Measuring ring for forest diameter growth monitoring

Abstract

The invention relates to the technical field of measuring tools, and discloses a measuring ring for forest diameter growth monitoring, which comprises a measuring rod, one end of the measuring rod is provided with a U-shaped rod, and two ends of the U-shaped rod are movably connected with sealing rods. According to the measuring ring for forest tree diameter growth monitoring, a trunk to be measured extrudes a sealing rod, the sealing rod rotates around a first rotating shaft, the trunk to be measured penetrates into a U-shaped rod, then a measuring rod is pulled, the trunk to be measured extrudes the sealing rod from the inner side of the U-shaped rod, the sealing rod rotates around a second rotating shaft, and the trunk to be measured penetrates out of the U-shaped rod and is surrounded by a measuring rope; the circumference of the to-be-measured trunk is obtained by reading the scale change of the measuring rope at the position of the pointer before and after measurement, the diameter of the to-be-measured trunk can be further calculated, operation is easy and convenient, and the measuring device can be used for measuring the diameter of the trunk which is not prone to being directly measured at a high position.

Description

Technical Field

[0001] The invention relates to the technical field of measuring tools, and in particular to a measuring ring for monitoring the growth of tree diameters. Background Art

[0002] The tree diameter growth monitoring device is a device specifically used to measure and record changes in tree diameter. This device is often used in forestry research, ecological monitoring and forest management to help scientists and managers understand the growth of trees and the health of forest ecosystems.

[0003] Patent publication number CN102494602A discloses an automatic tree diameter measuring device, including a device fixing module and a measuring module; the device fixing module fixes the measuring module at a position on a tree trunk where the circumference of the tree diameter needs to be measured; the measuring module includes a linear displacement sensor with a spring; the circumference of the tree trunk is measured according to the displacement of the linear displacement sensor with a spring, and the automatic tree diameter measuring device is suitable for research on artificial forest monitoring, plant growth measurement and growth rules.

[0004] The prior art has the following defects:

[0005] The device uses electrical components, which are relatively expensive. In addition, the test device is located outdoors for a long time and is prone to aging and damage. At the same time, the test device needs to be installed manually and can only be installed on lower tree trunks, so it cannot measure the diameter of trees at higher places.

[0006] Measuring the diameter of a tree trunk at a height is necessary in some cases, especially in the following situations:

[0007] Tree morphology research: Measuring the trunk diameter at different heights can help researchers understand the growth pattern and morphological characteristics of trees. The changes in trunk diameter at different heights can reflect the growth strategy and environmental adaptability of trees;

[0008] Biomass estimation: In order to accurately estimate the biomass and carbon storage of individual trees or entire forests, it is necessary to measure the trunk diameter at different heights. These data can be used to build trunk shape models (such as taper equations) to more accurately estimate the overall volume and biomass of trees;

[0009] Tree health monitoring: In some cases, changes in trunk diameter may reflect changes in tree health. By measuring trunk diameter at different heights, a more complete picture of tree growth dynamics and potential health issues can be obtained.

[0010] However, measuring the diameter of a tree trunk at a high altitude is usually more complicated and difficult than measuring the diameter at breast height, and often requires specialized equipment (such as laser rangefinders, tree crown detectors, etc.) or technology (such as remote sensing technology) to complete. Therefore, a device for measuring high trees is needed to simplify the operation and reduce the cost of detection. Summary of the invention

[0011] In view of the above problems in the prior art, a measuring ring for monitoring the diameter growth of trees is proposed.

[0012] The present application provides a measuring ring for monitoring the growth of tree diameters, the purpose of which is to provide a tree diameter measuring device that is simple to operate, simple in structure, and low in price, and can conveniently measure the diameters of trees at high places.

[0013] The technical solution of the present invention is: a measuring ring for monitoring the growth of tree diameters, comprising a measuring rod, one end of the measuring rod is provided with a U-shaped rod, and the other end is provided with a handle, the U-shaped rod comprises a long side and a short side, the end of the short side is provided with a groove 1, the bottom of the groove 1 is provided with a rotating shaft 1, the long side is provided with a groove 2, the bottom of the groove 2 is provided with a rotating shaft 2, the opening of the groove 1 is parallel to the short side, and the opening of the groove 2 points to the bottom of the U-shaped rod, the pair of closing rods are respectively fixed on both sides of the rotating shaft 1 and the rotating shaft 2, a magnetic ball 1 is provided between the right ends of the pair of closing rods, and the bottom of the magnetic ball 1 A second magnetic ball is provided and the second magnetic ball is connected to the short side of the U-shaped rod, a through hole is provided on the second magnetic ball, the first magnetic ball and the second magnetic ball attract each other, a support shaft is provided in the handle, a rope winding wheel is provided on the support shaft, a clockwork spring is provided between the support shaft and the rope winding wheel, a measuring rope is connected to the first magnetic ball, the measuring rope passes through the through hole on the second magnetic ball, and is inserted into the measuring rod close to the short side of the U-shaped rod, the other end of the measuring rope is wound around the rope winding wheel, a window is provided on the measuring rod near the handle, an indicator needle is provided at the window, the indicator needle is perpendicular to the measuring rope, and a scale is provided on the measuring rope.

