JPH10314281A - Ozone sterilizer - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To be able to decompose ozone to a safe concentration to some extent even when an ozone sensor has failed. SOLUTION: An ozone concentration in a sterilization booth 2 is detected by an ozone sensor 13, and a detection signal VS of a voltage value corresponding to the ozone concentration is output. Microcomputer device 22
Is executed when the operation of the ozonolysis step after the operation of the apparatus is started is satisfied when two or more of the three end conditions are satisfied. The first termination condition is when a voltage value corresponding to the environmental reference value is output from the ozone sensor 13,
The second termination condition is when the operation time of the ozonolysis step is N times longer than the time required for the ozone generation step, and the third termination condition is that the high-concentration ozone sensor 30 detects the predetermined concentration during the ozonolysis step. This is the time when a specified time has elapsed since the ozone was detected.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ozone sterilizing apparatus for performing ozone sterilizing treatment by sending ozone-containing air into a sterilizing booth.

[0002]

2. Description of the Related Art An ozone sterilizing apparatus has a sterilizing booth and an ozone generator. A chamber provided adjacent to the sterilizing booth sucks air in the sterilizing booth and generates ozone in the air sucked into the chamber. The ozone concentration in the sterilization booth is set to a predetermined value by repeating mixing of the ozone from the vessel and exhausting to the sterilization booth, and sterilization is performed in the sterilization booth. Then, when the sterilization process is completed, a process of sucking ozone-containing air having a higher concentration than the sterilization booth into the chamber again, decomposing ozone with the ozonolysis catalyst, and then exhausting the ozone to the sterilization booth is repeated. Post-treatment is performed to reduce the concentration to a level that does not affect the human body, for example, an environmental standard value of less than 0.1 ppm. Then, whether or not the ozone concentration has dropped to a level that does not affect the human body is detected by an ozone sensor provided in the chamber. Therefore, this ozone sensor must react to extremely low concentration of ozone (less than 0.1 ppm) in order to determine the end of the ozonolysis operation, but such an ozone sensor capable of detecting low concentration is currently cost-effective. However, in terms of shape, it is practically limited to semiconductor type ozone sensors.

[0003]

In order to use the output of such an ozone sensor for safe operation of the apparatus, for example, at the start of operation, the ozone concentration in the apparatus based on the output of the ozone sensor is lower than the environmental standard value. After confirming the above, start the operation of the device, and at the end of the operation, perform the ozone decomposition operation until the ozone concentration in the device becomes lower than the environmental standard value based on the output of the ozone sensor. A safe driving system for terminating the operation of the device when it is confirmed that the condition has been established is considered.

A specific example of this kind of safe driving system is configured such that a semiconductor type ozone sensor outputs an output voltage of a level corresponding to an ozone concentration, and a reference voltage corresponding to an environmental reference value (0.1 ppm) set in the device. A configuration is considered in which the output voltage is compared with the output voltage to determine whether the ozone sensor is normal at the start of operation of the apparatus. That is, when the output voltage from the ozone sensor is a voltage value lower than the reference voltage, it is determined that the ozone sensor is normal and the operation of the apparatus is started. On the other hand, when the output voltage of the ozone sensor is higher than the reference voltage at the start of the operation, the ozone sensor is determined to be abnormal and the operation is not started. This is because in such a situation, it cannot be guaranteed that the ozone concentration after the end of the ozonolysis operation becomes lower than the environmental standard.

[0005] In the above-mentioned safe driving system, before the operation is started, the ozone sensor is in an ordinary environment in which the ozone concentration is extremely low, and the ozone concentration should naturally be lower than the environmental standard value. The detection of the ozone concentration level value is based on the assumption that the ozone sensor is considered to be abnormal. However, with the above configuration, it is not possible to detect whether the resistance value (output voltage value) of the ozone sensor changes corresponding to the ozone concentration that changes to a high concentration after the start of operation. Even when the ozone sensor is determined to be normal, it is not possible to determine until the subsequent detection operation of the ozone sensor is normal. As described above, the ozone sensor is indispensable to ensure the safety of the operation of the ozone sterilizer, and its reliability is strongly required.

The semiconductor type ozone sensor has a high concentration (about 10 ppm) in principle due to its ozone detection mechanism.
The above-mentioned characteristics are difficult to recover when exposed to ozone. On the other hand, this sensor can be exposed to high concentrations (about 200 ppm) of ozone in the chamber during the sterilization operation. Therefore, the characteristics of the semiconductor type ozone sensor may be deteriorated while the device is used, and a detection value different from the true ozone concentration may be output.
As a result, it may hinder the management of the ozone concentration in the ozone sterilizing apparatus. For example, when the safe driving system as described above is employed, the output of the ozone sensor may be different from the true value and may reduce the reliability of the apparatus. was there. Further, when the detection value of the ozone sensor becomes abnormal, there is a possibility that the operation of the ozone sterilization apparatus cannot be started or ended.

Accordingly, an object of the present invention is to provide an ozone sensor capable of decomposing ozone to a safe concentration to a certain degree even in a situation where an ozone sensor has failed, thereby ensuring a safer operation. It is to provide a sterilization device.

