Steam sterilizer / sterilizer controller

Abstract

To appropriately operate a steam sterilization / pasteurization device.SOLUTION: A controller 6 for a steam sterilization / pasteurization device 5 includes: an activation signal receiving section 61 that receives an activation signal to activate a first steam sterilization / pasteurization device 51 using steam supplied from a boiler 2; and a standby command section 64 that outputs a standby command to pend execution of predetermined processing of the first steam sterilization / pasteurization device 51 if the activation signal is received and a determination is made that steam supplied from the boiler 2 to the first steam sterilization / pasteurization device 51 is in short supply.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present disclosure relates to a controller for a steam sterilizer and bactericidal device.

Background Art

[0002] In the technical field related to steam sterilizers and bactericidal devices, sterilization equipment as disclosed in Patent Document 1 is known.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the operation of a steam sterilizer and bactericidal device, steam supplied from a boiler to the steam sterilizer and bactericidal device is used. When starting another steam sterilizer and bactericidal device during the operation of a certain steam sterilizer and bactericidal device, there is a possibility that the steam supplied from the boiler to the steam sterilizer and bactericidal device will be insufficient. Due to the insufficient steam supplied from the boiler to the steam sterilizer and bactericidal device, if the operation of the steam sterilizer and bactericidal device is interrupted, the sterilization and disinfection target will not be sterilized and disinfected. If, for example, a large number of boilers are constantly operated so that the insufficient steam supplied from the boiler to the steam sterilizer and bactericidal device does not occur, the boilers will consume energy unnecessarily.

[0005] An object of the present disclosure is to properly operate a steam sterilizer and bactericidal device.

Means for Solving the Problems

[0006] A controller for a steam sterilizer is provided, comprising: a start signal receiving unit that receives a start signal to start a first steam sterilizer that uses steam supplied from a boiler; and a standby command unit that, upon receiving a start signal and determining that there is insufficient steam supplied from the boiler to the first steam sterilizer, outputs a standby command to cause the first steam sterilizer to wait before performing a predetermined process. [Effects of the Invention]

[0007] According to this disclosure, the steam sterilizer / sterilizer will be operated properly. [Brief explanation of the drawing]

[0008] [Figure 1] Figure 1 is a schematic diagram showing a steam system according to an embodiment. [Figure 2] Figure 2 is a schematic diagram showing a steam sterilizer according to an embodiment. [Figure 3] Figure 3 is a flowchart showing the operation of the steam sterilizer according to the embodiment. [Figure 4] Figure 4 is a block diagram of a controller according to an embodiment. [Figure 5] Figure 5 is a diagram illustrating the determination method by the standby command unit according to this embodiment. [Figure 6] Figure 6 is a flowchart showing the steam sterilization method according to the embodiment. [Figure 7] Figure 7 is a schematic diagram showing a steam system according to another embodiment. [Modes for carrying out the invention]

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

[0010] [Steam System] Figure 1 is a schematic diagram showing a steam system 1 according to an embodiment. As shown in Figure 1, the steam system 1 comprises a boiler 2, a header 3, a pressure sensor 4, a steam sterilizer 5, and a controller 6.

[0011] Boiler 2 generates steam. In this embodiment, multiple boilers 2 are provided. For the sake of simplicity in the drawings, only one boiler 2 is shown in Figure 1. In this embodiment, boiler 2 is a fuel boiler that uses fuel as a heat source. Boiler 2 may also be an electric boiler that uses electricity as a heat source.

[0012] Header 3 is a container that receives steam from boiler 2. Header 3 is connected to boiler 2. Steam generated from boiler 2 is supplied to header 3. Steam generated from boiler 2 is collected in header 3.

[0013] The pressure sensor 4 detects the header pressure, which indicates the pressure of the steam contained in the header 3. The pressure sensor 4 is installed in the header 3.

[0014] The steam sterilizer 5 sterilizes the items to be sterilized using steam supplied from the boiler 2. In this embodiment, multiple steam sterilizers 5 are provided. The steam sterilizers 5 are connected to the header 3. The steam sterilizers 5 use steam supplied from the header 3.

[0015] Controller 6 controls the steam sterilizer 5. Controller 6 is provided for each of the multiple steam sterilizers 5. Controller 6 includes a computer system. Multiple controllers 6 are interconnected. Multiple controllers 6 can communicate with each other. Of the controllers 6 provided for each of the multiple steam sterilizers 5, one controller 6 can control all of them on behalf of the others, or multiple controllers 6 can cooperate to control all of them.

[0016] [Steam sterilizer] FIG. 2 is a diagram schematically showing a steam sterilizer 5 according to an embodiment. As shown in FIG. 2, the steam sterilizer 5 includes a chamber 8, a jacket 9, a jacket steam supply device 10, a jacket drain discharge device 11, a jacket exhaust device 12, a pressure reducing device 13, a pressure restoring device 14, a chamber steam supply device 15, a chamber drain discharge device 16, a chamber exhaust device 17, a jacket pressure sensor 18A, a chamber pressure sensor 18B, a jacket temperature sensor 20A, and a chamber temperature sensor 20B.

[0017] The chamber 8 has a processing space 21 in which a sterilization target is accommodated. The processing space 21 is the internal space of the chamber 8. An entrance / exit is provided in a part of the chamber 8. The entrance / exit of the chamber 8 is opened and closed by a door (not shown). A user of the steam system 1 can carry a sterilization target into the processing space 21 or carry a sterilization target out of the processing space 21 through the entrance / exit of the chamber 8 by opening the door.

[0018] The jacket 9 is arranged around the chamber 8. The jacket 9 forms a jacket space 22 between the jacket 9 and the chamber 8.

[0019] The jacket steam supply device 10 supplies steam to the jacket space 22 of the jacket 9. The jacket steam supply device 10 has a jacket steam supply line 23 connecting the header 3 and the jacket space 22, and a jacket steam supply valve 24 arranged on the jacket steam supply line 23. Steam from the header 3 is supplied to the jacket space 22 through the jacket steam supply line 23. The jacket steam supply device 10 can switch between supplying steam to the jacket space 22 and stopping the supply. By opening and closing the jacket steam supply valve 24, the supply and the supply stop of steam to the jacket space 22 are switched.

