JPH078811A - Sterilizing device for safety cabinet - Google Patents

Abstract

PURPOSE:To provide the sterilizing device capable of smoothly sterilizing the inside of a safety cabinet outside a working space after working. CONSTITUTION:Air is forcibly fed by a fan 11 to a high-performance filter 9 for an air feeding on one side of the working space 6. The other side of the working space 6 is provided with discharge holes 12, 13 through which the air in the working space 6 passes. A communicating path 7 for passing the air flowing out of the working space 6 through these discharge holes 12, 13 is disposed. The leeward side of the fan 11 is provided with a discharge path 14 for discharging the air outside of the body 5 via the high-performance filter 9 for discharge. This communicating path 7 is provided with an ozone generator 22. The discharge path 14 is provided with catalysts 17. An ozone generator 22 is operated in the state of closing an opening/closing door 8 and the fan 11 is run at a low speed below the rated rotating speed. The fan 11 is run at the rated rotating speed in the state of stopping the ozone generator 22.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sterilizing device for a safety cabinet, which forms a working space in a clean environment and prevents microorganisms and bacteria from leaking outside.

[0002]

2. Description of the Related Art Conventionally, this type of safety cabinet has been used to form a working space for handling dangerous samples such as microorganisms and bacteria. For example, Japanese Utility Model Publication No. 54-163.
As disclosed in Japanese Patent Publication No. 95 (B25H1 / 20), most of the air contacting the sample is cleaned by a high-performance filter for air supply and blown out into a work space, and part of the air is exhausted through a high-performance filter for exhaust. The air inside the work space is always kept lower than the outside by guiding the air outside into the work space, so that the air in contact with the sample inside the work space is highly efficient for exhausting the air. It is configured so as not to be discharged outside without passing through the filter.

Further, in order to sterilize the inside of the safety cabinet after the work, a sterilizing lamp has been conventionally installed in the working space, and the working space is sterilized by the ultraviolet rays emitted from the sterilizing lamp.

[0004]

By the way, since the air in contact with the sample also passes through the communication path between the work space and the high-performance filter for air supply, the portion outside the work space is sterilized. However, there has been a problem that the conventional sterilizing lamp cannot sterilize outside the work space.

The present invention has been made to solve the above-mentioned conventional technical problems, and provides a sterilizing apparatus capable of smoothly sterilizing the inside of the safety cabinet main body outside the work space after the work. With the goal.

[0006]

That is, the sterilizing apparatus of the present invention has a cabinet body 5 having an opening / closing door 8 in the front and forming a working space 6 therein, and a feeder provided on one side of the working space 6. High-performance filter 9 for air, blower 11 for sending air to high-performance filter 9 for air supply, and exhaust hole 12 arranged on the other side of work space 6 and through which air in work space 6 passes. , 13, a communication table 7 for sucking the air flowing out of the work space 6 through the exhaust holes 12, 13 by the blower 11, and a high-performance filter for exhaust provided on the leeward side of the blower 11. Cabinet body 5 through 16
The present invention is applied to a safety cabinet 1 having a discharge passage 14 for discharging air to the outside, and an ozone generator 22 is provided in the communication passage 7, and an ozone removing member (catalyst) 17 is provided in the discharge passage 14 to open and close. The ozone generator 22 is operated with the door 8 closed, and the blower 11 is operated at a low speed equal to or lower than the rated speed, and the blower 11 is operated at the rated speed with the ozone generator 22 stopped. It is a thing.

[0007]

According to the present invention, the ozone generator 22 is provided in the communication passage 7 outside the work space 6, and after the work is completed, the ozone generator 22 is operated with the opening / closing door 8 closed to generate ozone. Occur. The generated ozone is circulated in the communication passage 7 by the blower 11, so that the work space 6
The outer communication passage 7 can be sterilized. In particular, since the blower 11 is operated at a low speed equal to or lower than the rated speed during the operation of the ozone generator 22, it is possible to sterilize a relatively wide range while suppressing wasteful ozone generation.

