CN111229771A - a fume hood - Google Patents

Abstract

The invention discloses an exhaust cabinet, which comprises a cabinet body, wherein an operation opening is formed in the side of the cabinet body, an air inlet and an air outlet are formed in the top of the cabinet body, and the air outlet and the air inlet are sequentially far away from the operation opening; the perspective sliding door is arranged at the operation opening in a sliding way along the vertical direction; the flow guide threshold is arranged at the bottom of the operation opening and used for allowing air to flow into the cabinet body; wherein, an operation table and a flow guide mechanism which are sequentially far away from the operation opening are arranged in the cabinet body; the top of water conservancy diversion mechanism with the top of the cabinet body links to each other and is located the air exit with between the air intake, the bottom of water conservancy diversion mechanism is higher than the bottom of the cabinet body, the both sides of water conservancy diversion mechanism respectively with the both sides of the cabinet body offset. The exhaust cabinet can effectively exhaust toxic and harmful gas, improve the flow direction of airflow in the cabinet and avoid the toxic and harmful gas from diffusing to the breathing area of workers.

Description

a fume hood

technical field

The invention relates to the technical field of air duct design, in particular to a fume hood.

Background technique

As one of the important equipment for environmental control in chemical laboratories, fume hoods are widely used in laboratories of colleges and universities, government agencies and corporate institutions. When the fume hood is running, the airflow entering the fume hood from the operation port passes through the polluted area on the internal operating table, and the poisonous gas in the polluted area will be discharged from the exhaust port to the outside of the cabinet, so as to avoid the toxic gas staying in the cabinet. , thereby reducing the possibility of toxic gases escaping outward along the exhaust port.

At present, the fume hood is usually designed as a cube structure consisting of an upper cabinet and a lower cabinet. The upper cabinet is a hollow structure, and an exhaust duct and an exhaust fan are arranged on the top of the upper cabinet to ensure the negative pressure state in the cabinet. The operating port of the upper cabinet is provided with a vertically movable sliding door, and the size of the operating port can be controlled by vertically moving the sliding door, and the lower cabinet is a storage space.

However, the boundary of the operation port of the above-mentioned fume hood is prone to gas boundary layer separation, which leads to eddy currents and backflow phenomena, which are not conducive to the flow and efflux of the gas in the cabinet, so that poisonous gases accumulate in the cabinet; The breathing area is located on the upper and outer sides of the operation port, and the airflow in the fume hood has a flow direction from inside to outside and from bottom to top. The gas pollutants in the cabinet are easily diffused to the breathing area of the staff, which is not conducive to the safety of the operator. ; In addition, under the negative pressure of the exhaust fan, the air flow mostly flows into the cabinet from the area close to the sliding door, resulting in a short circuit of the air flow. The effect is poor, resulting in poor removal of toxic gases by the fume hood.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a fume hood, which can effectively discharge poisonous gas, improve the flow direction of the airflow in the cabinet, and prevent the poisonous gas from diffusing to the breathing area of the staff.

In order to achieve the above purpose, the present invention provides a fume hood, comprising: a cabinet body, the side of the cabinet body is provided with an operation port, the top of the cabinet body is provided with an air inlet and an air exhaust port, and the exhaust air Both the port and the air inlet are successively away from the operation port; a see-through sliding door slidably arranged on the operation port in the vertical direction; provided at the bottom of the operation port for air to flow into the cabinet The air guide threshold; wherein, the cabinet is provided with an operation table and a guide mechanism arranged in sequence away from the operation port; the top of the guide mechanism is connected to the top of the cabinet and located at the air outlet Between the air inlet and the air inlet, the bottom of the air guide mechanism is higher than the bottom of the cabinet body, and both sides of the air guide mechanism are respectively abutted against the two sides of the cabinet body.

Preferably, the flow guide threshold is in the shape of an arc plate, and the flow guide threshold has an arc guide hole plate inside the cabinet and an arc guide plate outside the cabinet.

Preferably, both sides of the air outlet are provided with side wall guide posts, the surface of the side wall guide posts is arc-shaped, and the inner ends of the side wall guide posts and the operation port smoothly transition , the bottom of the side wall guide column is connected with the arc guide plate.

Preferably, the bottom of the see-through sliding door is provided with a guide handle, and the included angle α between the guide handle and the see-through sliding door is an obtuse angle.

Preferably, the air inlet is disposed close to the see-through sliding door, the air inlet is elongated and extends along the two sides of the cabinet, and the air inlet is provided with diffuser orifices.

Preferably, it also includes a weight plate connected to the see-through sliding door through a pulley mechanism, and the weight of the weight plate is the same as the total mass of the see-through sliding door and the guide handle.

