JP2011245220A - Steam sterilizer and operation control method therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a steam sterilizer for aiming to reduce the temperature in a machine room and its adjacent room and reducing an equipment cost and energy cost devised by countermeasure against high temperature.SOLUTION: A steam sterilizer is used for sterilization operation including a warming-up operation for warming a sterilization room by supplying steam to a steam jacket 2 during starting and to the sterilization room 1 if necessary, a preheating process for warming a sterilized subject stored in the sterilization room by heat from the steam jacket, an air emission process for emitting the air in the sterilization room, a steam supplying process for supplying steam to the saturated vapor pressure at the preset temperature in the sterilization room, a sterilization process for holding the preset temperature in the sterilization room during the predetermined period, a steam emission process for emitting the steam in the sterilization room after sterilization, and a dry process for drying the sterilized subject in the sterilization room, and it has a control means for closing a steam supply valve 3 of an outer can which supplies the steam to the steam jacket and blocking the steam supply to the steam jacket after the end of the warming-up operation before the start of a first sterilization operation and before the start of the next sterilization operation after the end of sterilization operation.

Description

  The present invention relates to a steam sterilization apparatus and an operation control method thereof. The steam sterilization apparatus of the present invention is mainly used to sterilize medical instruments, clothes, and the like.

  The steam sterilization apparatus is an apparatus for supplying sterilization to a sterilization chamber and a steam jacket provided outside the sterilization chamber, and performing sterilization processing by the heat held by the steam after the object to be sterilized is accommodated in the sterilization chamber. As such a steam sterilization apparatus, normally, a warm-up process in which steam is supplied into a steam jacket at the time of start-up and warmed so that sterilization operation can be performed immediately, and an object to be sterilized is preheated by heat from the steam jacket. Preheating process, air evacuation process for excluding air in the sterilization room, steaming process for supplying steam to the sterilization room excluding air, sterilization process for maintaining the sterilization room filled with steam for a predetermined time, Sterilization operation is performed in the order of a steam exhausting process for discharging steam and a drying process for drying the sterilized material after exhausting, and the next sterilization operation after the drying process starts from the air exclusion process (preheating process if set) The process is provided (for example, refer patent document 1, 2).

  In the operation of the steam sterilization apparatus having such an operation process, for example, when the steam sterilization apparatus is in a cold state before the morning work, the warm-up operation is started by operating the power switch. Steam is supplied to the steam jacket, and the steam pressure of the steam jacket is maintained at or above the steam pressure during sterilization. In the sterilization operation, each step of the sterilization operation is performed by operating the sterilization operation start switch.

  After the sterilization operation is completed, the sterilized operation is taken out by taking out the sterilized product, preparing the next sterilized product, storing it in the steam sterilizer, and operating the sterilization operation start switch again. . The power switch remains in operation even after the sterilization operation is completed, and performs pressure control of the steam jacket and other control related to the safety device. Normally, the power switch remains operated all day until the end of the day's work, and the pressure of the steam jacket is kept at a high pressure.

Japanese Patent Laid-Open No. 11-56974 Japanese Patent Application Laid-Open No. 11-206859

  As described above, in the conventional steam sterilization apparatus, even if the sterilization operation is terminated by the end of the drying process, the steam jacket is kept at a high pressure until the next sterilization operation, that is, until the start of the air exclusion process. In this state, the heat from the steam jacket and the heat from the pipe are about 6 kW per unit.

  In such a steam sterilizer, steam introduction pipes and valves to be controlled are separated from a room called a machine room for cleaning, packaging, etc. Heat from the jacket and piping increases the temperature inside the machine room, which may cause breakdown of equipment in the machine room, and excessive cooling operation is required in the adjacent room, which increases equipment costs and energy costs. There was a problem of being a factor.

  The object of the present invention is to reduce the heat radiation from the steam jacket and the piping in the operation of the steam sterilizer so as not to use the steam as much as possible after the sterilization operation until the next sterilization operation. Accordingly, an object of the present invention is to provide a steam sterilization apparatus and an operation control method thereof for reducing the temperature in the machine room and the adjacent room and reducing the equipment cost and the energy cost taken as countermeasures for the high temperature.

  In order to achieve the above object, the invention according to claim 1 is housed in the sterilization chamber, a warm-up operation in which the sterilization chamber is warmed by steaming the steam jacket and, if necessary, the sterilization chamber at startup. A preheating step of heating an object to be sterilized by heat from a steam jacket, an air exhausting step of removing air in the sterilization chamber, a steaming step of steaming to a saturated steam pressure at a temperature set in the sterilization chamber, and the sterilization chamber A steam sterilization apparatus for performing a sterilization operation including a sterilization process for maintaining a predetermined temperature for a predetermined time, a steaming process for discharging steam in the sterilization chamber after sterilization, and a drying process for drying an object to be sterilized in the sterilization chamber The outer can that supplies steam to the steam jacket from the end of the warm-up operation to the start of the first sterilization operation and from the completion of the sterilization operation to the start of the next sterilization operation. Steam CLOSING characterized by comprising control means for interrupting the supply steam to the steam jacket.

  According to invention of Claim 1, the temperature reduction in a machine room or an adjacent room can be aimed at, and the installation cost and energy cost taken as a countermeasure against high temperature can be reduced.

