Soil resistance detection device

Abstract

The invention provides a soil resistance detection device. The soil resistance detection device comprises a main cavity, an electrode system and a measurement host, the main cavity comprises a base, a cylinder body, a vibration mechanism, a cup body and a top cover. The vibration mechanism is in transmission fit with the cup body to conduct vibration compaction on the soil. The top cover is provided with a top pressing plate connected with a telescopic rod, and a volume-adjustable detection cavity is defined by the top pressing plate and the cup body. An exhaust mechanism capable of being inserted into soil and a telescopic mechanism for controlling the exhaust mechanism to move are arranged on the top pressing plate. During working, the exhaust mechanism is inserted into the bottom of soil and moves upwards synchronously along with downward pressing of the top pressing plate, and the bottom of the exhaust mechanism is flush with the bottom face of the top pressing plate when compaction is completed. The device integrates the functions of vibration compaction, synchronous exhaust and resistance measurement, can effectively control the soil compactness, exhaust internal air, remarkably improve the measurement precision and repeatability and simplify the operation process, and is suitable for soil electrical property detection in the fields of agriculture, environment, geology and the like.

Description

Technical Field

[0001] This invention relates to the field of soil testing equipment technology, and in particular to a soil resistance testing device. Background Technology

[0002] Soil resistivity is an important parameter for evaluating soil conductivity and has significant applications in agricultural soil improvement, grounding engineering design, geological disaster monitoring, and environmental geophysical exploration. Accurate soil resistivity measurements are also crucial for soil salinity assessment, moisture monitoring, and pollutant migration analysis.

[0003] Currently, common methods for measuring soil resistivity mainly include the traditional four-electrode method and indoor soil sampling methods. Traditional field four-electrode methods are significantly affected by factors such as soil heterogeneity, temperature and humidity variations, and electrode contact conditions, often resulting in large discrepancies in the measurement results. Indoor soil sampling methods typically require sampling, placing the soil sample in a fixed container, and then measuring by inserting electrodes. However, after sampling, the soil is prone to loosening, incorporating air and resulting in different physical states and densities before and after sampling, which can easily lead to measurement errors. Furthermore, existing indoor measurement devices have the following significant shortcomings:

[0004] Soil compaction control is a key issue: the compaction of soil within the container significantly affects resistivity measurement results. Existing devices mostly rely on manual filling and compaction, which is difficult to control quickly and accurately, leading to poor comparability of measurement results.

[0005] Influence of air within the soil: Air trapped between soil particles forms insulating bubbles, significantly increasing electrical resistance measurements. Current technology lacks effective methods for venting this air, leading to inflated and unstable measurements. Summary of the Invention

[0006] In view of the shortcomings of the existing technology, the present invention provides a soil resistance detection device to solve the technical problems of inaccurate soil compaction control, internal air affecting measurement accuracy, and cumbersome operation procedures.

[0007] According to an embodiment of the present invention, a soil resistivity detection device is provided, comprising a main cavity, an electrode system, and a measuring host. The main cavity includes a base, a cylinder fixed on the base, a vibration mechanism fixed to the bottom of the cylinder, a cup movably disposed within the cylinder for loading soil, and a top cover detachably connected to the cylinder. The vibration mechanism is driven by the cup. The top cover is provided with a telescopic rod and connected to a top pressure plate that can extend into the cup. The top pressure plate and the cup together form a detection cavity with adjustable volume. The top pressure plate is also movably provided with an exhaust mechanism that can be inserted into the soil. The top pressure plate is also provided with a telescopic mechanism connected to the exhaust mechanism and capable of driving it to move axially along the cylinder. When the top pressure plate contacts the soil surface, the exhaust mechanism is inserted into the bottom of the soil. As the top pressure plate presses down, the exhaust mechanism moves upward to a stop height set by the top pressure plate, so that the bottom end of the exhaust mechanism is at the same level as the bottom surface of the top pressure plate.

[0008] Preferably, a cage-shaped bracket is fixedly provided on the top of the top pressure plate and connected to the telescopic rod. The exhaust mechanism is located inside the bracket and includes multiple exhaust pipes that penetrate the top pressure plate and are parallel to the axis of the cylinder, and a suction pump connected to the exhaust pipes. The multiple exhaust pipes are evenly distributed around the top pressure plate.

