JPH09201406A - Ozone sterilizing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely decompose ozone to a level which less affects human health by stopping an ozone decomposing treatment in an ozone decomposing unit after continuing the ozone decomposition for a given time when an ozone sensor comes to a not-detecting state after the ozone decomposing unit begins ozone decomposing treatment. SOLUTION: A first ozone sensor 39 for detecting a residual ozone concentration in a sterilizing space is installed and when the second ozone sensors 39 and 35 for detecting leakage of ozone in an atmospheric environment 31 detect a higher concentration of ozone than a given standard concentration, switches 'ON' and when it detects lower ozone concentration than the level, it switchs 'OFF', and the standard concentration is given to be a slightly higher than time concentration in the natural air. The ozone is decomposed by an ozone decomposing catalyst 10 and when each of the ozone sensor 39 and 35 comes to OFF, the ozone decomposition treatment is still continued for another time and then stopped. Therefore, an ozone concentration not affecting the human health can be surely kept.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ozone sterilizer for supplying ozone to a space to be sterilized to sterilize an item contained in the space to be sterilized.

[0002]

2. Description of the Related Art Recently, the present applicant has considered a method of controlling an ozone sterilizer using an ozone sensor capable of detecting low-concentration ozone. This is an ozone sterilization apparatus including at least an ozone generating unit that supplies ozone to the sterilized space and an ozone decomposing unit that decomposes ozone supplied to the sterilized space. Ozone is supplied to the sterilization unit, and when the sterilization is completed, the ozone decomposing unit is operated to gradually decompose the ozone in the sterilized space, and the ozone concentration in the sterilized space becomes an ozone concentration (0.1 ppm or less) that does not affect the human body. After the fact is recognized using the ozone sensor, the operation of the ozone sterilizer is promptly stopped.

Specifically, the concentration detection level at which the ozone sensor is turned on and off is set to, for example, 0.05 ppm, and the ozone decomposing section is continuously operated until the ozone concentration decreases to this level, and the ozone concentration is 0.05 ppm. When the control unit detects that the ozone sensor is in the non-detection state, the operation of the ozone sterilizer is considered to be stopped.

The ozone sensor for detecting the ozone concentration in the space to be sterilized has a predetermined level of ozone even after the power is turned on, even before the operation switch for starting the sterilization process is turned on or after the ozone is decomposed. If it is detected, or if the ozone sterilizer is stopped during operation and the device is stopped due to an accident and residual ozone is detected after returning, it can be used for abnormality determination to force the ozone decomposition process. Used.

[0005]

However, as described above, the ozone concentration detection level is set to 0.0 which does not affect the human body.
In the case of setting to 5 ppm, when the door of the sterilized space is opened after the ozone decomposition is completed, ozone existing in the atmosphere enters the sterilized space, and the ozone concentration of the invaded air happens to be the concentration of the ozone sensor. If it exceeds the detection level, there is a malfunction that the ozone decomposition process is forcibly performed by entering the abnormal processing mode even though the ozone decomposition process is completed.

Actually, the ozone concentration in the air in the natural world is often close to or higher than 0.1 ppm depending on various conditions such as season, environment and time zone.
If the door is opened in such an atmosphere, there is a disadvantage that the ozone decomposition treatment is continued forever.

Therefore, in the present invention, when ozone in the atmosphere enters the sterilized space by opening and closing the door while having a function of surely decomposing ozone in the sterilized space to a level that does not affect the human body. Another object of the present invention is to provide an ozone sterilizer that does not malfunction.

[0008]

In order to achieve the above object, the ozone sterilizer of the present application decomposes ozone supplied to the sterilized space and an ozone generator for generating ozone to be supplied to the sterilized space. Regarding what is provided with at least an ozone decomposing unit, in response to the ozone concentration of the sterilized space,
An ozone sensor that becomes a non-detection state when the concentration is lower than the ozone concentration in the air outside the sterilized space is set, and the ozone sensor does not detect after the decomposition process is started by the ozone decomposition unit. When it becomes a state,
It is characterized in that the ozone decomposing portion is made to stop after the ozone decomposing process is continued for a predetermined time (Claim 1).

