Device for testing air content of concrete under constant temperature and humidity

Abstract

The invention provides a device for testing the gas content of concrete at constant temperature and humidity, and relates to the field of testing of the gas content of concrete. The device for testing the air content of the concrete under the constant temperature and humidity comprises a bowl body and a bowl cover, a constant-temperature chamber, a cavity and a pressurizing chamber are arranged in the bowl body, a rotary drum for storing the concrete is rotatably mounted on the inner side of the bowl body, an air inlet and an air outlet are formed in the cavity, and an opening is formed in the rotary drum; according to the device for testing the air content of the concrete under the constant temperature and humidity, different levels of chambers can independently and accurately control and adjust different pressure ranges, the chamber with the highest pressure can preliminarily measure and balance larger bubbles, and the chambers with the lower pressure can measure medium-sized and tiny bubbles respectively; the grading measurement mode can more accurately capture pressure changes generated by bubbles of different sizes, and compared with a mode of switching pressure through a single air pump, the air content in concrete can be more accurately measured.

Description

Technical Field

[0001] The invention relates to the field of concrete air content testing, in particular to a device for testing concrete air content under constant temperature and humidity. Background Art

[0002] Concrete air content test is a technical means for determining the percentage of gas volume contained in concrete to the total volume of concrete, which plays an important role in concrete quality control and performance research. The air content in concrete has a significant impact on its freeze-thaw resistance. The right amount of air content can form tiny closed bubbles inside the concrete, which provide space for water to freeze and expand during freeze-thaw cycles, relieve internal stress, and improve freeze resistance. Through air content testing, it can ensure that concrete has sufficient durability in harsh environments, such as hydraulic structures, roads and bridges in cold areas. Hydraulic structures such as dams, canals, and ports are in a water environment for a long time and are strongly affected by freeze-thaw cycles. They have strict requirements on the air content of concrete and need to test the air content to ensure the impermeability and freeze resistance of the structure. At present, the commonly used method for determining the air content of concrete is the air pressure method, that is, using a concrete air content meter, the concrete mixture is placed in the container of the air content meter, and the pressure in the container reaches a certain value by applying air pressure. Then, the air content of concrete is calculated based on the pressure change and related formulas. This method is relatively simple to operate and is suitable for construction sites and laboratories.

[0003] At present, the traditional concrete air content test widely adopts the method of loading the concrete mixture into the air content meter container in three layers, and each layer is evenly tamped with a tamping rod for a certain number of times to achieve concrete density. After the last layer is tamped, the surface is smoothed with a trowel. However, the distribution range of bubble size inside concrete is extremely wide, covering a variety of types from larger bubbles to tiny bubbles.

[0004] The air pressure method commonly used in testing devices for the air content of concrete is used to measure the air content. It can measure relatively accurately when facing larger bubbles, because larger bubbles have a significant impact on pressure changes and are easy to detect. However, when facing tiny bubbles, it is difficult to accurately capture such subtle changes due to the weak impact of tiny bubbles on pressure changes. As a result, in some scenarios where high precision is required for the measurement of tiny bubble content, accurate measurement cannot be performed, which in turn affects the evaluation of the true air content of concrete, resulting in deviations in the accurate judgment of concrete performance, which is not conducive to the precise control of concrete quality. Therefore, there is an urgent need for a device that can effectively solve the problem of tiny bubble measurement and more accurately measure the air content of concrete. Summary of the invention

[0005] In view of the deficiencies of the prior art, the present invention provides a testing device for the air content of concrete under constant temperature and humidity, which solves the problem of inaccurate measurement of tiny bubbles.

[0006] To achieve the above objectives, the present invention is implemented through the following technical solutions: a testing device for the air content of concrete under constant temperature and humidity, comprising a bowl body and a bowl cover, wherein a constant temperature chamber, a cavity and a pressurization chamber are arranged in the bowl body, a rotating drum for storing concrete is rotatably installed on the inner side of the bowl body, an air inlet and an air outlet are provided in the cavity, an opening is provided inside the rotating drum, the pressurization chamber comprises chambers with successively increasing air pressure, each chamber is provided with an exhaust port for conveying gas to the opening, both ends of the rotating drum are fixedly connected with a turntable, a rotating rod for rotation is installed between the two turntables, and a transmission mechanism is installed on the outer side of the rotating rod.

