A micro differential pressure air volume testing device

Abstract

The utility model discloses a kind of micro pressure difference air volume testing devices, it is related to micro pressure detection, including the detection end of hot ball anemometer and operation terminal, including rounded rectangular wind scooper and the cylinder body communicated with it;The loading platform is slidably arranged in the cylinder body, and the detection end is fixedly installed in the side of the loading platform towards the rounded rectangular wind scooper and is centrally distributed.This utility model is simple in structure, convenient to operate, by staying and collecting to the preset collection point, then the data difference of the multiple data groups obtained, so as to judge whether the test result is real.

Description

Technical Field

[0001] This utility model relates to micro-pressure detection, specifically a micro-pressure differential airflow testing device. Background Technology

[0002] A hot-wire anemometer is a precision instrument specifically designed to measure low wind speeds or minute airflows. Its core advantage lies in its high sensitivity and rapid response to minute air volumes. It primarily measures the heat dissipation effect of an electrically heated sensing element. Because there is a clear relationship between the cooling effect of the fluid on the hot-wire and the flow velocity under low wind speed conditions, it can extremely accurately capture minute airflows that are difficult for traditional mechanical anemometers to detect.

[0003] Referring to the expired Chinese patent, publication number CN202886399U, published on 2013-04-17, a hot-wire anemometer was disclosed.

[0004] The current technical shortcomings of hot-wire anemometers lie in the fact that their sensing end is completely exposed to the external environment. Especially when measuring airflow inside air ducts or at exhaust windows in cleanrooms, the sensor is easily affected by irrelevant external airflow, making it difficult to stably and accurately capture the weak airflow within the confined channel. Utility Model Content

[0005] The purpose of this invention is to provide a micro-differential pressure airflow testing device to address the aforementioned shortcomings in the prior art.

[0006] To achieve the above objectives, this utility model provides the following technical solution: a micro-pressure differential air volume testing device, including a detection end of a hot-wire anemometer and an operation terminal, including a rounded rectangular air guide shroud and a cylinder connected thereto; A platform is slidably disposed inside the cylinder, and the detection end is fixedly installed on the side of the platform facing the rounded rectangular air guide and is centered thereon.

[0007] Preferably, the platform has a first annular groove, and a transparent acrylic plate is fixedly installed in the first annular groove.

[0008] Preferably, the platform has a second annular groove, and a breathable mesh is fixedly installed in the second annular groove. The outer circumferential radius of the second annular groove is smaller than the inner circumferential radius of the first annular groove.

[0009] Preferably, a cross-shaped reinforcing rib is fixedly installed on one side of the platform.

[0010] Preferably, the port of the rounded rectangular air guide shroud is provided with a soft rubber pad.

[0011] Preferably, the rounded rectangular air guide shroud is frustum-shaped, and its narrow opening is connected to the cylindrical body.

[0012] Preferably, an adapter is fixedly provided on the inner wall of the port at one end of the cylinder opposite to the rounded rectangular air guide cover, and the adapter is rotatably connected to the operating terminal.

[0013] Preferably, the port of the cylinder is fixedly provided with a fixed cylinder extending inward, and the outer wall of the fixed cylinder is slidably provided with a movable cylinder. The number of movable cylinders is several, and they are nested together and slidably connected. The platform is fixedly installed on the port of the last-stage moving cylinder. In the above technical solution, the micro-pressure difference air volume testing device provided by this utility model has the following beneficial effects: a rounded rectangular air guide cover is used to cover the air duct or exhaust window to form a relatively sealed area. Then, by pushing the platform, the detection end is gradually brought closer to the air duct or exhaust window. During the process, the device stops and collects data at the preset collection point. Then, the difference between the data of multiple sets of data is compared to determine whether the test result is true. Attached Figure Description

[0014] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this utility model. For those skilled in the art, other drawings can be obtained based on these drawings.

[0015] Figure 1 A schematic diagram of the overall structure provided for an embodiment of this utility model; Figure 2 A structural schematic diagram provided for an embodiment of this utility model; Figure 3 A schematic diagram of the structure of the rounded rectangular air guide shroud provided in the embodiment of this utility model; Figure 4 A schematic diagram of the operating terminal and adapter provided in an embodiment of this utility model.

