JPS5865166A - Gas pasturization apparatus - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a gas sterilizer that sterilizes medical equipment 11 materials, etc. using a toxic sterilizing gas such as ethylene oxide or formaldehyde, which is usually supplied in a cylinder under pressure. It was invented with the aim of providing a gas sterilizer that can perform sterilization operations when the residual sterilization gas is reduced.

As the structure and outline of the gas sterilizer is shown in the first figure, the inside of a can body 2 having a sealed lid 1 is connected to a gas source 5 through an air supply pipe 4 provided with an air supply valve 3, and an exhaust valve 6 is connected to the gas source 5. and exhaust pump 7
The exhaust pipe 8, which is provided with a

To perform gas sterilization, close the air supply valve 3 and open the tJI air valve 6.
Open the exhaust pump 9 times, exhaust the inside of the can body 2 to a vacuum state, then close the exhaust valve 6, stop the exhaust pump 7, open the air supply valve 3, and remove the gas from the gas source 5. Pressure sterilizing gas fi: put 016 people in the cloth body 2, then close the air supply valve 3 and set it, release it between JI> (in the case of ethylene oxide, 3n interval), set the sterile gas sealed in the can body 2 This is done by infiltrating the objects to be sterilized inside the can.

After sterilization is completed, open the exhaust valve 6 and operate the exhaust pump 7.
While filtered clean air is allowed to flow into the can body 2 from a pipe (not shown), the sterilizing gas inside the can body is discharged from the exhaust pipe 8, the lid is closed and the object to be sterilized is taken out.

In the gas sterilizer used in this way, a poisonous gas which is pressurized and filled into a cylinder is used as the gas source 5. usually,
Ethylene oxide is often used, but in the case of this gas,
Nitrogen is mixed in to moderate the toxicity, so when the amount of gas in the cylinder decreases, the gas concentration will decrease, so sterilization work is usually done by checking the remaining gas amount and changing the sterilization time. being done. For example, a bong with -R of 15 to 9 is filled with about z(rkq) of ethylene oxide, so if you check the change in the weight of the bong, you can find out how much gas is left.

When the remaining amount of gas reaches 10 to 20%, the action of ethylene oxide becomes unstable, and even if sterilization is carried out for a set time, the sterilization effect may not be sufficient in some rinses.

Also, since the pressure when filling a cylinder with gas is around 5~1, you can measure the gas pressure to know when the remaining amount of gas is low, but if the gas pressure is 3~2 yen. The action of the gas becomes unstable.

Note that the action of the sterilizing gas is significantly affected by its humidity, so the sterilization time should be changed depending on the humidity.

The present invention provides a gas sterilizer that detects the pressure of sterilizing gas inside a can and performs sterilization for a time that matches the current gas condition.

Next, an embodiment for ethylene oxide in which the sterilization time is changed by detecting the pressure of the sterilization gas will be described with reference to the flowchart of FIG. 2 showing the progress of the work.

Once the inside of the can 2 containing the objects to be sterilized has been evacuated to a vacuum state as described above, the start button 0 is pressed to start the sterilization process.

First, first process] In the IE, the air supply valve 3 is opened, and sterilizing gas enters the can body 2.

Next, in a second process 12, the pressure P inside the can is detected.

This pressure P is compared in the next first judgment 13 to see if it is equal to the set pressure P during sterilization (for example 17~),
If they are equal, the air supply valve 3 is closed in the third process 14 and the air supply valve 3 is closed. The gas supply is +)- and the process moves to the next second judgment 15.

When it is determined in the first determination 11 that the pressure P inside the can does not reach the set pressure R+, in the next second determination 15, p and -p are 0.
．． 3 or more]. When p, , -p is larger than 03~, that is, when the gas pressure is insufficient for sterilization, a signal is sent to the first processing 11 to continue supplying air to increase the internal pressure, and p, -p is not larger than 0.3 yen, that is, when the gas pressure inside the can is low but still sufficient to sterilize, the following fifth judgment 16 indicates that P
,, - Determine whether P is greater than 02~ or 100.

When this differential pressure is greater than 0.2, the fourth process is performed to extend the set time by 1.5 times by 3 hours. That is, when sterilization is possible even though the gas pressure is low, the timer that controls the sterilization time is adjusted to extend the sterilization time.

If P,, -P is not larger than 02~, the fourth judgment 1
P by 8. - It is determined whether Pl is larger than 0.1 or white, and if it is larger, the sterilization time is 1.
A process of increasing the time by 25 times, that is, a slightly longer time than above is performed. .

If p and -p are not greater than O1~, it is assumed that the sterilization ability is sufficient, and sterilization is performed for 3 hours at an extension multiple of 1 in the sixth process 20.

There is sufficient sterilization gas pressure, and in the first judgment 13, p
If it is determined that =p, , the second to fourth determinations are passed and sterilization for 3 hours is still performed in the sixth process 20.

When the sterilization for each time is completed in each process 17, 19, and 20, the end of the sterilization time r is judged in the fifth judgment 21, a table tJ<22 indicating the completion of sterilization is displayed, and the process for removing the object to be sterilized is performed. Transition.

