safety cabinet

Abstract

It is possible to maintain laminar flow with high wind speed, and to minimize contamination caused by the operation of the device or human manipulation of the device. It is a safety cabinet having an opening on the front side and a front shutter inside the workroom, and supplying clean air into the workroom from above; partition plates are provided on the left and right sides and the rear side above the workroom, and a partition is also provided on the front upper side of the workroom.

Description

Technology Field

[0001] The present invention relates to a safety cabinet used for regenerative medicine, industrial use, development of pharmaceuticals, research on pathogens, etc. Background Technology

[0002] Safety cabinets are used when handling pathogens, such as in the manipulation and observation of cells, research on pathogens like viruses, or the development of pharmaceuticals like vaccines.

[0003] As an example of a safety cabinet, Patent Document 1 discloses a safety cabinet in which a HEPA filter for exhaust is provided at the top of the work chamber, a front shutter that can be opened and closed is provided at the front of the work chamber, a rear grille is provided at the lower rear, and a front grille is provided at the lower front. Then, air is uniformly supplied into the work chamber from the HEPA filter for exhaust, and air is drawn in through the front grille and rear grille of the work table forming the bottom of the work chamber, thereby causing air to descend uniformly from top to bottom and cleaning the work chamber. Prior art literature

[0004] Japanese Patent Publication No. 2019-74237 The problem to be solved

[0005] By using a safety cabinet, contamination caused by the manipulation or observation of cells or the handling of pathogens within the workroom can be prevented, and furthermore, pathogens can be prevented from leaking from within the workroom to the worker.

[0006] In the safety cabinet disclosed in Patent Document 1, the operator sits in front of the safety cabinet and performs work by inserting their arm into the work chamber through the work opening below the front shutter, but the installation and handling of devices such as cell manufacturing machines like bio 3D printers or conveying machines inside the safety cabinet is not considered. In other words, the downflow wind speed of the entire work chamber when devices are installed inside the work chamber is not considered.

[0007] The present invention aims to provide a safety cabinet that prevents contamination of cells or pathogens when a device such as a cell manufacturing machine or a conveying machine, such as a bio 3D printer, is installed inside the safety cabinet.

[0008] In addition, the purpose is to provide a safety cabinet capable of preventing cells, pathogens, etc. from leaking from inside the workroom to the worker. means of solving the problem

[0009] An example of a “safety cabinet” of the present invention for solving the above problem is provided, which comprises a work chamber maintaining a negative pressure state formed inside a front shutter, and a circulation path formed between the lower side of the work chamber, the side side of the work chamber, the rear side of the work chamber, and the outer part of the safety cabinet, and a device mounted in the work chamber, wherein the safety cabinet has a partition plate such that the lower part of the work chamber has a wider horizontal cross-sectional area than the upper part of the work chamber.

[0010] In addition, another example of the “safety cabinet” of the present invention is a safety cabinet having an opening on the front side of a workroom and a front shutter, and supplying clean air from above into the workroom, and a work table on which a device is installed, having an exhaust slit along the outer periphery of the device on the surface of the work table on which the device is installed, which is connected to an exhaust circulation path below the work table. Effects of the invention

[0011] According to the present invention, by providing partition plates on the left and right sides and the rear side of the upper part of the workroom, a high wind speed, for example, equivalent to 0.45 m / s, can be maintained to ensure laminar flow within the workroom.

[0012] In addition, by providing a partition at the upper front side of the workroom, a high wind speed, for example, equivalent to 0.45 m / s, can be maintained to ensure laminar flow within the workroom.

[0013] In addition, it is possible to ensure cleanliness without allowing oscillations caused by the operation of the device to leak to the outside, and also provide a safety cabinet that prevents leakage from inside the workroom to the worker.

[0014] In addition, a strong air barrier can be formed by two layers of clean air: clean air on the inner side of the front shutter workroom and clean air on the inner side of the partition on the front upper side of the workroom, thereby suppressing contamination caused by the operation of the device or human work.

