JP6999188B2 - Heat sterilizer - Google Patents

Description

The present invention relates to a heat sterilizer for heat sterilizing an object to be sterilized by sealing and packaging foods such as retort pouches, air-impregnated containers, bottles and canned foods.

Conventional heat sterilizers are described in Patent Documents 1, 2 and 3. The heat sterilizer of Patent Document 1 heats and sterilizes the object to be sterilized contained in the sterilization tank with steam, and when the object to be sterilized is cooled after sterilization, the inside of the sterilization tank is filled with cooling water. .. The heat sterilizer of Patent Document 2 heats and sterilizes the object to be sterilized contained in the sterilization tank with steam, and when the object to be sterilized is cooled after sterilization, cooling water is cooled from above with respect to the object to be sterilized. Is sprinkled. The heat sterilizer of Patent Document 3 heats and sterilizes the object to be sterilized contained in the sterilization tank with hot water, and when the object to be sterilized is cooled after sterilization, it is viewed from the side with respect to the object to be sterilized. Cooling water is sprayed.

Japanese Unexamined Patent Publication No. 2004-129635 Japanese Unexamined Patent Publication No. 10-295343 Jikkai Sho 63-165195

However, the heat sterilizer of Patent Document 1 has a problem that a large amount of cooling water is required in the cooling step because the inside of the sterilizing tank is filled with cooling water when the object to be sterilized is cooled. In the heat sterilizer of Patent Document 2, when the object to be sterilized is cooled, the cooling water is sprinkled on the object to be sterilized from above, so that it is difficult to evenly cool the entire object to be sterilized. .. In the heat sterilizer of Patent Document 3, since the spray portion for injecting cooling water is provided on the side of the tray inside the inner surface of the sterilizer tank, it is difficult to increase the size of the tray and at the same time sterilize. The number of objects to be sterilized was small.

The present invention has been made to deal with the above problems, and an object of the present invention is to provide a heat sterilizer capable of simultaneously sterilizing many objects to be sterilized and evenly cooling with a small amount of cooling water.

In order to achieve the above object, the features of the heat sterilizer according to the present invention are a sterilization tank for accommodating the sterilized object, a tray horizontally arranged inside the sterilizer tank to support the sterilized object, and the above. The heating means is provided with a heating means for heating the object to be sterilized and a cooling means for cooling the object to be sterilized. The heating means has a steam supply pipe for supplying steam to the inside of the sterilization tank, and the cooling means. Has a plurality of fountain nozzles for injecting cooling water into the sterilization tank, a plurality of nozzle mounting portions having a mounting surface to which the fountain nozzle is mounted, and a water supply pipe for supplying the cooling water to the fountain nozzle. At least a part of the mounting surface of the at least one nozzle mounting portion is arranged outside the inner surface of the sterilizing tank so as to face the opening provided on the inner surface of the sterilizing tank. A wall portion for preventing leakage of water vapor is provided between the outer peripheral portion of the mounting surface facing the opening and the inner peripheral portion of the opening , and is mounted on the mounting surface facing the opening. The injection port of the fountain nozzle is arranged outside the inner surface of the sterilizer tank, and the inner surface of the wall portion expands toward the opening to the extent that the injection angle of the fountain nozzle can be effectively secured. It is formed in a conical shape .

In this configuration, at least a part of the mounting surface of at least one nozzle mounting portion is arranged outside the inner surface of the sterilizing tank so as to face the opening provided on the inner surface of the sterilizing tank. The portion protruding inward from the inner surface of the sterilizer tank becomes smaller. Therefore, as compared with the heat sterilizer described in Patent Document 3, a larger tray can be used, and at the same time, the number of objects to be sterilized can be increased .

Further , the leakage of water vapor can be prevented by the wall portion provided between the outer peripheral portion of the mounting surface facing the opening and the inner peripheral portion of the opening. Further, since the object to be sterilized is cooled by injecting cooling water from a plurality of fountain nozzles, it is possible to cool evenly with a small amount of cooling water.

Since the injection port of the fountain nozzle mounted on the mounting surface facing the opening is arranged outside the inner surface of the sterilization tank, the fountain nozzle does not protrude inward from the inner surface of the sterilization tank. Therefore, it is possible to use a larger tray and at the same time increase the number of objects to be sterilized. Further, since the inner surface of the wall portion is formed in a conical shape that spreads toward the opening to the extent that the injection angle of the fountain nozzle can be effectively secured, the cooling water ejected from the fountain nozzle is formed in the inner peripheral portion of the opening. Can be prevented from hitting.

Another feature of the heat sterilizer according to the present invention is that the sterilizer has a cylindrical main body having a axis extending in the horizontal direction, and the plurality of jet nozzles are in a direction parallel to the tray. Moreover, the opening is provided so as to face the axis in a direction orthogonal to the axis, and the opening facing the mounting surface is provided at a position separated from the axis upward or downward.

The width of the cylindrical sterilizer tank is widest in the central part in the vertical direction, and narrows as it is separated upward or downward from the axis. In the above configuration, the opening facing the mounting surface is provided at a position separated upward or downward from the shaft, so that the fountain nozzle is retracted from the inside of the sterilizing tank in the portion where the width of the sterilizing tank is narrowed. Can be done. This makes it possible to efficiently secure the installation space for the tray.