[0016] Explanation of reference numerals in the attached figures: 1. Rounded rectangular air guide cover; 11. Soft rubber pad; 2. Cylinder body; 21. Adapter seat; 22. Fixed cylinder; 23. Moving cylinder; 3. Platform; 33. Cross-shaped reinforcing rib; 4. Transparent acrylic sheet; 5. Breathable mesh; 100. Detection end; 101. Operation terminal. Detailed Implementation

[0017] To enable those skilled in the art to better understand the technical solution of this utility model, the present utility model will be further described in detail below with reference to the accompanying drawings.

[0018] Please see Figure 1-4 This utility model provides a technical solution: a micro-pressure difference air volume testing device, including a rounded rectangular air guide hood 1, a cylinder 2 connected thereto, a platform 3 slidably disposed inside the cylinder 2, and a hot-wire anemometer detection end 100 and its operation terminal 101 as the core measuring element.

[0019] Furthermore, the aforementioned rounded rectangular air guide shroud 1 is preferably a frustum-shaped structure, with its large-diameter end designed to cover the air duct opening or exhaust window to be tested. A soft rubber pad 11 is fixedly installed around the edge of this port, its function being to create a relatively sealed measurement environment when the air guide shroud 1 is in close contact with the surface being measured, effectively isolating interference from external stray airflow. The small-diameter end of the air guide shroud 1 is fixedly connected to the cylinder 2.

[0020] The cylinder 2 is the main body supporting the sliding mechanism. An adapter 21 is fixedly installed on the inner wall of the end of the cylinder 2 furthest from the air guide shroud 1. This adapter 21 is rotatably connected to the operating terminal 101 (typically a display and control unit) of the hot-wire anemometer, for example, via a ball joint or bearing. This allows the operator to flexibly adjust the angle of the operating terminal 101, facilitating the observation of readings and the acquisition of operational data, without altering the sealing posture of the air guide shroud 1.

[0021] To achieve smooth advancement and precise positioning of the detection end 100, a fixed cylinder 22 extending inward is fixedly installed at the port of the cylinder 2. At least one movable cylinder 23 is slidably sleeved on the outer wall of the fixed cylinder 22. In this embodiment, there are several movable cylinders 23, which are nested together and connected in a multi-stage telescopic sliding manner, similar in structure to a telescopic antenna or a pull rod. The platform 3 is fixedly installed on the port of the innermost (i.e., the last stage) movable cylinder 23. To ensure that the sliding components do not slip off each other during operation, limit stops (such as retaining rings or flanges) are provided at both ends of all movable cylinders 23 and at the corresponding ends of the fixed cylinder 22.

[0022] Secondly, the stage 3 is used to fix and mount the detection end 100 of the hot-wire anemometer. The detection end 100 is installed on the side of the stage 3 facing the rounded rectangular air guide shroud 1 and is strictly centered to ensure that the airflow is directly in front of the sensor's sensitive element during measurement, thus ensuring the accuracy of the data.

[0023] To further optimize the measurement environment, a first annular groove and a second annular groove are formed on the stage 3. The second annular groove is located on the inner side, and a breathable mesh 5 is fixedly installed inside it. This mesh can regulate the airflow passing through the detection end 100, making it more uniform and stable, and reducing the impact of turbulence on instantaneous readings. The first annular groove is located on the outer periphery of the second annular groove, and a transparent acrylic plate 4 is fixedly installed inside it. This acrylic plate 4 can protect the internal detection end 100 and the breathable mesh 5 from accidental contact, and its transparency allows the operator to observe the internal situation without affecting the airflow.

[0024] To enhance the structural strength of the platform 3 and prevent it from deforming under stress during long-term use, a cross-shaped reinforcing rib 33 is fixedly installed on the side of the platform 3 facing away from the detection end 100.

[0025] Working principle: First, the rounded rectangular air guide shroud 1 is tightly attached to the air duct or exhaust window to be tested through the soft rubber pad 11 at its port, forming a temporary, relatively closed measurement chamber.

[0026] Then, the operator slowly pushes the operating terminal 101, driving the platform 3 and its detection end 100 closer to the air duct opening through the extension and retraction of the multi-stage moving cylinder 23. During this advancement, the system will briefly stop at multiple preset collection points to collect wind speed data.

