Biosafety cabinet with controllable exhaust air rate

Abstract

The utility model discloses a biosafety cabinet with controllable exhaust air rate, which comprises a cabinet body and an operation room, the cabinet body is provided with a fan, an air inlet, an air outlet and an exhaust outlet, a circulating air duct is formed on the periphery of the operation room, and the tail end of the circulating air duct is respectively provided with an air supply and exhaust high-efficiency filter. The device is characterized in that the air outlet is communicated with the interior of the circulating air duct through an air exhaust duct, and an air exhaust efficient filter is arranged in the air exhaust duct; an adjusting assembly is arranged on the inner side of the air outlet and comprises a movable plate, a differential pressure sensor and a movable plate controller, the movable plate covers the air outlet, and the movable plate controller adjusts the opening degree of the movable plate relative to the air outlet after collecting the detection value of the differential pressure sensor. The adjusting assembly is arranged at the exhaust outlet, the opening degree of the movable plate is controlled by detecting the pressure difference change, the exhaust air rate is stable, and the use safety is improved.

Description

Technical Field

[0001] The utility model relates to a biological safety cabinet, in particular to a biological safety cabinet with controllable exhaust volume. Background Art

[0002] The biological safety cabinet is designed to protect the operator, the laboratory environment and the experimental materials when operating infectious experimental materials such as primary cultures, bacterial strains and diagnostic specimens, so as to avoid exposure to infectious aerosols and splashes that may be generated during the above operations.

[0003] For the B2 type biosafety cabinet in the secondary biosafety cabinet, an air supply fan is set to continuously supply clean air into the cabinet. After blowing through the working area, the clean air is processed through the circulating air flow channel and then discharged from the exhaust port. Under this structure, the air supply volume of the biosafety cabinet fan becomes one of the important factors affecting the cleanliness of the cabinet. The air supply volume of the fan is in a certain proportion to the exhaust volume. Therefore, in addition to the air supply capacity of the fan itself, the stability of the exhaust volume is also one of the parameters that affect the cleanliness of the cabinet. Summary of the invention

[0004] The utility model aims to provide a biosafety cabinet with controllable exhaust volume. Through structural improvement, the exhaust volume can be controlled, thereby stabilizing the supply volume of clean air in the cabinet and ensuring the safety of the biosafety cabinet.

[0005] To achieve the above-mentioned purpose, the technical solution adopted by the utility model is: a biological safety cabinet with controllable exhaust volume, comprising a cabinet body and an operating room, the cabinet body is provided with a fan, an air inlet, an air outlet and an exhaust outlet, and a circulating air duct is formed outside the operating room, and the ends of the circulating air duct are respectively provided with supply and exhaust high-efficiency filters, the exhaust outlet is connected with the circulating air duct through the exhaust air duct, and the exhaust air duct is provided with an exhaust high-efficiency filter; an adjustment component is provided on the inner side of the exhaust outlet, and the adjustment component includes a movable plate, a pressure difference sensor and a movable plate controller, the movable plate covers the exhaust outlet, and the movable plate controller adjusts the opening of the movable plate relative to the exhaust outlet after collecting the detection value of the pressure difference sensor.

[0006] In the above technical solution, the movable plate controller includes a control motor and a driving connecting rod, one end of the driving connecting rod is connected to the control motor, and the other end is connected to the movable plate. The moving distance of the driving connecting rod is controlled by the forward and reverse rotation of the control motor. The movable plate adjusts the distance between it and the inner wall of the exhaust port through the movement of the driving connecting rod.

[0007] In the above technical solution, a rack is provided at the connecting end of the driving connecting rod and the control motor, and a gear is sleeved at the output end of the control motor, and the gear is meshingly connected with the rack.

[0008] Another technical solution is that the movable plate controller includes a hydraulic cylinder, and the front end of the piston rod of the hydraulic cylinder is connected to the movable plate.

[0009] In the above technical solution, the pressure difference sensor is arranged between the exhaust high-efficiency filter and the movable plate, and the movable plate controller receives the pressure difference value of the pressure difference sensor. When the pressure difference value is less than the set value, the movable plate is driven to contract to increase the opening of the exhaust port. Otherwise, the movable plate is driven to expand to reduce the opening of the exhaust port.

