JP3747303B2 - Gas measuring device in sealed space - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention can be used for gas measurement in a sealed space such as a sealed container or a sealed chamber, such as humidity measurement in an ethylene oxide sterilizer.
[0002]
[Prior art]
When an ethylene oxide sterilizer is described as an example, the presence of moisture is necessary for ethylene oxide to exert a sterilizing action. The water content is suitably 25 to 50% with respect to ethylene oxide, and when it reaches 80%, the sterilization effect cannot be obtained. Therefore, at the time of sterilization, first, the air in the sterilizer is exhausted to a vacuum state, and then sprayed water or water vapor is supplied to increase the humidity in the vessel, and the humidity in the vessel is measured to make the humidity appropriate. At that time, humidification was stopped and ethylene oxide gas was supplied to adjust the humidity to 25 to 50% with respect to ethylene oxide.
[0003]
In order to measure the humidity inside the sterilizer, conventionally, a sensor sensing section in which a humidity measurement bridge circuit is embedded in a synthetic resin is exposed inside the container, and received from the sensor measuring section provided outside the container. A voltage was applied to the sensitive part, and voltage fluctuations due to some humidity were measured to determine whether the internal humidity was appropriate.
[0004]
Since this sensitive part is always installed in the container, when ethylene oxide is fed and sterilization is started, it is inevitable that ethylene oxide adheres to the sensitive part and corrodes it, deteriorating the performance. . In order to remove the attached ethylene oxide, the sensitive part may be heated, but this is dangerous because ethylene oxide is flammable. If the sensor is removed and the heating operation is performed in a safe place, the danger can be avoided, but the operation is troublesome.
[0005]
Therefore, in order to avoid such deterioration of the sensing part, a structure as shown in FIG. 3 has been considered. FIG. 3 is a longitudinal sectional view of a part of the wall of the ethylene oxide sterilizer.
[0006]
In this apparatus, a sensor sensing part 4 is attached to a conduit 2 attached to a wall 1a of a sterilizer 1 and a heat insulation jacket 6 surrounding the wall 1a through a valve 3, and the valve 3 is opened only at the time of measurement. The moisture sent into the chamber is passed through the sensing part 4 to know the humidity inside the chamber.
[0007]
When the humidity measurement is finished, the valve 3 is closed to shut off the sensing part 4 from the inside of the sterilizer. Next, even if ethylene oxide is fed, since the sensitive part does not come into contact with ethylene oxide, the performance of the sensitive part 4 does not deteriorate due to this gas.
[0008]
[Problems to be solved by the invention]
When the humidity measuring device is configured as described above, the moisture in the sterilizer 1 passes through the conduit 2 and the valve 3 to reach the sensor sensing part 4, so that the moisture that has entered the front and remains in this passage can be removed. As a result, the measurement of new humidity in the vessel is hindered and the measurement becomes inaccurate. It was difficult to immediately know the rapidly changing humidity while introducing moisture into the sterilizer.
[0009]
Even in the gas measurement in another sealed space described as an example in the ethylene oxide sterilizer, it is inevitable that a large measurement error is caused in the configuration shown in FIG.
[0010]
[Means for Solving the Problems]
In the measuring device of the present invention, the sensor sensing part is mounted in the end of a tubular rod inserted into the sealed space, and a valve is provided at the end of the rod, and the sensor is sensitive to the side of the rod close to the valve. A window is opened at a certain position, and as the rod is supported by the base mounted on the wall of the sealed space and vertically moves, the valve opens and closes the through hole of the base, and the window provided on the rod is sealed. This problem is solved by configuring a gas measuring device in a sealed space so as to be exposed in the space or blocked from the sealed space.
[0011]
[Action]
When the rod enters the sealed space and the valve opens, gas enters the rod through the window on the side of the rod and contacts the sensing part, and the gas state can be sensed and detected by the measuring part. . Since the sensing part is in direct contact with the gas in the sealed space, it is possible to quickly and accurately measure the gas state change. When the measurement is not performed, the valve is closed to shut off the sensitive part and the gas, so that the time during which the sensitive part is exposed to the gas is significantly reduced.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a longitudinal sectional view of a portion of a sterilizer wall schematically illustrating a first embodiment of the present invention for an ethylene oxide sterilizer.
[0013]
A wall 1a of the sterilizer 1 that forms a sealed space is surrounded by a jacket 6 that is filled with warm water for heat retention. Holes 7 and 8 are bored in the vessel wall 1a and the jacket 6, and a base 9 is fitted into the holes 7 and 8, and the vessel wall 1a and the jacket 6 are hermetically welded. The base 9 is formed with a large diameter portion 13 constituting a valve seat on both ends of a central hole 11 through which a tubular rod 10 is inserted, and a sealing material 12 is fitted on the sterilizer 1 side. A large diameter portion 15 into which the bellows 14 is placed is formed. The bellows 14 has the closed end 14a on the sterilizer 1 side adhered to the rod 10 in an airtight manner, and the open end 14b is airtightly adhered to the end plate 16 to block the inside and outside of the sterilizer 1 from each other. An elastic buffer plate 17 is attached to the outside of the end plate 16. One end of a ring-shaped connecting member 18 is attached to the outer end portion of the rod 10, and the other end of the connecting member 18 is coupled to the drive shaft 19 a of the actuator 19. A valve 20 of a shape corresponding to the sealing material 12 is attached to the end of the sterilizer on the rod 10, and a window 21 is opened on the side of the rod 10 exposed in the sterilizer 1 when the valve 20 is opened. The sensor 22a of the humidity sensor is attached to the inside thereof, and the measuring part 22b connected thereto is attached to the outer end of the rod 10. A bearing 23 guides the longitudinal movement of the rod 10. Instead of fitting the sealing material 12 to the large-diameter portion 13 as a valve seat, a sealing material is attached to the valve 20 and the large-diameter portion 13 is also effective as a valve seat corresponding to this.
