Sterilization device

Abstract

To suppress fatigue failure of a sterilization unit resulting from a cooling process.SOLUTION: A sterilization unit 1 comprises: an inner can 2 having an inner can space 4 in which an object to be sterilized is disposed; an outer can 3 disposed around the inner can 2 such that an outer can space 5 is formed between itself and the inner can 2; a sterilizing gas supply unit 10 which supplies sterilizing gas to the inner can space 4 in sterilization treatment on the object to be sterilized; and a cooling water supply unit 90 which, in a cooling process after sterilization treatment, supplies to the outer can space 5 second cooling water with a second temperature lower than a first temperature after supplying to the outer can space 5 first cooling water with a first temperature lower than a sterilization temperature of the object to be sterilized.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The technology disclosed herein relates to a sterilization device. [Background technology]

[0002] In the technical field of sterilization devices, a steam sterilization device such as that disclosed in Patent Document 1 is known. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2018-064878 Summary of the Invention [Problem to be solved by the invention]

[0004] In a steam sterilizer, the sterilization target is sterilized using high-temperature steam. After the sterilization process is completed, the target is cooled before being removed from the sterilizer. If the sterilizer is cooled too quickly, at least a portion of the sterilizer may be subject to fatigue failure.

[0005] The technology disclosed in this specification aims to suppress fatigue failure of a sterilization device caused by cooling treatment. [Means for solving the problem]

[0006] This specification discloses a sterilization apparatus comprising: an inner can having an inner can space in which an object to be sterilized is placed; an outer can arranged around the inner can so that an outer can space is formed between the inner can and the outer can; a sterilization gas supply unit that supplies sterilization gas to the inner can space during sterilization of the object to be sterilized; and a cooling water supply unit that supplies first cooling water at a first temperature lower than the sterilization temperature of the object to the outer can space and then supplies second cooling water at a second temperature lower than the first temperature to the outer can space during cooling after the sterilization. [Effects of the Invention]

[0007] The technology disclosed in this specification suppresses fatigue failure of the sterilization device caused by the cooling process. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a diagram schematically showing a sterilization apparatus according to a first embodiment. [Figure 2] FIG. 2 is a flowchart showing the operation of the sterilization apparatus according to the first embodiment. [Figure 3] FIG. 3 is a flowchart showing the cooling process according to the first embodiment. [Figure 4] FIG. 4 is a flowchart showing the cooling process according to the second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings, but the present disclosure is not limited to the embodiments. The components of the embodiments described below can be combined as appropriate. In addition, some components may not be used.

[0010] [First embodiment] A first embodiment will be described.

[0011] <Sterilizer> FIG. 1 is a schematic diagram of a sterilization apparatus 1 according to this embodiment. The sterilization apparatus 1 sterilizes an object to be sterilized using a sterilization gas. Examples of the sterilization gas include steam, ethylene oxide gas (EOG), and hydrogen peroxide. In this embodiment, the sterilization apparatus 1 is a steam sterilization apparatus that uses steam as the sterilization gas.

[0012] As shown in Figure 1, the sterilization apparatus 1 comprises an inner can 2, an outer can 3, a temperature sensor 6, a pressure sensor 7, a timer 8, a control device 9, an inner can steam supply unit 10, an outer can steam supply unit 20, a compressed air supply unit 30, an inner can drainage unit 40, an outer can drainage unit 50, an inner can exhaust unit 60, a pressure reduction unit 70, a pressure recovery unit 80, a cooling water supply unit 90, and a cooling water discharge unit 100.

[0013] The inner can 2 has an inner can space 4 in which the object to be sterilized is placed. The inner can space 4 is the internal space of the inner can 2. An entrance / exit is provided in a part of the inner can 2. The entrance / exit of the inner can 2 is opened and closed by a door (not shown). By opening the door, a user of the sterilization device 1 can load or unload the object to be sterilized into or from the inner can space 4 through the entrance / exit of the inner can 2.

[0014] The outer can 3 is disposed around the inner can 2 so that an outer can space 5 is formed between the outer can 3 and the inner can 2. The outer can space 5 is formed between the inner can 2 and the outer can 3.

