JPH0656269B2 - Clean air supply device - Google Patents

Description

TECHNICAL FIELD The present invention relates to an apparatus for supplying clean air to a working space, and in particular, a small bench-type clean working table for experiments and researches in biotechnology such as plant tissue culture. The present invention relates to a clean air supply device suitable for use as.

[Conventional technology]

A conventional cleaning workbench is provided with a shutter that is openably and closably provided on the front side as described in JP-A-59-213438, and a rear view side is provided with a see-through window and an airtight working means. It is composed. This cleaning workbench is a biohazard clean workbench that handles hazardous substances and pathogens that are highly dangerous to the human body, and if this configuration is applied directly to a clean workbench for general work such as plant tissue culture However, the size of the device becomes large and the specifications become excessive, resulting in high cost.

Further, since the cleaning workbench shown in the above-mentioned conventional example is usually large and the depth of the workbench is deep, it is necessary to obtain the illuminance inside the workbench by illuminating a fluorescent lamp or the like provided in this cleaning workbench. Performed exclusively by the device. Since the rear side transparent window is used by the operator to look into the workbench and work, the worker will block the light from the light source in the room where the clean workbench is installed. The technical idea of collecting light from the opened window is not disclosed in the above-mentioned conventional example.

An example of a small tabletop type cleaning workbench is described in JP-A-54-180400 as an example. When such a device is used for experiments such as tissue culture, a gas burner or the like is used for heat sterilization of instruments used inside. Such a conventional small-sized cleaning workbench equipped with a gas burner is composed of a ceiling case 1, a back case 2, a workbench 3, etc., as shown in FIG. This air is supplied into the chamber 7 by the blower 6, secondarily processed and cleaned by the main filter 8, and the clean air 9 is sent into the working chamber 10. A gas pipe 12, an illumination lamp 13 and the like attached to a gas burner 11 used for sterilizing instruments performed in the work room 10 are housed in a back case 2 having a double back plate.

Therefore, the total depth of the clean workbench main body becomes large and the desk 14
There was a problem of occupying a large area when installed on top.

[Problems to be solved by the invention]

The above-mentioned prior art does not consider space saving and has a problem of occupying a large area on the desk. Further, since a flexible pipe (usually a rubber hose or the like) from the rear gas pipe 12 to the gas burner 11 is provided in the workbench, there is a problem that the effective area in the workbench becomes small. Further, if the flexible pipe is shortened, the burner 11 is located behind the work table, which makes it difficult to perform sterilization work. Furthermore, when a sterilization lamp is provided in the workbench for sterilization in the workbench, ultraviolet rays from the sterilization light may deteriorate the flexible pipe and cause gas leakage.

Further, when the conventional clean work table is installed on the wall side of the room, since the gas cock 15 is located on the back side of the back case 2, even if the gas hose connected to the gas cock 15 may come off or break, the work may be performed. Since there is a backside of the table, it is difficult to detect abnormalities and maintenance is difficult, and there is also a risk of causing a serious accident.

Further, the prior art does not give consideration to the work using the microscope in the workbench, and the microscope 16 provided on the workbench 3 is not considered.
Therefore, when the sample is observed, there is a problem that the front surface of the working chamber 10 is opened and there is no pressure difference between the inside and the outside, so that the outside air 4 is easily attracted and the cleanliness of the inside is lowered.

Further, since the illuminating lamp 13 is provided on the wall surface on the back surface of the working room, there is a problem that the distance from the light source to the microscope 16 is long and it is difficult to obtain a sufficient light amount during observation. To solve this problem, the wattage of the illumination lamp 13 (usually a fluorescent lamp) may be increased or the number of lamps may be increased. However, in a small cleaning workbench, there are dimensional restrictions. , I can't simply take this solution. Furthermore, even if this solution solves the problem of light quantity,
Since the calorific value of the illuminating lamp increases, the temperature inside the workbench rises, and there is a problem that the sample dries and the quality changes due to the temperature.

Further, since the observation work with the microscope 16 is performed with the head of the worker 18 entering the work chamber 10, the work is difficult and the work chamber 10 is contaminated by dust emitted from the worker 18. was there.

The object of the present invention is not only excellent in workability and effective utilization of space, but also facilitates maintenance and inspection of gas pipes, and can prevent deterioration of flexible gas pipes to a gas burner due to ultraviolet rays, thus ensuring safety. An object is to provide an excellent clean air supply device.

