TWM279718U - Air-isolator fume hood - Google Patents

Description

、 M279,71S VIII. Description of the new type: [Technical field to which the new type belongs] This creation relates to an air curtain type gas cabinet, in particular-a type that can be combined with one side of the cabinet by the valve activity, and the valve system = Another air hood is provided at the same time through the suction groove at the lower edge of the front end of the implant, and-suction population is set, and the suction population corresponds to ^ the air hood setting of the valve is effective to form an air curtain Blocking pollution = Waimao 'and setting up a rectifier network above the cabinet, so as to have both gas extraction and gas supplement mechanism', and perform timely and effective local gas extraction actions near the source of pollution to achieve energy saving, t H, n effectively eliminate And blocking harmful gas rotation and other effects, and is suitable for semiconducting # limbs, a variety of processes in the conductor industry (such as etching resistance, quartz furnace cleaning, etc.), various types of laboratory products structure. [Proprietary technology] The air hood is the main place for local exhaustion. The main operator is to inhale the air containing harmful substances in the form of 疋

official. In order to match the field operating environment, there are many different types of V brother lice cover φ + dagger closed type, sentry box type, Xibnu ^. ^ ^ Self type, blow suction type and receiving type. Among them, the trapping effect of the closed air hood is influenced by the flying environment. Other than M279718. Structure ’is a major obstacle. Because Θ field work often affects or hinders. Therefore, this type of work place is called & Second, it is used for hazardous or extremely high-protection operations, and often requires a high-end guard ^ ^ air hood, Shi Bulai g々 ^, rolling hood is open except one face or open to the outside 隹: the remaining surface of the mouth lb are all Closed to the outside, so its protection and capture

t 1 is better than other non-closed air hoods, and its performance is not easily affected by the external environment. ^ Gang T-type air hood is currently most commonly used in chemical fume hoods (ehemieal f_e "M) used in the laboratory of academic research institutions. There are many processes in the semiconductor industry, such as photoresistance, quartz furnace cleaning, etc. Exhaust cabinet. In recent years, due to the progress of biotechnology, biological hazards have been gradually paid attention to. The bio-safety cabinet used by microbial experimental caterpillars is also based on the π-type air hood. In general, sentry box air hoods are more commonly used in industries with higher safety protection requirements and awareness. Compared with exterior type air hoods, in general, the structure of sentry box air hoods includes surrounding gas cabinets, of which there are still The suction port or the slot of the suction slot must be provided with a baffle that evenly distributes the amount of the exhaust air. A Gangting-type air hood with better protection performance must also be provided with a supply a.ir device. The chemical fume hood, biosafety 7, and M279718 full gas cabinets will be equipped with vertical or horizontal lagoon-type gas hoods with adjustable opening areas. The ultimate goal is to prevent harmful substances in the cabinet from escaping to the outside world. However, in reality Still can not help but have lower operating hazardous substances escaping condition occurs. This problem occurs outline can be divided into three categories ·

1. The design did not reach the most appropriate situation: such as insufficient air extraction volume, improper position of air extraction slots, improper configuration of supplemental air extraction, uneven distribution of wind speed on the opening surface, improper design of opening σ edges, etc. 2. Failure to operate under the most appropriate conditions: if the amount of harmful substances released is too high, the internal harmful substances are released at high speed toward the opening, the excessively large internal operation moves outwards, the sliding door opens and the opening area is too large, and the air extraction volume is not adjusted according to the operating conditions, etc. . 3. Improper maintenance: the wall of the sentry box or the broken pipe has reduced performance. In addition to milk, there are treasures in it. 5% of the material escapes from the air, causing human shells to go out of the road. In some industries, crickets and pubu 7 are collected and biotechnology. Nine considerations must be taken to prevent external air from contaminating the samples in the air hood. Design and performance evaluation are more difficult. The type of the milk cabinet, viewed from the box type 'M279718' in the ancient Renaissance, is mainly due to the natural heat convection effect of the smoke to discharge the bad gas out of the room. At that time, the construction technology of the chimney was not perfect. It was not until the development of fluid mechanics that the technology of using N-air lateral wind air flow was gradually developed to build the smoke self, so that the interior of the chimney formed a local low pressure and the airflow inside the chimney. It is easier to be taken out. The subsequent construction concept of the box-type gas cabinet also followed the ancient box-type gas cabinet, and a ventilation device was added to the upper end of the gas cabinet to force out the gas in the cavity by means of forced convection. The traditional way of gas extraction is to use an exhaust device on the upper end of the gas cabinet to discharge the bad gas in the cabinet. However, similar types of gas cabinets have no systematic classification in the current literature and the use of goods. And the development process of characteristics, after various references and collation, the traditional chemical gas cabinet is mainly divided into two categories: CAV (constant volume air volume) and VAV (variable volume air volume). According to the 'Xi' style chemical gas cabinet, a baffle 2 is installed inside the gas cabinet 1. The floor 2 has a turning angle of 35 degrees near the suction port, at the coordinate position of y 57 and z = 50. There are 3 slots 3 to assist the suction; on the face of the bottom of the baffle 2 y2 57, z = 8 there is a 3cm slit 9 on the wall surface of the coffin plate 2 and the gas cabinet 1, M279718

