JP2003214675A - Internal negative pressure clean working table - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an internal negative pressure clean working table preventing infection to workers, leakage of contaminated aerosol to the outside, and inflow of contaminated aerosol from the outside during an experiment or observation using a microscope. <P>SOLUTION: An internal negative pressure clean table 1 has: a semi-closed working room 3, except a front opening 34 for work, of which upper side is opened and closed by a shutter 35, formed at the top of a working table 2; a means to suck and sterilize contaminated air generated in the working room 3; and a means (7, 8) to supply sterilized air to a working room. The shutter 35 at the front of the working room has a small opening 36 through which an eyepiece unit 52 of a microscope 51 goes outside of the working room. The rim of the small opening 36 has an outer-and-inner two-layered structure, and a means (14) to delivery sterilized air by pressure to a center 15 between the inner and the outer layers is provided, and a gap between the rim and the eyepiece unit 52 is surrounded by positive pressure. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an internal negative pressure type cleaning workbench used for experiments and work involving chemicals harmful to pathogens, humans and the environment.

[0002]

2. Description of the Related Art Cleaning benches are classified into an internal positive pressure type and an internal negative pressure type. The former is called a clean bench and is used to obtain a dust-free and sterile environment. The latter is represented by a safety cabinet, which is used for experiments and work dealing with pathogenic bacteria and chemicals harmful to humans and the environment, and its main purpose is to protect workers and the environment from these dangerous substances.

Such an internal negative pressure type cleaning workbench often uses a microscope in experiments and observations of pathogenic bacteria, etc. Conventionally, when a microscope is used in an internal negative pressure type cleaning workbench, the microscope shown in FIG. As shown in the figure, the worker needs to put his head inside the working chamber to perform the work, and there is a risk that the sample will be infected. A vertical airflow is generally generated in the work chamber of the internal negative pressure type cleaning workbench, but in the work using a microscope, the vertical airflow is blocked by the operator's head or upper body, which makes it easier to inhale contaminated aerosols. Since the opening of the shutter becomes large, the possibility of inflow of contaminated aerosol from the outside into the working chamber and leakage of contaminated aerosol from the working chamber to the outside also increases.

[0004]

SUMMARY OF THE INVENTION In view of the above-mentioned problems of the prior art, the present invention provides infection to workers and leakage of polluted aerosols to the outside and contamination from the outside during experiments and observations using a microscope. The purpose of the present invention is to provide an internal negative pressure type cleaning workbench capable of preventing the inflow of aerosol.

[0005]

In order to achieve the above object, the present invention has a semi-closed working chamber formed on the upper side of a work table except for a front working opening, and at least above the front working opening. One half is openable and closable by a shutter, and is equipped with a means for sucking and collecting the contaminated air generated in the working chamber from one side to aseptically clean it, and a means for supplying clean air from the other side into the working chamber. In the pressure type cleaning workbench,
The shutter on the front of the work room was provided with a small opening for penetrating the eyepiece part of the microscope installed in the work room and exposing it to the outside of the work room. A peripheral portion of the small opening of the work chamber front shutter portion has a two-layer inner and outer layer structure, and means for pumping clean air is provided in the middle portion of the inner and outer layers, and a positive pressure is applied to a gap between the peripheral portion and the microscope eyepiece lens portion. It is preferable to have a structure surrounded by parts.

[0006]

1 to 3 show an embodiment of an internal negative pressure type cleaning work table according to the present invention. In the figure, the internal negative pressure type cleaning workbench 1 (safety cabinet) is
A cabinet main body 5 including a workbench 2, a work chamber 3 formed above the workbench 2, and a main body case 4 is supported on a leg frame 6.

In the work chamber 3, both side surfaces and the ceiling surface of the work chamber frame 31 are shielded by side plates 32, 32 and a top plate 33 made of tempered glass, and a shutter 35 made of tempered glass is provided on an upper front portion inclined forward. While it can be opened and closed, the lower part of the front surface is a working opening 34. The shutter 35 is a flip-up type whose top end is attached to the work chamber frame 31 by a hinge or the like, but it may be a slide type that moves up and down along the inclined portion of the work chamber frame 31. Further, a front panel may be provided in the work opening 34 to partially open the opening range, or a slide cover may be additionally provided in the partial opening so as to be opened and closed.

The body case 4 is provided with an air supply filter 7 made of a HEPA filter in the center of a partition wall 41 constituting the back surface of the work chamber 3, and an air flow made of a perforated plate (punch metal) is provided in front of the air supply filter 7. The diffusion member is provided to configure the clean air blowing unit 42. On the other hand, body case 4
The inside of is partitioned by a partition wall 43 into a positive pressure portion 44 and a negative pressure portion 45, and a turbo fan 8 is provided in the positive pressure portion 44 as a blower. Further, an exhaust filter 9 is provided above the positive pressure portion 44, and an exhaust port 10 is formed.

The workbench 2 is provided with suction ports 21 and 22 along its front and rear edges, and the lower part of the workbench 2 is hollow to form a negative pressure portion 23. The negative pressure portion 23 communicates with the negative pressure portion 45 of the main body case 4, and the suction port 21,
An air flow path is formed from 22 to the negative pressure portions 23 and 45 and the positive pressure portion 44 to the air supply filter 7 and the clean air blowing portion 42.