[Means for solving problems]

The above object is to provide a clean air supply device, a work chamber, a ceiling case which is arranged above the work chamber and stores an air purification element for supplying clean air to the work chamber, and on both side surfaces of the work chamber. Disposed side plates, a back plate disposed on the back side of the work chamber and having a translucent portion, a work opening formed on the front side of the work chamber, an illumination lamp and a sterilizer provided above the work chamber. A lamp and a substantially flat work table arranged below the work chamber and projecting forward from the front of the work chamber are provided, and a gas burner and a microscope are installed in the clean air supplied from the air purification element. A desk-top type clean air supply device in which work is performed, wherein a gas piping unit that stores a gas burner control means is provided on at least one of an outer surface of a ceiling case and an outer surface of a side plate, and the gas burner is controlled by a control means. Connected to A flexible pipe is accomplished by providing movable from the working chamber to the gas piping unit downward.

[Action]

Since the workbench arranged below the work chamber is formed to be substantially flat and has a portion projecting forward from the working opening and on which the microscope is mounted, the microscope is mounted on this projecting portion. It can be installed, and the worker can work without worrying about obstacles such as the ceiling case and side plates. The working opening formed in the front of the working chamber supplies clean air onto the workbench. The front window reduces the opening area of the working opening to accelerate the blowing air velocity from the working opening and cleans the protruding portion by the air curtain action. As a result, the clean air in the work chamber is supplied to the portion of the work table that projects forward from the work opening through the work opening, so that the work with the microscope is performed in the clean air even outside the work room. It can be carried out. The light-transmitting portion provided on the back plate and the illuminating lamp provided above the working chamber on the side of the working opening supply a sufficient amount of light to the microscope to facilitate observation work using the microscope. The lighting lamp is arranged above the work room on the side of the work opening, and the lower end of the ceiling case on the front side of the work room is configured to block the light beam of the lighting lamp so that the light beam enters the eyes of the operator directly. Is prevented, glare is prevented, and workability is improved.

Further, since the gas piping unit that stores the control means of the gas burner is provided on at least one of the outer surface of the ceiling case and the outer surface of the side plate, even if a gas leak occurs, the gas in the working chamber will not be discharged. It can prevent filling and improve safety. Since the gas burner has a flexible pipe connected to the control means and is provided so as to be movable from the working chamber to the lower side of the gas pipe unit, deterioration of the flexible pipe due to the ultraviolet rays of the germicidal lamp can be prevented and safety is improved. While improving, the gas burner and the flexible pipe can be stored outside the work chamber when not in use, and the space in the work chamber can be effectively used.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is a left perspective view of the clean air supply apparatus in this embodiment, FIG. 2 is a right perspective view, FIG. 3 is a back perspective view, and FIG. 4 is a side sectional view.

The clean air supply apparatus in this embodiment has a blower 6, a chamber 7, and a main filter 8 as air cleaning elements inside.
And a work chamber 10 that is a work space to which clean air purified by the main filter 8 is supplied, and a ceiling case 1 having a pre-filter 5 mounted on the upper surface, and both side surfaces of the work chamber 10. The side plate 20, a back plate 21 formed on the back surface of the work chamber 10, and a work table 3 provided on the lower surface of the work chamber 10. The front side of the work chamber 10 is a work opening 1
A front window 22 is provided above the working opening 10a.

The outside air 4 is primarily processed by the pre-filter 5, and the blower 6
Is supplied to and pressurized in the chamber 7, is secondarily processed by the main filter 8 and purified, and is sent into the working chamber 10 as clean air 9 to purify the inside of the working chamber 10. The ceiling case 1 composed of the side plate 20, the back plate 21, the work table 3 and the like is provided with a chamber 7 to make the inside of the case a negative pressure and prevent the inflow of contaminated air from the inside to the working chamber 10. .

In this embodiment, the back plate 21 and the side plate 20 are attached to the ceiling case 1.
The work area of the working chamber 10 is expanded by making the unit and the unit thin, and the loads of the blower 6, the main filter 8 and the like installed above are received by the vertical surfaces of the back plate 21 and the side plates 20 to increase the strength. ing.

