Artificial forest soil nutrient monitoring sensor

Abstract

The invention relates to the technical field of seedling cultivation, in particular to a man-made forest soil nutrient monitoring sensor which comprises a sensor body, the outer side of the sensor body is sleeved with a guide pipe, and the sensing end of the sensor body can extend out of the guide pipe; the outer wall of the non-induction end of the sensor body is fixedly connected with a sliding sleeve, the outer wall of the sliding sleeve is fixedly connected with a sliding seat, the sliding seat penetrates through the linear sliding groove and extends to the radial outer side of the guide pipe, and an inclined extrusion part is formed at the outer end of the sliding seat; the inclined surface of the inclined extrusion part downwards and obliquely extends towards the non-sensing end of the sensor body; a hole is formed in soil in advance through the drill bushing, a clean and stable deep detection space is provided for detection, the sensing end of the sensor does not participate in deep hole prefabrication, the sensing end extends out to achieve deep soil detection only when the sensing end reaches the detection space at the bottom of the formed hole, and the service life is prolonged.

Description

Technical Field

[0001] This invention relates to the field of seedling cultivation technology, and in particular to a sensor for monitoring soil nutrients in plantations. Background Technology

[0002] Masson pine is an important fast-growing timber species in southern my country, with a wide range and large area of ​​plantation cultivation. Precise supply of soil nutrients is crucial to ensuring the timber yield and quality of Masson pine. Due to the characteristics of its well-developed taproot system and deep root penetration, the nitrogen, phosphorus, potassium, and trace element content in the deeper soil layers directly determines its growth. Therefore, it is necessary to conduct targeted monitoring of the soil at deeper levels. Currently, soil nutrient monitoring in Masson pine plantations mostly uses the rod-type sensor detection method. This involves inserting a rod-mounted sensor vertically into the deep soil layer to directly obtain data. Compared to traditional sampling and testing, this method can quickly reflect the soil fertility status in the taproot distribution area and has become an important means of managing Masson pine plantations.

[0003] However, most Masson pine plantations are distributed in mountainous and hilly areas, where the soil has a high sand and gravel content, the soil layer is compact, and the root system is intertwined. The existing simple direct insertion structure of the pole-mounted sensor has obvious defects: when the sensor is inserted, it is easy to rub and collide with sand, gravel, and dead roots, resulting in severe friction at the sensing end and significant damage. Moreover, when the insertion stroke is large, the stress is continuously concentrated on the sensing end, affecting the service life of the sensing end. Summary of the Invention

[0004] To address the aforementioned problems, this invention provides a soil nutrient monitoring sensor for plantations, comprising a sensor body, a guide tube sleeved on the outer side of the sensor body, and the sensing end of the sensor body extending to the outside of the guide tube; a sliding sleeve fixedly connected to the outer wall of the non-sensing end of the sensor body, the sliding sleeve slidingly engaging with the inner wall of the guide tube; a straight groove formed on the guide tube, a sliding seat fixedly connected to the outer wall of the sliding sleeve, the sliding seat passing through the straight groove and extending radially outward of the guide tube, an inclined pressing portion formed at the outer end of the sliding seat, the inclined surface of the inclined pressing portion extending downward towards the non-sensing end of the sensor body; a tension spring provided inside the guide tube, one end of the tension spring connected to the non-sensing end of the sensor body, and the other end connected to the end of the guide tube cavity; an assembly hole provided at the end of the guide tube away from the sensing end of the sensor body, the assembly hole for rotatably connecting with a torsion spring hinge on an external rod, allowing the guide tube to rotate and switch between a retracted parallel position and a detection unfolded position relative to the external rod under the action of the torsion spring hinge.