[0007] A star-shaped combination pad is provided inside the rotating drum, and the combination pad includes several arc pads A, several arc pads B and several inclined pads. The arc pad A is in contact with the rotating drum, and each arc pad A is fixedly connected to a support rod at the arc surface close to the rotating rod. When the rotating rod rotates, the movement of the support rod is controlled by a transmission mechanism, and each arc pad B is fixedly connected to a push rod at the arc surface away from the rotating rod. The push rod squeezes the arc pad B toward the rotating rod through a spring assembly.

[0008] Preferably, the outside of the constant temperature chamber is connected to an air inlet pipe B for delivering warm air to the constant temperature chamber, and a valve is installed at one end of the air inlet pipe B.

[0009] Preferably, the outside of each chamber is connected to an air inlet pipe A, and a valve is installed at one end of each air inlet pipe A.

[0010] Preferably, a driving motor A is installed inside one of the turntables, an output end of the driving motor A is fixedly connected to the rotating rod, and one end of the other turntable is connected to an external motor.

[0011] Preferably, the transmission mechanism includes a rotating wheel, a guide wheel for rotation, a plurality of fixed columns and a plurality of push-pull plates. The rotating wheel is fixedly connected to the rotating rod, a plurality of sliding grooves are provided in the rotating wheel, each push-pull plate is slidably connected to the sliding groove adjacent to it, and is fixedly connected to the adjacent support rods, the guide wheel is rotatably connected to the rotating rod, a plurality of arc grooves are provided inside the guide wheel, each fixed column is slidably connected to the arc groove adjacent to it, and is fixedly connected to the push-pull plate adjacent to it.

[0012] Preferably, the outer side of the rotating rod is fixedly connected to a mounting plate, a driving motor B is fixedly mounted on one side of the mounting plate, the output end of the driving motor B is fixed to the gear B, the outer side of the rotating rod is rotatably connected to a gear A, gear A is fixedly connected to one of the guide wheels, the outer surface of gear A is meshingly connected to gear B, and the output end of the driving motor B is fixedly connected to gear B.

[0013] Preferably, a feed hopper is fixedly connected in the cavity, and a sealing cover is provided at the inlet of the feed hopper, and when the opening moves to a position corresponding to the feed hopper, it is used to transport concrete into the opening.

[0014] Preferably, the upper surface and the bottom surface of the combined pad are in close contact with the two turntables respectively.

[0015] Preferably, the arc pad A and the arc pad B are both made of silicone material, and the tilt pad is made of rubber material.

[0016] Preferably, the spring assembly includes a spring, an insertion rod, a fixed cylinder and a fixed plate. The fixed cylinder is slidably connected to the inner wall of the rotating cylinder. An arc-shaped piece is installed on the outer side of the fixed cylinder. The arc-shaped piece is slidably connected to the rotating cylinder. The insertion rod is slidably connected to the fixed cylinder, and a seal is provided at the intersection of the two. The other end of the insertion rod is fixedly connected to a push rod close to it, the fixed plate is fixedly connected to the insertion rod, and both ends of the spring are fixedly connected to the fixed cylinder and the fixed plate respectively, and the spring is in a compressed state.

[0017] Compared with the prior art, the present invention has the following beneficial effects: 1. The testing device for concrete air content under constant temperature and humidity applies successively increasing air pressure to three chambers through three air inlet pipes A. Chambers of different levels can independently and accurately control and adjust different pressure ranges. The chamber with the highest pressure can perform preliminary measurement and balance of larger bubbles, and the chamber with lower pressure measures medium-sized and tiny bubbles respectively. This graded measurement method can more accurately capture the pressure changes caused by bubbles of different sizes. Compared with a single air pump switching pressure, it can more accurately measure the air content in concrete. The multi-stage chamber structure forms a relatively stable pressure environment in each chamber. Each chamber has an independent pressure regulation and balancing system. When the air pump provides pressure to the next-level chamber, the pressure of the previous-level chamber is not disturbed, thereby reducing the influence of pressure fluctuations on the measurement results and improving the accuracy and reliability of the measurement.