[0015] The temperature sensor 6 detects the temperature of at least one of the sterilization target, the inner can 2, and the outer can 3. In this embodiment, the temperature sensor 6 includes a sterilization target temperature sensor 6A that detects the temperature of the sterilization target placed in the inner can space 4, an inner can temperature sensor 6B that detects the temperature of the inner can 2, and an outer can temperature sensor 6C that detects the temperature of the outer can 3.

[0016] The pressure sensor 7 detects the pressure in at least one of the inner can space 4 and the outer can space 5. In this embodiment, the pressure sensor 7 includes an inner can pressure sensor 7A that detects the pressure in the inner can space 4 and an outer can pressure sensor 7B that detects the pressure in the outer can space 5.

[0017] The timer 8 measures the time.

[0018] The control device 9 includes a computer system that controls the components of the sterilization device 1.

[0019] The inner can steam supply unit 10 supplies steam to the inner can space 4 during the sterilization process of the object to be sterilized. The inner can steam supply unit 10 functions as a sterilization gas supply unit that supplies sterilizing gas to the inner can space 4 during the sterilization process of the object to be sterilized. The inner can steam supply unit 10 has an inner can steam supply line 11 that connects a steam supply source (not shown) to the inner can space 4, an inner can pressure reducing valve 12 arranged on the inner can steam supply line 11, and an inner can steam supply valve 13 arranged on the inner can steam supply line 11. Steam from the steam supply source is supplied to the inner can space 4 via the inner can steam supply line 11. The control device 9 controls the inner can steam supply unit 10 to switch between supplying and stopping the supply of steam to the inner can space 4. The control device 9 can switch between supplying and stopping the supply of steam to the inner can space 4 by opening and closing the inner can steam supply valve 13.

[0020] The outer can steam supply unit 20 supplies steam to the outer can space 5 during the sterilization process of the object to be sterilized. The outer can steam supply unit 20 has an outer can steam supply line 21 connecting a steam supply source (not shown) and the outer can space 5, an outer can pressure reducing valve 22 arranged in the outer can steam supply line 21, and an outer can steam supply valve 23 arranged in the outer can steam supply line 21. Steam from the steam supply source is supplied to the outer can space 5 via the outer can steam supply line 21. The control device 9 controls the outer can steam supply unit 20 to switch between supplying and stopping the supply of steam to the outer can space 5. The control device 9 can switch between supplying and stopping the supply of steam to the outer can space 5 by opening and closing the outer can steam supply valve 23.

[0021] In this embodiment, the outer can steam supply line 21 is arranged so as to branch off from the inner can steam supply line 11. Note that the outer can steam supply line 21 does not have to branch off from the inner can steam supply line 11, and the outer can steam supply line 21 and the inner can steam supply line 11 may be separate steam supply lines. Steam, which is a sterilizing gas, is supplied to the outer can space 5. In this embodiment, steam at 121°C is supplied to each of the inner can space 4 and the outer can space 5. Note that the temperature of the steam supplied to each of the inner can space 4 and the outer can space 5 may be 135°C.

[0022] The compressed air supply unit 30 supplies compressed air to the inner can space 4 during the sterilization process of the sterilization target. The compressed air supply unit 30 includes an inner can pressurization line 31 connecting a compressed air supply source (not shown) and the inner can space 4, an air filter 32 arranged in the inner can pressurization line 31, an inner can pressurization valve 33 arranged in the inner can pressurization line 31, and a check valve 34 arranged in the inner can pressurization line 31. Steam from the compressed air supply source is supplied to the inner can space 4 via the inner can pressurization line 31. The control device 9 controls the compressed air supply unit 30 to switch between supplying and stopping the supply of compressed air to the inner can space 4. The control device 9 can switch between supplying and stopping the supply of compressed air to the inner can space 4 by opening and closing the inner can pressurization valve 33. When pressurizing the inner can space 4, the control device 9 controls the compressed air supply unit 30 so that compressed air is supplied to the inner can space 4.

[0023] When the object to be sterilized is a bottle, the inside of the bottle is sealed, so if high-temperature steam is supplied to the inner can space 4 during the sterilization process, the bottle may expand and deform. By pressurizing the inner can space 4 with the compressed air supply unit 30, expansion and deformation of the bottle is suppressed.

[0024] The inner can drainage unit 40 discharges water (drain) generated in the inner can space 4 from the inner can space 4. The inner can drainage unit 40 has an inner can drainage line 41 connected to the inner can space 4, and a steam trap 42 and a check valve 43 arranged in the inner can drainage line 41. The water generated in the inner can space 4 is discharged from the inner can space 4 via the inner can drainage line 41.