[0020] The jacket drain discharge device 11 discharges the drain generated in the jacket space 22 from the jacket space 22. The jacket drain discharge device 11 includes a jacket drain discharge line 25 connected to the jacket space 22, and a steam trap 26 and a check valve 27 located in the jacket drain discharge line 25. The drain generated in the jacket space 22 is discharged from the jacket space 22 via the jacket drain discharge line 25.

[0021] The jacket exhaust device 12 discharges gas from the jacket space 22 of the jacket 9. The jacket exhaust device 12 includes a jacket exhaust line 28 connected to the jacket space 22, and a jacket exhaust valve 29 and a check valve 30 located in the jacket exhaust line 28. The gas in the jacket space 22 is discharged from the jacket space 22 via the jacket exhaust line 28. When steam is supplied to the jacket space 22 with the jacket exhaust valve 29 open, the gas in the jacket space 22 is expelled from the jacket space 22 via the jacket exhaust line 28. In this embodiment, the jacket exhaust valve 29 is a temperature control valve that opens and closes based on the temperature of the gas passing through the jacket exhaust valve 29. The jacket exhaust valve 29 closes when the temperature of the gas passing through the jacket exhaust valve 29 exceeds the operating temperature.

[0022] The depressurization device 13 reduces the pressure in the processing space 21 of the chamber 8 by discharging gas from the processing space 21. The depressurization device 13 includes a vacuum line 31 connected to the processing space 21, and a vacuum valve 32, a vacuum pump 33, and a check valve 34 arranged in the vacuum line 31. When the vacuum pump 33 is driven, the gas in the processing space 21 is sucked in by the vacuum pump 33 and discharged from the processing space 21 via the vacuum line 31. The depressurization device 13 can switch between reducing the pressure in the processing space 21 and stopping the pressure reduction. By switching between driving and stopping the vacuum pump 33, the pressure reduction in the processing space 21 is switched between reducing the pressure and stopping the pressure reduction.

[0023] The repressurization device 14 repressurizes the processing space 21 of the depressurized chamber 8 by supplying outside air to it. The repressurization device 14 has an air supply line 35 connected to the processing space 21, and a sterile filter 36, an air supply valve 37, and a check valve 38 arranged in the air supply line 35. By opening the air supply valve 37 when the processing space 21 is depressurized, outside air is supplied to the processing space 21 via the air supply line 35. The processing space 21 is repressurized by the supply of outside air to the processing space 21 via the air supply line 35.

[0024] The chamber steam feed device 15 supplies steam to the processing space 21 of the chamber 8. The chamber steam feed device 15 has a chamber steam feed line 39 connecting the header 3 and the processing space 21, and a chamber steam feed valve 40 located in the chamber steam feed line 39. Steam from the header 3 is supplied to the processing space 21 via the chamber steam feed line 39. The chamber steam feed device 15 can switch between supplying and stopping steam to the processing space 21. The supply and stopping of steam to the processing space 21 is switched by opening and closing the chamber steam feed valve 40.

[0025] The chamber drain discharge device 16 discharges the drain generated in the processing space 21 from the processing space 21. The chamber drain discharge device 16 has a chamber drain discharge line 41 connected to the processing space 21, and a steam trap 42 and a check valve 43 located in the chamber drain discharge line 41. The drain generated in the processing space 21 is discharged from the processing space 21 via the chamber drain discharge line 41.

[0026] The chamber exhaust device 17 discharges gas from the processing space 21 of the chamber 8. The chamber exhaust device 17 has a chamber exhaust line 44 connected to the processing space 21 via at least a portion of the chamber drain discharge line 41, and a chamber exhaust valve 45 and a check valve 46 located in the chamber exhaust line 44. The gas in the processing space 21 is discharged from the processing space 21 via at least a portion of the chamber drain discharge line 41 and the chamber exhaust line 44. When steam is supplied to the processing space 21 with the chamber exhaust valve 45 open, the gas in the processing space 21 is expelled from the processing space 21 via at least a portion of the chamber drain discharge line 41 and the chamber exhaust line 44.

[0027] The downstream end of the vacuum line 31, the downstream end of the jacket exhaust line 28, and the downstream end of the chamber exhaust line 44 are each connected to the first section 41A of the chamber drain discharge line 41. The downstream end of the jacket drain discharge line 25 is connected to the second section 41B of the chamber drain discharge line 41. The first section 41A is defined downstream of the check valve 43. The second section 41B is defined downstream of the first section 41A. A check valve 47 is located in the chamber drain discharge line 41 between the first section 41A and the second section 41B.

[0028] The jacket pressure sensor 18A detects the pressure in the jacket space 22 of the jacket 9.

[0029] The chamber pressure sensor 18B detects the pressure in the processing space 21 of the chamber 8.

[0030] The jacket temperature sensor 20A detects the temperature of the jacket space 22 of the jacket 9.

[0031] The chamber temperature sensor 20B detects the temperature of the processing space 21 of the chamber 8.

[0032] [Steam sterilizer operation] Figure 3 is a flowchart illustrating the operation of the steam sterilizer 5 according to this embodiment. The steam sterilizer 5 has a start switch that is operated to start the steam sterilizer 5. The start switch is operated by the user of the steam sterilizer 5. When the start switch is operated, the steam sterilizer 5 is started and operation of the steam sterilizer 5 begins.

[0033] The steam sterilizer 5 performs preheating (step SA1), air discharge (step SA2), sterilization (step SA3), steam discharge (step SA4), and drying / cooling (step SA5).

[0034] Preheating (step SA1) refers to the process of preheating the chamber 8 by introducing steam supplied from the boiler 2 into the jacket space 22 of the jacket 9. In the preheating process, the jacket steam feed device 10 supplies steam to the jacket space 22 of the jacket 9. Steam from the header 3 is supplied to the jacket space 22 via the jacket steam feed line 23.