[0008]

According to a first aspect of the present invention, there is provided a sterilization booth, an ozone generator, and ozone from the ozone generator supplied to air in the sterilization booth during sterilization. And an ozone generation step of increasing the ozone concentration in the sterilization booth to a predetermined concentration for sterilization, a fumigation sterilization step of maintaining the sterilization environment generated in the ozone generation process for a predetermined period, and the sterilization after the sterilization is completed. An ozone sterilization apparatus having a processing chamber in which an ozone decomposition process for returning the ozone concentration of the air in the booth to a safe low level is sequentially executed, and outputs a detection signal of a level corresponding to the ozone concentration in the sterilization booth. A first ozone sensor capable of detecting low-concentration ozone, and a detection signal of a level corresponding to the ozone concentration in the sterilization booth. A second ozone sensor for detecting ozone having a higher concentration than the first ozone sensor, and a detection signal output from the first ozone sensor during the operation of the ozone decomposing step is a safe signal. First end condition processing means for setting that the first condition relating to the end of the operation of the ozonolysis step is satisfied by detecting whether or not the ozone generation step has been reached; A second operation for detecting an operation time and setting that a second condition for terminating a required operation time of the ozone decomposition step determined based on the operation time of the ozone generation step is satisfied.
Terminating condition processing means, and when the detection signal output from the high-concentration ozone sensor during operation of the ozonolysis step has dropped to a level corresponding to a level slightly higher than the safe low level, A third ending condition processing unit that determines the remaining operation time of the process and sets that the third condition relating to the end of the operation of the ozonolysis process is satisfied, and each of the first to third ending condition processing units. A termination permitting means for permitting termination of the ozonolysis step when at least two or more termination conditions are satisfied based on the setting state of the termination condition.

According to this configuration, the ozonolysis step performed after the sterilization processing of the ozone sterilization apparatus is completed can be completed only when two or more of the three ending conditions are satisfied. That is, the end of the ozone decomposition operation is not determined only by the detection value of the ozone sensor,
This is set as a first end condition, and in addition, a second end condition indicating the end of the operation time of the ozone decomposition process based on the operation time of the ozone generation process and a detection signal output from the high-concentration ozone sensor are determined by a predetermined value. The operation of the ozonolysis step is terminated when two or more of the third termination conditions for ending the remaining operation time of the ozonolysis step determined when the level has dropped to the level are satisfied. For this reason, even if the characteristic of the ozone sensor is defective, the ozone decomposition process can be terminated at a time when the ozone concentration becomes equal to or lower than the environmental standard value. In addition, it is possible to eliminate the possibility that the ozone decomposition operation is terminated while the high-concentration ozone remains. Thereby, the safety and reliability of the device can be further improved.

A feature of the invention according to claim 2 is that when the end permitting means satisfies all the end conditions based on the setting state of each end condition in the first to third end condition processing means, The ozonolysis process is allowed to end.

According to this configuration, the end of the ozonolysis step is when all of the first to third end conditions are satisfied,
Since the ozonolysis step is completed only after the judgment processing is performed for more condition processing, the safety of the ozone sterilizer at the time of completion can be further improved.

A third feature of the present invention is that a first ozone sensor which outputs a detection signal at a level corresponding to the ozone concentration in the sterilizing booth and can detect low-concentration ozone, By detecting whether or not the detection signal output from the first ozone sensor has reached a level corresponding to the safe low level during the operation of the ozonolysis step, the first ozone sensor is operated at the end of the ozonolysis step. First end condition processing means for setting that one condition is satisfied, and a required operation time of the ozone decomposition step determined based on an operation time of the ozone generation step by detecting an operation time of the ozone generation step A second end condition processing means for setting that the second condition relating to the end of the ozone is satisfied, and a step for performing the ozone decomposition step when both of the first and second end condition processing means are satisfied. In that and a end permission means for permitting completion.

With this configuration, the safety can be ensured even if the ozonolysis treatment is terminated by satisfying the first and second termination conditions. In other words, the ozonolysis operation does not end only depending on the detection value of the ozone sensor, but is used as the first ending condition. In addition, the operation time of the ozone decomposition process is assumed in advance based on the operation time required for the ozone generation process. Since it is possible, the safety can be similarly maintained by using this as the second condition and terminating the ozonolysis treatment when the first and second end conditions are satisfied. According to this configuration, it is possible to simplify a program necessary for determining the end of the ozonolysis step.

[0014] A feature of the invention according to claim 4 is that the termination permission means is configured to permit termination of the ozone decomposition step when the termination condition of the second termination condition means is satisfied. is there.

According to this configuration, the end time of the ozone decomposing step does not depend on the detection value of the ozone sensor, but the operation time of the ozone decomposing step is determined based on the operation time required for the ozone generating step. The termination of the operation of the disassembling process can be performed with a minimum number of condition determinations while safely terminating the operation, and the necessary device configuration can be minimized.