[0025] The outer can drainage unit 50 discharges water (drainage) generated in the outer can space 5 from the outer can space 5. The outer can drainage unit 50 has an outer can drainage line 51 connected to the outer can space 5, a bypass line 52 for the outer can drainage line 51, a steam trap shut-off valve 53, a steam trap 54, and a check valve 55 arranged in the outer can drainage line 51, and an outer can drainage valve 56 and a check valve 57 arranged in the bypass line 52. The drainage generated in the outer can space 5 is discharged from the outer can space 5 via at least one of the outer can drainage line 51 and the bypass line 52.

[0026] The inner can exhaust unit 60 exhausts gas from the inner can space 4. The inner can exhaust unit 60 has an inner can exhaust line 61 connected to the inner can space 4, and an inner can exhaust valve 62 and a check valve 63 arranged in the inner can exhaust line 61. Gas in the inner can space 4 is exhausted from the inner can space 4 via the inner can exhaust line 61. By supplying steam to the inner can space 4 with the inner can exhaust valve 62 open, the gas in the inner can space 4 is expelled from the inner can space 4 via at least a part of the inner can drain line 41 and the inner can exhaust line 61.

[0027] The decompression unit 70 exhausts gas from the inner can space 4 to reduce the pressure of the inner can space 4. The decompression unit 70 has a vacuum line 71 connected to the inner can space 4, and a vacuum valve 72, a check valve 73, and a vacuum pump 74 arranged in the vacuum line 71. When the vacuum pump 74 is driven, the gas in the inner can space 4 is sucked by the vacuum pump 74 and exhausted from the inner can space 4 via the vacuum line 71. The control device 9 controls the decompression unit 70 to switch between reducing the pressure of the inner can space 4 and stopping the pressure reduction. The control device 9 switches between driving and stopping the driving of the vacuum pump 74 to switch between reducing the pressure of the inner can space 4 and stopping the pressure reduction.

[0028] The pressure-recovery unit 80 supplies outside air to the depressurized inner can space 4 to restore the pressure in the inner can space 4. The pressure-recovery unit 80 has an air supply line 81 connected to the inner can space 4, and a sterile filter 82, a check valve 83, and an air supply valve 84 arranged in the air supply line 81. The control device 9 can supply outside air to the inner can space 4 via the air supply line 81 by opening the air supply valve 84 when the inner can space 4 is depressurized. The inner can space 4 is restored to pressure by supplying outside air to the inner can space 4 via the air supply line 81.

[0029] In the cooling process after the sterilization process, the cooling water supply unit 90 supplies cooling water at a first temperature lower than the sterilization temperature of the object to be sterilized to the outer can space 5, and then supplies cooling water at a second temperature lower than the first temperature to the outer can space 5. In the following description, the cooling water at the first temperature will be referred to as "first cooling water" as appropriate, and the cooling water at the second temperature will be referred to as "second cooling water" as appropriate.

[0030] The cooling water supply unit 90 has a cooling water supply line 91 that connects a cooling water supply source (not shown) and the outer can space 5, a water supply valve 92 arranged in the cooling water supply line 91, and a heating section 93 arranged in the cooling water supply line 91. The cooling water supply source supplies cooling water at a second temperature (second cooling water). The second temperature is higher than 0°C. The second temperature is room temperature. The second temperature is, for example, not lower than 10°C and not higher than 20°C.

[0031] The heating unit 93 heats the cooling water (second cooling water) at a second temperature supplied from the cooling water supply source to generate the cooling water (first cooling water) at a first temperature. In this embodiment, the heating unit 93 heats the second cooling water with steam, which is a sterilizing gas, to generate the first cooling water.

[0032] The heating section 93 is connected to the outer can steam supply line 21 via a steam supply line 24. The steam supply line 24 is arranged to branch off from the outer can steam supply line 21. Steam is supplied to the heating section 93 from a steam supply source via the outer can steam supply line 21 and the steam supply line 24. A steam supply valve 94 is arranged on the steam supply line 24. The control device 9 can supply each of the second cooling water and steam to the heating section 93 by opening the steam supply valve 94 while the water supply valve 92 is open. In the heating section 93, the second cooling water at the second temperature is heated by the steam to become the first cooling water at the first temperature. The first cooling water produced in the heating section 93 is supplied to the outer can space 5.

