Ventilation cabinet for laboratory

Abstract

A ventilation cabinet for a laboratory comprises a cabinet body, a window, a working table top, a lifting cabinet door, an air collecting cover and an exhaust pipe, the window is formed in a panel of the cabinet body, the ventilation cabinet further comprises a first air knife, a bottom plate and a front baffle, the first air knife is installed on the inner wall of the cabinet body above the window, and the bottom plate is of an L-shaped structure formed by bending a head section, a middle section and a tail section; the middle section is fixedly connected to the working table top through a plurality of first guide strips, a first gap is formed between the head section and the cabinet body back plate, a second gap is formed between the tail section and the cabinet body panel, the front baffle is fixedly connected to the cabinet body back plate through a plurality of second guide strips, and one end of the head section is located in the gap between the front baffle and the cabinet body back plate. And the air outlet direction of the first air knife is upward. The ventilation cabinet door opening device is used for solving the problem that poisonous gas floats out of a window when a ventilation cabinet door is opened.

Description

A laboratory fume hood Technical Field

[0001] This utility model relates to a laboratory fume hood. Background Technology

[0002] In modern scientific research, teaching, and various experimental settings, fume hoods are widely used as essential experimental equipment in experiments involving chemistry, biology, and many other fields. When conducting experiments inside a fume hood, various toxic gases are often generated. If these toxic gases are not properly handled, they can adversely affect the health of laboratory personnel and the laboratory environment.

[0003] Currently, most fume hoods use exhaust fans installed at the top of the hood to remove toxic gases. While this method can remove toxic gases to some extent, it has drawbacks. During routine experiments, the hood door is frequently opened and closed. When the door is opened or closed, some of the toxic gases that were originally extracted by the exhaust fan escape through the windows. This not only introduces toxic components into the laboratory air, polluting the laboratory environment and filling the entire experimental space with odors, affecting the comfort of laboratory personnel, but more importantly, long-term exposure to this contaminated environment can severely damage the health of laboratory personnel, increasing the risk of respiratory diseases, poisoning, and other health problems. Summary of the Invention

[0004] The purpose of this invention is to provide a laboratory fume hood that solves the problem of toxic gases escaping from the window when the fume hood door is opened.

[0005] To solve the above problems, the technical solution of this utility model is as follows:

[0006] A laboratory fume hood includes a cabinet body, a window, a work surface, a liftable door, an air collection hood, and an exhaust pipe. The window is located on the cabinet body panel. The fume hood also includes a first air knife, a base plate, and a front baffle. The first air knife is installed on the inner wall of the cabinet above the window. The base plate is an L-shaped structure formed by bending a head section, a middle section, and a tail section. The middle section is fixedly connected to the work surface by multiple first guide bars. A first gap is formed between the head section and the back panel of the cabinet body, and a second gap is formed between the tail section and the cabinet body panel. The front baffle is fixedly connected to the back panel of the cabinet body by multiple second guide bars. One end of the head section is located in the gap between the front baffle and the back panel of the cabinet body. The air outlet direction of the first air knife is downward.

[0007] Furthermore, a second air knife is installed below the external window of the cabinet, and a rear baffle is provided on one side of the internal panel of the cabinet. A third gap is formed between the rear baffle and the cabinet panel, and the air outlet direction of the second air knife is upward.

[0008] Furthermore, an air guide strip is fixedly connected to the lower end of the lift cabinet door handle.

[0009] Furthermore, the width of the third gap is more than twice that of the first gap.

[0010] Furthermore, the pipes connecting the first and second air knives are both connected to the air pump, and a limit switch is installed on the outer wall of the panel below the window. The limit switch is triggered by the cabinet door and is connected to the air pump.

[0011] Furthermore, one end of the tail section bends towards the back panel of the cabinet.

[0012] Furthermore, one end of the first and second guide bars is triangular.

[0013] The beneficial effects of this utility model are as follows:

[0014] 1. Highly Effective Prevention of Toxic Gas Escape: This invention features a first air knife above the fume hood window. The blown air forms a wall of air at the window, effectively blocking toxic gases from escaping. Combined with a second air knife installed below the window, the air blown from the second air knife flows upwards, working in tandem with the first air knife. Even if a person's arm obstructs some airflow when entering or exiting the window, the escape path of toxic gases from below the arm is completely blocked, providing more reliable protection for the personnel.

