JP2000093815A - Clean bench - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a clean bench capable of preventing the scattering of a powdery sample and an undesirable state at the time of using a gas burner and hardly causing an undesirable state such as deterioration of cleanness of a working space in the case when the clean bench is used by other user by allowing outer user to easily know that an air flow controlling function is used by providing the air flow controlling function. SOLUTION: An air flow setting means (air flow controller 23) setting the air flow of a blower lower than a steady operation and an air flow controlling means (air flow controlling part 36) controlling the air flow of the blower to that set with the air flow setting means are provided. Moreover, a display means (air flow controlling operation display light 24) indicating that the air flow controlling means (air flow controlling part 36) is being operated is provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a clean working space formed in a laboratory or a hospital of a university and formed inside.
For example, the present invention relates to a clean bench for performing aseptic operation on a sample such as a powder.

[0002]

2. Description of the Related Art A clean bench of this type is disclosed in Japanese Patent Application Laid-Open No. 7-103331.

[0003] In the clean bench body disclosed in the above publication, a working space is formed inside a casing having an opening in the front, and a stainless steel interior panel is provided inside the casing to form the working space. Are attached to the casing at a predetermined interval. In addition, a workbench is inside the casing bottom plate, and a high-performance (HE
A PA) filter is mounted on the front opening with a slide glass that can be opened and closed vertically. High-performance (HEP) that is attached to the top of the work space and adsorbs dust and bacteria
A) A blower including a sirocco fan and a motor is provided above the filter, and a pre-filter is provided above the blower.

By turning on the switch of the blower, the fan motor rotates at a constant speed, and in this steady operation, purified air is blown into the working space through the high performance (HEPA) filter. As a result, the working space is maintained in a clean state required for the aseptic operation.

A gas burner main flame terminal for connecting a gas burner is provided at a deep portion of a side wall forming a work space.
A gas burner small flame terminal and a gas main cock used for a pilot flame (a pilot flame) are provided so as to face the working space.

[0006] The gas burner is installed on a work bench for the purpose of sterilizing operation rods and the like when performing aseptic operations on samples such as microorganisms in a clean working space of a clean bench.

In the above case, a pilot-fired gas burner is connected to the gas burner main flame terminal and the gas burner small flame terminal via a rubber hose or the like, and is installed on a workbench.

This type of gas burner is originally used for temporarily performing a sterilization operation in a clean work space of a clean bench, and is not used continuously. Therefore, in the case of the above-mentioned pilot-fire gas burner, the pilot-fire is turned on, when the sterilization operation becomes necessary, the gas main valve provided on the side wall of the work space is opened to ignite the gas burner, and when the sterilization operation is completed, the gas main valve is turned off. Will be repeated.

[0009]

However, in the above-mentioned conventional clean bench, since the blower is always driven in a constant operation at a constant rotation speed for the purpose of maintaining the working space in a clean state, the sample is a pharmaceutical product. For powders such as
Depending on the amount of air blown out to the working space, the powder sample may be scattered. Further, even when the gas burner is used temporarily for the sterilization operation, the flame of the gas burner is adversely affected.

Accordingly, the present invention has been made to solve such a problem, and a clean bench capable of preventing scattering of a powder sample and problems at the time of using a gas burner by providing an air volume control function is provided. It is intended to provide.

In addition, the fact that the above-mentioned air volume control function is used can be easily understood by other users, and a problem occurs that the cleanliness of the work space is reduced when other users use the air volume control function. The purpose is not to be.

[0012]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention comprises a blower for blowing purified air into a work space, and reduces the air volume of the blower to less than that in a normal operation. It is characterized by comprising air volume setting means for setting, and air volume control means for controlling the air volume of the blower to the air volume set by the air volume setting device.

[0013] Further, there is provided a display means for indicating that the air volume control means is operating.

[0014]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a schematic vertical sectional view of a clean bench according to an embodiment of the present invention, and FIG. 2 is a front view of a control panel thereof.

In FIG. 1, a work space 4 is formed in a clean bench body 1 inside a casing 3 having an opening 2 in front thereof. Panel 5 is attached to the casing 3 at a predetermined interval. The bottom plate of the interior panel 5 serves as a work table 6, and the upper part thereof serves as a work space 4.

A large number of small air intake holes 7 are formed at the front of the worktable 6, and the air intake holes 7 are formed through a duct 8 formed between the casing 3 and the interior panel 5 through an air inlet of a blower 10 described later. Is in communication with

On the other hand, a high performance (HEP) for adsorbing dust, bacteria and the like in the air blown into the work space 4 and purifying the air blown into the work space 4 is provided on the top of the work space 4.
A) The filter 9a is attached. At the top of the casing 3, a high performance (HEPA) filter 9b, which has a smaller area than the filter 9a, but also cleans air that adsorbs dust and bacteria and blows out to the outside, is attached. . A blower (fan) 10 composed of, for example, a sirocco fan and a motor is provided upstream of these.

