Air pressure adjusting system for clean delivery window

Abstract

The utility model discloses a clean delivery window air pressure regulating system which comprises a box body, a main fan, a high-efficiency air filter and a purification cavity, the purification cavity is located at the rear end of the high-efficiency air filter, and the box body wraps the corresponding purification cavity and a static pressure box body formed by the main fan and the high-efficiency air filter in a sealed mode. The high-efficiency air filter is characterized in that an auxiliary fan is arranged on the side wall of the static pressure box body at the front end of the high-efficiency air filter, a valve is arranged at an air outlet of the auxiliary fan, and a valve opening and closing signal is connected with a trigger switch of a driving signal of the auxiliary fan. Opening and closing of the trigger switch are associated with opening and closing of the door body. According to the utility model, the auxiliary fan and the valve are arranged, so that the supplement of lost airflow in the purification cavity is realized, the interference of external airflow on the internal environment of a clean area due to differential pressure gradient after the delivery window door body is opened is avoided, and the cleanliness of the clean area is ensured when articles are delivered.

Description

Technical Field

[0001] This utility model relates to a cleanroom equipment technology, and more particularly to a cleanroom transfer window air pressure regulation system. Background Technology

[0002] A pass-through cabinet is a key piece of equipment in a cleanroom system for the two-way transfer of materials. Through a double-door interlocking mechanism, air filtration system, and differential pressure control, it enables the safe transfer of items between clean and non-clean areas, preventing cross-contamination. With a built-in HEPA / ULPA high-efficiency filter and fan airflow circulation system, the interior of the cabinet is at zero pressure when the door is closed, achieving a self-cleaning effect.

[0003] Pass-through windows have a wide range of applications, including:

[0004]

[0005] In existing technology, when either side of the door is opened, a pressure gradient is created between the inside of the transfer window and the external environment, leading to the following chain reaction:

[0006] 1. Sudden pressure drop: The positive pressure value inside the cavity can drop at a rate of 30-50 Pa / second (with the door fully open).

[0007] 2. Air backflow: External unclean air enters the cavity through the door gaps in a vortex (increasing the concentration of pollutant particles by 5-10 times).

[0008] 3. Deterioration of cleanliness: The number of particles larger than 0.5μm may exceed the standard, which violates the cleanliness requirements described in ISO 14644-1.

[0009] The potential impacts and consequences of the above changes:

[0010] ● Biological laboratories: Increase the risk of cross-contamination of samples;

[0011] ● Electronics workshop: Dust buildup can cause short circuits in chip circuits;

[0012] ●Medical scenario: Aerosol diffusion can cause distortion of test results.

[0013] 4. When the door is closed quickly and forcefully, the short-term pressure gradient inside the cavity may cause the door to fail to close or leak through the gaps in the opposite side of the door, introducing unclean air into the clean area.

[0014] 5. If a clean pass-through window is installed in the passageway of a negative pressure biological cleanroom, unclean aerosols in the negative pressure biological zone may spread through the pass-through window or disrupt the pressure gradient of the negative pressure zone, causing the spread of biological contamination.

[0015] Therefore, researchers in this field need to improve existing technologies as soon as possible to provide users with better products and enhance their safety. Summary of the Invention

[0016] The purpose of this invention is to provide a clean transfer window air pressure regulation system. Through structural improvements, it ensures stable air pressure inside the transfer window, avoids external interference with the cleanliness of the inner cavity, reduces the risk of cross-contamination, and improves safety in use.

[0017] To achieve the above objectives, the technical solution adopted by this utility model is as follows: a cleanroom transfer window air pressure regulation system, comprising a housing, a main fan, a high-efficiency air filter, and a purification chamber. The purification chamber is located at the rear end of the high-efficiency air filter. The housing encloses the corresponding purification chamber and the static pressure chamber formed by the main fan and the high-efficiency air filter. Doors are provided on both sides of the housing. An auxiliary fan is provided on the side wall of the static pressure chamber at the front end of the high-efficiency air filter. A valve is provided at the air outlet of the auxiliary fan. The valve opening and closing signal is connected to a trigger switch of the drive signal of the auxiliary fan. The opening and closing of the trigger switch is related to the opening and closing of the doors.

[0018] In the above technical solution, the trigger switch includes several electromagnetic triggers, which are respectively set on the doors on both sides of the housing. When the door is opened, the electromagnetic triggers are disconnected, and the drive circuit of the valve and the auxiliary fan is connected; conversely, when the door is closed, the electromagnetic triggers are closed, and the drive circuit of the valve and the auxiliary fan is interlocked and closed.