[0005] When the guide tube enters the external drill sleeve along with the external rod and is constrained by the drill sleeve, the guide tube is in a retracted state parallel to the external rod. The tension spring pulls the sensor body into the guide tube for protection. When the guide tube extends out of the drill sleeve along with the external rod and is released from constraint, the guide tube rotates to an unfolded state at a set angle with the external rod under the action of the torsion spring hinge. The inclined pressing part of the slide is pressed by the pressing protrusion at the lower end of the drill sleeve, driving the slide and the slide sleeve to drive the sensor body to extend linearly relative to the guide tube, so that the sensing end of the sensor body presses against the inner wall of the soil to achieve detection.

[0006] Preferably, the structure of the torsion spring hinge shaft is as follows: the guide tube and the external rod are connected by a hinge shaft, a torsion spring is sleeved on the hinge shaft, one free end of the torsion spring is abutted and connected to the rotating end of the guide tube, and the other free end is abutted and connected to the external rod.

[0007] Preferably, the guide tube is arranged perpendicular or approximately perpendicular to the external rod when in the unfolded position.

[0008] Preferably, the external rod is a damping rod, and a damping sleeve is fixed inside the drill sleeve to form a damping sliding fit with the external rod. A drill sleeve for pre-drilling holes in the soil is sleeved on the outside of the external rod. The lower end of the drill sleeve is provided with a pressing protrusion for cooperating with the inclined pressing part. The pressing protrusion is circular or arc-shaped.

[0009] Preferably, the top end of the external rod extends to the outer side of the top end of the drill sleeve, and a limiting block is fixedly connected to the external rod at a position on the outer side of the top end of the drill sleeve.

[0010] Preferably, when the tension spring is in its normal state, it pulls the sensor body into the guide tube, causing the sensing end of the sensor body to retract into the guide tube.

[0011] Preferably, the linear groove extends axially along the guide tube, and the axial movement stroke of the slide block along the linear groove is consistent with the extension stroke of the sensing end of the sensor body.

[0012] Preferably, the sensor body, sliding sleeve, guide tube, slide base and tension spring together constitute a retractable protective sensing assembly, and the mounting hole, hinge shaft, torsion spring and external rods together constitute an unfolding and retracting drive mechanism.

[0013] The advantages of this invention compared to the prior art are:

[0014] This invention houses the sensor body within a guide tube. During detection, a tension spring within the guide tube automatically extends the sensing end when compressed by external force, and automatically retracts after detection when the external force is released. During detection, the guide tube unfolds to an optimal angle perpendicular or nearly perpendicular to the external rod under the action of a torsion spring. The inclined compression part of the slide engages with the compression protrusion on the carrier, converting the axial compression force into a linear thrust, driving the sensing end of the sensor body to be forcibly pressed against the inner wall of the deep soil hole, achieving close contact with the deep soil of *Pinus massoniana*, ensuring both safe use and detection accuracy. During detection, a hole is pre-drilled in the soil using a drill sleeve, providing a clean and stable deep detection space. The sensor's sensing end does not participate in the deep hole pre-drilling; it only extends to perform deep soil detection when it reaches the bottom of the drilled hole, avoiding excessive wear on the sensing end and improving its service life. After the test is completed, the external rod is pulled back, and the wall of the guide tube is squeezed by the bottom of the drill sleeve and rotated to be parallel to the external rod. The tension spring simultaneously pulls the sensor body back into the guide tube and stores it together in the drill sleeve for safe storage. Attached Figure Description

[0015] Figure 1 A schematic diagram of the front view of a soil nutrient monitoring sensor for artificial forests provided for an embodiment of the present invention;

[0016] Figure 2 A top view schematic diagram of a soil nutrient monitoring sensor for artificial forests provided for an embodiment of the present invention;

[0017] Figure 3 A schematic diagram of a disassembled soil nutrient monitoring sensor for an artificial forest, provided for an embodiment of the present invention;

[0018] Figure 4 A schematic diagram illustrating the principle of a plantation soil nutrient monitoring sensor installed on an external pole and used in a drilling sleeve, as provided in this embodiment of the invention.

[0019] Figure 5 A soil nutrient monitoring sensor for artificial forests provided for embodiments of the present invention consists of... Figure 4 An enlarged schematic diagram of part A is shown.