Preferably, the guide mechanism includes: an inclined guide baffle connected to the top of the cabinet, the inclined guide baffle gradually extending away from the operation port and inclined downward; and the inclined guide baffle The bottom of the plate is connected with vertical baffles, the vertical baffles extend vertically downward.

Preferably, the guide mechanism further comprises a vertical guide orifice plate located on the side of the vertical guide baffle facing the operation port, and the top of the vertical guide baffle is connected to the inclined guide baffle. connected, the bottom of the vertical guide orifice plate is lower than the bottom of the vertical guide baffle plate, and the bottom of the vertical guide orifice plate is provided with a guide bottom plate which is gradually away from the operation port and extends upwards obliquely.

Preferably, the ventilation hole density of the vertical flow orifice plate increases gradually from top to bottom.

Compared with the above-mentioned background technology, in the fume hood provided by the present invention, the airflow direction in the cabinet is improved through the diversion mechanism and the diversion threshold. When the tuyere is activated to generate negative pressure in the cabinet, the airflow at the air inlet will flow down through the operating table to carry the poisonous gas, and then bypass the bottom of the diversion mechanism to discharge the poisonous gas through the air outlet; at the same time, operate The air outside the port enters the cabinet through the diversion threshold, and passes through the operating table and merges with the air flow from the air inlet.

Description of drawings

In order to explain the embodiments of the present invention or the technical solutions in the prior art more clearly, the following briefly introduces the accompanying drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only It is an embodiment of the present invention. For those of ordinary skill in the art, other drawings can also be obtained according to the provided drawings without creative efforts.

1 is a schematic structural diagram of a fume hood provided by the present invention;

Fig. 2 is the front view of Fig. 1;

Fig. 3 is the top view of Fig. 1;

4 is a schematic structural diagram of the interior of a fume hood according to an embodiment of the present invention;

5 is a schematic structural diagram of a flow guide threshold and a side wall guide column according to an embodiment of the present invention;

6 is a schematic structural diagram of a flow guiding mechanism provided by an embodiment of the present invention;

7 is a schematic structural diagram of a see-through sliding door according to an embodiment of the present invention;

Fig. 8 is the airflow direction diagram of a kind of fume hood provided by the present invention;

in,

1-Cabinet, 11-Operation port, 12-Air inlet, 121-Diffusing orifice, 13-Air outlet, 131-Exhaust fan, 2-Perspective sliding door, 21-Direction handle, 3-Direction threshold, 31-Arc-shaped guide plate, 32-Arc-shaped guide plate, 4-Operation table, 5-Guide mechanism, 51-Inclined guide baffle, 52-Vertical guide baffle, 53-Vertical guide hole Plate, 531-guide bottom plate, 54-horizontal connecting plate, 6-side wall guide column, 7-counterweight plate, 8-pulley mechanism, 9-storage cabinet.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

In order to make those skilled in the art better understand the solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

Please refer to FIGS. 1 to 8. FIG. 1 is a schematic structural diagram of a fume hood provided by the present invention; FIG. 2 is a front view of FIG. 1; FIG. 3 is a top view of FIG. 1; Provided is a schematic structural diagram of the interior of a fume hood; FIG. 5 is a schematic structural diagram of a flow guide threshold and a side wall guide column provided by an embodiment of the present invention; FIG. 6 is a guide structure provided by an embodiment of the present invention. Fig. 7 is a schematic structural diagram of a see-through sliding door provided by an embodiment of the present invention; Fig. 8 is an airflow flow diagram of a fume hood provided by the present invention.

As shown in FIG. 1 to FIG. 4 , the fume hood provided by the present invention mainly includes a cabinet body 1 , a perspective sliding door 2 , a flow guide threshold 3 , an operation table 4 and a flow guide mechanism 5 . The structure of the cabinet body 1 is hollow, and an operation port 11 is opened on its side, so that the hands of the staff can enter the cabinet body 1 through the operation port 11. The top of the cabinet body 1 (ie, the top plate) is provided with an air inlet 12 and an exhaust air. The outlet 13, wherein the air outlet 13 and the air inlet 12 are set close to the operation outlet 11 in turn. Preferably, the air outlet 13 has a built-in exhaust fan 131 to maintain a negative pressure state in the cabinet 1, so that the air can pass through the air inlet. 12 and the operation port 11 enter the cabinet 1. Of course, a vacuum device that can generate negative pressure, such as a vacuum instrument connected to the exhaust port 13, can also be installed. In addition, the bottom of the cabinet 1 is provided with a locker 9; The door 2 is slidably arranged on the inner side of the operation port 11 along the vertical direction, so that the staff can adjust the size of the operation port 11 by sliding the see-through sliding door 2; The flow threshold 3 can guide the air outside the cabinet 1 to flow into the cabinet 1, so that the air flows from the outside of the operation port 11 to the inside thereof, thereby preventing the toxic gas in the cabinet 1 from flowing out of the operation port 11. The top surface of the threshold 3 can also reduce the eddy current and backflow caused by the separation of the gas boundary layer at the lower boundary of the operation port 11; During the process, there will be toxic gas at the console 4; the guide mechanism 5 is arranged farther from the operation port 11 than the console 4, and its top is connected to the top of the cabinet 1, and the top of the guide mechanism 5 is located at the exhaust port 13. Between the air inlet 12 and the air inlet 12, the two sides of the air guide mechanism 5 are in contact with the side walls on both sides of the cabinet 1, and the bottom of the air guide mechanism 5 is higher than the bottom plate of the bottom of the cabinet 1, thereby separating the interior space of the cabinet 1. is a U-shaped space.

