JP2007260499A - Cabinet having clean circumstance retaining mechanism - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cabinet which has a clean circumstance retaining mechanism and causes little variation of the wind velocity in the working space. <P>SOLUTION: The safety cabinet 1 has a filter 26 and two rectification members 51 and 52 in the downstream of the filter 26, and the rectification members 51 and 52 are made of a punching metal and arranged so that the openings 55 and 56 are not superimposed mutually. The rectification members 51 and 52 are formed by bending a sheet of a punching metal and have a bent part 60, and an opening 61 is formed in the bent part 60. Air passing through the filter 26 is rectified by the rectification member 51, stays temporarily in a space 50 and is rectified again by the rectification member 52 so as to supply air with a uniform wind velocity into the working space 7. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a cabinet with a clean environment maintaining function, such as a safety cabinet and a clean bench.

A cabinet with a clean environment maintaining function is known as an apparatus used for injection and other dispensing operations and gene recombination experiments (Patent Documents 1 and 2).
A cabinet with a clean environment maintaining function (hereinafter sometimes simply referred to as “cabinet”) is generally called a safety cabinet or a clean bench, and a work table and a work space are provided inside the housing. Is provided. The cabinet is also equipped with a blower for circulating the air in the work space and a filter for purifying the air. The air in the work space is constantly ventilated or circulated by the above-described blower, and the work space is always maintained in a sterile state.

The device called a safety cabinet is used for preparations of highly toxic and allergic drugs, for example, mixed preparations of injections such as anti-cancer drugs with strong cytotoxicity, and experiments dealing with pathogenic bacteria. The working space is maintained at a negative pressure so that poisonous substances and toxic gases do not leak outside.
On the other hand, a device called a clean bench is used when preparing a preparation of a drug having relatively low toxicity, for example, IVH (Central Intravenous Nutrition) or the like, and the drug itself is used for bacteria or the like. The working space is maintained at a positive pressure to prevent contamination.

The basic configuration of both is the same, and both have a front surface made of glass, acrylic, or the like, so that the work space can be seen from the outside. An open / close door is provided on the front of the cabinet.
JP 2005-235882 A JP 2005-48971 A

In a safety cabinet or clean bench, it is desirable that the clean air that has passed through the filter is supplied into the working space without stagnation.
Therefore, it is desirable that the wind speed in each part of the work space has a small variation. That is, when clean air is supplied into the work space, if the wind speed varies, the work space may not be maintained at a predetermined pressure. Specifically, if the wind speed fluctuates, it will not be possible to maintain negative pressure normally in the case of a safety cabinet and positive pressure in the case of a clean bench, and there is a risk of contaminating workers and chemicals during work. There is a concern that the flow of air to be generated may occur. Furthermore, there is a concern that the cleanliness in the work space cannot be maintained at a predetermined value.

On the other hand, in a safety cabinet or a clean bench, the clogging of the filter gradually proceeds as the usage time elapses. The clogging of the filter causes a variation in the distribution of the wind speed when passing through the filter, and as a result, the variation in the wind speed in each part of the work space increases.
SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to solve the above-mentioned problems of the prior art, and to provide a cabinet with a clean environment maintaining function in which variation in wind speed in a work space is small.

  The invention described in claim 1 for solving the above-described problem includes a work space having an opening into which a hand can be inserted, a blower, and a filter, and supplies air that has passed through the filter to the work space. In the cabinet with a clean environment maintaining function, the cabinet with the clean environment maintaining function is characterized by having at least two rectifying members in the air flow path from the filter to the work space.

In the cabinet with a clean environment maintaining function of the present invention, at least two rectifying members are provided in the air flow path from the filter to the work space. Therefore, the wind speed of the air passing through the rectifying member is made uniform, and the wind speed in the work space is smoothed.
In the cabinet with a clean environment maintaining function of the present invention, air passes through two or more rectifying members after passing through the filter, and is supplied to the work space. Therefore, the wind speed of the air passing through the filter varies due to clogging of the filter or the like. However, the air velocity of air can be made uniform by the two or more rectifying members that follow. As a result, the variation in wind speed at each part in the work space is highly suppressed.

  The invention according to claim 2 is the cabinet with a clean environment maintaining function according to claim 1, wherein the at least two rectifying members are plate bodies having a large number of openings.