[0020] In the figure: 1. Sensor body; 2. Guide tube; 3. Sliding sleeve; 4. Sliding base; 5. Inclined extrusion part; 6. Linear slide groove; 7. Tension spring; 8. Assembly hole; 9. Torsion spring hinge shaft; 10. External rod; 11. Drill sleeve; 12. Extrusion protrusion; 13. Limiting block; 14. Damping sleeve. Detailed Implementation

[0021] The above and other embodiments and advantages of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0022] In one implementation, such as Figures 1-5 As shown:

[0023] This embodiment provides a soil nutrient monitoring sensor for plantations, including a sensor body 1, a guide tube 2 sleeved on the outside of the sensor body 1, and the sensing end of the sensor body 1 extending to the outside of the guide tube 2; a sliding sleeve 3 is fixedly connected to the outer wall of the non-sensing end of the sensor body 1, and the sliding sleeve 3 slides in cooperation with the inner wall of the guide tube 2; a straight groove 6 is provided on the guide tube 2, and a sliding seat 4 is fixedly connected to the outer wall of the sliding sleeve 3, the sliding seat 4 passes through the straight groove 6 and extends to the radially outer side of the guide tube 2, and an inclined pressing part 5 is formed at the outer end of the sliding seat 4, the inclined surface of the inclined pressing part 5 extending downward towards the non-sensing end of the sensor body 1; a tension spring 7 is provided inside the guide tube 2, one end of the tension spring 7 is connected to the non-sensing end of the sensor body 1, and the other end is connected to the end of the cavity of the guide tube 2; an assembly hole 8 is provided at the end of the guide tube 2 away from the sensing end of the sensor body 1, the assembly hole 8 is used to rotately connect with a torsion spring hinge shaft 9 on an external rod 10, so that the guide tube 2 can rotate and switch between a retracted parallel position and a detection unfolded position relative to the external rod 10 under the action of the torsion spring hinge shaft 9.

[0024] The principle of the sensor is briefly described as follows: The sensor has an internal electrochemical sensitive electrode. When the sensing end is pressed against the inner wall of the soil, nutrient ions in the soil (such as ammonium ions NH4+, phosphate ions PO43-, and potassium ions K+) will undergo an electrochemical reaction with the sensitive electrode, generating a weak current signal. After the current signal is processed by the internal signal amplification and filtering modules of the sensor, it is converted into a recognizable electrical signal, and then the nutrient content data is output to the ground terminal through the data transmission line.

[0025] When the guide tube 2 enters the outer drill sleeve along with the external rod 10 and is constrained by the drill sleeve, the guide tube 2 is in a retracted state parallel to the external rod 10. The tension spring 7 pulls the sensor body 1 into the guide to achieve protection. When the guide tube 2 extends out of the bottom end of the drill sleeve along with the external rod 10 and is released from constraint, the guide tube 2 rotates to an unfolded state at a set angle with the external rod 10 under the action of the torsion spring hinge 9. The inclined pressing part 5 of the slide 4 is pressed by the protrusion at the lower end of the drill sleeve 11, driving the slide 4 and the slide sleeve 3 to drive the sensor body 1 to extend in a straight line relative to the guide tube 2, so that the sensing end of the sensor body 1 presses against the inner wall of the soil to achieve detection. The guide tube 2 serves as the mounting carrier for the sensor body 1. The sensor body 1 can be slidably mounted inside the guide tube 2, and the sensing end of the sensor body 1 can extend beyond one end of the guide tube 2. The other end of the guide tube 2 away from the sensing end of the sensor is provided with an assembly hole 8. The assembly hole 8 is used to transfer the guide tube 2 to the external rod 10 (external rod). The external rod 10 serves as a bearing component for insertion into the soil, and is used to drive the guide tube 2 and the sensor body 1 to be inserted together into the deep soil layer of the Masson pine plantation to be detected.