The sterilizing lamp 17 located on the rear side of the lower surface of the ceiling case 1 and the illuminating lamp 13 located on the front side are provided at positions on the lower side of the main filter 8 on the side of the clean air outlet so as not to obstruct the flow of the clean air 9. The illuminating lamp 13 is located in front of the lower surface of the ceiling case 1, and the lower end on the front side of the ceiling case 1 blocks the light rays of the illuminating lamp 13 so that the operator can be prevented from glare.

A transparent front window 22 located below the front surface of the ceiling case 1.
In addition to preventing the inflow of the outside air 4, the inside of the working chamber 10 is kept at a positive pressure to obtain a cleaning effect, and the amount of ultraviolet rays emitted from the sterilization lamp 17 is attenuated for safety.

In this embodiment, the workbench 3 is formed so as to project forward from the work chamber 10.

Since the opening area of the work opening 10a is reduced by the front window 22, the blowing air velocity at that portion is increased, and the clean air 9 is obtained also on the workbench 3 protruding forward from the work chamber 10 due to the air curtain action. be able to. FIG. 8 shows an example of use of the cleaning work table, and the cleaning work table is generally placed on the desk 27 for use. Due to the above effects, the microscope 1
It is not necessary to put 6 into the work room 10, the microscope 16 is installed on the work table 3 protruding forward, and work can be performed without worrying about obstacles such as the ceiling case 1 and the side plate 20, thus improving work efficiency and safety. In addition, the contamination from the worker 18 can be prevented. Further, since the clean air in the work chamber 10 is supplied to the portion of the work table 3 which projects from the work opening 10a toward the front, work with a microscope in clean air should be performed even outside the work chamber. The sample can be easily handled and the microscope can be easily operated, and excellent workability can be obtained. Furthermore, even if the worker who was using the microscope suddenly lifted his head,
It is possible to prevent the head from hitting the ceiling of the work room 10 and obtain excellent safety. Further, when the worker 18 sits down on a chair and works, the space below the workbench 3 is widened and workability is further improved. Further, since the workbench 3 projects forward from the work opening 10a,
As shown in FIG. 8, even if the depth of the desk 27 on which the clean air supply device is installed is short, a space for installing the microscope can be obtained, and excellent effective utilization of the space can be obtained.

9 and 10 show a modified example of the workbench located in the lower part of the work chamber 10.

FIG. 9 shows an example in which a movable work table A57 that can slide forward and backward can be stored in the work table 3, and FIG. 10 shows a movable work table B58 that can be lifted up at the front edge of the work table 3. It is a thing. According to the above modified example, since the outer shape of the cleaning workbench can be made small, the room in which the cleaning workbench is installed can be effectively utilized, and the cost of packaging the product can be reduced. Further, since the movable work table B58 of the lifting type can seal the working chamber 10, it is possible to prevent the inflow of contaminants such as dust and insects when not working.

In this embodiment, a back window 23 is provided on the back plate 21 as a light transmitting portion.
Are formed.

FIG. 5 shows an example of the configuration of the back window 23 located on the back surface of the working chamber 10. In this embodiment, the back plate 21 is provided with an opening, and both sides of the translucent plate 23a are pressed by the frame A29 through the packing A28, and the stud bolt 30 and the nut 31.
It is fixed by.

The translucent plate 23a is formed of glass, acrylic, or the like, and particularly, a glass that does not deteriorate due to ultraviolet rays is used in the case where a germicidal lamp is used inside. Translucent plate 2
3a does not necessarily have to be completely transparent, and may be glass such as frosted glass that scatters or diffusely reflects light,
According to this, the light entering the working chamber 10 through the back window 23 becomes almost uniform light over the entire surface, the unevenness of the illuminance in the working chamber 10 is eliminated, and the eyes of the worker are not tired, and the light passes through the back window 23. Since the back side of the work chamber 10 cannot be seen, the worker is not distracted, the work can be performed calmly, and the work efficiency is improved.

Further, if the transparent plate 23a is made transparent, the instructor 5 does not only collect light from the outside but also when work is performed by an unskilled person.
6 can monitor and give instructions from the back and back of the clean work table without disturbing the work.

The translucent plate 23a may be a half mirror,
According to this, when the outside of the work room 10 is bright, the outside light enters the work room 10 to increase the illuminance in the work room, and when the outside of the work room 10 is dark, the light inside the work room 10 is reflected. Then, the amount of transmission to the outside is reduced and the illuminance inside is improved.