[0033] The heating unit 93 generates the first cooling water by mixing the second cooling water with steam. The heating unit 93 may be a mixing valve that mixes the second cooling water with steam. The heating unit 93 may also generate the first cooling water by exchanging heat between the second cooling water and steam. The heating unit 93 may also be an indirect heat exchanger that exchanges heat between the second cooling water and steam.

[0034] The control device 9 can supply second cooling water to the heating section 93 and stop the supply of steam to the heating section 93 by closing the steam supply valve 94 while keeping the water supply valve 92 open. When the supply of steam to the heating section 93 is stopped, the second cooling water is not heated and is therefore supplied to the outer can space 5.

[0035] That is, when the control device 9 supplies first cooling water at a first temperature to the outer can space 5 via the cooling water supply line 91, it heats the second cooling water flowing through the cooling water supply line 91 with steam. When the control device 9 supplies second cooling water at a second temperature to the outer can space 5 via the cooling water supply line 91, it stops heating the second cooling water flowing through the cooling water supply line 91 with steam.

[0036] In this embodiment, a temperature sensor 95 that detects the temperature of the cooling water (first cooling water or second cooling water) supplied to the outer can space 5 is arranged downstream of the heating section 93 in the cooling water supply line 91. Based on the detection data of the temperature sensor 95, the control device 9 controls the steam supply valve 94 to control the flow rate of steam supplied to the heating section 93 so that the first cooling water reaches a target temperature. By adjusting the flow rate of steam supplied to the heating section 93, the first temperature of the first cooling water is adjusted.

[0037] The cooling water discharge unit 100 discharges the cooling water (first cooling water or second cooling water) supplied to the outer can space 5 from the top of the outer can space 5. The cooling water discharge unit 100 has a drain line 101 connected to the top of the outer can space 5, and an overflow valve 102 and a check valve 103 arranged in the drain line 101. The cooling water supplied to the outer can space 5 is discharged from the outer can space 5 via the drain line 101. At least a portion of the cooling water supplied to the outer can space 5 overflows from the top of the outer can 3 via the drain line 101 connected to the top of the outer can space 5.

[0038] <Operation> Figure 2 is a flowchart showing the operation of the sterilization apparatus 1 according to this embodiment. The sterilization apparatus 1 carries out a sterilization process SA to sterilize the sterilization target placed in the inner can space 4, and a cooling process SB to cool at least a part of the sterilization apparatus 1. The cooling process SB is carried out after the sterilization process SA is completed.

[0039] After the object to be sterilized is placed in the inner can space 4, and before the sterilization process SA is started, steam is supplied to the outer can space 5 by the outer can steam supply unit 20. As described above, steam at 121°C is supplied to the outer can space 5. By supplying steam to the outer can space 5, the temperature of the outer can space 5 rises. Based on the detection data of the outer can pressure sensor 7B, the control device 9 controls the supply of steam by the outer can steam supply unit 20 so that the outer can space 5 maintains a constant pressure. Water (drainage) produced in the outer can space 5 is discharged from the outer can space 5 by the outer can drainage unit 50.

[0040] After the outer can space 5 is filled with steam, dynamic replacement is performed in which air is removed from the inner can space 4 by supplying steam to the inner can space 4. When dynamic replacement is performed, the control device 9 supplies steam to the inner can space 4 using the inner can steam supply unit 10 while stopping the decompression by the decompression unit 70. This causes gas in the inner can space 4 to be discharged from the inner can space 4 via the inner can exhaust unit 60. The control device 9 supplies steam to the inner can space 4 and pushes air out of the inner can space 4 by opening the inner can steam supply valve 13 while keeping the inner can exhaust valve 62 open. After the supply of steam by the inner can steam supply unit 10 and the discharge of gas by the inner can exhaust unit 60 have ended, vacuum replacement is performed in which air is removed from the inner can space 4 by decompressing the inner can space 4 using the decompression unit 70. When vacuum replacement is performed, the control device 9 can decompress the inner can space 4 by opening the vacuum valve 72 while keeping the inner can steam supply valve 13 and the inner can exhaust valve 62 closed. After the decompression by the decompression unit 70 is completed, the control device 9 supplies steam to the internal can space 4 by the internal can steam supply unit 10. After the internal can steam supply unit 10 supplies steam to the internal can space 4 until the internal can space 4 reaches atmospheric pressure, the internal can space 4 is decompressed by the decompression unit 70. By repeating the decompression of the internal can space 4 and the supply of steam to the internal can space 4 multiple times, air is removed from the internal can space 4.