  The invention according to claim 2 is a warm-up operation for warming the sterilization chamber by steaming the steam jacket and, if necessary, the sterilization chamber at the time of start-up, and heat to be sterilized from the steam jacket. A preheating step for warming in the air, an air exclusion step for removing air in the sterilization chamber, a steaming step for steaming to a saturated steam pressure that is a temperature set in the sterilization chamber, and a sterilization for holding the sterilization chamber at a set temperature for a predetermined time An operation control method in a steam sterilization apparatus for performing a sterilization operation including a process, a steam exhausting process for discharging steam in the sterilization chamber after sterilization, and a drying process for drying an object to be sterilized in the sterilization chamber, The standby process is from the end of the machine operation to the start of the first sterilization operation and from the completion of the sterilization operation to the start of the next sterilization operation. In the standby process, the steam jacket To preparative close the supply Misir outer can supply 蒸弁 characterized by interrupting the supply steam to the steam jacket.

  According to the second aspect of the present invention, it is possible to reduce the temperature in the machine room and the adjacent room, and to reduce the equipment cost and the energy cost taken as a countermeasure for the high temperature.

  The invention described in claim 3 is provided with the inner can pressure sensor for detecting the pressure in the sterilization chamber and the outer can pressure sensor for detecting the pressure in the steam jacket according to claim 2, The step of supplying steam to the sterilization chamber of the steps includes detecting the steam pressure of the steam jacket and the sterilization chamber by the inner can pressure sensor and the outer can pressure sensor, and the steam pressure of the steam jacket is adjusted in the sterilization chamber. The outer can steaming valve is controlled to be higher than the steam pressure, and the outer can steaming valve is set so that the pressure of the steam jacket in the drying process is equal to the pressure of the steam jacket in the sterilization process. It is characterized by controlling.

  According to the invention of claim 3, the steam used in the steam jacket is reduced as much as possible to prevent condensation on the surface of the sterilization chamber, and the amount of heat from the steam jacket during the drying process is reduced. While preventing, it is possible to reduce the temperature in the machine room and the adjacent room, and to reduce the equipment cost and the energy cost taken as countermeasures for the high temperature.

  According to a fourth aspect of the present invention, in the standby step according to the second or third aspect, when the steam pressure of the steam jacket drops below a predetermined pressure during the standby step, the steam is steamed into the steam jacket. The outer can steam supply valve is controlled to increase the steam pressure of the jacket to at least a predetermined pressure.

  According to the invention of claim 4, the steam used in the steam jacket can be reduced as much as possible, and even a sterilization apparatus that has been in a standby state for a long time can be used for immediate sterilization operation. By reducing the temperature in the room, it is possible to reduce equipment costs and energy costs that are taken as countermeasures against high temperatures.

  According to a fifth aspect of the present invention, in the sterilization operation according to the second or third aspect, the process is not started unless the steam pressure of the steam jacket is increased to a predetermined pressure or more, and the steam jacket is not started. The outer can steam supply valve is controlled to perform steaming, and the process is started after the steam pressure of the steam jacket becomes equal to or higher than a predetermined pressure.

  According to the invention of claim 5, since the steam used in the steam jacket can be reduced as much as possible to prevent condensation on the surface of the sterilization chamber, the condensed water falls on the object to be sterilized. Drying defects can be prevented, the temperature in the machine room and adjacent rooms can be reduced, and equipment costs and energy costs taken as countermeasures for high temperatures can be reduced.

  According to a sixth aspect of the present invention, in the air exclusion process according to any one of the second to fifth aspects, the pressure reduction and the steam supply are alternately performed in the sterilization chamber. The steam valve is closed to shut off the steam supply to the steam jacket.

  According to the invention of claim 6, the steam used in the steam jacket can be reduced as much as possible to prevent condensation on the surface of the sterilization chamber. Drying defects can be prevented, the temperature in the machine room and adjacent rooms can be reduced, and equipment costs and energy costs taken as countermeasures for high temperatures can be reduced.

  According to the present invention, in the operation of the steam sterilization apparatus, after the sterilization operation is completed, the steam is not used as much as possible until the next sterilization operation, and the operation is performed so as to reduce the heat radiation from the steam jacket and the pipe. Since it can be controlled, the temperature in the machine room and the adjacent room can be reduced, and the equipment cost and the energy cost taken as countermeasures for the high temperature can be reduced.

It is explanatory drawing which shows an example of the steam sterilizer which implements this invention. It is explanatory drawing which shows the change of the steam pressure in a sterilization chamber and a steam jacket in each operation process of each 1st Example of the operation control method in the steam sterilization apparatus which concerns on this invention. It is explanatory drawing which shows the change of the steam pressure in a sterilization chamber and a steam jacket in each operation process of each 2nd Example of the operation control method in the steam sterilization apparatus which concerns on this invention. It is explanatory drawing which shows the change of the steam pressure in each sterilization chamber and steam jacket in each operation process of each 3rd Example of the operation control method in the steam sterilization apparatus which concerns on this invention.

Embodiments of the present invention will be described below.
First, an embodiment of a steam sterilization apparatus according to the present invention will be described. The steam sterilization apparatus of this example is also applied to an apparatus used for heat insulation and heating, for example, a cooking apparatus, a dryer, etc., by having a steam jacket on the outer periphery of the treatment tank and introducing steam.
An example of the implementation of the steam sterilization apparatus of this example will be described with reference to FIG. 1. The steam sterilization apparatus of this example is provided with a steam jacket 2 for heating outside the sterilization chamber 1 for storing the article to be sterilized. The steam jacket 2 can be a single room covering almost the entire circumference of the sterilization chamber 1, or a heating tube can be wound around the sterilization chamber 1.

