Carbon paper air permeability tester

Abstract

The utility model relates to a carbon paper air permeability tester, and belongs to the technical field of detection equipment. The tester comprises an instrument shell, a sample tray is installed on the instrument shell through a pressure sensor, an air cavity is formed in the sample tray, and a pressurizing mechanism is connected to the air cavity; a pressing device is arranged above the sample tray and comprises a servo motor, a lead screw, a lead screw nut, a push cylinder, a buffer mechanism and a sample pressing upper cover, and a differential pressure gauge is arranged between the sample pressing upper cover and the air cavity. The tester can quickly and accurately adjust the downward pressure of the carbon paper through the servo motor, and accurately control the downward pressure through the feedback of the pressure sensor, thereby ensuring that the clamping force can ensure that the carbon paper does not move and the measurement result is accurate; and the carbon paper is not easy to damage. And the downward pressure can be buffered through the buffer mechanism, so that the downward pressure on the carbon paper is slowly increased, and the carbon paper can be further prevented from being damaged. The problems that existing detection equipment is severely lagged in adjustment and is not easy to adjust quickly and accurately are solved.

Description

Technical Field

[0001] This utility model relates to a carbon paper air permeability tester, belonging to the technical field of testing equipment. Background Technology

[0002] Air permeability testers, as key equipment for evaluating the gas permeability of porous materials, are widely used in textiles, medical devices, and environmental protection. Carbon paper, in particular, must undergo air permeability testing before use to ensure reliability. Air permeability testers typically clamp the material, apply pressure to one side, and measure the pressure difference between the two sides to determine air permeability. Because pressure needs to be applied to one side of the material, a certain clamping force is required to hold it in place. The clamping force needs to be adjusted according to the material; if the clamping force is too small, the material can easily move under pressure, leading to inaccurate measurements; if the clamping force is too large, it can easily damage the material.

[0003] Patent application CN119804267A discloses a device and method for testing the air permeability of tipping paper for printed cigarettes. The device includes a base, clamping assemblies, and testing components. Two movable clamping assemblies are symmetrically arranged on the base. Two movable testing components are symmetrically arranged between the two clamping assemblies. Each testing component includes a fixed base, a clamping bottom ring, a clamping top ring, and a clamping cylinder. A slot is provided on the inner side of the fixed base. The clamping bottom ring is embedded in the bottom end of the slot, and the clamping top ring is located at the top end of the slot, directly opposite the clamping bottom ring. A clamping cylinder is located at the upper end of the fixed base, and the first piston rod of the clamping cylinder is connected to the clamping top ring. By using the dual testing components, one component is used for suction cleaning and initial testing, followed by a second test using the other component. This provides a basis for subsequent testing of other points on the tipping paper, reducing the testing process and improving the accuracy of air permeability testing.

[0004] The aforementioned testing equipment uses a clamping cylinder as a power source to hold the paper in place for testing, and it can also test the air permeability of carbon paper. Although the clamping force of the clamping cylinder can be adjusted by changing the air pressure of the clamping cylinder, this adjustment is indirect and suffers from significant lag, making it difficult to adjust the clamping force quickly and accurately. Therefore, it is necessary to redesign a carbon paper air permeability tester to solve the above problems. Summary of the Invention

[0005] The purpose of this invention is to provide a carbon paper air permeability tester that can quickly and accurately adjust the clamping force to ensure accurate detection without easily damaging the material.

[0006] The technical solution of this utility model is:

[0007] A carbon paper air permeability tester comprises an instrument housing, a sample tray, an air chamber, a pressurizing mechanism, and a pressing device. Its features include: a sample tray mounted on the instrument housing via a pressure sensor; an air chamber on the sample tray extending through the pressure sensor into the instrument housing; a pressurizing mechanism connected to the air chamber extending into the instrument housing; a support platform mounted above the sample tray via parallel support rods; and a pressing device mounted on the support platform. The pressing device comprises a servo motor, a lead screw, a lead screw nut, a push cylinder, a buffer mechanism, and a pressing cover. A lead screw is movably mounted on the support platform on one side of the servo motor, with a lead screw gear at its top end, connected to the output shaft of the servo motor via an intermediate wheel. A lead screw nut is threaded onto the lead screw. A push cylinder is movably inserted into the support platform via a sleeve, its top end fixedly connected to the lead screw nut. A pressing cover is mounted on the bottom end of the push cylinder via a buffer mechanism. A differential pressure gauge is connected between the pressing cover and the air chamber via a flexible hose.