Another feature of the heat sterilizer according to the present invention is that the heating means is piped by branching from the water supply pipe, and the water heated inside the sterilization tank is supplied to the water supply pipe as heating water. , It is possible to switch between a cooling pipeline through which the cooling water is passed through the water supply pipe and supplied to the fountain nozzle and a heating pipeline through which the heated water is passed through the hot water pipe and the water supply pipe and supplied to the fountain nozzle. It is to have a pipeline switching means configured in.

In this configuration, heated water can be injected from the fountain nozzle by selecting the heating pipeline with the pipeline switching means. That is, the heating means has a function of sterilizing the object to be sterilized with steam and a function of sterilizing the object to be sterilized with heated water. The operator can operate the heat sterilization device by switching between the steam sterilization operation using steam and the spray sterilization operation using heated water.

Another feature of the heat sterilizer according to the present invention is a compressed air supply means for supplying compressed air to the inside of the sterilization tank, and the compressed air supply means is a compressed air supply pipe communicating with the inside of the sterilization tank. To have.

In this configuration, the pressure inside the sterilizer tank, that is, the pressure outside the object to be sterilized (external pressure) can be adjusted with compressed air, so even if the pressure inside the object to be sterilized (internal pressure) increases during the heat sterilization process. , The external pressure can be made higher than the internal pressure, and the sterilized object can be prevented from bursting.

Another feature of the heat sterilization apparatus according to the present invention is an exhaust means for discharging air and water vapor inside the sterilization tank, and a drainage means for discharging water inside the sterilization tank. It has a first exhaust pipe communicating with the inside of the sterilization tank and a first on-off valve for opening and closing the pipeline of the first exhaust pipe, and the drainage means is drainage communicating with the inside of the sterilization tank. It is to have a pipe and a second on-off valve for opening and closing the pipeline of the drainage pipe.

In this configuration, the air, water vapor and water inside the sterilization tank can be discharged as needed.

Another feature of the heat sterilizer according to the present invention is that the exhaust means has a second exhaust pipe communicating with the inside of the sterilizer tank and an exhaust control valve for adjusting the exhaust flow rate of the second exhaust pipe. It is in the fact that it is.

In this configuration, even when the pipe of the first exhaust pipe is closed, air and water vapor can be discharged from the pipe of the second exhaust pipe, so that the flow of air and water vapor is always generated inside the sterilization tank. Can be done. As a result, the temperature inside the sterilization tank can be made uniform, and the pressure fluctuation inside the sterilization tank can be alleviated. Further, by adjusting the exhaust flow rate of the second exhaust pipe with the exhaust control valve, the flow of air and water vapor can be appropriately maintained.

Another feature of the heat sterilizer according to the present invention is a cooler for cooling a mixture of the air, the steam and the water discharged from the exhaust means and the drainage means, and the cooler is the mixing. Two sealing portions that seal the gap between the inner tube through which the body passes, the outer tube provided on the outside of the inner tube, and the gap between the inner surface of the outer tube and the outer surface of the inner tube at both ends of the outer tube. It has a first water supply port provided on the pipe wall of the outer pipe and a second water supply port provided on the pipe wall of the inner pipe between the two sealing portions. 2 The water supply port is provided on the upstream side of the flow of the mixture flowing through the inner pipe with respect to the first water supply port.

In this configuration, the mixture can be cooled by a cooler, so that even when the mixture is discharged into the atmosphere in order to suppress pressure fluctuations in the sterilization tank, problems due to waste heat are unlikely to occur.

It is a front view which shows typically the structure of the heat sterilization apparatus which concerns on a reference example . It is sectional drawing which shows typically the structure of the heat sterilization apparatus which concerns on a reference example . It is a block diagram which shows the structure of the control system of a heat sterilizer. It is a figure which shows the mounting structure of the fountain nozzle in the heat sterilization apparatus of FIG. 1, (A) is a sectional view, (B) is a side view. It is sectional drawing which shows the structure of a cooler. It is a flow chart which shows the control operation of the steam sterilization operation by a control part. It is a flow chart which shows the control operation of a spray sterilization operation by a control part. It is a front view which shows typically the structure of the heat sterilization apparatus which concerns on embodiment of this invention . 8 is a view showing a mounting structure of a fountain nozzle in the heat sterilizer of FIG. 8, where FIG. 8A is a cross-sectional view and FIG. 8B is a side view.

Hereinafter, a reference example of the heat sterilizer according to the present invention will be described with reference to the drawings. FIG. 1 is a front view schematically showing the configuration of the heat sterilizer 10 according to the reference example . FIG. 2 is a cross-sectional view schematically showing the configuration of the heat sterilizer 10. FIG. 3 is a block diagram showing the configuration of the control system 28 of the heat sterilizer 10. 4A and 4B are views showing a mounting structure of fountain nozzles 68a to 68f in the heat sterilizer 10, where FIG. 4A is a cross-sectional view and FIG. 4B is a side view. FIG. 5 is a vertical sectional view showing the configuration of the cooler 26. The "up / down / front / back" directions used in the following description correspond to these directions indicated by the arrows in FIG. Further, each direction of "up, down, left, right" used in the following description coincides with these directions indicated by arrows in FIG.

(Structure of heat sterilizer 10)
As shown in FIG. 1, the heat sterilizer 10 heats and sterilizes an object X to be sterilized in which food or the like is hermetically sealed, and includes a sterilizer tank 12, a plurality of trays 14 (six in this reference example ), and cooling means. 16 and heating means 18 are provided. Further, the heat sterilizer 10 includes a compressed air supply means 20, an exhaust means 22, a drainage means 24, and a cooler 26.