[0026] In the above embodiment, the sensor body 1 is located inside the guide tube 2. The sensor with a protective structure is connected to the external rod 10 via a hinge shaft through the mounting hole 8 at the other end of the guide tube 2. A torsion spring is sleeved on the hinge shaft. One free end of the torsion spring is abutted against the rotating end of the guide tube 2, and the other free end is abutted against the external rod 10. The specific implementation of the torsion spring hinge shaft 9 is clearly defined to ensure the stability and reliability of the guide tube 2 in relation to the unfolding / retraction of the external rod 10. The abutting connection of the torsion spring can provide a continuous and stable rotational driving force. When assembling and using the sensor body 1, a drill sleeve 11 is also required to be sleeved on the outside of the external rod 10 where it is located. The bottom end of the drill sleeve 11 is conical. During the insertion process into the soil, the guide tube 2 drives the sensor body 1 to rotate around the external rod 10, eventually maintaining a parallel state with the external rod 10. At this time, the tension spring 7 inside the guide tube 2 is in a contracted state, pulling the sensor body 1 into the guide tube 2, so that the sensing end of the sensor body 1 is not exposed, thereby achieving preliminary protection for the sensor body 1 and avoiding damage caused by friction and collision between the sensor sensing end and sand, gravel, and dead roots in the soil during the insertion process. When used in conjunction with the external rod 10, a drill sleeve 11 is also fitted on the outside of the external rod 10. The outer wall of the drill sleeve 11 is often equipped with a scale to detect its insertion depth. The drill sleeve 11 adopts a direct insertion type (direct insertion without rotation). In the non-use state, the external rod 10 drives the sensor body 1 and the guide tube 2 to retract together into the inner cavity of the drill sleeve 11, realizing the complete storage and protection of the sensor. In the use state, the drill sleeve 11 is first inserted downward to the set depth to pre-drill a deep hole in the soil. The purpose is to provide a clean and stable detection space for the sensor body 1 to subsequently detect soil nutrients, avoiding direct insertion of the sensor body 1, which would cause soil compaction and changes in nutrient distribution, thereby affecting the detection accuracy.

[0027] After the drill sleeve 11 completes the drilling, it is raised by a preset stroke to leave space at the bottom of the deep hole for sensor detection. Then, the external rod 10 is inserted downwards to push the guide tube 2 and the sensor body 1 into the reserved space. When the external rod 10 retracts the guide tube 2 and the sensor body 1 into the inner cavity of the drill sleeve 11, the guide tube 2, which is sleeved outside the sensor body 1, will be squeezed by the bottom end of the drill sleeve 11 and rotate around the hinge (with torsion spring) at the mounting hole 8 to a state parallel to the external rod 10. At this time, with the pull-back action of the external rod 10, the guide tube 2, together with the sensor body 1 inside it, will be pulled back into the inner cavity of the drill sleeve 11 for storage, achieving comprehensive protection for the sensor in the non-detection state.

[0028] When the external rod 10 is inserted downwards again, pushing the guide tube 2 and the sensor body 1 together into the reserved space at the bottom of the deep hole, the guide tube 2 is released from the constraint of the drill sleeve 11. Under the rotational force of the torsion spring on the hinge shaft at the assembly hole 8, it rotates around the hinge shaft to a position at a set angle (preferably vertical or approximately vertical) with the bottom end of the external rod 10. At the same time, the inclined pressing part 5 at the outer end of the slide block 4 will contact and be pressed against the pre-set pressing protrusion 12 at the lower end of the drill sleeve 11. The inclined pressing part 5 converts the axial pressing force applied by the pressing protrusion 12 into a linear thrust, driving the slide block 4 to move axially along the linear slide groove 6 on the guide tube 2. The slide block 4 simultaneously drives the slide sleeve 3 and the sensor body 1 fixedly connected to it to move linearly away from the assembly hole 8 along the guide tube 2. Finally, the sensing end of the sensor body 1 is pressed against the soil on the inner wall of the deep hole space, and it is in close contact with the soil around the roots of the Masson pine, thus completing the accurate detection of soil nutrients. After the test is completed, the external rod 10 is pulled back, and the wall of the guide tube 2 is squeezed by the bottom of the drill sleeve 11 and rotated to be parallel to the external rod 10. The tension spring 7 simultaneously pulls the sensor body 1 back into the guide tube 2 and stores it together in the drill sleeve 11 for protection and storage.

