shows the correspondence with the sterilization performance LRV when the existing bacterial solution is flowed into the apparatus at a flow rate of 3 L / min. The horizontal axis is the output of the first detector 6 (detector output), and the vertical axis is the sterilization performance LRV. Further, in FIG. 2, the symbol “●” indicates the correspondence when the transmittance is 100%, the symbol “○” indicates the transmittance when the transmittance is 95.8%, and the symbol “×” indicates the correspondence when the transmittance is 84.7%. .. As shown in FIG. 2, a correlation can be found between the output of the first detector 6 and the sterilization performance LRV regardless of the transmittance, and the correlation function can be expressed by y = 0.0044x. .. Further, the coefficient of determination R ² (R is a correlation coefficient) is R ² = 0.9576, and a positive correlation can be found.

FIG. 3 shows a case where PTFE having a diffuse reflectance of 85% is used for the processing flow path L and the inside of the processing flow path L is filled with a fluid having a transmittance of 99%, 95%, or 85%. It shows the ultraviolet illuminance distribution. When the flow velocity distribution in the treatment flow path L is constant, the sterilization performance of the ultraviolet irradiation device 1-1 correlates with the average illuminance in the treatment flow path L, but as shown in FIG. 3, the inside of the treatment flow path L If the transmittance of the fluid is low, the average illuminance also decreases, and as a result, the sterilization performance of the ultraviolet irradiation device 1-1 also decreases. Since the first detector 6 detects the illuminance in the processing flow path L, the amount of light received by the first detector 6 correlates with the average illuminance in the processing flow path L, and as shown in FIG. (1) The output of the detector 6 correlates with the sterilization performance.

As shown in FIG. 5, FIG. 4 shows the output [mV] of the first detector 6 and the bacterial solution using the bacteriophage MS2 as index bacteria when the shielding member 8 is not provided in the ultraviolet irradiation device 1-1. It shows the correspondence with the sterilization performance LRV when the blood is flowed into the apparatus at a flow rate of 3 L / min. The horizontal axis is the output of the first detector 6 (detector output), and the vertical axis is the sterilization performance LRV. Further, in FIG. 4, the symbol “●” indicates the correspondence when the transmittance is 100%, the symbol “○” indicates the transmittance when the transmittance is 95.8%, and the symbol “×” indicates the correspondence when the transmittance is 84.7%. .. From FIG. 4, a positive correlation can be found between the output of the first detector 6 and the sterilization performance LRV when the transmittances of the irradiated objects are the same, but when the transmittances are different, It can be seen that the correlation shown in FIG. 2 cannot be obtained.

As described above, according to the ultraviolet irradiation device 1-1 according to the first embodiment of the present invention, the process is performed in order to adjust the light emission amount of the ultraviolet light source 51 by using the detection signal detected by the first detector 6. The amount of light emitted from the ultraviolet light source 51 can be adjusted based on the amount of transmitted light in consideration of changes in the absorption rate and the reflectance of ultraviolet light in the flow path L. As a result, the desired sterilization performance can be obtained even if the absorption characteristics and reflection characteristics of ultraviolet light in the processing flow path L change while the ultraviolet irradiation device 1-1 is in operation.

Here, when applied to a fluid sterilizer that irradiates running water with ultraviolet light, the ultraviolet light transmittance of running water and the ultraviolet light reflectance of the housing material forming the processing flow path L may cause deterioration or dirt of the device. It changes depending on the quality of flowing water. According to the ultraviolet irradiation device 1-1 according to the first embodiment, the sterilization performance can be maintained by following such changes in the absorption rate and the reflectance that change from moment to moment. Further, even when the light source is driven by a constant current without controlling the light amount according to the detected amount, not only the fluctuation of the ultraviolet transmittance of the running water and the reflectance of the reflector but also the decrease in the light amount due to the deterioration of the light source is detected. It is possible, and when the detected amount falls below a certain threshold, an alarm prompting the replacement of the light source can be issued.

<Second Embodiment>
FIG. 6 is a vertical cross-sectional view showing an example of a schematic configuration of an ultraviolet irradiation device according to a second embodiment of the present invention. The ultraviolet irradiation device 1-2 according to the second embodiment has a different arrangement position of the first detector 6 in the ultraviolet irradiation device 1-1 according to the first embodiment. The same parts as those of the ultraviolet irradiation device 1-1 in the first embodiment are designated by the same reference numerals, and detailed description thereof will be omitted.
In the ultraviolet irradiation device 1-2 according to the second embodiment, instead of providing the shielding member 8 in the ultraviolet irradiation device 1-1, the first detector 6 is used as the ultraviolet light source 51 on the substrate 53 on which the ultraviolet light source 51 is mounted. It is provided on the opposite side of the surface.

Specifically, as shown in FIG. 6, the substrate 53 is provided with a through hole 53a. The through hole 53a is formed at a position where the ultraviolet light reflected by the reflective material of the processing flow path L can be received.
The ultraviolet light source 51 is provided so that the irradiation surface faces the through hole 53a. That is, the reflected light from the processing flow path L is incident on the through hole 53a, and the ultraviolet light that has passed through the through hole 53a is incident on the first detector 6, so that the first detector 6 is the processing flow path. The amount of ultraviolet light reflected by L is measured only.

With such a configuration, it is possible to obtain the same action and effect as the ultraviolet irradiation device 1-1 in the first embodiment, and since it is not necessary to provide the shielding member 8, it is realized with a simpler structure. be able to. In the case of the ultraviolet irradiation device 1-2, since a part of the substrate 53 exists on the straight line connecting the light emitting surface of the ultraviolet light source 51 and the light receiving surface of the first detector 6, the substrate 53 is transmitted from the ultraviolet light source 51. It serves as a shielding member that shields ultraviolet light directly incident on the first detector 6.

<Third Embodiment>
FIG. 7 is a vertical cross-sectional view showing an example of a schematic configuration of an ultraviolet irradiation device according to a third embodiment of the present invention. The ultraviolet irradiation device 1-3 according to the third embodiment is the second detection in the ultraviolet irradiation device 1-2 according to the second embodiment, which further measures the amount of ultraviolet light (direct light amount) directly incident from the light source. A vessel 9 is provided. The same parts as those of the ultraviolet irradiation device 1-2 in the second embodiment are designated by the same reference numerals, and detailed description thereof will be omitted.

In the ultraviolet irradiation device 1-3 according to the third embodiment, the substrate 53 is provided with a through hole 53a for providing the first detector 6, and further, a through hole 53b for providing the second detector 9. Is provided.
The second detector 9 is a light amount detector for detecting the amount of ultraviolet light directly incident from the ultraviolet light source 51. In order to input as much ultraviolet light as possible that is not incident on the processing flow path L, the second detector 9 is arranged at a position where the light emitting surface of the ultraviolet light source 51 and the light receiving surface of the second detector 9 are as close as possible.

Further, a shielding member (second ultraviolet shielding object) 10 is provided between the open end of the housing 4 and the second detector 9. The shielding member 10 has, for example, a plate shape, and is provided in a portion including a region where the light receiving surface of the second detector 9 and the end portion of the processing flow path L overlap when viewed from the substrate 53 side. The shielding member 10 may be a member having a diffusion transmittance of 0.5% or less, and for example, a metal such as aluminum or stainless steel, or an LED substrate material such as FR4 can be applied. The second detector 9 outputs a voltage signal or a current signal according to the amount of ultraviolet light. The detection signal of the second detector 9 is input to the control device 7.

