JP2801864B2 - Draft chamber suction air detector - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a draft chamber suction air detector in which the flow of suction air in a draft chamber can be visually confirmed.

[0002]

2. Description of the Related Art Generally, in a draft chamber,
A vertically movable front door is provided at the front opening of the draft chamber body having a working surface inside, and the intake air taken into the draft chamber body from the front opening by the exhaust device is exhausted from the exhaust port. Safety measures have been taken to prevent researchers who conduct various experiments on the work surface from inhaling gases and the like that are harmful to the human body by discharging.

[0003]

The flow of the suction air in the main body of the draft chamber is ensured by operating the exhaust device. The operating state of the exhaust device can be known by turning on a display lamp of the exhaust device provided on the display panel on the front surface.

When the operation switch is turned on, the air discharge device and the display lamp each have a circuit connected to a power supply for the display lamp and the air discharge device. Even if the performance is extremely reduced, the display lamp is turned on.

[0005] In such a case, the display lamp is in a light-on state, but smooth exhaust is not performed in the draft chamber main body, and in some cases, gas or the like flows backward from the front opening where the researcher stands. Since such a situation may occur, there is a problem in terms of safety with the use of the indicator lamp alone.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a draft detector for a draft chamber in which the flow of the draft can be visually confirmed.

[0007]

In order to achieve the above object, the present invention provides a draft chamber body having a working surface inside, a front opening which can be moved up and down at a front opening,
In the draft chamber that discharges the intake air taken into the draft chamber main body from the front opening by the exhaust device to the outside through the exhaust port, the front door is provided with a round hole-shaped opening, while the opening above the opening is provided. A mounting area to be mounted, continuous with the mounting area, the lower half is formed in a semicircular diameter along the opening edge of the opening, and a plurality of vertical slits inserted up to the opening edge of the opening respond to suction air. And a slit region in which the amount of movement varies.

In a preferred embodiment, a colored circular mark portion is provided in the slit area.

[0009]

According to this suction air detector, the operation of the air exhaust device ensures that the intake air is taken into the draft chamber main body from the front open port and is discharged from the exhaust port to the outside.

[0010] When the exhaust device is operated, the slit region of the suction air deformable body is moved inward by the suction air passing through the opening, and by observing the amount of movement, the air volume of the suction air is reduced. You can know. In this case, it can be understood that the amount of movement of the slit area is a strong suction wind when the circular disturbance of the colored circular mark portion is large. In addition, when the circular turbulence is small, it can be easily confirmed visually that the air is weak suction wind.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be specifically described below with reference to FIGS.

In FIG. 1, reference numeral 1 denotes a draft chamber main body of the draft chamber 3, and a front opening 7 is provided with a front door 7 which can move up and down.

The front door 7 is a transparent glass door so that the inside can be observed. The front door 7 is balanced by a balance weight (not shown), and is provided at a lower end edge of the front door 7 with a long handle 9 in the width direction. By being moved up and down, it can be stopped at an arbitrary position.

The inside of the draft chamber body 1 has a work surface 11, and a ceiling is provided with an exhaust port 13 protruding upward.

An exhaust device 15 is connected to the exhaust port 13.
Discharge to the outside via the duct 17 is possible.

The exhaust device 15 can be turned on and off by turning on and off an operation switch 21 provided on an operation panel 19, and the operation lamp 21 lights up when the operation switch 21 is turned on. It has become.

On the other hand, the front door 7 has a round opening 25.
Is provided, and a suction wind deformable body 27 is provided in a region of the opening 25.

As shown in FIG. 3, the suction air deformable body 27 is formed of a thin film having a mounting area 29 and a semi-circular film having a lower half continuous with the mounting area 29 along the opening edge of the opening 25. ing.

The back surface of the mounting area 29 is a bonding surface that can be bonded to the upper part of the opening 25.

The lower part of the mounting area 29 is a slit area 31 formed in a semicircular shape.
3 are inserted up to the opening edge of the opening 25.
Thus, by connecting the ends of the slits 33, the same opening circle as the opening 25 can be obtained as shown by the dotted line in FIG.

The slit area 31 is provided with a colored circular mark portion 35. When the circular mark 35 has a circular state when viewed from the front, it indicates that the suction air is in a zero state. .

According to the draft chamber 3 configured as described above, when the operation switch 21 is turned on, the lighting lamp 23 is turned on, and the exhaust device 15 is in the operating state. By the operation of the exhaust device 15, the intake air taken into the draft chamber main body 1 from the front opening 5 is discharged to the exhaust port 1.
3 is discharged outside through the duct 17.
At the same time, when the exhaust device 15 is operated, when the intake air passes through the opening 25, the slit region 31 moves inward by the intake air. At this time, as shown in FIG. 4, the colored circular mark portion 35, when viewed from the front, has a greatly collapsed circular shape.
While conducting experiments, the flow of the suction wind can be visually checked. In particular, since the amount of movement of the slit region 31 changes in accordance with the amount of suction air, when the amount of movement is small, it can be visually confirmed that the exhaust in the draft chamber main body 1 is not performed smoothly. .

Therefore, even if the lighting lamp 23 is on, an appropriate measure can be taken by observing the movement of the slit area 3.

In this embodiment, the suction air deformable body 27
Is provided on the outside of the front door 7, but it is also possible to provide it on the inside.

[0025]

As described above, according to the present invention, the state of exhaust in the draft chamber main body can be visually confirmed while conducting experiments. Therefore,
Even if the lighting lamp is lit, appropriate measures can be taken promptly, which is very preferable in terms of safety.

[Brief description of the drawings]

FIG. 1 is a perspective view of a draft chamber embodying the present invention.

FIG. 2 is an enlarged sectional view taken along line AA of FIG. 1;

FIG. 3 is a front view of a suction wind deformable body.

FIG. 4 is an operation explanatory view of the suction wind deformable body viewed from the front.

FIG. 5 is an explanatory diagram of the operation of the suction wind deforming body viewed obliquely.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Draft chamber main body 3 Draft chamber 5 Front opening 7 Front door 11 Work surface 15 Air exhaust device 25 Opening 27 Suction air deformable body 29 Mounting area 31 Slit area 33 Slit

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) G01P 13/00 G01F 1/28 G01P 5/04

Claims (2)

(57) [Claims] 1. A vertically movable front door is provided at a front open port of a draft chamber body having a working surface therein, and an exhaust air is discharged from a front open port into the draft chamber body by an exhaust device. In the draft chamber that discharges from the outside, the front door is provided with a round hole-shaped opening, while a mounting area to be mounted above the opening and a mounting area are continuous with the lower half of the opening edge of the opening. It is characterized by providing a suction wind deformable body consisting of a slit area that is formed in a semicircular diameter along and has a slit area where the amount of movement changes according to the suction wind by a plurality of vertical slits inserted up to the opening edge of the opening A draft detector for the draft chamber. 2. The draft detector according to claim 1, wherein a colored circular mark is provided in the slit area.