[0014] By adopting the above scheme, the trunk to be measured is squeezed with the closing rod, so that the closing rod rotates around the first rotation axis, and the trunk to be measured is passed into the U-shaped rod. Then the measuring rod is pulled, so that the trunk to be measured squeezes the closing rod from the inside of the U-shaped rod, and the closing rod rotates around the second rotation axis, so that the trunk to be measured is passed outside the U-shaped rod and surrounded by the measuring rope, and the measuring rope is surrounded by the outer circumference of the trunk to be measured. By reading the scale change of the measuring rope at the indicator needle before and after the measurement, the circumference of the trunk to be measured is obtained, and then the diameter of the trunk to be measured can be calculated. The operation is simple and can be used to measure the diameter of the trunk that is difficult to measure directly at a high place.

[0015] Furthermore, a ring is provided on the outer sleeve of the rotating shaft 1, and the ring slides in the groove 2. A torsion spring is provided between the rotating shaft 1 and the ring. A clamping portion is provided on the outer wall of the ring, and a clamping groove is provided at the bottom of the groove 2, and the clamping portion and the clamping groove cooperate with each other.

[0016] By adopting the above scheme, a torsion spring is set so that the closing rod can be quickly reset after being squeezed by the trunk to be tested and rotated along the second rotating shaft, so that the first magnetic ball and the second magnetic ball are tightly attached together, and the measuring rope is tightly around the trunk, thereby reducing the test error.

[0017] Furthermore, a plug-in hole is provided on the magnetic ball, a plug-in portion is provided in the plug-in hole, and the measuring rope is connected to the plug-in portion.

[0018] By adopting the above scheme, a plug-in part is provided so that the measuring rope is plugged into the plug-in hole through the plug-in part and connected to the magnetic ball. After the test is completed, the measuring rod is pulled hard, the plug-in part is loosened from the plug-in hole, and the measuring rope is released from the encirclement of the tree trunk to be measured, which is convenient for measuring multiple tree trunks.

[0019] Furthermore, the edge of the rope winding wheel is provided with a toothed edge, a pin rod is slidably provided in the handle parallel to the direction of the supporting axis, and the pin rod is provided with engaging teeth, which cooperate with the toothed edge.

[0020] By adopting the above scheme, the locking state of the engaging teeth and the toothed edge is controlled by adjusting the sliding position of the pin rod, thereby controlling the recovery state of the measuring rope.

[0021] Furthermore, the direction of the plug hole is 45° below the horizontal center of the first magnetic ball, and the direction of the through hole is 45° above the horizontal center of the second magnetic ball.

[0022] By adopting the above scheme, the plug hole and the through hole are arranged obliquely, so that the measuring rope can surround the tree trunk to be measured to the utmost extent, thereby reducing the error of the measured value.

[0023] Furthermore, the measuring rod is a telescopic rod, including an outer rod and an inner rod, the outer rod is sleeved on the inner rod, and the telescopic length of the outer rod and the inner rod is adjusted by an elastic protrusion.

[0024] By adopting the above scheme, the testing device can measure the trunk diameters of trees at different heights by adjusting the length of the telescopic rod.

[0025] Furthermore, a plurality of rope-threading ears are provided on the short sides of the U-shaped rod, and the measuring rope passes through the rope-threading ears.

[0026] By adopting the above solution, a plurality of rope-threading ears are provided so that the measuring rope can be arranged close to the U-shaped rod, thereby reducing the error caused by the change of the sliding trajectory of the measuring rope.

[0027] Furthermore, a connecting portion is provided at the bottom of the U-shaped rod, and the U-shaped rod is connected to the measuring rod via the connecting portion.

[0028] By adopting the above solution, the U-shaped rod and the measuring rod bracket can be installed and disassembled through the connecting part.