The second detector 9 may be a detector having the same performance as that of the first detector 6 or may be different. Further, since the second detector 9 can be provided in the vicinity of the ultraviolet light source 51 together with the first detector 6, as shown in FIG. 11, the second detector 9 is mounted on the ultraviolet light source 51 together with the first detector 6. It may be mounted on the mounted substrate 53, or may be mounted on a different substrate.
The shielding member 10 prevents the ultraviolet light reflected by the processing flow path L from being incident on the second detector 9 from the end of the housing 4 when the second detector 9 is attached to the substrate 53. It is provided for this purpose. The shielding member 10 may have a shape and an arrangement position that can prevent ultraviolet light emitted from the opening of the housing 4 from being incident on the second detector 9, and is further incident on the first detector 6. The amount of ultraviolet light reflected from the processing flow path L may be a shape and an arrangement position that can be the amount of light necessary for determining whether or not sufficient ultraviolet irradiation is performed for sterilization.

The control device 7 drives and controls the ultraviolet light source 51 and receives the detection signal of the first detector 6. The light source is driven and controlled so that the irradiation target is irradiated with a preset amount of ultraviolet light. It is also possible to drive the ultraviolet light source 51 with a constant current and issue an alarm when the threshold value of the detection signal set in advance is exceeded. When the control device 7 predicts that the sterilization performance has deteriorated based on the detection signal of the first detector 6, the cause of the deterioration of the sterilization performance is caused by using the detection signal of the second detector 9. It is determined whether or not this is due to a decrease in the amount of light emitted from the ultraviolet light source 51. For example, in the control device 7, when the ultraviolet light source 51 is irradiating the amount of light corresponding to the drive signal, whether or not the amount of light emitted by the ultraviolet light source 51 is reduced by the amount of light detected by the second detector 9. To judge. Thereby, it is determined whether or not the cause of the decrease in the light emission amount detected by the first detector 6 is caused by the decrease in the light emission amount of the ultraviolet light source 51.

As described above, in the ultraviolet irradiation device 1-3 according to the third embodiment, since the second detector 9 detects the amount of ultraviolet light directly incident from the ultraviolet light source 51, the amount of light detected by the first detector 6 is It is possible to easily determine whether or not the decrease is due to a decrease in the amount of light emitted from the ultraviolet light source 51 itself, and it is possible to obtain an effect equivalent to that in the third embodiment, and further. , The cause of deterioration of sterilization performance can be quickly identified.
Further, since the ultraviolet light source 51, the first detector 6 and the second detector 9 can be mounted on one substrate 53, it is realized without significantly increasing the size of the entire ultraviolet irradiation device 1-3. be able to.

In FIG. 7, the ultraviolet light source 51, the first detector 6, and the second detector 9 are mounted on one board 53, but these may be mounted on different boards. Further, in FIG. 7, the case where the second detector 9 is provided in the ultraviolet irradiation device 1-2 of the second embodiment to isolate the cause of the deterioration of the sterilization performance has been described, but the ultraviolet irradiation device of the first embodiment has been described. It is also possible to apply to 1-1.

<Fourth Embodiment>
FIG. 8 is a vertical cross-sectional view showing an example of a schematic configuration of an ultraviolet irradiation device according to a fourth embodiment of the present invention. The ultraviolet irradiation device 1-4 according to the fourth embodiment is the ultraviolet ray disclosed in, for example, Patent Document 4 as the first detector 6 and the second detector 9 in the ultraviolet irradiation device 1-3 according to the third embodiment. Photodetectors 71a, 71b, which are photodetectors having an ultraviolet light-excited phosphor composed of a fluorescent glass element or the like and a photodetector composed of a photodetector for detecting the emission intensity of the ultraviolet light-excited phosphor, such as a light emitting device. Is used. The light detection units 71a and 71b detect the fluorescence intensity as a value equivalent to the amount of ultraviolet light, and manage the light emitting state of the ultraviolet light source 51 based on the detected fluorescence intensity and the temperature detected by the temperature sensor 115 described later. It is monitored by 111, and the management circuit 111 suppresses the deterioration of the parts used for the light detection units 71a and 71b and the deterioration of the electronic parts group 1100 described later such as other electronic parts while maintaining the light emission intensity of the ultraviolet light source 51. The ultraviolet light source 51 is driven and controlled so as to extend the service life.

As shown in FIG. 8, the ultraviolet irradiation device 1-4 according to the fourth embodiment replaces the first detector 6 and the second detector 9 in the ultraviolet irradiation device 1-3 according to the third embodiment. It includes light detection units 71a and 71b. Further, the ultraviolet irradiation device 1-4 includes an inner cylinder 201 in which the hollow portion forms the processing flow path L and an outer cylinder 202 accommodating the inner cylinder 201, as in the ultraviolet irradiation device disclosed in Patent Document 5, for example. The lid portion 203 for closing one end of the inner cylinder 201, the irradiation portion 204 including the ultraviolet light source 51 provided at the other end of the inner cylinder 201, and the opening end of the inner cylinder 201 on the lid portion 203 side are provided so as to close. A disk-shaped rectifying plate 205 for rectifying the fluid flowing into the inner cylinder 201 is provided. In the ultraviolet irradiation device 1-4, an annular ring 206 is provided between the inner cylinder 201 and the outer cylinder 202, and the gap between the inner cylinder 201 and the outer cylinder 202 is divided into two sections. Then, the irradiation object flowing in from the inflow port 207 passes through one of the compartments 202a, passes through the communication hole 201a formed between the lid portion 203 and the inner cylinder 201, and passes through the rectifying plate 205 into the inner cylinder 201. Introduced in. A convex portion (not shown) is formed on the lid portion 203, and the convex portion and the end portion of the inner cylinder 201 are in contact with each other to position the inner cylinder 201 in the outer cylinder 202.

The irradiation target passes through the processing flow path L, passes through the communication hole 201b formed near the end of the inner cylinder 201 on the irradiation portion 204 side, and enters the other compartment 202b between the inner cylinder 201 and the outer cylinder 202. It has been introduced so that it can be discharged from the output port 208. The straightening vane 205 does not necessarily have to be provided.

FIG. 9 is a configuration diagram showing the details of the irradiation unit 204, in which the irradiation unit 204 includes a window unit 204a holding a window 210 for partitioning the processing flow path L and the ultraviolet light source 51, the ultraviolet light source 51, and light. It includes a light source unit 204b that holds the detection units 71a and 71b. The ultraviolet light-excited phosphors 71aa and 71ba of the photodetectors 71a and 71b have, for example, a spherical shape, and are excited by the incident ultraviolet light to emit fluorescence. The photodetectors 71ab and 71bb of the photodetectors 71a and 71b are composed of, for example, a photodiode as a photodetector, and convert the fluorescence emitted from the ultraviolet photoexcited phosphors 71aa and 71ba into an electric current and output it to the management circuit 111. ..
The light source unit 204b includes a substrate 61 on which the ultraviolet light source 51 is mounted, a first holding unit 62 for accommodating the substrate 61, a second holding unit 63, and photodetectors 71ab and 71bb of the photodetectors 71a and 71b. The substrate 64 to be formed is provided. The outer diameters of the window portion 204a and the first holding portion 62 are the same.

