Cleanroom installation structure for freezing equipment

Abstract

Eliminate the risk of bacterial growth due to frost and condensation, and ensure a sterile environment within the cleanroom. [Solution] A wall 12 forming a cleanroom 13 with a back space 15 on its rear side has a through-hole holding window 12a into which the freezing device 11 is fitted, and the housing 11b of the freezing device 11 is fitted into the holding window 12a to hold it in place. At this time, the opening and closing door 11a of the freezing device 11 is exposed on the cleanroom 13 side of the wall 12. A refrigerant supply passage 14 for supplying refrigerant to the freezing device 11 is provided in the back space 15 together with the refrigerant container 16 to isolate the area where frost and condensation are likely to occur.

Description

Technical Field

[0001] This invention relates to a structure for installing a freezing device using a refrigerant such as liquid nitrogen in a clean room.

Background Art

[0002] A freezing device using a refrigerant requires a configuration for supplying the refrigerant to the freezing device, that is, a refrigerant container for storing the refrigerant and a refrigerant supply path for sending the refrigerant in the refrigerant container. So far, the refrigerant supply path has been placed in the clean room together with the freezing device.

[0003] However, since an extremely low-temperature liquid is used as the refrigerant, frosting and dew condensation occur on the surface of the pipe constituting the refrigerant supply path.

[0004] The clean room requires a cleanliness level according to the level. Particularly in a biological clean room, not only the air cleanliness but also the microbial cleanliness is required. A clean room that handles living cells and tissues for regenerative medicine and the like needs to be maintained in a sterile state in particular. However, since frosting and dew condensation on the pipe for supplying the refrigerant are inevitable as described above, there is a risk of causing the growth of various bacteria due to moisture. Even if moisture is wiped off every time freezing treatment is performed, it is difficult to completely remove the moisture, so there is a concern about the risk of the growth of various bacteria.

Summary of the Invention

Problems to be Solved by the Invention

[0005] The main problem of this invention is to eliminate the risk of the growth of various bacteria due to frosting and dew condensation.

Means for Solving the Problems

[0006] Therefore, this invention provides the following installation structure for a clean room of a freezing device.

[0007] In other words, the installation structure of the freezing device consists of a wall that constitutes a cleanroom, a clean space, and has a back space on the rear side. A through-hole is formed in the wall into which the freezing device is fitted, and the housing of the freezing device is fitted and held in place by the window. At this time, the opening and closing door of the freezing device is exposed on the side of the wall that faces the clean space. The refrigerant supply passage that supplies refrigerant to the freezing device is provided in the back space on the opposite side of the wall from the clean space.

[0008] In this configuration, the wall isolates the refrigerant supply path, which is prone to frost and condensation, into the back space, thereby eliminating the risk of bacterial growth. [Effects of the Invention]

[0009] According to this invention, a configuration is adopted in which a wall is provided to separate the space containing the refrigerant supply passage from the clean space while holding the freezing device in a through-state. This prevents the growth of bacteria caused by frost and condensation in the refrigerant supply passage from reaching the clean space, thereby maintaining the clean space in a sterile state. [Brief explanation of the drawing]

[0010] [Figure 1] A schematic diagram of the installation structure of a freezing device for a cleanroom. [Modes for carrying out the invention]

[0011] One embodiment for carrying out this invention will be described below with reference to the drawings.

[0012] Figure 1 shows a schematic structure of the installation structure for the freezing device 11 in a cleanroom (hereinafter referred to as the "installation structure"). This installation structure is suitable for installing a freezing device 11 that uses a refrigerant in a cleanroom, especially a biological cleanroom that handles living cells and tissues, and has a configuration that maintains the cleanroom in a sterile state.

[0013] The configuration involves holding the freezing device 11 through the wall 12 to divide the space. Specifically, the opening / closing door 11a of the freezing device 11 is located on the clean space side, i.e., the cleanroom 13 side. On the other hand, the part opposite to the opening / closing door 11a, along with the refrigerant supply passage 14 that supplies refrigerant to the freezing device 11, is located in the back space 15, opposite the cleanroom 13. The wall 12 may be an existing wall that makes up the cleanroom 13, or it may be a wall that is added later. The thickness of the wall 12 is thinner than the depth of the freezing device 11. In this example, one side separated by the wall 12 is the clean space, i.e., the cleanroom 13 which is a sterile controlled area, and the other side is the back space 15, i.e., an uncontrolled area. Figure 1 is a perspective view of the wall 12 in a broken state, showing the cleanroom 13 which is a sterile controlled area and the back space 15 which is an uncontrolled area.