[0015] Tasks, configurations, and effects other than those mentioned above will be revealed by the description of the following embodiments. Brief explanation of the drawing

[0016] FIG. 1a is a front view of the safety cabinet of Example 1. FIG. 1b is a cross-sectional view of the safety cabinet of Example 1. FIG. 2a is a perspective view of the safety cabinet of Example 2. FIG. 2b is a cross-sectional view of the safety cabinet of Example 2. Fig. 3a is a front view of the safety cabinet. Fig. 3b is a cross-sectional view of a safety cabinet. Specific details for implementing the invention

[0017] Before describing the embodiments of the present invention, the airflow of the safety cabinet is described.

[0018] FIG. 3a shows a schematic front view of a safety cabinet, and FIG. 3b shows a schematic cross-sectional view of the safety cabinet viewed from the left side of the AA' section of FIG. 3a.

[0019] Safety cabinets include various types of cabinets, such as those for regenerative medicine or industrial use. In the following description, safety cabinets used for the development of pharmaceuticals or research on pathogens will be specifically described.

[0020] A workroom (102) is positioned inside a safety cabinet (100), with the front surface configured as a front shutter (103). The workroom (102) maintains a negative pressure state formed on the inner side of the front shutter. A work opening (104) is formed below the front shutter (103), and a worker inserts their arm into the workroom (102) through the work opening (104) and performs work while looking into the workroom (102) through the front shutter (103).

[0021] The lower surface of the workroom (102) is formed by a work table (101), and a front slit (104a) is positioned on the front side of the work table (101) near the front shutter (103). When the safety cabinet fan (106) is operated, the pressure chamber (109) is pressurized. A HEPA filter (111) for ejection is connected to the pressure chamber (109), and dust inside the pressure chamber (109) is filtered by the HEPA filter (111) for ejection, and purified air is ejected, rectified by the ejection rectification plate (107), and then supplied as an ejection airflow (113) into the workroom (102).

[0022] An exhaust HEPA filter (110) is also connected to the upper part of the pressure chamber (109). The air pressurized in the pressure chamber (109) is filtered by the exhaust HEPA filter (110) and is exhausted from the safety cabinet (100) as exhaust air (114) through the safety cabinet exhaust port (108).

[0023] An amount of air (inflow airflow (112)) equal to the air exhausted from the safety cabinet (100) (exhaust air (114)) enters the safety cabinet (100) from the working opening (104) below the front shutter (103). This air is the inflow airflow (112) generated at the working opening (104) below the front shutter (103). The inflow airflow (112) is sucked into the front slit (104a) together with a portion of the ejected airflow (113) in the workroom (102). This air passes under the work table (101). The inflow airflow (112) is sucked in along with a portion of the outflow airflow (113) from the rear slit (105a) formed on the opposite side of the front shutter (103) of the workroom (102), and is sucked into the safety cabinet fan (106) through the circulation path (105). The circulation path (105) is formed on the lower side of the workroom (102), the side side of the workroom, the rear side of the workroom, and the outer part of the safety cabinet. That is, the inflow airflow (112) sucked in from the work opening (104) is circulated by the path consisting of the lower part of the work table (101) (the lower side of the workroom (102)), the side and rear of the workroom (102), and the main body part of the safety cabinet (100). The inflow airflow (112) passing through the circulation path (105) is sucked into the safety cabinet fan (106) and discharged from the safety cabinet (100) as exhaust air (114).

[0024] Since dust and aerosols containing pathogens are handled within the workroom (102), dust and aerosols containing pathogens are also present within the circulation path (105) and pressure chamber (109). These dust and aerosols are removed by the HEPA filter (111) for ejection when air is supplied to the workroom (102), and by the HEPA filter (110) for exhaust when air is exhausted from the safety cabinet (100).

[0025] The worker sits in front of the safety cabinet (100), inserts their arm into the workroom (102) through the work opening (104), and performs work while looking into the workroom (102) through the front shutter (103).

[0026] In the case of such safety cabinets, Japanese Industrial Standard JIS K 3800-2009 states that the ejection wind speed test for verifying airflow balance shall be conducted at the specified point after removing removable parts inside the cabinet.