As shown in FIG. 3, the control system 28 of the heat sterilizer 10 has a control unit 30 and a first on-off valve 32a, a second on-off valve 32b, a third on-off valve 32c, and a fourth on-off valve controlled by the control unit 30. It includes a valve 32d, a fifth on-off valve 32e, a sixth on-off valve 32f, a pump 34, and a three-way valve 36. Further, the control system 28 includes an operation panel 38, a timer 40, a temperature sensor 42, a pressure sensor 44, a first level sensor 46a and a second level sensor 46b that give information necessary for control to the control unit 30. ..

If these are named based on the type of gas or liquid that is shut off by the on-off valves 32a to 32f, the first on-off valve 32a is the "exhaust valve" and the second on-off valve 32b is the "drain valve". 3 The on-off valve 32c is a "steam valve". Further, the fourth on-off valve 32d is a "water supply valve", the fifth on-off valve 32e is a "compressed air valve", and the sixth on-off valve 32f is a "cold water valve".

As shown in FIG. 1, the sterilization tank 12 accommodates the object to be sterilized X and has a cylindrical main body portion 50 having a axis P extending in the horizontal direction. One axial end (rear end) of the main body 50 is closed by a closing plate 52, and an opening 54 is formed at the other axial end (front end) of the main body 50. A disk-shaped lid 56 is attached to the opening 54 so as to be openable and closable.

An exhaust port 58 for discharging air and water vapor inside the sterilization tank 12 is provided in the upper part of the sterilization tank 12, and a drainage pit 60 for storing water inside the sterilization tank 12 is provided in the lower part of the sterilization tank 12. It is provided. The drainage pit 60 is provided with a drainage port 62 for draining the water stored therein.

Further, above the sterilization tank 12, a temperature sensor 42 for detecting the temperature inside the sterilization tank 12 and a pressure sensor 44 for detecting the pressure inside the sterilization tank 12 are provided. A first level sensor 46a for detecting that the water level has been set in advance and reached the upper limit of the set range is provided in the lower part of the sterilization tank 12, and the water level reaches the lower limit of the set range in the drainage pit 60. A second level sensor 46b is provided to detect the fact that the sensor has been used. Further, as shown in FIG. 2, a plurality of support portions 64 (six in this reference example ) for supporting the tray 14 are provided inside the sterilization tank 12 at intervals in the vertical direction.

As shown in FIG. 2, a plurality of (six in this reference example ) openings 70a to 70f for attaching the fountain nozzles 68a to 68f are provided on the inner surface 66a of the peripheral wall portion 66 constituting the sterilization tank 12. There is. In this reference example , three openings 70a, 70b, 70c are provided on one side (right side) in the horizontal direction across the axis P of the sterilization tank 12 at intervals in the circumferential direction, and the sterilization tank 12 is provided. Three openings 70d, 70e, and 70f are provided on the other side (left side) in the horizontal direction across the shaft P at intervals in the circumferential direction. The openings 70a, 70b, 70c on one side (right side) are arranged so as to correspond to the rear portion of the tray 14. The openings 70d, 70e, 70f on the other side (left side) correspond to the front portion of the tray 14, and are arranged so as to be vertically offset from the openings 70a, 70b, 70c on the one side.

As shown in FIG. 2, the tray 14 supports the object X to be sterilized inside the sterilizer tank 12, and is formed in a rectangular plate shape in a plan view. The support portion 64 has a pair of support pieces 64a and 64b extending parallel to the axis P (in the front-rear direction), and two side ends of the tray 14 are placed on the support pieces 64a and 64b. There is.

As shown in FIG. 2, the cooling means 16 cools the object X to be sterilized, and a plurality of fountain nozzles 68a to 68f for injecting cooling water into the sterilization tank 12 and fountain nozzles 68a to 68f are attached. A plurality of nozzle mounting portions 74a to 74f having mounting surfaces 72a to 72f, a water supply pipe 76 for supplying cooling water to the fountain nozzles 68a to 68f, and a fourth on-off valve 32d for opening and closing the pipeline of the water supply pipe 76. It has a pump 34 provided in the water supply pipe 76.

Hereinafter, the configurations of the nozzle mounting portions 74a to 74f shown in FIG. 2 will be described by taking the nozzle mounting portion 74a as an example. As shown in FIGS. 4A and 4B, the nozzle mounting portion 74a has a cylindrical main body portion 78. A first female screw portion 78a is provided at one end of the main body 78, and a second female screw 78b is provided at the other end of the main body 78. A water supply pipe 76 is connected to the first female threaded portion 78a via a joint 80, and the male threaded portion 82 of the fountain nozzle 68a is screwed into the second female threaded portion 78b. In FIGS. 4A and 4B, the fountain nozzle 68a is shown by a virtual line (dashed-dotted line).

A cylindrical wall portion 84 projecting in the axial direction of the main body portion 78 is provided on the end surface, that is, the mounting surface 72a in which the second female screw portion 78b of the main body portion 78 is opened, and the outer peripheral portion of the wall portion 84 is provided. , Is joined to the inner peripheral portion of the opening 70a by a joining means such as welding. That is, the mounting surface 72a is arranged outside the inner surface 66a of the sterilizing tank 12 facing the opening 70a, and water vapor is placed between the outer peripheral portion of the mounting surface 72a and the inner peripheral portion of the opening 70a. A wall portion 84 is provided to prevent leakage. The portion of the wall portion 84 that protrudes inward from the inner surface 66a of the sterilizer tank 12 is excised.