Here, the concentration set higher than the ozone concentration in the air outside the space to be sterilized means that the ozone concentration in the atmosphere which fluctuates depending on various conditions such as season, environment, time zone, etc. Is a concentration that is set to be large, and a typical concentration is, for example, about 0.15 ppm. Therefore, an ozone sensor for detecting a low concentration that reacts with an ozone concentration of several ppm or less is sufficient.

Further, the time for continuing the decomposition process after the ozone sensor is in the non-detection state is set to a time sufficient for the ozone concentration in the sterilized space to decrease to a concentration that does not affect the human body. Since the size varies depending on the size of the sterilized space, the predetermined time for continuing the decomposition process may be changed according to the size of the sterilized space (claim 2).

Therefore, according to the present invention, when the ozone decomposition treatment is performed to end the ozone sterilization, the ozone concentration in the sterilized space gradually decreases, and when the ozone concentration becomes equal to or lower than the set concentration, the ozone concentration is reduced. The sensor goes into non-detection state. Then, when the ozone sensor enters the non-detection state, the ozone decomposition process does not end at that point, but stops after continuing for a predetermined time set in advance.

Further, since the set concentration at which the ozone sensor is in the non-detection state is set to be slightly higher than the ozone concentration in the air outside the sterilized space, the sterilized space is set after the ozone decomposition process is completed. Even if the door is opened and closed and the outside air enters the space, the ozone sensor does not react with the ozone in the air.

[0013]

Embodiments of the present invention will be described below with reference to the drawings.

In FIG. 1, an ozone sterilization apparatus 1 according to the present invention is arranged outside a sterilized space 2 including a pass box, a safety cabinet, etc., and comprises an sterilized space 2, an intake duct 3 and a delivery duct 4. It is connected and sucks air from the sterilized space 2 and sends out the sucked air to the space.

As shown concretely in FIGS. 2 and 3, the ozone sterilizer 1 has an inflow / outflow space 5 defined therein by a corrosion resistant material such as stainless steel. The inflow / outflow space 5 includes an intake side space portion 6 and a delivery side space portion 7, and these space portions are communicated with each other via a communication portion facing the blower 8. The blower 8 is composed of, for example, a sirocco fan arranged in the sending side space 7, and sucks the air in the intake side space 6 and sends the air to the sending side space 7 under pressure.

The air intake side space portion 6 communicates with the sterilized space 2 through an air intake duct 3 connected to a duct connection portion 9 formed in the upper portion thereof, and the duct connection portion 9 causes the blower 8 to be communicated.
The first passage 11 where the ozone decomposition catalyst 10 such as activated carbon is arranged and the second passage 12 which bypasses the ozone decomposition catalyst 10 are divided. A first opening / closing damper 13 for opening / closing the first passage 11 is provided further upstream of the ozone decomposition catalyst in the first passage 11, and a second opening / closing damper for opening / closing the second passage is provided in the second passage 12. A damper 14 is provided.

The space 7 on the delivery side communicates with the space 2 to be sterilized through a blower duct 4 connected to a duct connecting portion 15 formed on the upper side thereof. Further, to the space 7, an outward path 17 and a return path 18 leading to the humidifier 16 are connected, and an ozone supply path 19 for supplying ozone is also connected.

The humidifier 16 is for giving humidity to the sending side space 7 in order to enhance the sterilization effect by ozone, and when the power source 20 is turned on, the water in the water tank 21 is atomized by using ultrasonic waves. The air is converted into air and discharged into the air sent through the outward path 17, and the air having the humidity is supplied to the delivery side space 7 through the return path 18.

The ozone generator 22 includes an ozonizer 29 having a discharge electrode and a high-voltage power supply 30 for applying a high voltage to the discharge electrode, and a manual valve 24 provided in an oxygen supply passage from an oxygen cylinder 23 and a cylinder attached thereto. Regulator 25, oxygen regulator 26, oxygen supply solenoid valve 2
7. Oxygen is supplied to the ozonizer 29 via the oxygen flow rate control valve 28, the ozonizer 29 is discharged to convert the oxygen supplied thereto into ozone, and the ozone is supplied from the ozone supply passage 19 to the space 7 on the delivery side. It is supposed to be supplied.