[0027] In open systems such as safety cabinets, even if cell manufacturing machines such as bio 3D printers or conveying machines are installed in the workroom of the safety cabinet, it is required to set the downflow air velocity in the workroom to a constant value, for example, 0.45 m / s ± 20% (0.36 to 0.54 m / s).

[0028] The conventional safety cabinet fan (106) alone is insufficient to meet this requirement. Therefore, the addition of an exhaust fan or a large-capacity circulation fan becomes necessary, which leads to the enlargement of the safety cabinet. In some cases, the enlarged safety cabinet may be impossible to install in the existing installation space or to bring into the installation space.

[0029] Furthermore, it is undesirable as it increases power consumption and noise. Increased power consumption also does not meet the demands of the post-oxygenation era.

[0030] According to the safety cabinet of the present embodiment, when a device such as a cell manufacturing machine or a conveying machine, such as a bio 3D printer, is installed inside the safety cabinet, a high-velocity down-flow airflow capable of guaranteeing laminar flow within the workroom can be maintained.

[0031] In addition, according to the safety cabinet of the present embodiment, the cleanliness of the surrounding area of ​​the installation location of the device installed in the workroom (102) can be secured.

[0032] In addition, the safety cabinet of the present embodiment can prevent leakage from the workroom to the worker.

[0033] Hereinafter, embodiments of the present invention will be described using the drawings. In addition, in each drawing for describing the embodiments, the same components are given the same names and reference numerals, and the description of such repetition is omitted.

[0034] Example 1

[0035] FIGS. 1a and 1b illustrate an example of the structure of a safety cabinet (100) corresponding to a Class II cabinet for biohazard countermeasures according to Example 1. FIG. 1a is a front view thereof. FIG. 1b is a cross-sectional view of the AA' section of the safety cabinet (100) shown in FIG. 1a, viewed from the left direction.

[0036] The safety cabinet according to the present embodiment has an opening on the front side of the workroom and a front shutter, supplies clean air into the workroom from above, provides partition plates on the left and right sides and the rear side of the upper part of the workroom, and also provides a partition on the upper front side of the workroom.

[0037] FIG. 1a illustrates a safety cabinet (100) of Example 1 of the present invention. The workroom (102) maintains an illumination level suitable for work by means of lighting, etc. Additionally, a sterilization lamp is generally equipped on the upper rear surface of the workroom (102). This sterilization lamp is used as an auxiliary measure for sterilizing the workroom (102) before and after work, in combination with decontamination by wiping with 70% alcohol, etc.

[0038] As for the performance of the safety cabinet (100), it is extremely important that the worker is not infected by bacteria or viruses handled inside, and this function is achieved by isolating the air inside the workroom (102) and outside the safety cabinet (100) by means of a front shutter (103).

[0039] The safety cabinet (100) of Example 1 is equipped with side partition plates (130) and rear partition plates (131) on the left and right sides of the upper part of the workroom.

[0040] The side partition plate (130) and the rear partition plate (131) are attached in a manner that suppresses the opening of the discharge rectifier plate (107) and restricts the discharge portion of the discharge airflow (113). By doing so, the wind speed of the discharge airflow (113) is increased without a significant structural change while remaining as a conventional safety cabinet fan (106), and it is possible to maintain a wind speed of 0.45 m / s ± 20% (0.36 to 0.54 m / s) which is the standard for laminar flow.

[0041] The side partition plate (130) and the rear partition plate (131) are inclined outwardly about 150 mm below the discharge rectifier plate (107). This inclination is an angle (120) that meets the side of the workroom inside the safety cabinet (100) and the side partition plate (130) and the rear partition plate (131), and is about 30 to 45 degrees. Due to the inclination of the side partition plate (130) and the rear partition plate (131), the upward curling of the discharge airflow (113) is minimized, and the stagnation of the discharge airflow (113) is suppressed. Near the work table (101), the structure is designed so that neither the side partition plate (130) nor the rear partition plate (131) is present, thereby securing the installation space and work space of the device.

