JP4829134B2 - Sterilizer - Google Patents

Description

  The present invention relates to a sterilizer used for sterilizing an object to be sterilized by placing the object to be sterilized such as medical equipment in an atmosphere of sterilization gas such as ethylene oxide gas (EOG).

  This type of sterilizer accommodates materials to be sterilized such as medical equipment to be sterilized in a sterilization chamber that can be completely sealed, and after the sterilization chamber is sealed, the inside of the sterilization chamber is evacuated by a vacuum pump. The sterilization chamber is introduced into the sterilization chamber, and the sterilization chamber is kept sealed in the sterilization chamber, and the sterilization chamber is kept at a predetermined temperature, for example, 40 ° C. to 60 ° C. for a predetermined time, for example, 3 hours. It is an instrument that performs sterilization of an object to be sterilized by maintaining for -6 hours.

For introduction of the sterilization gas into the sterilization chamber, for example, a sealed cartridge can filled with ethylene oxide (95 wt%, diluent CO ₂ 5 wt%) is used, and the cartridge can is perforated. Then, the sterilization gas is sent from the cartridge can into the sterilization chamber by breaking the container.

In such a sterilizer, it is necessary to introduce moisture into the sterilization chamber in order to obtain a sufficient sterilization effect, and it is necessary to maintain the sterilization chamber during sterilization treatment at 30 to 40% rh. For this reason, conventionally, in order to supply water to the sterilization chamber, a water supply tank containing water and a sterilization chamber are connected by a water supply pipe provided with a solenoid valve in the middle, and the above-mentioned solenoid valve is connected with the sterilization chamber decompressed. A predetermined amount of water was to be introduced into the sterilization chamber by opening the valve for a certain period of time (Patent Document 1 below).
JP 2002-224199 A JP 11-076385

  However, in the above conventional sterilizer, water does not exist in the water supply pipe in the first sterilization operation, so even if the solenoid valve is opened, while the water is first sucked from the water supply bottle into the water supply pipe, Since water is not introduced into the sterilization chamber, the amount of water introduced into the sterilization chamber is less than the expected amount even if the solenoid valve is opened for a certain period of time. In the second and subsequent sterilization operations, since the water supply pipe is filled with water, the water in the water supply pipe is introduced into the sterilization chamber as soon as the solenoid valve is opened. More water will be introduced than when. In addition, since water is supplied using the reduced pressure in the sterilization chamber, the amount of water sucked up varies depending on the remaining amount of water in the water supply bottle, resulting in variations in the amount of water supply. Also, when the degree of vacuum in the sterilization chamber changes, the amount of water sucked from the water supply bottle also changes, so depending on the condition of the material to be sterilized inserted in the sterilization chamber, the depressurization time and the degree of vacuum also vary. Variations will occur. If the amount of water supply is less than expected, sterilization may not be performed sufficiently, resulting in poor sterilization. If the amount of water supply exceeds the assumption, sterilization gas (EOG) reacts with water to produce a reaction product (ethylene glycol). In addition, there is a possibility of adversely affecting the article to be sterilized itself.

  This invention is made | formed in view of such a situation, and it aims at provision of the sterilizer which can always supply a fixed quantity of water to a sterilization chamber.

In order to achieve the above object, the sterilizer of the present invention includes a sterilization chamber in which an object to be sterilized is stored,
A vacuum pump for depressurizing the sterilization chamber;
A storage container for storing a predetermined amount of water in the sterilization chamber,
The storage container communicates with a water supply pipe that receives water from a water supply bottle provided outside the sterilization chamber, and a drain pipe for draining excess water while leaving a certain amount of water in the storage container. Provided,
Water in the water supply bottle is introduced into the storage container from the water supply pipe by preliminary decompression of the sterilization chamber by a vacuum pump, and the drain pipe is discharged so that excess water in the storage container is discharged from the drain pipe by raising the pressure in the sterilization chamber again. A certain amount of water is left in the storage container by setting the opening at a predetermined height position of the storage container,
The gist of the invention is that the vacuum pump is operated to decompress the sterilization chamber and the sterilization gas is introduced into the sterilization chamber in a state where a predetermined amount of water left in the storage container is stored in advance .

That is, the sterilizer according to the present invention operates in a state where a predetermined amount of water left in a storage container that stores a predetermined amount of water in the sterilization chamber is stored in advance , and a vacuum pump is operated to depressurize the sterilization chamber. Since sterilization gas is introduced into the sterilization chamber, water is not sucked up using the vacuum in the sterilization chamber as in the past, so the degree of vacuum in the sterilization chamber varies or the remaining amount of water in the water bottle changes. However, the amount of water introduced does not fluctuate. In addition, since the amount of water is not adjusted by the time for opening the solenoid valve as in the prior art, the remaining amount of water in the water supply piping does not affect the amount of water supply, so a constant amount of water is always supplied. In addition to maintaining a stable sterilized state, a reaction product of sterilization gas and water is hardly generated.

Further, the present invention is the storage container, the drainage with the water supply pipe communicates receiving the water supply from the water supply bottle provided outside the sterilization chamber, the excess water leaving a certain amount of water in the storage container A drainage pipe is provided, and water in the water bottle is introduced into the storage container from the water supply pipe by preliminary decompression of the sterilization chamber by a vacuum pump, and the excess water in the storage container is removed by raising the pressure in the sterilization chamber again. to leave the reservoir an amount of water opening of the drain pipe by Rukoto is set to a predetermined height position of the storage container so as to discharge from the drain pipe, certainly certain amount of water by vacuum and pressure recovery of the sterilization chamber It can be stored in a storage container, and can maintain a much more stable sterilized state as compared with conventional water volume management by valve operation.

  In the present invention, the drainage pipe is also used as a water supply pipe. When the excess water in the storage container is returned from the water supply pipe to the water supply bottle by raising the pressure in the sterilization chamber again, the drainage pipe is discharged. Water can be returned to the water bottle and reused, so water is not wasted and the water bottle needs to be replenished fewer times, thus reducing maintenance work.

