Sand and dust test chamber

Abstract

The utility model belongs to sand dust test technical field discloses a sand dust test box, the test box body is equipped with the test cavity that is used for putting the article that needs to carry out the experiment, and the top of test box body is equipped with the static pressure cavity and dust / air mixer that communicate, the bottom of test box body is equipped with the spiral feeder that is used for adding sand dust to dust / air mixer, the bottom of test box body is equipped with the recovery part, and the recovery part is connected between dust / air mixer through circulation air duct, and is equipped with fan on circulation air duct, and the air outlet end of dust / air mixer is communicated with static pressure cavity, and the bottom of static pressure cavity is equipped with the vent, and is equipped with the flow equalizing plate at the vent. The utility model avoids the problem that the wind speed and dust concentration are inconsistent at each point in the box in the traditional design, ensures the consistency and repeatability of test conditions, so that the test results of different time and different batches have comparability.

Description

Technical Field

[0001] This utility model relates to the field of sand and dust testing technology, and in particular to a sand and dust testing chamber. Background Technology

[0002] The core function of sand and dust test chambers can be summarized as follows: by simulating harsh sand and dust environments, they test the sealing performance and resistance of products, thereby assessing their reliability and lifespan. They are widely used in production and daily life. However, existing sand and dust test chambers suffer from uneven airflow organization, leading to inconsistent dust concentration distribution and affecting the repeatability and comparability of test results. Utility Model Content

[0003] To overcome the technical defects of the existing technology, this utility model provides a sand and dust test chamber, which has a simple structure and avoids the problem of inconsistent wind speed and dust concentration at different points in the chamber in traditional designs. It ensures the consistency and repeatability of test conditions, making test results from different times and batches comparable.

[0004] The technical solution adopted by this utility model is: a sand and dust test chamber, including a test chamber body, the test chamber body having a test cavity for placing the items to be tested, and the top of the test chamber body having a connected static pressure chamber and a dust / air mixer, the bottom of the test chamber body having a screw feeder for adding sand and dust to the dust / air mixer, the bottom of the test chamber body having a recovery section, and the recovery section being connected to the dust / air mixer via a circulating air duct, the circulating air duct having a fan, and the air outlet of the dust / air mixer being connected to the static pressure chamber, and the bottom of the static pressure chamber having a vent, the vent having a flow equalization plate, the dust-mixed gas being blown towards the surface of the tested items through the flow equalization plate to form a vertical laminar airflow, and the test chamber having a dust concentration sensor for detecting dust concentration.

[0005] Preferably, the dust / air mixer includes a venturi tube and a collection cylinder. The bottom of the collection cylinder is connected to the throat of the venturi tube via a dust inlet pipe, and the diffuser end of the venturi tube is connected to the static pressure chamber. The inlet end of the venturi tube is connected to the circulating air duct, and the outlet end of the screw feeder is connected to the top of the collection cylinder. A connecting pipe is provided between the collection cylinder and the air duct.

[0006] Preferably, the diffuser end of the venturi tube is provided with a swirl vane, and the venturi tube and the swirl vane are made of wear-resistant material.

[0007] Preferably, the device also includes a controller, wherein the dust concentration sensor and the screw feeder are both connected to the controller. The dust concentration range for the test is set on the controller, and the dust concentration in the test chamber is detected by the dust concentration sensor. When the dust concentration in the test chamber is within the set dust concentration range, the screw feeder stops working; if it is too low, the screw feeder works until the dust concentration in the test chamber is within the set dust concentration range.

[0008] Preferably, the recovery section has a conical structure.

[0009] Preferably, the circulating air duct is connected to the upper end of the recovery section.

[0010] The beneficial effects of this utility model are as follows: 1. In this utility model, the sand and dust fed from the screw feeder enter the dust / air mixer for mixing. Then, under the action of the fan, the dust is carried into the static pressure chamber. The static pressure chamber can reduce the speed of the high-speed, turbulent airflow and stabilize the pressure. Furthermore, through the flow equalization plate at the bottom, the airflow can be evenly distributed across the entire cross-section of the test chamber. This allows the sand and dust mixture gas to be blown vertically and steadily onto the entire surface of the test object like a uniform "air curtain." This avoids the problem of inconsistent wind speed and dust concentration at different points in the chamber in traditional designs, ensuring the consistency and repeatability of test conditions, and making the test results from different times and batches comparable. Attached Figure Description

[0011] One or more embodiments are illustrated by way of example with reference numerals in the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements with the same reference numerals in the drawings are denoted as similar elements. Unless otherwise stated, the figures in the drawings are not to be limited by scale.

[0012] Figure 1 This is a schematic diagram of the overall structure of this utility model; Figure 2 This is a schematic diagram of the structure of the dust / air mixer of this utility model; Figure 3 This is a schematic diagram of the swirl vane structure of this utility model.