A fifth aspect of the present invention is characterized in that a sterilization booth, an ozone generator, and ozone from the ozone generator are mixed into air in the sterilization booth during sterilization to prevent ozone in the sterilization booth. An ozone generation step of increasing the concentration to a predetermined concentration for sterilization, a fumigation sterilization step of maintaining the sterilization environment generated in the ozone generation process for a predetermined period, and a safe ozone concentration of the air in the sterilization booth after completion of the sterilization. An ozone sterilization apparatus comprising a processing chamber in which an ozonolysis step of returning to a low level is sequentially performed, wherein an ozone sensor that outputs a detection signal at a level corresponding to the ozone concentration in the sterilization booth; A reference signal corresponding to a level higher than the ozone concentration is set, and the detection signal output from the ozone sensor during the operation of the ozone decomposition process is set. No. is in fact provided with a termination processing means for determining the remaining operating time to terminate the operation of the ozone decomposition step of the ozone decomposition step based on the fact that lowered to the reference signal corresponding level.

According to this configuration, the end time of the ozone decomposing step does not depend on the detection value of the ozone sensor. When the detection signal output from the high-concentration ozone sensor drops to a level corresponding to the reference signal, the ozone decomposing step is terminated. The remaining operation time is determined, and the termination of the operation in the ozonolysis process can be safely terminated, and the termination can be determined by the minimum number of condition determinations.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a schematic configuration diagram showing a first embodiment of an ozone sterilizing apparatus according to the present invention. The ozone sterilizing apparatus 1 includes a sterilizing booth 2 for performing a sterilizing process, and a main body device 3 for controlling the ozone concentration in the sterilizing booth 2. A processing chamber 4 is provided in the main unit 3, and air in the sterilization booth 2 is sent to the processing chamber 4 via a suction duct section 4A, and the atmosphere generated and processed in the processing chamber 4 is blown out of the blowing duct section 4.
It supplies to sterilization booth 2 via B. In the main body device 3, an ozone generator 5, an ultrasonic humidifier 6, a humidity detector 7, a power supply 8, a control device 9 for controlling each unit of the device, a cooling fan 10, and the like are further arranged. The main unit 3
The ozone concentration inside is detected by the monitoring ozone sensor 11,
Ozone leakage from the processing chamber 4 is monitored.

Inside the processing chamber 4, a suction passage 4C, an ozone decomposition chamber 4D, a blowing passage 4E, a communication passage 4
F is provided, and a blowing fan 4 i is provided in the blowing passage 4 </ b> E, and sends the atmosphere to the sterilization booth 2. A plate-shaped first damper 4J is provided between the suction passage 4C and the communication passage 4F, and a plate-shaped second damper 4J is also provided at a position facing the ozone decomposition chamber 4D and the suction duct 4A.
A damper 4K is provided, and each is rotatable by an actuator such as a motor.

The ultrasonic humidifier 6 comprises a humidifying tank 6A, a humidifier power supply 6B and an ultrasonic humidifier 6C, and fine particles of water atomized by the ultrasonic humidifier 6C are blown out through a humidifying hose 6D. It is sent into the passage 6E. On the other hand, a high voltage is supplied to the ozone generator 5 from a high-voltage power supply 5A, and ozone is generated using oxygen supplied from the outside via an oxygen hose 5B.
Through the outlet passage 4E.

The control device 9 controls each section for each of the following three steps. In the ozone generation step in preparation for starting the sterilization in the sterilization booth 2, the first damper 4J is opened and the second damper 4K is closed. In this state, the blower fan 4
By driving i, the air in the sterilizing booth 2 is blown out from the suction passage 4C through the communication passage 4F to the discharge passage 4E.
Sent to. Here, the flow path returning to the sterilization booth 2 is formed by mixing the humidified air and ozone from the ultrasonic humidifier 6, and the ozone concentration in the sterilization booth 2 is increased to a high concentration for sterilization.

In the fumigation sterilization step of performing sterilization for a specified time after the generation of ozone, the first and second dampers 4 are used.
J and 4K are opened and closed in the same manner as when ozone is generated, and air is circulated by the blower fan 4i. A detector 30A of the high-concentration ozone sensor 30 is provided near the inlet of the suction passage 4C. The control device 9 controls the high-concentration ozone sensor 3
The ozone generator 5 is turned on and off in response to the detection output of the high-concentration ozone sensor 30 so that the ozone concentration detected by 0 falls within a certain range.

After the sterilization treatment in the sterilization booth 2 is completed,
The control device 9 closes the first damper 4J and opens the second damper 4K to execute the ozone decomposition process. In this step, the air from the sterilization booth 2 is guided to the ozone decomposition chamber 4D, the ozone contained in the air is decomposed by the ozone decomposition catalyst 4G, and the air having a reduced ozone concentration is sent to the blowing passage 4E by the blowing fan 4i. The ozone concentration is returned to the sterilization booth 2 and returned to a state where the ozone concentration has been reduced to an environmental standard value that does not affect the human body. An ozone sensor 13 is provided in the ozone decomposition chamber 4D, and the ozone sensor 13 outputs a detection signal corresponding to the ozone concentration in the sterilization booth 2 to the control device 9. One sterilization process is performed by executing the above series of steps.