  In the present invention, the storage container is provided with a flow opening for releasing vaporized water into the sterilization chamber, and is provided with a cover member that covers the opening of the water supply pipe and the surface of the stored water. In this case, the vaporized water vapor is surely released to the sterilization chamber, while the water sprayed from the opening of the water supply pipe is guarded so as not to scatter around the water, and the accurate water supply amount is secured, and the water surface is covered, Generation | occurrence | production of the reaction product of sterilization gas and water can be suppressed.

  In the present invention, the sterilization chamber is provided with a shielding plate having a flow opening for releasing vaporized water into the sterilization space, and is separated from the sterilization space in which an object to be sterilized is accommodated by the shielding plate. When the storage container is installed at a place, the vaporized water vapor can be reliably released into the sterilization space, and the generation of a reaction product of sterilization gas and water can be suppressed. Even if a small amount of reaction product is generated, it is blocked by the shielding plate, so that adverse effects on the sterilized product can be minimized.

  1 and 2 are views showing a sterilizer according to an embodiment of the present invention. 1A and 1B are diagrams showing a configuration as viewed from the exterior, in which FIG. 1A is a left side view, FIG. 1B is a front view, and FIG. 1C is a right side view. FIG. 2 is a diagram showing the configuration of the gas flow path.

In this embodiment, a negative pressure type gas sterilizer that performs processing such as sterilization while maintaining the sterilization chamber at atmospheric pressure or lower is illustrated, and an example using 100% concentration ethylene oxide gas as the sterilization gas is illustrated. I will explain. As the sterilization gas, not only a 100% concentration ethylene oxide gas but also a gas containing a dilution gas such as CO _{2 of} about several percent can be used.

  This sterilizer is filled with a sterilization chamber 1 in which an object to be sterilized is housed, a vacuum pump 2 for decompressing the inside of the sterilization chamber 1, and a liquefied sterilizing agent as a sterilization gas introduced into the sterilization chamber 1. A can holding unit 4 in which a cartridge can 3 that can be broken is inserted and held, and a can breaker as a can breaking means for punching the cartridge can 3 held in the can holding unit 4 with a punch needle 5 And a mechanism 6.

  In addition, a storage container 8 for storing a predetermined amount of water in the sterilization chamber 1 and a water supply bottle 9 provided outside the sterilization chamber 1 for supplying water to the storage container 8 through a water supply pipe 10 are provided. Yes. The water bottle 9 and the storage container 8 constitute a water supply mechanism 72.

  Furthermore, an adsorption tower 12 for adsorbing sterilization gas in the exhaust gas discharged from the sterilization chamber 1 and a catalytic combustion apparatus 13 for catalytic combustion of the sterilization gas in the exhaust gas discharged from the adsorption tower 12 are provided. The adsorption tower 12 and the catalytic combustion device 13 constitute a detoxification mechanism 73.

  More specifically, in the sterilizer, the sterilization chamber 1 is provided by a substantially rectangular can body inside the main body. In the sterilization chamber 1, an object to be sterilized is accommodated by, for example, a basket 20. The sterilization chamber 1 has an open part for putting in and out the sterilized object on the front surface of the apparatus, and an open / close door 21 is provided for hermetically sealing and closing the open part.

  When the opening / closing door 21 is opened, a can holding portion 4 for holding the cartridge can 3 is provided in the lower left part of the opening of the sterilization chamber 1. When the opening / closing door 21 is opened, the cartridge can insertion opening is opened. It is configured as follows. That is, the open / close door 21 functions as the open / close door 21 that closes the cartridge can insertion opening of the can holding portion 4. The can holding unit 4 is attached with a can breaking mechanism 6 for breaking the cartridge can 3.

  The opening / closing door 21 is provided with a locking mechanism 22 as a locking means for locking the opening / closing door 21 to be opened, and the opening / closing door 21 can be opened under a predetermined condition under the control of a control means (not shown). It is configured to control locking and unlocking.

  A vacuum pump 2 is connected to the sterilization chamber 1 through an exhaust passage 25 so that the inside of the sterilization chamber 1 can be depressurized. The exhaust passage 25 is provided with an exhaust valve 30 for turning on and off the flow of exhaust gas, and a first pressure sensor 33 for detecting the pressure in the sterilization chamber 1 is provided upstream of the exhaust valve 30. ing. A heater 74 is wound around the outer periphery of the sterilization chamber 1 so as to heat the sterilization chamber 1 to a predetermined sterilization temperature.

  Further, a dilution path 26 for introducing diluted air for diluting the exhaust gas flowing through the exhaust path 25 is connected so as to merge with the exhaust path 25. The dilution path 26 is provided with a dilution filter 29 for filtering dilution air and a dilution valve 31 for turning on and off the flow of dilution air.

  On the other hand, the sterilization chamber 1 is connected with an intake passage 27 for sucking air into the sterilization chamber 1. The intake passage 27 is provided with an intake filter 28 for filtering the intake air and an intake valve 32 for turning on and off the intake air flow.

  Further, on the downstream side of the vacuum pump 2, a first removal path 35 for introducing exhaust gas diluted with dilution air into the adsorption tower 12 is provided. A first abatement valve 37 is provided to turn on and off the flow of exhaust gas to and from. On the downstream side of the adsorption tower 12, a second abatement path 41 for introducing exhaust gas discharged from the adsorption tower 12 into the catalytic combustion apparatus 13 is provided. A second abatement valve 38 for turning on / off the flow of the exhaust gas to 13 is provided.

  A second pressure sensor 34 for detecting the pressure of the exhaust gas is provided in the gas flow path downstream of the vacuum pump 2 and upstream of the abatement means including the adsorption tower 12 and the catalytic combustion device 13.