[0018] 2. In the test device for the air content of concrete under constant temperature and humidity, the wheel, guide wheel and drum can all rotate independently or work together, and their respective rotation control is realized through different drive motors and transmission mechanisms, providing a variety of operation modes for the test of the air content of concrete. For example, the rotation of the wheel can control the rotation of the combined pad to realize the feeding and mixing of concrete; the rotation of the guide wheel can adjust the distance between the combined pad and the drum, so that the concrete can flow or separate from each other; the rotation of the drum facilitates the feeding of concrete and the test docking of different chambers. This flexible design adapts to the needs of different stages in the test process; the combination of multiple rotation modes avoids complex manual operations and improves the degree of automation of the test process. The operator can complete a series of operations such as concrete loading, mixing, compacting and testing by controlling different drive motors, reducing the errors and uncertainties that may be caused by manual intervention.

[0019] 3. The testing device for the air content of concrete under constant temperature and humidity rotates the drum to make the opening correspond to the feed hopper, puts the concrete into the drum, and then uses the wheel to drive the combined pad to rotate, so that the concrete enters the several closed spaces formed between the combined pad and the drum in turn, achieving uniform feeding. This uniform loading method avoids the problem of concrete accumulation or uneven distribution in the drum, and lays the foundation for the subsequent accurate measurement of the air content. The star-shaped structure of the combined pad can stir the concrete during the rotation process, so that the bubbles in the concrete are evenly distributed. At the same time, the guide wheel is used to adjust the distance between the combined pad and the drum, so that the concrete can flow and then be separated, which further promotes the uniform dispersion of bubbles and helps to improve the accuracy of the air content test. The inclined pad of the combined pad is made of rubber material, which can squeeze the concrete and compact it when it returns to its original position. This process does not require manual compaction, avoids the problem of uneven distribution of bubbles caused by excessive or insufficient manual compaction, and ensures the consistency of the internal structure of the concrete, so that the measured air content can more truly reflect the actual situation of the concrete. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the overall structure of the present invention; Figure 2 It is a cross-sectional view of the front view of the bowl body of the present invention; Figure 3 It is a cross-sectional view of a top view of the bowl body of the present invention; Figure 4 It is a cross-sectional view of the bowl body and the top view of the rotating drum of the present invention; Figure 5 For the present invention Figure 4 A schematic diagram of the structure enlargement in the middle; Figure 6 A sectional view of a top view of a composite mat of the present invention; Figure 7 is a cross-sectional view of a top view of a rotating rod of the present invention; Figure 8 is a cross-sectional view of a top view of a runner of the present invention; Fig. 9 It is a cross-sectional view of a bottom view of the bowl body of the present invention; Fig.10 It is a schematic diagram of the support rod structure of the present invention.

[0021] Among them: 1. bowl body; 2. bowl cover; 3. constant temperature chamber; 4. cavity; 5. pressurization chamber; 6. rotating drum; 7. air inlet; 8. air outlet; 9. opening; 10. chamber; 11. exhaust port; 12. turntable; 13. rotating rod; 14. combination pad; 141. arc pad A; 142. arc pad B; 143. tilting pad; 15. support rod; 16. push rod; 17. air inlet pipe B; 18. air inlet pipe A; 19. driving motor A; 20. rotating wheel; 21. guide wheel; 22. fixing column; 23. push-pull plate; 24. arc groove; 25. mounting plate; 26. gear B; 27. feed hopper; 28. insertion rod; 29. ​​fixing drum; 30. fixing plate; 31. arc sheet. DETAILED DESCRIPTION