[0019] In the above technical solution, the trigger switch is further provided with a timer, which is connected in series in the drive circuit of the valve and the auxiliary fan. The timer is preset with a turn-off delay parameter T value.

[0020] Another technical solution is that the trigger switch includes a differential pressure sensor, which is installed in the purification chamber and has a preset air pressure value S. When the detected air pressure is lower than the preset air pressure value S, the trigger switch closes and the valve and auxiliary fan start; when the detected air pressure returns to the preset air pressure value S, the trigger switch opens and the valve and auxiliary fan close.

[0021] A further technical solution is that the air pressure value includes several interval values, and the valve is a controllable swing valve with a plurality of opening positions set within it. Each opening position corresponds to one of the interval values, and the controller for each opening position is connected to the differential pressure sensor. The opening position controller has a built-in differential pressure signal calculation circuit, which calculates the opening stroke of the valve based on the comparison between the measured differential pressure value and the set value.

[0022] In the above technical solution, the valve includes a sliding cover plate, which moves along the air outlet of the auxiliary fan via a transmission mechanism. When the sliding cover plate is closed, it isolates the auxiliary fan from the front static pressure box. When the sliding cover plate is open, the auxiliary fan sends supplementary airflow into the front static pressure box through the suction port. The suction port is located on the box body and communicates with the outside.

[0023] In the above technical solution, the side wall of the box and the purification chamber form a circulating air duct. A return air port connected to the circulating air duct is provided on the cavity wall near the bottom of the purification chamber. The circulating air duct connects the return air port and the air inlet of the main fan to form a self-cleaning circulation system.

[0024] Due to the application of the above technical solution, this utility model has the following advantages compared with the prior art:

[0025] 1. An auxiliary fan is provided in this utility model. When the transfer window is opened, due to the instantaneous airflow disturbance, the outside air can easily enter the purification chamber. At this time, the auxiliary fan is activated to supplement the purification chamber with clean airflow, so that the air pressure inside the purification chamber is greater than the outside air pressure, so that the airflow can only flow from the inside to the outside, thereby ensuring that the clean environment inside the chamber is not disturbed and ensuring the cleanliness of the items in the transfer window.

[0026] 2. A valve is installed at the air outlet of the auxiliary fan. Both are controlled to open and close by a trigger switch. The trigger switch includes an electromagnetic trigger. The opening and closing of the door is linked to the electromagnetic trigger. When the door is opened, the auxiliary fan and valve are opened to supplement the airflow to the purification chamber. When the door is closed, the auxiliary fan and valve are closed, and the main fan delivers air normally.

[0027] 3. An air pressure sensor is installed inside the purification chamber to detect the air pressure in the working area. When the door is opened, the air pressure drops, and the air pressure sensor sends a signal to the controllable swing valve controller to open the auxiliary fan and valve to supplement the working area with clean airflow. The valve opening is adjusted according to the air pressure drop, indirectly regulating the air intake to ensure a positive pressure state inside the purification chamber (working area). This forms an air curtain at the boundary between the inside and the outside, preventing external contamination of the purified items in the working area and protecting the inside from interference.

[0028] 4. A return air vent is installed inside the purification chamber, and a circulating air duct is installed on the inner wall of the chamber. The circulating air duct connects the return air vent and the air inlet of the main fan to form a self-cleaning circulation system for airflow. Attached Figure Description

[0029] Figure 1 This is a structural schematic diagram of an embodiment of the present utility model;

[0030] Figure 2 This is a schematic diagram of the airflow direction when one side of the door is open in an embodiment of this utility model;

[0031] Figure 3 This is a schematic diagram of the structure with a differential pressure sensor in an embodiment of this utility model.

[0032] The components include: 1. Housing; 2. Main fan; 3. High-efficiency air filter; 4. Purification chamber; 5. Door; 6. Front static pressure box; 7. Auxiliary fan; 8. Valve; 9. Inlet; 10. Circulating air duct; 11. Return air outlet; 12. Air inlet; 13. Differential pressure sensor; 14. Electromagnetic trigger. Detailed Implementation

[0033] The following description is merely a preferred embodiment of the present invention and is not intended to limit the scope of the present invention. Furthermore, the terms "vertical," "horizontal," "top," "bottom," "front," "rear," "upper," "lower," "inner," and "outer" used in the embodiments of the present invention indicate orientation or positional relationships based on the appendix. Figure 1 The orientations or positional relationships shown, or the orientations or positional relationships in which the product is usually placed during use, are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. The following will refer to the appendix... Figure 1-3 The present invention will be described in detail with reference to the embodiments.