In the cabinet with a clean environment maintaining function of the present invention, a plate having a large number of openings is used as the rectifying member. As a specific rectifying member, a punching metal or the like can be used.
In the cabinet with a clean environment maintaining function of the present invention, an excellent rectifying effect can be exhibited even though the rectifying member has a simple structure.

  The invention according to claim 3 is the cabinet with a clean environment maintaining function according to claim 2, wherein the at least two rectifying members are installed in a state where the positions of the openings are shifted.

  In the cabinet with a clean environment maintaining function of the present invention, the rectifying member is installed in a state where the position of the opening is shifted. That is, in the cabinet with a clean environment maintaining function of the present invention, the opening of the upstream rectifying member and the opening of the downstream rectifying member are not arranged so as to communicate linearly, but pass through the upstream rectifying member. The air once hits a portion other than the opening of the downstream rectifying member, so that the air is suitably retained in a gap portion provided between the two rectifying members. Subsequently, the direction of the air passing through the downstream rectifying member changes when passing, and the wind speed of the air after passing is made more uniform. As a result, the variation in wind speed at each part in the work space can be suppressed to a higher degree.

  The invention according to claim 4 is the cabinet with a clean environment maintaining function according to any one of claims 1 to 3, wherein a space is provided between at least two rectifying members.

  In the cabinet with a clean environment maintaining function of the present invention, a gap is provided between the two rectifying members. The air that has passed through the filter is first rectified to some extent by the upstream rectifying member, and temporarily stays in the gap with the downstream rectifying member. Thereafter, the air is rectified again when passing through the rectifying member on the downstream side, and air with a more uniform wind speed is supplied to the work space. As a result, the variation in wind speed at each part in the work space can be suppressed to a higher degree.

  According to a fifth aspect of the present invention, the at least two rectifying members are different in at least one of the shape or size of the opening, and the clean environment according to any one of the first to fourth aspects It is a cabinet with a maintenance function.

  In the cabinet with a clean environment maintaining function of the present invention, the size and the like of the opening are different between the upstream rectifying member and the downstream rectifying member, thereby controlling the amount of air retained in the gap portion of the rectifying member. it can. As a result, in the cabinet with a clean environment maintaining function of the present invention, air can be sent to the work space at a uniform wind speed without being greatly affected by the amount of air sent from the blower, and each part in the work space The variation in wind speed in the is suppressed to a higher degree.

  In the invention according to claim 6, each of the two rectifying members has a planar portion having an opening, the upper portions of the surfaces are overlapped substantially in parallel, and there is a gap between the two, The cabinet with a clean environment maintaining function according to any one of claims 1 to 5, wherein the cabinet communicates with a work space via a portion other than the opening.

  In the cabinet with a clean environment maintaining function of the present invention, each of the two rectifying members has a planar portion having an opening, the upper portions of the surfaces are overlapped substantially in parallel, and there is a gap between the two. Further, the gap communicates with the work space via a portion other than the opening. With this configuration, the air that has passed through the upstream rectifying member stays at an appropriate pressure in the gap with the downstream rectifying member, and the turbulence of the air flow in the gap is suppressed, and flows more reliably to the downstream rectifying member. .

  According to the seventh aspect of the present invention, the planar portions of the rectifying member are disposed on the upstream side and the downstream side of the air flow path from the filter to the work space, and the upstream planar portion is one plate member. 7. The cleaning according to claim 6, wherein the downstream planar portion is formed by folding the same plate and folding a part of the plate on the upstream planar portion. It is a cabinet with an environmental maintenance function.

  In the cabinet with a clean environment maintaining function of the present invention, the rectifying member is formed by bending a single plate. That is, the downstream-side planar portion is obtained by folding the same plate and folding a part of the plate on the upstream-side planar portion. With this configuration, the flow regulating member can be easily formed.

  The folding part of the plate body is on the opening side where the hand of the cabinet with a clean environment maintaining function can be inserted, the folding part also has an opening, and the gap between the planar parts is working space through the opening of the folding part A configuration in communication with is also recommended (claim 8).

  According to the cabinet with the clean environment maintaining function of the present invention, the variation in the wind speed in each part in the work space is highly suppressed, and the work space can be maintained at a desired pressure even if the filter clogging progresses. And cleanliness is maintained.