Auxiliary pumping. The exhaust port at the upper end of the gas tank is connected to the venturi tube, and then connected to the outdoor through a p " talented vent pipe. The 5Hp exhauster 4 (blower) is used to perform the exhaust operation, and the average exhaust flow is approximately fixed at G.5 m3 / s. The purpose of the gas tank 1 is mainly to use the harmful substances generated during the chemical reaction. Before the chemical reaction, the reducer 4 must be operated to perform the air pumping action. At this time, the gas tank H5 * can be completely closed because When the ## 5 valve is complete and there is no supplementary gas mechanism, the motor of the air extractor 4 may idle or even burn. When the operator needs to reach out and operate in the cabinet, the gas cabinet door 5 must be opened to the height required at that time for chemical experiment operation. Here, the maximum opening degree of the gas cabinet door 5 is Hmax = 85cm, and the height of the opening of any gas cabinet door 5 is η: based on the fact that the gas cabinet door 5 is open, there is a concern about the leakage of harmful substances in the cabinet, so To this gas tank! Visualize the laser smoke flow field with the door open. However, although the gas tank has the effect of removing harmful gases generated during the chemical reaction, since the traditional gas tank has not been designed from the point of view of fluid mechanics to improve the structure of the gas tank and the type of pumping, The flow field form of this traditional gas cabinet has obvious large recirculation structure inside the cabinet. Regardless of the opening degree of the cabinet door, these large recirculation structures will form. And, as the opening of the cabinet door decreases, M279718 The range of the reflow structure is increased. Because the 7-flow zone is close to the inside of the cabinet door, the turbulent air flow near the opening of the cabinet door will cause the fluid inside the cabinet door to leak to the outside of the cabinet. Therefore, when the pollutants in the cabinet are mixed in the return area without being evacuated from the cabinet, the pollutants will spread to the outside of the cabinet by the turbulent disturbance near the cabinet door. On the upper level of the gas tank, the level of the smoke on the surface of the _ diffuse diffused flow field shows that in addition to the problem of backflow in the cabinet, there is also a phenomenon that the suction effect is not good. In the flow field near the cabinet: 'In addition to the problem of backflow leakage inside the cabinet door,' there are also obvious leakage and backflow formation near the upper edge of the door and the side wall. In the spatial flow field between the gas tank and the dummy, a return flow is also formed on the dummy's chest. From the perspective of fluid mechanics, the return flow on the dummy's chest is like the flow of fluid flowing behind the blunt body. The airflow of the operator's chest is mixed with the pollutants in the cabinet, and at the same time, the concentration of pollutants in front of the operator is increased. Some of the problems with the poor flow field patterns leading to the leakage of pollutants outside the cabinet are that the traditional gas tank design structure is a very dusty drawn structure. The flow field structure does not consider dynamic fluid dynamics. So in general, 'modification of existing gas tanks to the existing structure' improves the overall flow field of the gas tanks or reduces the leakage of dirty surfaces, which does not happen. The board, the exhaust end, the threshold, the side wall, etc. have been greatly modified. These modifications require a lot of manpower and materials in actual engineering, but they do not necessarily get the corresponding effect. The degree of strict standards, so in actual use still does not meet the needs of users. [New content] The main purpose of this creation is to provide an air curtain type gas box, which is combined with the 榧 々 by the valve activity, is the side of the cabinet, and the valve