Here, the working principle of the above-mentioned fume cupboard will be explained: as shown in FIG. 8 , when the exhaust fan 131 or other vacuum devices are activated, the cabinet 1 will generate a negative pressure at the air outlet 13 . The top and both sides of the air guide mechanism 5 are in contact with the inner wall surface of the cabinet body 1, and the gap between the air guide mechanism 5 and the bottom plate of the cabinet body 1 will generate negative pressure, so that the air guide mechanism 5 faces the side of the operation port 11 (including the air inlet port). 12) all the air first flows downward through the operating table 4 and carries the poisonous gas generated by the experiment, then moves towards the above-mentioned gap and then flows upward to bypass the bottom of the diversion mechanism 5, and then continues to flow upward and follows the At the same time, the air outside the operation port 11 will also flow toward the above-mentioned gap through the operation port 11 (that is, flow from top to bottom, from the inside to the outside), so that the cabinet 1 The poisonous gas inside will not escape to the outside of the cabinet 1, thereby ensuring the health and safety of the staff.

In the first embodiment, as shown in FIG. 5 and FIG. 8 , in order to reduce the eddy current and backflow generated at the operation port 11, the guide threshold 3 is designed as an arc, and its arc is preferably 90°, and the operation The inlet surface of the port 11 is the boundary, and the diversion threshold 3 is divided into two parts. , the end of the arc-shaped guide orifice plate 31 and the bottom plate of the cabinet body 1 step transition, preferably, the end of the arc-shaped guide orifice plate 31 and the bottom plate of the cabinet body 1 are connected to the above-mentioned bottom plate at a 90° angle, and the arc The air guide plate 32 is suspended on the outside of the cabinet 1, so that the space below the arc guide plate 32 communicates with the interior of the cabinet 1 through the air holes on the arc guide orifice plate 31. When the cabinet 1 is in a negative pressure state , the air in the space below the arc-shaped deflector 32 will flow into the cabinet 1 through the above-mentioned air holes, so that the airflow at the bottom of the cabinet 1 flows toward the console 4, and the eddy current area at the bottom of the cabinet 1 is eliminated to prevent Avoid the accumulation of toxic gases at the bottom of cabinet 1.

In the second embodiment, in order to reduce the eddy current and backflow generated on both sides of the operation port 11, as shown in FIG. 1 to FIG. 5, both sides of the operation port 11 are provided with side wall guide columns 6. The arc surface of the guide column 6 protrudes outward, one end of the side wall guide column 6 smoothly transitions with the side edge of the operation port 11, and the other end of the side wall guide column 6 expands outward, so that the above-mentioned arc surface The eddy current and backflow caused by the separation of the gas boundary layer can be reduced, and the bottom of the side wall guide column 6 is connected with the arc-shaped guide plate 32, thereby reducing the eddy current and backflow caused by the separation of the gas boundary layer on both sides of the operation port 11. . Preferably, the central angle corresponding to the arc surface of the side wall guide column 6 is an angle of 90°.

In the third embodiment, as shown in FIG. 7 and FIG. 8 , the bottom of the see-through sliding door 2 is provided with a guide handle 21, and the guide handle 21 is for human hands to grasp, so as to adjust the size of the operation port 11 appropriately; In addition, in order to reduce the eddy current and backflow generated on the upper boundary of the operation port 11 , the angle α between the guide handle 21 and the perspective sliding door 2 is an obtuse angle, so that the airflow close to the perspective sliding door 2 passes through the guide handle 21 and is inclined downward. Specifically, the gas in the cabinet body 1 flows toward the console 4 along the upper surface of the guide handle 21, so that the gas outside the cabinet body 1 flows from the bottom end of the see-through sliding door 2 along the side of the see-through sliding door 21. The lower surface flows into the cabinet 1 toward the console 4 , and preferably, the above-mentioned included angle α is set to an angle of 120°.