[0029] Beneficial effects of the present invention:

[0030] 1. The trunk to be measured is squeezed with the closing rod, so that the closing rod rotates around the first axis, and the trunk to be measured is inserted into the U-shaped rod. Then the measuring rod is pulled, so that the trunk to be measured squeezes the closing rod from the inside of the U-shaped rod, and the closing rod rotates around the second axis, so that the trunk to be measured is inserted outside the U-shaped rod and surrounded by the measuring rope, and the measuring rope is surrounded by the outer circumference of the trunk to be measured. By reading the scale change of the measuring rope at the indicator needle before and after the measurement, the circumference of the trunk to be measured is obtained, and then the diameter of the trunk to be measured can be calculated. The operation is simple and can be used to measure the diameter of the trunk that is difficult to measure directly at a high place.

[0031] 2. By setting a torsion spring, the closing rod can be quickly reset after being squeezed by the trunk to be tested and rotated along the second rotating shaft, so that the magnetic ball one and the magnetic ball two are closely attached together, and the measuring rope is tightly around the trunk, thereby reducing the error of the test.

[0032] 3. By setting the plug-in part, the measuring rope is plugged into the plug-in hole and connected to the magnetic ball. After the test is completed, pull the measuring rod hard, the plug-in part is loosened from the plug-in hole, and the measuring rope is released from the trunk to be measured, which is convenient for measuring multiple trunks.

[0033] 4. By setting the plug-in hole and the through hole at an angle, the measuring rope can surround the tree trunk to be measured to the maximum extent, reducing the error of the measured value. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 A three-dimensional diagram of a measuring ring for monitoring the growth of tree diameters according to the present invention;

[0035] Figure 2 For the present invention Figure 1 Enlarged view of the middle U-shaped rod part;

[0036] Figure 3 For the present invention Figure 2 An enlarged diagram of the middle grip;

[0037] Figure 4 It is a side view of the measuring ring for monitoring the growth of tree diameters of the present invention;

[0038] Figure 5 For the present invention Figure 4 Sectional view at AA;

[0039] Figure 6 For the present invention Figure 5Enlarged view of the middle U-shaped rod part;

[0040] Figure 7 For the present invention Figure 5 Enlarged view of the middle grip;

[0041] Figure 8 An exploded view of the U-shaped rod portion of the measuring ring for monitoring the growth of tree diameters of the present invention;

[0042] Fig. 9 For the present invention Figure 8 Other perspectives of view;

[0043] Fig.10 This is a diagram showing the internal structure of the handle in the measuring ring for monitoring the growth of tree diameters of the present invention;

[0044] Fig.11 It is a schematic diagram of step 1 of the method for using the measuring ring for monitoring the growth of tree diameters of the present invention;

[0045] Fig.12 This is a schematic diagram of step 2 of the method for using the measuring ring for monitoring the growth of tree diameters of the present invention;

[0046] Fig.13 This is a schematic diagram of step six of the method for using the measuring ring for monitoring tree diameter growth of the present invention.

[0047] In the figure:

[0048] 1. Measuring rod; 2. U-shaped rod; 3. Grip; 4. Groove 1; 5. Rotating shaft 1; 6. Groove 2; 7. Rotating shaft 2; 8. Closing rod; 9. Magnetic ball 1; 10. Magnetic ball 2; 11. Through hole; 12. Support shaft; 13. Rope winding wheel; 14. Spring; 15. Measuring rope; 16. Window; 17. Indicator needle; 18. Ring; 19. Torsion spring; 20. Engaging part; 21. Engaging groove; 22. Plug-in hole; 23. Plug-in part; 24. Toothed edge; 25. Pin rod; 26. Engaging teeth; 27. Inner rod; 28. Outer rod; 29. ​​Elastic protrusion; 30. Rope threading ear; 31. Connecting part; 32. Tree trunk to be measured. DETAILED DESCRIPTION

[0049] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings.