  The steam jacket 2 is connected to an outer can steaming passage 4 having a shut-off valve 28, an outer can steaming valve 3, and a check valve 29. In the outer can steaming path 4, the inner can steaming path 5 for supplying steam to the sterilization chamber 1 by branching the outer can steaming path 4 from between the shutoff valve 28 and the outer can steaming valve 3 is provided in the sterilization chamber 1. Connected to. The inner can steaming passage 5 is provided with an inner can steaming valve 6. The supply of steam to the sterilization chamber 1 and the steam jacket 2 is controlled by controlling the opening and closing of the outer can steam supply valve 3 and the inner can steam supply valve 6.

  An air supply path 7 is connected to a position downstream of the inner can steam supply valve 6 in the inner can steam supply path 5. The air supply path 7 is provided with an air filter 8, an air supply valve 9, and a check valve 10 in order from the upstream side, and aseptic air is supplied to the sterilization chamber 1 through the air supply path 7.

  An inner can exhaust path 11 is connected to the sterilization chamber 1, and an outer can exhaust path 12 is connected to the steam jacket 2. In the inner can exhaust passage 11, an inner can temperature sensor 30, a vacuum exhaust valve 13, a vacuum pump 14, and check valves 15 and 16 are provided. The outer can steaming passage 12 is provided with an outer can steam trap 17 and a check valve 18. A drain discharge passage 19 and a steam discharge passage 20 are branched from the inner can exhaust passage 11, an inner can steam trap 21 and a check valve 22 are provided in the drain discharge passage 19, and a steam exhaust valve 23 is provided in the steam discharge passage 20. And a check valve 24 are provided. The inner can exhaust path 11, the outer can exhaust steam path 12, the drain discharge path 19 and the steam discharge path 20 merge at their downstream positions.

  The sterilization chamber 1 is provided with an inner can pressure sensor 25 for detecting the internal pressure. The steam jacket 2 is provided with an outer can pressure sensor 26 for detecting the internal pressure. Based on detection signals from the inner can pressure sensor 25 and the outer can pressure sensor 26, the controller 27 controls the opening and closing of the outer can feed valve 3 and the inner can feed valve 6.

  The steam sterilization apparatus configured as described above is a warm-up operation for heating the sterilization chamber 1 by steaming the steam jacket 2 and, if necessary, the sterilization chamber 1 at the time of activation, and steaming an object to be sterilized stored in the sterilization chamber 1. A preheating process for warming with the heat of the jacket 2, an air exhausting process for removing air in the sterilization chamber 1, a steaming process for steaming to a saturated steam pressure that is the temperature set in the sterilization chamber 1, and a temperature setting in the sterilization chamber 1 A sterilization operation including a sterilization process for holding for a predetermined time, a steaming process for discharging steam in the sterilization chamber 1 after sterilization, and a drying process for drying the sterilization chamber 1 to be sterilized, The supply of steam to the sterilization chamber 1 and the steam jacket 2 in each process is controlled by the controller 27.

  Then, the controller 27 supplies the outer can that supplies steam to the steam jacket 2 from the end of the warm-up operation to the start of the first sterilization operation and from the completion of the sterilization operation to the start of the next sterilization operation. Control means for closing the steam valve 3 and shutting off the steam supply to the steam jacket 2 is provided.

  According to the steam sterilization apparatus configured as described above, during the sterilization operation, the control means provided in the controller 27 is used until the start of the first sterilization operation after the warm-up operation and after the completion of the sterilization operation. Until the start of the sterilization operation, the outer can steam supply valve 3 for steaming to the steam jacket 2 is closed to shut off steam feeding to the steam jacket 2, thereby reducing the temperature in the machine room and adjacent rooms. Equipment costs and energy costs for high temperature measures can be reduced.

Next, an embodiment of the operation control method in the steam sterilizer according to the present invention will be described.
The operation control method in the steam sterilization apparatus according to the present invention includes a warm-up operation in which steam is supplied to the steam jacket 2 and, if necessary, the sterilization chamber 1 and warmed so that the sterilization operation can be performed immediately. Preheating process for preheating sterilized material by heat from the steam jacket 2, air excluding process for excluding air in the sterilization chamber 1, steaming process for steaming to a saturated steam pressure at a temperature set in the sterilization chamber 1, sterilization A sterilization operation is performed including a sterilization process for maintaining the interior of the chamber 1 at a set temperature for a predetermined time, a steaming process for discharging the steam in the sterilization chamber 1 after sterilization, and a drying process for drying the objects to be sterilized in the sterilization chamber 1. This is an operation control method.

  During the above operation, the waiting process is from the end of the warm-up operation to the start of the first sterilization operation and from the completion of the sterilization operation to the start of the next sterilization operation. The operation is controlled so that the outer can feed valve 3 for steaming is closed and the steam jacket 2 is shut off.

  Further, in the above operation, the step of supplying steam to the sterilization chamber 1 among the steps in the sterilization operation detects the steam pressure in the steam jacket 2 and the sterilization chamber 1 by the inner can pressure sensor 25 and the outer can pressure sensor 26. Then, the outer can feed valve 3 is controlled so that the steam pressure of the steam jacket 2 is higher than the steam pressure of the sterilization chamber 1, and the pressure of the steam jacket 2 in the drying process is the same as that of the steam jacket 2 in the sterilization process. It is good to control the outer can feed valve 3 so that it may become equal to a pressure.