6 and 7 show modified examples of the configuration of the back window. FIG. 6 shows a packing B32 which is wound around the opening of the back plate 21 in a frame shape, and a translucent plate 23a is attached therein to form the back window 23. According to this modification, FIG. As opposed to
Costs can be reduced because bolts, nuts, frames, etc. are unnecessary. FIG. 7 shows the translucent plate 23 in the gap of the frame B33 provided around the opening of the back plate 21.
Insert a. This modification can also reduce the cost as described above. Further, in this modification, the translucent plate 23a is detachably provided, so that it can be replaced with a translucent plate having a different light transmittance or transparency depending on the work.

In the present embodiment, the translucent plate 23a does not need to transmit light of all wavelengths, but may be one that transmits light of a specific wavelength or that can absorb light of a specific wavelength. According to this, the wavelength of light and the working room 10
It is possible to study the growth relationship of the plant to be cultivated in the plant, or to control the growth of the plant to be cultivated in the working chamber 10 by transmitting light having a specific wavelength.

In the present embodiment, since it is possible to illuminate the inside of the working room 10 through the back window 23, the lighting lamp 13 inside the working room 10 can be minimized, and the external dimensions of the lighting lamp 13 are small. Therefore, it is possible to effectively use the space in the working chamber 10 without disturbing the clean air flow.

In addition, since the wattage of the illumination lamp 13 in the work room 10 can be small, the amount of heat generated can be small. Particularly, in the clean air supply device used as a small tabletop clean work table, the inside of the work room 10 can be reduced. It is possible to prevent the temperature rise due to the heat generation of the illumination lamp 13. Thereby, the workbench 3 in the work room 10
It is possible to prevent deterioration of the sample placed on it due to drying or temperature rise.

In this embodiment, since the illuminating lamp 13 is provided on the near side of the work chamber 10, the distance from the light source is short and sufficient illuminance can be obtained even when performing work such as observation using a microscope.

When an experiment such as a plant culture is conducted in the working room 10 of the clean air supply apparatus in the present embodiment, instruments such as tweezers used in the working room 10 may be heat sterilized as needed. As a heat source, a gas burner 1
1 is used. In this embodiment, a gas pipe unit 19 which is a heat source control means for controlling the supply of gas to the gas burner 11 is provided, and the gas pipe unit 19 is detachably provided above the outer surface of the clean air supply device.

FIG. 11 shows the external appearance of the gas piping unit 19. As shown in FIG. 13, the gas piping unit 19 is a unit in which a solenoid valve 34 and a piping component 35 are incorporated inside the unit, and a gas cock 15, a foot switch 36, and a power plug 37 are mounted on the outer surface of the unit.

An opening 38 is provided on the outer surface of the unit, and the gas pipe unit 19
If a gas leak occurs in the interior, the gas is released into the atmosphere through the opening 38 to prevent the gas from staying inside and prevent the gas from exploding, and the temperature inside the gas piping unit 19 to rise due to electrical components. There is also an effect to prevent. The openings 38 may be provided on the upper and lower surfaces of the gas piping unit 19. As shown in FIG. 12, the unit and the attachment are fixed to the side surface of the case with a screw 39 using a flange 39. Further, in this embodiment, the left side surface of the case is used, but it can be fixed on any surface of the case depending on the installation conditions of the customer. The gas piping unit 19 can be used for other purposes,
In order to prevent accidents due to different gas types, as shown in FIG. 12, a protrusion 41 having a different shape depending on the gas type is provided on the mounting surface of the unit, and a corresponding receiving hole is provided on the case side as well. It cannot be installed unless the two match. The case can be standardized by providing the protrusions detachably with screws or the like. FIG. 14 is a view showing a state in which the gas piping unit 19 is attached to the left side surface of the case and the gas burner 11 connected to the gas piping unit 19 via the gas hose 26 is used in the working chamber 10. FIG. 15 is a view showing a state when the gas burner 11 is not used. By disposing the gas piping unit 19 on the outer surface of the case as in the present embodiment, the gas burner 11 and the gas hose 26 connected to the gas burner 11 are stored outside the work chamber 10 when the gas burner 11 is not used. The inner space becomes wider, the workability in the room is improved, the work efficiency is improved, and the number of samples can be stored more.

Further, it is possible to prevent the deterioration of the material of the gas hose 26 due to the ultraviolet rays from the germicidal lamp 17.