It should be noted that, in order to avoid eddy currents and backflows occurring anywhere on the upper boundary of the operation port 11 , the width of the guide handle 21 is the same as the width of the see-through sliding door 2 , that is, the guide handle 21 extends to the operation port 11 . on both sides.

In the fourth embodiment, as shown in FIG. 4 and FIG. 8 , the air inlet 12 is arranged close to the perspective sliding door 2 , and the air inlet 12 is elongated and extends along both sides of the cabinet 1 , so that the air inlet 12 The outflowing air flows down close to the perspective sliding door 2 and flows through the above-mentioned diversion handle 21, and prevents eddy currents from being generated inside the perspective sliding door 2; Even if the airflow from the diffuser orifice 121 flows in multiple directions, the airflow can fully flow in the cabinet 1, so as to avoid the airflow dead zone in the top part of the cabinet 1, and ensure that the inside of the cabinet 1 The poisonous gas can be completely discharged.

In the fifth embodiment, as shown in FIG. 1 , FIG. 3 , FIG. 4 and FIG. 8 , the see-through sliding door 2 is connected to a counterweight plate 7 through a pulley mechanism 8 , and the counterweight plate 7 is arranged on the outer side of the cabinet 1 . And located on the opposite side of the operation port 11, the mass of the counterweight plate 7 is equal to the total mass of the perspective sliding door 2 and the guide handle 21, so that the perspective sliding door 2 can stay at any position instantly.

It should be noted that the above pulley mechanism 8 includes a roller and a steel rope, the roller is fixed on the top of the outer side of the cabinet 1, the steel rope is mounted on the roller, and its two ends are respectively connected to the counterweight plate 7 and the see-through sliding door 2.

In the sixth embodiment, as shown in FIG. 4 , FIG. 6 and FIG. 8 , the guide mechanism 5 includes an inclined guide baffle 51 and a vertical guide baffle 52 , wherein the top end of the inclined guide baffle 51 is connected to the The top plate on the top of the cabinet 1 is connected and located between the air outlet 13 and the air inlet 12. The inclined baffle 51 is gradually extended away from the operation port 11 and extends downward; the vertical baffle 52 is arranged vertically and is located in the operation On the side of the table 4 away from the operation port 11 , the top end of the vertical guide baffle 52 is connected to the bottom end of the inclined guide baffle 51 , and the bottom end of the vertical guide baffle 52 is higher than the bottom plate of the cabinet 1 .

In the seventh embodiment, as shown in FIG. 4 , FIG. 6 and FIG. 8 , the above-mentioned guide mechanism 5 further includes a vertical guide orifice 53 , and the vertical guide orifice 53 is vertically arranged and located at the vertical guide block. Between the plate 52 and the console 4, the top of the vertical guide plate 53 is directly connected to the bottom end of the inclined guide baffle 51, while the vertical guide plate 53 is indirectly connected to the inclined guide baffle 51 through the horizontal connecting plate 54. connected to form a one-way air path between the vertical guide orifice plate 53 and the vertical guide orifice plate 53, and the vertical guide orifice plate 53 has ventilation holes for air to pass through, so that the vertical guide orifice plate 53 faces the operation port 11 Part of the gas on one side flows into the one-way air path through the vent hole and flows downward, the bottom end of the vertical guide orifice plate 53 is higher than the bottom plate of the cabinet 1, and the bottom end of the vertical guide orifice plate 53 is provided with a vertical guide. The baffle plate 52 is an upwardly inclined baffle plate 531, wherein the top of the baffle plate 531 should be lower than the bottom end of the vertical baffle plate 52, so that the airflow entering the one-way air path can flow to the vertical baffle plate 52 is away from the side of the operation port 11 , and then flows upward and is discharged from the cabinet 1 along the exhaust port 13 .

It should be noted that, in the vertical direction, the above-mentioned ventilation holes are preferably arranged more densely at the position close to the operating table 4, while the design is relatively sparse in the position far from the operating table 4, that is to say, the above-mentioned ventilation hole density is from top to bottom. It gradually increases at the bottom, and reaches the maximum density in the part close to the operating table 4; the size, shape and distribution of the ventilation holes should be determined according to the actual situation, and will not be introduced in detail here.