The ozone sensor 13 detects the ozone concentration of the air sent from the sterilizing booth 2 into the processing chamber 4 through the suction duct 4A. It is used to check whether or not the ozone concentration in the chamber has reached an environmental standard value (for example, less than 0.1 ppm) that does not affect the human body. In this embodiment, a semiconductor type ozone sensor whose resistance value changes according to the ozone concentration is used as the ozone sensor 13 suitable for such use. Reference numeral 7A denotes the suction passage 4
A humidity sensor for detecting the humidity of the air in C,
The humidity sensor 7A is connected to the humidity detector 7.

Next, the configuration of the main part of the control system of the ozone sterilizer 1 shown in FIG. 1 will be described with reference to FIG.
The control system of the ozone sterilizer 1 includes a microcomputer device 22 driven by a stabilized low voltage Vc supplied between the positive output terminal 21A and the negative output terminal 21B of the stabilized power supply circuit 21. One end of the semiconductor type ozone sensor 13 is connected to a grounded negative output terminal 21B, and the other end is connected via a resistor 23 to a positive output terminal 21A.
It is connected to the. Therefore, from the partial pressure connection point between the ozone sensor 13 and the resistor 23, a detection signal V of a voltage value corresponding to the ozone concentration of the air passing through the suction passage 4C.
S is output and input to the microcomputer device 22.

Before starting the sterilization process in the sterilization booth 2, the ozone concentration of the air in the sterilization booth 2 is a predetermined low level, for example, 0.1 ppm which is an environmental standard value (first standard value) which does not affect the human body. It is determined using the first reference value setting circuit whether or not the following is true (referred to as first detection determination processing). The first reference value setting circuit is configured such that the ozone sensor 13
A voltage generating circuit 24 outputs a first reference voltage value VL1 having a level equal to the detected voltage value VS1 output when the reference ozone concentration is detected. Voltage generation circuit 2
Reference numeral 4 denotes a resistance voltage dividing circuit formed by connecting resistors 24a and 24b in series. The voltage dividing connection point between the two resistors 24a and 24b is input to the microcomputer 22.

After a predetermined time has passed in the sterilization booth 2 after the ozone disinfection process (the fumigation sterilization process) that has been completed after the ozone sterilization process (fumigation sterilization process) has been completed, the ozone concentration detected by the high-concentration ozone sensor 30 decreases to a predetermined level. The determined time is determined using a second reference value setting circuit (referred to as a second detection determination process). Although the ozone concentration gradually decreases at the same time as the start of the ozonolysis step, the second reference value setting circuit determines that the detection signal VH of the high concentration ozone sensor 30 is equal to the second signal.
A voltage generation circuit 25 outputs a second reference voltage value VL2 at a level equal to the voltage value when a reference value (for example, 10 ppm) is detected. The voltage generating circuit 25 is configured as a resistor voltage dividing circuit formed by connecting resistors 25a and 25b in series. The voltage dividing connection point between the resistors 25a and 25b is input to the microcomputer device 22.

A resistor 27 and a light emitting diode 28 for alarm are connected between the output terminal 22A of the microcomputer device 22 and the positive output terminal 21A of the stabilized power supply circuit 21, which will be described later in detail. explain. The microcomputer 22 receives a detection signal VS from the ozone sensor 13, a detection signal VH from the high-concentration ozone sensor 30, a first reference voltage VL1, and a second reference voltage VL2. In addition, various input signals IS necessary for operation control of the ozone sterilization apparatus 1 are input, and an output signal OS is output from the microcomputer device 22 for operation control of the ozone sterilization apparatus 1.

The microcomputer device 22
Is provided with a timer 22B for measuring the time of the ozonolysis operation. Here, the high-concentration ozone sensor 30 detects high-concentration ozone (for example,
It is made mainly for measuring (00 ppm or more)
The ozone concentration (0.1 ppm) of the above-mentioned environmental standard cannot be accurately detected. However, the high-concentration ozone sensor 30 is different from the semiconductor-type ozone sensor 1 described above.
There is no fear that the detection characteristics will be degraded even when exposed to a high concentration of ozone as in 3.

Next, the operation control of the ozone sterilizer 1 by the control system shown in FIG. 2 will be described. 3 and 4 are flowcharts showing the contents of a control program stored in a memory (not shown) in the microcomputer device 22 of FIG. 2 and executed in the microcomputer device 22. FIGS. 3 and 4 show a basic process for determining the characteristics of the ozone sensor 13.

This control program is started and executed in response to turning on a power switch (not shown) of the ozone sterilizer 1. When the control program is started, first, an initialization process is performed in step SP1. At the start of the operation, the detection voltage value VS1 and the first reference voltage value VL1 output from the ozone sensor 13 at this time are fetched (step SP2). ), The detected voltage value VS1 is compared with the first reference voltage value VL1, and a level difference is detected (Step S).
P3). Next, a first detection determination process of the ozone sensor 13 is performed. The first detection determination process is performed by detecting the detection voltage value VS
Level difference between the first reference voltage value VL1 and the first reference voltage value VL1 | VS1-VL
It is determined whether 1 | is equal to or smaller than a predetermined value K (step SP4). In step SP4, this level difference | VS1-
When VL1 | is determined to be equal to or smaller than the predetermined value K, the determination result is YES, the normal operation is started, and the ozone generation step is started (step SP5). That is, the ozone concentration in the sterilization booth 2 is increased to a high level required for sterilization. Simultaneously with the start of the operation, the timer 22B starts counting the operation time TM1 of the ozone sterilization.