[0008] The pressurization mechanism includes a blower, which is connected to the bottom of the air chamber via a connecting pipe. A solenoid valve and a flow meter are installed on the connecting pipe between the blower and the air chamber.

[0009] The buffer mechanism consists of a spring positioning plate, pins, and springs. Pins are evenly distributed on the spring positioning plate, and the bottom end of the pins is threaded to the upper cover of the sample pressing. A spring is fitted on the pin between the upper cover of the sample pressing and the spring positioning plate. The spring positioning plate is fixedly connected to the push cylinder.

[0010] A filter screen is installed at the top of the air chamber via a rubber pad.

[0011] The support platform is equipped with a protective cover to shield the rotating parts.

[0012] The instrument housing is equipped with buttons, an operation screen, and a printer. The buttons and operation screen are connected to a servo motor, a fan, a solenoid valve, a pressure sensor, a differential pressure gauge, and a printer, respectively, via a computer.

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

[0014] This carbon paper permeability tester can quickly and accurately adjust the downward pressure on the carbon paper using a servo motor. Feedback from a pressure sensor further refines the control of the downward pressure, ensuring that the clamping force on the carbon paper is sufficient to prevent movement and guarantee accurate measurement results, while also minimizing the risk of damage. A buffer mechanism further cushions the downward pressure, allowing it to increase gradually and preventing direct impact from the pressure plate onto the carbon paper, thus further preventing damage. This solves the problem of existing testing equipment relying on cylinder clamping, which results in significant lag during adjustment and hinders rapid and accurate control. Attached Figure Description

[0015] Figure 1This is a schematic diagram of the structure of this utility model;

[0016] Figure 2 This is an isometric schematic diagram of the pressing device of this utility model;

[0017] Figure 3 This is a cross-sectional schematic diagram of the pressing device of this utility model;

[0018] Figure 4 This is a connection diagram of the pressurization mechanism of this utility model;

[0019] Figure 5 This is a schematic diagram of the sample tray of this utility model;

[0020] Figure 6 This is a cross-sectional schematic diagram of the sample tray of this utility model.

[0021] In the diagram: 1. Instrument housing, 2. Sample tray, 3. Air chamber, 4. Pressure sensor, 5. Support rod, 6. Support platform, 7. Servo motor, 8. Lead screw, 9. Lead screw nut, 10. Push cylinder, 11. Sample pressing cover, 12. Lead screw gear, 13. Intermediate wheel, 14. Sleeve, 15. Differential pressure gauge, 16. Fan, 17. Connecting pipe, 18. Solenoid valve, 19. Flow meter, 20. Spring positioning plate, 21. Pin, 22. Spring, 23. Rubber pad, 24. Filter screen, 25. Protective cover, 26. Button, 27. Operation screen, 28. Printer, 29. Carbon paper sample. Detailed Implementation

[0022] This carbon paper air permeability tester consists of an instrument housing 1, a sample tray 2, an air chamber 3, a pressurizing mechanism, and a pressing device. The sample tray 2 is mounted on the instrument housing 1 via a pressure sensor 4 (SK115 type through-hole shaft-type ring pressure sensor) to support the carbon paper sample. The pressure sensor 4 detects the downward pressure on the sample tray 2, and thus the downward pressure on the carbon paper sample. Based on the detected downward pressure, the clamping force on the carbon paper sample is adjusted quickly and accurately. The sample tray 2 has an air chamber 3 that extends through the pressure sensor 4 into the instrument housing 1. A pressurizing mechanism is connected to the air chamber 3, which injects gas into the air chamber 3 to create air pressure. This air pressure acts on the carbon paper sample, allowing it to permeate and thus enabling the measurement of the carbon paper sample's air permeability. Above the sample tray 2, a support platform 6 is installed via parallel support rods 5. A pressing device is provided on the support platform 6 to press the carbon paper sample onto the sample tray 2, thereby clamping and fixing the carbon paper sample in conjunction with the sample tray 2.