The upper part is provided with a blowing hood, # fa] | j}: The IMU seeks the troubles by the suction groove set at the lower edge of the front end of the cabinet, and there is a suction eight port, and the remote suction port is corresponding to the valve blowing. The air hood is installed to form a rolling curtain to effectively block the leakage of pollutants, and the local production of the pollution source is effective and the effective local pumping action is achieved to achieve energy saving, have the exclusive effect of eliminating and blocking harmful gases, and greatly improve The whole only uses health, convenience and security. The second purpose of this creation is to connect the rectifier network installed on the top of an air curtain type air collector of Yishan Zhiyuan to meet the physics of pumping and replenishing air. It has both pumping and lice-reinforcing mechanisms, so that it has the effects of rapid elimination of lactating limbs and energy saving M279718, increasing its practicality and safety. In order to achieve the above purpose, this creation is an air curtain type air cabinet, which includes a cabinet, a valve, an air suction tank, an air extractor and a μ-net. The cabinet body is provided with a accommodating space for excluding harmful gases, and an open space is formed on the side and above of the cabinet body; the valve activity is combined with one side of the cabinet body for controlling the valve opening degree, and the orifice door The upper & have-exhaust hood; the suction trough is provided at the lower edge of the front end of the implant, and is provided with a -suction population, and the inhalation population is provided corresponding to the air hood of the valve; the air extractor It is arranged at the outlet end of the suction tank for the exclusion of treasure gas and σ holes. The δHai rectifier network is set above the cabinet to provide gas supplement; 蕻 丨, corpse &… Wrong, the gas-supply-type gas cabinet can have both the exhaust and replenishment mechanisms, and Zhong Shi: Jiu Jiu did a timely and effective local exhaust action near the source of the dye, and formed a pot to form a rolling curtain to effectively block Exhaust of pollutants, to save energy and effectively discharge and eliminate harmful gases. The above and other projects of this creation /, ′ are not difficult to understand in detail from the following detailed examples of the selected implementation examples: Tian% 代 Β coffee, Tian Tianming and the drawings. Of course, this creation can be different in some different ways or other arrangements, but the iS > Heart Girl Fighter has taken the heart ,,,, and examples as an example. In this manual, Bang elaborated, Xia Ya shows its structure in the drawings. M279718 [Embodiment] Please refer to Figure 3 ~ β 闰 士 ^^^^^ 6. This creation is an air curtain type gas cabinet. The gas curtain type gas cabinet includes: cabinet 10, which is installed inside the cabinet There is a accommodating space that excludes Bao gas, and the side of the cabinet 1 Q and the upper side are: an open space; / a valve 1 1, the valve 丄 丄 activity is combined with the cabinet 0-side, the gas Η 1 丄 is provided with a handle i χ for moving the valve 1 1 and then controlling the valve opening degree. The maximum opening degree of the valve i 为 is Hmax = 60 cm, the height of any valve opening is Η, and the origin coordinate (x, z) of the valve is defined on the middle symmetry plane of the valve, and the valve 1 1 is Equipped with a blow hood ii 2. The supply of blown gas from the valve 11 is mainly controlled by an inverter 16 (blower) and connected to the upper end of the blowing hood 1 1 2 through a flexible pipe. After sections 1 1 3 (honeycombs) and a layer of rectifier network 14, some turbulent energy is dissipated through the stabilization zone and reaches the valve opening zone. A suction tank 12 is arranged at the lower edge of the bottom end of the cabinet body 10, and a suction port 1 2 1 is provided, and the suction σ 1 2 1 is corresponding to the valve 1 1 The blowing hood 1 1 2 is set. M279718 air extractor 1 3, the air extractor 1 3 is arranged at the outlet end of the air suction tank 12 to eliminate harmful gas, so the air extractor 1 3 is equipped with an inverter 15 (inverter) Change and control the speed of the air extractor 1 3, and then control the average speed of valve blowing ... and the average speed Vs of the wearing surface. In addition, the suction machine 3 and the suction