[0042] The device installed on the workbench (101) can be conceived in various shapes, and the side partition plate (130) and the rear partition plate (131) can be slid vertically to adjust the upper space of the workroom (102), and can be shaped to fit the device being installed.

[0043] In that case, the side partition plate (130) and the rear partition plate (131) are configured to slide up and down by about 100 mm to 200 mm. Depending on the machine installed in the workroom (102), but considering the greater compatibility with the machine, it is preferable to configure them to only move up and down by 50 mm to 300 mm. By sliding the side partition plate (130) and the rear partition plate (131) up and down, a down-flow air velocity can be maintained while maintaining laminar flow to the parts of the device or work areas where cleanliness is required, and cleanliness can be secured.

[0044] Although the side partition plate (130) and the back partition plate (131) are described as being inclined to slide up and down, a mechanism for adjusting the inclination of the side partition plate (130) and the back partition plate (131) may also be provided. Additionally, although the side partition plate (130) and the back partition plate (131) were described as basically straight partition plates, they may be configured with a convex curve inside the workroom (102).

[0045] That is, by taking into account the horizontal cross-sectional area of ​​the workroom (102), the area near the upper part of the workroom (102) (ejection rectification plate (107)) is the smallest due to partition plates such as the side partition plate (130) and the rear partition plate (131), and is configured to gradually widen up to the point where the side partition plate (130) and the rear partition plate (131) come into contact with the side of the workroom (102).

[0046] In addition, by providing an airflow partition plate (132) on the upper front side of the workroom, high-speed clean air can be secured in the device installation area where laminar flow and high cleanliness are required.

[0047] In the safety cabinet (100) of Example 1, the airflow partition plate (132) is installed at a predetermined distance, for example, from 30 mm to 100 mm in the depth direction of the work room (102) from the front shutter (103). The airflow partition plate (132) is a partition plate with a length of 300 mm in the downward direction from the ejection rectifier plate (107) and facing downward into the work room (102), and partitions the airflow from the ejection rectifier plate (107) into the ejection airflow (113) and the airflow behind the front shutter (133). The front shutter is installed such that the bottom of the front shutter (103) is located 200 mm upward from the work table (101). The bottom of the airflow partition plate (132) is located 250 mm above the bottom of the front shutter (103). In the safety cabinet of this embodiment, the distance from the work table (101) to the bottom of the front shutter (103) (distance A), the distance from the bottom of the front shutter (103) to the bottom of the airflow partition plate (132) (distance B), and the vertical length of the airflow partition plate (distance C) are 200 mm, 250 mm, and 300 mm, respectively. If distances A, B, and C are configured in a ratio of 4:5:6, the air barrier effect of the airflow behind the airflow partition plate (132) with increased wind speed is promoted, and contamination caused by the operation of the device's return section or manual work by a person can be suppressed. The ratio of distances A, B, and C can be adjusted within a range of ±10 to 20% depending on the size of the machine installed in the work room (102).

[0048] Additionally, by means of the airflow partition plate (132), the airflow behind the front shutter (133) on the side of the workroom (102) of the front shutter (103) is maintained at a wind speed (0.30 to 0.40 m / s) equivalent to that of a conventional safety cabinet without increasing the airflow behind the front shutter. By doing so, an air barrier can be maintained by a stable inflow airflow (112), and airflow balance performance, which is a stable airflow sealing performance equivalent to that of a safety cabinet, can be maintained. If the wind speed of the airflow behind the front shutter (133) is too strong, the downflow airflow with a strong wind speed comes into direct contact with the worker's arm, and thus contamination cannot be suppressed. By providing the airflow partition plate (132), the wind speed of the airflow behind the front shutter (133) can be set to 0.30 to 0.40 m / s, and contamination can be effectively suppressed.