  Further, in the standby process, when the steam pressure of the steam jacket 2 falls below a predetermined pressure during the standby process, steaming is performed in the steam jacket 2 so that the steam pressure of the steam jacket 2 is increased to at least the predetermined pressure. The valve 3 may be controlled.

  The predetermined pressure referred to here is a steam jacket that is earlier than the pressure increase in the sterilization chamber 1 so that the steam supplied into the sterilization chamber 1 does not condense on the wall surface or the upper portion in the sterilization chamber 1 during the sterilization operation. The pressure which can raise the pressure in 2 is said.

  Usually, the temperature in the steam jacket 2 is controlled to a sterilization set temperature + α (135 ° C. + 2.3 ° C.), and the pressure in the steam jacket 2 is a saturated steam pressure corresponding to the sterilization set temperature + α (137.3 ° C.). (233.7 kPaG).

  In a state where the pressure in the steam jacket 2 has decreased to atmospheric pressure after a long time has passed since the power switch was turned off, when the pressure in the steam jacket 2 is increased to a desired saturated steam pressure, the pressure in the steam jacket 2 is slightly longer up to 50 kPaG. Although it takes time, when it exceeds 50 kPaG, it rises to a desired saturated vapor pressure in a relatively short time. Moreover, when it exceeds 100 kPaG, it will rise to the desired saturated vapor pressure in a shorter time. For these reasons, the predetermined pressure is preferably 50 kPaG to 100 kPaG, and more preferably 100 kPaG.

  In the sterilization operation, if the steam pressure of the steam jacket 2 is not higher than the predetermined pressure, the above process is not started, and the outer can feed valve 3 is controlled so as to feed the steam jacket 2. Then, the above process may be started after the steam pressure of the steam jacket 2 becomes equal to or higher than a predetermined pressure.

  Further, in the air exclusion process, the decompression and the steam supply in the sterilization chamber 1 are alternately performed, and the steam supply to the steam jacket 2 may be shut off by closing the outer can steam supply valve 3 during the decompression. .

Next, an embodiment of the operation control method in the steam sterilizer according to the present invention will be described with reference to the drawings.
FIG. 2 is an explanatory view showing each operation process of the first embodiment of the present invention and changes in the steam pressure in the sterilization chamber and the steam jacket in each operation process, and FIG. 3 is an operation process of the second embodiment of the present invention. FIG. 4 is a diagram illustrating changes in steam pressure in the sterilization chamber and the steam jacket in each operation process, and FIG. 4 shows changes in steam pressure in the sterilization chamber and the steam jacket in each operation process and each operation process of the third embodiment of the present invention. FIG. 5 is an explanatory diagram showing each operation process of the fourth embodiment of the present invention and changes in steam pressure in the sterilization chamber and the steam jacket in each operation process.

[First embodiment]
A first embodiment of the present invention will be described with reference to FIG. The operation of the steam sterilizer is started by first operating the power switch to open the shut-off valve 28 and the outer can steam supply valve 3, and steam is supplied to the steam jacket 2 to warm the sterilization chamber 1. . In this warm-up operation, the steam pressure of the steam jacket 2 is increased to a predetermined pressure (50 kPaG to 100 kPaG), the warm-up operation is terminated, and the process proceeds to a standby process.

  When sterilizing an object to be sterilized, the object to be sterilized is accommodated in the sterilization chamber 1, the door (not shown) that seals the sterilization chamber 1 is closed and sealed, and the start switch is operated to operate the sterilization operation. Is started. When the preheating process is set, the object to be sterilized is preheated, and the process including the air exhausting process, the steaming process, the sterilizing process, the steaming process, and the drying process is controlled by the controller 27. Is called.

  In this example, during the above-described operation, the warm-up operation is terminated when the vapor pressure of the steam jacket 2 rises to a predetermined pressure, and after the warm-up operation, the outer can steam supply valve is started until the sterilization operation is started. 3 is closed and steam supply to the steam jacket 2 is shut off. Also, after the sterilization operation is completed and until the next sterilization operation is started, the outer can feed valve 3 is closed to supply steam to the steam jacket 2. It is a standby process to shut off.

  This example will be described in detail. First, by operating a power switch at the time of startup, the shutoff valve 28 and the outer can steam supply valve 3 are opened, steam is supplied to the steam jacket 2, and warm-up for warming the sterilization chamber 1 is performed. Driving is performed. In this example, the warm-up operation increases the vapor pressure of the vapor jacket 2 to 100 kPaG. When the outer can pressure sensor 26 detects that the steam pressure of the steam jacket 2 has increased to 100 kPaG, the controller 27 controls the can steaming of the outer can steaming valve 3 based on the detection signal from the outer can pressure sensor 26. The valve 6 is closed, the warm-up operation is finished, and the process proceeds to the standby process. In the standby process, until the sterilization operation is started, the outer can supply valve 3 is closed and the supply of steam to the steam jacket 2 is shut off.

  When the sterilization operation is started, first, when the preheating process is set, the preheating process is performed. Even if the sterilization operation is started, the outer can steam supply valve 3 is kept closed in the preheating process. Then, the exhaust valve 23 is closed and the air supply valve 9 is closed, and the object to be sterilized is heated by radiant heat from the steam jacket 2 for a preset time. In the preheating process, the heat of the steam jacket 2 warmed by the warm-up operation is used. However, if necessary, the outer can feed valve 4 may be opened and controlled to a predetermined pressure. In starting the sterilization operation, the steam pressure of the steam jacket 2 is preferably 50 kPaG or more.