[0010] In the above technical solution, the adjustment component includes a shell, which is installed on the inner side of the exhaust port. An opening is provided on the bottom plate of the shell, which corresponds to the exhaust port. The movable plate separates the exhaust port and the opening, and the movable plate controller is arranged on the bottom plate of the shell.

[0011] Due to the application of the above technical solution, the utility model has the following advantages compared with the prior art:

[0012] 1. In the utility model, an adjustment component is provided, including a movable plate, a pressure difference sensor and a movable plate controller. The pressure difference under the movable plate is detected by the pressure difference sensor, and compared with the pressure difference value of the exhaust port under normal wind speed (pre-recorded in the movable plate controller, that is, the pressure difference value measured when the supply air speed and exhaust air speed of the biological safety cabinet are adjusted to the standard value). When the exhaust flow rate changes and causes the pressure difference to change, the movable plate controller can control the opening size of the movable plate, thereby adjusting the exhaust volume, restoring the pressure difference to the standard state, ensuring the stability of the exhaust volume (that is, stabilizing the inward air supply volume of the high-efficiency filter), and improving the safety of the biological safety cabinet.

[0013] 2. The utility model has a simple structure, and can detect and adjust in real time, which is easy to implement. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a structural schematic diagram of the first embodiment of the utility model;

[0015] Figure 2 It is a structural schematic diagram of the adjustment component in the first embodiment of the utility model.

[0016] Among them: 1. Cabinet; 2. Operation room; 3. Air inlet; 4. Exhaust outlet; 5. Fan; 6. Supply air high-efficiency filter; 7. Exhaust air high-efficiency filter; 8. Adjustment component; 9. Movable plate; 10. Pressure difference sensor; 11. Shell; 12. Control motor; 13. Drive connecting rod; 14. Circulation air duct; 15. Exhaust air duct. DETAILED DESCRIPTION

[0017] The utility model is further described below in conjunction with the accompanying drawings and embodiments:

[0018] Example 1: Refer to Figures 1-2 As shown, a biosafety cabinet with controllable exhaust air volume includes a cabinet body 1 and an operation chamber 2. A blower 5, an air inlet 3, an air outlet, and an exhaust outlet 4 are provided on the cabinet body 1. A circulating air duct is formed around the operation chamber 2. The ends of the circulating air duct 14 are respectively provided with a supply high-efficiency filter 6 and an exhaust high-efficiency filter 7. An adjustment assembly 8 is provided inside the exhaust outlet 4. The adjustment assembly 8 includes a movable plate 9, a differential pressure sensor 10, and a movable plate controller. The movable plate 9 covers the exhaust outlet 4. After the movable plate controller collects the detection value of the differential pressure sensor 10, it adjusts the opening degree of the movable plate 9 relative to the exhaust outlet 4.

[0019] In this embodiment, the differential pressure sensor 10 detects the differential pressure value a at the exhaust outlet 4 and compares it with the differential pressure value A under the standard state pre-stored in the control system. If the differential pressure value a < A, it means that the exhaust air volume has become smaller and the opening degree of the exhaust outlet needs to be increased. At this time, the movable plate controller drives the movable plate 9 to open, increasing the exhaust air volume and restoring the differential pressure value to the normal value. On the contrary, if the differential pressure value a > A, it means that the exhaust air volume is large and the opening degree of the exhaust outlet needs to be reduced. At this time, the movable plate controller drives the movable plate 9 to reduce the opening degree, realizing a decrease in the exhaust area and restoring the differential pressure value to the standard value A. Thus, the constant supply air volume into the high-efficiency filter 6 is ensured, and the safety of the biosafety cabinet is guaranteed.

[0020] As Figure 1 shown, the adjustment assembly 8 includes a housing 11. The housing 11 is installed inside the exhaust outlet 4. An opening is provided on the bottom plate of the housing, and this opening corresponds to the exhaust outlet 4. The movable plate 9 separates the exhaust outlet 4 and the opening. The movable plate controller is arranged on the bottom plate of the housing.

[0021] Another implementation method: The adjustment assembly includes a movable grille plate, a fixed grille plate, a differential pressure sensor, and a movable grille plate controller. The movable grille plate and the fixed grille plate cover the exhaust outlet. The fixed grille plate is fixed on the box body (inner wall of the cabinet) of the exhaust outlet. The movable grille plate is relatively limited above the fixed grille plate and is displaced relative to the fixed grille plate. In this implementation method, the fixed grille plate is used as the mounting plate for the movable grille plate controller in the adjustment assembly.