An ultraviolet light source 51 is arranged in the center of the substrate 61, a through hole 61a for incident ultraviolet light reflected in the processing flow path L for the photodetector 71a, and an ultraviolet light-excited phosphor of the photodetector 71b. A through hole 61b into which the 71ba is fitted is formed. The through hole 61a is formed at a position on the substrate 61 where the ultraviolet light reflected in the processing flow path L is incident, but the ultraviolet light irradiated by the ultraviolet light source 51 is not directly incident.
The first holding portion 62 has an annular shape and has an inner diameter capable of accommodating the substrate 61 on which the ultraviolet light source 51 is mounted. A shielding member 65 is provided on the inner circumference of the first holding portion 62.
The shielding member 65 is provided at a position capable of preventing ultraviolet light reflected in the processing flow path L from being incident on the ultraviolet light-excited phosphor 71ba fitted in the through hole 61b.

On the surface of the second holding portion 63 facing the first holding portion 62, a recess 63a into which the ultraviolet light-excited phosphor 71aa of the photodetector 71a is fitted is provided at a position facing the through hole 61a when viewed from the ultraviolet light source 51 side. A recess 63b for storing the photodetector 71ab of the photodetector 71a is formed on the surface of the second holding portion 63 opposite to the first holding portion 62. Further, a communication hole 63c that serves as an optical path between the ultraviolet light-excited phosphor 71aa and the photodetector 71ab is provided between the recess 63a and the recess 63b of the second holding portion 63.
At a position of the second holding unit 63 facing the through hole 61b when viewed from the ultraviolet light source 51 side, the photodetector 71bb of the photodetector unit 71b is stored on the surface opposite to the substrate 61 and serves as an optical path. A recess 63d is formed, and a communication hole 63e that serves as an optical path between the ultraviolet light-excited phosphor 71ba and the photodetector 71bb is formed on the surface on the substrate 61 side.

Then, the window portion 204a, the first holding portion 62, and the second holding portion 63 are integrally fixed by fixing them with bolts and nuts from the second holding portion 63 side. By fixing the substrate 64 to the second holding portion 63 with bolts and nuts (not shown) in a state where the recesses 63b and 63d of the second holding portion 63 integrally fixed and the photodetectors 71ab and 71bb face each other. The window portion 204a, the first holding portion 62, the second holding portion 63, and the substrate 64 are integrally fixed. Further, by fixing the flange portion 202c, the window portion 204a, and the first holding portion 62 formed at the end of the outer cylinder 202 on the irradiation portion 204 side with bolts and nuts from the first holding portion 62 side, the irradiation portion 204 is fixed to the outer cylinder 202.

As a result, only the ultraviolet light reflected from the processing flow path L is incident on the through hole 61a formed in the substrate 61 and is incident on the ultraviolet light-excited phosphor 71aa, and the fluorescence emitted by the ultraviolet light-excited phosphor 71aa is emitted through the communication hole 63c. It is incident on the recess 63b through the recess 63b, and the light intensity of fluorescence is detected by the light detector 71ab. Further, the ultraviolet light-excited phosphor 71ba provided on the substrate 61 is incident with ultraviolet light that does not pass through the object to be irradiated among the ultraviolet light irradiated by the ultraviolet light source 51, and the reflected light from the processing flow path L is the shielding member 65. Since it is shielded by the ultraviolet light-excited phosphor 71ba, it is not incident on the ultraviolet light-excited phosphor 71ba. Then, the ultraviolet light incident on the ultraviolet light-excited phosphor 71ba causes the ultraviolet light-excited phosphor 71ba to emit fluorescence, and the emitted fluorescence is incident on the recess 63d through the communication hole 63e, and the light intensity of the fluorescence is detected. Detected by vessel 71bb.
The ultraviolet irradiation device 1-4 includes photodetectors 71ab, 71bb, a management circuit 111, and a temperature sensor 115 as electronic components, and these photodetectors 71ab, 71bb, a management circuit 111, and a temperature sensor 115 are electronic components. It constitutes 1100.

FIG. 10 shows an example of the circuit configuration of the management circuit 111. The management circuit 111 may be provided on the surface of the substrate 64 opposite to the surface on which the photodetectors 71ab and 71bb are provided, or may be provided as a separate body.
As shown in FIG. 10, the management circuit 111 sets the setting circuits (setting units) 111aa and 111ab for setting the target value for emitting the ultraviolet light source 51 at a desired emission intensity, and sets the ultraviolet light source 51 to a desired emission intensity. It has an automatic power control (Auto Power Control: APC) circuit (automatic power control unit) 111b to be maintained. The target values set by the setting circuits 111aa and 111ab are the current values of the drive current of the ultraviolet light source 51. Further, the management circuit 111 has a light emitting element drive circuit (drive unit) 111c that drives the ultraviolet light source 51.

The setting circuit 111aa is a circuit that sets a target value based on the detection signal of the light detection unit 71a, and the setting circuit 111ab is a circuit that sets the target value based on the detection signal of the light detection unit 71b. Since the functional configurations of the setting circuits 111aa and 111ab are the same, the setting circuit 111aa will be described here. The detection signal of the photodetector 71ab is input to the setting circuit 111aa via the IV conversion circuit 1114a, and the detection signal of the photodetector 71bb is input to the setting circuit 111ab via the IV conversion circuit 1114b. ..

The setting circuit 111aa includes an amplification unit 1110 that amplifies the voltage based on the detection signal of the optical detector 71ab, a bias adjustment unit 1111 that adjusts the DC bias of the output voltage output by the amplification unit 1110, and an output output by the amplification unit 1110. It has an offset adjusting unit 1112 that adjusts the offset voltage included in the voltage. Further, the setting circuit 111aa has an addition unit 1113 that adds the output voltage of the amplification unit 1110, the output voltage of the bias adjustment unit 1111 and the output voltage of the offset adjustment unit 1112.

The output terminal of the current / voltage conversion circuit 1114a provided in the automatic power control circuit 111b is connected to the input terminal of the amplification unit 1110. The output terminal of the amplification unit 1110 is connected to one of the three input terminals of the addition unit 1113. The output terminal of the bias adjusting unit 1111 is connected to one of the remaining terminals of the adding unit 1113, and the output terminal of the offset adjusting unit 1112 is connected to the other of the remaining terminals of the adding unit 1113. The output terminal of the addition unit 1113 is connected to the input terminal of the analog / digital conversion unit 1115 (details will be described later) provided in the automatic power control circuit 11b. A predetermined output terminal of the microprocessor 1116 (details will be described later) provided in the automatic power control circuit 111b is connected to the input terminal to which the input bit signal of the bias adjusting unit 1111 is input. A predetermined output terminal of the microprocessor 1116 is connected to the input terminal to which the input bit signal of the offset adjustment unit 1112 is input.

The amplifier section 1110 is composed of, for example, a programmable gain amplifier (PGA). The amplification unit 1110 amplifies the input voltage input from the current / voltage conversion circuit 1114a and outputs it to the addition unit 1113. Although details will be described later, the amplification factor (gain) of the amplification unit 1110 may be abbreviated as a target drive current for causing the ultraviolet light source 51 to emit light at a desired emission intensity (hereinafter, referred to as “target drive current of the ultraviolet light source 51”). It is adjusted as necessary at the time of setting (there is) and at the start of operation of the ultraviolet light source 51.

The bias adjusting unit 1111 is composed of, for example, a digital / analog conversion circuit (Digital to Analog Converter: DAC). In the present embodiment, the bias adjusting unit 1111 is composed of a DAC for the upper 8 bits and a DAC for the lower 8 bits. Therefore, the bias adjusting unit 1111 can adjust the output voltage output from the amplification unit 1110 by 16 bits or the like. As a result, the bias adjusting unit 1111 adjusts the bias with sufficient resolution even if the amount of light detected by the photodetector 71ab of the photodetector 71a that detects only the amount of reflected light from the processing flow path L is small. Can be done. The number of input bits of the bias adjusting unit 1111 is not limited to 16 bits, and may be appropriately set according to the amount of light detected by the photodetector 71ab. Although the details will be described later, the output voltage (that is, the input bit value) of the bias adjusting unit 1111 is adjusted as necessary when the operation of the ultraviolet light source 51 is started.