As shown in FIG. 2, in a state where the outer peripheral portion of the wall portion 84 is joined to the inner peripheral portion of the opening portion 70a, the mounting surface 72a is parallel to the tray 14 and orthogonal to the axis P. It is arranged toward. Therefore, the fountain nozzle 68a mounted on the mounting surface 72a is directed in the direction parallel to the tray 14 and in the direction orthogonal to the axis P.

In the heat sterilizer 10 , "at least a part of the mounting surface of at least one nozzle mounting portion is arranged outside the inner surface of the sterilizing tank so as to face the opening provided on the inner surface of the sterilizing tank." It is characterized by. In order to satisfy this feature, the entire mounting surfaces 72a and 72f of the nozzle mounting portions 74a and 74f shown in FIG. 2 are arranged outside the inner surface 66a of the sterilizing tank 12 facing the openings 70a and 70f. Further, a part of the mounting surface 72c of the nozzle mounting portion 74c shown in FIG. 2 faces the opening 70c and is arranged outside the inner surface 66a of the sterilizing tank 12.

Further, in the nozzle mounting portions 74b, 74d, 74e, since the mounting surfaces 72b, 72d, 72e are arranged inside the inner surface 66a of the sterilizer tank 12, the outer peripheral portion of the main body portion 78 has openings 70b, 70d, 70e. It is joined to the inner circumference of the. In the nozzle mounting portion 74c, a part of the mounting surface 72c is arranged inside the inner surface 66a of the sterilizer tank 12, so that a part of the outer peripheral portion of the main body portion 78 is joined to the inner peripheral portion of the opening 70c. There is.

The openings 70a, 70f, 70c facing the mounting surfaces 72a, 72f, 72c are provided at positions separated upward or downward from the shaft P. Further, the three fountain nozzles 68a, 68b, 68c on one side (right side) and the three fountain nozzles 68d, 68e, 68f on the other side (left side) sandwiching the axis P from the horizontal direction are arranged linearly in the vertical direction. It is arranged in.

As shown in FIG. 1, the heating means 18 heats the object X to be sterilized, and opens and closes the steam supply pipe 86 for supplying steam to the inside of the sterilization tank 12 and the pipeline of the steam supply pipe 86. It has 3 on-off valves 32c. The steam injection port 86a of the steam supply pipe 86 is arranged in the lower part of the internal space of the sterilization tank 12. Further, the heating means 18 includes a water supply pipe 76, a hot water pipe 88 that is branched from the water supply pipe 76 and is piped, and the water heated inside the sterilization tank 12 is supplied to the water supply pipe 76 as heating water, and a three-way valve 36. have. The upstream end of the hot water pipe 88 is connected to the drain port 62 and communicates with the inside of the sterilization tank 12, and the downstream end of the hot water pipe 88 is connected to the water supply pipe 76 via the three-way valve 36. It is connected.

The three-way valve 36 functions as a "pipeline switching means", and supplies the cooling pipe line 92 for supplying cooling water to the fountain nozzles 68a to 68f through the water supply pipe 76, and the hot water pipe 88 and the water supply pipe for heating water. It is configured to be switchable from the heating pipeline 94 that is passed through the 76 and supplied to the fountain nozzles 68a to 68f.

As shown in FIG. 1, the compressed air supply means 20 supplies compressed air to the inside of the sterilization tank 12, and the compressed air supply pipe 96 communicating with the inside of the sterilization tank 12 via the steam supply pipe 86. It also has a fifth on-off valve 32e that opens and closes the line of the compressed air supply pipe 96. In this reference example , the compressed air supply pipe 96 is provided by branching from the steam supply pipe 86, and on the downstream side of the branch portion, the compressed air is passed through the steam supply pipe 86 and supplied to the inside of the sterilization tank 12. ..

As shown in FIG. 1, the exhaust means 22 discharges air and water vapor inside the sterilization tank 12, and is a pipe of a first exhaust pipe 98 and a first exhaust pipe 98 that communicate with the inside of the sterilization tank 12. It has a first on-off valve 32a that opens and closes the road. The upstream end of the first exhaust pipe 98 is connected to the exhaust port 58, and the downstream end of the first exhaust pipe 98 is connected to the cooler 26.

Further, the exhaust means 22 has a second exhaust pipe 100 communicating with the inside of the sterilization tank 12 and an exhaust control valve 102 for adjusting the exhaust flow rate of the second exhaust pipe 100. The second exhaust pipe 100 is branched from the first exhaust pipe 98 and is provided in parallel with the first exhaust pipe 100.

As shown in FIG. 1, the drainage means 24 discharges the water inside the sterilization tank 12, and opens and closes the drainage pipe 104 communicating with the inside of the sterilization tank 12 and the pipeline of the drainage pipe 104. It has an on-off valve 32b. The upstream end of the drain pipe 104 is connected to the drain port 62, and the downstream end of the drain pipe 104 is connected to the cooler 26.

As shown in FIG. 5, the cooler 26 cools a mixture of air, water vapor, and water discharged from the exhaust means 22 and the drainage means 24 shown in FIG. 1, and has an inner pipe 106 through which the mixture is passed. , The outer pipe 108 provided on the outer side of the inner pipe 106, and the two sealing portions 110a and 110b that seal the gap between the inner surface of the outer pipe 108 and the outer surface of the inner pipe 106 at both ends of the outer pipe 108. Have. The inner diameter of the outer pipe 108 is set to be larger than the outer diameter of the inner pipe 106, and the length of the outer pipe 108 is set to be shorter than the length of the inner pipe 106.