Hereinafter, embodiments of the present invention will be described.
FIG. 1 is a perspective view of a safety cabinet according to an embodiment of the present invention. FIG. 2 is a perspective view showing the internal structure of the safety cabinet of FIG. FIG. 3 is a front view of the safety cabinet of FIG. FIG. 4 is a partial cross-sectional perspective view of the inner casing and its peripheral members of the safety cabinet of FIG. FIG. 5 is a perspective view showing a work space of the safety cabinet of FIG. FIG. 6 is a perspective view showing a rectifying member and a bent portion. FIG. 7 is a perspective view showing a flow regulating member. FIG. 8 is an explanatory diagram showing the behavior of air when passing through two rectifying members. FIG. 9 is a perspective view showing a rectifying member in another embodiment. FIG. 10 is a perspective view showing a rectifying member in still another embodiment.

A safety cabinet (a cabinet with a clean environment maintaining function) 1 of the present embodiment is a desk shape as shown in FIG. The safety cabinet 1 is mainly composed of legs 2 and a main body 3. As shown in FIG. 2, the main body 3 is provided with an internal housing 6, and the inside of the internal housing 6 functions as a work space 7. The bottom wall 20 of the inner housing 6 functions as the work table 8.
The main body 3 of the safety cabinet 1 has a double structure as shown in FIG. 2, and an air circulation path 10 is formed between the outer portion and the inner housing 6. Blowers 11 and 12 are provided in the main body 3. An opening / closing door 15 is provided on the front surface of the work space 7.
Hereinafter, each of these members will be described sequentially.

  The leg portion 2 functions like a leg of a desk, and in the present embodiment, has two plate shapes. The overall shape of the safety cabinet 1 of the present embodiment is a desk-like shape, and an operator sits on a chair (not shown) to perform an operation, and the operator's feet enter the leg portion 2.

The main body 3 is on the leg 2 and is supported by the leg 2 in a hollow state. The main body 3 has a trapezoidal outer shape as shown in FIGS. 1 to 3, and the front side is inclined by about 10 °. The reason why the inclination of 10 ° is provided is to make the inside of the work space 7 easier to see.
The main body 3 has a double structure as described above, and has an internal housing 6 built therein.
As shown in FIG. 2, the internal housing 6 includes a front wall 18, a bottom wall 20, left and right side walls 21 and 22, a back wall 23 and a top wall 25. The front wall 18 of the internal housing 6 has a large opening in the lower half.
The inside of the internal housing 6 is divided into two stages. That is, the inner housing 6 has an intermediate wall 24 as shown in FIGS. 2 and 4, and a filter 26 and two rectifying members 51 and 52 are mounted on the intermediate wall 24. The rectifying members 51 and 52 are formed by bending one punching metal. The rectifying member 51 and the rectifying member 52 are stacked substantially in parallel. The size of the rectifying member 51 and the rectifying member 52 is substantially the same, and is slightly larger than the size of the filter 26.
A filter 27 is also provided on the top wall 25 of the inner housing 6.
The filters 26 and 27 are both HEPA filters, and have a particle trapping rate of 99.97% or more with respect to particles having a rated air volume and a particle diameter of 0.3 μm.
In FIG. 4, the blowers 11 and 12 and the filter 27 are omitted in order to easily show the positional relationship between the filter 26 and the two rectifying members 51 and 52.
The structure and operation of the filter 26 and the two rectifying members 51 and 52 provided on the intermediate wall 24 will be described later.

In this embodiment, the part below the intermediate wall 24 functions as the work space 7. That is, the space surrounded by the bottom wall 20, the left and right side walls 21, 22, the back wall 23, and the intermediate wall 24 of the internal housing 6 functions as the work space 7.
Further, the bottom wall 20 functions as the work table 8 as described above, and can place an article. Between the bottom wall 20 and the left and right side walls 21, 22, there are air inlets 42, 43 as shown in FIG. Similarly, there is an air inlet 45 between the bottom wall 20 and the back wall 23. An intake port 46 is also provided on the front wall 18 side.
An opening / closing door 15 is provided in the opening 31 on the front surface of the internal housing 6.
The open / close door 15 is obtained by attaching a transparent plate 41 such as glass or acrylic to the frame body 40.
The frame body 40 of the open / close door 15 engages with a slide groove (not shown) and is slidable in the vertical direction.
In the present embodiment, the open / close door 15 is opened and closed by power. The drive mechanism of the open / close door 15 is attached to the front wall 18 of the internal housing 6 as described above.