When the preheating process is up, the process moves to the air exclusion process. The air exclusion process in FIG. 2 is performed as follows.
First, the exhaust steam valve 23 is opened, the inner can steam supply valve 6 is opened, and the process of circulating steam into the sterilization chamber 1 is performed for a set time, and then (1) the exhaust steam valve 23 and the inner can steam supply valve 6 is closed, the vacuum exhaust valve 13 is opened, the vacuum pump 14 is operated, and the inside of the sterilization chamber 1 is depressurized to the set pressure. Next, (2) the vacuum pump 14 is stopped, the vacuum exhaust valve 13 is closed, the inner can steaming valve 6 is opened, and the pressure in the sterilization chamber 1 detected by the inner can pressure sensor 25 becomes atmospheric pressure. Steaming is performed and the inner can steaming valve 6 is closed. These (1) and (2) are repeated a plurality of times.

  (1) and (2) are repeated a plurality of times, and then after (1) is performed, steam is supplied into the sterilization chamber 1 and pressurized until a saturated steam pressure approximately equal to the set sterilization temperature is reached ( Immediately thereafter, the inner steam supply valve 6 is closed, the exhaust steam valve 23 is opened, and the inside of the sterilization chamber 1 is rapidly depressurized to atmospheric pressure. The steam jacket 2 is controlled as follows according to the pressure change in the sterilization chamber 1. Since the pressure in the sterilization chamber 1 does not exceed atmospheric pressure during the operations (1) and (2), the pressure in the steam jacket 2 only needs to be greater than atmospheric pressure. When the warm-up operation is completed and the sterilization operation is performed after the standby process, the pressure in the steam jacket 2 is equal to or higher than the atmospheric pressure, and thus the outer can feed valve 3 remains closed.

  Next, when the operation proceeds to the pressurization pulse, the inside of the sterilization chamber 1 is pressurized to atmospheric pressure or higher, so the outer can feed valve 3 is opened and steam is supplied into the steam jacket 2. The pressure in the steam jacket 2 is slightly higher than the saturated steam pressure at which the sterilization temperature is set, for example, 137.3 ° C. (saturated steam pressure 233.7 kPaG) when the sterilization temperature is set to 135 ° C. Boosted. When the set pressure of the outer can pressure sensor 26 is reached, the outer can feed valve 3 is controlled to be within the set pressure ± 5 kPaG.

  In addition, when the pressure rise in the steam jacket 2 is slower than the pressure rise in the sterilization chamber 1 at the time of the pressurization pulse transition, the inner can feed valve 6 is temporarily closed to It is only necessary to temporarily stop the steaming or to set the timing of the opening operation of the outer can steaming valve 3 earlier so that the pressure in the steam jacket 2 rises first.

  When the air exclusion process ends, the process proceeds to the steaming process. The steaming step is a step of increasing the saturated steam temperature by steam-pressurizing the interior of the sterilization chamber 1 so as to obtain a desired sterilization temperature. In this process, the pressure in the steam jacket 2 is already controlled to be higher than the pressure in the sterilization chamber 1.

  When the temperature in the sterilization chamber 1 rises to a desired temperature, the process proceeds to the sterilization process. The sterilization step is a step of maintaining the inside of the sterilization chamber 1 at a desired temperature for a predetermined time. In this sterilization step, the steam jacket 2 controls the outer can steam supply valve 3 based on the temperature detected by the inner can temperature sensor 30 so that the pressure in the steam jacket 2 ≧ the pressure in the sterilization chamber 1.

  When the sterilization process is completed, the steam in the sterilization chamber 1 is discharged (exhaust process) and the process proceeds to the drying process. In the drying process, the water in the sterilized object is evaporated and dried by boiling under reduced pressure, so that the pressure in the sterilization chamber 1 becomes atmospheric pressure or lower. The exhaust valve 23 is closed, the vacuum exhaust valve 13 is opened, and the vacuum pump 14 is operated to depressurize the sterilization chamber 1 to a set pressure. Next, the vacuum exhaust valve 13 is closed, the vacuum pump 14 is stopped, the air supply valve 9 is opened, air is introduced to atmospheric pressure, and the pressure is restored. In the drying process, the decompression and decompression operations are repeated for a set time. Alternatively, during the set time, the vacuum exhaust valve 13 may be opened and the vacuum pump 14 may be operated to continue the decompression in the sterilization chamber 1. Radiant heat from the steam jacket 2 is necessary to increase the effect of drying the sterilized material. For this reason, the outer can steaming valve 3 is controlled based on the detected pressure of the outer can pressure sensor 26 so that the pressure in the steam jacket 2 is maintained at the same pressure as in the sterilization process. This drying process continues for a preset time.

  When the drying process is completed, the vacuum exhaust valve 13 is closed, the vacuum pump 14 is stopped, the air supply valve 9 is opened, and the inside of the sterilization chamber 1 is restored. The sterilization operation ends when the inner can pressure sensor 25 detects atmospheric pressure. Simultaneously with the end of the sterilization operation, the outer can steam supply valve 3 is closed, the steam supply to the steam jacket 2 is shut off, and the process proceeds to a standby process. The shut-off of the outer can feed valve 3, that is, the standby process, continues until the start switch for the next sterilization operation is operated.

  In the operation control of the steam sterilization apparatus of this example described above, the steam supply to the steam jacket 2 is shut off by closing the outer can feed valve 3 for steaming to the steam jacket 2 in the standby process. The heat radiation from the jacket 2 and the piping is reduced, the temperature in the machine room and the adjacent room can be reduced, and the equipment cost and energy cost taken as countermeasures for high temperature can be reduced.