[0035] During the preheating process, the air in the jacket space 22 is replaced with steam. When replacing the air in the jacket space 22 with steam, steam is supplied to the jacket space 22 by the jacket steam supply device 10, and the gas is discharged from the jacket space 22 by the jacket exhaust device 12. In this embodiment, the jacket steam supply valve 24 opens with the jacket exhaust valve 29 open, supplying steam to the jacket space 22 and pushing out the air. The supply of steam to the jacket space 22 causes the temperature of the jacket space 22 to rise. The temperature of the gas passing through the jacket exhaust valve 29 also rises. When the temperature of the gas passing through the jacket exhaust valve 29 exceeds the operating temperature, the jacket exhaust valve 29 closes. The closing of the jacket exhaust valve 29 stops the discharge of gas from the jacket space 22 by the jacket exhaust device 12. With the discharge of gas from the jacket space 22 stopped, steam is supplied to the jacket space 22 by the jacket steam supply device 10. Based on the detection results of the jacket pressure sensor 18A, the supply of steam by the jacket steam supply device 10 is controlled so that the jacket space 22 maintains a constant pressure. Drain generated in the jacket space 22 is discharged from the jacket space 22 by the jacket drain discharge device 11.

[0036] Air discharge treatment (step SA2) refers to the process of discharging air from the processing space 21 of the chamber 8 using steam supplied from the boiler 2. In the air discharge treatment, the chamber steam feed device 15 supplies steam to the processing space 21 of the chamber 8. Steam from the header 3 is supplied to the processing space 21 via the chamber steam feed line 39.

[0037] In the air discharge process, with the pressure reduction by the pressure reducing device 13 stopped, steam is supplied to the processing space 21 by the chamber steam supply device 15, and gas is discharged from the processing space 21 by the chamber exhaust device 17. In this embodiment, with the chamber exhaust valve 45 open, the chamber steam supply valve 40 opens, supplying steam to the processing space 21 and pushing out air from the processing space 21. After the supply of steam by the chamber steam supply device 15 and the discharge of gas by the chamber exhaust device 17 are completed, the processing space 21 is depressurized by the pressure reducing device 13. In this embodiment, with the chamber steam supply valve 40 and the chamber exhaust valve 45 closed, the vacuum valve 32 opens, depressurizing the processing space 21. After the depressurization by the pressure reducing device 13 is completed, steam is supplied to the processing space 21 by the chamber steam supply device 15. After steam is supplied to the processing space 21 by the chamber steam supply device 15 until the processing space 21 reaches atmospheric pressure, the processing space 21 is depressurized by the pressure reducing device 13. Air is removed from the processing space 21 by repeatedly reducing the pressure in the processing space 21 and supplying steam to the processing space 21.

[0038] Sterilization (step SA3) is performed after the air discharge treatment. Sterilization refers to the process of sterilizing the objects to be sterilized located in the processing space 21 of the chamber 8 using steam supplied from the boiler 2. In the sterilization process, the chamber steam supply device 15 supplies steam to the processing space 21 of the chamber 8. Steam from the header 3 is supplied to the processing space 21 via the chamber steam supply line 39.

[0039] During the sterilization process, with the vacuum device 13 depressurized, steam is supplied to the processing space 21 by the chamber steam supply device 15. Based on the detection result of the chamber temperature sensor 20B, the supply of steam by the chamber steam supply device 15 is controlled so that the processing space 21 is maintained at a specified sterilization temperature for a specified sterilization time.

[0040] The steam exhaust treatment (step SA4) is performed after the sterilization treatment. Steam exhaust treatment refers to the process of exhausting steam from the treatment space 21 of the chamber 8.

[0041] In the steam discharge treatment, with the supply of steam from the chamber steam supply device 15 stopped, gas is discharged from the treatment space 21 by the chamber exhaust device 17. In this embodiment, steam is discharged from the treatment space 21 when the chamber exhaust valve 45 is opened while the chamber steam supply valve 40 is closed.

[0042] The drying and cooling process (step SA5) is performed after the steam discharge process. The drying process refers to the process of drying the objects to be sterilized located in the processing space 21 of the chamber 8. The cooling process refers to the process of cooling the objects to be sterilized located in the processing space 21 of the chamber 8. The user of the steam system 1 selects either the drying process or the cooling process based on the objects to be sterilized.

[0043] During the drying process, the processing space 21 is depressurized by the vacuum device 13. The sterilization target is dried by the depressurization of the processing space 21. During the cooling process, the sterilization target is left in the processing space 21 for a predetermined time.

[0044] The process that uses the most steam supplied from boiler 2 is determined based on whether the steam sterilizer 5 is started in a cold state or a warm state. Cold state means that the temperature of the steam sterilizer 5 before startup is the same as or below a predetermined temperature. Cold start means starting the steam sterilizer 5 when its temperature before startup is the same as or below a predetermined temperature. Warm state means that the temperature of the steam sterilizer 5 before startup is above a predetermined temperature. Warm start means starting the steam sterilizer 5 when its temperature before startup is above a predetermined temperature. The predetermined temperature may be the ambient temperature around the steam sterilizer 5 before startup, or a predetermined specified temperature.

[0045] Whether the steam sterilizer 5 is cold or warm is determined based on at least one of the pressure and temperature of the jacket space 22 of the jacket 9 before the steam sterilizer 5 is started. That is, whether the steam sterilizer 5 is cold or warm is determined based on at least one of the detection data of the jacket pressure sensor 18A and the jacket temperature sensor 20A before the steam sterilizer 5 is started. If the steam sterilizer 5 does not have a jacket 9, whether the steam sterilizer 5 is cold or warm is determined based on the temperature of the processing space 21 of the chamber 8 before the steam sterilizer 5 is started. That is, if the steam sterilizer 5 does not have a jacket 9, whether the steam sterilizer 5 is cold or warm is determined based on the detection data of the chamber temperature sensor 20B before the steam sterilizer 5 is started.

[0046] In the cold state, among preheating, air exhaust, sterilization, steam exhaust, and drying / cooling, the process that uses the most steam supplied from boiler 2 is preheating, followed by air exhaust, and then sterilization.

[0047] In the warm state, among preheating, air exhaust, sterilization, steam exhaust, and drying / cooling, the process that uses the most steam supplied from boiler 2 is air exhaust, the process that uses the second most steam is preheating, and the process that uses the third most steam is sterilization.

[0048] If preheating is not performed, in both cold and hot conditions, the process that uses the most steam supplied from boiler 2 is the air exhaust process, followed by the sterilization process. In the steam exhaust process and the drying / cooling process, the steam supplied from boiler 2 is not substantially used.