  Cooling fins 40 for cooling the exhaust gas discharged from the catalytic combustion device 13 are provided on the downstream side of the catalytic combustion device 13 so that the exhaust gas cooled by the cooling fin 40 is discharged from the discharge passage 42. It has become. In addition, a bypass path 36 that bypasses the upstream side of the first abatement path 35 and the discharge path 42 is provided, and a bypass valve 39 that opens and closes the bypass is provided in the bypass path 36. Exhaust gas can be discharged without passing through the adsorption tower 12 and the catalytic combustion device 13.

  Further, a second bypass passage 36b that bypasses the upstream side of the second removal passage 41 from the second removal valve 38 and the downstream side of the first bypass passage 39a of the first bypass passage 36a is provided. The second bypass passage 36b is provided with a second bypass valve 39b for opening and closing the bypass. Thus, when the catalyst temperature sensor 68 detects a catalyst temperature abnormality of the catalytic combustion device 13, the second abatement valve 38 is closed and the second bypass valve 39 b is opened, and the exhaust gas is not introduced into the catalytic combustion device 13. In addition, the first bypass path 36a is discharged to the discharge path 42 via the second bypass path 36b. Thereby, exhaust gas is introduced into the catalytic combustion apparatus 13 where the catalyst temperature abnormality has occurred, and troubles such as explosion are prevented. At this time, the adsorbent is also regenerated in the adsorption tower 12, and after the abnormality of the catalyst temperature occurs, the operation is controlled to continue until the adsorbent is regenerated and then stopped. It can be used.

  The water supply pipe 10 that connects the storage container 8 and the water supply bottle 9 in the sterilization chamber 1 is provided with a water supply valve 15 that turns on / off the water supply from the water supply bottle 9 to the storage container 8. The water supply bottle 9 is provided with a float switch 16 for detecting the amount of water in the water supply bottle 9.

  Next, the can holding unit 4 and the can breaking mechanism 6 will be described in detail.

  As shown in FIG. 3, the can holding portion 4 is formed in a cylindrical shape into which the cartridge can 3 is inserted, and an opening at one end of the cylindrical shape is opened when the opening / closing door 21 is opened as a cartridge can insertion port 59. Are arranged to be. The cartridge can 3 is inserted with the head 53, which is the side to be broken by perforation by the perforation needle 5, facing the back.

  A cylinder 51 and a piston 50 that advances and retreats in the cylinder 51 are arranged on the back side of the can holding part 4 opposite to the cartridge can insertion port 59. The cylinder 51 is formed with a head insertion recess 60 for inserting the head 53 of the cartridge can 3 on the connecting portion side with the can holding portion 4. A seal member 54 having 55 is disposed. The internal space of the cylinder 51 and the head insertion recess 60 are communicated with each other through the communication hole 55.

  On the other hand, a piercing needle 5 for piercing and breaking the head 53 of the cartridge can 3 is attached to the tip of the piston 50. In addition, a seal ring 52 is attached to the outer peripheral surface of the piston 50 to ensure airtightness with the inner peripheral surface of the cylinder 51.

  The rear end portion of the piston 50 is connected to a crank 47 that is rotated by a motor 45 via a connecting rod 48, and the piston is slid forward and backward by rotating the crank 47 by the motor 45. Has been. As the piston 50 advances and retreats, the piercing needle 5 moves back and forth to pierce the head 53 of the cartridge can 3. In other words, the can breaking mechanism 6 as a can breaking means is configured to drive the piercing needle 5 by a mechanical drive means not depending on the pressure difference of the sterilization chamber 1 under reduced pressure.

  A limit switch 46 as a detecting means for detecting the position of the piercing needle 5 of the can breaking mechanism 6 is disposed at the rear portion of the crank 47, and the limit switch 46 is provided by a pushing portion 49 protruding from the outer peripheral portion of the crank 47. Is to be turned on. The punching portion 49 is provided at a position where it comes into contact with the limit switch 46 when the piston 50 on the outer periphery of the crank 47 is retracted most. When the punching portion 49 turns on the limit switch 46, the punch needle 5 The most retracted position is detected.

  On the other hand, the seal member 54 provided in the head insertion recess 60 is in close contact with the head 53 of the cartridge can 3 in an annular shape to ensure a seal. The piercing needle 5 is configured to pierce the center of the annular seal portion back and forth in the communication hole 55 of the seal member 54, and is secured in the cylinder 51 before the tip of the piston 50. A sterilizing gas is ejected from the perforated hole into the space.

  That is, the space in which the gas is ejected functions as a gas receiving space 56 for communicating with the sterilization chamber 1 and receiving the gas ejected by the rupture can into the sterilization chamber 1 and introducing it into the sterilization chamber 1. The sterilizing gas ejected into the gas receiving space 56 is introduced into the sterilization chamber 1 through the gas flow path 57. At this time, the sealing member 54 formed in the opening of the gas receiving space 56 is in close contact with the head 53 of the inserted cartridge can 3 to ensure the sealing of the gas receiving space 56.

  On the other hand, the opening / closing door 21 is formed with a pressing portion 58 that presses the rear portion of the cartridge can 3 inserted into the can holding portion 4 with the opening / closing door 21 closed, and the cartridge can 3 is inserted into the can holding portion 4. Then, by closing the open / close door 21, the cartridge can 3 is pressed from the butt toward the head 53, and the close contact between the seal member 54 and the head 53 of the cartridge can 3 is ensured. .

  Therefore, if a cartridge can 3 of a different size is inserted into the can holding portion 4 by mistake, the rear portion (butt portion) of the cartridge can 3 interferes with the pressing portion 58 of the open / close door 21 if the cartridge can 3 is large. The door 21 does not close sufficiently. On the other hand, if the cartridge can 3 is small, the rear portion (butt portion) of the cartridge can 3 is not sufficiently pressed by the pressing portion 58 of the open / close door 21, so that the seal member 54 and the head 53 of the cartridge can 3 are in close contact. The seal is insufficient.