[0023] The pressing device consists of a servo motor 7, a lead screw 8, a lead screw nut 9, a pusher 10, a buffer mechanism, and a pressing cover 11. The lead screw 8 is movably mounted on the support platform 6 on one side of the servo motor 7. A lead screw gear 12 is provided at the top end of the lead screw 8. The lead screw gear 12 is connected to the output shaft of the servo motor 7 through a median wheel 13. The lead screw nut 9 is threaded onto the lead screw 8. The pusher 10 is movably inserted into the support platform 6 through a sleeve 14. The pusher 10 and the sleeve 14 are both square. The top end of the push cylinder 10 is fixedly connected to the lead screw nut 9, and the bottom end of the push cylinder 10 is equipped with a sample pressing cover 11 through a buffer mechanism. A differential pressure gauge 15 is connected to the sample pressing cover 11 and the air chamber 3 through a hose. The differential pressure gauge 15 detects the pressure difference on both sides of the carbon paper sample during the measurement process. When the pressure difference reaches a set value, the air permeability of the carbon paper sample is detected, and the air permeability of the carbon paper sample is calculated based on the air permeability, that is, the air permeability of the carbon paper sample under a specific pressure difference is detected. The function of the servo motor 7 is that during the rotation of the output shaft of the servo motor 7, the servo motor 7 sequentially drives the intermediate wheel 13 and the lead screw gear 12 to rotate, which in turn drives the lead screw 8 to rotate. The rotating lead screw 8 drives the lead screw nut 9 to rise and fall, which in turn drives the push cylinder 10 to rise and fall. During the rising and falling of the push cylinder 10, the sample pressing cover 11 is driven to rise and fall through the buffer mechanism. Thus, the rising and falling sample pressing cover 11, together with the sample tray 2, clamps and fixes the carbon paper sample. Since the servo motor 7 can adjust its speed, number of revolutions, and torque, the downward pressure of the sample pressing cover 11 can be adjusted by adjusting the servo motor 11. Because the adjustment of the servo motor 11 can be applied to the sample pressing cover 11 in real time, the adjustment process is not prone to lag and the clamping force can be adjusted quickly and accurately.

[0024] The pressurization mechanism includes a blower 16, which is connected to the bottom of the air chamber 3 via a connecting pipe 17. A solenoid valve 18 and a flow meter 19 are installed on the connecting pipe 17 between the blower 16 and the air chamber 3. The blower 16, in conjunction with the solenoid valve 18, pressurizes the air chamber 3, thereby pressurizing the bottom of the carbon paper sample and creating a pressure difference across the sample. The flow meter 19 detects the gas flow rate and calculates the air permeability of the carbon paper sample, thus determining its permeability.

[0025] The buffer mechanism consists of a spring positioning plate 20, pins 21, and springs 22. Pins 21 are evenly distributed and inserted into the spring positioning plate 20, with the bottom end of each pin threaded to the sample pressing cover 11. Springs 22 are fitted onto the pins 21 between the sample pressing cover 11 and the spring positioning plate 20. The spring positioning plate 20 is fixedly connected to the push cylinder 10. The function of the springs 22 is to compress the sample pressing cover 11 when the push cylinder 10 presses down on the spring positioning plate 20, thereby compressing the sample pressing cover 11. Because the springs 22 are compressible, they can reduce the force on the sample pressing cover 11 when the spring positioning plate 20 is pressed down, gradually increasing the force on the sample pressing cover 11, and thus gradually increasing the force on the carbon paper sample, thereby preventing rigid collision between the sample pressing cover 11 and the carbon paper sample and protecting the carbon paper sample.

[0026] A filter screen 24 is installed at the top of the gas chamber 3 via a rubber pad 23 to filter impurities in the gas, making it less likely for impurities in the gas to accumulate at the bottom of the carbon paper sample, thus facilitating the retesting of the carbon paper sample.

[0027] The support platform 6 is equipped with a protective cover 25 that shields the rotating components (servo motor output shaft, intermediate wheel, lead screw gear).

[0028] The instrument housing 1 is equipped with a button 26 for inputting control commands, an operation screen 27 for inputting parameters and commands, and a printer 28 for printing input parameters, test data, and test results. The button 26 and the operation screen 27 are respectively connected to the servo motor 7, the fan 16, the solenoid valve 18, the pressure sensor 4, the differential pressure gauge 15, and the printer 28 via a computer.