[0049] When preheating is performed, if the start switch is operated, preheating is performed by taking in steam supplied from boiler 2 into jacket 9 and preheating chamber 8. After preheating is performed, air discharge is performed. If the start switch is operated while steam sterilizer 5 is in a warm state, air discharge is performed by using steam supplied from boiler 2 to discharge air from chamber 8.

[0050] [controller] Figure 4 is a block diagram showing a controller 6 according to an embodiment. The controller 6 controls at least one steam sterilizer 5. As shown in Figure 1, in this embodiment, the steam system 1 has four steam sterilizers 5. A controller 6 is placed in each of the four steam sterilizers 5. That is, one controller 6 is provided for each steam sterilizer 5. The four controllers 6 are interconnected. The four controllers 6 can communicate with each other. In this embodiment, the steam sterilizer 5 that is scheduled to be operated is appropriately referred to as the first steam sterilizer 51, and the steam sterilizer 5 that is already in operation is appropriately referred to as the second steam sterilizer 52. Operation of the steam sterilizers 5 (51, 52) means performing at least one of the following processes, as described with reference to Figure 3: preheating, air discharge, sterilization, steam discharge, and drying / cooling.

[0051] The controller 6 includes a start signal receiving unit 61, a steam generation amount calculation unit 62, an operating status acquisition unit 63, a standby command unit 64, an operation control unit 65, and a priority setting unit 66. Each of the four controllers 6 has equivalent functions.

[0052] The activation signal receiving unit 61 receives an activation signal to activate the first steam sterilizer 51. As described above, an activation switch is provided on the steam sterilizer 5, which is operated to activate the steam sterilizer 5. When the activation switch provided on the first steam sterilizer 51 is operated, an activation signal is generated to activate the first steam sterilizer 51. The activation signal receiving unit 61 receives the activation signal generated by the operation of the activation switch.

[0053] The generated steam amount calculation unit 62 calculates the generated steam amount, which indicates the amount of steam generated from the boiler 2. The generated steam amount corresponds to the amount of steam collected in the header 3. When there is one boiler 2 in operation, the generated steam amount is the amount of steam generated from that one boiler 2. When there are multiple boilers 2 in operation, the generated steam amount is the sum of the amount of steam generated by each of the multiple boilers 2. In this embodiment, the generated steam amount calculation unit 62 calculates the generated steam amount based on at least one of the number of operational boilers 2, the combustion state of the operational boilers 2, and the header pressure, which indicates the pressure of the header 3 connected to the boiler 2. The header pressure is detected by the pressure sensor 4. The generated steam amount calculation unit 62 can calculate the generated steam amount, for example, based on the detection data of the pressure sensor 4.

[0054] The operating status acquisition unit 63 acquires the operating status of the second steam sterilizer 52. The operating status of the second steam sterilizer 52 includes at least one of the following states: preheating is being performed, air is being discharged, sterilization is being performed, steam is being discharged, and drying and cooling is being performed.

[0055] The standby command unit 64, upon receiving a start signal and determining that there is insufficient steam supplied from the boiler 2 to the first steam sterilizer 51, outputs a standby command to cause the first steam sterilizer 51 to wait before performing a predetermined process. In other words, the standby command unit 64, upon determining that there is insufficient steam supplied from the boiler 2 to the first steam sterilizer 51 whose start switch has been operated, outputs a standby command to cause the first steam sterilizer 51 to wait before performing a predetermined process.

[0056] The standby command unit 64 determines whether there is insufficient steam supplied from the boiler 2 to the first steam sterilizer 51, whose start switch has been operated, based on the amount of steam generated by the boiler 2 calculated by the steam generation amount calculation unit 62 and the operating status of the second steam sterilizer 52 acquired by the operating status acquisition unit 63.

[0057] Figure 5 is a diagram illustrating the determination method by the standby command unit 64 according to the embodiment. The amount of steam generated by boiler 2 is calculated by the generated steam amount calculation unit 62. The generated steam amount calculation unit 62 can calculate the amount of steam generated by boiler 2 based on at least one of the number of operating boilers 2, the combustion state of the operating boilers 2, and the header pressure. The standby command unit 64 can estimate the current usage amount, which indicates the amount of steam used by the second steam sterilizer 52, based on the number of operating second steam sterilizers 52 and the operating state of the second steam sterilizers 52. The standby command unit 64 can also estimate the planned usage amount, which indicates the amount of steam that the first steam sterilizer 51 is scheduled to use when the start switch is operated.

[0058] If there is one second steam sterilizer 52 in operation, the current usage is the amount of steam used by that single second steam sterilizer 52. If there are multiple second steam sterilizers 52 in operation, the current usage is the sum of the amounts of steam used by each of the multiple second steam sterilizers 52.

[0059] If only one steam sterilizer 51 has its activation switch operated, the planned usage is the amount of steam that the single steam sterilizer 51 is scheduled to use. If multiple steam sterilizers 51 have their activation switches operated, the planned usage is the sum of the amounts of steam that each of the multiple steam sterilizers 51 is scheduled to use.

[0060] The standby command unit 64 determines that if the sum of the current usage and the planned usage exceeds the amount of steam generated, there will be insufficient steam supplied from the boiler 2 to the first steam sterilizer 51 when the start switch is operated. The standby command unit 64 determines that if the sum of the current usage and the planned usage is less than the amount of steam generated, there will be sufficient steam supplied from the boiler 2 to the first steam sterilizer 51 when the start switch is operated.

[0061] As described above, in the cold state, among preheating, air exhaust, sterilization, steam exhaust, and drying / cooling, the process that uses the most steam from the steam sterilizer 5 is preheating, followed by air exhaust, and then sterilization. In the warm state, among preheating, air exhaust, sterilization, steam exhaust, and drying / cooling, the process that uses the most steam from the steam sterilizer 5 is air exhaust, followed by preheating, and then sterilization. If preheating is not performed, in both the cold and warm states, the process that uses the most steam from the steam sterilizer 5 is air exhaust, followed by sterilization. In the steam exhaust and drying / cooling processes, the amount of steam used by the steam sterilizer 5 is virtually zero. The amount of steam used by a single steam sterilizer 5 in each of the following processes—preheating, air exhaust, sterilization, steam exhaust, and drying / cooling—is generally fixed. In other words, the amount of steam used by a single steam sterilizer 5 in each of the following processes—preheating, air exhaust, sterilization, steam exhaust, and drying / cooling—is known data.