[0022] like Figure 1-Figure 10As shown, a testing device for the air content of concrete under constant temperature and humidity comprises a bowl body 1 and a bowl cover 2, the bowl body 1 and the bowl cover 2 are sealed and installed, a constant temperature chamber 3, a cavity 4 and a pressurization chamber 5 are arranged in the bowl body 1, the outside of the constant temperature chamber 3 is connected with an air inlet pipe B17 for conveying warm air to the constant temperature chamber 3, a valve is installed at one end of the air inlet pipe B17, and the warm air is conveyed to the constant temperature chamber 3 through the air inlet pipe B17 to provide a constant temperature environment for the concrete, a feed hopper 27 is fixedly connected in the cavity 4, a sealing cover is provided at the inlet of the feed hopper 27, and when the opening 9 moves to a position corresponding to the feed hopper 27, it is used to convey concrete to the opening 9, and a valve for storing concrete is rotatably installed on the inside of the bowl body 1 The rotary drum 6 of the soil is in close contact with the bowl body 1. An air inlet 7 and an air outlet 8 are provided in the cavity 4. An opening 9 is provided inside the rotary drum 6. The pressurized chamber 5 includes chambers 10 with increasing air pressure. The outside of each chamber 10 is connected with an air inlet pipe A18. A valve is installed at one end of each air inlet pipe A18. An exhaust port 11 for conveying gas to the opening 9 is provided in each chamber 10. Turntables 12 are fixedly connected at both ends of the rotary drum 6. A driving motor A19 is installed inside one of the turntables 12. The output end of the driving motor A19 is fixedly connected to the rotating rod 13. One end of the other turntable 12 is connected to an external motor. The driving motor A19 is used to drive the rotating The rod 13 rotates, and the external motor is used to drive the turntable 12 to rotate. A rotating rod 13 for rotation is installed between the two turntables 12. A transmission mechanism is installed on the outside of the rotating rod 13. The number of transmission mechanisms is two, and the two transmission mechanisms are respectively located at the two ends of the rotating rod 13. The transmission mechanism includes a rotating wheel 20, a guide wheel 21 for rotation, a plurality of fixed columns 22 and a plurality of push-pull plates 23. The rotating wheel 20 is fixedly connected to the rotating rod 13, and a plurality of slide grooves are arranged in the rotating wheel 20. Each push-pull plate 23 is slidably connected to the slide groove adjacent to it, and is fixedly connected to the adjacent support rod 15. The guide wheel 21 is rotatably connected to the rotating rod 13, and a plurality of fixed columns 22 are arranged inside the guide wheel 21. An arc groove 24 is formed, and each fixed column 22 is slidably connected to the arc groove 24 adjacent to it, and is fixedly connected to the push-pull plate 23 adjacent to it. When the guide wheel 21 rotates, the fixed column 22 can be pushed to move through the arc groove 24, so that the push-pull plate 23 drives the support rod 15 to move. The outer side of the rotating rod 13 is fixedly connected to a mounting plate 25, and a driving motor B is fixedly installed on one side of the mounting plate 25. The output end of the driving motor B is fixed to a gear B26. The outer side of the rotating rod 13 is rotatably connected to a gear A, and the gear A is fixedly connected to one of the guide wheels 21. The outer surface of the gear A is meshingly connected to the gear B26, and the output end of the driving motor B is fixedly connected to the gear B26.

[0023] A star-shaped combination pad 14 is provided inside the rotating drum 6. The upper surface and the bottom surface of the combination pad 14 are in close contact with the two rotating disks 12 respectively to form a closed space. The combination pad 14 includes a plurality of arc pads A141, a plurality of arc pads B142 and a plurality of inclined pads 143. The arc pad A141 is in contact with the rotating drum 6. The arc pad A141 and the arc pad B142 are both made of silicone material. The inclined pad 143 is made of rubber material. Each arc pad A141 is fixedly connected to a support rod 15 at the arc surface close to the rotating rod 13. When the rotating rod 13 rotates, the support rod 15 is controlled to move by the transmission mechanism. Each arc pad B142 is away from the rotating rod 13. The arc surface is fixedly connected with a push rod 16, and the push rod 16 squeezes the arc pad B142 in the direction close to the rotating rod 13 through the spring assembly. The spring assembly includes a spring, an insertion rod 28, a fixed cylinder 29 and a fixed plate 30. The fixed cylinder 29 is slidably connected to the inner wall of the rotating cylinder 6. An arc piece 31 is installed on the outer side of the fixed cylinder 29, and the arc piece 31 is slidably connected to the rotating cylinder 6. The insertion rod 28 is slidably connected to the fixed cylinder 29, and a seal is set at the intersection of the two. The other end of the insertion rod 28 is fixedly connected to the push rod 16 close to it, and the fixed plate 30 is fixedly connected to the insertion rod 28. The two ends of the spring are fixedly connected to the fixed cylinder 29 and the fixed plate 30 respectively, and the spring is in a compressed state.