The offset adjusting unit 1112 is composed of, for example, a digital / analog conversion circuit (Digital to Analog Converter: DAC). In the present embodiment, the offset adjusting unit 1112 is composed of a DAC for the upper 8 bits and a DAC for the lower 8 bits. Therefore, the offset adjustment unit 1112 can offset the output voltage output from the amplification unit 1110 with 16 bits or the like. As a result, the offset adjusting unit 1112 can adjust the offset with sufficient resolution even if the amount of the detected light detected by the photodetector 71ab is small. The number of input bits of the offset adjusting unit 1112 is not limited to 16 bits, and may be appropriately set according to the amount of light detected by the photodetector 71ab. The offset adjusting unit 1112 is used to adjust the offset voltage generated in the entire circuit constituting the ultraviolet irradiation device 1-4. Although the details will be described later, the output voltage (that is, the input bit value) of the offset adjusting unit 1112 is adjusted as necessary when setting the target drive current of the ultraviolet light source 51.

The addition unit 1113 is configured to output an addition voltage obtained by adding the output voltage of the amplification unit 1110, the output voltage of the bias adjustment unit 1111 and the output voltage of the offset adjustment unit 1112 to the automatic power control circuit 111b. That is, the addition unit 1113 has a configuration of 3 inputs and 1 output. The adder 1113 may have various circuit configurations. For example, the adder 1113 has two operational amplifiers with two inputs and one output, one operational amplifier adds the output voltage of the bias adjustment unit 1111 and the output voltage of the offset adjustment unit 1112, and the other operational amplifier outputs the output of one operational amplifier. It may be configured to add the voltage and the output voltage of the amplification unit 1110. When the target drive current of the ultraviolet light source 51 is set, the addition unit 1113 finally outputs a voltage based on the emission intensity of the ultraviolet light source 51 driven by the target drive current as a feedback voltage Vfb. Further, the addition unit 1113 outputs a voltage based on the emission intensity of the ultraviolet light source 51 as a feedback voltage Vfb during the sterilization operation of the object to be sterilized by the ultraviolet light source 51.

As shown in FIG. 10, the automatic power control circuit 111b has a current / voltage (hereinafter, may be referred to as “IV”) conversion circuit 1114a and 1114b in which an input terminal is connected to the anode of the photodetector 71ab. ing. Although detailed description of the circuit configuration will be omitted, the IV conversion circuits 1114a and 1114b are configured by using, for example, a current input type operational amplifier. The output terminal of the IV conversion circuit 1114a is connected to the non-inverting input terminal of the amplification unit 1110 provided in the setting circuit 111aa. The IV conversion circuit 1114a converts the current input from the photodetector 71ab into a voltage and outputs it to the amplification unit 1110 of the setting circuit 111aa. The IV conversion circuit 1114b converts the current input from the photodetector 71bb into a voltage and outputs it to the amplification unit 1110 of the setting circuit 111ab.

The automatic power control circuit 111b has an analog / digital conversion unit (hereinafter, "analog / digital" may be abbreviated as "A / D") 1115a that converts an analog signal output from the setting circuit 111aa into a digital signal. , An analog / digital converter (hereinafter, "analog / digital" may be abbreviated as "A / D") 1115b, which converts an analog signal output from the setting circuit 111ab into a digital signal. .. Further, the automatic power control circuit 111b includes a microprocessor (determination unit) 1116 that determines whether or not the ultraviolet light source 51 maintains a desired emission intensity based on the digital signal converted by the A / D conversion unit 1115a. Have. Further, the automatic power control circuit 111b generates a pulse width modulation (PWM) signal (an example of a control signal) that controls the light emitting element drive circuit (drive unit) 111c based on an instruction from the microprocessor 1116. It has a pulse width modulation signal generation unit (generation unit) 1117. In FIG. 10, the microprocessor is represented as "μP". Further, hereinafter, pulse width modulation may be abbreviated as "PWM". Although the details will be described later, the automatic power control circuit 111b determines whether or not the ultraviolet light source 51 is operating at a desired emission intensity based on the feedback voltage Vfb during the sterilization operation.

The output terminals of the A / D converters 1115a and 1115b are connected to predetermined input terminals to which the bit signal of the microprocessor 1116 is input. A predetermined output terminal of the microprocessor 1116 is connected to an input terminal of the PWM signal generation unit 1117. The output terminal of the PWM signal generation unit 1117 is connected to the input terminal of the control unit 1118 (details will be described later) provided in the light emitting element drive circuit 111c.

The Analog to Digital Converter (ADC) 1115a converts the feedback voltage Vfb of the analog signal input from the addition unit 1113 provided in the setting circuit 111aa into a digital signal and outputs it to the microprocessor 1116. The A / D conversion unit 1115b converts the feedback voltage Vfb of the analog signal input from the addition unit 1113 provided in the setting circuit 111ab into a digital signal and outputs it to the microprocessor 1116.

The microprocessor 1116 stores the digital signal input from the A / D conversion unit 1115a as the target code in a predetermined storage area when the setting of the target drive current of the ultraviolet light source 51 is completed. This target code is a condition of the driving current for driving the ultraviolet light source 51 with a desired emission intensity. After storing the target code, the microprocessor 1116 stores the allowable operating range of the ultraviolet light source 51 as a threshold code in a predetermined storage area. The microprocessor 1116 sets an upper limit threshold code that defines the upper limit of the allowable operating range of the ultraviolet light source 51 and a lower limit threshold code that defines the lower limit.

The microprocessor 1116 compares the digital signal input from the A / D conversion unit 1115a with the target code and the threshold code during the sterilization operation of the object to be sterilized by the ultraviolet light source 51. When the value of the input digital signal is a value included between the target code and the threshold code, the microprocessor 1116 determines that the ultraviolet light source 51 maintains a desired emission intensity. On the other hand, the microprocessor 1116 determines that the ultraviolet light source 51 does not maintain the desired emission intensity when the value of the input digital signal is a value not included between the target code and the threshold code. .. When the microprocessor 1116 determines that the ultraviolet light source 51 maintains a desired emission intensity, the microprocessor 1116 does not output a special instruction signal to the PWM signal generation unit 1117. On the other hand, when it is determined that the ultraviolet light source 51 does not maintain the desired emission intensity, the microprocessor 1116 outputs an instruction signal instructing the PWM signal generation unit 1117 to change the drive current. When the value of the input digital signal is larger than the upper limit threshold code, the microprocessor 1116 outputs an instruction signal instructing the current amount of the drive current to be reduced to the PWM signal generation unit 1117. On the other hand, when the value of the input digital signal is smaller than the lower limit threshold code, the microprocessor 1116 outputs an instruction signal instructing to increase the current amount of the drive current to the PWM signal generation unit 1117. In this way, the ultraviolet irradiation device 1-4 feeds back the emission intensity of the ultraviolet light source 51 during the sterilization operation of the object to be sterilized by the ultraviolet light source 51, and controls the ultraviolet light source 51 to maintain the desired emission intensity.

