CN203678806U - Exhaust cabinet - Google Patents

Abstract

An exhaust cabinet comprises a hollow cabinet body, wherein a cabinet door is arranged at the front end of the cabinet body, an air inlet opening is formed at the bottom end of the cabinet door, the cabinet body is connected with an air extractor for extracting harmful gas in the cabinet body, a boundary layer control plate which faces the rear side of the cabinet body and extends horizontally and obliquely downwards is arranged on the lower edge of the cabinet door, when gas enters the cabinet body from the opening, a first boundary layer separation point and a multiple contact point can be formed on the boundary layer control plate, and the distance of the oblique extension of the boundary layer control plate is greater than the distance between the first boundary layer separation point and the multiple contact point. Therefore, when air enters the cabinet body through the opening at the bottom end of the cabinet door, harmful gas in the cabinet body is prevented from leaking outwards from the lower edge of the cabinet door.

Description

exhaust cabinet

technical field

The utility model relates to an exhaust cabinet, in particular to an exhaust cabinet which can effectively prevent harmful gas from leaking from the lower edge of the cabinet door, and is suitable for factories, laboratories and commercial kitchens.

Background technique

The extraction method of the traditional exhaust cabinet is to set up an opening shutter on the upper end of the cabinet, and erect a deflector with a specially designed opening at the rear of the cabinet, and pass the harmful gas in the cabinet through the exhaust device and the duct. The opening of the upper shutter and the opening of the deflector at the rear of the cabinet are drawn out.

However, the door of the general exhaust cabinet is a vertical plate, as shown in Figure 5, when the air extraction device a is activated to suck the air flow into the exhaust cabinet through the opening c at the bottom of the cabinet door b, the air flow will A boundary layer separation point d is formed at the bottom edge of the cabinet door b, and because the boundary layer separation point d is too close to the opening c at the bottom of the cabinet door b, the harmful gas will be rolled by the large return bubble e behind the cabinet door b to the adjacent The position of the opening c at the bottom of the cabinet door b is easily affected by factors such as people moving around, external interference air flow or turbulent flow diffusion, allowing harmful gases to leak outward from the bottom of the cabinet door b.

As shown in Figures 6, 7, and 8, an arc-shaped and upwardly curved deflector f is provided in front of the bottom of the cabinet door b or an arc-shaped and upwardly curved deflector half is provided behind the bottom of the cabinet door b. Circular plate g to guide the airflow into the cabinet. However, due to the basic reasons of aerodynamics, the large return bubble e will still be rolled to the opening c near the bottom of the cabinet door b, and it is also difficult to prevent the harmful gas in the cabinet from leaking outwards.

Contents of the invention

In view of this, in order to provide a structure different from the prior art and improve the above-mentioned shortcomings, the creators have accumulated many years of experience and continuous research and development, so the utility model is produced.

An object of the present utility model is to provide an exhaust cabinet. The bottom end of the cabinet door is provided with a boundary layer control panel facing the rear side of the cabinet and extending horizontally and downwards, so as to solve the problem of existing exhaust gas. The harmful gas in the cabinet leaks from the bottom of the cabinet door, and the large return bubble can be kept away from the bottom of the cabinet door to reduce the probability of harmful gas leakage.

In order to achieve the purpose of the above creation, the exhaust cabinet provided by the utility model includes a hollow cabinet body, the front end of the cabinet body is provided with a cabinet door, and the bottom end of the cabinet door forms an opening for air intake, and the cabinet body is connected to an air extraction device , for extracting the harmful gas in the cabinet, the main technology is that the bottom end of the cabinet door is provided with a boundary layer control panel facing the rear side of the cabinet and extending horizontally and downwards. When the gas enters the cabinet through the opening, the front edge of the boundary layer control plate forms a first boundary layer separation point, and a complex contact point is formed on the boundary layer control plate downstream of the first boundary layer separation point, and the boundary layer control plate extends obliquely The distance of is greater than the distance between the first boundary layer separation point and the complex contact point.

During implementation, the boundary layer control board is a rectangular board, and one long side of the boundary layer control board is combined with the bottom end of the cabinet door.

During implementation, an arc-shaped plate is extended from the other long side of the boundary layer control plate.

For the convenience of having a deeper understanding of the utility model, it is described in detail below:

Description of drawings

Fig. 1 is a side sectional schematic view of a preferred embodiment of the present utility model;

Fig. 2 is a schematic side sectional view of another implementation state of the present utility model;

Fig. 3 is the use state diagram of the preferred embodiment of the present utility model;

Fig. 4 is the correlation graph of the width and inclination angle of the boundary layer control plate of the present utility model;

Figures ^5-8 are schematic diagrams of the use states of different doors of the existing exhaust cabinets when passing harmful gases.

Explanation of reference signs

Exhaust cabinet-1; cabinet body-2; bottom plate-21; top plate-22; through hole-221; exhaust device-222; Boundary layer control plate-3; arc plate-31; first boundary layer separation point-A; complex contact point-B; second boundary layer separation point-C; between the first boundary layer separation point and complex contact point Distance-Lr; Angle of downward slope of the boundary layer control plate horizontally-θ.