Then, the air in the negative pressure portions 23 and 45 is pressure-fed to the positive pressure portion 44 by the operation of the turbofan 8, is cleaned by the air supply filter 7, and is horizontally fed into the working chamber 3 from the clean air blowing portion 42. The airflow that is blown out to and is blown horizontally is guided downward by the shutter 35 that forms a forward inclined surface to form a vertical airflow on the workbench 2. The air reaching the workbench 2 is sucked and collected from the suction ports 21 and 22 in the front and rear of the workbench 2, cleaned through the negative pressure part 45, the positive pressure part 44, and the air supply filter 7 and circulated in the work chamber 3. However, a part of the air is cleaned by the exhaust filter 9 and discharged to the outside through the exhaust port 10.

As a result, the work table 2 is constantly kept at a low negative pressure, and external air corresponding to the amount of air discharged from the exhaust port 10 flows in through the work opening 34. From the suction port 21 at the front end of the workbench 2 directly to the negative pressure portion 23
While being sucked and collected inside, the worktable 2 is prevented from being contaminated by the inflowing outside air, while the contaminated aerosol generated on the worktable 2 is prevented from leaking out by the inflowing air flow.

In the internal negative pressure type cleaning work table 1 having the basic structure as described above, the eyepiece portion 52 of the microscope 51 installed in the work chamber 2 is penetrated through the shutter 35 in the front of the work chamber 2 substantially in the center thereof. A small opening 36 for opening to the outside of the work chamber 2 is opened. As shown in FIG. 3 (b), the small opening portion 36 has a shape in which two circular holes are connected to each other so as to penetrate the binocular eyepiece lens portion 52, or has a long hole, and is provided on the outer surface side of the small opening portion 36. Is provided with a cover 11.

The cover 11 is made of a transparent material such as plastic and has a peripheral wall portion 11a surrounding the small opening portion 36 over a range slightly larger than the small opening portion 36, an installation surface,
In other words, the rubber cover 12 is formed by the flat surface portion 11b parallel to the surface of the shutter 35, and the flat surface portion 11b is provided with a rubber cover 12 having a small opening portion 12a having the same shape as or slightly smaller than the small opening portion 36 at the center. Then, the pipe connecting portion 1 penetrating the air outlet 13a is formed on the peripheral wall portion 11a on one side of the cover 11.
3 is formed, and an air feed pipe 14 for feeding clean air under pressure is connected to the pipe connecting portion 13. Cover 11 has shutter 3
5 may be permanently fixed to the surface or may be detachably fixed by an appropriate means.

By the cover 11 and the shutter 35, the small opening portion 36 (12a) has a two-layer structure of the inner and outer layers, and the clean air is pressure-fed to the intermediate portion 15 of the inner and outer layers through the air feed pipe 14. The inner / outer layer intermediate portion 15 serves as a positive pressure portion, and the gap between the peripheral portion of the small opening portion 36 (12a) and the eyepiece lens portion 52 is surrounded by the positive pressure portion (15). Therefore, the flow of the inside and outside air through the gap is blocked, and the leakage of the contaminated aerosol and the inflow of the outside contaminated aerosol are prevented. Then, the operator does not need to put his head into the working chamber 3 when using the microscope 51, and the operator's head and the sample are separated by the shutter 35, and the sample can be prevented from infecting the operator.

The forwardly tilted shutter 35 allows the operator to use the microscope 51 in a natural posture, and the eyepiece 52 of the tilted microscope 51 penetrates the small opening 36 (12a) substantially vertically. Therefore, there is an advantage that the gap around the small opening portion 36 can be reduced and the shutter 35 can be opened and closed with the microscope 51 installed. Further, by making the small opening 12a of the outer rubber cover 12 slightly smaller than the small opening 36 of the inner shutter 35 as in the illustrated example, the blowing of clean air to the operator side is reduced, and the work is performed. There is also an advantage that it is easy.

As a means for feeding clean air into the cover 11 through the air feed pipe 14, it is advantageous to use a portable small clean air supply unit 16 as shown in FIG. 4, for example. The small clean air supply unit 16 is provided with a HEPA filter 62 and a small blower 63 in the case 61, and the air sucked into the case 61 through the pre-filter 64 is sterilized and cleaned by the HEPA filter 62 to make the air supply pipe 14 And 65 is a handle. Since this small-sized clean air supply unit 16 is independent of the internal negative pressure type cleaning work table 1, the clean air can be stably supplied into the cover 11 without being affected by the air flow of the internal negative pressure type cleaning work table 1 itself.

Instead of using the small-sized clean air supply unit 16, the air supply pipe of the existing equipment is replaced by a regulator,
The clean air is supplied to the inside of the cover 11 through the HEPA filter, or the small clean air supply unit 16
The structure corresponding to the above may be incorporated in the internal negative pressure type cleaning work table 1 itself. Further, a part of the circulating air flow (positive pressure portion 44) of the internal negative pressure type cleaning work table 1 itself may be introduced into the cover 11.