In this embodiment, since the gas burner 11 is put into the working chamber from the side of the working opening 10a, the gas hose 26 occupies a small area in the working chamber 10 and the gas hose 26 can work even if the gas burner 11 is moved. Since the sample stored in the chamber 10 is not touched, workability and safety are improved. Further, since the gas burner 11 is on the front side, sterilization work is facilitated.

In the present embodiment, by unitizing the heat source control means, it is possible to produce only that unit and reduce the cost, and by stocking the unit as an option, it is possible to promptly shorten the delivery date of the product. Further, as shown in FIG. 15, by making the front dimension w of the gas piping unit 19 larger than the diameter D of the gas burner 11, when a plurality of clean air supply devices of this embodiment are arranged side by side to form a continuous line, The gas piping unit 19 functions as a space holding unit that holds a predetermined space between adjacent clean air supply devices. Further, since the gas pipe unit 19 is provided above the outer side surface of the clean air supply device, it is possible to prevent foreign matter and dust from falling from above into the space formed at a predetermined interval between the clean air supply devices. The space can be used as a storage space for the gas burner 11 when not in operation.

FIG. 17 shows an example in which an opening 20a is provided below the side plate 20 of the cleaning workbench. Due to the positive pressure of the working chamber 10 due to the opening 20a, the clean air 9 is blown out from the opening 20a, and the peripheral portion thereof can be cleaned. As a result, the side of the clean air supply device can also be used as a storage space for sample instruments and the like, and samples and instruments can be stored at a level with a lower pollution level than the outside air.

FIG. 18 shows an example in which the clean air supply device of FIG. 17 is connected. As shown in the figure, at the time of non-working, the blind plate 42 is attached to the opening of the cleaning work table, and the connection space 55 between the devices can obtain a better cleaning effect by blowing clean air from the opening 20a.

It should be noted that the gas burner 11 may be provided with a wind shield (not shown) as necessary to prevent the fluctuation of the flame due to the air flow.

FIG. 16 shows a gas burner 1 used for sterilizing samples and instruments
In this example, an electric heater unit 54 is installed as a heat source instead of No. 1. When this heater is used, a unit for controlling electric power is used instead of the gas piping unit 19 described above.

By using the electric heater unit 54, the heat source for sterilization is not affected by the air flow, so that the handling is easy and no flame is generated, so that the safety is enhanced. In addition, gas piping on the customer side is not needed, cost can be reduced, and oxygen deficiency can be prevented in the installation environment, further improving safety.

FIG. 19 is a diagram showing how a blind plate is attached to the opening of the cleaning work table, and FIG. 20 is a front view when the blind plate is attached.

As shown in this figure, the blind plate 42 used at the time of non-working is formed with the catching holes 44 at the four corners by the grips 45, etc.
Is used by hooking the pins 43 at four positions below the front window 22 and in front of the side plate 20. At the time of work, it is hooked at four positions of the pin 43 located on the front surface of the ceiling case 1. In addition, the pin 43 is provided on the right side surface of the side plate 20 at the same pitch as the blind plate 42.
Are arranged in four places, and can be hooked on the side plate 20 surface.

Only when the blind plate 42 is attached to the front window 22, the interlock switch 46 located in front of the side plate 20 allows the germicidal lamp 17 to be operated.
Can be turned on. As for the circuit, the interlock switch 46 is pushed by pushing down the illumination lamp switch 48 toward the sterilization lamp 17 side and attaching the blind plate 42 as shown in FIG.
By turning on the germicidal lamp switch 47, the germicidal lamp 17 is turned on. In this case, the illumination lamp 13 cannot be turned on.
In this way, it is difficult to understand whether the sterilization lamp 17 is turned on or off when the illumination lamp 13 is turned on because the illumination lamp switch 48 is of a switchable type. It is a thing.

The power supply of the outlet 49 is performed by the fan switch 51.
The fan 6 is turned on by moving the fan motor 50.
The power plug 37 is connected to a foot switch 36 that opens and closes the solenoid valve 34 in the gas piping unit 19 and has a function of interlocking with the. There is.

A modification of the blind plate is shown in FIG. This modification is an example in which a blind plate B59 that can be lifted up is provided below the front window 23. The blind plate B59 is connected to the front window 23 by a hinge or the like, and is lifted up and used in front of the ceiling case 1 when not working. Compared with the above-mentioned separated blind plate 42, it can be handled without being removed, so that it is easy to handle and has good operability.