[0050] Example 1, reference Figure 1-Figure 13, which is the first embodiment of the present invention, provides a measuring ring for monitoring the growth of forest tree diameters, including a measuring rod 1, a U-shaped rod 2 is arranged at one end of the measuring rod 1, and a grip 3 is arranged at the other end, the U-shaped rod 2 includes a long side and a short side, a groove 1 4 is arranged at the end of the short side, a rotating shaft 1 5 is arranged at the bottom of the groove 1 4, a groove 2 6 is arranged on the long side, a rotating shaft 2 7 is arranged at the bottom of the groove 2 6, an opening of the groove 1 4 is parallel to the short side, and an opening of the groove 2 6 points to the bottom of the U-shaped rod 2, a pair of closing rods 8 are respectively fixed on both sides of the rotating shaft 1 5 and the rotating shaft 2 7, a magnetic ball 1 9 is arranged between the right ends of the pair of closing rods 8, a magnetic ball 2 10 is arranged below the magnetic ball 1 9, and the magnetic ball 2 10 It is connected to the short side of the U-shaped rod 2, a through hole 11 is provided on the magnetic ball 10, the magnetic ball 19 and the magnetic ball 10 attract each other, a support shaft 12 is provided in the handle 3, a rope winding wheel 13 is provided on the support shaft 12, a clockwork spring 14 is provided between the support shaft 12 and the rope winding wheel 13, a measuring rope 15 is connected to the magnetic ball 19, the measuring rope 15 passes through the through hole 11 on the magnetic ball 10, and is inserted into the measuring rod 1 close to the short side of the U-shaped rod 2, the other end of the measuring rope 15 is wound around the rope winding wheel 13, a window 16 is provided near the handle 3 of the measuring rod 1, an indicator needle 17 is provided at the window 16, the indicator needle 17 is perpendicular to the measuring rope 15, and a scale is provided on the measuring rope 15.

[0051] Specifically, the shape of the groove 26 fits the rotation trajectory of the rotating shaft 27 when the closing rod 8 rotates around the rotating shaft 15. When the U-shaped rod 2 is set with one long and one short, when the long side of the U-shaped rod 2 is placed on the trunk 32 to be measured, the measuring rod 1 is pushed toward the trunk direction when in use, so that the closing rod 8 is squeezed by the trunk 32 to be measured and rotates around the rotating shaft 15, so that the trunk 32 to be measured is inserted into the U-shaped rod 2, and then the measuring rod 1 is pulled back, so that the closing rod 8 is squeezed by the trunk 32 to be measured and rotates around the rotating shaft 27, so that the trunk 32 to be measured passes out of the U-shaped rod 2 and is tangent to the magnetic ball 19 and the magnetic ball 210. During the tightening process of the measuring rope 15, the length of the trunk 32 to be measured surrounded by the measuring rope 15 is the diameter of the trunk 32 to be measured.

[0052] The trunk 32 to be measured is squeezed by the closing rod 8 to rotate around the rotation axis 1 5, so that the trunk 32 to be measured is inserted into the U-shaped rod 2, and then the measuring rod 1 is pulled to make the trunk 32 to be measured squeeze the closing rod 8 from the inside of the U-shaped rod 2, so that the closing rod 8 rotates around the rotation axis 2 7, so that the trunk 32 to be measured is inserted outside the U-shaped rod 2 and surrounded by the measuring rope 15, and the measuring rope 15 is used to surround the outer periphery of the trunk 32 to be measured. By reading the scale change of the measuring rope 15 at the indicator needle 17 before and after the measurement, the circumference of the trunk 32 to be measured is obtained, and then the diameter of the trunk 32 to be measured is calculated. The operation is simple and can be used to measure the diameter of the trunk that is difficult to measure directly at a high place.

[0053] Reference Figure 6A sleeve 18 is disposed on the outer sleeve of the rotating shaft 5, and the sleeve 18 slides in the groove 2 6. A torsion spring 19 is disposed between the rotating shaft 5 and the sleeve 18. A clamping portion 20 is disposed on the outer wall of the sleeve 18, and a clamping groove 21 is disposed at the bottom of the groove 2 6. The clamping portion 20 and the clamping groove 21 cooperate with each other.

[0054] Specifically, when the engaging portion 20 is engaged in the engaging groove 21, the closing rod 8 is squeezed from the inside of the U-shaped rod 2 to the outside, and the closing rod 8 is subjected to the force of the torsion spring 19 so that the rotating shaft 5 tends to approach the groove 4. When the rotating shaft 5 approaches the groove 4, the magnetic ball 9 and the magnetic ball 2 10 will be adsorbed together, and the engaging portion 20 is tangent to the sliding trajectory of the ring 18 in the groove 6. Therefore, the engaging portion 20 will not affect the sliding of the ring 18 in the groove 6. Only when the engaging portion 20 and the engaging groove 21 are engaged, the rotation of the ring 18 is restricted.

[0055] By setting the torsion spring 19, the closing rod 8 can be quickly reset after being squeezed by the trunk 32 to be tested and rotated along the second shaft 7, so that the magnetic ball 1 9 and the magnetic ball 2 10 are closely attached together, and the measuring rope 15 is tightly around the trunk, reducing the test error.

[0056] Reference Figure 6 The magnetic ball 9 is provided with an inserting hole 22 , a plugging portion 23 is provided in the inserting hole 22 , and the measuring rope 15 is connected to the plugging portion 23 .