  In this sterilizer, the lock mechanism 22 operates to lock the opening of the door 21 with the door 21 closed. As the lock mechanism 22, for example, a hole opening plate 23 provided on the opening / closing door 21 side is inserted into the plunger unit 24 with the opening / closing door 21 closed, and an electromagnetic plunger (not shown) operates to operate the hole opening plate 23. It is possible to employ a mechanism that prevents the opening / closing door 21 from being opened by inserting a hook into the hole.

  The sterilizer is configured to accept insertion of a new cartridge can 3 into the can holding part 4 after detecting that the piercing needle 5 is at a predetermined initial position by a limit switch 46 as a detecting means. . That is, the control means (not shown) controls the lock mechanism 22 to be unlocked after the limit switch 46 detects that the perforating needle 5 is the most retracted position, which is a predetermined initial position. When the lock is released, the door 21 is opened for the first time so that a new cartridge can 3 can be inserted into the can holding portion 4.

  FIG. 4 is a view for explaining a state in which the cartridge can 3 held by the can holding unit 4 is pierced by the can breaking mechanism 6.

  First, as shown in FIG. 4A, the initial state set as the predetermined initial position is a state in which the pushing portion 49 of the crank 47 pushes the limit switch 46, and the position where the punch needle 5 is most retracted. It is. Next, when the cartridge can 3 is inserted and the sterilization chamber 1 reaches a predetermined degree of vacuum, the motor 45 is driven to rotate and the crank 47 rotates once. 4 (B) shows a state where the piston 50 and the piercing needle 5 are advanced, FIG. 4 (C) shows a state where the piston 50 and the piercing needle 5 are most advanced, and FIG. In this state, the piercing needle 5 is retracted. Then, the rotation of the motor 45 is controlled to stop when the pushing portion 49 of the crank 47 reaches the most retracted position by pressing the limit switch 46 again. The cartridge can 3 is broken by such a back-and-forth movement of the piercing needle 5.

  Next, the water supply mechanism 72 to the sterilization chamber 1 using the water supply bottle 9 and the storage container 8 will be described in detail.

  FIG. 5 is a view showing an example of the water supply bottle 9. This water supply bottle 9 is provided outside the sterilization chamber 1, a water supply pipe 10 for supplying water is inserted into the storage container 8 of the sterilization chamber 1, and the tip opening is arranged to open near the bottom of the water supply bottle 9. ing. In this example, the water supply pipe 10 also serves as a drain pipe for draining excess water while leaving a certain amount of water in the storage container 8.

  In addition, a float switch 16 for detecting the remaining amount of the stored water is inserted into the water supply bottle 9. The float switch 16 detects that the float 17 provided near the bottom of the water bottle 9 has moved downward and the liquid level has approached the bottom of the water bottle, and sends a detection signal to a control means (not shown). ing.

  FIG. 6 shows a storage container 8 that is provided in the sterilization chamber 1 and stores a predetermined amount of water in the sterilization chamber 1. A water supply pipe 10 that receives water from a water supply bottle 9 provided outside the sterilization chamber 1 communicates with the storage container 8, and excess water is drained while leaving a certain amount of water in the storage container 8. A drain pipe (also serving as the water supply pipe 10) is provided. That is, in this example, the water supply pipe 10 also serves as a drain pipe.

  The storage container 8 has a rectangular parallelepiped shallow box shape opened on the upper surface, and the water supply pipe 10 that also serves as the drain pipe penetrates the bottom of the storage container 8 and communicates with the opening 7 protruding into the internal space. ing. The water supply pipe 10 also serving as the drain pipe introduces the water in the water supply bottle 9 from the water supply pipe 10 into the storage container 8 by preliminary decompression of the sterilization chamber 1 by the vacuum pump 2 and returns the sterilization chamber 1 to atmospheric pressure again. Thus, the opening 7 of the water supply pipe 10 is set at a predetermined height position of the storage container 8 so that excess water in the storage container 8 is discharged from the water supply pipe 10 also serving as a drain pipe and returned to the water supply bottle 9.

  Thus, the vacuum pump 2 is operated in a state where a predetermined amount of water is stored in the storage container 8 in advance, and the inside of the sterilization chamber 1 is decompressed, and the sterilization gas is introduced into the sterilization chamber 1.

  The storage container 8 is provided with a cover member 11 that covers a part of the upper surface opening. In the cover member 11, a circulation opening 14 for discharging vaporized water into the sterilization chamber 1 is secured in the shape of a long and narrow slit along the four surrounding sides. The cover member 11 covers the opening 7 of the water supply pipe 10 and the water surface of the stored water.

  Further, as shown in FIG. 2, a shielding plate 18 is provided in the sterilization chamber 1 in a state in which a flow opening 43 for discharging vaporized water to the sterilization space 19 is secured. The storage container 8 is installed in a place separated from the sterilization space 19 in which an article to be sterilized is stored. Further, the sterilization gas ejected from the cartridge can 3 is introduced into the sterilization chamber 1 from a gas introduction part 70 provided at a location separated from the sterilization space 19 by the shielding plate 18. As described above, even if a reaction product of water and sterilization gas is generated by providing the gas introduction part 70 and the storage container 8 at a place separated from the sterilization space 19 by the shielding plate 18, The impact on is minimized.

  FIG. 7 shows a state where water is supplied into the sterilization chamber 1 by the water supply mechanism 72. That is, first, the vacuum pump 2 is operated to depressurize the interior of the sterilization chamber 1, and when the predetermined degree of vacuum is reached, the water supply valve 15 is opened. Then, due to the pressure difference between the pressure in the sterilization chamber 1 and the atmospheric pressure, the water in the water supply bottle 9 is sucked into the storage container 8 through the water supply pipe 10 as shown in FIG. At this time, water is supplied so that the water level of the water introduced into the storage container 8 reaches above the projected opening 7 of the water supply pipe 10.