[0034] Example:

[0035] A cleanroom pass-through window air pressure regulation system includes a housing 1, a main fan 2, a high-efficiency air filter 3, and a purification chamber 4. The purification chamber 4 is located at the rear end of the high-efficiency air filter 3. The housing encloses the purification chamber 4 and the static pressure chamber 6 formed by the main fan 2 and the high-efficiency air filter 3. Doors 5 are provided on both sides of the housing 1. An auxiliary fan 7 is provided on the side wall of the static pressure chamber 6 at the front end of the high-efficiency air filter 3. A valve 8 is provided at the air outlet of the auxiliary fan 7. The opening and closing signal of the valve 8 is connected to a trigger switch via the drive end of the auxiliary fan 7. The opening and closing of the trigger switch is correlated with the opening and closing of the doors 5. Here, "correlated" means that the two are linked; the opening and closing of the trigger switch is triggered by the opening and closing of the doors 5.

[0036] In this embodiment, the trigger switch includes several electromagnetic triggers 14, which are respectively disposed on the doors 5 on both sides of the purification chamber 4. When the door 5 is opened, the electromagnetic triggers 14 are deactivated, and the drive circuit of the valve 8 and the auxiliary fan 7 is connected. Conversely, when the door 5 is closed, the electromagnetic triggers 14 are closed, and the drive circuit of the valve 8 and the auxiliary fan 7 is interlocked and shut off. Because the opening of the door 5 causes a drop in air pressure in the purification chamber 4 (operating area), external airflow can easily enter the operating area, thereby affecting the cleanliness of the items. Therefore, at the moment the door 5 is opened, the electromagnetic triggers 14 are deactivated, the drive circuit is connected, the valve 8 is opened, and the auxiliary fan 7 is started, bringing supplementary air into the front static pressure box 6. The airflow blown out by the main fan 2 is filtered by the high-efficiency air filter 3 and then enters the operating area, increasing the air pressure in the operating area. This increases the air pressure in the operating area to a level higher than the external air pressure (outside the door 5), forming a shielding effect and blocking the intrusion of external airflow.

[0037] In one implementation, the trigger switch also includes a timer connected in series in the drive circuit of valve 8 and auxiliary fan 7. The timer is preset with a shutdown delay parameter T. After door 5 is closed, to ensure stable air pressure, valve 8 and auxiliary fan 7 can be closed after a delay of T.

[0038] Another embodiment is, as Figure 3 As shown, the trigger switch includes a differential pressure sensor 13, which is installed inside the purification chamber 4. A preset air pressure value S is set. When the detected air pressure is lower than the preset air pressure value S, the trigger switch closes, and the valve 8 and the auxiliary fan 7 start. When the detected air pressure returns to the preset air pressure value S, the trigger switch opens, and the valve 8 and the auxiliary fan 7 close.

[0039] Furthermore, several air pressure range values ​​can be set. The valve 8 is a controllable swing valve with multiple opening positions, each corresponding to one of the aforementioned range values, such as A = [0,5]; B = [6,10]... The above data is set according to actual usage. The controller for the opening position is connected to the differential pressure sensor 13. Through the internal calculation circuit of the differential pressure sensor 13, the valve's opening stroke is driven by comparing the measured differential pressure value with the set value, thereby adjusting the opening position of the controllable swing valve and controlling the air intake of the auxiliary fan 7, ensuring the stability of the air pressure in the working area. The opening position controller has a built-in differential pressure signal calculation circuit.

[0040] The valve 8 includes a sliding cover plate, which slides along the outlet of the auxiliary fan 7 via a transmission mechanism. The transmission mechanism can be an electro-pneumatic or hydraulic jack, or other power transmission devices in the prior art. When the sliding cover plate is closed, it isolates the auxiliary fan 7 from the front static pressure box 6. When the sliding cover plate is open, the auxiliary fan 7 delivers supplementary airflow into the front static pressure box 6 through the suction port 9, which is located on the box body 1 and communicates with the outside.

[0041] The side wall of the housing 1 and the purification chamber form a circulating air duct 10. A return air inlet 11 connected to the circulating air duct 10 is provided on the cavity wall near the bottom of the purification chamber 4. The circulating air duct 10 connects the return air inlet 11 with the air inlet 12 of the main fan to form a self-cleaning circulation system.