The humidifier 16 and the ozone generator 22 are located outside the inflow / outflow space 5 in the apparatus (atmosphere atmosphere area 3).
1), and the ventilation fan 32 and the control unit 33 for controlling each device are further arranged in this portion. The ventilation fan 32 sucks and discharges the outside air through a ventilation hole 34 formed in the wall surface of the device to positively ventilate the inside of this area, and each device (humidifier 16 and ozonizer 29) arranged here. , Various power sources 20, 30,
It has a function of cooling the control unit 33, etc.).

In the sterilized space 2, a first ozone sensor 39 for detecting the concentration of ozone remaining in this space is provided.
In addition, a second ozone sensor 35 that detects ozone leakage is provided in each of the air atmosphere regions 31. Of these, the first ozone sensor 39 may be arranged in the inflow / outflow space 5, but the ozone gas has a property that diffusion and concentration distribution greatly differ depending on the size of the space, the sterilization symmetrical substance, the amount of the sterilization symmetrical substance, etc. Ideally, it should be placed directly in the space to be sterilized 2 because it will be decomposed when passing through 3 or the like and the concentration will decrease. Therefore, in this embodiment, as shown in FIG. 3, the first ozone sensor 39 is provided near the opening of the suction duct 3 (shown by a solid line) or at an arbitrary position in the sterilized space 2 (shown by a broken line). ).

First and second ozone sensors 39, 35
Is a thin-film semiconductor sensor that turns on when ozone of a predetermined reference concentration or higher is detected, and turns off when the ozone concentration is lower than the predetermined reference concentration. A value whose concentration is slightly higher than the ozone concentration in the air in the natural world α
(For example, 0.15 ppm) is set.

The control unit 33 is provided with a microcomputer, a memory, an I / O, a drive circuit for driving and controlling various operating devices, etc., and when the power switch 40 is turned on, the first and second ozone sensors 35, 36, etc. The actuators 37 and 38 for inputting various information and driving the first and second opening / closing dampers 13 and 14 according to a predetermined program, the blower 8, the ventilation fan 32, the oxygen supply solenoid valve 27, the humidifier 16, and the ozone. It controls various operating devices such as the generator 22.

In FIG. 4, the control unit 33
An example of the overall operation of the ozone sterilization apparatus 1 is shown. When the ozone sterilization apparatus 1 is activated by turning on the power switch 40, the ozone sterilization apparatus 1 enters a standby mode of waiting for the input of an operation switch (not shown) that starts ozone sterilization (step 50). ), And then enters the start mode in which preparation for exercise for generating ozone is performed by turning on the operation switch (step 5).
2).

In this start mode, the solenoid valve 27 for oxygen supply is opened to supply oxygen to the ozonizer 29, the ventilation fan 32 is rotated to start ventilation, and an AC voltage (AC100V) is supplied to the high-voltage power supply 30. Then, the command from the control unit 33 allows the ozonizer 29 at any time.
A standby state in which a high voltage can be applied is formed. Further, in this start mode, the first opening / closing damper 13 is closed and the second opening / closing damper 14 is opened so that the duct connection portion 9 and the blower 8 are connected by the second passage 12.

After the start mode is performed for a predetermined time,
The ozone sterilizer automatically enters the ozone generation / humidification mode (step 54), and in this mode, the control unit 33 rotates the blower 8 to cause the space 2 to be sterilized.
The air is sucked into the intake side space 6 of the inflow / outflow space 5 via the intake duct 3 and returned to the sterilized space 2 from the delivery side space 7 via the delivery duct 4 to form a recirculation state. Further, a high voltage is applied to the ozonizer 29 from the high voltage power source 30 to start the discharge, and ozone is generated from the supplied oxygen. The ozone generated here is supplied to the delivery side space portion 7 through the ozone supply passage 19, mixed with the air sucked from the sterilized space 2, and returned to the sterilized space 2 through the delivery duct 4. . The air in the sterilized space 2 repeats such a mixing process with ozone, and as shown by the solid line in FIG.
Increase ozone concentration to over 200ppm. At the same time, the humidifier 16 is operated to increase the efficiency of ozone sterilization, and the humidity of the space 2 to be sterilized is increased to 80% RH or more as shown by the broken line in FIG.