On the other hand, the first detection determination processing (step SP
If the result of the determination in 4) is NO, the ozone concentration in the processing chamber 4 has exceeded a predetermined low level which is assumed to have no effect on the human body before the start of operation, or the ozone sensor 13 means that the detection characteristics are abnormal. Therefore, in this case, the abnormal time processing is executed. In this abnormal state processing, first, an alarm signal AL is output (step SP20), thereby turning on the light emitting diode 28 (see FIG. 2) to notify the operator that the ozone concentration is high. Next, control for inhibiting the operation of the ozone sterilizer 1 is performed (step S).
P21) This abnormal time process ends. In addition, if a process for executing the ozonolysis operation for a predetermined time after step SP21 is added to the abnormal time process, the safety can be further improved.

Thereafter, in step SP6, the ozone concentration in the sterilization booth 2 is reduced to a specified concentration for sterilization (for example, 200p).
pm) is determined. If the specified concentration has been reached, the result of the determination in step SP6 is YES, and the next fumigation sterilization step is executed. This specified concentration is detected by the high concentration ozone sensor 30. The count value TM1 of the timer during the ozone generation step at the time when the concentration reaches the specified concentration is stored in the storage means of the microcomputer device 22 (step SP7). Thereafter, the fumigation sterilization process is continuously performed for a specified time while the ozone concentration in the sterilization booth 2 is maintained at a required high concentration.

When the specified time of the fumigation sterilization step has expired, the determination result of step SP8 is YES, and the ozone decomposition step is executed next. Simultaneously with the start of the ozonolysis step, the operation time TM2 of the ozonolysis step is set by the timer 22B.
Is started (step SP10). A register (identifier) FCN for determining the end of the ozone decomposition process
T is cleared to 0 (step SP11). The determination register is configured to be updated (set, reset) in the microcomputer device 22. Thereafter, the ozone decomposition process is continued until the ozone concentration in the sterilizing booth 2 falls to the environmental standard value. The end of the ozone decomposition process is determined when two of the following three conditions are satisfied. Have been. That is, the register FCN
T is used for determining whether these two conditions are satisfied.

1) Termination condition 1 (Ozone sensor 13)
Is detected by the ozone sensor 13 as to whether or not the ozone concentration in the sterilization booth 2 is equal to or less than the environmental reference value.
This is determined by executing P12. First, the ozone sensor 13
And the first reference voltage value VL1 are fetched and compared (step SP12A).
Here, since the first reference voltage value VL1 is set to a voltage value corresponding to the ozone concentration of the environmental reference value (for example, 0.1 ppm), the voltage value of the detection signal VS as a result of the comparison is equal to or less than the first reference voltage value VL1. If it is the value of step SP1
The determination result in 2A is YES, it is determined that the end condition 1 is satisfied, and bit 0 of the determination register FCNT is set (step SP12B). On the other hand, if the comparison result indicates that the detection signal VS is a value exceeding the first reference voltage value VL1 (the determination result in step SP12A is "mira", it is determined that the termination condition 1 is not satisfied, and the other termination conditions are determined. The process proceeds to the determination process of 2 and 3.

2) Termination condition 2 (when a predetermined time has passed in the ozone decomposition step corresponding to the time taken in the ozone generation step of the apparatus) The time taken in the ozone generation step, that is, from the start of the ozone generation step The time required until the fumigation sterilization step is executed is stored in the storage means as the count value TM1, and the time from the start of the ozone decomposition step is counted by the timer as the count value TM2. The end of the ozone decomposition process is determined by executing the second condition processing step SP13 based on these count values TM1 and TM2.

That is, the count value TM1 indicating the time spent in the ozone generation step, which is already stored as a fixed value in the storage means, is compared with the count value TM2 indicating the ozone decomposition step in the count state. When the time of the decomposition step exceeds a certain multiple of the time of the ozone generation step, that is, TM2 ≧ TM1 × N (where N is a predetermined coefficient)
Is satisfied and the determination result of step SP13A is YES, it is determined that the end condition 2 is satisfied, and the bit position of the determination register FCNT stored in the storage means is set (step SP13B). For example, when the coefficient N is set to 2 in advance, the end condition 2 is satisfied when the time of the ozone decomposition step becomes twice the time of the ozone generation step. On the other hand, if the above condition is not satisfied, the decision result in the step SP13A is NO,
It is determined that the termination condition 2 is not satisfied, and the process proceeds to another termination condition 3.