[0013] Explanation of reference numerals in the attached figures: 1. Test chamber; 2. Test cavity; 3. Static pressure chamber; 4. Dust / air mixer; 401. Venturi tube; 402. Collection cylinder; 403. Dust inlet pipe; 404. Swirl vane; 5. Screw feeder; 6. Recovery section; 7. Circulating air duct; 8. Fan; 9. Ventilation outlet; 10. Flow equalization plate; 11. Controller. Detailed Implementation

[0014] To make the objectives, technical solutions, and advantages of this utility model clearer, the various embodiments of this utility model will be described in detail below with reference to the accompanying drawings. However, those skilled in the art will understand that many technical details have been provided in the various embodiments of this utility model to facilitate a better understanding of this application. However, the technical solutions claimed in the claims of this application can be implemented even without these technical details and with various variations and modifications based on the following embodiments.

[0015] like Figures 1-3 As shown, this embodiment provides a sand and dust test chamber, including a test chamber body 1. The test chamber body 1 is provided with a test chamber 2 for placing the items to be tested. The top of the test chamber body 1 is provided with a static pressure chamber 3 and a dust / air mixer 4 connected together. The bottom of the test chamber body 1 is provided with a screw feeder 5 for adding sand and dust to the dust / air mixer 4. The bottom of the test chamber body 1 is provided with a recovery section 6, and the recovery section 6 is connected to the dust / air mixer 4 via a circulation duct 7. A fan 8 is provided on the circulation duct 7, and the air outlet of the dust / air mixer 4 is connected to the static pressure chamber 3. The bottom of the static pressure chamber 3 is provided with a vent 9, and a flow equalization plate 10 is provided at the vent 9. The dust-mixed gas forms a vertical laminar airflow that blows toward the surface of the test items through the flow equalization plate 10. A dust concentration sensor 11 for detecting dust concentration is provided in the test chamber 2. The sand and dust fed from the screw feeder enter the dust / air mixer for mixing. Then, under the action of the fan, the dust is carried into the static pressure chamber. The static pressure chamber reduces the high-speed, turbulent airflow velocity and stabilizes the pressure. Furthermore, the airflow is evenly distributed across the entire cross-section of the test chamber by the flow equalization plate at the bottom. This allows the sand and dust mixture to act like a uniform "air curtain," vertically and steadily blowing onto the entire surface of the test object. This avoids the problem of inconsistent wind speed and dust concentration at different points within the chamber in traditional designs, ensuring the consistency and repeatability of test conditions and making test results from different times and batches comparable.

[0016] The screw feeder can stably, continuously, and controllably deliver dust to the mixer, avoiding fluctuations and unevenness caused by manual addition. The mixer, in turn, ensures that the dust and air are fully and evenly mixed.

[0017] Through a closed-loop design of "recovery section -> circulating air duct -> fan -> mixer -> static pressure chamber -> test chamber -> recovery section", dust can be recycled. This not only saves consumables, but more importantly, the system can quickly reach and maintain a constant target dust concentration, ensuring the stability of the concentration during long-term testing.

[0018] The dust / air mixer 4 includes a venturi tube 401 and a collection cylinder 402. The bottom of the collection cylinder 402 is connected to the throat of the venturi tube 401 via a dust inlet pipe 403, and the diffuser end of the venturi tube 401 is connected to the static pressure chamber 3. The inlet end of the venturi tube 401 is connected to the circulating air duct 7, and the outlet end of the screw feeder 5 is connected to the top of the collection cylinder 402. A connecting pipe is provided between the collection cylinder 402 and the air duct. After dust is sucked in at the throat of the venturi tube, it immediately enters its diffuser section. In the diffuser section, the pipe diameter gradually increases, the airflow velocity slows down, and the static pressure recovers. This "deceleration and pressurization" process provides sufficient **turbulence and mixing space** for dust and air, allowing dust particles to mix fully and uniformly with the air to form a stable aerosol state. This avoids **agglomeration, clumping, or settling** of dust due to uneven mixing, ensuring that the dust concentration entering the test chamber is uniform. It serves as a temporary dust storage and buffer container. Dust fed in from the top by the screw feeder accumulates here, forming a stable "dust pool" that ensures a continuous supply of dust to be drawn into the venturi tube.

[0019] The crucial role of connecting pipes: This is one of the essences of the design.

[0020] Pressure balance: The connecting pipe connects the upper part of the collection cylinder to the positive pressure zone of the air duct. This ensures that the air pressure at the top of the collection cylinder is basically the same as the air pressure in the air duct, avoiding excessive negative pressure inside the collection cylinder caused by the Venturi tube sucking from the bottom. Without this connecting pipe, the strong suction might create a vacuum inside the cylinder, hindering the smooth falling of dust and even causing dust to "bridge" and blockage.