[0041] As described above, in this embodiment, vacuum replacement is performed after dynamic replacement. Dynamic replacement may be performed without vacuum replacement. Vacuum replacement may be performed without dynamic replacement.

[0042] After the air has been removed from the inner can space 4, the sterilization process SA of the sterilization object is started. With the decompression by the decompression unit 70 stopped, steam is supplied to the inner can space 4 by the inner can steam supply unit 10. Steam at 121°C is supplied to the inner can space 4. Based on the detection data of the inner can temperature sensor 6B, the control device 9 controls the supply of steam by the inner can steam supply unit 10 so that the inner can space 4 is maintained at the specified sterilization temperature for the specified sterilization time. In this embodiment, the sterilization temperature is 121°C. The inner can space 4, in which the sterilization object is placed, is filled with steam at the sterilization temperature, thereby sterilizing the sterilization object.

[0043] After the sterilization process SA of the sterilization object is completed, the sterilization object is dried, and then the cooling process SB is started. In the drying process of the sterilization object, the supply of steam by the inner can steam supply unit 10 is stopped, and gas is exhausted from the inner can space 4 by the inner can exhaust unit 60. The control device 9 can exhaust steam from the inner can space 4 by opening the inner can exhaust valve 62 with the inner can steam supply valve 13 closed. After steam is exhausted from the inner can space 4, the inner can space 4 is depressurized by the depressurization unit 70. The sterilization object is dried by depressurizing the inner can space 4. Note that the drying process may be omitted.

[0044] 3 is a flowchart showing the cooling process SB according to this embodiment. The control device 9 controls the cooling water supply unit 90 so that first cooling water at a first temperature is supplied to the outer can space 5 (step SB11).

[0045] The first temperature is lower than the sterilization temperature. In this embodiment, the first temperature is equal to or higher than the sterilization temperature minus 100°C. When the sterilization temperature is 121°C, the first temperature is set to 21°C or higher. If the first temperature is too high, the cooling effect may be insufficient. In this embodiment, the first temperature is set to 21°C or higher and 60°C or lower. When the sterilization temperature is 135°C, the first temperature may be set to, for example, 35°C or higher and 70°C or lower.

[0046] When supplying first cooling water at a first temperature to the outer can space 5, the control device 9 opens the steam supply valve 94 while keeping the water supply valve 92 open. As a result, cooling water (second cooling water) from the cooling water supply source is supplied to the heating section 93 via the cooling water supply line 91, and steam from the steam supply source is supplied to the heating section 93 via the outer can steam supply line 21 and the steam supply line 24. In the heating section 93, the cooling water (second cooling water) supplied from the cooling water supply source is heated by the steam to become first cooling water at the first temperature. The control device 9 controls the steam supply valve 94 to adjust the flow rate of steam supplied to the heating section 93 so that the first temperature is a set temperature of 21°C or higher and 60°C or lower. The first cooling water produced in the heating section 93 is supplied to the outer can space 5.

[0047] The cooling water supply unit 90 supplies first cooling water to the outer can space 5, filling the outer can space 5 with the first cooling water. At least a portion of the first cooling water supplied to the outer can space 5 is discharged from the outer can space 5 via the cooling water discharge unit 100. The cooling water discharge unit 100 causes the first cooling water to overflow from the top of the outer can 3. Because the first cooling water overflows from the top of the outer can 3, the first cooling water comes into contact with almost the entire outer surface of the inner can 2, and the first cooling water comes into contact with almost the entire inner surface of the outer can 3. This allows the inner can 2 and the outer can 3 to be efficiently cooled by the first cooling water.

[0048] Based on the detection data of the temperature sensor 6, the control device 9 determines whether the supply of the first cooling water has caused the temperature of at least one of the sterilization object, the inner can 2, and the outer can 3 to fall below a set value (step SB12).

[0049] The set point is a predetermined value that is lower than the sterilization temperature. In this embodiment, the set point is 100°C.