3) Termination condition 3 (when the time of the ozonolysis step after the detection value of the high-concentration ozone sensor has detected a predetermined value is equal to or longer than a predetermined time) The ozonolysis step is started. As a result, the ozone concentration in the sterilization booth 2 gradually decreases, and this ozone concentration is detected by the high-concentration ozone sensor 30. Based on the ozone concentration having decreased to the predetermined concentration, the end time of the ozone decomposition step is determined. The determination is made by executing the three-condition processing step SP14. First, the detection signal VH of the high-concentration ozone sensor 30 and the second reference voltage value VL2 are taken in (step SP).
14A). Next, the level of the detection signal VH is compared with the second reference voltage value VL2 (step SP14B).

Here, the second reference voltage value VL2 has a higher concentration (for example, 1 ppm) than the environmental reference value (for example, 0.1 ppm).
(0 ppm) corresponding to the second reference ozone concentration, the step SP1 is performed when the level of the detection signal VH drops to the second reference voltage value VL2 as a result of the comparison.
The decision result in the step 4B is YES, and the timer is started to count the count value M3 (step SP14C).
The count value M3 is set to a predetermined time T3.
Is determined (step SP14D).
If the specified time T3 has been exceeded, the determination result of step SP14D is YES, it is determined that the end condition 3 is satisfied, and bit 2 of the determination register FCNT is set (step SP14E). On the other hand, step SP14
B is NO (the level of the detection signal VH is the second
If the reference voltage value VL2 is exceeded, or if the result of the determination in step SP14D is NO (the specified time T3 is not satisfied), it is determined that the end condition 3 is not satisfied. .

When at least two of the above various termination conditions 1 to 3 are satisfied, the termination of the ozone decomposition step is permitted by the termination permission means provided in the microcomputer device 22. That is, first to third
Each bit of the determination register FCNT is set in the condition processing steps SP12, SP13, and SP14 (steps SP12B, SP13B, SP14).
In step E), when it is detected that the value of the determination register is 3, 5, or 6, the determination result of step SP15 is YE
In S, the end permission means permits the end of the ozonolysis step (step SP16). As described above, the configuration is such that the operation of the ozonolysis step is terminated when two or more of each of the first to third plurality of termination conditions are completed without terminating the ozonolysis step only with the detection value of the ozone sensor 13. By doing so, the ozone decomposition process can be safely terminated even if the detection characteristics of the ozone sensor 13 change (including deterioration and failure). Further, the ozone concentration in the sterilizing booth 2 at the end of the operation of the treatment ozonolysis step can be reliably reduced to the environmental standard value or less, and the safety to the human body and the reliability of the device can be further improved.

In FIG. 4, the first to third end condition processing steps SP12, SP13, and SP14 are described as time-series processing for the sake of convenience. The third end condition process may be given a predetermined priority to execute an interrupt process, or the first to third end condition processes may be executed simultaneously and in parallel. In the condition flag discrimination processing in step SP15, the above-mentioned 3
It is also possible to adopt a configuration in which the ozone decomposition step is stopped when all of the two termination conditions 1, 2, 3 are satisfied. On the other hand, when the ozone sensor 13 is exposed to high-concentration ozone in the ozone generation step and the fumigation sterilization step, the ozone sensor 13 may be configured not to be used for determining the end of the ozone decomposition step because the detection characteristics may be deteriorated. In this case, the first end condition processing step SP12 becomes unnecessary. Furthermore, for the same reason, the configuration may be such that the ozone decomposing step is terminated when either one of the second termination condition processing step SP13 and the third termination condition processing step SP14 is satisfied. In this case, the number of processes for determining the termination condition can be reduced while ensuring safety and reliability, and the device configuration required for the determination can be minimized.
In particular, when the ozonolysis process is determined to be completed only by the second ending condition processing step SP12, the high-concentration ozone sensor 30 and the determination process are not required, and the apparatus can be minimized.

FIG. 5 is a view showing the above-described series of sterilization treatment steps by the ozone sterilization apparatus 1 of the present invention. The horizontal axis in the figure is the operation time (hr) from the start of operation, and the vertical axis is the ozone concentration (p
pm). When the operation of the ozone sterilization apparatus 1 is started, first, an ozone generation step of increasing the ozone concentration in the sterilization booth 2 is executed. Then, after the ozone concentration reaches a predetermined specified concentration required for sterilization, a fumigation sterilization step is executed, and the ozone concentration in the sterilization booth 2 falls within a specified concentration range for a predetermined time. Is controlled as follows. After the expiration of the specified time of the fumigation sterilization step, the ozonolysis step is executed, and the ozone concentration in the sterilization booth 2 is reduced until it becomes equal to or less than the environmental standard value (0.1 ppm) as described above.

The true value of the ozone concentration is shown by the thick solid line in FIG. The dashed line in the figure indicates a detection value when the semiconductor-type ozone sensor 13 is in a state where the detection characteristics are deteriorated as a result of failure or exposure to high-concentration ozone, and a detection value different from the true value. Is output. The thin line in the figure is a detection value of the high-concentration ozone sensor 30. When the ozone concentration is high, the detection value is close to the true value, but the detected value is different from the true value as the concentration becomes lower. I understand. However, the high-concentration ozone sensor 30 can output a detection value closer to the true value than the detection value of the ozone sensor 13 whose characteristics have been deteriorated. As shown in the figure, when the detection characteristics of the ozone sensor 13 are deteriorated,
In the case where the end time of the ozone decomposition process is determined only by the detection value of No. 3, the ozone sensor 1
Even if 3 outputs a detection value equivalent to the environmental standard value, the sterilization booth 2
This means that about 30 ppm of ozone remains in the inside.