[0009] More preferably, the telescopic mechanism is fixed inside the bracket and its telescopic arm is connected to a lifting plate facing upwards. The air pump is fixed to the top of the lifting plate. The top of the exhaust pipe passes through the lifting plate upwards and is connected to the air pump. The exhaust pipe is fixedly connected to the lifting plate.

[0010] More preferably, the bottom of the exhaust pipe is closed and pointed, and its edge is provided with multiple sets of inwardly recessed strip-shaped air guide grooves extending along its axial direction. The bottom of the strip-shaped air guide grooves is provided with multiple evenly distributed air holes.

[0011] More preferably, the vibration mechanism includes a base fixed on the base, a vibration generator disposed in the base, and a vertical transmission rod connected to the vibration generator. The base is provided with a guide hole, and the bottom of the cup is provided with an abutment hole. The transmission rod passes through the guide hole and extends into the abutment hole to abut against it.

[0012] More preferably, the base has a chamber, the bottom of the chamber is connected to a transmission plate via an elastic element, the vibration generator is mounted on the transmission plate and can drive it to vibrate, and the transmission rod is connected to the transmission plate.

[0013] More preferably, the top of the transmission rod is provided with a magnetic head, and the contact hole is provided with a magnetic block that cooperates with the magnetic head.

[0014] More preferably, the bottom of the cup body is provided with an assembly groove that matches the shape of the base.

[0015] More preferably, a distance sensor is provided between the bottom of the cup body and the base, located on one side of the assembly slot, and the telescopic rod is a servo electric push rod.

[0016] In a further preferred embodiment, pull rings for removing the cup are fixedly provided on both sides of the top of the cup body, and an annular slot for cooperating with the cylindrical body is provided at the bottom of the top cover. The outer side of the top cover is connected to the outer side of the cylindrical body by a snap fastener.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] A top pressure plate driven by a servo-driven electric actuator forms the main pressure source. The servo-driven electric actuator, acting as the actuator, can precisely control the displacement, speed, and even the maintained pressure according to a preset program, and its bottom integrates a vibration mechanism. This mechanism transmits vibration directly to the cup body via a transmission rod. The vibration causes soil particles to overcome friction and rearrange into a denser, more uniform state. This dual structure, combining "static top pressure for volume control" and "dynamic vibration for compaction," allows the soil to reach the target volume more quickly, significantly improving the accuracy of compaction control.

[0019] Multiple pointed venting pipes are pre-inserted to a depth close to the bottom of the pressure plate when it contacts the soil surface, and are evenly distributed circumferentially along the pressure plate. This design ensures that venting points cover deep areas of the soil and are evenly distributed from the start of compaction. The telescopic mechanism connecting the venting pipes works in conjunction with the downward movement of the pressure plate. As the pressure plate presses down and the soil is compressed and thinned, the telescopic mechanism controls the venting pipes to retract upwards synchronously. By controlling the relative speed of the venting pipes and the pressure plate, the effective venting section of the venting pipes is always located in the currently compressed soil layer, allowing for real-time removal of air released due to particle compression. This "tracking" venting method is far more efficient than fixed-depth venting. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the main structure of a soil resistance detection device according to the present invention.

[0021] Figure 2 This is a partial enlarged structural diagram of a soil resistance detection device according to the present invention.

[0022] Figure 3 This is a partial enlarged structural diagram of a soil resistance detection device according to the present invention.

[0023] Figure 4 This is a magnified schematic diagram of a portion B of the soil resistance detection device of the present invention.

[0024] In the above attached figures: 1. Base; 2. Cylinder; 3. Detection chamber; 4. Vibration mechanism; 401. Base; 402. Vibration generator; 403. Transmission rod; 404. Chamber; 405. Elastic element; 406. Transmission plate; 407. Magnetic head; 408. Guide hole; 5. Cup body; 501. Contact hole; 502. Magnetic block; 503. Assembly slot; 504. Distance sensor; 505. Pull ring; 6. Top cover; 601. Telescopic rod; 602. Top pressure plate; 603. Buckle; 604. Bracket; 605. Annular slot; 7. Exhaust mechanism; 701. Exhaust pipe; 702. Air pump; 703. Air guide groove; 704. Air hole; 8. Telescopic mechanism; 801. Lifting plate. Detailed Implementation

[0025] The technical solutions of the present invention will be further described below with reference to the accompanying drawings and embodiments.