  Of the steps in the sterilization operation, the step of supplying steam to the sterilization chamber 1 is performed by detecting the steam pressure in the steam jacket 2 and the sterilization chamber 1 using the inner can pressure sensor 25 and the outer can pressure sensor 26, and the steam jacket. Since the outer can feed valve 3 is controlled so that the vapor pressure of 2 is higher than the vapor pressure of the sterilization chamber 1, the vapor supplied to the sterilization chamber 1 can be prevented from condensing on the surface of the sterilization chamber 1. . Further, since the outer can steam supply valve 3 is controlled so that the pressure of the steam jacket 2 in the drying process is equal to the pressure of the steam jacket 2 in the sterilization process, the steam to be sterilized in the sterilization chamber 1 from which the steam has been discharged after sterilization. Goods can also be dried well.

[Second Embodiment]
A second embodiment of the present invention will be described with reference to FIG. In this example, as in the first embodiment, when the operation of the steam sterilizer is started, first, the shutoff valve 28 and the outer can steam supply valve 3 are opened by operating the power switch, and steam is supplied to the steam jacket 2. A warming-up operation is performed in which the sterilization chamber 1 is supplied and the sterilization chamber 1 is warmed. When sterilizing an object to be sterilized, a door (not shown) that houses the object to be sterilized and seals the sterilization chamber 1 is omitted. By closing and sealing and operating the start switch, the sterilization operation is started, and when the preheating process is set, the sterilized material is preheated, and then the air exclusion process, the steaming process, and the sterilization process The process consisting of the steaming process and the drying process is controlled by the controller 27.

  In this example, during the above operation, the warm-up operation ends when the vapor pressure of the steam jacket 2 rises to a predetermined upper limit pressure, and after the warm-up operation, the sterilization operation is started until the sterilization operation is started. The valve 3 is closed to shut off the steam supply to the steam jacket 2, and the steam supply to the steam jacket 2 is closed after the sterilization operation is completed until the next sterilization operation is started. When the steam pressure of the steam jacket 2 is detected to be lower than a predetermined lower limit pressure during the standby process, the outer steam supply valve 3 is opened and steam is supplied into the steam jacket 2, and the steam jacket is opened. The steam pressure of the steam jacket 2 is increased to at least a set pressure higher than the predetermined lower limit pressure and lower than the predetermined upper limit pressure, and steam supply to the steam jacket 2 is shut off. In the present embodiment, the predetermined upper limit pressure is 100 kPaG, the predetermined lower limit pressure is 50 kPaG, and the set pressure is 60 kPaG.

  More specifically, first, at the time of start-up, by operating the power switch, the shut-off valve 28 and the outer can steam supply valve 3 are opened, steam is supplied to the steam jacket 2, and warm-up operation for warming the sterilization chamber 1 is performed. Done. In this example, the warm-up operation increases the steam pressure of the steam jacket 2 to a predetermined upper limit pressure of 100 kPaG. When the outer can pressure sensor 26 detects that the steam pressure of the steam jacket 2 has increased to 100 kPaG, the controller 27 controls the can steaming of the outer can steaming valve 3 based on the detection signal from the outer can pressure sensor 26. The valve 6 is closed, the warm-up operation is finished, and the process proceeds to the standby process.

  In the standby process, until the sterilization operation is started, the outer can supply valve 3 is closed and the supply of steam to the steam jacket 2 is shut off, but the outer can pressure for detecting the pressure in the steam jacket 2 When the sensor 26 detects that the steam pressure of the steam jacket 2 has decreased to 50 kPaG, which is a predetermined lower limit pressure, during the standby process, the outer can feed valve 3 is opened under the control of the controller 27, and the steam jacket 2 is opened. The outer can pressure sensor 26 raises the steam pressure of the steam jacket 2 to a set pressure that is at least higher than the predetermined lower limit pressure and lower than the predetermined upper limit pressure, and the steam pressure of the steam jacket 2 becomes the set pressure. When it reaches, the steam supply to the steam jacket 2 is shut off again.

  Since the start of the sterilization operation and the sterilization operation are the same as those of the first embodiment described above, the description of the first embodiment is used. When the sterilization operation is completed, the outer can feed valve 3 is closed at the same time, the steam supply to the steam jacket 2 is shut off, and the process proceeds to the standby process. The standby process continues until the start switch for the next sterilization operation is operated.

In the operation control of the steam sterilization apparatus of this example described above, the outer can pressure sensor 26 that detects the pressure in the steam jacket 2 has decreased to 50 kPaG, the steam pressure of the steam jacket 2 during the standby process, which is a predetermined lower limit pressure. Is detected, steam is supplied into the steam jacket 2 and the steam pressure of the steam jacket 2 is set to be higher than at least a predetermined lower limit pressure of 50 kPaG and lower than a predetermined upper limit pressure of 100 kPaG. Since the pressure is raised to 60 kPaG, during the sterilization operation, the steam jacket 2 is heated to a pressure at which the steam supplied into the sterilization chamber 1 can be set to a temperature at which the surface of the sterilization chamber 1 or the upper part does not condense. Even if the process can be started immediately, the vapor supplied to the sterilization chamber 1 in the process is condensed on the surface of the sterilization chamber. The situation does not occur, also, can be shortened sterilization operation.
When the steam pressure of the steam jacket 2 reaches the set pressure of 60 kPaG, the steam supply to the steam jacket 2 is shut off again, so that the steam used in the steam jacket 2 can be reduced as much as possible. It is possible to reduce the temperature in adjacent rooms, and to reduce the equipment cost and energy cost taken as countermeasures for high temperatures.