As shown in FIG. 10, a state identification signal Mode is input to the microprocessor 1116. The state identification signal Mode is a signal for identifying whether the operating state of the ultraviolet irradiation devices 1-4 is driving the ultraviolet light source 51 by the feedback control or driving the ultraviolet light source 51 with an installed constant current. When the state identification signal Mode is "0", the microprocessor 1116 determines that, for example, the ultraviolet light source 51 is driven by the feedback control. On the other hand, when the state identification signal Mode is "1", the microprocessor 1116 determines that, for example, the ultraviolet light source 51 is driven by a constant current with a set current.

That is, the microprocessor 1116 can select the driving method of the ultraviolet light source 51 based on the signal level of the state identification signal Mode. Here, when the external light is incident, the external light and the fluorescence emitted by the ultraviolet light-excited phosphor 71aa are incident on the photodetector 71ab. Since the fluorescence emitted by the ultraviolet light-excited phosphor 71aa is several orders of magnitude different from that of external light, for example, when the output of the photodetector 71ab exceeds the output upper limit of the photodetector 71ab, external light is incident. Can be determined. Therefore, when the management circuit 111 operates the ultraviolet light source 51 in a state where the object to be sterilized can be sterilized, if it is determined that external light is incident on the photodetector 71ab for some reason, the ultraviolet light is emitted. The operation of the light source 51 is stopped. The management circuit 111 immediately stops the ultraviolet light source 51 when the ultraviolet irradiation devices 1-4 are used abnormally. As a result, the ultraviolet irradiation device 1-4 can prevent the ultraviolet rays from leaking to the outside when the object to be sterilized is sterilized.

Further, in the microprocessor 1116, when the output of the photodetector 71ab is not the amount of light emitted corresponding to the target irradiation amount, the output of the photodetector 71bb input from the A / D conversion unit 1115b corresponds to the target irradiation amount. It is determined whether or not it is the amount of light emitted. When the output of the photodetector 71bb, that is, the actual amount of light emitted from the ultraviolet light source 51 is not the amount of light emitted corresponding to the target irradiation amount, the factor that the output of the photodetector 71ab does not become the amount of light emitted corresponding to the target irradiation amount is ultraviolet rays. It is determined that this is caused by a decrease in the amount of light emitted from the light source 51. Further, when the output of the photodetector 71bb is a light emission amount corresponding to the target irradiation amount, the factor that the output of the photodetector 71ab does not become the light emission amount corresponding to the target irradiation amount is the reflectance in the processing flow path L. It is determined that the cause is a decrease or a change in the transmittance of the internal fluid, and for example, the determination result is displayed on a display device (not shown) or the like. This determination process may be executed periodically when the sterilization operation state is in effect, and the difference between the output of the photodetector 71ab and the amount of light emitted corresponding to the target irradiation amount is set in advance. It may be executed only when it is larger than the value.

The PWM signal generation unit 1117 outputs the duty signal Sduty to the light emitting element drive circuit 111c based on the instruction signal input from the microprocessor 1116. When the instruction signal instructing to reduce the drive current is input from the microprocessor 1116, the PWM signal generation unit 1117 emits a duty signal Sduty having a duty ratio smaller than the duty signal Sduty output immediately before. Output to the element drive circuit 111c. On the other hand, when the instruction signal instructing to increase the drive current is input from the microprocessor 1116, the PWM signal generation unit 1117 has a duty signal Sduty having a duty ratio larger than the duty signal Sduty output immediately before. Is output to the light emitting element drive circuit 111c.

The ultraviolet irradiation device 1-4 includes a temperature sensor (temperature detection unit) 115 that detects the temperature of the ultraviolet light source 51. The temperature sensor 115 is mounted on a substrate 61 on which, for example, an ultraviolet light source 51 is mounted. The automatic power control circuit 111b controls the light emitting element drive circuit 111c based on the temperature detected by the temperature sensor 115. The output terminal of the temperature sensor 115 is connected to a predetermined input terminal of the microprocessor 1116.

The temperature sensor 115 has, for example, a thermistor and a resistor connected in series with an analog power supply and an analog reference potential (analog ground). Further, the temperature sensor 115 has a comparator that compares the voltage at the connection point between the thermistor and the resistor with a predetermined voltage. The output terminal of this comparator serves as the output terminal of the temperature sensor 115. Further, this predetermined voltage is set to a voltage corresponding to a predetermined temperature (for example, 80 ° C.) of the ultraviolet light source 51. When the temperature of the ultraviolet light source 51 detected by the thermistor is lower than the predetermined temperature, the temperature sensor 115 outputs, for example, a low level (0 V) voltage from the comparator to the microprocessor 1116. On the other hand, when the temperature of the ultraviolet light source 51 detected by the thermistor is higher than the predetermined temperature, the temperature sensor 115 is subjected to, for example, a high level voltage from the comparator (a high level of the input voltage allowed by the microprocessor 1116). Voltage) is output to the microprocessor 1116.

The microprocessor 1116 instructs the PWM signal generation unit 1117 to change the duty ratio of the duty signal Sduty according to the voltage level of the voltage input from the temperature sensor 115. The microprocessor 1116 does not instruct the PWM signal generation unit 1117 to change the duty ratio of the duty signal Sduty when a low level voltage is input from the temperature sensor 115. On the other hand, the microprocessor 1116 instructs the PWM signal generation unit 1117 to increase the duty ratio of the duty signal Sduty when a high level voltage is input from the temperature sensor 115. As a result, the amount of drive current flowing through the ultraviolet light source 51 increases, so that the emission intensity reduced due to the high temperature of the ultraviolet light source 51 is compensated. As described above, the ultraviolet irradiation devices 1-4 can compensate for the decrease in the emission intensity due to the temperature characteristics of the ultraviolet light source 51, separately from the decrease in the emission intensity due to the deterioration of the ultraviolet light source 51 over time (details will be described later).

Further, the microprocessor 1116 is adapted to change the input bit values of the bias adjusting unit 1111 and the offset adjusting unit 1112 as necessary. Further, the microprocessor 1116 is adapted to change the amplification factor of the amplification unit 1110 as necessary when the target drive current of the ultraviolet light source 51 is set.

As shown in FIG. 10, the light emitting element drive circuit 111c has a control unit 1118 and a constant current source 1119. The control unit 1118 controls the amount of current output by the constant current source 1119 based on the duty signal Sduty input from the PWM signal generation unit 1117. When the duty ratio of the duty signal Sduty input from the PWM signal generation unit 1117 becomes small, the control unit 1118 drives the constant current source 1119 so that the amount of the output current becomes small. On the other hand, when the duty ratio of the duty signal Sduty input from the PWM signal generation unit 1117 becomes large, the control unit 1118 drives the constant current source 1119 so that the amount of the output current becomes large.

An ultraviolet light source 51 is connected in series to the constant current source 1119. The positive electrode of the constant current source 1119 is connected to the cathode of the ultraviolet light source 51, and the negative electrode of the constant current source 1119 is connected to the analog reference potential (analog ground). The constant current source 1119 is controlled by the control unit 1118 to output a constant current of a predetermined amount of current from the analog power supply toward the analog ground. Since the ultraviolet light source 51 is connected in series with the constant current source 1119, a constant current of the amount of current output by the constant current source 1119 flows through the ultraviolet light source 51. The voltage value of the analog power supply applied to the anode of the ultraviolet light source 51 is constant. Therefore, the intensity of the ultraviolet rays emitted by the ultraviolet light source 51 is determined by the amount of constant current output by the constant current source 1119.