  Control of the water supply amount at this time is performed by appropriately controlling the valve opening time of the water supply valve 15 corresponding to the degree of vacuum of the sterilization chamber 1. The water supply amount at this time may be within a range where the water surface in the storage container 8 is at least above the opening 7 of the water supply pipe 10 and does not overflow from the upper end opening edge of the storage container 8. Even if variations occur, there is no problem as long as it is within the above range. At this time, since the opening 7 is covered with the cover member 11, it is possible to prevent the water ejected from the opening 7 from being scattered to the surroundings and to ensure an accurate water supply amount.

  Next, by introducing air into the sterilization chamber 1 and returning the pressure in the sterilization chamber 1 to near atmospheric pressure, as shown in FIG. 7B, the opening 7 of the water supply pipe 10 that also serves as a drain pipe is used. The water up to the top is discharged from the water supply pipe 10 and returned to the water supply bottle 9. The water discharge at this time stops when the water level drops to the height of the opening 7, and a certain amount of water remains in the storage container 8. Thereafter, the inside of the sterilization chamber 1 is evacuated, sterilization gas is introduced, water remaining in the storage container 8 is vaporized and discharged into the sterilization chamber 1, and sterilization is performed.

  In this way, since the height of the opening 7 in the storage container 8 is kept constant, a constant amount of water always remains in the storage container 8, so that a constant amount of water is always introduced into the sterilization chamber 1. It becomes possible.

  FIG. 8 is a modification of the water supply mechanism 72. In either case, water is once introduced to the height of the chain line by depressurization of the sterilization chamber 1, and then the pressure in the sterilization chamber 1 is increased to leave water at the illustrated water level.

  In FIG. 8A, the water supply pipe 10 does not protrude into the storage container 8, but the water supply pipe 10 is open on the bottom surface of the storage container 8, and the remaining amount of water is the side where the water supply pipe 10 is open. It is set according to the height of the weir member 61 provided in the water, and water is left at the water level at the height of the weir member 61.

  In FIG. 8B, the water supply pipe 10 does not protrude through the bottom of the storage container 8, but the water supply pipe 10 is open on the side surface of the storage container 8, and the remaining amount of water is the water supply pipe 10. Is set according to the height of the opening, and water is left at the level of the lower end of the opening edge.

  In FIG. 8C, the water supply pipe 10 and the drain pipe are not used together, but water is supplied from the upper opening of the storage container 8 through the water supply pipe 10a dedicated to water supply. The remaining amount of water is set by the height at which the drain pipe 10b is opened, and water is left at the level of the opening edge. In the figure, 44 is a drain valve.

  Next, a detoxification mechanism 73 as a detoxifying means for detoxifying the sterilized gas discharged from the sterilization chamber 1 by the vacuum pump 2 using the adsorption tower 12 and the catalytic combustion apparatus 13 will be described in detail.

  The adsorption tower 12 is filled with, for example, an adsorbent in a cylindrical case, and adsorbs and removes ethylene oxide which is a sterilized gas component in the exhaust gas introduced into the adsorption tower 12. As the adsorbent, for example, activated carbon, zeolite, silica gel, activated alumina and the like can be used. In particular, activated carbon can be suitably used because the adsorbed ethylene oxide gas can be desorbed relatively easily. These adsorbents can be used alone or in combination.

  The catalyst combustion device 13 is filled with a catalyst and heated to a predetermined temperature, thereby decomposing and detoxifying ethylene oxide gas in the exhaust gas by catalytic combustion, and discharging it from the discharge path 42. .

  As the catalyst used in the catalytic combustion apparatus 13, noble metal catalyst can be suitably used because combustion proceeds at a low temperature and low concentration ethylene oxide gas can be catalytically combusted. As such a noble metal catalyst, for example, platinum, rhodium, palladium or the like can be suitably used, and a catalyst in which these noble metals are supported on an appropriate carrier such as silica, alumina, zeolite or the like can be used.

  FIG. 9 is a partially broken sectional view showing the catalytic combustion apparatus 13.

  In the catalytic combustion apparatus 13, the upper layer of the cylindrical case 69 is filled with the ceramic 65, and the lower layer is filled with the catalyst 66 described above. The ceramic 65 is filled for the diffusion of the supply gas and the heating of the supply gas. For example, a ceramic ball or the like can be used. While the supply gas flows through the gap between the filled ceramic balls, the supply gas is heated by the heat of the stored ceramic balls.

  The heaters 62 and the preheating pipes 63 are wound around the outer periphery of the case 69 alternately around the catalyst layer filled with the catalyst 66. The heater 62 heats the catalyst 66 and the preheating pipe 63, and the preheating pipe 63 circulates the exhaust gas introduced into the catalyst layer and preheats it. The heater 62 and the preheating pipe 63 are covered with a heat conductive fixing material 64 and then covered with a heat insulating material (not shown) from above. As the heat conductive fixing material 64, for example, heat transfer cement can be used.

  In addition to the heater temperature sensor 67 for monitoring the temperature of the heater 62, a catalyst temperature sensor 68 for monitoring the temperature of the catalyst 66 is provided. In this way, not only the heater temperature sensor 67 but also the catalyst temperature sensor 68 directly monitors the temperature of the catalyst 66.

  However, ethylene oxide gas has an explosion limit concentration of 3% by volume, and when exhaust gas exceeding this concentration flows into the catalytic combustion device 13, for example, a device that only monitors the temperature of the heater (Patent Document 2). Then, the temperature of the catalyst instantly becomes high before the temperature sensor of the heater detects it, which is extremely dangerous. Also, if the heater goes out of control for some reason, there is a possibility of a major accident and the danger is great. Moreover, heat loss is large with a structure in which a heater is simply wound around a reactor.