It can be seen in combination with all the above contents that the fume hood can avoid the short circuit of the air flow between the air outlet 13 and the air inlet 12, so that the air flow can fully flow through the console 4 and carry the poisonous gas, and the guide mechanism 5 is directed toward the air flow. The flow direction of all the air on the side of the operation port 11 is from top to bottom and from outside to inside; the eddy current area inside the perspective sliding door 2 can be eliminated, so as to avoid the retention of poisonous gas in the above-mentioned eddy current area; it can avoid the inside of the cabinet 1 The gas flows out from the operation port 11, and at the same time, the air flows into the cabinet 1 from the operation port 11, so as to prevent the toxic gas from escaping to the breathing area of the staff.

It should be noted that, in the description of the present invention, the orientations or positional relationships indicated by "upper", "lower", "top", "bottom", "horizontal" and "vertical" used are based on the drawings. The orientations or positional relationships shown are only for the convenience of describing the present invention and simplifying the description, rather than limiting that the indicated elements or parts must have specific orientations, and therefore should not be construed as limiting the present invention.

The fume hood provided by the present invention has been described in detail above. The principles and implementations of the present invention are described herein by using specific examples, and the descriptions of the above embodiments are only used to help understand the method and the core idea of the present invention. It should be pointed out that for those skilled in the art, without departing from the principle of the present invention, several improvements and modifications can also be made to the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

Claims (9)

1. An exhaust hood, comprising:

the cabinet comprises a cabinet body (1), wherein an operation opening (11) is formed in the side of the cabinet body (1), an air inlet (12) and an air outlet (13) are formed in the top of the cabinet body (1), and the air outlet (13) and the air inlet (12) are sequentially far away from the operation opening (11);

the perspective sliding door (2) is arranged on the operation opening (11) in a vertically slidable manner;

the flow guide threshold (3) is arranged at the bottom of the operation opening (11) and used for allowing air to flow into the cabinet body (1);

wherein, an operation platform (4) and a flow guide mechanism (5) which are sequentially far away from the operation opening (11) are arranged in the cabinet body (1);

the top of water conservancy diversion mechanism (5) with the top of the cabinet body (1) links to each other and is located air exit (13) with between air intake (12), the bottom of water conservancy diversion mechanism (5) is higher than the bottom of the cabinet body (1), the both sides of water conservancy diversion mechanism (5) respectively with the both sides of the cabinet body (1) offset.

2. A hood according to claim 1, characterized in that the deflector sill (3) is arc-shaped, and that the deflector sill (3) has an arc-shaped deflector plate (31) inside the cabinet body (1) and an arc-shaped deflector plate (32) outside the cabinet body (1).

3. A hood according to claim 2, characterized in that the side wall flow guiding columns (6) are provided on both sides of the exhaust outlet (13), the surface of the side wall flow guiding column (6) is arc-shaped, the inner ends of the side wall flow guiding columns (6) are smoothly transited to the operation port (11), and the bottom of the side wall flow guiding column (6) is connected to the arc-shaped flow guiding plate (32).

4. A cabinet according to claim 1, wherein the bottom of the sliding door (2) is provided with a guiding handle (21), and an included angle α between the guiding handle (21) and the sliding door (2) is an obtuse angle.

5. A hood according to claim 4, characterized in that the air inlet (12) is arranged close to the sliding door (2), the air inlet (12) is long and extends along the two sides of the cabinet body (1), and a diffusing hole plate (121) is arranged at the air inlet (12).

6. A hood according to claim 4, characterized by also comprising a weight plate (7) connected to the sliding door (2) by a pulley mechanism (8), the weight plate (7) having the same mass as the total mass of the sliding door (2) and the guide handle (21).

7. A fume hood according to any of the claims 1 to 6, characterized in that the deflector means (5) comprise:

the inclined diversion baffle (51) is connected with the top of the cabinet body (1), and the inclined diversion baffle (51) gradually extends downwards away from the operation opening (11) in an inclined mode;

and the vertical flow guide baffle (52) is connected with the bottom of the inclined flow guide baffle (51), and the vertical flow guide baffle (52) vertically extends downwards.

8. A hood as in claim 7, characterized by that, the diversion mechanism (5) further comprises a vertical diversion pore plate (53) on the side of the vertical diversion baffle (52) facing the operation opening (11), the top of the vertical diversion pore plate (53) is connected to the inclined diversion baffle (51), the bottom of the vertical diversion pore plate (53) is lower than the bottom of the vertical diversion baffle (52), and the bottom of the vertical diversion pore plate (53) is provided with a diversion bottom plate (531) which gradually gets away from the operation opening (11) and extends upwards in an inclined manner.

9. A hood according to claim 7, characterized in that the density of the air holes of the vertical deflector plates (53) is gradually increased from top to bottom.

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