A venturi tube 18 is provided between the outlets of the twelve and 12 to measure the inspiratory speed Vs, and the venturi tube 18 is provided with a pressure transducer 19 (pressure transducer) for optimal profitability. Those who have differential pressure. A rectifier network 14 is arranged above the cabinet 丄 〇 to provide supplemental air; the mesh size of the rectifier network i 4 is 1.5mm × 1.5mm and the wire diameter is 〇3mm.

In addition, the smoke generator 3 0 is powered by the power supply, and the white wax in the smoke generator 3 0 is pressurized by an air dust shrinker, so that the smoke in the smoke generator 3 is released; and the smoke is released; The smoke in the generator 30 is connected to the smoke elbow of the smoke production system through a quick connector, so that the smoke can enter the pollution source controller 70 (smoke ejector), and then gradually diffuse out through the pollution source controller 70. ; With the digital camera 60, it is possible to report the changes in the flow field clearly. In addition, the wind speed converter 50 is used to measure the average M279718 wind speed of the valve blow-out port and the ceiling air supply.

An air curtain type gas cabinet is formed by the above structure. Please refer to Figs. 3 ~ 6. The characteristic of this creation is that it is combined with the reading cabinet body 10-side by the valve masonry activity, and the valve 1 1 is A blower hood 1 1 2 is provided, and the blower 17 is controlled by an inverter 16 and connected to the upper end of the blower hood 丄 i 2 through a winding pipe. The air flows through the rectification section 1 1 3 and a layer of rectifier network i 4 After that, some turbulent energy is dissipated through the stabilization area to reach the valve opening area, and at the same time, the suction groove 12 is set at the bottom of the front end, and a suction port 1 2 1 is provided, and the suction Mouth 1 2 1 is a mouth cover 1 corresponding to the lice gate 1 1; [2 is set to form an air curtain (ie

The air-iSlator with push-puU blow-suction technology can effectively block out the pollutants, and change the position of the exhaust air so as to be close to the source of pollution inside the cabinet to perform an effective local exhaust operation; and Through the rectifier net 14 provided above the cabinet 10, to comply with the physical mechanism of gas extraction and gas supplement; thereby, the breast cabinet can have both gas extraction and gas supplement in time and effectively. In addition to the 'pumping action', it achieves energy saving and effective drainage. Gas, and form a "bad and effective barrier to pollutants, that is, to effectively exclude and block harmful gases, making this 'M279718 creation has the effect of quickly removing, blocking harmful gases and saving energy' plus its practicality, convenience and safety When this creation is used, the flow field inside the cabinet 10 is explained as follows: When the valve opening H / Hmax = 1, Hmax = 60cm, the smoke is released by the valve 11 (by a smoke generator 3) When the laser light page (by the laser light page generator 4) is on the plane of \ = 0 (: 111), the pumping speed Vs = 12 m / s and the blowing speed vb = 2 m / s, the valve 1 1 The blown air curtain will tend to be recessed into the cabinet. When the airflow approaches the exhaust end, it will be pulled by the suction force of the front down suction, and will not continue to be recessed into or out of the cabinet. When the speed Vs 1 2 m / s and the σ popularity speed Vb = 5 m / s, the speed Vb of the airflow is higher than the figure 5_1 (a), so the air curtain flow field blown by the valve ^ 丄 does not have a concave shape. It looks straight; when the speed Vs is 6m / s and the speed Vb = lm / s, the air curtain air flow is concave to the cabinet and is shaped in the cabinet. Cheng Ming Cai's backflow; when the suction speed Vs 1 2 m / s' mouth popularity speed Vb = 6 m / s, the air curtain flow field is straight and an obvious backflow is formed in the cabinet. When the valve opening degree H / Hmax Two three-fourths, Hmax two 60cm, the smoke is released by the valve 1 1 and the laser light page is on the plane M279718 at X = 0cm