[0029] The sensor body 1 is located at one end of the guide tube 2, which has an assembly hole 8, allowing it to be rotatably connected to the external rod 10 via a torsion spring hinge shaft. In addition, when used with the drill sleeve 11, three protective features—drill sleeve 11 retraction, guide tube 2 protection, and tension spring 7 retraction—ensure that the sensor body 1 is completely retracted within the drill sleeve 11 and guide tube 2 when not in a detection state (during retraction, insertion, and removal), with the sensing end not exposed. This effectively isolates the sensor body from friction, collision, and corrosion from soil gravel and dead roots, making it suitable for the high gravel content and compact soil environment of Masson pine plantations. This significantly reduces the sensor failure rate, extends the sensor's lifespan, and addresses the pain points of "easily damaged and frequently replaced" in existing sensors used for deep soil insertion, thus reducing monitoring costs. In actual use, multiple sensor bodies 1 can be connected in a circular array to the bottom of the external rod 10 using the same matching structure and installation method. When deployed in a deep hole space, it can detect multiple areas of the soil within the deep hole, improving detection accuracy.

[0030] When in use, the sensor body 1 is driven entirely by a purely mechanical structure, requiring no additional power supply. The expansion / retraction of the guide tube 2 and the extension / retraction of the sensor body 1 can be achieved solely through the relative movement of the drill sleeve 11 and the external rod 10, the rotational force of the torsion spring, and the contraction force of the tension spring 7. The actions are continuous and automatic, requiring no manual intervention and resulting in a low failure rate.

[0031] Moreover, the sensor body 1 has a compact overall structure. When in use, it can be inserted into the deep soil of the Masson pine plantation along with the external rod 10. After the drill sleeve 11 is pre-drilled, the sensor can accurately extend into the reserved space at the bottom of the deep hole to detect and realize deep soil nutrient monitoring. The sensor body 1 only adds conventional components such as guide tube 2, sliding sleeve 3, spring, and hinge shaft to its exterior. The structure is simple and the manufacturing cost is low. The requirements for the structure, shape and assembly of the third-party external rod 10 and drill sleeve 11 are low.

[0032] By pre-drilling holes using the drill sleeve 11, soil compaction and nutrient distribution changes caused by direct insertion into the sensor body 1 are avoided, providing a stable soil environment for detection. During detection, the guide tube 2 is extended to a reasonable angle, and the inclined pressing part 5 of the slide 4 forces the sensor body 1 against the inner wall of the deep hole through compression, ensuring that the sensing end is in close contact with the soil around the Masson pine root system. In addition, this structure is simple, has low manufacturing cost, is easy to mass-produce, and reduces the overall manufacturing cost of the sensor.

[0033] In another embodiment, the structure of the torsion spring hinge shaft 9 is as follows: the guide tube 2 and the external rod 10 are connected by a hinge shaft, a torsion spring is sleeved on the hinge shaft, one free end of the torsion spring is abutted and connected to the rotating end of the guide tube 2, and the other free end is abutted and connected to the external rod 10.