[0049] In addition, by using an inflow airflow (112) with a high wind speed of about 0.60 m / s and a high downflow airflow of 0.45 m / s in the workroom (102) partitioned by a side partition plate (130) and a back partition plate (131), the airflow behind the front shutter between them is suppressed to a wind speed lower than the surroundings, which is 0.30 to 0.40 m / s. As the inflow airflow (112) and the outflow airflow (113) come into contact with the workroom (102) side of the airflow partition plate (132), the air barrier effect of the airflow behind the airflow partition plate (132), which has a higher wind speed due to the Coanda effect, is promoted, and contamination caused by the operation of the device's conveying part or manual work by a person can be suppressed.

[0050] Example 2

[0051] FIGS. 2A and 2B illustrate a safety cabinet of Example 2. FIG. 2A is a perspective view of the safety cabinet of Example 2. FIG. 2B is a cross-sectional view of the AA' section of the safety cabinet (100) illustrated in FIG. 2A, viewed from above.

[0052] In the workbench (101) of the safety cabinet of Example 2, a plurality of workbench exhaust slits (135) are provided that penetrate the exhaust circulation path (134) (see FIG. 1b) in accordance with the outer circumference of the device being installed.

[0053] Work table exhaust slits (135) are provided in multiple locations, such as the upper left and right sides and the rear side of the work room of the safety cabinet (100), near the work opening (104), that is, the periphery of the device installed on the work table (101) (periphery of the work table (101)).

[0054] Dust generated by operating the device's return section or by a person operating the device through the workbench exhaust slit (135) is exhausted into the exhaust circulation path (134) without remaining in the workroom (102) and is cleaned by the exhaust HEPA filter (110) (see FIG. 3b) or the discharge HEPA filter (111) (see FIG. 3b). Explanation of the symbols

[0055] 100: Safety Cabinet 101: Workbench 102: Studio 103: Front shutter 104: Work opening 105: Circulating Euro 106: Safety cabinet fan 107: Ejection rectifier 108: Exhaust pipe 109: Pressure chamber 110: Exhaust HEPA filter 111: HEPA filter for exhaust 112: Inflow airflow 113: Eruptive airflow 114: Exhaust air 130: Side partition 131: Back partition panel 132: Airflow partition 133: Airflow behind the front shutter 134: Exhaust circulation path 135: Workbench Exhaust Slit

Claims

Claim 1 A safety cabinet having a workroom formed on the inner side of a front shutter, a circulation path formed on the lower side of the workroom, a side side of the workroom, a rear side of the workroom, and an outer part of the safety cabinet, wherein a device is mounted in the workroom, the safety cabinet is characterized by having a discharge rectifier plate that supplies a rectified discharge airflow to the workroom, and a partition plate such that the lower part of the workroom has a wider horizontal cross-sectional area than the upper part of the workroom, wherein the partition plate has a side partition plate inclined toward the side of the workroom at a predetermined distance downward from the discharge rectifier plate, and a rear partition plate inclined toward the rear of the workroom at a predetermined distance downward from the discharge rectifier plate. Claim 2 A safety cabinet according to claim 1, characterized by having an airflow partition plate facing downward into the workroom from the discharge rectifier plate at a predetermined distance from the front shutter. Claim 3 A safety cabinet according to paragraph 2, characterized in that the side partition plate and the rear partition plate are configured to slide up and down within the workroom. Claim 4 A safety cabinet according to paragraph 2, characterized in that the side partition plate is inclined to be in contact with the side of the workroom at an angle of 30 to 45 degrees, and the rear partition plate is inclined to be in contact with the side of the workroom at an angle of 30 to 45 degrees. Claim 5 A safety cabinet according to paragraph 2, characterized in that the lower end of the airflow partition plate is above the lower end of the front shutter. Claim 6 A safety cabinet according to claim 5, characterized in that the airflow partition plate suppresses the airflow behind the front shutter between the airflow partition plate and the front shutter more than the airflow in the device installation area within the workroom. Claim 7 A safety cabinet according to claim 1, characterized in that, on a workbench in which the lower surface of the workroom is formed and the device is installed, an exhaust slit is provided along the periphery of the device. Claim 8 delete

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