on. When the suction speed Vs = 12 m / s and the blowing speed Vb = 2 m / i, the air curtain blown out by the valve 11 will tend to sink into the cabinet. When the air flow approaches the suction end, it will be lowered. The suction force 2 stays' without continuing to sink into the cabinet or flow out of the cabinet; when the suction speed Vs 12 m / s and the blowing speed Vb = 5 m / s, the speed Vb of the airflow is higher than that High ', so the air curtain flow field blown by valve 1 1 has no concave shape and appears straight; when the suction speed Vs = 3 m / s' blowing speed Vb = im / s, the air curtain air flow is concave to the cabinet, and An obvious backflow is formed in the cabinet; when the suction speed Vs = 3m / s and the blowing speed Vb = 5m / s in the cabinet, the air curtain flow field directly forms an obvious backflow. When the valve opening degree Η / Η_ is called / 2, Hmax = 60 cm, the smoke is released by the valve 1 1 and the laser light page is on the plane of X = G em. When the pumping speed Vs = 12m / S, and the blowing speed Vb = im / s, the air curtain blown by the temple valve 1 will have a tendency to sink into the cabinet. When the hole Μ approaches the suction end, it will be sucked down. The suction force pulls 'and does not continue to sink into the cabinet or flow out of the cabinet; when the suction speed m / s and the blowing speed Vb = 4 m / s, the speed Vb of the air flow is higher than that just came' so The air curtain flow field blown out by the valve 1 1 is straight without the shape of indentation. When the suction speed vs = 'M279718 1 m / s and the blowing speed Vb = 0.5 m / s, the air curtain flow is concave toward the cabinet. An obvious backflow is formed in the cabinet; when the suction speed Vs = 1 m / s and the blowing speed vb = 3 m / s, the air curtain flow field is straight and an obvious backflow is formed in the cabinet.