As shown in FIGS. 2 and 3, blowers 11 and 12 are installed on the upper side of the internal housing 6 (the space above the intermediate wall 24).
A flow path forming wall 33 is provided on the outer side of both side surfaces and the outer side of the back surface of the internal housing 6. That is, as described above, the main body 3 has a double structure, and there is a space on the outside of both side surfaces and the outside of the back surface of the internal housing 6, and the space functions as the air circulation path 10. The air flow path described above communicates with the upper side of the internal housing 6 (a space above the intermediate wall 24) through an opening (not shown).
A filter 27 provided on the top wall 25 of the inner housing 6 communicates with the outside.
A driving mechanism for the door 15 is provided on the front wall 18 of the internal housing 6, and its surface is covered with a decorative plate 35.

The safety cabinet 1 of the present embodiment is characterized in that two rectifying members 51 and 52 are provided on the intermediate wall 24. Hereinafter, the rectifying members 51 and 52 will be described.
Specifically, the rectifying members 51 and 52 are made of a punching metal having a thickness of about 0.3 to 2.0 mm.
That is, the rectifying members 51 and 52 include planar portions 57 and 58 and a large number of circular openings 55 and 56, as shown in FIGS.
Further, as shown in FIG. 6, the rectifying members 51 and 52 are formed by bending one punching metal, and a bent portion 60 is formed. An opening 61 is also provided in the bent portion 60.

The punching metal constituting the rectifying members 51 and 52 has an opening diameter of about 1 mm to 10 mm, and the openings are staggered, and the pitch is about 3 mm to 40 mm. Moreover, the aperture ratio with respect to the whole punching metal is 20%-50%.
The shapes of the openings 55 and 56 are preferably circular, but may be other shapes such as an ellipse and a polygon such as a quadrangle.
In addition, the arrangement of the openings 55 and 56 may be such that the columns and rows of the openings are so-called serial removal, and the columns and rows of the openings are called zigzag. It may be arranged in line.
In the present embodiment, the thickness is 1 mm, the opening diameter is 2 mm, the pitch of the staggered pattern is 3 mm, the aperture ratio is 50%, and the rectifying members 51 and 52 are configured by punched metal with a staggered pattern.

As shown in FIG. 4, the rectifying members 51, 52 are attached to an opening 48 provided in the intermediate wall 24 of the inner housing 6 with screws or the like (not shown).
However, a spacer (not shown) is interposed between the rectifying members 51 and 52, and a gap 53 is provided between the rectifying members 51 and 52.
The distance of the gap 53 is about 2 mm to 20 mm.

As shown in FIG. 7, the rectifying members 51 and 52 are arranged with the positions of the openings 55 and 56 being shifted.
That is, when the rectifying members 51 and 52 are observed from directly above, the opening 55 of the upper rectifying member 51 and the opening 56 of the lower rectifying member 52 overlap each other by about 10% to 80%.

Next, functions of the safety cabinet 1 of the present embodiment will be described. The safety cabinet 1 of the present embodiment performs a dispensing operation or the like in the work space 7 in the same manner as a publicly known one. The safety cabinet 1 is used with the open / close door 15 being half-opened as shown in FIG. A predetermined work is performed by inserting a hand from the opening 70 as shown in FIG.
During this time, the air in the work space is circulated by the blowers 11 and 12 to maintain the work space 7 in a clean environment.
That is, when the blowers 11 and 12 are activated, the air in the work space 7 is sucked from the intake ports 42, 43, 45, and 46 and flows through the air circulation path 10 formed on the side surface and the back surface of the internal housing 6. Enters the upper stage of the internal housing 6 (the space above the intermediate wall 24). A part of the air is exhausted to the outside through the filter 27 provided on the top surface, and the remaining part returns to the work space 7 as clean air via the filter 26 and the rectifying members 51 and 52 provided on the intermediate wall 24. .