After the ozone generator 22 is stopped and the sterilization by ozone is completed, the blower 11 is operated at the rated speed, so that the ozone contained in the air in the cabinet body 5 is exhausted at a high level. Although it is discharged through the performance filter 16, the ozone removal member (catalyst) 17 is also provided in the discharge path 14 at this time, so that ozone can be quickly removed, and ozone is exhausted with the outside. It can be prevented from being discharged into the air.

[0009]

Embodiments of the present invention will now be described in detail with reference to the drawings. 1 is a perspective perspective view of a safety cabinet 1 to which the present invention is applied, FIG. 2 is a vertical side view of the safety cabinet 1, and FIG.
FIG. 3 is an electric circuit diagram of the safety cabinet 1. Inside the main body 5 of the safety cabinet 1, a work space 6 (work area) opened at the front opening 4 by the partition plate 2 on the back surface and the work table 3 on the bottom surface (on the other side), and below the work space 6. And a series of communication passages 7 (outside of the work area) extending from the back to the upper side, and the opening 4 is closed by an opening / closing door 8 which is vertically movable. A high-performance filter 9 for air supply, which is a HEPA filter, is attached to the top surface (one side) of the work space 6, and a blower 11 made of a sirocco fan is provided above the high-performance filter 9. Has been.

On the other hand, exhaust holes 12 are provided at the front and rear ends of the workbench 3.
13 is formed to connect the lower portion of the work space 6 and the communication passage 7. The blower 11 is operated to pump the air sucked from the communication passage 7 from above to the high-performance filter 9, and a discharge passage 14 communicating with the outside is formed on the leeward side of the blower 11. In the passage 14, a high-performance exhaust gas filter 16 composed of a HEPA filter and a catalyst 17 as an ozone removing member for adsorbing and removing ozone in the air are provided.
And are installed in order. A germicidal lamp 21 that emits ultraviolet rays is installed in the work space 6, and an ozone generator 22 that generates ozone by creeping corona discharge is provided in the communication passage 7.

When the blower 11 is operated with the above configuration,
Most of the air volume QB of the air from the blower 11 is pressure-fed to the high-performance filter 9 as described above, cleaned there, and then blown into the working space 6 from above. Further, a part of the air volume QA passes through the exhaust passage 14, is cleaned by the high-performance filter 16, and is exhausted to the outside after the internal ozone is removed by the catalyst 17. That is, the pressure in the work space 6 becomes lower than the outside by the amount of the air volume QA discharged from the discharge passage 14. Therefore, the same amount of outside air as the air amount QA is sucked from the opening 4 from the outside, and the air amount QA + Q is generated in the working space 6.
It becomes B, passes through the exhaust holes 12 and 13, and flows out into the communication passage 7. The air flowing in from the opening 4 flows from the exhaust hole 12 in the front to the communication passage 7 so that the external air does not come into direct contact with the sample. The air in the communication passage 7 is sucked upward by the operation of the blower 11, and most of the air volume QB is sent to the high-performance filter 9 and part of the air volume QA is sent to the high-performance filter 16.

In this way, the safety cabinet 1 keeps the air to the working space 6 clean by the high-performance filter 9 and keeps the working space 6 at a low pressure from the outside to keep the opening 4 open.
By only sucking the outside air from the inside, it is possible to prevent the air contacting the sample in the working space 6 from directly leaking to the outside from the opening 4, and after it is always cleaned by the high performance filter 16, It is configured to be discharged to the outside.

Next, in the electric circuit of FIG. 3, reference numeral 24 is an inverter device, which is provided on the upper part of the main body 5 and inputs 100 V AC to the input terminals R and T to input the three-phase 20 of a predetermined frequency.
The 0V voltage is output to the output terminals U, V and W. The input terminals R, T of the inverter device 24 are connected to the AC 100V power source via the power switch SW1 of the inverter device 24 and the normally closed contact T2 of the second timer TM2, and the output terminals U, V, W. The blower 11 is connected to. Further, between the COM-X1 terminals of the inverter device 24, one contact of the two ozone switches SW2 and the first contact.
The two normally closed contacts T1 and T1 of the timer TM1 are connected in series.