Here, when examining the change state of the ozone concentration, the time required for the ozone decomposition step is about twice (about one hour and thirty minutes) the time required for the ozone generation step (about 45 minutes). It turns out there is. Therefore, in the present invention, by setting the value of the coefficient N to 2 in the second end condition process, when the time required for the ozone decomposition process reaches twice the time required for the ozone generation process, Can be safely terminated. further,
In the third termination condition, the timer 22B starts counting when the detection value of the high-concentration ozone sensor 30 reaches the second reference value VL2 (10 ppm), and decomposes ozone when the count value TM3 reaches the specified time. Since the process is completed, the count value TM3 is set as a time TM3 corresponding to the time when the ozone concentration reaches the environmental standard value (period from time t1 to time t3), so that the ozone decomposition process can be performed safely. Can be terminated.

Then, either one of the second and third end condition processes, or the first end condition process based on the detection value of the ozone sensor 13 detecting the environmental reference value, for a total of three end condition processes If the configuration is such that the ozonolysis operation is terminated when the two termination conditions of the processing are met, the ozone concentration at the end of the ozonolysis operation can be reduced to a safe concentration equal to or lower than the environmental standard value, and safety and reliability can be reduced. Ability can be improved.

[0046]

According to the first aspect of the present invention, in the ozone decomposing step executed after the end of the sterilization treatment of the ozone sterilizer, the first end condition is set when the detection value of the ozone sensor drops to the environmental reference value. The second condition in which the operation time of the ozonolysis step is determined based on the operation time of the generation step, and the remainder of the ozonolysis step when the detection signal output from the high-concentration ozone sensor drops to a level corresponding to the second reference signal. In this configuration, a total of three end conditions of the third condition for determining the operation time are set and judged by the first to third end condition processing means, and the end permission means determines two or more of these. Since the operation of the ozone decomposition process is terminated when the conditions are satisfied, the ozone concentration becomes lower than the environmental standard value even when the characteristics of the ozone sensor are defective. In will be able to terminate the ozone decomposition step, inconvenience and the ozonolysis operation can not be completed, ozonolysis continuous running of the ozone residual predetermined concentration will be able to eliminate the possibility of such ends. As a result, it is possible to secure an operation with higher safety than before, while ensuring environmental safety.

According to the second aspect of the present invention, the termination permission means terminates the ozonolysis step when all of the first to third termination conditions are satisfied. Since the ozonolysis step is completed only after the treatment, the safety of the ozone sterilizer at the end can be further improved.

According to the third aspect of the present invention, the termination permitting means terminates the ozonolysis treatment when the first and second termination conditions are satisfied. Safety can be ensured. That is, the ozonolysis operation is not completed only depending on the detection value of the ozone sensor, but the ozonolysis operation can be assumed in advance based on the operation time required for the ozone generation process in addition to the first ending condition. Therefore, this is set as the second condition, and the ozonolysis treatment is ended when these two first and second end conditions are satisfied. Therefore, it is possible to determine the end of the ozonolysis process while maintaining safety. Necessary program configuration can be simplified.

According to the fourth aspect of the present invention, the end time of the ozone decomposition step is determined based on the operation time required for the ozone generation step. It is performed without depending on the detection value, and even if the detection characteristics of the ozone sensor deteriorate after being exposed to high concentration ozone, the operation of the ozone decomposition process can be safely ended and the end judgment can be made with the minimum number of condition judgments, The required device configuration can also be minimized.

According to the fifth aspect of the invention, in the ozonolysis step, the remaining operation time is determined when the detection signal output from the high-concentration ozone sensor drops to a level corresponding to the reference signal. It is performed without depending on the detection value of the ozone sensor. Even if the detection characteristics of the ozone sensor deteriorate after exposure to high-concentration ozone, the operation of the ozone decomposition process is safely terminated and the termination judgment is made with the minimum number of conditions. Will be able to do it.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing an ozone sterilizing apparatus according to a first embodiment of the present invention.

FIG. 2 is a circuit diagram showing a control system of the ozone sterilizing apparatus of FIG.

FIG. 3 is a flowchart (part 1) illustrating an operation detection process of an ozone sensor performed by the microcomputer device shown in FIG. 2;

FIG. 4 is a flowchart (part 2) illustrating an operation detection process of the ozone sensor executed by the microcomputer device shown in FIG. 2;

FIG. 5 is a view showing an ozone concentration that changes in a series of sterilization treatment steps by the ozone sterilization apparatus of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ozone sterilization apparatus 2 Sterilization booth 5 Processing chamber 13 Ozone sensor 22 Microcomputer device 28 Light emitting diode 30 High concentration ozone sensor 30A Detector VS, VH detection signal VL1 First reference voltage value VL2 Second reference voltage value AL alarm signal

Claims (5)