[0024] Working principle: First of all, it should be explained that the rotating wheel 20, the guide wheel 21 and the rotating drum 6 can all rotate independently. When the rotating wheel 20 needs to rotate, the driving motor A19 drives the rotating rod 13 to rotate. The rotating rod 13 is fixed to the rotating wheel 20, so the rotating rod 13 can drive the rotating wheel 20 to rotate. When the rotating wheel 20 rotates, it is used to control the rotation of the combined pad 14. This is because the rotating wheel 20 can drive a number of push-pull plates 23 to rotate, and the push-pull plates 23 drive the support rods 15 to rotate, and the combined pad 14 is driven by the support rods 15 to rotate. When the combined pad 14 rotates, it can also drive the spring assembly to rotate. When the guide wheel 21 needs to rotate, the driving motor B drives the gear A to rotate, and the gear A drives the gear B2 6 rotates, gear B26 drives guide wheel 21 to rotate, arc groove 24 inside guide wheel 21 can push fixed column 22 to move, fixed column 22 drives push-pull plate 23 to move, because push-pull plate 23 is slidably connected with the slide groove inside rotating wheel 20, and when the position of rotating wheel 20 remains unchanged, push-pull plate 23 can drive support rod 15 to move toward the direction close to rotating rod 13, when rotating drum 6 needs to rotate, one of rotating disks 12 is connected with external motor, and rotating disk 12 is driven to rotate by external motor, and rotating disk 12 is fixed to rotating drum 6, so that rotation of rotating drum 6 can be realized, and rotating wheel 20, guide wheel 21 and rotating drum 6 can also work together, laying foundation for subsequent test of concrete air content.

[0025] Next, by rotating the drum 6, the opening 9 of the drum 6 is rotated to a position corresponding to the feed hopper 27, and then the concrete to be tested is put into the feed hopper 27, and the concrete in the feed hopper 27 enters the opening 9, and then enters the drum 6. At this time, the several arc pads A141 of the combined pad 14 should be kept in contact with the inner wall of the drum 6, and several closed spaces are formed between the combined pad 14 and the drum 6, and the concrete in the opening 9 enters a space close to it, and then the rotation of the wheel 20 can be controlled to realize the rotation of the combined pad 14. During the uniform rotation of the combined pad 14, the concrete in the opening 9 enters several spaces in turn, so that the feeding between the combined pad 14 and the drum 6 is more uniform; due to the rotating rod 13 It is connected to the driving motor A19, and the rotation of the rotating rod 13 can be limited by the driving motor A19. Then, the position of the rotating rod 13 needs to be kept fixed by the limitation of the driving motor A19. The rotating rod 13 is fixed to the rotating wheel 20, so the position of the rotating wheel 20 can be fixed. Then, the gear A is driven to rotate by the driving motor B, and the gear A drives the gear B26 to rotate. The gear B26 drives the guide wheel 21 to rotate. The arc groove 24 inside the guide wheel 21 can push the fixed column 22 to move, and the fixed column 22 drives the push-pull plate 23 to move. Since the push-pull plate 23 is slidably connected with the sliding groove in the rotating wheel 20, and the position of the rotating wheel 20 remains unchanged, the push-pull plate 23 can drive the support rod 15 to move in the direction close to the rotating rod 13. At this time, the combined pad 14 A gap is created between the arc pad A141 and the rotating drum 6, and this gap enables the concrete in each space to circulate with each other. It should be noted that due to the elastic force of the spring, a thrust is applied to the insertion rod 28, so that the push rod 16 continues to support the arc pad B142 of the combined pad 14, so that the combined pad 14 can maintain a stable star-shaped structure, and then the combined pad 14 is rotated by rotating the wheel 20. The star-shaped structure of the combined pad 14 can stir the concrete, so that the bubbles in the concrete are evenly distributed, which helps to improve the test of the air content of the concrete. After stirring, the combined pad 14 is restored to its original position again. At this time, the combined pad 14 separates the concrete into several closed spaces, and the inclined pad 143 of the combined pad 14 squeezes the concrete. It should be noted that the inclined pad 143 of the combined pad 14 is made of rubber, which can not only make the combined pad 14 shrink as a whole, but also rely on its certain hardness to compact the concrete, and the concrete can be compacted without the need for workers to perform compacting work. Since the uniformity and compaction degree of concrete charging have a great influence on the measurement results, if the charging is uneven, or the compaction is excessive or insufficient, the air bubbles inside the concrete will be unevenly distributed, resulting in the measured air content not being able to truly reflect the actual air content of the concrete. For example, excessive compaction may cause some bubbles to be squeezed out, resulting in a low measured value; insufficient compaction may cause larger pores inside the concrete, resulting in a higher measured value.