The valve 11 releases smoke, and the laser light page is on the plane of χ = 0 cm. When the suction speed Vs = 12m / s and the blowing speed vb = 2m / s, the air curtain blown by the valve 1 1 will tend to be concave toward the cabinet. When the airflow approaches the suction end, it will be sucked down by the front. Suction pulls' without continuing to sink into the cabinet or flow out of the cabinet; when the suction speed Vb = 5m / S, the speed Vb of the airflow is higher than the previous one, so the air curtain flow blown by the valve u The field appears straight without a concave shape; # Pumping speed Vs = 0.8m / s, when the blowing speed, the air curtain air flow to the cabinet is concave, and a significant backflow is formed in the cabinet; when the pumping speed Vs = 0.8 oil At 0 human lice speed Vb = 3 m / s, the air curtain flow field is straight, and a significant backflow is formed in the cabinet. After practicing the above four valve openings, it can be known that when the operation is not performed, the @, V will cause any backflow in the cabinet. Therefore, the type of the flow field is known. In the use of the κ milk-type gas cabinet, the suction M279718 must be adjusted to avoid the formation of backflow. In addition to knowing whether the flow field in the plant has backflow, the following will further observe the flow field near the threshold of the gas tank at different suction speeds. The flow field pattern near the threshold of the air curtain type gas cabinet is as follows: When the valve opening degree H / Hmax = 1, Hmax = 60cm, the smoke is emitted from the valve 1 1 and the laser light sheet is on the plane of x ^ Ocrn. When the pumping speed Vs = 13.7 m / s and the blowing speed Vb = 3 m / s, no backflow will occur in the cabinet, and the curtain airflow will not flow to the upper edge of the threshold; when the pumping speed Vs = 3 m / s The air blowing speed Vb = 6 m / s. Although Rishou's rolling curtain flow field is straight, a significant backflow has formed in the cabinet, and a backflow has occurred at the upper edge of the gas cabinet door sill. S valve opening H / Hmax = 3/4, Hmax = 60cm, smoke is released by valve 1 1 and the laser light page is on the plane of X = 0 cm. When the suction speed Vs = 12 m / s, the blowing speed Vb = 2 m / s 4 'No backflow will occur in the cabinet, and the air curtain airflow will not flow to the door inspection. 彖' § Only the air speed Vs = 6m / s, blowing speed Vb = 4.5 m / s ^ 'Although the air curtain flow field is straight, it has formed a significant backflow in the cabinet and the upper edge of the gas cabinet threshold. ▲ Valve opening degree H / Hmax = 1/2, Hmax = 60cm, released by factory] 烟雾 1 'laser light page on> == (: 111 plane 20 M279718. S pumping speed Vs = 12 m / s, blowing speed vb = 3 m / s, no backflow will occur in the day, and curtain airflow will not flow to the upper edge of the threshold; when the suction speed Vs is 6m / s, the blowing speed Vb is 3.8m / Although the shang'qixiang flow field is straight, it has formed a significant backflow in the cabinet and the upper edge of the gas cabinet sill. ▲ The valve opening degree H / Hmax = 1/4, Hmax = 60cm, the smoke is released by the valve 1 1 and thunder The light emission page is on the plane of x = 0 cm. When the suction speed Vs = 12 m / s and the blowing speed vb = 3 m / s, no backflow will occur in the temple cabinet, and the curtain airflow will not flow to the door. When the suction speed Vs = 3 m / s and the blowing speed Vb = 2.6 犄, although the air curtain flow field is straight, it has formed a significant backflow in the cabinet and the upper edge of the valve threshold. From the above four valve opening degrees The threshold flow field type can be known, regardless of the opening of the valve, when operating at different blowing speeds, in addition to causing backflow in the cabinet, you can also see the upper edge of the door separately. The flow pattern is generated. If you return to the side-view flow field on the middle symmetry plane, although the air curtain flow field appears straight and there is no backflow in the cabinet, you can see that a backflow is formed on the upper edge of the threshold. Therefore, the air curtain flow field is in the Although there is no backflow formation in the cabinet in a straight state, the backflow is formed on the upper edge of the door plant. Therefore, the flow field pattern near the threshold is 21 'M279718 Known' For the air curtain type gas cabinet, the blowing speed must be adjusted. 'In order to avoid the formation of backflow. However, the change of the suction speed of the gas cabinet will cause many different flow field patterns in the air curtain and the cabinet. These different types of flow fields are easy to feel confused and difficult to grasp the focus. Therefore, it is necessary to sort out a systematic flow field mode through multiple experiments and parameter adjustments to clarify the flow field pattern of the suction air curtain and determine the applicable characteristic area and range. In terms of modal identification, the observed flow field pattern and the related blowing and suction speed are recorded by the flow field visualization technology, and the record is used to make the modal partition of the flow field. private The 'blow-suction' air curtain can be roughly divided into four main modes, the knife type is concave curtain 2 0 (concave curtain), straight mode 2 1 (straight curtain), weak suction mode 2 2 (unde Bu sucti〇n) and over-blow 2 3 (over-blow). In addition to the conditions of these modes, different air curtain flow field patterns are defined, and the ceiling of the gas cabinet is defined as a layer. The rectifier network and pumping position are forward down-suction, domain Η 1 1 release, ㈣, as additional conditions to define these different flow field modes. As far as these four modes are concerned, the concave mode 2 (concave 22 M279718 curtain) 疋 belongs to the four best operating modes of forgiveness. Due to the negative pressure inside the gas cabinet, the airflow brought in by the suction in February ′ J makes the concave curtain air curtain have a pretty, curved shape. When the air curtain is close to the suction end, it will be pulled by the strong suction power of the well-known name and milk mouth, instead of moving around or inside the gas cabinet ^ ^ 9 邛 around ~. So when the valve blows

Vb and front down suction speed and Vs are adjusted to the concave mode to avoid contamination