  In contrast, in this embodiment, the heaters 62 and the preheating pipe 63 are alternately wound, and the heaters 62 and the preheating pipe 63 are not directly covered with the heat insulating material, but are once fixed with a heat conductive fixing material. Since the double coating of covering with heat insulating material is performed, the heat of the heater 62 is smoothly transferred to the preheating pipe 63 and the catalyst 66, heat loss is reduced, and the temperature rise of the catalyst 66 at the initial stage of operation can be sharpened. Thus, the rise time of the apparatus can be shortened.

  On the other hand, in this embodiment, compared with the case where the temperature control is performed only for the heater, the heating runaway of the heater is suppressed and safety is drastically improved, and a high concentration sterilization gas is introduced for some reason. In such a case, it is possible to quickly detect an abnormality in the catalyst temperature and take measures such as turning off the heater power supply, and further safety can be ensured.

  Next, control of the sterilizer will be described.

  The sterilization method of the present embodiment is realized by controlling devices, valves, sensors, the vacuum pump 2 and the like that respectively constitute the can breaking mechanism 6, the water supply mechanism 72, and the abatement mechanism 73 by a control means (not shown).

[Cartridge can / sterilized material acceptance process]
First, in the initial state, the door 21 is closed and the door 21 is locked by the lock mechanism 22. Next, when the power of the apparatus is turned on, it is confirmed that the limit switch 46 of the can breaking mechanism 6 is pushed by the pushing portion 49 of the crank 47 and the piston 50, that is, the punch needle 5 is in the most retracted initial position. . After confirming the initial position of the piercing needle 5, the lock mechanism 22 is unlocked, the opening / closing door 21 is allowed to open, and the cartridge can 3 can be received.

  Next, when the user opens the open / close door 21, the cartridge can 3 is inserted into the can holding unit 4, an object to be sterilized is accommodated in the sterilization chamber 1, and the open / close door 21 is closed, an instruction operation for starting a sterilization process is input. Accept. This instruction operation input can be received by the touch panel 75 on the front surface of the apparatus. If the input of the said instruction | indication operation is received, the door 21 will be locked by the locking mechanism 22, and it will progress to the next step.

[Water supply process]
First, the inside of the sterilization chamber 1 is decompressed by operating the vacuum pump 2 with the bypass valve 39 and the exhaust valve 30 opened and the other valves closed. When driving of the vacuum pump 2 is started, if the pressure drop in the sterilization chamber 1 is slower than a predetermined set time by the first pressure sensor 33, an abnormality of the vacuum pump 2, a door portion, a cartridge portion, etc. Since there is a possibility of an airtight abnormality, an alarm is provided by an alarm lamp on the front of the apparatus as a notification means, a buzzer (not shown), or the like, and an abnormality is notified by not proceeding to the next step.

  In addition, when the vacuum pump 2 starts to be driven and the pressure on the side of the abatement mechanism 73 becomes higher than a predetermined set value by the second pressure sensor 34, an abnormality in the valve of the abatement mechanism 73 or Since there is a possibility of an abnormality such as clogging of the flow path, an alarm is given by an alarm lamp 71 on the front of the apparatus as a notification means, a buzzer (not shown) or the like, and the abnormality is notified by not proceeding to the next step. Further, when the float switch 16 of the water supply bottle 9 detects that the remaining amount of water in the water supply bottle 9 is equal to or less than a predetermined set value, an alarm lamp 71 on the front of the apparatus as a notification means, a buzzer (not shown) or the like warns. At the same time, the abnormality is notified by not proceeding to the next step.

  When the abnormality is not notified, the process proceeds to the next step, and when the sterilization chamber 1 is depressurized to a predetermined vacuum level (for example, about −20 kPa), the vacuum pump 2 is stopped and the exhaust valve 30 and the bypass valve 39 are closed. The water supply valve 15 is opened for a predetermined time, and the water in the water supply bottle 9 is sucked into the storage container 8. At this time, by setting the valve opening time of the water supply valve 15 according to the degree of vacuum in the sterilization chamber 1, water is supplied to a level above the opening 7 of the water supply pipe 10 of the storage container 8 and the water supply valve 15 is closed. .

  Next, the intake valve 32 is opened, air is introduced into the sterilization chamber 1 to return the pressure in the sterilization chamber 1 to near atmospheric pressure, and the water supply valve 15 is opened again. Is returned to the water supply bottle 9. In the storage container 8, a certain amount of water remains at the level of the opening 7 of the water supply pipe 10 that also serves as a drain pipe. After the pressure in the sterilization chamber 1 is returned to near atmospheric pressure, the intake valve 32 and the water supply valve 15 are closed.

[Sterilization gas introduction process]
First, the vacuum pump 2 is operated with the exhaust valve 30 and the bypass valve 39 opened, the heater 74 in the sterilization chamber 1 is turned on, and the sterilization chamber 1 is heated and depressurized. The first pressure sensor 33 detects that the inside of the sterilization chamber 1 has been lowered to a predetermined degree of vacuum (for example, about −85 kPa), and the inside of the sterilization chamber 1 is heated to a predetermined sterilization temperature (for example, about 40 to 55 ° C.). If it is detected by a temperature sensor (not shown), the process proceeds to the next step. Here, if either the degree of vacuum or temperature does not reach the predetermined value, the process does not proceed to the next step, and if the state continues for a predetermined time or longer, it is determined that there is an abnormality and an alarm on the front of the apparatus as a notification means Alarm is given by a lamp or buzzer (not shown).

  In the next step, first, the bypass valve 39 and the exhaust valve 30 are closed, and the vacuum pump 2 is stopped. Next, the motor 45 is driven to break the cartridge can 3 from the initial position where the limit switch 46 of the can break mechanism 6 is pushed by the pushing portion 49 of the crank 47 and the piston 50, that is, the punch needle 5 is most retracted. The motor 45 is rotated once until the limit switch 46 is pressed, and then stops when the limit switch 46 is pressed.

[Sterilization process]
After the introduction of the sterilization gas, the temperature control of the heater 74 in the sterilization chamber 1 is continued as it is, and a sterilization process is performed for a predetermined time (for example, about 3 to 6 hours).