Here, in this embodiment, the two rectification members 51 and 52 are provided downstream of the filter 26, and the clean air that has passed through the filter 26 is the two rectification members 51 and 52 provided in the air flow path. Enter the work space 7 after passing through.
Therefore, the clean air supplied to the work space 7 is in a laminar flow state, and the variation in the wind speed distribution is small. Furthermore, the cleanliness of the work space 7 is maintained high.
It is expected that the behavior of air when passing through the rectifying members 51 and 52 is as shown in FIG. That is, FIG. 8 is an explanatory diagram showing the behavior of air when passing through the rectifying members 51 and 52.

A part of the air that has passed through the filter 26 flows into the work space 7 along the baffle plate 63, the front plate 18, and the door 15, but most of the air hits the upstream rectifying member 51 as indicated by the arrows in FIG. , Passing through the opening 55 of the upstream flow regulating member 51. Here, in this embodiment, since the position of the opening 55 of the upstream rectifying member 51 is shifted from the position of the opening 56 of the downstream rectifying member 52, the air that has passed through the opening 55 of the upstream rectifying member 51. A part of the contact portion hits the edge of the opening 56 of the flow regulating member 52 on the downstream side.
Further, since there is a gap between the upstream rectifying member 51 and the downstream rectifying member 52, a space 50 is formed by both.
Therefore, the air that hits the edge of the opening 55 of the downstream rectifying member 52 stays temporarily in the space 50.
As described above, in this embodiment, the space 50 formed between the upstream rectifying member 51 and the downstream rectifying member 52 serves as a buffer space, and the air volume and the wind speed for each opening 56 of the downstream rectifying member 52 are Smoothed.
That is, although the downstream flow regulating member 52 has a large number of openings 56, the air volume and the wind speed introduced into the work space from each opening 56 are substantially the same and have little variation.

  As another effect, it can be said that the air volume and the wind speed are made uniform by changing the air flow path. In other words, in the present embodiment, the positions of the openings 55 and 56 are shifted between the upstream rectifying member 51 and the downstream rectifying member 52, so that the air flow path has a curved path. Therefore, air is mixed in the curved portion, and the wind speed at the individual openings 55 and 56 is made uniform.

  A part of the air that has passed through the upstream flow regulating member 51 enters the opening 61 of the bent portion 60 and flows to the work space 7 as it is. In the present embodiment, when a part of the air flows into the opening 61, the pressure of the space 50 serving as the buffer space becomes appropriate. As a result, the air that has passed through the upstream rectifying member 51 stays in the space 50 with an appropriate pressure, and the turbulence of the airflow in the space 50 is suppressed, and flows more reliably to the downstream rectifying member 52. This is because when the bent portion 60 is closed without the opening 61, the air that has passed through the upstream rectifying member 51 hits the bent portion 61 and rebounds, resulting in disturbance in the air flow in the space 50. Conceivable.

In the above-described embodiment, the same punching metal is used as the upstream rectifying member 51 and the downstream rectifying member 52, but different types of punching metal may be used in the upper and lower directions.
FIG. 9 is a perspective view showing a rectifying member in another embodiment. In this embodiment, a punching metal having a large opening diameter of the opening 55 is used as the upstream rectifying member 51, and a punching metal having a small opening diameter of the opening 56 is used as the downstream rectifying member 52.
FIG. 10 is a perspective view showing a rectifying member in still another embodiment. In the present embodiment, the shape of the opening 55 of the rectifying member 51 is different from the shape of the opening 56 of the rectifying member 52.
Further, punching metals with different arrangements may be used, such as using punched metal in series as the rectifying member 51 on the upstream side and punching metal with zigzag removed as the rectifying member 52 on the downstream side.
Further, the rectifying members 51 and 52 may be made by providing an opening in the resin instead of the punching metal. Further, the means for forming the openings 55 and 56 is not limited to punching metal such as punching metal, and any method such as cutting, casting, die casting, etc. can be employed.

  EXAMPLES Hereinafter, although an Example demonstrates this invention concretely, this invention is not limited to an Example.