[0026] Next, successively increasing air pressures are applied to the three chambers 10 through the three air inlet pipes A18, and then the rotating drum 6 is rotated to direct the opening 9 in the rotating drum 6 toward the chamber 10 with the smallest air pressure. The gas in the chamber 10 enters the space between the combined pad 14 and the rotating drum 6. As the combined pad 14 rotates, pressure is applied to concrete at different positions. Since the concrete is divided into multiple spaces, the detection accuracy of the concrete can be improved. Then, according to the above operation, the opening 9 in the rotating drum 6 is directed toward the remaining two chambers 10 in turn. It should be noted that the air pressure should be increased in turn. It should be noted that chambers of different levels can independently and accurately control and adjust different pressure ranges. For example, the chamber 10 with the highest pressure can perform preliminary measurement and balance of larger bubbles in the concrete at a relatively high pressure, so that the larger bubbles can be detected. Some larger bubbles are released and participate in pressure balance; one of the chambers 10 is at a lower pressure and can more attentively measure the effect of medium-sized bubbles on pressure; chamber 10 is at an even lower pressure and specifically measures tiny bubbles. This graded measurement method can more accurately capture the pressure changes caused by bubbles of different sizes, and can more accurately measure the air content in concrete than an air pump that simply switches three pressures. During the measurement process, pressure fluctuations may occur when the air pump switches pressure, and the multi-stage chamber structure can form a relatively stable pressure environment in each chamber. Each chamber has an independent pressure regulation and balancing system. When the air pump provides pressure to the next chamber, the pressure of the previous chamber will not be disturbed, thereby reducing the impact of pressure fluctuations on the measurement results and improving the accuracy of the measurement.

[0027] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A device for testing the air content of concrete under constant temperature and humidity, comprising a bowl body (1) and a bowl cover (2), characterized in that: The bowl body (1) is provided with a constant temperature chamber (3), a cavity (4) and a pressurizing chamber (5); a rotating drum (6) for storing concrete is rotatably mounted on the inner side of the bowl body (1); an air inlet (7) and an air outlet (8) are provided in the cavity (4); an opening (9) is provided inside the rotating drum (6); the pressurizing chamber (5) includes chambers (10) with successively increasing air pressures; each chamber (10) is provided with an exhaust port (11) for conveying gas to the opening (9); both ends of the rotating drum (6) are fixedly connected with a rotating disk (12); a rotating rod (13) for rotating is installed between the two rotating disks (12); and a transmission mechanism is installed on the outer side of the rotating rod (13); A combined pad (14) having a star-shaped structure is provided inside the rotating drum (6). The combined pad (14) comprises a plurality of arc pads A (141), a plurality of arc pads B (142) and a plurality of inclined pads (143). The arc pads A (141) are in contact with the rotating drum (6). A support rod (15) is fixedly connected to the arc surface of each arc pad A (141) close to the rotating rod (13). When the rotating rod (13) rotates, the support rod (15) is controlled to move by a transmission mechanism. A push rod (16) is fixedly connected to the arc surface of each arc pad B (142) away from the rotating rod (13). The push rod (16) presses the arc pad B (142) in a direction close to the rotating rod (13) through a spring assembly.