The time for operating the ozonizer 29 and the humidifier 16 may be set manually, or
It may be one which automatically sets to calculate an increase slope of the ozone concentration and humidity, 20 in the sterilization space of about 8m ³
In order to obtain an ozone concentration of 0 ppm or higher and a humidity of 80% RH or higher, an ozonizer having an ozone generation capacity of about 6 g / h and a humidifier that generates 0.4 liters / h of steam are each used for 1 hour. Just activate it.

After activating the ozonizer 29, and after a lapse of time for obtaining the concentration and humidity above the specified values (after 60 minutes in this embodiment), the ozonizer 29 and the humidifier 16 are stopped, and the ozone sterilizer operates. From the ozone generation mode to the fumigation and sterilization mode (step 56). In this mode,
The blower 8 is stopped, the sterilized space 2 is left with the ozone concentration and humidity kept high, and the ozonizer 29 is stopped and then the oxygen supply solenoid valve 27 is closed and the ventilation fan 32 is stopped. , AC voltage to the high voltage power source 30 (AC10
The supply of 0 V) is stopped and the second opening / closing damper 14 is closed. This fumigation and sterilization mode is carried out for about 2 hours, after which the ozone sterilizer enters the ozone decomposition and termination mode (step 58).

A concrete operation example of the ozone decomposition / termination mode is shown in FIG. 6, and when the control unit 33 enters this mode, the blower 8 is turned on, the first opening / closing damper 13 is opened, and the second opening / closing damper 13 is opened. The opening / closing damper 14 is closed, and the ozone-containing air that recirculates by communicating between the duct connection portion 9 and the blower 8 through the first passage 11 is passed through the ozone decomposition catalyst 10 (step 60). As a result, the ozone-containing air circulates between the sterilized space 2 and the inflow / outflow space 5, and the ozone content rate decreases each time it passes through the ozone decomposition catalyst 10. It gradually decreases as shown by the solid line of 5.

In the control unit 33, the ozone concentration in the sterilized space 2 is gradually decreased and α (= 0.15 pp)
m) or less, and it is determined whether or not the first ozone sensor 39 outputs an off signal (step 62).
When the ozone sensor 39 is turned off, it is determined whether or not a predetermined time T has elapsed from that point (step 64).
When a predetermined time T elapses after the first ozone sensor 39 is turned off, the first opening / closing damper 13 is closed, the second opening / closing damper 14 is closed, and the blower 8 is turned off to end the operation not shown. Perform sterilization termination processing such as turning on the lamp and turning off the fumigation lamp (step 6).
6) Then, the process again shifts to the standby mode of step 50.

The predetermined time T from when the first ozone sensor 39 is turned off to when step 66 is executed is such that the ozone concentration in the sterilized space 2 has a low concentration γ which does not affect the human body.
The time is sufficient to reach (= 0.05 ppm or less), and can be changed according to the size of the sterilized space 2. For example, the predetermined time T may be manually set according to the size of the sterilized space 2, or the size of the sterilized space 2 may be determined from the ozone concentration and the rising gradient of humidity in the ozone generation / humidification mode. The time may be automatically set according to the estimated size.

Further, the control unit 33 shifts to the abnormal processing mode when the ozone sensor is turned on in the standby mode, or when an unexpected situation such as a power failure occurs in each of the processing modes described above and then the system is restored. Has become
When this abnormality processing mode is entered, the blower is turned on to remove the residual ozone in the sterilized space 2, and the first opening / closing damper 1
3 is opened and the second opening / closing damper 14 is closed to perform ozone decomposition processing and other processing.