  At the stage where the sterilization process is nearing the end (for example, about 90 minutes before the start of the exhaust process), an exhaust preparation process is performed in parallel with the sterilization process. First, the dilution valve 31, the first removal valve 37, and the second removal valve 38 are opened, the vacuum pump 2 is operated, and air is circulated through the adsorption tower 12 and the catalytic combustion apparatus 13. Next, the heater 62 of the catalytic combustion apparatus 13 is turned on to heat the catalyst 66 and the preheating pipe 63. After a predetermined sterilization time has elapsed and the heater temperature sensor 67 and the catalyst temperature sensor 68 detect that the heater 62 and the catalyst 66 have reached a predetermined temperature (for example, about 300 to 320 ° C.), the process proceeds to the next step. .

[Exhaust process]
The diluting valve 31 and the exhaust valve are opened while the first abatement valve 37 and the second abatement valve 38 are opened to continue the operation of the vacuum pump 2 and the temperature control of the heater 62 and the catalyst 66 of the catalytic combustion apparatus 13 is continued. 30 are alternately opened, and the inside of the sterilization chamber 1 is depressurized. Since a large amount of sterilizing gas is discharged at the initial stage of exhaust, the opening time of the dilution valve 31 is made longer than the opening time of the exhaust valve 30 to increase the dilution rate, and the exhaust is gradually exhausted as the exhaust proceeds. Since the amount of sterilization gas decreases, control is performed to gradually increase the valve opening time of the exhaust valve 30.

  When the pressure is reduced to a predetermined degree of vacuum, the dilution valve 31 is opened while the vacuum pump 2 is in operation and air is passed to the abatement mechanism 73 side, the exhaust valve 30 is closed, the intake valve 32 is opened, and the sterilization chamber 1 is opened. Return the pressure to atmospheric pressure.

[Aeration process]
The decompression and the restoration to the atmospheric pressure performed in the exhaust process are repeated a plurality of times, and the sterilization gas remaining in the sterilization chamber 1 is almost completely discharged. Next, the dilution valve 31 is closed, the exhaust valve 30 and the intake valve 27 are opened, air is circulated in the sterilization chamber 1, the air in the sterilization chamber 1 is replaced, and the remaining sterilization gas is completely discharged.

  During the exhaust to aeration process, the temperature control of the heater 62 and the catalyst 66 of the catalytic combustion apparatus 13 is continued, and the detoxification is continuously performed. At this time, the heater 62 of the catalytic combustion device 13 is turned off when the temperature of the catalyst 66 exceeds + 20 ° C. to prevent the temperature in the catalytic combustion device 13 from rising excessively.

  In addition, since the exhaust gas to be introduced into the adsorption tower 12 and the catalytic combustion apparatus 13 is diluted with diluted air and introduced, the concentration of sterilizing gas flowing through the exhaust gas treatment system decreases as a whole, greatly increasing the risk of ignition and explosion. To drop.

  In particular, by controlling the amount of diluted air introduced so that the concentration of the sterilizing gas discharged from the adsorption tower 12 is below the explosion limit, the risk of ignition and explosion can be almost completely eliminated. In particular, in a negative pressure sterilizer using a high-concentration sterilization gas, it becomes possible to make the exhaust gas harmless safely and efficiently, and the safety of the surrounding environment of the sterilizer can be improved. It goes without saying that a safe and efficient detoxification process can also be performed in a positive pressure sterilizer.

  In addition, when dilution air is constantly introduced into the adsorption tower 12 and the catalytic combustion apparatus 13, the pressure fluctuation of the fluid in the exhaust gas treatment system is reduced and stabilized, and the aging of the apparatus can be prevented to some extent. Moreover, since dilution air always flows into the catalytic combustion apparatus 13, overheating of the catalytic combustion apparatus 13 and the like can be prevented, and safety can be further improved.

  When the aeration is completed, the vacuum pump 2 is stopped, the heater 74 of the sterilization chamber 1 and the heater 62 of the catalytic combustion device 13 are turned off, all the valves are closed, the lock mechanism 22 of the open / close door 21 is unlocked, and sterilization is performed. The article to be sterilized after processing and the cartridge can 3 after use can be taken out. When the user takes out the article to be sterilized and the used cartridge can 3, the operation input for the end process is accepted, and the lock mechanism 22 is activated to lock the door 21 by accepting the input operation on the touch panel 75. finish.

  As described above, according to the sterilizer, the vacuum pump 2 is operated in a state where a predetermined amount of water is stored in the storage container 8 that stores a predetermined amount of water in the sterilization chamber 1. In order to introduce sterilization gas into the sterilization chamber, the water is not drawn up using the vacuum in the sterilization chamber 1 as in the prior art. Even if the remaining amount of water fluctuates, the amount of water introduced does not fluctuate. In addition, since the amount of water is not adjusted by the time for opening the solenoid valve as in the prior art, the remaining amount of water to the water supply pipe 10 does not affect the amount of water supply. It can be performed and maintains a stable sterilized state, and hardly produces a reaction product of sterilization gas and water.

  A water supply pipe 10 that receives water from a water supply bottle 9 provided outside the sterilization chamber 1 communicates with the storage container 8, and extra water is left in the storage container 8 while leaving a certain amount of water. A drainage pipe for draining (also serving as the water supply pipe 10) is provided, and water in the water supply bottle 9 is introduced into the storage container 8 from the water supply pipe 10 by preliminary decompression of the sterilization room 1 by the vacuum pump 2, and the sterilization room The opening 7 of the drainage pipe (also serving as the water supply pipe 10) is used as a storage container so that excess water in the storage container 8 is discharged from the drainage pipe (also serving as the water supply pipe 10) by raising the pressure in 1 again. 8 is set at a predetermined height of 8 so that a certain amount of water can be reliably stored in the storage container 8 by depressurization and return pressure of the sterilization chamber 1, which is much higher than conventional water amount management by valve operation. Stable sterilization state.