[0021] Promoting dust fluidization: A small amount of airflow entering the collection cylinder from the connecting pipe can "loosen" or "fluidize" the dust in the upper part, making it easier for it to flow downwards and enter the dust inlet pipe.

[0022] A stable differential pressure is established: the system creates a stable and controllable pressure difference between the pressure near the top of the collection cylinder and the negative pressure at the throat of the venturi tube at the bottom dust inlet. This pressure difference precisely determines the rate at which dust is drawn in, making dust transport very stable.

[0023] The diffuser end of the Venturi tube 401 is provided with a swirl vane 404, and the Venturi tube 401 and the swirl vane 404 are made of wear-resistant material.

[0024] The system also includes a controller. The dust concentration sensor 11 and the screw feeder 5 are both connected to the controller. The controller sets the dust concentration range for the test. The dust concentration sensor detects the dust concentration in the test chamber. When the dust concentration in the test chamber is within the set range, the screw feeder 5 stops working; if it is too low, the screw feeder 5 continues to operate until the dust concentration in the test chamber is within the set range. The recovery section 6 has a conical structure. The circulating air duct 7 is connected to the upper end of the recovery section.

[0025] Furthermore, any content not described in detail in this specification is existing technology known to those skilled in the art.

[0026] During operation, the sand and dust fed from the screw feeder 5 enter the dust / air mixer 4 for mixing. Then, under the action of the fan 8, the dust is carried into the static pressure chamber 3. The static pressure chamber 3 reduces the speed and stabilizes the pressure of the high-speed, turbulent airflow. Furthermore, the airflow is evenly distributed across the entire cross-section of the test chamber 2 by the flow equalization plate 10 at the bottom. This allows the sand and dust mixture to act like a uniform "air curtain," vertically and steadily blowing onto the entire surface of the test object. This avoids the problem of inconsistent wind speed and dust concentration at different points within the chamber in traditional designs, ensuring the consistency and repeatability of test conditions, and making test results from different times and batches comparable.

[0027] Those skilled in the art will understand that the above embodiments are specific examples of implementing the present invention, and in practical applications, various changes can be made to them in form and detail without departing from the spirit and scope of the present invention.

Claims

1. A sand and dust test chamber, characterized in that: The test chamber includes a test chamber (1), which has a test cavity (2) for placing the items to be tested. The top of the test chamber (1) has a connected static pressure chamber (3) and a dust / air mixer (4). The bottom of the test chamber (1) has a screw feeder (5) for adding sand / dust to the dust / air mixer (4). The bottom of the test chamber (1) has a recovery section (6), and the recovery section (6) is connected to the dust / air mixer (4). The dust / air mixer (4) is connected by a circulating air duct (7), and a fan (8) is provided on the circulating air duct (7). The air outlet of the dust / air mixer (4) is connected to the static pressure chamber (3). The bottom of the static pressure chamber (3) is provided with a vent (9). A flow equalization plate (10) is provided at the vent (9). The dust-mixed gas forms a vertical laminar airflow that blows toward the surface of the experimental item through the flow equalization plate (10). A dust concentration sensor (11) for detecting dust concentration is provided in the test chamber (2).

2. The sand and dust test chamber according to claim 1, characterized in that: The dust / air mixer (4) includes a venturi tube (401) and a collection cylinder (402). The bottom of the collection cylinder (402) is connected to the throat of the venturi tube (401) via a dust inlet pipe (403). The diffuser end of the venturi tube (401) is connected to the static pressure chamber (3). The inlet end of the venturi tube (401) is connected to the circulating air duct (7). The outlet end of the screw feeder (5) is connected to the top of the collection cylinder (402). A connecting pipe is provided between the collection cylinder (402) and the air duct.

3. The sand and dust test chamber according to claim 2, characterized in that: The diffuser end of the Venturi tube (401) is provided with a swirl vane (404), and the Venturi tube (401) and the swirl vane (404) are made of wear-resistant material.

4. The sand and dust test chamber according to claim 1, characterized in that: It also includes a controller. The dust concentration sensor (11) and the screw feeder (5) are both connected to the controller. The dust concentration range for the test is set on the controller. The dust concentration in the test chamber is detected by the dust concentration sensor. When the dust concentration in the test chamber is within the set dust concentration range, the screw feeder (5) stops working. If it is too low, the screw feeder (5) works until the dust concentration in the test chamber is within the set dust concentration range.

5. The sand and dust test chamber according to claim 1, characterized in that: The recovery section (6) has a conical structure.

6. The sand and dust test chamber according to claim 1, characterized in that: The circulating air duct (7) is connected to the upper end of the recovery section.

Images