In addition, if the gas cylinder is slightly depleted or the gas pressure decreases, the worker may decide separately whether to replace the cylinder with a new one, but the computer in 1. Therefore, the fifth judgment 2, as shown by the chain line in Figure 2, receives a signal indicating the weight or gas pressure of the cylinder and determines whether the cylinder can be used or whether it should be replaced.
3 between the first process 11 and the second process 12, when the start button 10 is pressed to start sterilization, if the gas source is in an inappropriate state, the cylinder will be replaced automatically. A display 24 is displayed, and if the gas source is normal, subsequent processing can be performed to ensure sterilization.

In the example 1-1, sterilization was performed by increasing and decreasing the pressure of the cylinder.
This is an example of adjusting l, and when the gas elbow in the cylinder decreases, it is possible to use it or not, and even if it is usable, whether or not the sterilization time should be extended, and if so, Since the system automatically determines how much to extend the set time and performs sterilization, reliable sterilization can be achieved without the operator having to consider the condition of the gas source. It's Moa. Therefore, the reliability of sterilization can be significantly increased compared to the conventional gas sterilization which is performed simply by setting a time.

In addition, in the case of a sterilizing gas such as ethylene oxide whose sterilizing ability changes depending on the temperature, the sterilization time can be changed depending on the temperature in the same manner as the gas pressure described above.

Figure 3 shows the standard temperature T. A flowchart for an example of an apparatus in which the sterilization time is changed according to the degree of difference between the temperature T of the sterilization gas and the temperature T of the sterilization gas actually flowing into the can is shown below, taking the case of ethylene oxide as an example.

A temperature sensor (not shown) is installed inside the can body 2 to detect its temperature.

Assuming that the process starts from the point where the pressure reduction process in the can body 2 has been completed, pressing the start button 10 and opening the air supply valve 3 in the first process 11 is the same as in the case of pressure. Subsequently, the actual temperature T inside the can body is measured in a third determination process 25, and it is determined in a seventh determination 26 whether or not 'r''To is reached.
= T.

If so, the third process 14 closes the air supply valve 3 and starts sterilization.

If it is not T STo, the eighth judgment 27 is T, -'I'
It is determined whether the temperature is higher than 15℃, and if it is, continue to supply sterilizing gas, and if the dog does not listen, the ninth judgment 2 is made.
T by 8. - It is determined whether or not T is greater than 10"C. If it is greater than 10"C, the sterilization time is extended by 151 times in the fourth process 17, and if it is not greater than 10℃, the first judgment 2 -9 determines whether T6 T>5°C or old. If it is large, the sterilization time is extended by 1.25 times in the fifth process 19, and if it is not large, the sterilization time is extended by 1.25 times in the sixth process 20 and sterilization is performed for 3 hours. The completion of sterilization is performed at the ninth judgment 28. When the sterilization is completed, a display 31 is displayed, and if the sterilization is not completed, the sterilization operation is repeated from the beginning.

In this way, when the sterilizing ability of the gas is reduced during flushing, the sterilization time is extended according to the degree of deterioration, so that sufficient gas sterilization can be achieved as a result.

Further, by using both the sterilization time change based on the gas temperature and the above-mentioned sterilization time change based on the gas pressure, the time can be extended by combining the time extension due to the temperature difference and the time extension due to the pressure difference. For example, the gas pressure is 0.15 to 1.
25) When the temperature is 12℃ (extension multiple 15), set the timer that controls the sterilization time to 3X1.2.
As 5X1.5, sterilization time can be automatically adjusted by taking pressure and temperature into account.

As described above, the present invention provides a gas sterilizer that can perform sterilization appropriate to the situation even when the remaining amount of sterilization gas is low, and enables reliable gas sterilization by tit operation. It is effective as a device for achieving practical results.

[Brief explanation of the drawing]

Figure 1 is a schematic diagram showing the general flow of the gas sterilizer, Figure 2 is a flowchart showing how the sterilization time is changed in response to changes in sterilization gas pressure, and Figure 3 is the temperature of the sterilization gas. A similar flowchart for responding to changes. 1: Airtight lid, 2: Can body, 3: Air supply valve, 4: Air supply pipe, 5:
Gas source, 6: Exhaust valve, 7: Exhaust pump, 8: Exhaust pipe, 9
: Exhaust treatment device, 10: Start button, 11: First treatment,
12: Second processing, 13: First judgment, 14: Third processing, 1
5: Second judgment, 16: Third judgment, 17: Fourth processing, 18
: Fourth judgment, 19: Fifth processing, 20: Sixth processing, 21:
Fifth judgment, 22: Display, 23: Sixth judgment, 24: Display,
25: Seventh processing, 26: Seventh judgment, 27: Eighth judgment, 2
8: Ninth Judgment, 29: Disciple Judgment, 30: Disciple - Judgment, 3
】:display. Patent applicant: Chiyoda Manufacturing Co., Ltd. Figure 1

Claims (1)

[Claims] A gas sterilizer that detects the pressure of the sterilizing gas supplied to the can body and extends the sterilization time if the sterilizing gas pressure is lower than the set pressure at which sterilization should be performed.