2. The device for testing the air content of concrete under constant temperature and humidity according to claim 1, characterized in that: The outside of the constant temperature chamber (3) is connected to an air inlet pipe B (17) for supplying warm air to the constant temperature chamber (3), and a valve is installed at one end of the air inlet pipe B (17).

3. The device for testing the air content of concrete under constant temperature and humidity according to claim 1, characterized in that: The outside of each chamber (10) is connected to an air intake pipe A (18), and a valve is installed at one end of each air intake pipe A (18).

4. The device for testing the air content of concrete under constant temperature and humidity according to claim 1, characterized in that: A driving motor A (19) is installed inside one of the rotating disks (12), and an output end of the driving motor A (19) is fixedly connected to the rotating rod (13). One end of the other rotating disk (12) is connected to an external motor.

5. The device for testing the air content of concrete under constant temperature and humidity according to claim 1, characterized in that: The transmission mechanism comprises a rotating wheel (20), a guide wheel (21) for rotation, a plurality of fixed columns (22) and a plurality of push-pull plates (23); the rotating wheel (20) is fixedly connected to the rotating rod (13); a plurality of slide grooves are arranged inside the rotating wheel (20); each push-pull plate (23) is slidably connected to a slide groove adjacent to it and is fixedly connected to a support rod (15) adjacent to it; the guide wheel (21) is rotatably connected to the rotating rod (13); a plurality of arc grooves (24) are arranged inside the guide wheel (21); each fixed column (22) is slidably connected to a arc groove (24) adjacent to it and is fixedly connected to a push-pull plate (23) adjacent to it.

6. The device for testing the air content of concrete under constant temperature and humidity according to claim 5, characterized in that: The outer side of the rotating rod (13) is fixedly connected to a mounting plate (25), a driving motor B is fixedly mounted on one side of the mounting plate (25), an output end of the driving motor B is fixed to a gear B (26), a gear A is rotatably connected to the outer side of the rotating rod (13), gear A is fixedly connected to one of the guide wheels (21), an outer surface of the gear A is meshingly connected to the gear B (26), and the output end of the driving motor B is fixedly connected to the gear B (26).

7. The device for testing the air content of concrete under constant temperature and humidity according to claim 1, characterized in that: A feed hopper (27) is fixedly connected to the cavity (4), and a sealing cover is provided at the inlet of the feed hopper (27). When the opening (9) moves to a position corresponding to the feed hopper (27), concrete is transported into the opening (9).

8. The device for testing the air content of concrete under constant temperature and humidity according to claim 1, characterized in that: The upper surface and the bottom surface of the combined pad (14) are in close contact with the two rotating disks (12) respectively.

9. The device for testing the air content of concrete under constant temperature and humidity according to claim 1, characterized in that: The arc pad A (141) and the arc pad B (142) are both made of silicone material, and the tilt pad (143) is made of rubber material.

10. The device for testing the air content of concrete under constant temperature and humidity according to claim 1, characterized in that: The spring assembly comprises a spring, an insert rod (28), a fixed cylinder (29) and a fixed plate (30); the fixed cylinder (29) is slidably connected to the inner wall of the rotating cylinder (6); an arc-shaped sheet (31) is installed on the outer side of the fixed cylinder (29); the arc-shaped sheet (31) is slidably connected to the rotating cylinder (6); the insert rod (28) is slidably connected to the fixed cylinder (29); a sealing is arranged at the intersection of the two; the other end of the insert rod (28) is fixedly connected to a push rod (16) adjacent to the insert rod (28); the fixed plate (30) is fixedly connected to the insert rod (28); the two ends of the spring are respectively fixedly connected to the fixed cylinder (29) and the fixed plate (30); and the spring is in a compressed state.

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