As for the leakage of dyes, the air curtain protection formed by the opening of the door will be more effective than the simple down-suction gas cabinet. Among the other three modes, the straight mode (straightcurUin) machine type complaint is a mode in which the blowing speed is higher than the concave mode. Although this type of flow field is not easy to generate backflow in the cabinet under the condition of strong suction, the high blowing speed Vb causes the backflow of the upper threshold of the gas tank sill and the turbulent flow field near the valve opening. Although the valve 11 is blowing clean air, the backflow of these upper edges and the chaotic flow field outside the valve all have pollutants leaking out of the cabinet due to turbulent diffusion. The protection of the air curtain is ineffective. In the weak-suction mode 2 2 (under-suction), due to the lack of the lower suction channel, the backflow inside the gas cabinet is caused. Contaminants generated in the gas cabinet will gradually fill the entire gas cabinet 23 with the backflow of the cabinet, and the interior of M279718 ’will be leaked from the ceiling layer of the gas cabinet and near the valve openings in an enlarged manner. In "Ren La Bei 2 3 (〇Ver-bi〇w)", it is a person who belongs to straight mode and weak suction green 绿 ~, ^ a. Backflow in the cabinet due to the lack of the lower suction channel, plus 翕 η 必 a, soil — > The door rolling speed of the door is too south, making the backflow in the cabinet

More serious ’also causes discouraged external chaotic flow fields and backflow of the upper threshold. If it is operated in an over-blowing mode, it is not only unsafe, but also accelerates problems such as backflow and leakage of pollutants. Since these four flow field modalities are mainly based on the speed change as the main adjustment parameter, the zonal maps of the flow field modalities are drawn for different blowing speeds as reference indicators for the operation of the air curtain type gas cabinet. And according to different valve openings, draw the flow field modal division maps of the four valve openings, as shown in Figures 7 to 10. Figures 7 to 10, where two are composed of diagonal lines The speed critical bands with different thicknesses are divided into four modal characteristic regions. If the valve opening degree H / Hmax = 1, the recessed mode 2 in the upper left corner region of the wearer 7 shows that Vs is safe to operate at least 10 m / s or more, but as the blowing speed Vb increases to After about 3.2 m / s, Vs must increase with Vb 24 M279718.

In addition to dividing the two speed critical zones into four different characteristic regions, a single bar can also be used to judge the flow field patterns formed at different blowing speeds. The coarse speed critical band is mainly used to judge whether the airflow blown out of the valve will blow out of the gas tank. That is, the thick speed critical band is used to adjust and control the blowing speed to an appropriate size; the thin critical speed band is mainly used to To determine whether there is a backflow in the cabinet, that is, to adjust and control the suction speed, to avoid a large increase in suction equipment, and waste of energy caused. In addition, as for the modal zoning diagrams of the flow fields of the four valve opening degrees, 'because the valve opening degrees are gradually reduced', the closer the distance between the blowing end and the suction end is, the thin the critical velocity is obviously shifted downward. the trend of. That is, when the valve opening gradually decreases, the suction speed Vs is relatively reduced, and the concave mode 2 can still be operated to avoid the occurrence of pivotal backflow and save energy at the suction side. Based on the flow field modalities and characteristic regions of the above four air curtains, it is recommended to use the area of the concave curtain (cacave curtain) in the operation of the suction speed of the air cabinet. Closed, the display shows that 'this creation can effectively improve the conventional gas cabinet when the ceiling is closed cabinet' phenomenon of backflow (when the conventional gas cabinet ceiling is 25 M279718, no matter what valve opening degree, the cabinet almost all There is a phenomenon of backflow. From the perspective of fluid mechanics, the ceiling of the gas cabinet is closed. The upper layer of the gas cabinet cannot be replenished, which destroys the natural gas replenishment mechanism of the gas cabinet. After the ceiling of the gas cabinet is closed, the air outside the valve is closed. It is the most important source of natural air supply. When the internal gas tank is continuously pumped, the negative pressure is 0 inches. The air flow outside the gas tank will naturally be drawn into the gas tank.

The “returning gradually formed” part, so the backflow inside the gas cabinet is caused by the closed ceiling. The formation of these backflows will mix the pollutants in the hub, and gradually increase the concentration of the pollutants in the cabinet. When the backflow is close to the valve and passes through the valve opening, the pollutants will leak through the molecular diffusion or scattering. Outside the cabinet. Therefore, the design of the gas cabinet ceiling board should be based on not blocking the upper gas supply. ), "No leakage outside the cabinet" and learned from the flow type of the air curtain type armature, there should be a great improvement in the pollutant gas cabinet. The above "compared to the traditional type can be familiar with this technology It is clear that this purpose 'has been in accordance with the above-mentioned details of the Patent Law, and the creation can indeed achieve the aforementioned determination, and then file a patent application. The above mentioned ones are only for this creation, # · The preferred embodiment has been used by Tian Bu This restricts the implementation of this creation. Therefore, any simple equivalent changes and modifications made in accordance with the scope of the patent application and the contents of the creation specification of 26 M279718 for this creation shall still fall within the scope of this creation patent.