  Further, the drainage pipe is also used as the water supply pipe 10, and the excess water in the storage container 8 is returned from the water supply pipe 10 to the water supply bottle 9 by raising the pressure in the sterilization chamber 1 again. Since the discharged water can be returned to the water supply bottle 9 and reused, water is not wasted, and the number of times of water replenishment to the water supply bottle 9 can be reduced, and maintenance work can be saved.

  The storage container 8 has a flow opening 14 for releasing vaporized water into the sterilization chamber 1, and a cover member 11 that covers the opening of the water supply pipe 10 and the surface of the stored water. Since it is provided, the vaporized water vapor can be reliably discharged to the sterilization chamber 1 while the water sprayed from the opening 7 of the water supply pipe 10 is guarded so as not to scatter to the surroundings, and an accurate water supply amount can be secured. Therefore, generation of a reaction product of sterilization gas and water can be suppressed.

  The sterilization chamber 1 is provided with a shielding plate 18 having a flow opening 43 for releasing vaporized water into the sterilization space 19, and the sterilization space in which an object to be sterilized is accommodated by the shielding plate 18. Since the storage container 8 is installed at a location separated from the gas 19, the vaporized water vapor can be reliably discharged into the sterilization space 19, and the generation of a reaction product of sterilization gas and water can be suppressed. Even if a small amount of reaction product is generated, it is blocked by the shielding plate 18, so that adverse effects on the sterilized material can be minimized.

  In the above embodiment, the present invention is applied to a negative pressure type sterilizer that performs sterilization while maintaining the inside of the sterilization chamber 1 at a slightly lower negative pressure than the atmospheric pressure. However, the present invention is not limited to this, and the present invention can also be applied to a positive pressure type sterilizer in which the inside of the sterilization chamber 1 is maintained at a slightly higher positive pressure than the atmospheric pressure and sterilization is performed.

  Moreover, in the said embodiment, although the example which used the ethylene oxide gas as a sterilization gas of a sterilizer was shown, it is not limited to this, Various gas is applicable if it has a sterilization effect | action Can do. Moreover, it is possible to use an appropriate adsorbent other than those exemplified in the above description according to the type of sterilization gas.

It is an external appearance block diagram which shows the sterilizer of one Embodiment of this invention. It is a schematic block diagram of the said sterilizer. It is a figure which shows a can breaking means. It is a figure which shows the effect | action of the said can breaking means. It is a figure which shows a water supply bottle. It is a figure which shows a storage container. It is a figure which shows the effect | action of the said storage container. It is a figure which shows the modification of a storage container. It is a figure which shows structures, such as reaction.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1: Sterilization chamber 2: Vacuum pump 3: Cartridge can 4: Can holding part 5: Perforation needle 6: Can break mechanism 7: Opening 8: Storage container 9: Water supply bottle 10: Water supply pipe 10a: Water supply pipe 10b: Drain pipe 11 : Cover member 12: Adsorption tower 13: Catalytic combustion device 14: Flow opening 15: Water supply valve 16: Float switch 17: Float 18: Shielding plate 19: Sterilization space 20: Car 21: Open / close door 22: Lock mechanism 23: Hole plate 24: Plunger unit 25: Exhaust path 26: Dilution path 27: Intake path 28: Intake filter 29: Dilution filter 30: Exhaust valve 31: Dilution valve 32: Intake valve 33: First pressure sensor 34: Second pressure sensor 35: First abatement path 36a: first bypass path 36b: second bypass path 37: first abatement valve 38: second abatement valve 39a: first bypass valve 39b: second bypass valve 40: cooling fin 4 : Second abatement path 42: discharge path 43: flow opening 44: drain valve 45: motor 46: limit switch 47: crank 48: connecting rod 49: pushing part 50: piston 51: cylinder 52: seal ring 53: head Portion 54: Seal member 55: Communication hole 56: Gas receiving space 57: Gas passage 58: Pressing portion 59: Cartridge can insertion port 60: Head insertion recess 61: Weir member 62: Heater 63: Preheating pipe 64: Adhering material 65: Ceramic 66: Catalyst 67: Heater temperature sensor 68: Catalyst temperature sensor 69: Case 70: Gas introduction part 71: Alarm lamp 72: Water supply mechanism 73: Detoxification mechanism 74: Heater 75: Touch panel

Claims (4)

A sterilization chamber in which objects to be sterilized are stored;
A vacuum pump for depressurizing the sterilization chamber;
A storage container for storing a predetermined amount of water in the sterilization chamber,
The storage container communicates with a water supply pipe that receives water from a water supply bottle provided outside the sterilization chamber, and a drain pipe for draining excess water while leaving a certain amount of water in the storage container. Provided,
Water in the water supply bottle is introduced into the storage container from the water supply pipe by preliminary decompression of the sterilization chamber by a vacuum pump, and the drain pipe is discharged so that excess water in the storage container is discharged from the drain pipe by raising the pressure in the sterilization chamber again. A certain amount of water is left in the storage container by setting the opening at a predetermined height position of the storage container,
A sterilizer configured to operate a vacuum pump to depressurize the sterilization chamber and introduce a sterilization gas into the sterilization chamber in a state where a predetermined amount of water left in the storage container is stored in advance . The sterilizer according to claim 1, wherein the drainage pipe is also used as a water supply pipe, and the excess water in the storage container is returned from the water supply pipe to the water supply bottle by raising the pressure in the sterilization chamber again. Above the storage container, with flow openings for discharging the vaporized water sterilization chamber is secured, the water feed pipe opening and the reservoir claims 1 or cover member for covering the water surface is provided in the water 2. Sterilizer according to 2 . The sterilization chamber is provided with a shielding plate having a flow opening for releasing vaporized water into the sterilization space, and the storage is separated from the sterilization space in which the object to be sterilized is accommodated by the shielding plate. The sterilizer according to any one of claims 1 to 3, wherein a container is installed.

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