[0062] Therefore, the standby command unit 64 can estimate the current usage amount, which indicates the amount of steam being used by the second steam sterilizer 52, based on the number of second steam sterilizers 52 in operation and the operating status of the second steam sterilizers 52 in operation.

[0063] Furthermore, if preheating is performed in a cold state, the first steam sterilizer 51, when the start switch is operated, is scheduled to perform preheating immediately after startup. If preheating is performed in a warm state, the first steam sterilizer 51, when the start switch is operated, is scheduled to perform air discharge immediately after startup. If preheating is not performed, the first steam sterilizer 51, when the start switch is operated, is scheduled to perform air discharge immediately after startup. Therefore, the standby command unit 64 can estimate the planned usage amount, which indicates the amount of steam that the first steam sterilizer 51, when the start switch is operated, is scheduled to use.

[0064] The standby command unit 64 can determine whether the start signal was received by the start signal receiving unit 61 in a cold or warm state, based on at least one of the pressure and temperature of the jacket space 22 of the jacket 9. In other words, the standby command unit 64 can determine whether the first steam sterilizer 51, when the start switch is operated, will start in a cold state or a warm state, based on at least one of the detection data of the jacket pressure sensor 18A and the detection data of the jacket temperature sensor 20A. In other words, the standby command unit 64 can determine whether the first steam sterilizer 51, when the start switch is operated, is scheduled to perform preheating treatment or air discharge treatment immediately after startup, based on at least one of the detection data of the jacket pressure sensor 18A and the detection data of the jacket temperature sensor 20A.

[0065] Furthermore, if the steam sterilizer 5 does not have a jacket 9, the standby command unit 64 determines, based on the temperature of the processing space 21 of the chamber 8, whether the start signal was received by the start signal receiving unit 61 in a cold or warm state. In other words, the standby command unit 64 can determine, based on the detection data of the chamber temperature sensor 20B, whether the first steam sterilizer 51, when the start switch is operated, will start in a cold state or a warm state. In other words, the standby command unit 64 can determine, based on the detection data of the chamber temperature sensor 20B, whether the first steam sterilizer 51, when the start switch is operated, is scheduled to perform preheating treatment or air discharge treatment immediately after startup.

[0066] If the standby command unit 64 determines that there is insufficient steam supplied from the boiler 2 to the first steam sterilizer 51 after the start switch has been operated, it outputs a standby command to put the first steam sterilizer 51 on standby before performing a predetermined process. In this embodiment, the predetermined process is a process performed immediately after the first steam sterilizer 51 is started. If it is determined that the first steam sterilizer 51 will be started in a cold state after the start switch has been operated, the predetermined process is a preheating process in which steam supplied from the boiler 2 in a cold state is taken into the jacket 9 to preheat the chamber 8 of the first steam sterilizer 51. If it is determined that the first steam sterilizer 51 will be started in a warm state after the start switch has been operated, the predetermined process is an air discharge process in which air is discharged from the chamber 8 of the first steam sterilizer 51 using steam supplied from the boiler 2 in a warm state.

[0067] While the first steam sterilizer 51 is on standby for the execution of a predetermined process, if the standby command unit 64 determines that the amount of steam supplied from the boiler 2 to the first steam sterilizer 51 is sufficient, based on the amount of steam generated by the boiler 2 and the operating status of the second steam sterilizer 52, the standby command unit 64 outputs a release command to cancel the standby for the execution of the predetermined process. For example, if a second steam sterilizer 52 transitions from sterilization to steam discharge, or if the operation of a second steam sterilizer 52 ends, the current usage decreases, so the standby command unit 64 can output a release command. Upon outputting the release command, the first steam sterilizer 51, whose start switch has been operated, begins operation. When the first steam sterilizer 51, whose start switch has been operated, is in a cold state, upon outputting the release command, the first steam sterilizer 51 sequentially performs preheating, air discharge, sterilization, steam discharge, and drying / cooling processes. When the first steam sterilizer 51 is in a warm state after the start switch has been operated, a release command is output, causing the first steam sterilizer 51 to sequentially perform air discharge, sterilization, steam discharge, and drying / cooling processes.

[0068] The operation control unit 65 controls the operation of the steam sterilizer 5. The operation control unit 65 controls the operation of the first steam sterilizer 51 and the second steam sterilizer 52, respectively.

[0069] The priority setting unit 66 sets priorities for at least some of the multiple steam sterilizers 5. The priority setting unit 66 sets priorities for at least some of the first steam sterilizer 51 and the second steam sterilizer 52. An input device (not shown) is connected to the controller 6. The user of the steam system 1 can set priorities for the multiple steam sterilizers 5 by operating the input device. The priority setting unit 66 sets priorities for the multiple steam sterilizers 5 based on the input signals generated by the operation of the input device. The operation control unit 65 controls the operation of the first steam sterilizer 51 and the second steam sterilizer 52 based on the priorities set by the priority setting unit 66.

[0070] The priority order includes the priority for starting the operation of steam sterilizer 5. Steam sterilizers with higher priority 5 will be started first, and steam sterilizers with lower priority 5 will be stopped first.

[0071] For example, as shown in Figure 1, if the steam system 1 has four steam sterilizers 5, the priority setting unit 66 can set a priority for starting operation for each of the four steam sterilizers 5. In a situation where a steam sterilizer 5 with a lower priority is in operation and a steam sterilizer 5 with a higher priority is not in operation, that is, when the priority of the second steam sterilizer 52 is low and the priority of the first steam sterilizer 51 is high, if the start switch to start the first steam sterilizer 51 is operated, the operation control unit 65 will stop the operation of the second steam sterilizer 52, which has a lower priority, and start the operation of the first steam sterilizer 51, which has a higher priority, based on the start signal received by the start signal receiving unit 61 and the priority for starting operation set by the priority setting unit 66.

[0072] Furthermore, the priority order includes the priority for releasing the standby status of the first steam sterilizer 51. The higher the priority of the first steam sterilizer 51, the more quickly the standby status will be released, and the lower the priority of the first steam sterilizer 51, the more quickly the standby status will continue.