[0050] The temperature of the member may be the temperature of the object to be sterilized, the temperature of the inner can 2, or the temperature of the outer can 3. In this embodiment, in step SB12, the control device 9 determines, based on the detection data of the outer can temperature sensor 6C, whether or not the supply of the first cooling water has caused the temperature of the outer can 3 to become equal to or lower than a set value.

[0051] In step SB12, if it is determined that the temperature of the outer can 3 is not equal to or lower than the set value (step SB12: No), the control device 9 continues supplying the first cooling water to the outer can space 5. At least a portion of the first cooling water supplied to the outer can space 5 overflows from the upper part of the outer can 3. In parallel with the supply of the first cooling water from the cooling water supply unit 90, the first cooling water is discharged from the cooling water discharge unit 100.

[0052] In step SB12, if it is determined that the temperature of the outer can 3 has become lower than the set value (step SB12: Yes), the control device 9 controls the cooling water supply unit 90 to switch from supplying the first cooling water to supplying the second cooling water (step SB13).

[0053] The second temperature is lower than the first temperature. The control device 9 can stop the supply of steam to the heating unit 93 by closing the steam supply valve 94 while keeping the water supply valve 92 open. When the supply of steam to the heating unit 93 is stopped, the second cooling water is not heated and is therefore supplied to the outer can space 5.

[0054] The second cooling water is supplied to the outer can space 5 by the cooling water supply unit 90, thereby replacing the first cooling water in the outer can space 5 with the second cooling water. At least a portion of the second cooling water supplied to the outer can space 5 is discharged from the outer can space 5 via the cooling water discharge unit 100. The second cooling water overflows from the top of the outer can 3 by the cooling water discharge unit 100. Because the second cooling water overflows from the top of the outer can 3, the second cooling water comes into contact with almost the entire outer surface of the inner can 2, and the second cooling water comes into contact with almost the entire inner surface of the outer can 3. This allows the inner can 2 and the outer can 3 to be efficiently cooled by the second cooling water.

[0055] When the control device 9 determines, based on the detection data of the outer can temperature sensor 6C, that the temperature of the outer can 3 has reached the target cooling temperature value, the control device 9 ends the cooling process SB. The target cooling temperature value is, for example, 40°C. After the cooling process SB is completed, the user of the sterilization apparatus 1 can open the door and remove the items to be sterilized from the inner can space 4.

[0056] <Effects> As described above, the sterilization apparatus 1 comprises an inner can 2 having an inner can space 4 in which the object to be sterilized is placed, an outer can 3 arranged around the inner can 2 so that an outer can space 5 is formed between the inner can 2 and the outer can 3, an inner can steam supply unit 10 (sterilization gas supply unit) that supplies steam, which is a sterilization gas, to the inner can space 4 in the sterilization process SA of the object to be sterilized, and a cooling water supply unit 90 that supplies first cooling water at a first temperature lower than the sterilization temperature of the object to be sterilized to the outer can space 5, and then supplies second cooling water at a second temperature lower than the first temperature to the outer can space 5 in the cooling process SB after the sterilization process SA.

[0057] In this embodiment, rapid cooling of the sterilization apparatus 1 during the cooling process SB following the sterilization process SA is prevented, thereby preventing fatigue damage to the sterilization apparatus 1 caused by the cooling process SB. If low-temperature cooling water (e.g., water below 10°C) is supplied all at once to the outer can space 5 after the sterilization process SA is completed, the components of the sterilization apparatus 1, such as the inner can 2 or the outer can 3, which have reached a high temperature during the sterilization process SA, will be rapidly cooled. Repeated rapid temperature changes could cause fatigue damage to the components of the sterilization apparatus 1. In this embodiment, after the sterilization process SA is completed, first cooling water at a first temperature is supplied to the outer can space 5, thereby gradually cooling the components of the sterilization apparatus 1. This prevents fatigue damage to the components of the sterilization apparatus 1. After the temperature of the components of the sterilization apparatus 1 is reached by the first cooling water, second cooling water at a second temperature is supplied to the outer can space 5, thereby cooling the components of the sterilization apparatus 1 to the target cooling temperature. The use of low-temperature second cooling water allows the components of the sterilization apparatus 1 to be cooled efficiently.