In the above embodiment, the case where the cover 11 is provided on the outer surface of the shutter 35 has been described.
Can be provided inside the shutter 35. In particular,
When a part of the circulating air flow of the internal negative pressure type cleaning workbench 1 itself is introduced into the cover 11, the cover 11 is closed by the shutter 35.
It is advantageous to provide it inside the. Further, instead of supplying clean air into the cover 11 to make the inside of the cover 11 a positive pressure portion, a duct connected to the suction means is connected to the cover 11 to make the inside of the cover 11 a negative pressure portion, and from the small opening portion. The inflowing external pollutant aerosol and the pollutant aerosol generated in the working chamber 3 may be sucked and collected.

Further, when the sample to be handled, the risk of pathogenic bacteria, or only the cleanliness of the working chamber 3 is required, the clean air pressure feeding means and the cover 11 are not used, and the working chamber 2 is not used. Eyepiece section 5 of microscope 51 installed in
It is also possible to carry out the work by putting 2 out of the work chamber 2 through the small opening 36. Even in that case, the gap between the peripheral portion of the small opening portion 36 and the eyepiece lens portion 52 is small, and the vicinity of the inside of the small opening portion 36 is under the influence of the air current flowing along the shutter 35. As a matter of course, it has a function of suppressing the contaminated aerosol generated from the sample, and is safer than the conventional technique in which the worker puts his head in the working chamber to perform the work.

In the above embodiment, the case where the thin turbofan 7 is used as the air blower and is arranged on the back surface of the working chamber 3 is shown. However, the air blower may be of a type other than the turbofan, such as a sirocco fan. good. Further, the blowing means can be arranged below the work table. Further, the air supply filter may be arranged on the side of the blower means suction side below the workbench to form a negative pressure type, in which case the exhaust filter can be omitted.

[0021]

As described in detail above, in the internal negative pressure type cleaning workbench of the present invention, a semi-closed work chamber is formed on the upper side of the workbench except the front work opening, and the front work opening is formed. At least the upper half of the can be opened and closed by the shutter,
In addition, in the internal negative pressure type clean workbench equipped with means for sucking and collecting the contaminated air generated in the work chamber from one side and aseptically cleaning it, and means for supplying clean air from the other side into the work chamber, Since the shutter part has a small opening for penetrating the eyepiece part of the microscope installed in the working room to let it out of the working room, it is possible to infect workers during experiments and observations using the microscope, and Leakage of polluted aerosol and inflow of polluted aerosol from the outside can be prevented.

Further, the peripheral portion of the small opening of the front shutter portion of the working chamber has a two-layer structure of inner and outer layers, and means for pumping clean air to the middle portion of the inner and outer layers is provided, and the peripheral portion and the microscope eyepiece portion are provided. Since the gap is surrounded by a positive pressure part, it is possible to more reliably prevent infection of workers, leakage of contaminated aerosol to the outside, and inflow of contaminated aerosol from the outside during experiments and observation using a microscope. .

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing an internal negative pressure type cleaning workbench according to an embodiment of the present invention.

FIG. 2 is a longitudinal sectional view of a main part showing an air flow state in the internal negative pressure type cleaning work table according to the embodiment of the present invention.

FIG. 3A is an enlarged cross-sectional view of an essential part showing the vicinity of a small opening in the internal negative pressure type cleaning workbench of the embodiment of the present invention;
Is a front view of the same portion.

FIG. 4 is a vertical sectional view showing a small clean air supply unit.

FIG. 5 is a vertical cross-sectional view showing a conventional internal negative pressure type cleaning work table.

[Explanation of symbols]

1 Internal negative pressure type cleaning workbench 2 workbench 3 workspace 4 body case 7 Air supply filter 8 Turbo fan (Blower means) 9 exhaust filter 10 exhaust port 11 cover 12 rubber cover 14 Air supply pipe 15 Middle part of inner and outer layers (positive pressure part) 16 Small clean air supply unit 21,22 Suction port 23, 45, negative pressure part 31 Working room frame 32 side plate 33 Top plate 34 Working opening 35 shutter 36 Small opening 41, 43 partition walls 42 Clean air outlet 44 Positive pressure part 51 microscope 52 Eyepiece part

Claims (2)

[Claims] 1. A work chamber in a semi-sealed state is formed on the upper side of a work table except for a front work opening, and at least an upper half portion of the front work opening can be opened and closed by a shutter,
In addition, in the internal negative pressure type clean workbench equipped with means for sucking and collecting the contaminated air generated in the work chamber from one side and aseptically cleaning it, and means for supplying clean air from the other side into the work chamber, An internal negative pressure type clean workbench characterized in that the shutter part has a small opening for penetrating the eyepiece part of the microscope installed in the work room to be exposed to the outside of the work room. 2. A peripheral portion of a small opening portion of a front shutter of a work chamber has a two-layer structure of an inner and outer layers, and means for pumping clean air is provided in an intermediate portion of the inner and outer layers, and the peripheral portion and the microscope eyepiece portion are provided. The internal negative pressure type clean workbench according to claim 1, wherein the gap is surrounded by a positive pressure portion.