Next, the operation of the ultraviolet irradiation device 1-4 will be described with reference to FIGS. 8 to 10 with reference to FIGS. 11 to 13. 11 and 13 or 12 and 13 show the operations of the ultraviolet irradiation devices 1-4 in this order in chronological order. The time scales shown in FIGS. 11 to 13 are shown differently from the actual scales. Further, in FIGS. 11 and 12, the number of fluctuations in the feedback voltage Vfb does not match the actual number of bits, and a part of the feedback voltage Vfb is abbreviated by a straight arrow.

The ultraviolet irradiation device 1-4 has a target value setting state for setting the target drive current of the ultraviolet light source 51 and a feedback control state for controlling the output of the photodetector 71ab so that the light emission amount corresponds to the target irradiation amount. It works in two states. In the target value setting state, the ultraviolet irradiation device 1-4 executes four steps to set the target value of the ultraviolet light source 51 (in the present embodiment, the target value of the current amount of the drive current of the ultraviolet light source 51).
First, in the target value setting state, the initial value of the amplification factor of the amplification unit 1110 is set to the maximum value. Further, the input bit value is set so that the initial value of the output voltage of the bias adjusting unit 1111 is 1/2 of the maximum voltage VDD. Further, the input bit value is set so that the initial value of the output voltage of the offset adjusting unit 1112 is 1/2 of the maximum voltage VDD. Further, the state identification signal Mode is set to "1".

After the above initial setting is completed, as shown in FIG. 11, at time t0, the operation of the setting circuit 111aa and the automatic power control circuit 111b is started without operating the ultraviolet light source 51. Since the ultraviolet light source 51 is in a non-operating state, fluorescence does not occur in the ultraviolet light-excited phosphor 71aa, but for example, a dark current flows through the photodetector 71ab, so that a current is input from the photodetector 71ab to the IV conversion circuit 1114. NS. Since the amplification factor of the amplification unit 1110 is set to the maximum value, the feedback voltage Vfb is output from the addition unit 1113. At time t1, the feedback voltage Vfb becomes a value larger than the maximum voltage VDD.

When the feedback voltage Vfb having a value larger than the maximum voltage VDD is output from the addition unit 1113, the microprocessor 1116 reduces the amplification factor of the amplification unit 1110 by one step in the first step. Each time the amplification factor of the amplification unit 1110 is reduced, the microprocessor 1116 determines whether or not the feedback voltage Vfb has dropped to the input voltage VIN1 on the high level side where the operation of the microprocessor 1116 is compensated. The microprocessor 1116 reduces the amplification factor of the amplification unit 1110 until it is determined that the feedback voltage Vfb has dropped to the input voltage VIN1.

For example, when the feedback voltage Vfb becomes lower than the input voltage VIN1 at time t2, then in the second step, the microprocessor 1116 inputs in order to lower the output voltage of the DAC for the high-order bit provided in the offset adjustment unit 1112. Change the bit value bit by bit. In the microprocessor 1116, each time the input bit value of the high-order bit DAC is changed by 1 bit, the voltage value of the feedback voltage Vfb becomes a value in the range from 1/2 of the maximum voltage VDD to the error voltage (VDD / 2 + ΔV). Determine if it is. After that, when the microprocessor 1116 determines that the voltage value of the feedback voltage Vfb is in the range from 1/2 of the maximum voltage VDD to the error voltage (VDD / 2 + ΔV) at time t3, for example, the offset adjustment unit 1112 The change of the input bit value of the DAC for the upper bit is completed.

Next, the ultraviolet irradiation device 1-4 again executes the first step and the second step in order to adjust the offset voltage by the lower bit DAC provided in the offset adjusting unit 1112. At time t3, the management circuit 111 sets the amplification factor of the amplification unit 1110 to the maximum value again. As a result, at time t4, the feedback voltage Vfb becomes a value larger than the maximum voltage VDD.
When a feedback voltage Vfb having a value larger than the maximum voltage VDD is output from the adder 1113, in the first step, the management circuit 111 gradually reduces the amplification factor of the amplification unit 1110 and sets the feedback voltage Vfb to the microprocessor 1116. The input voltage on the high level side where the operation of is compensated is lowered to VIN1.

For example, when the feedback voltage Vfb becomes lower than the input voltage VIN1 at time t5, then, in the second step, the management circuit 111 inputs so that the output voltage of the lower bit DAC provided in the offset adjusting unit 1112 decreases. Change the bit value. After that, at time t6, when the voltage value of the feedback voltage Vfb becomes a value in the range from 1/2 of the maximum voltage VDD to the error voltage (VDD / 2 + ΔV), the management circuit 111 is used for the lower bits of the offset adjustment unit 1112. The change of the input bit value of the DAC is finished.

FIG. 11 shows an example in which the feedback voltage Vfb becomes a voltage value larger than the maximum voltage VDD when the operation of the setting circuit 111a and the automatic power control circuit 111b is started in the target value setting state. May be a voltage value smaller than the minimum voltage (0V).
As shown in FIG. 12, at time t0, the operation of the setting circuit 111a and the automatic power control circuit 111b is started without operating the ultraviolet light source 51. Since the ultraviolet light source 51 is in a non-operating state, fluorescence does not occur in the ultraviolet light-excited phosphor 71aa, but for example, a dark current flows through the photodetector 71ab, so that a current is input from the photodetector 71ab to the IV conversion circuit 1114. NS. Since the amplification factor of the amplification unit 1110 is set to the maximum value, the feedback voltage Vfb is output from the addition unit 1113. At time t1, the feedback voltage Vfb becomes a value smaller than the minimum voltage (0V).

When a feedback voltage Vfb having a value smaller than the minimum voltage (0V) is output from the adder 1113, in the first step, the management circuit 111 gradually reduces the amplification factor of the amplification unit 1110 and sets the feedback voltage Vfb to micro. The input voltage VIN2 on the low level side where the operation of the processor 1116 is compensated is raised.
For example, when the feedback voltage Vfb becomes higher than the input voltage VIN2 at time t2, the microprocessor 1116 then inputs in the second step to increase the output voltage of the high-order bit DAC provided in the offset adjustment unit 1112. Change the bit value bit by bit. After that, at time t3, when the microprocessor 1116 determines that the voltage value of the feedback voltage Vfb is a value in the range from 1/2 of the maximum voltage VDD to the error voltage (VDD / 2-ΔV), the offset adjustment unit 1112 The change of the input bit value of the DAC for the upper bit of is completed.

Next, the ultraviolet irradiation device 1-4 again executes the first step and the second step in order to adjust the offset voltage by the lower bit DAC provided in the offset adjusting unit 1112. At time t3, the management circuit 111 sets the amplification factor of the amplification unit 1110 to the maximum value again. As a result, at time t4, the feedback voltage Vfb becomes a value smaller than the minimum voltage (0V).
When a feedback voltage Vfb having a value smaller than the minimum voltage (0V) is output from the adder 113, in the first step, the microprocessor 1116 reduces the amplification factor of the amplification unit 1110 step by step to reduce the feedback voltage Vfb. The input voltage VIN2 on the low level side where the operation of the microprocessor 1116 is compensated is increased.

For example, when the feedback voltage Vfb becomes higher than the input voltage VIN2 at time t5, then in the second step, the microprocessor 1116 raises the output voltage of the lower bit DAC provided in the offset adjustment unit 1112. The input bit value is changed bit by bit. After that, at time t6, when the voltage value of the feedback voltage Vfb becomes a value in the range from 1/2 of the maximum voltage VDD to the error voltage (VDD / 2-ΔV), the input of the lower bit DAC of the offset adjustment unit 1112 Finish changing the bit value.
The period P1 and the period P3 shown in FIGS. 11 and 12 correspond to the first step of adjusting the amplification factor of the amplification unit 1110. The period P2 and the period P4 shown in FIGS. 11 and 12 correspond to a second step of adjusting the offset voltage included in the entire circuit constituting the ultraviolet irradiation device 1-4 by using the offset adjusting unit 1112.