Further, the cooler 26 has a first water supply port 112 provided on the pipe wall of the outer pipe 108 and a second water supply port 114 provided on the pipe wall of the inner pipe 106 between the two sealing portions 110a and 110b. And have. The second water supply port 114 of this reference example is a plurality of holes, and is provided on the upstream side of the flow of the mixture flowing through the inner pipe 106 with respect to the first water supply port 112.

Then, as shown in FIG. 1, the upstream end of the inner pipe 106 (FIG. 5) is communicated with the downstream end of the first exhaust pipe 98, the second exhaust pipe 100, and the drain pipe 104. The downstream end of the inner pipe 106 (FIG. 5) is communicated with the atmosphere through an exhaust pipe (not shown). Further, a downstream end of the water supply branch pipe 116 branched from the water supply pipe 76 is connected to the first water supply port 112, and the water supply branch pipe 116 is provided with a sixth on-off valve 32f. Has been done.

The control unit 30 shown in FIG. 3 is a microcomputer including a CPU, a ROM, a RAM, and the like, and the ROM stores control programs for each of the “steam sterilization operation” and the “spray sterilization operation”. The operations of the on-off valves 32a to 32f, the pump 34, and the three-way valve 36 electrically connected to the control unit 30 are controlled according to the control program. As shown in FIG. 1, the control unit 30 is incorporated in a control panel 118 provided independently of the sterilization tank 12.

(Operation of heat sterilizer 10)
FIG. 6 is a flow chart showing a control operation of the “steam sterilization operation” by the control unit 30. FIG. 7 is a flow chart showing a control operation of the “spray sterilization operation” by the control unit 30.

When the object X to be sterilized is heat-sterilized using the heat sterilizer 10 shown in FIGS. 1 and 2, the operator first stores the tray 14 on which the object X to be sterilized is placed inside the sterilization tank 12. .. Subsequently, various operating conditions are input by operating the buttons on the operation panel 38 (FIG. 3), and then the operation start switch on the operation panel 38 is pressed. Here, various operating conditions include control programs such as "steam sterilization operation" and "spray sterilization operation", as well as specific numerical values such as sterilization temperature and sterilization time.

(Control operation of steam sterilization operation)
When the operator presses the operation start switch of the "steam sterilization operation" provided on the operation panel 38 (FIG. 3), the control unit 30 controls each process of steps S1 to S13, that is, ". The "deaeration step", "first temperature rise step", "first sterilization step", "second temperature rise step", "second sterilization step", "cooling step" and "drainage step" are executed.

In the "degassing step" of step S1, the control unit 30 opens the third on-off valve (steam valve) 32c provided in the steam supply pipe 86 and the first on-off valve 32a provided in the first exhaust pipe 98. Open (exhaust valve). Then, steam is supplied to the inside of the sterilization tank 12, and the air inside the sterilization tank 12 is pushed out from the exhaust port 58 by the steam.

In the "first temperature rising step" of step S3, the control unit 30 opens the third on-off valve (steam valve) 32c so as to supply steam to the sterilization tank 12. Further, the control unit 30 is a fifth on-off valve provided in the compressed air supply pipe 96 so that the pressure detected by the pressure sensor 44 (hereinafter referred to as “detection pressure”) is within a preset pressure range. (Compressed air valve) 32e is controlled. That is, the fifth on-off valve (compressed air valve) 32e is opened when the detected pressure becomes lower than the minimum value in the pressure range, and the fifth on-off valve (compressed air valve) 32e is opened when the detected pressure becomes higher than the maximum value in the pressure range. The valve (compressed air valve) 32e is closed. Then, when the temperature inside the sterilizing tank 12 detected by the temperature sensor 42 reaches the preset first temperature, the process proceeds to the next step S5.

In the "first sterilization step" of step S5, the control unit 30 makes a third so that the temperature detected by the temperature sensor 42 (hereinafter referred to as "detection temperature") is within the preset first temperature range. The on-off valve (steam valve) 32c is controlled. That is, when the detection temperature becomes lower than the minimum value in the first temperature range, the third on-off valve (steam valve) 32c is opened, and when the detection temperature becomes higher than the maximum value in the first temperature range. The third on-off valve (steam valve) 32c is closed. Further, the control unit 30 controls the fifth on-off valve (compressed air valve) 32e so that the pressure detected by the pressure sensor 44 (hereinafter, referred to as “detected pressure”) is within a preset pressure range. .. That is, the fifth on-off valve (compressed air valve) 32e is opened when the detected pressure becomes lower than the minimum value in the pressure range, and the fifth on-off valve (compressed air valve) 32e is opened when the detected pressure becomes higher than the maximum value in the pressure range. The valve (compressed air valve) 32e is closed. Then, when the time measured by the timer 40 reaches a preset time, the process proceeds to the next step S7.

In the "second temperature rising step" of step S7, the control unit 30 opens the third on-off valve (steam valve) 32c so as to supply steam to the sterilization tank 12. Further, the control unit 30 is a fifth on-off valve provided in the compressed air supply pipe 96 so that the pressure detected by the pressure sensor 44 (hereinafter referred to as “detection pressure”) is within a preset pressure range. (Compressed air valve) 32e is controlled. That is, the fifth on-off valve (compressed air valve) 32e is opened when the detected pressure becomes lower than the minimum value in the pressure range, and the fifth on-off valve (compressed air valve) 32e is opened when the detected pressure becomes higher than the maximum value in the pressure range. The valve (compressed air valve) 32e is closed. Then, when the temperature inside the sterilizing tank 12 detected by the temperature sensor 42 reaches the preset second temperature, the process proceeds to the next step S9.