[Third embodiment]
A third embodiment of the present invention will be described with reference to FIG. In this example, as in the first embodiment, when the operation of the steam sterilizer is started, first, the shutoff valve 28 and the outer can steam supply valve 3 are opened by operating the power switch, and steam is supplied to the steam jacket 2. A warming-up operation is performed in which the sterilization chamber 1 is supplied and the sterilization chamber 1 is warmed. When sterilizing an object to be sterilized, a door (not shown) that houses the object to be sterilized and seals the sterilization chamber 1 is omitted. By closing and sealing and operating the start switch, the sterilization operation is started, and when the preheating process is set, the sterilized material is preheated, and then the air exclusion process, the steaming process, and the sterilization process The process consisting of the steaming process and the drying process is controlled by the controller 27.

  In this example, as in the first embodiment described above, during the operation, the warm-up operation is terminated when the vapor pressure of the steam jacket 2 rises to a predetermined upper limit pressure, and after the warm-up operation is completed, the sterilization operation is performed. Until the start, the outer can steaming valve 3 is closed to shut off steaming to the steam jacket 2, and after the sterilization operation is completed until the next sterilization operation is started, the outer can steaming valve 3 Is closed to block the steam supply to the steam jacket 2.

  In this example, when the steam pressure of the steam jacket 2 at that time is lower than a predetermined lower limit pressure at the start of the sterilization operation, the sterilization operation is not started, and steam is supplied into the steam jacket 2 so that the steam jacket 2 When the steam pressure rises to a predetermined lower limit pressure, the steam supply to the steam jacket 2 is shut off and at the same time the sterilization operation is started. Even in this example, the predetermined upper limit pressure is set to 100 kPaG and the predetermined lower limit pressure is set to 50 kPaG, as in the second embodiment.

  This example will be described in detail. First, by operating a power switch at the time of startup, the shutoff valve 28 and the outer can steam supply valve 3 are opened, steam is supplied to the steam jacket 2, and warm-up for warming the sterilization chamber 1 is performed. Driving is performed. In this example, the warm-up operation increases the vapor pressure of the vapor jacket 2 to 100 kPaG. When the outer can pressure sensor 26 detects that the steam pressure of the steam jacket 2 has increased to 100 kPaG, the controller 27 controls the can steaming of the outer can steaming valve 3 based on the detection signal from the outer can pressure sensor 26. The valve 6 is closed, the warm-up operation is finished, and the process proceeds to the standby process. In the standby process, until the sterilization operation is started, the outer can supply valve 3 is closed and the supply of steam to the steam jacket 2 is shut off.

  When starting the sterilization operation, when the sterilization operation start switch is operated, if the outer can pressure sensor 26 detects that the vapor pressure of the steam jacket 2 is lower than 50 kPaG, the sterilization operation is not started. Controlled by the controller 27, the outer can steaming valve 3 is opened, steamed into the steam jacket 2, and the outer can pressure sensor 26 detects that the steam pressure in the steam jacket 2 has risen to 50 kPaG. When the can steaming valve 3 is closed and steaming to the steam jacket 2 is shut off, the sterilization operation starts. First, when the preheating process is set, the preheating process is performed.

  When the preheating process is timed up, an air exclusion process is performed. The air exclusion process is performed as follows. First, the exhaust steam valve 23 is opened, the inner can steam supply valve 6 is opened, and the process of circulating steam into the sterilization chamber 1 is performed for a set time, and then (1) the exhaust steam valve 23 and the inner can steam supply valve 6 is closed, the vacuum exhaust valve 13 is opened, the vacuum pump 14 is operated, and the inside of the sterilization chamber 1 is depressurized to the set pressure. Next, (2) the vacuum pump 14 is stopped, the vacuum exhaust valve 13 is closed, the inner can steaming valve 6 is opened, and the pressure in the sterilization chamber 1 detected by the inner can pressure sensor 25 is set pressure (atmospheric pressure). Steam is supplied until the above is reached, and the inner can supply valve 6 is closed.

  These operations (1) and (2) are repeated a plurality of times. At this time, the pressure in the steam jacket 2 is controlled to be always higher than the detected pressure in the sterilization chamber 1. Specifically, in the operation (1), the pressure in the sterilization chamber 1 is equal to or lower than atmospheric pressure, that is, equal to or lower than 100 ° C., so the outer can feed valve 3 is kept closed. Next, when the operation proceeds to the operation (2), the outer can steam supply valve 3 is opened, and the pressure in the steam jacket 2 detected by the outer can pressure sensor 26 is surely higher than the detected pressure of the inner can pressure sensor 25. The outer can steam supply valve 3 is controlled so as to be higher than the pressure in 1. Again, when the control shifts to (1), the pressure in the sterilization chamber 1 becomes low, so the outer can feed valve 3 is shut off. In addition, when the pressure in the sterilization chamber 1 starts to rise, the increase in the pressure in the steam jacket 2 is delayed, so that the pressure in the sterilization chamber 1> the pressure in the steam jacket 2 does not become so. May be set so as to operate earlier than the timing when the inner can feed valve 6 opens.

  When the air exclusion process is completed, the process proceeds to the steaming process, and the above processes are sequentially performed. Since the sterilization operation of the steaming process transition is the same as the first embodiment described above, the description of the first embodiment is used. When the sterilization operation is completed, the outer can feed valve 3 is closed at the same time, the steam supply to the steam jacket 2 is shut off, and the process proceeds to the standby process. The standby process continues until the start switch for the next sterilization operation is operated.