[0073] For example, if there are two first steam sterilizers 51, and each of the two first steam sterilizers 51 is waiting to perform a predetermined process, if the standby status of both first steam sterilizers 51 is released simultaneously, the amount of steam supplied from the boiler 2 to the first steam sterilizers 51 will be insufficient. However, if the standby status of only one first steam sterilizer 51 is released, the amount of steam supplied from the boiler 2 to the first steam sterilizer 51 may be sufficient. In such a case, a priority order for releasing the standby status is set for each of the two first steam sterilizers 51. If the standby command unit 64 determines that the amount of steam supplied from the boiler 2 to one first steam sterilizer 51 is sufficient, it releases the standby status of the first steam sterilizer 51 with the higher priority and continues the standby status of the first steam sterilizer 51 with the lower priority.

[0074] [Steam sterilization method] Figure 6 is a flowchart illustrating a steam sterilization method according to an embodiment. When the start switch provided on the first steam sterilizer 51 is operated, a start signal is output from the start switch. The start signal receiving unit 61 receives the start signal to start the first steam sterilizer 51 (step SB1).

[0075] The generated steam amount calculation unit 62 calculates the generated steam amount, which indicates the amount of steam generated from the boiler 2. The generated steam amount calculation unit 62 calculates the generated steam amount based on at least one of the number of operational boilers 2, the combustion state of the operational boilers 2, and the header pressure, which indicates the pressure of the header 3 connected to the boiler 2 (step SB2).

[0076] The operating status acquisition unit 63 acquires the operating status of the second steam sterilizer 52. If there are multiple second steam sterilizers 52, the operating status acquisition unit 63 acquires the operating status of each of the multiple second steam sterilizers 52 (step SB3).

[0077] Note that the processing of step SB3 may be performed before the processing of step SB2, or the processing of step SB2 and step SB3 may be performed simultaneously.

[0078] The standby command unit 64 determines whether there is insufficient steam supplied from the boiler 2 to the first steam sterilizer 51, from which a start signal was obtained in step SB1, based on the amount of steam generated by the boiler 2 calculated in step SB2 and the operating status of the second steam sterilizer 52 obtained in step SB3 (step SB4).

[0079] As explained with reference to Figure 5, the standby command unit 64 determines that if the sum of the current usage of the second steam sterilizer 52 and the planned usage of the first steam sterilizer 51 exceeds the amount of steam generated by the boiler 2, there will be insufficient steam supplied from the boiler 2 to the first steam sterilizer 51 when the start switch is operated. The standby command unit 64 determines that if the sum of the current usage of the second steam sterilizer 52 and the planned usage of the first steam sterilizer 51 is less than the amount of steam generated by the boiler 2, there will be sufficient steam supplied from the boiler 2 to the first steam sterilizer 51 when the start switch is operated.

[0080] In step SB4, if it is determined that there is insufficient steam supplied to the first steam sterilizer 51 (step SB4: Yes), the standby command unit 64 determines whether the first steam sterilizer 51, whose activation switch has been operated, is in a cold state or not. The standby command unit 64 determines whether the first steam sterilizer 51, whose activation switch has been operated, is in a cold state or not based on at least one of the pressure and temperature of the jacket 9 of the first steam sterilizer 51 (step SB5).

[0081] In step SB5, if it is determined that the first steam sterilizer 51 is in a cold state (step SB5: Yes), the standby command unit 64 outputs a standby command to the first steam sterilizer 51 to put it on standby before performing the preheating process (step SB6).

[0082] In step SB5, if it is determined that the first steam sterilizer 51 is in a warm state (step SB5: No), the standby command unit 64 outputs a standby command to the first steam sterilizer 51 to put it on standby before performing the air discharge treatment (step SB7).

[0083] In step SB4, if it is determined that the steam supplied to the first steam sterilizer 51 is sufficient (step SB4: No), the standby command unit 64 does not output a standby command. The first steam sterilizer 51, when the start switch is operated, starts operation. If the first steam sterilizer 51 is started in a cold state, the first steam sterilizer 51 sequentially performs preheating, air discharge, sterilization, steam discharge, and drying / cooling. If the first steam sterilizer 51 is started in a warm state, the first steam sterilizer 51 sequentially performs air discharge, sterilization, steam discharge, and drying / cooling (step SB8).

[0084] After the processing in step SB6, the controller 6 returns to the processing in step SB2. In step SB4, if it is determined that the amount of steam supplied from boiler 2 to the first steam sterilizer 51 is sufficient based on the amount of steam generated by boiler 2 and the operating status of the second steam sterilizer 52 (step SB4: No), the standby command unit 64 outputs a release command to the first steam sterilizer 51 to cancel the standby for the preheating process of the first steam sterilizer 51. The first steam sterilizer 51 sequentially performs the preheating process, air discharge process, sterilization process, steam discharge process, and drying / cooling process (step SB8).

[0085] After the processing in step SB7, the controller 6 returns to the processing in step SB2. In step SB4, if the controller 6 determines that the amount of steam supplied from the boiler 2 to the first steam sterilizer 51 is sufficient based on the amount of steam generated by the boiler 2 and the operating status of the second steam sterilizer 52 (step SB4: No), the standby command unit 64 outputs a release command to the first steam sterilizer 51 to cancel the standby for the air discharge process of the first steam sterilizer 51. The first steam sterilizer 51 then sequentially performs the air discharge process, sterilization process, steam discharge process, and drying / cooling process (step SB8).

[0086] Furthermore, if the priority setting unit 66 sets a priority for starting operation for each of the multiple steam sterilizers 5, and the priority of the second steam sterilizer 52 is low and the priority of the first steam sterilizer 51 is high, and in step SB4 it is determined that there is insufficient steam supplied to the first steam sterilizer 51, the operation control unit 65 may stop the operation of the second steam sterilizer 52, which has a lower priority, based on the start signal received by the start signal receiving unit 61 in step SB1 and the priority set by the priority setting unit 66. By stopping the operation of the second steam sterilizer 52, which has a lower priority, the steam supplied from the boiler 2 to the first steam sterilizer 51 is sufficient, and the first steam sterilizer 51, which has a higher priority, can start operation.