Accordingly, when the blower 10 is driven, the inside of the working space 4 is slightly negatively pressured by the amount of air blown out to the outside through the filter 9b at the top of the casing 3, so that the outside air is Is taken in, and the taken-in outside air is filtered by the filter 9a at the top of the work space 4.
The air blown into the workbench 6 is sucked into the intake port 7 at the front of the worktable 6, so that an airflow as shown by an arrow in FIG. 1 is stably formed.

With this configuration, the air in the work space 4 can be kept clean at all times, and the problem that microorganisms, bacteria, and the like handled in the work space 4 are discharged outside can be prevented. It has become.

In the front opening 2 of the work space 4,
A slide glass 11 that can be moved up and down is provided.
At the time of work, as shown in FIG. 1, the work 15 is moved upward and fixed, the hand is put into the work space 4 from here, and the work on the sample 15 placed on the work table 6 through the transparent slide glass 11 can be performed. ing. When the work is not performed, the blower 10 is stopped, and the air in the work space 4 is not cleaned. However, the slide glass 11 is closed, and the germicidal lamp (ultraviolet light) attached to the upper wall of the work space 4 is closed. lamp)
By illuminating 12, it is possible to prevent the propagation of bacteria and the like when not in use.

In this embodiment, the gas supply is controlled by a gas supply solenoid valve (not shown) provided in the gas pipe on the clean bench body 1 side at the lower part of the back wall of the work space 4.
An N / OFF gas terminal (gas supply port) 13 is provided, and an electronic ignition type gas burner can be attached to the gas terminal 13 via a rubber hose.

On the other hand, a control panel 20 as shown in FIG. The control panel 20 has a fan switch 21 for driving the fan 10 and a filter life display for displaying the life of the filters 9a and 9b (= degree of decrease in wind speed) in four stages based on the wind speed on the downstream side of the filter detected by a wind speed sensor (not shown). Light 22, air flow controller 23 capable of continuously (steplessly) adjusting the air flow of fan 10, air flow control operation indicator light 24 indicating that the air is being operated, self-holding gas supply ON switch 25 for setting whether or not to use gas And a gas supply OFF switch 26, a gas supply indicator 27, and the like.

In this embodiment, separately from the control panel 20, a gas supply solenoid valve for turning on / off the gas supply to the gas terminal 13 and an electronic ignition type gas burner connected to the gas terminal 13 are provided. A foot-operated foot switch for turning on / off the gas opening / closing solenoid valve and the igniter (igniter) is provided (not shown).

FIG. 3 shows a circuit related to the air flow control according to the present invention among the electric circuits of the clean bench, and FIG. 4 is a graph showing the correlation between the air flow control by the above circuit and the wind speed value by actually measured values. Things.

As shown in FIG. 3, an AC power supply of 100 V
The respective parts are connected via a fan relay switch 31 interlocked with a fan switch 21 of the control panel 20.

An air volume variable switch 32 and a variable resistor (VR) 33 are provided in conjunction with the air volume controller 23 of the control panel 20. When the air volume controller 23 is fully turned counterclockwise in FIG. 2 (at the time of steady operation), the air volume variable switch 32 is in an OFF state. When the air volume controller 23 is rotated clockwise in FIG. When the switch 32 is turned on, the resistance value of the variable resistor 33 changes.

An air volume variable relay 34 is connected to the air volume variable switch 32 in series with the air volume variable switch 32.
5 is connected in series with the fan relay switch 31.

A of the air volume variable changeover relay switch 35
The contact point is connected to an air flow control operation indicator (L) 24 of the control panel 20, and the contact b is connected to a fan motor (FM) 10a. Accordingly, when the air volume controller 23 is fully turned counterclockwise in FIG. 2 (during steady operation), the air volume variable switch 32 is turned off, the air volume variable relay 34 does not operate, and the air volume variable changeover relay switch 35 is shown in the figure. (Contact b), 100 V AC power is directly supplied to the fan motor 10a, and the fan 10 is driven to rotate at a constant rotation speed (steady operation). On the other hand, when the air volume controller 23 is turned clockwise in FIG. 2, the air volume variable switch 32 is turned on.
As a result, the air volume variable relay 34 operates and the air volume variable changeover relay switch 35 is switched to the a contact, so that the air volume control operation indicator lamp 24 is turned on.

At this time, an output of an AC power supply 100V is controlled to the fan motor 10a via an air volume control unit 36 whose phase is controlled in accordance with the resistance value of the variable resistor 33 (the rotation angle of the air volume controller 23). The rotation speed of the fan motor 10a is controlled continuously (steplessly). The air volume control unit 36 includes a trigger circuit 37
And a well-known circuit comprising a two-way three-terminal thyristor (commonly called triac) 38.