In the "second sterilization step" of step S9, the control unit 30 makes a third so that the temperature detected by the temperature sensor 42 (hereinafter referred to as "detection temperature") is within the preset second temperature range. The on-off valve (steam valve) 32c is controlled. That is, when the detection temperature becomes lower than the minimum value in the second temperature range, the third on-off valve (steam valve) 32c is opened, and when the detection temperature becomes higher than the maximum value in the first temperature range. The third on-off valve (steam valve) 32c is closed. Further, the control unit 30 controls the fifth on-off valve (compressed air valve) 32e so that the pressure detected by the pressure sensor 44 (hereinafter, referred to as “detected pressure”) is within a preset pressure range. .. That is, the fifth on-off valve (compressed air valve) 32e is opened when the detected pressure becomes lower than the minimum value in the pressure range, and the fifth on-off valve (compressed air valve) 32e is opened when the detected pressure becomes higher than the maximum value in the pressure range. The valve (compressed air valve) 32e is closed. Then, when the time measured by the timer 40 reaches a preset time, the process proceeds to the next step S11.

In the "cooling step" of step S11, the control unit 30 operates the three-way valve 36 to shut off the pipeline of the hot water pipe 88 and opens the fourth on-off valve (water supply valve) 32d to inject cooling water. It is supplied to the nozzles 68a to 68f. Further, the control unit 30 controls the second on-off valve (drainage valve) 32b so that the water level inside the sterilization tank 12 detected by the level sensors 46a and 46b is within a preset range. That is, the control unit 30 opens the second on-off valve (drainage valve) 32b when the first level sensor 46a detects that the water level in the sterilization tank 12 has reached the upper limit within the set range, and the water level is set. When the second level sensor 46b detects that the lower limit within the range has been reached, the second on-off valve (drainage valve) 32b is closed. Then, when the time measured by the timer 40 reaches a preset time, the process proceeds to the next step S13.

In the "drainage process" of step S13, the control unit 30 opens the first on-off valve 32a (exhaust valve) provided in the first exhaust pipe 98 and the second on-off valve 32b (drainage) provided in the drain pipe 104. Open the valve). Then, the air inside the sterilization tank 12 is exhausted from the exhaust port 58, and the water inside the sterilization tank 12 is drained from the drain port 62.

(Control operation of spray sterilization operation)
When the operator presses the operation start switch of the "spray sterilization operation" provided on the operation panel 38 (FIG. 3), the control unit 30 controls each process of steps S21 to S33, that is, ". The "deaeration step", "first temperature rise step", "first sterilization step", "second temperature rise step", "second sterilization step", "cooling step" and "drainage step" are executed.

The operation of each step in the "spray sterilization operation" shown in FIG. 7 is the operation of each step in the "steam sterilization operation" shown in FIG. 6, except that the heating medium is changed from "steam" to "heated water". Is the same as. That is, in steps S1 to S9 of the "steam sterilization operation" shown in FIG. 6, the control unit 30 opens the third on-off valve (steam valve) 32c with the fourth on-off valve (water supply valve) 32d closed, and steam. Steam is supplied from the supply pipe 86 to the inside of the sterilization tank 12. On the other hand, in steps S21 to S29 of the "spray sterilization operation" shown in FIG. 7, the control unit 30 operates the three-way valve 36 for heating with the fourth on-off valve (water supply valve) 32d open. Pipe line 94 (FIG. 1) is selected, and heated water is sprayed into the sterilization tank 12 from the fountain nozzles 68a to 68f.

(Effect of heat sterilizer 10)
According to this reference example , the following effects can be achieved by the above configuration. That is, as shown in FIG. 4A, at least a part of the mounting surfaces 72a to 72f of at least one nozzle mounting portion 74a to 74f faces the openings 70a to 70f provided in the inner surface 66a of the sterilization tank 12. Since it is arranged outside the inner surface 66a of the sterilization tank 12, the portion of the fountain nozzles 68a to 68f that protrudes inward from the inner surface 66a of the sterilization tank 12 becomes smaller. Therefore, the large tray 14 can be used, and many objects X to be sterilized can be sterilized at the same time.

Further, the wall portion 84 provided between the outer peripheral portion of the mounting surfaces 72a, 72f, 72c facing the openings 70a, 70f, 70c and the inner peripheral portion of the openings 70a, 70f, 70c prevents water vapor leakage. can. Further, since the cooling water is injected from the fountain nozzles 68a to 68f to cool the object X to be sterilized, the object X to be sterilized can be cooled evenly with a small amount of cooling water.

As shown in FIG. 2, the openings 70a, 70f, 70c facing the mounting surfaces 72a, 72f, 72c are provided at positions separated upward or downward from the shaft P. Further, the three fountain nozzles 68a, 68b, 68c on one side (right side) and the three fountain nozzles 68d, 68e, 68f on the other side (left side) sandwiching the axis P from the horizontal direction are arranged linearly in the vertical direction. It is arranged in. Therefore, assuming that a plurality of fountain nozzles are arranged in the vertical direction, the fountain nozzles 68a to 68f have a mounting surface 72a, 72f, 72c as compared with the case where the mounting surfaces 72a, 72f, 72c are arranged inside the inner surface 66a of the sterilization tank 12. The whole can be retracted from the inside of the sterilization tank 12, and a wide space for arranging the tray 14 can be secured.