[0029] When the carbon paper permeability tester is working, the preset carbon paper sample type, clamping force, and pressure difference setting value are selected on the operation screen 27. Based on the input on the operation screen 27, the computer calculates and outputs parameters to the servo motor 7, controlling its speed, revolutions, and torque, thereby controlling the clamping force. After input, a start command is sent to the computer via the operation screen 27 or button 26. The computer starts the servo motor 7, which sequentially drives the sample pressing cover 11 downwards through the intermediate wheel 13, lead screw gear 12, lead screw 8, lead screw nut 9, push cylinder 10, and buffer mechanism. The sample pressing cover 11 presses the carbon paper sample firmly onto the sample tray 2. During the pressing process, the pressure sensor 4 detects the downward pressure on the carbon paper sample and adjusts the downward pressure accordingly. After clamping the carbon paper sample, the fan 16 and solenoid valve 18 are activated to pressurize the air chamber 3, thereby pressurizing the bottom of the carbon paper sample. During pressurization, the pressure difference across the carbon paper sample is detected by differential pressure gauge 15. When the pressure difference reaches the set value, the fan 16 is stopped and the solenoid valve 18 is closed. At the same time, the gas flow rate is recorded by flow meter 19 when the pressure difference reaches the set value, and the air permeability of the carbon paper sample under this pressure difference is calculated using the gas flow rate.

[0030] This carbon paper permeability tester can quickly and accurately adjust the downward pressure on the carbon paper using a servo motor. Feedback from a pressure sensor further refines the control of the downward pressure, ensuring that the clamping force on the carbon paper is sufficient to prevent movement and guarantee accurate measurement results, while also minimizing the risk of damage. A buffer mechanism further cushions the downward pressure, allowing it to increase gradually and preventing direct impact from the pressure plate onto the carbon paper, thus further preventing damage. This solves the problem of existing testing equipment relying on cylinder clamping, which results in significant lag during adjustment and hinders rapid and accurate control.

Claims

1. A carbon paper air permeability tester, which is composed of an instrument shell (1), a sample supporting disc (2), an air cavity (3), a pressurizing mechanism and a pressing device, characterized in that: The instrument shell (1) is provided with a sample supporting disc (2) through a pressure sensor (4), the sample supporting disc (2) is provided with an air cavity (3), the air cavity (3) extends into the instrument shell (1) through the pressure sensor (4), and a pressurizing mechanism is connected to the air cavity (3) extending into the instrument shell (1); a supporting table (6) is mounted on the sample supporting disc (2) through parallelly arranged supporting rods (5), and the supporting table (6) is provided with a pressing device; the pressing device is composed of a servo motor (7), a lead screw (8), a lead screw nut (9), a pushing cylinder (10), a buffer mechanism and a sample pressing cover (11), the lead screw (8) is movably mounted on one side of the supporting table (6), a lead screw gear (12) is arranged at the top end of the lead screw (8), and the lead screw gear (12) is connected with the output shaft of the servo motor (7) through a transmission wheel (13); the lead screw nut (9) is threadedly mounted on the lead screw (8), the pushing cylinder (10) is movably inserted into the sleeve (14) on the supporting table (6), the top end of the pushing cylinder (10) is fixedly connected with the lead screw nut (9), the bottom end of the pushing cylinder (10) is provided with the sample pressing cover (11) through the buffer mechanism, and the sample pressing cover (11) is connected with the air cavity (3) through a hose and provided with a differential pressure gauge (15).

2. The carbon paper air permeability tester of claim 1, wherein: The pressurizing mechanism comprises a fan (16), and the fan (16) is connected to the bottom of the air cavity (3) through a communication pipe (17), and the communication pipe (17) between the fan (16) and the air cavity (3) is provided with an electromagnetic valve (18) and a flowmeter (19).

3. The carbon paper air permeability tester of claim 1, wherein: The buffer mechanism is composed of a spring positioning disc (20), a pin (21) and a spring (22), the pins (21) are evenly inserted into the spring positioning disc (20), the bottom end of the pin (21) is threadedly connected with the sample pressing cover (11), and the spring (22) is sleeved on the pin (21) between the sample pressing cover (11) and the spring positioning disc (20); the spring positioning disc (20) is fixedly connected with the pushing cylinder (10).

4. The carbon paper air permeability tester of claim 1, wherein: The air cavity (3) is provided with a filter screen (24) through a rubber pad (23) at the top.

5. The carbon paper air permeability tester of claim 1, wherein: The supporting table (6) is provided with a protective cover (25) for shielding the rotating part.

6. The carbon paper air permeability tester of claim 1, wherein: The instrument shell (1) is provided with a button (26), an operation screen (27) and a printer (28), and the button (26) and the operation screen (27) are respectively connected with the servo motor (7), the fan (16), the electromagnetic valve (18), the pressure sensor (4), the differential pressure gauge (15) and the printer (28) through a computer.

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