[0087] [effect] As described above, the controller 6 of the steam sterilizer 5 includes a start signal receiving unit 61 that receives a start signal to start the first steam sterilizer 51 which uses steam supplied from the boiler 2, and a standby command unit 64 that, when a start signal is received and it is determined that there is insufficient steam supplied from the boiler 2 to the first steam sterilizer 51, outputs a standby command to put the first steam sterilizer 51 on standby before performing a predetermined process.

[0088] According to this embodiment, when the first steam sterilizer 51 is started while the second steam sterilizer 52 is in operation, if there is a possibility that the steam supplied from the boiler 2 to the first steam sterilizer 51 will be insufficient, the start of the first steam sterilizer 51 will be put on hold. This ensures that the steam supplied from the boiler 2 to the second steam sterilizer 52 is sufficient without increasing the number of boilers 2 in operation. As a result, the energy consumption of the boiler 2 is suppressed, and the second steam sterilizer 52 is operated properly. In addition, interruptions in the operation of the second steam sterilizer 52 due to insufficient steam supplied from the boiler 2 are suppressed. Since the second steam sterilizer 52 is operated properly, the items to be sterilized are properly sterilized in the second steam sterilizer 52.

[0089] The controller 6 of the steam sterilizer 5 includes a steam generation amount calculation unit 62 that calculates the amount of steam generated from the boiler 2, and an operating status acquisition unit 63 that acquires the operating status of the second steam sterilizer 52 which uses steam supplied from the boiler 2. The standby command unit 64 can determine whether or not there is insufficient steam supplied from the boiler 2 to the first steam sterilizer 51 based on the amount of steam generated by the boiler 2 and the operating status of the second steam sterilizer 52.

[0090] Based on the amount of steam generated by boiler 2 and the operating status of the second steam sterilizer 52, if the standby command unit 64 determines that the steam supplied from boiler 2 to the first steam sterilizer 51 is sufficient, it releases the standby for the predetermined processing of the first steam sterilizer 51. As a result, the first steam sterilizer 51 operates properly with sufficient steam supplied from boiler 2.

[0091] The first steam sterilizer 51 has a chamber 8 in which the items to be sterilized are contained, and a jacket 9 positioned around the chamber 8. The standby command unit 64 can determine whether the activation signal was received in a cold or warm state, based on at least one of the pressure and temperature of the jacket 9.

[0092] In the cold state, the predetermined process subject to the standby command is a preheating process in which steam supplied from the boiler 2 is taken into the jacket 9 during cold startup to preheat the chamber 8 of the first steam sterilizer 51. The startup of the first steam sterilizer 51 is put on standby because the preheating process, which is scheduled to be performed immediately after the startup of the first steam sterilizer 51 in the cold state, is put on standby.

[0093] In the warm state, the predetermined process subject to the standby command is the air discharge process, which uses steam supplied from the boiler 2 during warm state startup to discharge air from the chamber 8 of the first steam sterilizer 51. The startup of the first steam sterilizer 51 is put on standby because the air discharge process, which is scheduled to be performed immediately after the startup of the first steam sterilizer 51 in the warm state, is put on standby.

[0094] If preheating is not performed, the predetermined process subject to the standby command is the air discharge process, which uses steam supplied from the boiler 2 to discharge air from the chamber 8 of the first steam sterilizer 51. The air discharge process, which is scheduled to be performed immediately after the startup of the first steam sterilizer 51, is put on standby, causing the startup of the first steam sterilizer 51 to be put on standby.

[0095] The controller 6 of the steam sterilizer 5 includes a priority setting unit 66 that sets priority levels for at least some of the first steam sterilizer 51 and the second steam sterilizer 52, and an operation control unit that controls the operation of the first steam sterilizer 51 and the second steam sterilizer 52 based on the priority levels set by the priority setting unit 66. The priority setting unit 66 can, for example, set priority levels related to the start of operation. For example, if the priority level of the first steam sterilizer 51 is higher than that of the second steam sterilizer 52, the operation control unit 65 can stop the operation of at least one of the second steam sterilizers 52 and start the operation of the first steam sterilizer 51 when the start switch of the first steam sterilizer 51 is operated. This eliminates the need for the higher-priority steam sterilizer 5 to wait for a predetermined process, or shortens the waiting time for the predetermined process of the higher-priority steam sterilizer 5.

[0096] [Other embodiments] Figure 7 is a schematic diagram showing a steam system 100 according to another embodiment. In the above-described embodiment, a controller 6 is provided for each of the multiple steam sterilizers 5, and one controller 6 controls the multiple steam sterilizers 5 (51, 52) on behalf of the others, or multiple controllers 6 cooperate to control the multiple steam sterilizers 5 (51, 52). As shown in Figure 7, one higher-level controller 600 may be connected to the controllers 7 provided for each of the multiple steam sterilizers 5 (51, 52). Each of the multiple controllers 7 individually controls the operation of the steam sterilizer 5 to which the controller 7 is provided. As described above, the operation of the steam sterilizer 5 means performing at least one of the processes described with reference to Figure 3: preheating, air discharge, sterilization, steam discharge, and drying / cooling. The higher-level controller 600 has a start signal receiving unit 61, a generated steam amount calculation unit 62, an operating state acquisition unit 63, a standby command unit 64, an operation control unit 65, and a priority setting unit 66, as described in the above-described embodiment. If the higher-level controller 600 determines that there is insufficient steam supplied to the first steam sterilizer 51, which is one of the multiple steam sterilizers 5 that is scheduled to be operated, it can output a standby command to cause the first steam sterilizer 51 to wait before performing its predetermined processing.