Next, at time t7, the amplification factor of the amplification unit 1110 and the input bit values of the bias adjustment unit 1111 and the offset adjustment unit 1112 in the target value setting state are maintained in the state where the second second step is completed. , A current as an initial value is passed through the ultraviolet light source 51. As a result, the ultraviolet light source 51 starts operating and irradiates ultraviolet light. Since the ultraviolet light-excited phosphor 71aa is excited by the ultraviolet light incident from the ultraviolet light source 51 to generate fluorescence, a current is input from the photodetector 71ab to the IV conversion circuit 1114. In this case, the current flowing from the photodetector 71ab to the IV conversion circuit 1114 is several orders of magnitude larger than the dark current. Therefore, at time t8, the feedback voltage Vfb output from the addition unit 1113 becomes a value larger than the maximum voltage VDD.

When the feedback voltage Vfb having a value larger than the maximum voltage VDD is output from the adder 1113, in the third step, the microprocessor 1116 reduces the amplification factor of the amplification unit 1110 by one step, and sets the feedback voltage Vfb to the microprocessor. The operation of 1116 is reduced to the compensated high level input voltage VIN1.

For example, when the feedback voltage Vfb becomes lower than the input voltage VIN1 at time t9, then in the fourth step, the microprocessor 1116 reduces the output voltage of the DAC provided in the bias adjusting unit 1111 in order to reduce the input bit value. Is changed bit by bit. After that, when the voltage value of the feedback voltage Vfb becomes a value in the range from 1/2 of the maximum voltage VDD to the error voltage (VDD / 2 + ΔV) at time t10, the DAC input bit value of the bias adjustment unit 1111 is changed. finish. The microprocessor 1116 stores the digital signal obtained by A / D conversion of the feedback voltage Vfb at time t10 by the A / D conversion unit 1115 in a predetermined storage area as a target code. Further, the microprocessor 1116 sets the upper limit threshold code and the lower limit threshold code in a predetermined storage area based on the stored target code. As a result, the ultraviolet irradiation devices 1-4 complete the initial setting operation by the setting circuit 111aa. The microprocessor 1116 performs the initial setting operation by the setting circuit 111ab in the same procedure.

The period P5 shown in FIG. 13 corresponds to the third step of adjusting the amplification factor of the amplification unit 1110 in a state where a current as an initial value is passed through the ultraviolet light source 51. The period P6 shown in FIG. 13 corresponds to the fourth step of adjusting the DC bias included in the feedback voltage Vfb in a state where a current as an initial value is passed through the ultraviolet light source 51.
The ultraviolet irradiation device 1-4 sets the state identification signal Mode to "0" when the initial setting operation by the setting circuits 111aa and 111ab is completed. When the ultraviolet irradiation device 1-4 starts sterilizing the object to be sterilized at the subsequent time t11 and the ultraviolet light source 51 continues to emit light, the ultraviolet light source 51 deteriorates with time and the voltage-current characteristic changes. As a result, at time t12, the feedback voltage Vfb becomes lower than the lower limit threshold voltage VthL corresponding to the lower limit threshold code.

The microprocessor 1116 determines that the value of the digital signal input from the A / D conversion unit 1115 is smaller than the lower limit threshold code, and the ultraviolet light source 51 does not maintain the desired emission intensity. Therefore, the microprocessor 1116 outputs an instruction signal for increasing the drive current of the ultraviolet light source 51 to the PWM signal generation unit 1117. When the instruction signal is input, the PWM signal generation unit 1117 generates a duty signal Sduty having a duty ratio larger than that of the duty signal Sduty corresponding to the target code and outputs the duty signal Sduty to the light emitting element drive circuit 111c. As a result, the amount of current output by the constant current source 1119 increases, so that the current flowing through the ultraviolet light source 51 also increases.

By repeating the operation for changing the duty ratio of the duty signal Sduty in the automatic power control circuit 111b, the amount of the drive current flowing through the ultraviolet light source 51 increases, and the emission intensity becomes desired at, for example, at time t13. Return to. As a result, the feedback voltage Vfb exceeds 1/2 of the maximum voltage VDD, so that the value of the digital signal input from the A / D converter 1115 of the microprocessor 1116 is within the range of the upper limit threshold coat and the lower limit threshold code. Therefore, it is determined that the ultraviolet light source 51 maintains a desired emission intensity. Then, the microprocessor 1116 does not output the instruction signal for increasing the drive current of the ultraviolet light source 51 to the PWM signal generation unit 1117. As a result, the PWM signal generation unit 1117 continuously outputs the duty signal Sduty of the duty ratio that was output immediately before to the light emitting element drive circuit 111c. As a result, the amount of current output by the constant current source 1119 is maintained, and the amount of current flowing through the ultraviolet light source 51 is also maintained. Therefore, the ultraviolet light source 51 maintains a desired emission intensity. In this way, in the ultraviolet irradiation device 1-4, the microprocessor 1116 can detect and compensate for the deterioration of the ultraviolet light source 51 with time.

It is assumed that the feedback voltage Vfb is lower than the lower limit threshold voltage VthL at time t14, for example, by continuing the operation of the ultraviolet irradiation devices 1-4 after the time t13. Then, the ultraviolet irradiation device 1-4 executes the same operation as the operation from the time t12 to the time t13. As a result, at time t15, the feedback voltage Vfb exceeds 1/2 of the maximum voltage VDD, and the ultraviolet light source 51 again emits light with a desired emission intensity.
The ultraviolet irradiation device 1-4 initially sets the operating point of the ultraviolet light source 51 so that the emission intensity is not the maximum emission intensity of the ultraviolet light source 51 but the minimum emission intensity necessary for sterilizing the object to be sterilized. Therefore, even if the ultraviolet light source 51 deteriorates with time, the ultraviolet irradiation device 1-4 can repeatedly perform the operation compensation of the ultraviolet light source 51 until the operating point after compensation reaches the operating point of the maximum emission intensity.

Further, the ultraviolet irradiation device 1-4 adjusts the offset voltage of the entire circuit constituting the ultraviolet irradiation device 1-4 in the target value setting state to set the feedback voltage Vfb to 1/2 of the maximum voltage VDD. As a result, even if the voltage fluctuates in the sterilization operation state, the possibility that the feedback voltage Vfb becomes larger than the maximum voltage VDD or smaller than the minimum voltage (0V) is extremely low. As a result, the ultraviolet irradiation devices 1-4 can stabilize the sterilization operation.

Although not shown, after the operation of the ultraviolet light source 51 is started (after time t11 in FIG. 13), external light is incident into the housing of the ultraviolet irradiation device 1-4 for some reason, and the light detector 71ab When external light is incident on the surface together with the fluorescence emitted by the ultraviolet light-excited phosphor 71aa, the amount of external light is several orders of magnitude larger than the amount of fluorescence emitted by the ultraviolet light-excited phosphor 71aa. Therefore, the feedback voltage Vfb is higher than the maximum voltage VDD. Prior to the start of operation of the ultraviolet light source 51, a state identification signal Mode having a value of "0" is input to the microprocessor 1116. Therefore, the management circuit 111 forcibly sets the voltage value of the feedback voltage Vfb input to the A / D conversion unit 1115 to 0V, or controls the duty signal Sduty having a duty ratio of 0 in the light emitting element drive circuit 111c. The operation of the ultraviolet light source 51 is stopped by inputting to the unit 1118. As a result, the ultraviolet irradiation devices 1-4 can prevent the ultraviolet rays from leaking to the outside.