[Claims] 1. A sterilization booth, an ozone generator, and ozone which increases ozone concentration in the sterilization booth to a predetermined concentration for sterilization by mixing ozone from the ozone generator into air in the sterilization booth during sterilization. The generation step, the fumigation sterilization step of maintaining the sterilizing environment generated in the ozone generation step for a predetermined period, and the ozone decomposition step of returning the ozone concentration of the air in the sterilization booth to a safe low level after completion of the sterilization are sequentially switched. An ozone sterilizer having a processing chamber to be executed, wherein the first ozone sensor outputs a detection signal at a level corresponding to the ozone concentration in the sterilization booth and is capable of detecting low-concentration ozone; It outputs a detection signal at a level corresponding to the ozone concentration in the sterilization booth, and detects ozone at a higher concentration than the first ozone sensor. A second ozone sensor, and detecting whether or not a detection signal output from the first ozone sensor during the operation of the ozone decomposition step has reached a level corresponding to the safe low level. First ending condition processing means for setting that a first condition for ending the operation of the process is satisfied, and detecting the operation time of the ozone generation process and detecting the ozone determined based on the operation time of the ozone generation process Second end condition processing means for setting that the second condition for ending the required operation time of the decomposition step is satisfied; and a detection signal output from the high-concentration ozone sensor during operation of the ozonolysis step. The remaining operation time of the ozonolysis process is determined based on the drop to a level corresponding to a concentration slightly higher than the safe low level, and the operation of the ozonolysis process is terminated. Third end condition processing means for setting that the third condition is satisfied, and at least two or more end conditions are satisfied based on the setting state of each end condition in the first to third end condition processing means. And an end permitting means for permitting an end of the ozonolysis step when the ozone disinfection step is ended. And a termination permission unit configured to permit termination of the ozonolysis step when all termination conditions are satisfied based on a setting state of each termination condition in the first to third termination condition processing units. The ozone sterilizer according to claim 1, wherein 3. A sterilization booth, an ozone generator, and ozone for mixing ozone from the ozone generator into air in the sterilization booth during sterilization to increase the ozone concentration in the sterilization booth to a predetermined concentration for sterilization. The generation step, the fumigation sterilization step of maintaining the sterilizing environment generated in the ozone generation step for a predetermined period, and the ozone decomposition step of returning the ozone concentration of the air in the sterilization booth to a safe low level after completion of the sterilization are sequentially switched. An ozone sterilizer having a processing chamber to be executed, wherein the first ozone sensor outputs a detection signal at a level corresponding to the ozone concentration in the sterilization booth and is capable of detecting low-concentration ozone; Detecting whether or not the detection signal output from the first ozone sensor during the operation of the ozonolysis step has reached a level corresponding to the safe low level; With this, a first termination condition processing means for setting that the first condition relating to the end of the operation of the ozone decomposition step is satisfied, and an operation time of the ozone generation step is detected and based on the operation time of the ozone generation step. A second ending condition processing means for setting that the second condition relating to the end of the required operation time of the determined ozonolysis step is satisfied; and an ending condition of the first and second ending condition processing means. An ozone sterilizing apparatus, comprising: an end permitting means for permitting the end of the ozonolysis step when both are satisfied. 4. A sterilization booth, an ozone generator, and ozone for increasing ozone concentration in the sterilization booth to a predetermined concentration for sterilization by mixing ozone from the ozone generator into air in the sterilization booth during sterilization. The generation step, the fumigation sterilization step of maintaining the sterilizing environment generated in the ozone generation step for a predetermined period, and the ozone decomposition step of returning the ozone concentration of the air in the sterilization booth to a safe low level after completion of the sterilization are sequentially switched. An ozone sterilizer having a processing chamber to be executed, wherein the first ozone sensor outputs a detection signal at a level corresponding to the ozone concentration in the sterilization booth and is capable of detecting low-concentration ozone; The operation time of the ozone generation step is detected, and the required operation time of the ozone decomposition step, which is determined based on the operation time of the ozone generation step, ends. Second end condition processing means for setting that the condition is satisfied; and end permission means for permitting the end of the ozone decomposition step when the end condition of the second end condition processing means is satisfied. An ozone sterilizer characterized by the following. 5. A sterilization booth, an ozone generator, and ozone for increasing ozone concentration in the sterilization booth to a predetermined concentration for sterilization by mixing ozone from the ozone generator into air in the sterilization booth during sterilization. The generation step, the fumigation sterilization step of maintaining the sterilizing environment generated in the ozone generation step for a predetermined period, and the ozone decomposition step of returning the ozone concentration of the air in the sterilization booth to a safe low level after completion of the sterilization are sequentially switched. An ozone sterilization apparatus comprising a processing chamber to be executed, an ozone sensor that outputs a detection signal at a level corresponding to the ozone concentration in the sterilization booth, and a level higher than the safe low-level ozone concentration. A reference signal to be set is set, and the detection signal output from the ozone sensor during the operation of the ozone decomposition process is reduced to a level corresponding to the reference signal. Ozone disinfection apparatus characterized by comprising: a termination processing means for terminating the operation of the ozone decomposition step to determine the remaining operating time of the ozone decomposition step, based on the beat was a.