[0026] This invention provides an embodiment, such as... Figure 1 As shown, a soil resistivity testing device includes a main cavity, an electrode system, and a measuring host. The measuring host is equipped with a control system. The main cavity includes a base 1, a cylinder 2 fixed to the base 1, a vibration mechanism 4 fixed to the bottom of the cylinder 2, a cup 5 movably disposed within the cylinder 2 for loading soil, and a top cover 6 detachably connected to the cylinder 2. The cylinder 2 is preferably made of transparent or semi-transparent engineering plastic to facilitate observation of the internal soil condition. The base 1 is made of metal, providing good stability and vibration resistance. The cup 5 is made of insulating material with a smooth inner wall to reduce soil adhesion, and its side wall has pre-set electrode insertion holes.

[0027] The vibration mechanism 4 is driven by the cup body 5 and can vibrate and compact the soil inside the cup body 5. The top cover 6 is provided with a telescopic rod 601 and connected to a top pressure plate 602 that can extend into the cup body 5. The top cover 6 is provided with a movable hole. In the initial state, the top pressure plate 602 is located in the movable hole. The top pressure plate 602 and the cup body 5 together form a detection cavity 3 with adjustable volume. The diameter of the top pressure plate 602 is slightly smaller than the inner diameter of the cup body 5, so that it can move up and down freely while maintaining a small gap with the inner wall of the cup body 5 to prevent the soil from being squeezed out laterally.

[0028] The top pressure plate 602 is also movably provided with an exhaust mechanism 7 that can be inserted into the soil. The top pressure plate 602 is also provided with a telescopic mechanism 8 that is connected to the exhaust mechanism 7 and can drive it to move along the axial direction of the cylinder 2. The telescopic mechanism 8 is preferably a small electric push rod or cylinder. When the top pressure plate 602 contacts the soil surface, the exhaust mechanism 7 is inserted into the bottom of the soil. As the top pressure plate 602 is pressed down, the exhaust mechanism 7 moves upward to the stop height set by the top pressure plate 602, so that the bottom end of the exhaust mechanism 7 is at the same level as the bottom surface of the top pressure plate 602.

[0029] To protect the exhaust mechanism 7 and the telescopic mechanism 8, in a further embodiment, a cage-shaped bracket 604 is fixedly provided on the top of the top pressure plate 602 and connected to the telescopic rod 601. The exhaust mechanism 7 is located inside the bracket 604 and includes multiple exhaust pipes 701 that penetrate the top pressure plate 602 and are parallel to the axis of the cylinder 2, and an air pump 702 connected to the exhaust pipes 701. The air pump 702 can generate sufficient negative pressure to extract air from the soil. The multiple exhaust pipes 701 are evenly distributed around the top pressure plate 602. Four exhaust pipes 701 are provided to ensure uniform exhaust.

[0030] The outer surface of the exhaust pipe 701 is coated with a hydrophobic and oleophobic coating to reduce soil adhesion and facilitate cleaning. The inner wall of the pipe is smooth to reduce airflow resistance.

[0031] The air pump 702 is equipped with a pressure sensor to monitor negative pressure changes during the exhaust process. The control system judges the exhaust effect and soil condition based on the negative pressure changes. For example, when the negative pressure reaches a stable value and remains so for a period of time, it indicates that the air inside the soil has been basically expelled, and the process can proceed to the next stage.

[0032] Specifically, such as Figure 1 , Figure 3 As shown, the telescopic mechanism 8 is fixed inside the bracket 604 and its telescopic arm is connected to the lifting plate 801 facing upward. The air pump 702 is fixed to the top of the lifting plate 801. The top of the exhaust pipe 701 passes through the lifting plate 801 and is connected to the air pump 702. The exhaust pipe 701 is fixedly connected to the lifting plate 801. When the telescopic mechanism 8 retracts, it drives the lifting plate 801, the air pump 702 and the exhaust pipe 701 to move upward together, so that the exhaust pipe 701 retracts upward relative to the top pressure plate 602.