As shown in FIG. 2, since the openings 70a, 70f, 70c facing the mounting surfaces 72a, 72f, 72c are provided at positions separated from the shaft P upward or downward, the width of the sterilization tank 12 becomes narrow. The fountain nozzles 68a, 68f, 68c can be retracted from the inside of the sterilization tank 12 at the portion. As a result, the installation space for the tray 14 can be efficiently secured.

By selecting the heating pipe line 94 with the three-way valve 36 shown in FIG. 1, the heated water can be injected from the fountain nozzles 68a to 68f. That is, the heating means 18 has not only the function of sterilizing the object X to be sterilized with steam, but also the function of sterilizing the object X to be sterilized with heated water. Therefore, the operator can operate the heat sterilization apparatus 10 by appropriately selecting a steam sterilization operation using steam (FIG. 6) and a spray sterilization operation using heated water (FIG. 7).

Since the pressure inside the sterilizer tank 12 shown in FIG. 1, that is, the pressure outside the object X to be sterilized (external pressure) can be adjusted with compressed air, the pressure inside the object X to be sterilized (internal pressure) becomes high in the process of heat sterilization. Even in this case, the external pressure can be made higher than the internal pressure, and the sterilized object X can be prevented from bursting.

As shown in FIG. 1, the exhaust means 22 has a first exhaust pipe 98 communicating with the inside of the sterilization tank 12 and a first on-off valve (exhaust valve) 32a for opening and closing the pipeline of the first exhaust pipe 98. Since the drainage means 24 has a drainage pipe 104 communicating with the inside of the sterilization tank 12 and a second on-off valve (drainage valve) 32b for opening and closing the pipeline of the drainage pipe 104, the sterilization tank The air, water vapor and water inside the 12 can be discharged as needed.

As shown in FIG. 1, since the second exhaust pipe 100 is provided separately from the first exhaust pipe 98, even if the pipeline of the first exhaust pipe 98 is closed, the pipe of the second exhaust pipe 100 is provided. Air and water vapor can be exhausted from the road. Therefore, the flow of air and water vapor can always be generated inside the sterilization tank. Further, by adjusting the exhaust flow rate of the second exhaust pipe 100 with the exhaust control valve 102, the flow of air and water vapor can be appropriately maintained. As a result, the temperature inside the sterilization tank can be made uniform, and the pressure fluctuation inside the sterilization tank can be alleviated.

In the inventor's experiment, the temperature distribution when the exhaust control valve 102 was completely closed was ± 1 ° C, and the temperature distribution when the exhaust control valve 102 was properly opened was ± 0.5 ° C or less. Further, when the pressure fluctuation when the exhaust control valve 102 was completely closed was 10 Kpa, the pressure fluctuation when the exhaust control valve 102 was properly opened was 5 Kpa or less.

As shown in FIG. 1, since the mixture of air, water vapor, and water discharged from the sterilization tank 12 can be cooled by the cooler 26, the mixture is discharged into the atmosphere in order to suppress the pressure fluctuation of the sterilization tank 12. Even in that case, problems due to waste heat are unlikely to occur. In the inventor's experiment, the temperature of the mixture discharged from the cooler 26 was 50 ° C. or lower. Therefore, even when this mixture is passed through a normal vinyl chloride tube, there is no problem due to waste heat.

In the above reference example , the wall portion 84 shown in FIGS. 4A and 4B is formed by diagonally cutting a cylindrical member, but the method for forming the wall portion 84 is appropriately changed. May be done.

The configuration of the “pipeline switching means” is not limited to the three-way valve 36 shown in FIG. 1, and may be changed as appropriate. For example, instead of the three-way valve 36, two on-off valves (not shown) for opening and closing each of the hot water pipe 88 and the water supply pipe 76 are provided, and these on-off valves are used for the cooling pipe 92 and the heating pipe 94. You may switch between. In this case, the two on-off valves (not shown) serve as "pipeline switching means".

FIG. 8 is a front view schematically showing the configuration of the heat sterilizer 120 according to the embodiment of the present invention . 9A and 9B are views showing the mounting structure of the fountain nozzle 132 in the heat sterilizer 120, where FIG. 9A is a cross-sectional view and FIG. 9B is a side view. In FIGS. 9A and 9B, the fountain nozzle 132 is shown by a virtual line (dashed-dotted line).

As shown in FIG. 8, the heat sterilizer 120 has a cylindrical main body portion 124 constituting the sterilizer tank 122. The main body portion 124 has a shaft P extending in the horizontal direction, and one end portion (rear end portion) in the axial direction of the main body portion 124 is closed by a closing plate 126. The inner surface 126a of the block plate 126 is provided with a plurality of (four in this embodiment) openings 128. The cooling means 130 of the heat sterilizer 120 has a plurality of (four in this embodiment) fountain nozzles 132 and a plurality of nozzle mounting portions 134 to which these are mounted.

As shown in FIGS. 9A and 9B, the entire mounting surface 136 of each of the plurality of nozzle mounting portions 134 faces the opening 128 and is arranged outside the inner surface 126a of the sterilization tank 122. .. Further, the injection port 132a of the fountain nozzle 132 attached to the nozzle mounting surface 134 is arranged outside the inner surface 126a of the sterilization tank 122. A wall portion 138 for preventing water vapor leakage is formed by a closing plate 126 between the outer peripheral portion of the mounting surface 136 and the inner peripheral portion of the opening 128. The inner surface 138a of the wall portion 138 is formed in a conical shape extending toward the opening 128 to such an extent that the injection angle α of the fountain nozzle 132 can be effectively secured.