[0014] In the cleanroom 13, the cleanliness of the air is maintained within a predetermined range, and the temperature and humidity are controlled to a certain standard. Clean air is supplied as supply air SA, then discharged as return air RA, and after purification, supplied as supply air SA again. This circulation process is carried out while taking in fresh air, and the cleanroom is always maintained at positive pressure. The method of circulating the air may be unidirectional, non-unidirectional, or other methods.

[0015] The freezing device 11 is held in a wall 12 that constitutes the cleanroom 13 and has a back space 15 on the rear side, or in a wall 12 that divides the installation space for the freezing device 11 into two. The above-mentioned installation space is the space that combines the cleanroom 13 and the back space 15.

[0016] The wall 12 completely partitions the space and is composed of vertical surfaces on both sides. A through-hole holding window 12a is formed in the wall 12 at the height where the freezing device 11 is to be installed, into which the freezing device 11 is fitted. The illustrated example shows an example with one freezing device 11, but it is also possible to have multiple freezing devices 11.

[0017] Here, we will briefly describe the freezing device 11. The freezing device 11 consists of a program freezer that performs freezing according to a freezing program, and as mentioned above, it uses liquid nitrogen as a refrigerant. For this reason, a refrigerant container 16 that stores liquid nitrogen and a refrigerant supply passage 14 that connects the refrigerant container 16 to the freezing device 11 are required. The freezing device 11 has an opening and closing door 11a on the front of the housing 11b for opening and closing the interior, and is a so-called front-door type structure. While the opening and closing door 11a is on the front of the housing 11b, the connection port (not shown) for connecting the refrigerant supply passage 14 and the exhaust port (not shown) for exhausting the interior are formed on the rear side of the housing 11b, opposite to the opening and closing door 11a. The positions of the connection port and exhaust port are such that they are located behind the back surface of the wall 12 when the front part of the housing 11b is fixed to the wall 12. An exhaust passage 17 for exhausting vaporized refrigerant to the outside is connected to the exhaust port, and an opening and closing valve 18 is provided in this exhaust passage 17 and is controlled to open and close by the control unit 19. Furthermore, the freezing device 11 has a cooling function using vaporized refrigerant and a heating function to heat the inside of the storage unit.

[0018] When fitting such a freezing device 11 into the retaining window 12a of the wall 12, the portion of the housing 11b on the side of the opening / closing door 11a is fitted into the retaining window 12a, so that the opening / closing door 11a is exposed on the clean space side of the wall 12, i.e., the cleanroom 13 side. The space between the retaining window 12a of the wall 12 to which the freezing device 11 is attached and the housing 11b is sealed. Depending on the shape of the housing 11b and the structure of the opening / closing door 11a, it is desirable to avoid protruding the freezing device 11 as much as possible into the cleanroom side. This is to prevent the accumulation of foreign matter.

[0019] Although not shown in the diagram, the freezing device 11 is not held solely by the holding window 12a of the wall 12, but is also supported by appropriate support members in the back space 15.

[0020] As the freezing device 11 is held to open towards the cleanroom 13, the refrigerant supply passage 14 that supplies refrigerant to the freezing device 11, along with the refrigerant container 16, is located in the back space 15 on the opposite side of the wall 12 from the clean space (cleanroom 13). The exhaust passage 17 connected to the exhaust port and the control unit 19 that controls the opening and closing of the on / off valve 18 of the exhaust passage 17 are also located in the back space 15.

[0021] The control unit 19 and the on-off valve 18 are configured to ensure a positive pressure state in the cleanroom 13. Specifically, the control unit 19 controls the on-off valve 18 to open only when the freezing device 11 is in cooling operation, and to close the on-off valve 18 when the on-off door 11a is open. In particular, when the control unit 19 receives an open signal from a supply on-off valve (not shown) built into the freezing device 11 that controls the supply of refrigerant, it outputs an open signal to the on-off valve 18 of the exhaust passage 17 to open the valve. When a signal to close the refrigerant supply on-off valve is received, the on-off signal to the on-off valve 18 of the exhaust passage 17 is output because the on-off door 11a may be opened.

[0022] In this way, by controlling the system to open the on-off valve 18 of the exhaust passage 17 only when the freezing device 11 is in cooling operation, exhaust is not released from the exhaust passage 17 when the door 11a is opened, and a positive pressure state is maintained inside the clean room 13.