[0034] The commonly used torsion spring hinge 9 mechanical component is applied to the connection position. During assembly, a vertical groove is first opened at the bottom end of the outer rod 10. The hinge portion of the torsion spring hinge 9 is fixed in the vertical groove. The torsion spring is sleeved on the hinge shaft. The rotating end of the guide tube 2 is assembled onto the hinge shaft through the assembly hole 8 to achieve a rotational connection. Then, one free end of the torsion spring is abutted against the rotating end of the guide tube 2, and the other free end is abutted against the outer rod 10. Under normal conditions, the torsion spring releases its elastic force, and one abutting end pushes the guide tube 2 to rotate out of the tight groove and into a position perpendicular to the guide tube 2. When the outer rod 10 is dragged upward along the guide hole of the drill sleeve 11, the tube wall of the guide tube 2 will contact the drill sleeve. When the bottom end of the drill sleeve 11 contacts the drill sleeve 11, it is squeezed by the bottom end of the drill sleeve 11. At this time, the squeezing force overcomes the supporting force of one end of the torsion spring on the guide tube 2, which will cause the guide tube 2 to rotate back into the vertical groove. As the external rod 10 continues to be dragged upward for a certain distance, the guide tube 2 and the sensor body 1 in the tube cavity are pulled back into the drill sleeve 11. The bottom end of the vertical groove does not completely penetrate the bottom end of the external rod 10. Therefore, when the guide tube 2 carries the sensor body 1 back into the vertical groove, even if the sensing end of the sensor body 1 is facing downward, it will be covered by the bottom end of the vertical groove. When the drill sleeve 11 is inserted into the deep hole again, the sensing end of the sensor does not bear the drilling force, which effectively avoids the sensing end being squeezed and worn by the drilling force, and further ensures the detection accuracy of the sensor.

[0035] In another embodiment, the guide tube 2 is set perpendicular or nearly perpendicular to the external rod 10 when it is in the unfolded position, which only requires that the sensing end of the sensor be radially inserted into the soil hole wall.

[0036] In another embodiment, a damping sleeve 14 is fixed inside the drill sleeve 11 to form a damped sliding fit with the external rod 10, thereby improving the fitting accuracy. The lower end of the drill sleeve 11 is provided with a pressing protrusion 12 for cooperating with the inclined pressing part 5. The pressing protrusion 12 is circular or arc-shaped. A positioning port is provided on the damping sleeve 14, and a positioning slide rail is provided on the outer wall of the external rod 10 along its length direction, which is slidably fitted into the positioning port to prevent the external rod 10 from rotating, thereby ensuring that the guide tube 2 at its bottom end is always opposite to the pressing protrusion 12 at the bottom end of the drill sleeve 11.

[0037] When used together, the drill sleeve 11 and the external rod 10 are auxiliary assembly components used for the sensor body 1. Through the damping relationship, the sensor body 1 is pushed into the deep hole space pre-made in the drill sleeve 11 by pushing the external rod 10 along the inner hole of the drill sleeve 11. Only a simple extrusion protrusion 12 needs to be set at the bottom of the drill sleeve 11 to have an extrusion relationship with the inclined extrusion part 5. As the guide tube 2 rotates outward with the sensor body 1, the extrusion protrusion 12 will gradually exert force on the inclined extrusion part from the inclined bottom position to the high position, thereby forcing the sensor body 1 to extend radially along the cavity of the guide tube 2.

[0038] In another embodiment, the top end of the external rod 10 extends to the outer side of the top end of the drill sleeve 11. A limiting block is fixedly connected to the external rod 10 at the position outside the top end of the drill sleeve 11. When the external rod 10 is pushed down to its maximum stroke, the bottom surface of the limiting block 13 falls on the top end of the drill sleeve 11. At this time, the guide tube 2, carrying the sensor body 1, extends out from the bottom end of the drill sleeve 11. At the same time, the rotating end of the guide tube 2 also extends out from the bottom end of the drill sleeve 11. The torsion spring releases its elastic force to drive the guide tube 2, carrying the sensor body 1, from a retracted posture to a radially extended state. The insertion stroke of the external rod is based on the bottom surface of the limiting block 13 falling on the top end of the drill sleeve 11, which is also the marker position for the above-mentioned components to perform detection actions in the deep hole bottom space. The limiting block 13 plays a precise limiting role. Through the mechanical limiting method of "the bottom surface of the limiting block 13 abutting against the top of the drill sleeve 11", the maximum insertion stroke of the external rod 10 is precisely controlled, avoiding the external rod 10 from being over-inserted, which would cause the guide tube 2, the sensor body 1 to make hard contact with the bottom of the deep hole and be damaged. At the same time, it prevents the guide tube 2 from not being able to completely detach from the drill sleeve 11 constraint and the torsion spring from not being able to release its elastic force properly, ensuring that the guide tube 2 unfolds stably. When the sensor body 1 is used in conjunction with it, there is no need to make too many requirements on the structure of the drill sleeve 11 and the external rod 10. It is only necessary to set the limiting block 13 on the external rod 10.