In the present embodiment, when the electric heater unit 54 is used in place of the gas burner 11 and power control is not required, the side of the clean air supply device is adjacent to the clean air supply device instead of the power control unit. A plate-shaped or box-shaped space holding member (not shown) may be provided to maintain a predetermined space between the device and another device and prevent foreign matter from falling from above.

〔The invention's effect〕

According to the present invention, it is possible to obtain a clean air supply device that is excellent in workability and effective utilization of space and is also excellent in safety.

[Brief description of drawings]

FIG. 1 is a left perspective view of a clean air supply device according to an embodiment of the present invention, FIG. 2 is a right perspective view thereof, FIG. 3 is a rear perspective view thereof, FIG. 4 is a side sectional view thereof, and FIG. Side sectional view of the back window part, No. 6
FIG. 7 is a side cross-sectional view showing a modified example of the configuration of the back window portion in this embodiment, FIG. 8 is a side view showing an example of the usage state of the clean air supply device in this embodiment, and FIG. ,
FIG. 10 is a side view showing a modified example of the workbench part with a partial cross section, FIG. 11 is a perspective view showing the appearance of the gas piping unit in this embodiment, and FIG. 12 is a procedure for mounting the gas piping unit. FIG. 13 is a gas piping diagram in a gas piping unit, and FIGS. 14 and 15 are front views showing a used state and a non-used state of a gas burner of a clean air supply apparatus having a gas piping unit, respectively. Is a perspective view of a clean air supply device provided with an electric heater unit; FIG. 17 is a perspective view of a clean air supply device having an opening in a side plate;
The figure is a front view of the state in which the clean air supply devices of FIG. 17 are arranged side by side, FIG. 19 is a diagram of how to install a blind plate, FIG. 20 is a front view of when a blind plate is installed, and FIG. 21 is a blind plate and a germicidal lamp. 22 is an electric circuit diagram showing an interlock with FIG. 22, FIG. 22 is a side view showing a modified example of the blind plate with a partial cross section, and FIG. 23 is a side sectional view of a clean air supply device of the prior art. 1 ... Ceiling case, 2 ... Back case, 3 ... Workbench
…… Outside air, 5 …… Pre-filter, 6 …… Blower, 7 ……
Chamber, 8 ... Main filter, 9 ... Clean air, 1
0 ... Working room, 11 ... Gas burner, 12 ... Gas piping, 13 ... Illumination lamp, 14 ... Desk, 15 ... Gas cock, 16 ... Microscope, 17 ... Sterilization lamp, 18 ... Worker, 19 ... Gas piping unit, 20 ... Side plate, 21 ...
… Back plate, 22 …… front window, 23 …… back window, 24 …… operation switch, 26 …… gas hose, 34 …… solenoid valve, 35…
... Piping parts, 36 ... Foot switch, 37 ... Power plug, 38 ... Open hole, 39 ... Flange, 40 ... Screw, 41 ... Protrusion, 42 ... Blank plate, 43 ... Pin, 4
4 ... Hook hole, 45 ... Handle, 46 ... Interlock switch, 47 ... Sterilization light switch, 48 ... Illumination light switch, 49 ... Outlet, 50 ... Fan motor, 5
1 …… Fan switch, 52 …… Contactor, 53 ……
52 a contact, 54 ... Electric heater unit, 55 ...
Connection space, 57 ... Movable work table A, 58 ... Movable work table B, 59 ... Blind plate B.

Claims (1)

[Claims] 1. A work chamber, a ceiling case arranged above the work chamber and containing an air purification element for supplying clean air to the work chamber, and a ceiling case arranged on both side surfaces of the work chamber. A side plate, a back plate disposed on the back surface of the working chamber and having a translucent portion, and a working opening formed on the front surface of the working chamber,
An illumination lamp and a germicidal lamp provided above the work chamber,
A gas burner and a microscope are provided in the clean air supplied from the air purification element, the work table being provided below the work chamber and being formed so as to project forward from the front surface of the work chamber. A desk-top type clean air supply device in which work using is performed, comprising a gas piping unit that stores the control means of the gas burner on at least one of the outer surface of the ceiling case and the outer surface of the side plate, The clean air supply device, wherein the gas burner has a flexible pipe connected to the control means and is provided so as to be movable from the working chamber to a lower portion of the gas pipe unit.