[0015] 2. Expanded extraction range: An extraction gap is created between the front baffle and the cabinet back panel. Air blown out by the first air knife enters the second gap, then passes through a specific gap before exiting through the first gap. Utilizing Bernoulli's principle, this reduces the air pressure in the gap between the front baffle and the cabinet back panel, thus creating an extraction gap. This allows toxic gases at the bottom of the cabinet to be extracted, significantly expanding the extraction range of the fume hood. Compared to traditional fume hoods, it can collect toxic gases more comprehensively.

[0016] 3. Intelligent Energy Saving and Noise Reduction: An air pump is connected to the duct connecting the first and second air knives, and controlled by a limit switch below the window. When the cabinet door is closed, the limit switch opens, the air pump stops working, and the first and second air knives stop supplying air, avoiding unnecessary energy consumption and noise generation. When the cabinet door is open, the limit switch closes, the air pump starts, and the first and second air knives begin to work, forming a double air wall, which is both energy-saving and environmentally friendly, and ensures the safety of experimental personnel during operation.

[0017] 4. Optimized airflow guidance: The air guide strip fixedly connected to the upper end of the lift cabinet door handle guides the air blown out by the second air knife smoothly into the third gap, enhancing the blocking effect on toxic gases. At the same time, the bending of the tail section of the bottom plate towards the back panel of the cabinet, as well as the first and second guide strips at one end of the triangle, can effectively guide the airflow, reduce the generation of turbulence, and improve the stability of airflow and ventilation efficiency inside the fume hood. Attached Figure Description

[0018] The present invention will be further described below with reference to the accompanying drawings:

[0019] Figure 1 is a three-dimensional structural diagram of this utility model.

[0020] Figure 2 is a three-dimensional structural diagram of this utility model.

[0021] Figure 3 is a cross-sectional structural diagram of this utility model.

[0022] Figure 4 is a schematic diagram of the electrical structure of this utility model.

[0023] In the diagram: 1. Limit switch; 2. First air knife; 3. Window; 4. Second air knife; 5. Air guide strip; 6. Lifting cabinet door; 7. Exhaust pipe; 8. Air collection hood; 9. Rear baffle; 10. Cabinet body; 11. Second guide strip; 12. Front baffle; 13. Base plate; 14. First guide strip; 15. Workbench surface; 16. First gap; 17. Exhaust gap; 18. Third gap; 19. Second gap. Detailed Implementation

[0024] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0025] As shown in Figures 1 and 2, a laboratory fume hood includes a cabinet body 10, a window 3, a work surface 15, a lift-up cabinet door 6, a collection hood 8, and an exhaust pipe 7. The exhaust pipe 7 is connected to a laboratory ventilation system, which extracts toxic gases from the fume hood. The window 3 is located on the panel of the cabinet body 10. The fume hood also includes a first air knife 2, a base plate 13, and a front baffle 12. The first air knife 2 is installed on the inner wall of the cabinet body 10 above the window 3. The first air knife 2 is connected to an air pump (not shown in the figure) through a pipe. The base plate 13 is an L-shaped structure formed by bending a head section, a middle section and a tail section. The middle section is fixedly connected to the workbench 15 by multiple first guide strips 14. A first gap 16 is separated between the head section and the back panel of the cabinet 10. A second gap 19 is separated between the tail section and the front panel of the cabinet 10. The front baffle 12 is fixedly connected to the back panel of the cabinet 10 by multiple second guide strips 11. One end of the head section is located in the gap between the front baffle 12 and the back panel of the cabinet 10. The air outlet direction of the first air knife 2 is towards the second gap 19.

[0026] During implementation, as shown in Figure 3, the planar air blown out by the first air knife 2 forms an air wall at the window 3, preventing toxic gases inside the cabinet 10 from escaping through the window 3. At the same time, the air blown out by the first air knife 2 enters the second gap 19, passes through the gap between the middle section and the workbench 15, and is blown out from the first gap 16, entering the gap between the front baffle 12 and the back panel of the cabinet 10. Finally, it enters the air collection hood 8 and is extracted from the exhaust pipe 7. Since the air is blown out from the first gap 16 at a relatively high speed, and the first gap 16 is located in the gap between the front baffle 12 and the back panel of the cabinet 10, according to Bernoulli's principle, the air pressure in the gap between the head section and the front baffle 12 will decrease, forming an exhaust gap 17. This allows the toxic gases at the bottom of the cabinet 10 to be extracted, expanding the exhaust range.