[0039] In another embodiment, when the tension spring 7 is in its normal state, it pulls the sensor body 1 toward the inside of the guide tube 2, causing the sensing end to retract inside the guide tube 2.

[0040] Normal retraction protection prevents damage to the sensor's sensing end when not in detection mode: Under normal conditions, the tension spring 7 retracts the sensing end into the guide tube 2, effectively isolating it from friction and collision with impurities such as soil, gravel, and dead roots. It also prevents damp soil from eroding the sensing end electrode, making it suitable for scenarios with high gravel content and damp soil in Masson pine plantations, significantly extending the sensor's service life. After detection, the slide 4 releases the compression engagement with the extrusion protrusion 12, and the tension spring 7 can quickly pull the sensor body 1 back into the guide tube 2 without manual intervention. Simultaneously, it rotates and retracts into the drill sleeve 11, improving work efficiency. Automatic retraction is achieved solely through the normal elasticity of the tension spring 7, eliminating the need for complex drive structures such as motors and cylinders, ensuring a smooth and controllable detection process.

[0041] In another embodiment, the linear slide 6 extends axially along the guide tube 2, and the axial movement stroke of the slide block 4 along the linear slide 6 is consistent with the extension stroke of the sensing end of the sensor body 1.

[0042] The linear groove 6 extends axially along the guide tube 2, providing precise guidance and limiting for the slide block 4. This effectively prevents the slide block 4 from shifting, jamming, or getting stuck during movement, ensuring that the sliding sleeve 3 and the sensor body 1 can move smoothly along the axial direction of the guide tube 2. This prevents the sensor sensing end from shifting, which could lead to a deviation in the detection position and ensures the accuracy of the fit with the soil inside the deep hole. The travel of the slide block 4 is constrained by the length of the tension spring and is consistent with the extension travel of the sensor sensing end. This allows for precise control of the extension distance of the sensor sensing end, ensuring that the sensing end presses precisely against the inner wall of the deep hole after it extends.

[0043] In another embodiment, the sensor body 1, the sliding sleeve 3, the guide tube 2, the slide block 4 and the tension spring 7 together constitute a retractable protective sensor assembly, and the mounting hole 8, the hinge shaft, the torsion spring and the external rod 10 together constitute an unfolding and retracting drive mechanism. The sensor assembly is an innovative extension of the sensor body 1, and the unfolding and retracting drive mechanism serves the convenience of using the sensor body 1 for soil depth detection.

[0044] The above orientation references do not represent the specific orientations of each component in this implementation scheme. This implementation scheme is only for the convenience of describing the scheme and to make relative descriptions based on the orientations referenced. In reality, the specific orientations of each component are based on their actual installation and use, as well as the orientation descriptions that are customary to those skilled in the art. This is hereby stated.