  Using a safety cabinet having the same basic configuration as the safety cabinet 1 in FIG. 1, a wind speed comparison experiment in the case where two rectifying members made of punching metal are provided (Example) and one case (Comparative Example). went. The size of the work cabinet of the safety cabinet was 1350 mm wide x 600 mm deep, the size of the HEPA filter outlet was 1170 mm wide x 390 mm deep, and the size of the punching metal was 1344 mm wide x 440 mm deep. The test method was performed in accordance with the test method described in JIS K 3800 “Class II cabinet for measures against biohazard”. That is, in an area that is 150 mm from the wall surface in the vertical and horizontal directions of the work table of the cabinet, it is 200 mm from the lower end of the front panel at the intersection of 3 vertically (AC) and 8 horizontally (1-8). The wind speed (meter / second) of the position was measured. When the measured value of the wind speed at each point was within ± 20% of the average value of the wind speed, it was determined to be appropriate. The measurement position of the wind speed is shown in FIG. In FIG. 11, A is the back side (back wall side), C is the worker side, 1 is the left side, and 8 is the right side, and the worker works in the direction of the arrow.

  Table 1 shows the results when two rectifying members were used (Example). Table 2 shows the results when only one rectifying member was used (comparative example). That is, in the cabinet of the example, the measured value of the wind speed at each point was within ± 20% of the average value of the wind speed and was appropriate. On the other hand, in the cabinet of the comparative example, there were measurement points (2A, 2C, 5C) that deviated from within ± 20% of the average value of the wind speed, which was not appropriate. From the above, when two rectifying members 1 were used, the variation in wind speed was small.

It is a perspective view of the safety cabinet of the embodiment of the present invention. It is a perspective view which shows the internal structure of the safety cabinet of FIG. It is a front view of the safety cabinet of FIG. It is a partial cross section perspective view of the internal housing | casing of the safety cabinet of FIG. 1, and its peripheral member. It is a perspective view which shows the working space of the safety cabinet of FIG. It is a perspective view which shows a baffle member and a bending part. It is a perspective view which shows a baffle member. It is explanatory drawing which shows the behavior of the air at the time of passing through two rectifying members. It is a perspective view which shows the rectification | straightening member in other embodiment. It is a perspective view which shows the rectification | straightening member in other embodiment. It is explanatory drawing of the measurement position of a wind speed.

Explanation of symbols

1 Safety cabinet (Cabinet with clean environment maintenance function)
7 Working Space 11 Blower 12 Blower 26 Filter 51 Rectifying Member 52 Rectifying Member 53 Gap 55 Opening 56 Opening 57 Planar Portion 58 Planar Portion 60 Bending Portion 61 Opening 70 Opening

Claims (8)

  An air flow from a filter to a work space in a cabinet with a clean environment maintaining function that includes a work space having an opening into which a hand can be inserted, a blower, and a filter, and supplies air that has passed through the filter to the work space. A cabinet with a clean environment maintaining function, comprising at least two rectifying members on a road.   The cabinet with a clean environment maintaining function according to claim 1, wherein the at least two rectifying members are plate bodies having a large number of openings.   The cabinet with a clean environment maintaining function according to claim 2, wherein the at least two rectifying members are installed in a state where the positions of the openings are shifted.   The cabinet with a clean environment maintaining function according to any one of claims 1 to 3, wherein an interval is provided between at least two rectifying members.   The cabinet with a clean environment maintaining function according to any one of claims 1 to 4, wherein at least two of the rectifying members are different from each other in at least one of a shape and a size of the opening.   Each of the two rectifying members has a planar portion having an opening, the upper portions of the surfaces are overlapped substantially in parallel with each other, and there is a gap between them. The gap passes through a portion other than the opening. The cabinet with a clean environment maintaining function according to any one of claims 1 to 5, wherein the cabinet is in communication with a work space.   The planar portions of the rectifying member are arranged on the upstream side and the downstream side of the air flow path from the filter to the work space, and the upstream planar portion is a part of one plate body, and the downstream planar shape 7. The cabinet with a clean environment maintaining function according to claim 6, wherein the portion is formed by folding the same plate and folding a part of the plate on the upstream surface portion.   The folding part of the plate body is on the opening side where the hand of the cabinet with a clean environment maintaining function can be inserted, the folding part also has an opening, and the gap between the planar parts is working space through the opening of the folding part The cabinet with a clean environment maintaining function according to claim 7, wherein the cabinet has a clean environment maintaining function.

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