As described above, in the state where the ultraviolet light source 51 is driven and controlled based on the feedback voltage Vfb from the setting circuit 111aa, the microprocessor 1116 is based on the output of the light detector 71ab input from the A / D conversion unit 1115a. When it is determined that the ultraviolet light source 51 does not maintain the desired light emission intensity, whether or not the output of the light detector 71bb input from the A / D conversion unit 1115b is the amount of light emission corresponding to the desired light emission intensity. When the light emission amount does not correspond to the desired light emission intensity, for example, the difference between the light emission amount corresponding to the desired light emission intensity and the light emission amount corresponding to the detection signal of the light detector 71bb is equal to or larger than a preset threshold value. When this is the case, it is determined that the reason why the output of the light detector 71ab does not have a light emission amount corresponding to the desired light emission intensity is caused by a decrease in the light emission amount of the ultraviolet light source 51. On the other hand, when the output of the photodetector 71bb input from the A / D conversion unit 1115b is the light emission amount corresponding to the desired light emission intensity, the output of the photodetector 71ab is the light emission amount corresponding to the desired light emission intensity. It is determined that the cause of the failure is a change in the reflectance in the processing flow path L or the transmittance of the irradiated object. Then, the determination result is displayed on, for example, a display device (not shown). The user of the ultraviolet irradiation device 1-4 refers to the determination result displayed on the display device or the like, and the decrease in the light emission amount of the ultraviolet light source 51 is due to the decrease in the light emission amount of the ultraviolet light source 51. It can be easily determined whether it is due to a change in the reflectance in the processing flow path L or the transmittance of the irradiated object.

As described above, the ultraviolet irradiation device 1-4 according to the fourth embodiment is a light detection device that detects ultraviolet light reflected from the processing flow path, similarly to the ultraviolet irradiation device 1-3 according to the third embodiment. A unit 71a and a light detection unit 71b for detecting the amount of ultraviolet light directly incident from a light source that does not pass through an object to be irradiated are provided. Therefore, in this case as well, the same effect as that of the third embodiment can be obtained. Further, the ultraviolet irradiation device 1-4 according to the fourth embodiment determines the intensity of the fluorescence emitted by the ultraviolet light-excited phosphors 71aa and 71ba and the ultraviolet light-excited phosphors 71aa and ba that emit fluorescence in the visible light region by the excitation of ultraviolet light. Since various light amounts are detected by the light detectors 71ab and 71bb for detection, a detector for detecting various light amounts can be installed in the limited space of the irradiation unit 204.

Further, the management circuit 111 automatically learns the initial value of the drive current of the ultraviolet light source 51, and if the deterioration with time of the ultraviolet light source 51 is within the expected range, the emission intensity (output power) of the ultraviolet light source 51 becomes constant. Since the ultraviolet light source 51 is driven as described above, the irradiation performance of ultraviolet light can be further stabilized.

Although the embodiment of the present invention has been described above, the above-described embodiment illustrates an apparatus or method for embodying the technical idea of the present invention, and the technical idea of the present invention is a component component. It does not specify the material, shape, structure, arrangement, etc. of The technical idea of the present invention may be modified in various ways within the technical scope specified by the claims stated in the claims.

1-1, 1-2, 1-3, 1-4 Ultraviolet irradiation device 2 Inflow part 3 Outflow part 4 Housing 5 Irradiation part 6 First detector 7, 7a Control device 8 Shielding member 9 Second detector 10 Shielding Member 51 Ultraviolet light source 65 Shielding member 71a, 71b Light detector 71a, 71ba Photodetector 71ab, 71bb Photodetector 111 Management circuit 115 Temperature sensor 201 Inner cylinder 202 Outer cylinder 202a, 202b Section 204 Irradiation unit 205 rectifying plate 207 flow Inlet 208 Output port 210 Window 1100 Electronic component group L Processing flow path

Claims (11)

Toward the object which has an ultraviolet reflective material at least in a part and is provided at least one of a processing flow path through which the object passes and one end or the other end of the processing flow path and passes through the processing flow path. An ultraviolet light source that irradiates ultraviolet light and
A light amount detection unit including a first detector for detecting the amount of ultraviolet light arranged at the end of the processing flow path on the side where the ultraviolet light source is provided, and
A first ultraviolet shield arranged on a straight line connecting the light emitting surface of the ultraviolet light source and the light receiving surface of the first detector, and
UV irradiation device with. The ultraviolet irradiation according to claim 1, wherein the light amount detecting unit further includes a second detector that detects the amount of ultraviolet light of the ultraviolet light source without an ultraviolet shield between the light emitting surface and the light receiving surface of the ultraviolet light source. Device. 2. The second aspect of the present invention, wherein the second ultraviolet ray shield is provided between the processing flow path and the second detector and shields the reflected light from the processing flow path that is about to reach the second detector. UV irradiation device. The detector included in the light amount detection unit is a fluorescence detector having an ultraviolet light-excited phosphor that is excited by ultraviolet light and emits visible light and a light detector that detects the intensity of fluorescence emitted by the ultraviolet light-excited phosphor. The ultraviolet irradiation device according to any one of claims 1 to 3, wherein the intensity of the fluorescence is detected as a value corresponding to the amount of ultraviolet light. Equipped with a group of electronic components having multiple electronic components
From claim 1, the electronic component group includes a management circuit that is composed of at least a part of the plurality of electronic components and manages the ultraviolet light source based on the amount of ultraviolet light detected by a detector included in the light intensity detection unit. The ultraviolet irradiation device according to any one of claims 4. The management circuit
A setting unit for setting a target value for emitting the ultraviolet light source with a desired emission intensity, and a setting unit.
An automatic power control unit that maintains the ultraviolet light source at the desired emission intensity, and
The ultraviolet irradiation device according to claim 5. The setting unit
An amplification unit that amplifies the voltage based on the detection signal of the detector included in the light intensity detection unit, and
A bias adjustment unit that adjusts the DC bias of the output voltage output by the amplification unit, and
An offset adjustment unit that adjusts the offset voltage included in the output voltage output by the amplification unit, and an offset adjustment unit.
The ultraviolet irradiation device according to claim 6, further comprising an adder that adds the output voltage of the amplification unit, the output voltage of the bias adjustment unit, and the output voltage of the offset adjustment unit. The management circuit has a drive unit that drives the ultraviolet light source, and has a drive unit.
The automatic power control unit includes an analog / digital conversion unit that converts an analog signal output from the setting unit into a digital signal.
A determination unit that determines whether or not the ultraviolet light source maintains the desired emission intensity based on the digital signal converted by the analog / digital conversion unit.
The ultraviolet irradiation device according to claim 6 or 7, further comprising a generation unit that generates a control signal for controlling the drive unit based on an instruction from the determination unit. The ultraviolet irradiation device according to claim 8, further comprising a temperature detection unit that detects the temperature of the ultraviolet light source, and the automatic power control unit controls the drive unit based on the temperature detected by the temperature detection unit. The management circuit
When the output of the detector included in the light amount detection unit exceeds the output upper limit value of the detector included in the light amount detection unit set in advance, it is determined that external light has been incident and the operation of the ultraviolet light source is stopped. The ultraviolet irradiation device according to any one of claims 5 to 9. The ultraviolet irradiation device according to any one of claims 1 to 10, which is an ultraviolet irradiation device for a fluid sterilizer that irradiates a fluid as an object with ultraviolet rays.

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