27 'M279718 [Schematic description] Figure 1 is a schematic plan view of a conventional embodiment. FIG. 2 is a schematic side view of a conventional embodiment. Fig. 3 is a three-dimensional appearance view of this creative embodiment. Figure 4 is a schematic plan view of this creative embodiment. FIG. 5 is a schematic side view of this creative embodiment. _ Figure 6 is a schematic diagram of the use of this creative embodiment. Figures 7 to 10 are modal partition maps of the flow field in this creative embodiment. [Description of main component symbols] 1. Gas cabinet 3, slot 5, gas cabinet door 1 0, cabinet 1 1 1. handle 1 1 3. rectifier section 1 2 1. suction port 1 4. rectifier network 1 6. inverter 1 8. Venturi tube 2. Slot plate 4. Extractor 1 1 Valve 1 1 2. Blow hood 1 2. Suction tank 1 3. Extractor 1 5. Inverter 1 7. Air blower 1 9 , Pressure conversion meter 28 M279718 2 〇, concave mode 2 2, weak suction mode 3 0, smoke generator 5 0, wind speed converter 7 0, pollution source controller 1, straight mode 3, over blowing mode 0 , Laser light page generator 0, Digital camera

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Claims (1)

M279718 IX. Scope of patent application: 1. An air curtain type gas cabinet, which includes: a pivot body; the cabinet body is provided with a accommodating space for excluding harmful gas, and one side of the plant body and above It forms an open space; a valve, which is movably combined with one side of the cabinet for the opening of the door, the valve is provided with an air blowing hood; the suction trough 9 child suction trough is located at the front of the cabinet At the lower edge, there is an "XZ u" inlet, and the suction port is set to correspond to the air blowing of the valve; m The air extractor is arranged at the outlet end of the suction tank to exclude harmful gases; and = Drift network, the rectifier network is located above the cabinet to provide gas supplement; :::: The air supply curtain air planting can have both the air extraction and gas supplementation mechanisms, and the local exhaustion of the ancient μ μ can be performed in time near the source of the dye, and the air-inhibiting and effective blocking of pollutants ... Gas person. With regard to energy saving and effective exclusion, the air curtain type gas tank described in the first patent is covered with a handle, and the air curtain type gas tank is described by 0.1 members. Among them, it is used to move the name of the snail door and control the valve opening degree by 30. 2. 'M279718 Shenyue Patent Qianwei's air curtain type gas cabinet, wherein the air extractor changes and controls the speed of the air extractor with a very weeping and frequent inverter to control the average valve blowout. The speed Vb and the average speed Vs of the inhalation face. The air curtain type gas cabinet according to the above item, wherein the I5mmxl.5mm and the wire diameter is 03mm 4 The mesh size of the rectifier net is 0. 5. The air curtain type gas cabinet described in item 1 of the scope of patent application, wherein the maximum opening degree of the valve is Hma ... "m, and the height of any valve opening is 的 Η The origin coordinate (χ, ζ) is on the middle symmetry plane of the gas tank. 6. The air curtain type gas tank as described in the patent application scope No. 1 which controls the air blower for the air blower in the valve, in which this aspect should It is mainly driven by a frequency converter (blower) and connected to the upper end of the blowing hood through a winding tube. The airflow passes through the honeycombs and -layer rectification network, and then dissipates part of the turbulent energy through the stabilization zone to reach Valve opening area. M279718 7. The air curtain type gas cabinet according to item 1 of the patent application scope, wherein a venturi tube is provided between the air extractor and the outlet end of the suction tank for measuring suction The air velocity Vs, and the Venturi tube system is provided with a pressure transducer to obtain the pressure difference. 32