[0033] To facilitate the insertion of the venting pipe 701 into the soil, in a further embodiment, such as... Figure 4As shown, the bottom of the exhaust pipe 701 is closed and pointed, and its edge is provided with multiple sets of inwardly recessed strip-shaped air guide grooves 703 extending along its axial direction. The bottom of the strip-shaped air guide grooves 703 is provided with multiple evenly distributed air holes 704. This structure can reduce resistance when inserted into the soil, and at the same time, it can collect air inside the soil through the air guide grooves 703 and discharge it into the pipe through the air holes 704.

[0034] Specifically, such as Figure 1 , Figure 2 As shown, the vibration mechanism 4 includes a base 401 fixed on the base 1, a vibration generator 402 disposed in the base 401, and a vertical transmission rod 403 connected to the vibration generator 402. The vibration generator 402 is preferably an electromagnetic vibrator, whose vibration frequency and amplitude are adjustable to adapt to the compaction requirements of different soil types. The base 401 is provided with a guide hole 408, and the bottom of the cup body 5 is provided with an abutment hole 501. The transmission rod 403 passes through the guide hole 408 and extends into the abutment hole 501 to abut against it, transmitting vibration to the cup body 5.

[0035] To prevent vibration from being transmitted to the base 1, in a further embodiment, the base 401 is provided with a chamber 404, and the bottom of the chamber 404 is connected to a transmission plate 406 via an elastic element 405. The elastic element 405 is preferably a helical spring or a rubber damping pad, which can buffer vibration and prevent vibration from being transmitted to the base 1. The vibration generator 402 is disposed on the transmission plate 406 and can drive it to vibrate. The transmission rod 403 is connected to the transmission plate 406. This structure can make the vibration more evenly transmitted to the transmission rod 403, while reducing the impact on the base 1.

[0036] To improve vibration transmission efficiency, in a further embodiment, the top of the transmission rod 403 is provided with a magnetic suction head 407, and the contact hole 501 is provided with a magnetic suction block 502 that cooperates with the magnetic suction head 407. This magnetic connection method not only ensures the effectiveness of vibration transmission but also facilitates the picking up and putting down of the cup body 5. The magnetic suction head 407 and the magnetic suction block 502 are preferably made of neodymium iron boron permanent magnet material, which has high magnetic attraction force.

[0037] To facilitate the quick installation of the cup body 5, in a further embodiment, the bottom of the cup body 5 is provided with an assembly groove 503 that matches the shape of the base 401. The inner wall of the assembly groove 503 is provided with a guide protrusion that cooperates with the guide groove on the outer wall of the base 401 to ensure that the cup body 5 can be automatically aligned when placed.

[0038] To facilitate control of the precise top pressure plate 602, in a further embodiment, a distance sensor 504 is provided between the bottom of the cup body 5 and the base 1, located on one side of the assembly groove 503. The distance sensor 504 is preferably a laser rangefinder or an ultrasonic sensor, capable of measuring the distance change between the bottom of the cup body 5 and the base 1. By monitoring this distance change and the travel distance of the telescopic rod 601, the degree of soil compaction can be assessed. The telescopic rod 601 is a servo-electric actuator, whose travel and thrust can be precisely controlled.

[0039] Meanwhile, since the cup body 5 will experience slight vibrations during vibration, the soil compaction and vibration state can be assessed by monitoring the range of this distance change. The control system adjusts the operating parameters of the vibration generator 402 based on the feedback signal from the distance sensor 504 to achieve adaptive vibration control. For example, when a large vibration amplitude is detected in the cup body 5, it indicates that the soil is in a relatively loose state, and the vibration intensity can be appropriately increased; when the vibration amplitude decreases to a stable range, it indicates that the soil is basically compacted, and the vibration intensity can be reduced or the process can be switched to the pressure-holding stage.

[0040] To facilitate the removal of the cup body 5, in a further embodiment, pull rings 505 for removing the cup body 5 are fixed on both sides of the top. The bottom of the top cover 6 is provided with an annular slot 605 that mates with the cylindrical body 2. The annular slot 605 and the top of the cylindrical body 2 are interference-fitted to ensure that the top cover 6 is quickly installed in place and that the structure between the top cover 6 and the cylindrical body 2 is stable. The outer side of the top cover 6 is connected to the outer side of the cylindrical body 2 by a buckle 603.