[0027] Judgment method: Calculate the data difference (gradient): Record the wind speed values ​​at several consecutive collection points (e.g., point A, point B, point C) and calculate the data difference (i.e., gradient) between adjacent points, such as difference 1 = Vb - Va, difference 2 = Vc - Vb. Check whether these consecutive data differences maintain a consistent growth trend (or conform to the expected trend of the physical model), and whether their fluctuation range is within a preset reasonable threshold. If the data sequence is smooth and the gradient change is continuous and stable, it indicates that the measurement environment is less affected by interference, and the measured wind speed curve is true and reliable. The stable values ​​of the last few points or the fitted value of the entire curve can be taken as the final wind volume calculation result.

[0028] If the data difference fluctuates drastically (e.g., suddenly increases, decreases, or even becomes negative), it indicates that the measurement may have been affected by instantaneous external airflow interference, device seal failure, or the measuring point being located in a turbulent region. The test results for this set are "inaccurate" and the seal needs to be checked again or the measurement needs to be repeated.

[0029] Assuming the detection point starts 10cm from the air duct opening and collects data every 2cm, for a total of 5 points, the ideal data and actual abnormal data are compared as follows: Judgment of ideal data: The gradients are calculated as follows: (0.65-0.50)=0.15, (0.82-0.65)=0.17, (1.00-0.82)=0.18, (1.20-1.00)=0.20. The gradient values ​​stabilize between 0.15 and 0.20, showing a continuous and stable growth trend. This indicates that the measurement environment is good and the test results are accurate and valid. The final air volume can be taken as the average of points 4 and 5, or it can be estimated using this trend line.

[0030] Judgment of abnormal data: The calculated gradients are: (0.67-0.48)=0.19, (0.58-0.67)=-0.09 (abnormal), (0.95-0.58)=0.37 (abnormal), (1.18-0.95)=0.23. The gradient sequence shows a negative value (-0.09) and a peak value (0.37) much larger than the average. This abrupt change severely violates the physical laws of a stable flow field. Therefore, the system can determine that this set of test results is inaccurate, possibly due to external airflow or a brief leak in the sealing strip during measurements at points 3 and 4. The operator should return to the detection end and repeat the measurements until a stable gradient is obtained.

[0031] The foregoing description only illustrates certain exemplary embodiments of the present invention. Undoubtedly, those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the above drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A micro-differential pressure airflow testing device, comprising a detection end (100) of a hot-wire anemometer and an operation terminal (101), characterized in that, It includes a rounded rectangular air guide shroud (1) and a cylindrical body (2) connected to it; A platform (3) is slidably arranged inside the cylinder (2), and the detection end (100) is fixedly installed on the side of the platform (3) facing the rounded rectangular air guide hood (1) and centered.

2. The micro-differential airflow testing device according to claim 1, characterized in that, The platform (3) has a first annular groove, and a transparent acrylic plate (4) is fixedly installed in the first annular groove.

3. The micro-differential airflow testing device according to claim 2, characterized in that, The platform (3) has a second annular groove, and a breathable mesh (5) is fixedly installed in the second annular groove. The outer circumferential radius of the second annular groove is smaller than the inner circumferential radius of the first annular groove.

4. The micro-differential pressure airflow testing device according to claim 3, characterized in that, A cross-shaped reinforcing rib (33) is fixedly installed on one side of the platform (3).

5. The micro-pressure differential airflow testing device according to claim 1, characterized in that, The port of the rounded rectangular air guide shroud (1) is provided with a soft rubber pad (11).

6. The micro-differential airflow testing device according to claim 1, characterized in that, The rounded rectangular air guide hood (1) is frustum-shaped, and its narrow opening is connected to the cylinder (2).

7. The micro-differential airflow testing device according to claim 1, characterized in that, An adapter (21) is fixedly provided on the inner wall of the port of the cylindrical body (2) relative to the rounded rectangular air guide hood (1), and the adapter (21) is rotatably connected to the operating terminal (101).

8. The micro-differential airflow testing device according to claim 1, characterized in that, The port of the cylinder (2) is fixedly provided with a fixed cylinder (22) extending inward, and the outer wall of the fixed cylinder (22) is slidably provided with a movable cylinder (23). The number of movable cylinders (23) is several, and they are nested together and slidably connected. The platform (3) is fixedly installed on the port of the last-stage movable cylinder (23).

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