[0022] The differential pressure sensor 10 is arranged between the exhaust high-efficiency filter 7 and the movable plate 9. The movable plate controller receives the differential pressure value of the differential pressure sensor 10. When the differential pressure value is less than the set value, it drives the movable plate 9 to contract, increasing the opening degree of the exhaust outlet 4. Otherwise, it drives the movable plate 9 to expand, reducing the opening degree of the exhaust outlet 4.

[0023] As Figure 2As shown, the movable plate controller includes a control motor 12 and a driving connecting rod 13, one end of the driving connecting rod 13 is connected to the control motor 12, and the other end is connected to the movable plate 9. The moving distance of the driving connecting rod 13 is controlled by the forward and reverse rotation of the control motor 12. The movable plate 9 adjusts the distance between it and the inner wall of the exhaust port 4 (that is, adjusts the size of the opening on the bottom plate of the shell) through the movement of the driving connecting rod 13.

[0024] Specifically, a rack is provided at the connection end of the driving connecting rod 13 and the control motor, a gear is provided at the output end of the control motor, and the gear is meshed with the rack. The forward and reverse rotation of the control motor and the cooperation of the gear on the control motor shaft and the rack push or pull the movable plate to adjust the exhaust area.

[0025] In addition, the micro cylinder in the prior art can also be used to achieve the above, and the movable plate controller includes a hydraulic cylinder, and the front end of the piston rod of the hydraulic cylinder is connected to the movable plate. The movable plate is pushed out or pulled back by the extension and contraction of the piston rod to achieve the change of the unfolded area of ​​the movable plate.

Claims

1. A biosafety cabinet with controllable exhaust volume, comprising a cabinet body and an operating room, wherein the cabinet body is provided with a fan, an air inlet, an air outlet and an exhaust port, and a circulating air duct is formed outside the operating room, and the ends of the circulating air duct are respectively provided with supply and exhaust high-efficiency filters, characterized in that: The exhaust port is connected to the circulating air duct through an exhaust duct, and an exhaust high-efficiency filter is provided in the exhaust duct; an adjustment component is provided on the inner side of the exhaust port, and the adjustment component includes a movable plate, a pressure difference sensor and a movable plate controller, and the movable plate covers the exhaust port. After the movable plate controller collects the detection value of the pressure difference sensor, it adjusts the opening of the movable plate relative to the exhaust port.

2. The biosafety cabinet with controllable exhaust volume according to claim 1, characterized in that: The movable plate controller includes a control motor and a driving connecting rod, one end of the driving connecting rod is connected to the control motor, and the other end is connected to the movable plate. The moving distance of the driving connecting rod is controlled by the forward and reverse rotation of the control motor. The movable plate adjusts the distance between it and the inner wall of the exhaust port through the movement of the driving connecting rod.

3. The biosafety cabinet with controllable exhaust volume according to claim 2, characterized in that: A rack is provided at the connecting end of the driving connecting rod and the control motor, and a gear is sleeved at the output end of the control motor. The gear is meshed and connected with the rack.

4. The biosafety cabinet with controllable exhaust volume according to claim 1, characterized in that: The movable plate controller comprises a hydraulic cylinder, and the front end of the piston rod of the hydraulic cylinder is connected to the movable plate.

5. The biosafety cabinet with controllable exhaust volume according to claim 1, characterized in that: The pressure difference sensor is arranged between the exhaust high-efficiency filter and the movable plate. The movable plate controller receives the pressure difference value of the pressure difference sensor. When the pressure difference value is less than the set value, the movable plate is driven to contract to increase the opening of the exhaust port. Otherwise, the movable plate is driven to expand to reduce the opening of the exhaust port.

6. The biosafety cabinet with controllable exhaust volume according to claim 1, characterized in that: The adjustment component includes a shell, which is installed on the inner side of the exhaust port. An opening is provided on the bottom plate of the shell, which corresponds to the exhaust port. The movable plate separates the exhaust port and the opening. The movable plate controller is arranged on the bottom plate of the shell.

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