[0027] Furthermore, a second air knife 4 is installed below the outer window 3 of the cabinet 10, and a rear baffle 9 is provided on one side of the inner panel of the cabinet 10. A third gap 18 is formed between the rear baffle 9 and the panel of the cabinet 10, and the air outlet direction of the second air knife 4 is the third gap 18. When the experimenter's hand enters or exits the window 3 to perform the experiment, part of the air blown out by the first air knife 2 is blocked by the arm, so there is a possibility that toxic gas may escape from the space below the arm. Therefore, a second air knife 4 blowing upward is set, and the air blowing directions of the first air knife 2 and the second air knife 4 are staggered, so that the air blown out by the second air knife 4 enters the third gap 18 and is discharged from the exhaust pipe 7, thus completely blocking the escape of toxic gas.

[0028] Furthermore, an air guide strip 5 is fixedly connected to the lower end of the handle of the lifting cabinet door 6. The air blown out by the second air knife 4 is guided by the air guide strip 5, allowing it to smoothly enter the third gap 18.

[0029] Furthermore, the width of the third gap 18 is more than twice that of the first gap 16. This structure allows for the collection of air blown out by the first air knife 2 over a larger area, ensuring that the air ejected from the first gap 16 has a sufficient flow rate.

[0030] Furthermore, the pipes connecting the first air knife 2 and the second air knife 4 are both connected to the air pump. A limit switch 1 is installed on the outer wall of the panel below window 3. The limit switch 1 is triggered by the cabinet door 6 and is connected to the air pump. As shown in Figure 4, when the cabinet door 6 is closed, the fume hood is in a closed state, the normally closed limit switch 1SQ is open, the air pump M is de-energized and stops, and the first air knife 2 and the second air knife 4 stop supplying air, so no noise is generated. When the staff opens the cabinet door 6, the limit switch 1SQ closes, the relay KA is energized, and the first air knife 2 and the second air knife 4 start, forming a double air wall to prevent toxic gas from escaping from window 3.

[0031] Furthermore, one end of the tail section bends towards the back panel of the cabinet 10. This structure is used to guide the air blown out by the first air knife 2.

[0032] Furthermore, one end of the first guide bar 14 and the second guide bar 11 is triangular. As shown in Figure 1, only one of the first guide bar 14 and the second guide bar 11 is drawn in the figure. The first guide bar 14 is used to support the middle section of the base plate 13, allowing the middle section to replace the workbench 15. The second guide bar 11 is used to support the front baffle 12. The triangular ends of the first guide bar 14 and the second guide bar 11 face the air blowing side. The triangular ends can guide the air and reduce the generation of turbulence.

[0033] The embodiments described in this specification are merely examples of implementations of the inventive concept. The scope of protection of this utility model should not be considered as limited to the specific forms described in the embodiments. The scope of protection of this utility model also extends to equivalent technical means that can be conceived by those skilled in the art based on the inventive concept.

Claims

1. A laboratory fume hood, comprising a cabinet body, a window, a work surface, a lift-up door, a collection hood, and an exhaust pipe, wherein the window is located on the cabinet body panel, characterized in that: It also includes a first air knife, a base plate, and a front baffle. The first air knife is installed on the inner wall of the cabinet above the window. The base plate is an L-shaped structure formed by bending a head section, a middle section, and a tail section. The middle section is fixedly connected to the workbench by multiple first guide bars. A first gap is separated between the head section and the back panel of the cabinet, and a second gap is separated between the tail section and the front panel of the cabinet. The front baffle is fixedly connected to the back panel of the cabinet by multiple second guide bars. One end of the head section is located in the gap between the front baffle and the back panel of the cabinet. The air outlet direction of the first air knife is downward.

2. A laboratory fume hood according to claim 1, characterized in that: A second air knife is installed below the external window of the cabinet. A rear baffle is provided on one side of the internal panel of the cabinet. A third gap is formed between the rear baffle and the cabinet panel. The air outlet of the second air knife is upward.

3. A laboratory fume hood according to claim 2, characterized in that: An air guide strip is fixedly connected to the lower end of the cabinet door handle.

4. A laboratory fume hood according to claim 2, characterized in that: The width of the third gap is more than twice that of the first gap.

5. A laboratory fume hood according to any one of claims 2 to 4, characterized in that: The pipes connecting the first and second air knives are both connected to the air pump. A limit switch is installed on the outer wall of the panel below the window. The limit switch is triggered by the cabinet door and is connected to the air pump.

6. A laboratory fume hood according to any one of claims 1 to 4, characterized in that: One end of the tail section bends towards the back panel of the cabinet.

7. A laboratory fume hood according to any one of claims 1 to 4, characterized in that: The first and second conductors have a triangular shape at one end.

Images