In the above structure, the first ozone sensor 3
Since the ON / OFF reference concentration of 9 is set to around 0.15 ppm, which is higher than the ozone concentration in the air in the natural world, it is assumed that the ozone decomposition process is stopped when the ozone sensor is turned off as in the conventional case. If you do, the space to be sterilized 2
Since the ozone concentration of is higher than the ozone concentration in the atmosphere, it is not preferable for the human body even though it is low, but according to the present invention, when the first ozone sensor 39 is turned off, the size of the space 2 to be sterilized is then reduced. The ozone decomposition treatment is continued for a predetermined time T set according to the above, and the ozone concentration in the sterilized space 2 is set to a concentration γ that does not affect the human body (for example, 0.05 p
pm) or less.

By the way, if the door of the space to be sterilized 2 is opened and closed after the ozone decomposition process, outside air enters the space to be sterilized 2. The ozone concentration β of the invading air is sterilized by the environment as described above. It may become higher than the ozone concentration γ of the space 2. However, since the ON / OFF reference concentration α of the first ozone sensor 39 is set to be higher than the ozone concentration β in the air, the first ozone sensor 39 reacts with ozone in the atmosphere. ON
Therefore, there is no risk of malfunction such as entering the abnormal processing mode and performing ozone decomposition processing again.

The second ozone sensor 35 is also directly exposed to the atmosphere, but since the ON / OFF reference concentration α is set higher than the ozone concentration β in the air in the natural world, it reacts with ozone in the natural world. There is nothing to do. Therefore, the second ozone sensor 35 can be appropriately reacted only to ozone leakage, and a highly reliable ozone sterilizer can be provided.

[0036]

As described above, according to the present invention,
The ozone sensor set concentration is set higher than the ozone concentration in the air outside the sterilized space, and after the ozone sensor is in the non-detection state during the ozone decomposition process, the ozone decomposition process is continued for a predetermined time and then the ozone Since the decomposition process is stopped, the ozone concentration in the sterilized space can be reliably reduced to a level that does not affect the human body, as in the conventional case.

Although the ozone concentration in the atmosphere may increase due to various conditions such as season, environment and time zone,
Assuming that such air enters the space to be sterilized by opening and closing the door, if the ozone detection concentration of the ozone sensor is set to a low concentration that does not affect the human body, residual ozone will remain in the space to be sterilized. There is a case in which a malfunction such as forcibly disassembling and forcibly disassembling occurs. However, in the present invention, since the ozone detection concentration of the ozone sensor is set higher than this in anticipation of the ozone concentration in the atmosphere which fluctuates under the above-mentioned conditions, malfunction of the ozone sterilizer can be prevented. .

[Brief description of drawings]

FIG. 1 is a diagram showing a state in which an ozone sterilizer according to the present invention and a space to be sterilized are connected by a duct.

FIG. 2 is a schematic diagram showing a configuration of an ozone sterilizer.

FIG. 3 is a diagram showing the vicinity of a duct connection between an ozone sterilizer and a space to be sterilized.

FIG. 4 is a flowchart showing an overall operation example of sterilization processing by the ozone sterilization apparatus according to the present invention.

FIG. 5 is a diagram showing an ozone generation / humidification mode for sterilization treatment,
It is a diagram which shows the change of the ozone concentration and humidity of the to-be-sterilized space in each process of a fumigation sterilization mode and an ozone decomposition / completion | finish mode.

FIG. 6 is a flowchart showing a specific control operation example in the ozone decomposition / termination mode.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ozone sterilizer 2 Sterilized space 10 Ozone decomposition catalyst 13 First opening / closing damper 14 Second opening / closing damper 22 Ozone generator 35 Second ozone sensor 39 First ozone sensor

Claims (2)

[Claims] 1. An ozone sterilizer comprising at least an ozone generator for generating ozone supplied to a sterilized space and an ozone decomposing unit for decomposing ozone supplied to the sterilized space, wherein ozone in the sterilized space is provided. In response to the concentration, an ozone sensor that is in a non-detection state when the concentration is lower than the ozone concentration in the air outside the sterilized space is set, and after the decomposition process is started by the ozone decomposition unit, An ozone sterilizer, characterized in that, when the ozone sensor is in a non-detection state, the ozone decomposing unit stops the ozone after the ozone decomposing process is continued for a predetermined time. 2. The ozone sterilizer according to claim 1, wherein the predetermined time for continuing the ozone decomposition treatment is changed according to the size of the sterilized space.