Detailed ways

The utility model exhaust cabinet comprises a hollow cabinet body, the front end of the cabinet body is provided with a cabinet door, and the bottom end of the cabinet door forms an opening for air intake, and the cabinet body is connected with an air extraction device for extracting harmful gases in the cabinet body. The bottom end of the cabinet door is provided with a boundary layer control panel facing the rear side of the cabinet body and extending horizontally downwards. The distance of the boundary layer control panel's oblique extension is greater than the distance between the first boundary layer separation point and the complex contact point.

Please refer to FIG. 1 , which is a preferred embodiment of an exhaust cabinet 1 of the present invention, including a cabinet body 2 and a boundary layer control panel 3 .

The cabinet body 2 is a hollow cuboid composed of a base plate 21 , a top plate 22 , a left side plate 23 , a right side plate, a rear plate 24 and a cabinet door 25 . A through hole 221 is formed on the top plate 22, and the through hole 221 is connected with an air extraction device 222, so as to remove the air in the cabinet body 2 when the air extraction device 222 is running. The cabinet door 25 is arranged at the front end of the cabinet body 2 and can be pulled up or down by the user. The bottom end of the cabinet door 25 forms an opening 26 for air intake.

The boundary layer control panel 3 is a rectangular flat plate, including two long sides and two short sides, wherein one side long side of the boundary layer control panel 3 is combined with the bottom edge of the cabinet door 25, and the boundary layer control panel 3 faces the cabinet. The rear side of the body 2, and extends downward at an angle of θ with the horizontal. During implementation, the boundary layer control panel 3 can also be a rectangular aluminum extruded plate connected to the edge of the bottom end of the cabinet door 25 as shown in Figure 2, or welded, locked or clipped to the bottom end of the cabinet door 25 in sections The edge is a flat plate, and an upwardly curved arc-shaped plate 31 extends from the other long side of the boundary layer control plate 3 .

Please refer to Figs. 1 and 3, the distance between the short sides of the boundary layer control plate 3, that is, the width of the boundary layer control plate 3 is greater than the distance between the first boundary layer separation point A and the complex contact point B. The actual width of the boundary layer control panel 3 is determined according to the curve in Fig. 4, wherein, Lr is when the gas enters the cabinet body 2 from the opening 26, the first boundary layer separation point A and the complex contact point A are formed on the boundary layer control panel 3. The distance between points B, and θ is the angle at which the boundary layer control plate 3 is horizontally inclined downward. During implementation, the boundary layer control plate 3 can also be a plate body such as a rectangular arc plate, and the second boundary layer separation point C can also be formed at the tail end of the boundary layer control plate 3 .

Thus, as shown in Figure 3, when the air enters the cabinet body 2 through the opening 26 at the bottom of the cabinet door 25, based on the basic principle of aerodynamics, a first boundary layer separation will be formed on the boundary layer control panel 3. Point A and a complex contact point B form a separation bubble between the boundary layer separation point A and the complex contact point B. Because the width of the boundary layer control plate 3 is greater than the distance between the first boundary layer separation point A and the multiple contact point B, at the downstream of the multiple contact point B, the airflow will flow downstream along the boundary layer control plate 3, and this airflow After flowing to the position of the downstream end of the boundary layer control board 3, it will be separated again, forming a second boundary layer separation point C, and forming a large reflux bubble behind the cabinet door 25 and above the boundary layer control board 3. And because the position of the second boundary layer separation point C downstream of the boundary layer control plate 3 is far away from the opening 26 at the bottom of the cabinet door 25, the harmful gas entrained by the large backflow bubble can be prevented from leaking outwards from the opening 26.

Therefore, compared with the traditional exhaust cabinet, the utility model can solve the problem that the harmful gas in the existing exhaust cabinet leaks outward from the bottom of the cabinet door, and can keep the large return bubble away from the bottom of the cabinet door, so as to Reduce the chance of harmful gas leakage.

The above description of the utility model is illustrative rather than restrictive. Those skilled in the art understand that many modifications, changes or equivalents can be made to it within the spirit and scope of the claims, but they will all fall into Within the protection scope of the present utility model.

Claims (3)

1. an exhaust gas cabinet, comprises the cabinet of a hollow, and the front end of this cabinet is provided with a cabinet door, and the bottom of this cabinet door forms the opening of an air inlet, and this cabinet connects an air extractor, for the pernicious gas of extracting out in cabinet, it is characterized in that:

The bottom of this cabinet door is provided with one towards cabinet rear side, and the boundary layer control panel of the downward-sloping extension of level, in the time that gas enters in cabinet by opening, on this boundary layer control panel, form a first side interlayer burble point and multiple connection contact, and the distance that this boundary layer control panel tilts to extend is greater than the distance between this first side interlayer burble point and this multiple connection contact.

2. exhaust gas cabinet as claimed in claim 1, is characterized in that, this boundary layer control panel is a rectangular slab, and the long limit of a side of this boundary layer control panel is incorporated into the bottom of this cabinet door.

3. exhaust gas cabinet as claimed in claim 2, is characterized in that, an arc is extended on the long limit of opposite side of this boundary layer control panel.

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