[0045] The specific embodiments described above further illustrate the inventive purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the scope of protection of the present invention. In particular, it should be noted that any modifications, equivalent substitutions, or improvements made by those skilled in the art within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A soil nutrient monitoring sensor for plantations, characterized in that, The sensor includes a sensor body (1), a guide tube (2) is sleeved on the outside of the sensor body (1), and the sensing end of the sensor body (1) can extend to the outside of the guide tube (2); a sliding sleeve (3) is fixedly connected to the outer wall of the non-sensing end of the sensor body (1), and the sliding sleeve (3) slides in cooperation with the inner wall of the guide tube (2); a straight groove (6) is opened on the guide tube (2), and a sliding seat (4) is fixedly connected to the outer wall of the sliding sleeve (3). The sliding seat (4) passes through the straight groove (6) and extends to the radially outer side of the guide tube (2). An inclined pressing part (5) is formed at the outer end of the sliding seat (4). The inclined surface extends downward toward the non-sensing end of the sensor body (1); a tension spring (7) is provided inside the guide tube (2), one end of the tension spring (7) is connected to the non-sensing end of the sensor body (1), and the other end is connected to the end of the cavity of the guide tube (2); an assembly hole (8) is provided at the end of the guide tube (2) away from the sensing end of the sensor body (1), and the assembly hole (8) is used to rotate and connect with the torsion spring hinge (9) on the external rod (10), so that the guide tube (2) can rotate and switch between the retracted parallel position and the detection unfolded position relative to the external rod (10) under the action of the torsion spring hinge (9); When the guide tube (2) enters the external drill sleeve (11) along with the external rod (10) and is constrained by the drill sleeve (11), the guide tube (2) is in a retracted state parallel to the external rod (10). The tension spring (7) pulls the sensor body (1) into the guide tube (2) for protection. When the guide tube (2) extends out of the drill sleeve (11) along with the external rod (10) and is released from constraint, the guide tube (2) rotates to an unfolded state at a set angle with the external rod (10) under the action of the torsion spring hinge (9). The inclined pressing part (5) of the slide (4) is pressed by the pressing protrusion (12) at the lower end of the drill sleeve (11), driving the slide (4) and the slide sleeve (3) to drive the sensor body (1) to extend in a straight line relative to the guide tube (2), so that the sensing end of the sensor body (1) presses against the inner wall of the soil to achieve detection.

2. The plantation forest soil nutrient monitoring sensor according to claim 1, characterized in that, The structure of the torsion spring hinge shaft (9) is as follows: the guide tube (2) and the external rod (10) are connected by a hinge shaft, and a torsion spring is sleeved on the hinge shaft. One free end of the torsion spring is abutted and connected to the rotating end of the guide tube (2), and the other free end is abutted and connected to the external rod (10).

3. The plantation forest soil nutrient monitoring sensor according to claim 2, characterized in that, When the guide tube (2) is in the unfolded position, it is set perpendicular or approximately perpendicular to the external rod (10).

4. The plantation soil nutrient monitoring sensor according to claim 3, characterized in that, The external rod (10) is a damping rod, and a damping sleeve (14) is fixed inside the drill sleeve (11) to form a damping sliding fit with the external rod (10). The lower end of the drill sleeve (11) is provided with a pressing protrusion (12) for cooperating with the inclined pressing part (5). The pressing protrusion (12) is circular or arc-shaped.

5. The plantation soil nutrient monitoring sensor according to claim 4, characterized in that, The top end of the external rod (10) extends to the outside of the top end of the drill sleeve (11), and a limiting block (13) is fixedly connected to the external rod (10) at a position outside the top end of the drill sleeve (11).

6. The plantation soil nutrient monitoring sensor according to claim 5, characterized in that, When the tension spring (7) is in its normal state, it pulls the sensor body (1) into the guide tube (2), causing the sensing end of the sensor body (1) to retract into the guide tube (2).

7. The plantation soil nutrient monitoring sensor according to claim 6, characterized in that, The linear slide (6) extends axially along the guide tube (2), and the axial movement of the slide block (4) along the linear slide (6) is consistent with the extension stroke of the sensing end of the sensor body (1).

8. A soil nutrient monitoring sensor for plantations according to claim 7, characterized in that, The sensor body (1), sliding sleeve (3), guide tube (2), sliding base (4) and tension spring (7) together constitute a retractable protective sensing component, and the mounting hole (8), hinge shaft, torsion spring and external rod (10) together constitute an unfolding and storage drive mechanism.

Images