[0058] Furthermore, when the object to be sterilized is a bottle, the inside of the bottle is sealed, so if low-temperature cooling water is supplied all at once to the outer can space 5 in the cooling process after the sterilization process SA is completed, the bottle may be deformed due to the sudden temperature change. In this embodiment, sudden temperature changes are suppressed in the cooling process SB, so deformation of the bottle is suppressed.

[0059] In this embodiment, the first temperature of the first cooling water is equal to or higher than the sterilization temperature minus 100° C. This prevents the members of the sterilization apparatus 1 from being cooled suddenly in the cooling treatment SB.

[0060] The cooling water supply unit 90 generates the first cooling water by heating the cooling water (second cooling water) supplied from the cooling water supply source, thereby easily generating the first cooling water.

[0061] The cooling water supply unit 90 heats the cooling water (second cooling water) supplied from the cooling water supply source by using steam, which is a sterilizing gas, thereby reducing the cost required to heat the first cooling water.

[0062] The cooling water supply unit 90 has a cooling water supply line 91 connected to the outer can space 5. When supplying the first cooling water to the outer can space 5 via the cooling water supply line 91, the cooling water supply unit 90 heats the second cooling water flowing through the cooling water supply line 91 with steam. When supplying the second cooling water to the outer can space 5 via the cooling water supply line 91, the cooling water supply unit 90 stops heating the second cooling water flowing through the cooling water supply line 91 with steam. The control device 9 can switch between supplying the first cooling water and supplying the second cooling water to the outer can space 5 simply by switching between supplying and stopping steam to the heating section 93.

[0063] [Second embodiment] A second embodiment will be described. In the first embodiment described above, the control device 9 controls the cooling water supply unit 90 to switch from supplying the first cooling water to supplying the second cooling water based on the detection data of the temperature sensor 6. In the present embodiment, an example will be described in which the control device 9 controls the cooling water supply unit 90 to switch from supplying the first cooling water to supplying the second cooling water based on the measurement data of the timer 8.

[0064] 4 is a flowchart showing the cooling process SB according to this embodiment. The control device 9 controls the cooling water supply unit 90 so that first cooling water at a first temperature is supplied to the outer can space 5 (step SB21).

[0065] The cooling water supply unit 90 supplies the first cooling water to the outer can space 5, thereby filling the outer can space 5 with the first cooling water. At least a portion of the first cooling water supplied to the outer can space 5 overflows from the upper part of the outer can space 5 via the cooling water discharge unit 100.

[0066] The timer 8 measures the time during which the first cooling water is supplied to the outer can space 5. The control device 9 determines, based on the measurement data of the timer 8, whether the time during which the first cooling water is supplied to the outer can space 5 has reached or exceeded a set value (step SB22).

[0067] The set value is a predetermined value, and in this embodiment, the set value is 5 minutes.

[0068] In step SB22, if it is determined that the time during which the first cooling water is supplied to the outer can space 5 is not equal to or longer than the set value (step SB22: No), the control device 9 continues to supply the first cooling water to the outer can space 5. At least a portion of the first cooling water supplied to the outer can space 5 overflows from the upper part of the outer can 3.

[0069] In step SB22, if it is determined that the time during which the first cooling water is supplied to the outer can space 5 has exceeded the set value (step SB22: Yes), the control device 9 controls the cooling water supply unit 90 to switch from supplying the first cooling water to supplying the second cooling water (step SB23).

[0070] The cooling water supply unit 90 supplies the second cooling water to the outer can space 5, thereby replacing the first cooling water with the second cooling water in the outer can space 5. At least a portion of the second cooling water supplied to the outer can space 5 overflows from the top of the outer can 3 by the cooling water discharge unit 100.

[0071] When the control device 9 determines based on the measurement data of the timer 8 that the time during which the second cooling water is supplied to the outer can space 5 reaches the cooling time target value, it ends the cooling process SB.

[0072] As explained above, in this embodiment as well, fatigue failure of the members of the sterilization apparatus 1 caused by the cooling process SB is suppressed.

[0073] [Other embodiments] In the above-described embodiment, in the cooling process SB, first cooling water at a first temperature is supplied to the outer can space 5, and then second cooling water at a second temperature is supplied. That is, the temperature of the cooling water supplied to the outer can space 5 is changed in two stages. The temperature of the cooling water supplied to the outer can space 5 may be changed in any multiple stages, such as three or more stages. When the temperature of the cooling water supplied to the outer can space 5 is changed in multiple stages, the cooling water supplied to the outer can space 5 is adjusted so that the temperature is lower in the later stages.