[0042] The specific working process of the self-cleaning circulation system is as follows:

[0043] When both doors 5 of the pass-through window are closed, the main fan 2 starts, while the auxiliary fan 7 shuts down. The controllable swing valve rises to the top, isolating the auxiliary fan 7 from the internal airflow channel. At this time, the internal space forms a sealed space. The main fan 2 delivers the internal air to the internal operating area after filtering it through the high-efficiency air filter 3, thereby purifying the surfaces of items in the work area. The polluted air passing over the surfaces of the items is then returned to the air inlet 12 of the main fan 2 via the return air vent 11, thus forming a self-cleaning circulation system.

[0044] When one of the doors 5 of the pass-through window is open, the main fan 2 operates, the controllable swing valve descends, and the auxiliary fan 8 operates simultaneously, forming an integrated airflow channel. It draws outside air through the intake 9 into the static pressure box 6 at the front end of the high-efficiency air filter 3. At this time, the main fan 2 and the auxiliary fan 7 together filter the air through the high-efficiency air filter 3 and deliver it to the internal working area. Because the auxiliary fan 7 delivers more outside air into the pass-through window, the pressure in the working area is greater than the external pressure on the open side of door 5. This forces airflow to flow only from the pass-through window to the outside, creating an air curtain at the boundary between the pass-through window and the outside. This prevents external contamination of the purified items in the working area, protecting the interior from interference.

[0045] Although embodiments of the present invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A cleanroom pass-through window air pressure regulation system, comprising a housing, a main fan, a high-efficiency air filter, and a purification chamber, wherein the purification chamber is located at the rear end of the high-efficiency air filter, the housing encloses and encloses the corresponding purification chamber and the static pressure chamber formed by the main fan and the high-efficiency air filter, and doors are respectively provided on both sides of the housing, characterized in that: An auxiliary fan is provided on the side wall of the front static pressure box of the high-efficiency air filter. A valve is provided at the air outlet of the auxiliary fan. The valve opening and closing signal is connected to the trigger switch of the drive signal of the auxiliary fan. The opening and closing of the trigger switch is related to the opening and closing of the door.

2. The cleanroom pass-through window air pressure regulation system according to claim 1, characterized in that: The trigger switch includes several electromagnetic triggers, which are respectively installed on the doors on both sides of the housing. When the door is opened, the electromagnetic triggers are disconnected, and the drive circuit of the valve and the auxiliary fan is connected; conversely, when the door is closed, the electromagnetic triggers are closed, and the drive circuit of the valve and the auxiliary fan is interlocked and shut off.

3. The cleanroom pass-through window air pressure regulation system according to claim 2, characterized in that: The trigger switch is also equipped with a timer, which is connected in series in the drive circuit of the valve and the auxiliary fan. The timer is preset with a turn-off delay parameter T value.

4. The cleanroom pass-through window air pressure regulation system according to claim 1, characterized in that: The trigger switch includes a differential pressure sensor, which is installed inside the purification chamber. A preset air pressure value S is set. When the detected air pressure is lower than the preset air pressure value S, the trigger switch closes, and the valve and auxiliary fan start. When the detected air pressure returns to the preset air pressure value S, the trigger switch opens, and the valve and auxiliary fan close.

5. The cleanroom pass-through window air pressure regulation system according to claim 4, characterized in that: The air pressure value includes several interval values. The valve is a controllable swing valve with multiple opening positions set inside. Each opening position corresponds to one of the interval values. The controller of the opening position is connected to the differential pressure sensor. The opening position controller has a built-in differential pressure signal calculation circuit. It calculates the opening stroke of the valve based on the comparison between the measured value of the differential pressure and the set value.

6. The cleanroom pass-through window air pressure regulation system according to claim 1 or 4, characterized in that: The valve includes a sliding cover plate, which moves along the outlet of the auxiliary fan via a transmission mechanism. When the sliding cover plate is closed, it isolates the auxiliary fan from the front static pressure box. When the sliding cover plate is open, the auxiliary fan sends supplementary airflow into the front static pressure box through the suction port, which is located on the box body and communicates with the outside.

7. The cleanroom pass-through window air pressure regulation system according to claim 1, characterized in that: The side wall of the housing and the purification chamber form an internal circulating air duct. A return air inlet connected to the circulating air duct is provided on the cavity wall near the bottom of the purification chamber. The circulating air duct connects the return air inlet to the air inlet of the main fan, forming a self-cleaning circulation system.

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