Here, the inverter device 24 is the COM device.
-When the X1 terminal is open, for example, 50Hz
The blower 11 is constantly operated at a rated speed such as
When the X1 terminals are closed, the blower 11 is operated at a low speed at a low frequency preset to 5HZ, for example. Also,
The ozone switch S is further provided after the power switch SW1.
The first timer TM1 and the second timer TM2 are connected in parallel via the other contact of W2, and the input terminals R and T of the ozone generator 22 are the normally closed contacts T1 of the first timer TM1. The other of T1 is connected through T1. A discharge unit 26 is connected between the output terminals HV and COM of the ozone generator 22. Furthermore, the first and second timers TM1 and TM2 perform an operation of opening the contacts T1 and T2, respectively, after a predetermined timer time t1 and t2 from the time when the first and second timers TM1 and TM2 are energized to start integration. The timer times t1 and t2 of both timers TM1 and TM2 are t2.
> T1, t1 is the sterilization period as described later, and the difference t2-t1 is the exhaust period described later.

Next, the operation of the safety cabinet 1 of the present invention having the above structure will be described with reference to FIGS. 4 and 5. Power switch SW1 and ozone switch SW2 are open (OF
F), the first and second timers TM1,
TM2 closes contacts T1 and T2, respectively. When handling the sample in the work space 6, a power switch S
W1 is closed (ON) and the opening / closing door 8 is opened by a predetermined amount. The inverter device 24 is energized by closing the power switch SW1. At this time, the ozone switch SW2
Is open, the COM-X1 terminals are open, and therefore the inverter device 24 is connected to the 50HZ terminal.
The blower 11 is constantly operated at the rated rotation speed of.

The amount of air discharged from the blower 11 at this time is, for example, 24 m ³ / min, and this amount is the air amount QA + QB.
Is blown out from the blower 11 and most of the air volume QB
Is pumped to the high-performance filter 9 and, as described above, the work space 6
A part of the air volume QA is sent to the high-performance filter 16 and discharged to the outside as described above.

Next, when the work is completed, the opening / closing door 8 is closed and the ozone switch SW2 is closed (ON).
As a result, the first and second timers TM1 and TM2 are energized to start integration, and the ozone generator 22 is energized (ON) by closing the contacts T1 and T1. Ozone is generated from the air passing through the communication passage 7. In addition, when the ozone switch SW2 is closed, the COM-X of the inverter device 24 is closed.
The one terminal is closed (ON), whereby the inverter device 24 operates the blower 11 at a low speed at the frequency preset to 5HZ as described above.

By the low speed operation of the blower 11, the main body 5
An air circulation similar to that described above is formed in the blower 11
Discharge air volume of 2.4 m ³ / min. Further, in this case, since the opening / closing door 8 is closed, the air volume QA flowing into the work space 6 (that is, the amount exhausted from the exhaust passage 14) is only the amount entering through the gap 4A at the upper end of the opening / closing door 8. . Then, due to the low speed operation of the blower 11, the ozone generator 2
Since the ozone generated in 2 is circulated in the communication passage 7,
The inside of the communication passage 7 is sterilized by ozone in the circulating air, and the ozone is supplied from the blower 11 to the high performance filters 9 and 16
Therefore, the high performance filters 9 and 16 are sterilized. Further, since ozone in the air that has passed through the high-performance filter 16 is adsorbed and removed by the catalyst 17, there is no concern that ozone will leak to the outside.

Here, the ozone concentration in the air for performing such ozone sterilization is required to be a value that does not damage the main body 5 and that has the above-described sterilizing action.
Since the amount of ozone discharged from the discharge passage 14 by the blower 11 increases as the number of revolutions increases, the ozone concentration in the air decreases with the same amount of generation. The relationship between the ozone concentration and the rotation speed of the blower 11 according to FIG. 5 is shown. The solid line in the figure shows the measurement result at the side fixed point B in FIG.
The broken line shows the measurement result at the measurement point A. Therefore,
The lower the rotation speed of the blower 11 (extremely stopped) is, the smaller the amount generated by the ozone generator 22 is. However, if the amount of circulating air is too small, the sterilizing effect of ozone generated this time is generated near the ozone generator 22. It will only reach.