[0041] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A soil resistivity detection device, comprising a main cavity, an electrode system, and a measuring host, characterized in that: The main cavity includes a base (1), a cylinder (2) fixed on the base (1), a vibration mechanism (4) fixed at the bottom of the cylinder (2), a cup (5) movably disposed in the cylinder (2) for loading soil, and a top cover (6) detachably connected to the cylinder (2). The vibration mechanism (4) is driven by the cup (5). The top cover (6) is provided with a telescopic rod (601) and connected to a top pressure plate (602) that can extend into the cup (5). The top pressure plate (602) and the cup (5) together form a detection cavity (3) with adjustable volume. The top pressure plate (602) is also movably provided with an exhaust mechanism (7) that can be inserted into the soil. The top pressure plate (602) is also provided with a telescopic mechanism (8) that is connected to the exhaust mechanism (7) and can drive it to move along the axial direction of the cylinder (2). When the top pressure plate (602) contacts the soil surface, the exhaust mechanism (7) is inserted into the bottom of the soil. As the top pressure plate (602) is pressed down, the exhaust mechanism (7) moves upward to the stop height set by the top pressure plate (602), so that the bottom end of the exhaust mechanism (7) is at the same level as the bottom surface of the top pressure plate (602).

2. The soil resistivity detection device according to claim 1, characterized in that, The top of the top pressure plate (602) is fixedly provided with a cage-shaped bracket (604) and connected to the telescopic rod (601). The exhaust mechanism (7) is located inside the bracket (604) and includes multiple exhaust pipes (701) that pass through the top pressure plate (602) and are parallel to the axis of the cylinder (2), and a vacuum pump (702) connected to the exhaust pipes (701). The multiple exhaust pipes (701) are evenly distributed around the top pressure plate (602).

3. The soil resistivity detection device according to claim 2, characterized in that, The telescopic mechanism (8) is fixed inside the bracket (604) and its telescopic arm is connected to the lifting plate (801) facing upward. The air pump (702) is fixed on the top of the lifting plate (801). The top of the exhaust pipe (701) passes through the lifting plate (801) upward and is connected to the air pump (702). The exhaust pipe (701) is fixedly connected to the lifting plate (801).

4. A soil resistivity detection device according to claim 2, characterized in that, The bottom of the exhaust pipe (701) is closed and pointed, and its edge is provided with multiple sets of inwardly recessed strip-shaped air guide grooves (703) extending along its axial direction. The bottom of the strip-shaped air guide grooves (703) is provided with multiple evenly distributed air holes (704).

5. A soil resistivity detection device according to claim 1, characterized in that, The vibration mechanism (4) includes a base (401) fixed on the base (1), a vibration generator (402) disposed in the base (401), and a vertical transmission rod (403) connected to the vibration generator (402). The base (401) is provided with a guide hole (408), and the bottom of the cup body (5) is provided with an abutment hole (501). The transmission rod (403) passes through the guide hole (408) and extends into the abutment hole (501) to abut against it.

6. A soil resistivity detection device according to claim 5, characterized in that, The base (401) has a chamber (404) inside. The bottom of the chamber (404) is connected to a transmission plate (406) through an elastic element (405). The vibration generator (402) is mounted on the transmission plate (406) and can drive it to vibrate. The transmission rod (403) is connected to the transmission plate (406).

7. A soil resistivity detection device according to claim 5, characterized in that, The transmission rod (403) is provided with a magnetic head (407) at the top, and a magnetic block (502) that cooperates with the magnetic head (407) is provided in the contact hole (501).

8. A soil resistivity detection device according to claim 5, characterized in that, The bottom of the cup body (5) is provided with an assembly groove (503) that matches the shape of the base (401).

9. A soil resistivity detection device according to claim 8, characterized in that, A distance sensor (504) is provided between the bottom of the cup body (5) and the base (1) on one side of the assembly groove (503), and the telescopic rod (601) is a servo electric push rod.

10. A soil resistivity detection device according to claim 1, characterized in that, The cup body (5) has pull rings (505) fixed on both sides of the top for taking it out, and the bottom of the top cover (6) has an annular slot (605) that cooperates with the cylinder (2). The outer side of the top cover (6) is connected to the outer side of the cylinder (2) by a buckle (603).

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