[0074] In the above-described embodiment, the sterilization apparatus 1 is a steam sterilization apparatus that uses steam as a sterilization gas. The sterilization apparatus 1 may be an EOG sterilization apparatus that uses ethylene oxide gas (EOG) as a sterilization gas, or a hydrogen peroxide sterilization apparatus that uses hydrogen peroxide as a sterilization gas. [Explanation of symbols]

[0075] 1...sterilization equipment, 2...inner can, 3...outer can, 4...inner can space, 5...outer can space, 6...temperature sensor, 6A...sterilization target temperature sensor, 6B...inner can temperature sensor, 6C...outer can temperature sensor, 7...pressure sensor, 7A...inner can pressure sensor, 7B...outer can pressure sensor, 8...timer, 9...control device, 10...inner can steam supply unit (sterilization gas supply unit), 11...inner can steam supply line, 12...inner can pressure reducing valve, 13...inner can steam supply valve, 20...outer can steam supply unit, 21...outer can steam supply line, 22...outer can pressure reducing valve, 23...outer can steam supply valve, 24...steam supply line, 30...compressed air supply unit, 31...inner can pressure line, 32...air filter, 33...inner can pressure valve, 34...check valve, 40...inner can drainage unit, 41...inner can drainage line, 42...steam trap, 43... Check valve, 50...outer can drainage unit, 51...outer can drainage line, 52...bypass line, 53...steam trap shut-off valve, 54...steam trap, 55...check valve, 56...outer can drainage valve, 57...check valve, 60...inner can exhaust unit, 61...inner can exhaust line, 62...inner can exhaust valve, 63...check valve, 70...pressure reduction unit, 71...vacuum line, 72...vacuum valve, 73...check valve, 74...vacuum pump, 80...pressure recovery unit, 81...air supply line, 82...sterile filter, 83...check valve, 84...air supply valve, 90...cooling water supply unit, 91...cooling water supply line, 92...water supply valve, 93...heating section, 94...steam supply valve, 95...temperature sensor, 100...cooling water discharge unit, 101...drainage line, 102...overflow valve, 103...check valve.

Claims

1. an inner can having an inner can space in which an object to be sterilized is placed; an outer can disposed around the inner can such that an outer can space is formed between the inner can and the outer can; a sterilization gas supply unit for supplying sterilization gas to the inner can space during sterilization of the object to be sterilized; a cooling water supply unit that supplies first cooling water at a first temperature lower than the sterilization temperature of the object to be sterilized to the outer can space, and then supplies second cooling water at a second temperature lower than the first temperature to the outer can space, in order to suppress fatigue failure of components of the sterilization apparatus during the cooling process after the sterilization process. Sterilization equipment.

2. a temperature sensor for detecting the temperature of at least one of the object to be sterilized, the inner can, and the outer can; a control device that controls the cooling water supply unit to switch from supplying the first cooling water to supplying the second cooling water when it is determined based on detection data from the temperature sensor that the temperature of the member has become equal to or lower than a set value due to the supply of the first cooling water.

10. The sterilization device of claim 1.

3. a timer that measures a time during which the first cooling water is supplied to the outer can space; a control device that controls the cooling water supply unit to switch from supplying the first cooling water to supplying the second cooling water when it is determined based on measurement data of the timer that the time for which the first cooling water is supplied has reached a set value or more.

10. The sterilization device of claim 1.

4. The first temperature is equal to or greater than the sterilization temperature minus 100°C.

10. The sterilization device of claim 1.

5. The cooling water supply unit heats the second cooling water to generate the first cooling water.

10. The sterilization device of claim 1.

6. The cooling water supply unit heats the second cooling water with the sterilization gas.

6. The sterilization apparatus according to claim 5.

7. the cooling water supply unit has a cooling water supply line connected to the outer can space, When the first cooling water is supplied to the outer can space through the cooling water supply line, the second cooling water flowing through the cooling water supply line is heated by the sterilization gas; When the second cooling water is supplied to the outer can space through the cooling water supply line, heating of the second cooling water flowing through the cooling water supply line by the sterilization gas is stopped.

7. The sterilization apparatus according to claim 6.

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