[0097] In the embodiment described with reference to Figures 1 and 7 above, the standby command unit 64 may determine whether there is insufficient steam supplied to the first steam sterilizer 51 whose start switch has been operated from the boiler 2, based on, for example, the number of boilers scheduled to operate and a set value for the number of steam sterilizers 5 to be operated, which is set based on the capacity of the boilers 2 scheduled to operate. For example, if the number of steam sterilizers 5 to be operated exceeds the set value when a certain first steam sterilizer 51 is started, the standby command unit 64 may determine that there is insufficient steam. In this case, the standby command unit 64 outputs a standby command to put the start of the first steam sterilizer 51 whose start switch has been operated on hold. More specifically, when the steam system 1 has 5 boilers 2 and 7 steam sterilizers 5, and 2 boilers 2 are to be operated, the number of steam sterilizers 5 to be operated is set to 3 based on the capacity of the 2 boilers. When two boilers 2 are operating and three steam sterilizers 5 (second steam sterilizer 52) are running, if the start switch for a fourth steam sterilizer 5 (first steam sterilizer 51) is operated, the standby command unit 64 determines that there is a steam shortage and puts the fourth steam sterilizer 5 on standby for startup. After one of the three steam sterilizers 5 (second steam sterilizer 52) that are currently running has finished operating, the standby command unit 64 releases the standby for startup of the fourth steam sterilizer 5. If the number of operating steam sterilizers 5 falls below a set value even after a first steam sterilizer 51 is started, the standby command unit 64 may determine whether there is a steam shortage when supplying steam to the first steam sterilizer 51 whose start switch has been operated from the boiler 2, based on the amount of steam generated calculated by the generated steam amount calculation unit 62 and the operating status of the second steam sterilizer 52 acquired by the operating status acquisition unit 63.

[0098] In the embodiment described above, the controller 6 controls the steam sterilizer 5. The controller 6 may also control a steam sterilizer (including a retort). That is, the steam system 1 may include multiple steam sterilizers instead of the steam sterilizer 5. The steam sterilizers sterilize the items to be sterilized using steam supplied from the boiler 2. [Explanation of Symbols]

[0099] 1...Steam system, 2...Boiler, 3...Header, 4...Pressure sensor, 5...Steam sterilizer (steam sterilizer / disinfector), 6...Controller, 7...Controller, 8...Chamber, 9...Jacket, 10...Jacket steam feed device, 11...Jacket drain discharge device, 12...Jacket exhaust device, 13...Depressurization device, 14...Restoration device, 15...Chamber steam feed device, 16...Chamber drain discharge device, 17...Chamber exhaust device, 18A...Jacket pressure sensor, 18B...Chamber pressure sensor, 20A...Jacket temperature sensor, 20B...Chamber temperature sensor, 21...Processing space, 22...Jacket space, 23...Jacket steam feed line, 24...Jacket steam feed valve, 25...Jacket drain discharge line, 26...Steam trap, 27...Check valve, 28...Jacket exhaust line, 2 9...Jacket exhaust valve, 30...Check valve, 31...Vacuum line, 32...Vacuum valve, 33...Vacuum pump, 34...Check valve, 35...Air supply line, 36...Sterile filter, 37...Air supply valve, 38...Check valve, 39...Chamber steam supply line, 40...Chamber steam supply valve, 41...Chamber drain discharge line, 41A...First section, 41B...Second section, 42...Steam trap, 43...Check valve, 44...Chamber exhaust line, 45...Chamber exhaust valve, 46...Check valve, 47...Check valve, 51...First steam sterilizer (first steam sterilizer / disinfector), 52...Second steam sterilizer (second steam sterilizer / disinfector), 61...Start signal receiving unit, 62...Steam generation amount calculation unit, 63...Operating status acquisition unit, 64...Standby command unit, 65...Operation control unit, 66...Priority setting unit, 100...Steam system, 600...Higher-level controller.

Claims

1. A steam generation amount calculation unit that calculates the amount of steam generated from a boiler, A start signal receiving unit receives a start signal to start the first steam sterilizer / sterilizer, which is scheduled to be operated using steam supplied from the boiler, An operating status acquisition unit that acquires the operating status of a second steam sterilizer / sterilizer that is already in operation by using steam supplied from the boiler, The system includes a standby command unit that, upon receiving the startup signal and determining that there is insufficient steam supplied from the boiler to the first steam sterilizer / disinfector, outputs a standby command to postpone the execution of the predetermined processing of the first steam sterilizer / disinfector that is scheduled to be performed immediately after startup, The standby command unit, Immediately after startup, the planned usage amount, which indicates the amount of steam that the first steam sterilizer / sterilizer is scheduled to use in the prescribed process to be performed, is estimated. Based on the aforementioned operating conditions, the current usage amount, which indicates the amount of steam being used by the second steam sterilizer / sterilizer, is estimated. Based on the amount of steam generated, the planned usage, and the current usage, it is determined whether or not there is a shortage of steam supplied from the boiler to the first steam sterilizer / sterilizer. Controller for steam sterilizers and disinfecters.

2. Based on the amount of steam generated, the planned usage, and the current usage, if the standby command unit determines that the amount of steam supplied from the boiler to the first steam sterilizer / sterilizer is sufficient, the standby command unit cancels the standby state. A controller for a steam sterilizer / sterilizer as described in claim 1.

3. The first steam sterilizer / sterilizer has a chamber in which the object to be sterilized is contained, The predetermined process is an air discharge process that uses steam supplied from the boiler to discharge air from the chamber of the first steam sterilizer / sterilizer. A controller for a steam sterilizer / sterilizer as described in claim 1.

4. The first steam sterilizer / sterilizer comprises a chamber in which the object to be sterilized is contained, and a jacket positioned around the chamber. The standby command unit determines whether the jacket is cold or warm based on at least one of the pressure and temperature of the jacket. The aforementioned predetermined process is a preheating process in which steam supplied from the boiler in a cold state is taken into the jacket to preheat the chamber of the first steam sterilizer / sterilizer. A controller for a steam sterilizer / sterilizer as described in claim 1.

5. The aforementioned predetermined process is an air discharge process that uses steam supplied from the boiler at a warm temperature to discharge air from the chamber of the first steam sterilizer / sterilizer. A controller for a steam sterilizer / sterilizer according to claim 4.

6. A priority setting unit that sets a priority order for at least a portion of the first steam sterilizer and the second steam sterilizer, The system includes an operation control unit that controls the operation of the first steam sterilizer and the second steam sterilizer based on the aforementioned priority order. A controller for a steam sterilizer / sterilizer according to claim 2.

7. Multiple boilers are provided, The steam generation amount calculation unit calculates the steam generation amount based on at least one of the number of operational boilers, the combustion state of the operating boilers, and the header pressure, which indicates the pressure of the header connected to the boiler. A controller for a steam sterilizer / sterilizer as described in claim 1.

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