FIG. 4 is a graph of experimental values using the above-described circuit. The horizontal axis represents the percentage (%) of the air volume controller 23 in the control panel 20 with respect to the full dial rotation angle, and the vertical axis represents the average wind speed (%). m / s), and measured at two points: a point 100 mm below the outlet of the working space 4 and a point 254 mm above the worktable. Based on the measurement results, quadratic curve control indicated by a one-dot chain line and a two-dot chain line is obtained. Possible results have been obtained.

Next, the operation of the clean bench of this embodiment configured as described above will be described.

When using the clean bench, first, the fan switch 2 on the control panel 20 shown in FIG.
Turn 1 ON. At this time, the filter life indicator lamp 22 is turned on in accordance with the downstream wind speed of the filter detected by a wind speed sensor (not shown) by the rotation of the fan 10.

During normal operation, the control panel 20
Is fully turned counterclockwise in FIG. 2, and the air volume variable switch 32 in the circuit diagram of FIG. 3 is in the OFF state shown in FIG. Accordingly, as described above, since the air volume variable changeover relay switch 35 is in the illustrated state (contact b), the fan motor 10a is driven at a constant speed, the air volume control operation indicator light 24 is turned off, and the fan 10 Indicates that the vehicle is operating normally.

On the other hand, when a user handles a powder sample which is easily scattered by wind or temporarily uses a gas burner,
When the air volume controller 23 is turned clockwise, the air volume variable switch 32 shown in FIG. 3 is turned on, and the air volume variable changeover relay switch 35 is switched to the contact a.
Are controlled by the air volume control unit 36, and the air volume control operation indicator lamp 24 is lit to indicate that the air volume control function is operating. The degree of air volume control can be confirmed by turning on the filter life indicator lamp 22 of the control panel 20 in four stages. As the air volume controller 23 is turned clockwise, the wind speed decreases as shown in FIG. Therefore, it is possible to effectively prevent the scattering of the powder sample and the trouble at the time of using the gas burner.

By the way, in the above-mentioned air flow control state, for example, when the user is changed to another user for some reason, the air volume is reduced if the user is left as it is. There is a problem that the inside of the space 4 is contaminated with outside air. However, in the present embodiment, the air flow control operation indicator 2
Since the use of the air volume control function can be easily confirmed by turning on the air flow controller 4, a problem that the inside of the work space 4 is contaminated when a new user returns the air volume controller 23 to the original position. Can be reliably prevented.

In the above-described embodiment, the air volume control operation indicator lamp 24 is turned on. However, the air volume control operation indicator lamp may be turned on and off to draw more attention.

[0038]

As described above, according to the present invention, the air volume setting means for setting the air volume of the blower to be smaller than that in the normal operation, and the air volume control means for controlling the air volume of the blower to the air volume set by the air volume setting means With this arrangement, it is possible to effectively prevent scattering of the powder sample and problems at the time of using the gas burner.

Also, a display means for indicating that the air volume control means is operating is provided so that other users can easily understand that the air volume control function is being used. When the user uses the work space, the cleanliness of the work space is reduced, so that it is possible to reliably prevent a problem such as contamination by outside air.

[Brief description of the drawings]

FIG. 1 is a schematic longitudinal sectional view of a clean bench according to an embodiment of the present invention.

FIG. 2 is a front view of a control panel in the embodiment.

FIG. 3 is a circuit diagram related to air volume control of the embodiment.

FIG. 4 is a graph in which the correlation between the air volume control and the wind speed value by the circuit of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Clean bench main body 2 Opening 3 Casing 4 Work space 5 Interior panel 6 Work table 7 Intake hole 9a, 9b High performance (HEPA) filter 10 Blower (fan) 10a Fan motor 13 Gas terminal 15 Sample 20 Control panel 21 Fan switch 22 Filter Life indicator 23 Air flow controller (air flow setting means) 24 Air flow control operation display light (display means) 36 Air flow control section (air flow control means)

Continued on the front page (72) Inventor Tadahisa Saga 2-5-2-5 Keihanhondori, Moriguchi-shi, Osaka F-term (reference) in Sanyo Electric Co., Ltd. 3L056 BD04 BE02 BF04 3L058 BD02 BE08 BF03 BG04 4B029 AA17 4G057 AA02

Claims (2)

[Claims] A blower that blows the purified air into a work space, an air volume setting unit configured to set an air volume of the air blower to be smaller than a steady operation, and an air volume set by the air volume set unit. A clean bench, comprising: an air volume control means for controlling an air volume. 2. The clean bench according to claim 1, further comprising a display unit that indicates that the air volume control unit is operating.