According to the present invention, since the blower 11 is rotated at the low speed of 5HZ, the amount of ozone sent to the discharge passage 14 is minimized to suppress unnecessary ozone generation, and the communication passage 7 It is possible to sterilize the entire area of the filter and the high-performance filters 9, 16 and the like. During the sterilization of the communication passage 7 with ozone, the sterilization lamp 21 is also turned on to sterilize the working space 6.

When the timer time t1 of the first timer TM1 elapses after the ozone switch SW2 is closed, the sterilization period ends and the first timer TM1 has both contacts T1, T1.
open. As a result, the electricity to the ozone generator 22 is cut off, so that the operation of the ozone generator 22 is stopped (OF
F) Moreover, since the COM-X1 terminal of the inverter device 24 is also opened (OFF), the blower 11 returns to the steady operation at the rated speed. Therefore, since the circulating air volume in the main body 5 also increases, the exhausted air volume QA also increases, whereby ozone in the main body 5 is quickly sent to the catalyst 17 and removed.

The exhaust period continues until the timer time t2 of the second timer TM2 elapses, and this timer time t
When 2 has elapsed, the contact T2 is opened (OFF). Therefore, since the power supply to the inverter device 24 is cut off, the blower 11 is stopped, and at that point, one cycle of ozone sterilization is completed. After that, when the ozone switch SW2 is opened, the blower 11 is normally operated as described above, so that the sample can be handled again in the working space 6.

[0023]

As described in detail above, according to the present invention, since the ozone generator is provided in the communication passage outside the work space in the safety cabinet body, the ozone generator is connected to the ozone generator with the opening / closing door closed. The ozone generated can sterilize the communication passage outside the work space. In particular, during operation of the ozone generator, the blower is operated at a low speed below the rated speed, so that it is possible to sterilize a wide range over the entire communication passage while suppressing a certain amount of unnecessary ozone generation. is there.

Further, when the ozone generator is stopped,
Since the blower is operated at the rated speed, ozone in the air can be quickly removed by the ozone removal member provided in the discharge path, and the inconvenience of ozone leaking to the outside with exhaust gas is prevented beforehand. Is what you can do.

[Brief description of drawings]

FIG. 1 is a perspective view of a safety cabinet to which a sterilizer of the present invention is applied.

FIG. 2 is a vertical sectional side view of the safety cabinet.

FIG. 3 is an electric circuit diagram of the safety cabinet.

FIG. 4 is a timing chart explaining the operation of the safety cabinet.

FIG. 5 is a diagram showing the relationship between the rotation speed of a blower and ozone concentration.

[Explanation of symbols]

 1 Safety Cabinet 3 Workbench 4 Opening 5 Main Body 6 Working Space 7 Communication Passage 8 Opening / Closing Door 9 High Performance Filter for Air Supply 11 Blower 14 Exhaust Channel 16 High Performance Filter for Exhaust 17 Catalyst (Ozone Removing Member) 22 Ozone Generator 24 Inverter device

Claims (1)

[Claims] 1. A cabinet body having an opening / closing door on the front surface and forming a working space therein, a high-performance filter for air supply provided on one side of the work space, and a high-performance filter for air supply. A blower for sending air under pressure, a workbench disposed on the other side of the work space and having an exhaust hole through which the air in the work space passes, and air discharged from the work space through the exhaust hole In a safety cabinet having a communication passage for sucking by a blower and an exhaust passage provided on the leeward side of the blower for discharging air to the outside of the cabinet main body through a high-performance filter for exhaust, ozone is provided in the communication passage. A generator is provided, an ozone removing member is provided in the discharge passage, the ozone generator is operated with the opening / closing door closed, and the blower is operated at a low speed below the rated speed. In addition, a sterilizer for a safety cabinet, characterized in that the blower is operated at a rated speed while the ozone generator is stopped.