[0014]
Since it is configured as described above, when the inside of the sterilizer is evacuated and then moisture is fed into the chamber, the actuator 19 pushes the rod 10 to the sterilizer 1 side via the connecting member 18. 1, the valve 20 is separated from the sealing material 12 and the window 21 on the side surface of the rod is exposed in the sterilizer. Leakage of moisture through the hole 11 and the outside air reaching the sensing part through the hole 11 when the inside of the chamber is evacuated are prevented by the bellows 14. The appropriate amount of protrusion of the rod 10 in the sterilizer is regulated by the connection member 18 coming into contact with the buffer plate 17. As a result, the moisture in the sterilizer 1 enters the rod through the window 21 and comes into contact with the sensing part 22a, and the humidity is taken out from the measuring part 22b as an electrical signal.
[0015]
When the actuator 19 is driven in the reverse direction and the rod 10 is pulled out from the sterilizer 1, the valve 20 abuts against the sealing material 12 to prevent moisture from flowing out to the base 9, and the sensing part 22a is moisture in the sterilizer. Humidity measurement is terminated when it is no longer touched.
[0016]
FIG. 2 is a longitudinal side view schematically showing a second embodiment similar to FIG. The same parts as those in FIG. 1 are denoted by the same reference numerals and the description thereof will be omitted.
[0017]
A piston 25 is coupled to the rod 10 outside the buffer plate 17, and a cylinder 26 into which the piston 25 is fitted is attached to the end plate 16 with the buffer plate 17 interposed therebetween. Reference numerals 27, 28 and 29 denote buffer plates 17, pistons 25 , sealing materials attached to end plates of the cylinder 26, and 30 and 31 denote pressure fluid supply / discharge pipes to the cylinder 26. Reference numeral 32 denotes a pipe for detecting leakage from the sealing material 27 and is connected to the leakage detector.
[0018]
When pressurized fluid such as compressed air is supplied from the pressurized fluid supply / discharge pipe 30 into the cylinder 26 and the piston 25 is pushed toward the sterilizer to cause the rod 10 to move vertically, the valve 20 opens, and the inside of the sterilizer 1 passes through the window 21 . Humidity can be measured.
[0019]
When the pressure fluid is introduced from the pressure fluid supply / discharge pipe 31 and the valve 20 is closed, the sensor 22a and the inside of the sterilizer can be shut off to stop the measurement. The piston 25 and the cylinder 26 are used in place of the actuator 19 and the connecting member 18 in the first example, and the bellows are not used.
[0020]
The ethylene oxide sterilizer humidity measuring device illustrated and described here is capable of adsorbing ethylene oxide since the sensitive part does not contact ethylene oxide after the humidity in the sterilizer is first measured. Absent. Therefore, it is not necessary to perform the degassing operation by heating the sensing part, and the troublesome work and danger associated with the degassing process can be avoided.
[0021]
The present invention is not limited to the ethylene oxide sterilizers exemplified above, but is used for devices that measure the temperature, humidity, pressure in a sealed space such as other sealed containers and sealed chambers and know the state of chemical change. It can be used as a measuring device that can quickly and accurately know the state change of the sensor and protect the sensor.
[0022]
【The invention's effect】
(1) The sensor sensitive part is brought into contact with the gas to be measured only at the time of measurement. After the measurement is completed, the sensitive part and the gas are shut off, so the contact time between the sensitive part and the gas can be significantly shortened. . When the sensitive part is corroded by gas, the deterioration of the sensitive part can be reduced.
[0023]
(2) Like an ethylene oxide sterilizer, when moisture is first fed into the chamber and its humidity is measured and then ethylene oxide is fed, the sensor does not come into contact with ethylene oxide. The sensor does not deteriorate due to ethylene oxide. There is no need to heat the sensitive part to degas.
[0024]
(3) Since the sensor's sensitive part is inserted into the target gas for direct measurement, rapid and accurate measurement is possible.
[Brief description of the drawings]
FIG. 1 is a partial longitudinal sectional view of a wall of an ethylene oxide sterilizer schematically shown as a first example of an embodiment of the present invention.
FIG. 2 is a similar longitudinal sectional view showing a second example.
FIG. 3 is a partial longitudinal sectional view of a wall of a humidity measuring device of an ethylene oxide sterilizer schematically shown as a conventional example.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Sterilizer 1a Instrument wall 2 Conduit 3 Valve 4 Sensitive part 6 Jacket 7, 8 hole 9 Base body 10 Rod 11 Hole 12 Sealing material 13 Large diameter part 14 Bellows 14a Closed end 14b Open end 15 Large diameter part 16 End plate 17 Buffer Plate 18 Connecting member 19 Actuator 19a Drive shaft 20 Valve 21 Window 22 Humidity sensor 22a Sensitive part 22b Measuring part 23 Bearing 25 Piston 26 Cylinder 27, 28, 29 Sealing material 30, 31 Pressure fluid supply / discharge pipe 32 Pipe

Claims (1)

A base is attached to the wall surrounding the sealed space in an airtight manner, and a tubular rod in which the end of the sealed space is placed in this space is supported in a vertically movable manner, and the end of the rod in the sealed space is formed on the base. A valve to be attached to and detached from the valve seat is attached, a window is opened on the side of the rod close to the valve, a sensor sensing part is provided in the rod at the position of the window, and this receiving part is located at the end opposite to the sealed space of the rod. A sealed space provided with a sensor that is connected to the sensor, and that has a drive mechanism that vertically moves the rod to attach and detach the valve to the base so that the window of the rod is exposed in the sealed space or is shut off from this space. Inside gas measuring device.

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