According to this embodiment, since the injection port 132a of the fountain nozzle 132 attached to the attachment surface 136 facing the opening 128 is arranged outside the inner surface 126a of the sterilization tank 122, the fountain nozzle 132 is sterilized. It does not protrude inward from the inner surface 126a of the tank 122. Therefore, a larger tray 14 (FIG. 8) can be used, and more objects X to be sterilized can be sterilized at the same time. Further, since the inner surface 138a of the wall portion 138 is formed in a conical shape extending toward the opening 128 to the extent that the injection angle α of the fountain nozzle 132 can be effectively secured, the cooling water injected from the fountain nozzle 132 can be collected. It is possible to prevent the opening 128 from hitting the inner peripheral portion.

X ... Object to be sterilized, α ... Injection angle, 10 ... Heat sterilizer, 12 ... Sterilization tank, 14 ... Tray, 16 ... Cooling means, 18 ... Heating means, 20 ... Compressed air supply means, 22 ... Exhaust means, 24 ... Drainage means, 26 ... cooler, 30 ... control unit, 32a to 32f ... on-off valve, 36 ... three-way valve, 66a ... inner surface, 66 ... peripheral wall part, 68a to 68f ... fountain nozzle, 70a to 70f ... opening, 72a to 72f ... mounting surface, 74a to 74f ... nozzle mounting part, 76 ... water supply pipe, 84 ... wall part, 86 ... steam supply pipe, 88 ... hot water pipe, 92 ... cooling pipe, 94 ... heating pipe, 96 ... Compressed air supply pipe, 98 ... first exhaust pipe, 100 ... second exhaust pipe, 102 ... exhaust control valve, 106 ... inner pipe, 108 ... outer pipe, 110a, 110b ... sealing part, 112 ... first water supply port, 114 ... Second water supply port, 120 ... Heat sterilizer, 138 ... Wall, 138a ... Inner surface.

Claims (7)

A sterilization tank that houses the object to be sterilized and
A tray that is horizontally arranged inside the sterilizer tank and supports the object to be sterilized,
A heating means for heating the object to be sterilized, and
A cooling means for cooling the object to be sterilized is provided.
The heating means has a steam supply pipe for supplying steam inside the sterilization tank.
The cooling means includes a plurality of fountain nozzles for injecting cooling water into the sterilization tank, a plurality of nozzle mounting portions having a mounting surface on which the fountain nozzles are mounted, and water supply for supplying the cooling water to the fountain nozzles. Has a tube and
At least a part of the mounting surface of the at least one nozzle mounting portion is arranged outside the inner surface of the sterilizing tank so as to face the opening provided on the inner surface of the sterilizing tank.
A wall portion for preventing water vapor leakage is provided between the outer peripheral portion of the mounting surface facing the opening and the inner peripheral portion of the opening .
The injection port of the fountain nozzle attached to the attachment surface facing the opening is arranged outside the inner surface of the sterilization tank.
A heat sterilizer in which the inner surface of the wall portion is formed in a conical shape that expands toward the opening to the extent that the injection angle of the fountain nozzle can be effectively secured . The sterilization tank has a cylindrical main body having a shaft extending in the horizontal direction.
The plurality of fountain nozzles are provided in a direction parallel to the tray and in a direction orthogonal to the axis.
The heat sterilizer according to claim 1 , wherein the opening facing the mounting surface is provided at a position separated upward or downward from the shaft. The heating means is
A hot water pipe that is branched from the water supply pipe and is piped, and the water heated inside the sterilization tank is supplied to the water supply pipe as heating water.
It is possible to switch between a cooling pipeline that passes the cooling water through the water supply pipe and supplies it to the fountain nozzle and a heating pipeline that passes the heating water through the hot water pipe and the water supply pipe and supplies it to the fountain nozzle. The heat sterilizing apparatus according to claim 1 or 2 , further comprising a configured pipeline switching means. A compressed air supply means for supplying compressed air to the inside of the sterilization tank is provided.
The heat sterilization apparatus according to any one of claims 1 to 3 , wherein the compressed air supply means has a compressed air supply pipe communicating with the inside of the sterilization tank. Exhaust means for discharging air and water vapor inside the sterilization tank, and
It is equipped with a drainage means for draining the water inside the sterilization tank.
The exhaust means has a first exhaust pipe communicating with the inside of the sterilization tank and a first on-off valve for opening and closing the pipeline of the first exhaust pipe.
The drainage means according to any one of claims 1 to 4 , wherein the drainage means has a drainage pipe communicating with the inside of the sterilization tank and a second on-off valve for opening and closing the pipeline of the drainage pipe. Heat sterilizer. The heat sterilizer according to claim 5 , wherein the exhaust means includes a second exhaust pipe communicating with the inside of the sterilizer tank and an exhaust control valve for adjusting the exhaust flow rate of the second exhaust pipe. A cooler for cooling a mixture of the air, the steam and the water discharged from the exhaust means and the drainage means is provided.
The cooler seals a gap between an inner pipe through which the mixture is passed, an outer pipe provided on the outside of the inner pipe, and an inner surface of the outer pipe and an outer surface of the inner pipe at both ends of the outer pipe. Two sealing portions to be stopped, a first water supply port provided on the pipe wall of the outer pipe, and a second water supply port provided on the pipe wall of the inner pipe between the two sealing portions. Have and
The heat sterilizer according to claim 5 or 6 , wherein the second water supply port is provided on the upstream side of the flow of the mixture flowing through the inner pipe from the first water supply port.

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