[0023] Furthermore, it is advisable to adopt a configuration that enhances the reliability of the control by the control unit 19. In other words, the cooling operation of the freezing device 11 should not be performed if the on-off valve 18 of the exhaust passage 14 is not operating. Specifically, a limit switch (not shown) that detects the opening and closing of the on-off valve 18 is provided, and the control unit 19 is configured to allow the start of the cooling operation on the condition that the control unit 19 receives an open signal from the limit switch indicating that the on-off valve 18 is open.

[0024] In the installation structure configured as described above, processes such as cell manufacturing are carried out within the clean room 13. When freezing cells or the like, the opening and closing door 11a of the freezing device 11 is opened and the object is stored in the storage. The supply of the refrigerant is controlled by a predetermined cooling operation based on a program, and the object is frozen as desired. During the cooling operation, the control unit 19 opens the opening and closing valve 18 of the exhaust passage 17 to discharge the vaporized refrigerant to the outside. During the non-cooling operation in which the supply opening and closing valve is closed, the control unit 19 closes the opening and closing valve 18 of the exhaust passage 17.

[0025] After the cooling operation is completed, the opening and closing door 11a is opened to take out the frozen object. At this time, since the opening and closing valve 18 of the exhaust passage 17 is closed, the positive pressure state within the clean room 13 is maintained.

[0026] Due to the cooling operation, frosting and condensation will occur on the surface of the pipes constituting the refrigerant supply passage 14. However, since the refrigerant supply passage 14 is located in the back space 15 rather than in the clean room 13, the risk of the propagation of miscellaneous bacteria within the clean room 13 can be avoided. Therefore, the aseptic state of the clean room 13 can be maintained.

[0027] Moreover, since the freezing device 11 has a cooling function by the vaporized refrigerant and a heating device for heating the inside of the storage, by using the cooling function and the heating function to dry up the inside of the storage after the cooling operation, the risk of the propagation of miscellaneous bacteria in the clean room 13 can be eliminated.

[0028] As described above, this installation structure can significantly reduce the risk of the propagation of miscellaneous bacteria due to frosting and condensation within the clean room 13, and contributes to ensuring the aseptic state.

[0029] The above configuration is another form of implementing this invention. This invention is not limited only to the above-described configuration, and other configurations can also be adopted.

[0030] For example, the refrigerant may be other than liquefied nitrogen, and the clean room 13 may be other than a biological clean room for regenerative medicine or the like.

[0031] Since the back space 15 only needs to isolate the refrigerant supply passage 14, the refrigerant container 16 can be placed outside the back space 15.

[0032] The freezing device 11 may have an opening and closing door on its top surface. [Explanation of Symbols]

[0033] 11...Freezing device 11a...Opening / closing door 11b... Cabinet 12…Wall body 12a... Holding window 13…Cleanroom 14…Refrigerant supply line 15...Back space 16… Refrigerant container 17… Exhaust duct 18…Opening / closing valve 19…Control Unit

Claims

1. Installation structure for a freezing device using a refrigerant, A cleanroom, which is a clean space, is constructed, and a wall body with a back space on the rear side has a through-hole holding window into which the freezing device is fitted. The housing of the freezing device is fitted and held in the holding window, and the opening and closing door of the freezing device is exposed on the side of the wall facing the clean space. A refrigerant supply path for supplying refrigerant to the freezing device is provided in the back space, on the opposite side of the wall from the clean space. Cleanroom installation structure for freezing equipment.

2. Installation structure for a freezing device using a refrigerant, A wall is installed to divide the installation space into two, with one side designated as the clean space and the other as the back space. A through-retaining window is formed in the wall body into which the freezing device is fitted, The housing of the freezing device is fitted and held in the holding window, and the opening and closing door of the freezing device is exposed on the side of the wall facing the clean space. A refrigerant supply path for supplying refrigerant to the freezing device is provided in the back space, on the opposite side of the wall from the clean space. Cleanroom installation structure for freezing equipment.

3. The freezing device has a cooling function using vaporized refrigerant and a heating device for heating the inside of the storage unit. Cleanroom installation structure for a freezing apparatus according to claim 1 or claim 2.

4. An on / off valve is provided in the exhaust passage connected to the exhaust port of the freezing device. A control unit is provided that opens the aforementioned on-off valve only when the freezing device is in cooling operation. Cleanroom installation structure for a freezing apparatus according to claim 1 or claim 2.

5. The freezing device is a front-door type having the opening and closing door on its front. Cleanroom installation structure for a freezing apparatus according to claim 1 or claim 2.

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