  In the operation control of the steam sterilization apparatus of this example described above, the steam supply to the steam jacket 2 is shut off by closing the outer can feed valve 3 for steaming to the steam jacket 2 in the standby process. The heat radiation from the jacket 2 and the piping is reduced, the temperature in the machine room and the adjacent room can be reduced, and the equipment cost and energy cost taken as countermeasures for high temperature can be reduced.

  When the sterilization operation is started, if the vapor pressure of the steam jacket 2 at that time is lower than 50 kPaG set as the predetermined lower limit pressure, the sterilization operation is not started and steam is supplied into the steam jacket 2 to When the steam pressure of the jacket 2 rises to 50 kPaG, the steam supply to the steam jacket 2 is shut off and at the same time the sterilization operation starts. Therefore, during the sterilization operation, the steam jacket 2 was supplied into the sterilization chamber 1 in the preheating process. The steam can be raised in a short time to a pressure at which the steam can be brought to a temperature that does not condense on the surface or upper part of the sterilization chamber 1, and even if the process is started immediately, the steam supplied to the sterilization chamber 1 in the process is sterilized. The situation of condensation on the surface of the chamber 1 does not occur, and the sterilization operation can be shortened.

1. 1. Sterilization chamber 2. Steam jacket Outer can steaming valve4. 4. Outer can steaming route Inner can steaming route6. Inner can steaming valve7. Air supply path 8. 8. Air filter Supply valve 10. Check valve 11. Inner can exhaust passage 12. Outer can steaming path 13. Vacuum exhaust valve 14. Vacuum pump 15. Check valve 16. Check valve 17. Outer can steam trap 18. Check valve 19. Drain discharge path 20. Steam discharge path 21. Inner can steam trap 22. Check valve 23. Fumigation valve 24. Check valve 25. Inner can pressure sensor 26. Outer pressure sensor 27. Controller 28. Shut-off valve 29. Check valve 30. Inner can temperature sensor

Claims (6)

A warm-up operation for heating the sterilization chamber by steaming to the steam jacket and, if necessary, the sterilization chamber at the time of start-up, a preheating step for heating an object to be sterilized by heat from the steam jacket, An air evacuation process for excluding air, a steaming process for steaming to a saturated steam pressure at a temperature set in the sterilization chamber, a sterilization process for maintaining the sterilization chamber at a set temperature for a predetermined time, and steam in the sterilization chamber after sterilization A steam sterilization apparatus that performs a sterilization operation including a process comprising a steaming process for discharging the sterilization chamber and a drying process for drying an object to be sterilized,
An outer can steaming valve for steaming the steam jacket from the end of the warm-up operation to the start of the first sterilization operation and from the completion of the sterilization operation to the start of the next sterilization operation. A steam sterilization apparatus comprising control means for closing and shutting off steam supply to the steam jacket. A warm-up operation for heating the sterilization chamber by steaming to the steam jacket and, if necessary, the sterilization chamber at the time of start-up, a preheating step for heating an object to be sterilized by heat from the steam jacket, An air evacuation process for excluding air, a steaming process for steaming to a saturated steam pressure at a temperature set in the sterilization chamber, a sterilization process for maintaining the sterilization chamber at a set temperature for a predetermined time, and steam in the sterilization chamber after sterilization An operation control method in a steam sterilization apparatus for performing a sterilization operation including a process comprising a steaming process for discharging the sterilization chamber and a drying process for drying an object to be sterilized,
The waiting process is from the end of the warm-up operation to the start of the first sterilization operation and from the completion of the sterilization operation to the start of the next sterilization operation, and in the waiting process, the steam jacket is supplied. An operation control method for a steam sterilization apparatus, wherein the steam supply to the steam jacket is shut off by closing a steaming outer can feed valve.   An inner can pressure sensor for detecting the pressure in the sterilization chamber and an outer can pressure sensor for detecting the pressure in the steam jacket are provided, and among the steps in the sterilization operation, the step of supplying steam to the sterilization chamber includes the inner can The steam pressure of the steam jacket and the sterilization chamber is detected by a pressure sensor and an outer can pressure sensor, and the steam supply valve of the steam jacket is controlled to be higher than the steam pressure of the sterilization chamber. 3. The steam sterilization according to claim 2, wherein the outer can steam supply valve is controlled so that the pressure of the steam jacket in the drying step is equal to the pressure of the steam jacket in the sterilization step. Device operation control method.   In the standby step, when the steam pressure of the steam jacket drops below a predetermined pressure during the standby step, the outer can steaming is performed such that steam is supplied into the steam jacket and the steam pressure of the steam jacket is increased to at least a predetermined pressure. The operation control method of the steam sterilizer according to claim 2 or 3, wherein the valve is controlled.   In the sterilization operation, if the steam pressure of the steam jacket has not risen to a predetermined pressure or higher, the process is not started, and the outer can steam supply valve is controlled so as to steam the steam jacket, and the steam 4. The operation control method for a steam sterilizer according to claim 2, wherein the step is started after the steam pressure of the jacket becomes equal to or higher than a predetermined pressure.   The air exhausting step alternately performs depressurization and steaming in the sterilization chamber, and closes the outer can steaming valve and shuts off steaming to the steam jacket during decompression. The operation control method of the steam sterilizer according to any one of 2 to 5.

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