[0057] Specifically, the plug-in portion 23 is conical, and a wedge-shaped protrusion is provided on the conical wall. When the plug-in portion 23 is inserted into the plug-in hole 22 , it can withstand a certain pulling force. When the pulling force is large, the plug-in portion 23 is separated from the plug-in hole 22 .

[0058] By setting the plug-in part 23, the measuring rope 15 is plugged into the plug-in hole 22 through the plug-in part 23 and connected to the magnetic ball 9. After the test is completed, the measuring rod 1 is pulled hard, the plug-in part 23 is loosened from the plug-in hole 22, and the measuring rope 15 is released from the trunk 32 to be measured, so that it is convenient to measure multiple trunks.

[0059] Reference Fig.10 The edge of the rope wheel 13 is provided with a toothed edge 24 , and a pin rod 25 is slidably provided in the handle 3 parallel to the direction of the support shaft 12 , and a locking tooth 26 is provided on the pin rod 25 , and the locking tooth 26 cooperates with the toothed edge 24 .

[0060] Specifically, limited ends are provided at both ends of the pin rod 25, and the cross-section of the pin rod 25 is square. When the pin rod 25 slides until the engaging teeth 26 engage with the toothed edge 24, the rotation of the rope winding wheel 13 is locked; when the pin rod 25 slides until the engaging teeth 26 and the toothed edge 24 are misaligned, the rope winding wheel 13 is free to rotate, and the measuring rope 15 is always in a tendency to rewind.

[0061] The locking state of the engaging teeth 26 and the toothed edge 24 is controlled by adjusting the sliding position of the pin 25 , thereby controlling the recovery state of the measuring rope 15 .

[0062] Reference Figure 6 The direction of the plug hole 22 is 45° below the horizontal center of the magnetic ball 9, and the direction of the through hole 11 is 45° above the horizontal center of the magnetic ball 10.

[0063] Specifically, even if the plug hole 22 and the through hole 11 are set at an angle, there is still a slight distance error between the two ends of the measuring rope 15 passing through the plug hole 22 and the through hole 11. This error can be avoided by adding a fixed value compensation value when reading.

[0064] By arranging the plug hole 22 and the through hole 11 obliquely, the measuring rope 15 can surround the tree trunk 32 to be measured to the maximum extent, thereby reducing the error of the measured value.

[0065] Reference Figure 1 The measuring rod 1 is a telescopic rod, including an outer rod 28 and an inner rod 27 . The outer rod 28 is sleeved on the inner rod 27 . The outer rod 28 and the inner rod 27 are adjusted in telescopic length by an elastic protrusion 29 .

[0066] By adjusting the length of the telescopic rod, the testing device can measure the trunk diameters of trees at different heights.

[0067] Reference Figure 2 A plurality of rope-threading ears 30 are provided on the short side of the U-shaped rod 2 , and the measuring rope 15 passes through the rope-threading ears 30 .

[0068] By providing a plurality of rope-threading ears 30 , the measuring rope 15 is arranged close to the U-shaped rod 2 , thereby reducing the error caused by the change of the sliding track of the measuring rope 15 .

[0069] Reference Figure 2 A connecting portion 31 is provided at the bottom of the U-shaped rod 2 , and the U-shaped rod 2 is connected to the measuring rod 1 through the connecting portion 31 .

[0070] The U-shaped rod 2 and the measuring rod 1 bracket can be assembled and disassembled through the connecting portion 31 .

[0071] Example 2, reference Figure 1-Figure 13 , which is the second embodiment of the present invention, provides a method for using a measuring ring for monitoring the growth of tree diameters, using the measuring ring for monitoring the growth of tree diameters, including the following steps:

[0072] Step 1: Place the long side of the U-shaped rod 2 against the trunk 32 to be measured, so that the trunk 32 to be measured is located at the opening of the U-shaped rod 2, and push the measuring rod 1 toward the trunk, so that the closing rod 8 is squeezed by the trunk 32 to be measured and rotates around the rotating shaft 5, so that the trunk 32 to be measured is inserted into the U-shaped rod 2;

[0073] Step 2: Pull the measuring rod 1 back again, so that the closing rod 8 is squeezed by the trunk 32 to be measured and rotates around the second rotation axis 7, so that the trunk 32 to be measured passes through the U-shaped rod 2, and the measuring rope 15 is in a surplus state;

[0074] Step 3: Adjust the sliding position of the pin 25 to control the locking state of the engaging teeth 26 and the toothed edge 24, and lock the recovery state of the measuring rope 15;

[0075] Step 4: The closing rod 8 is quickly reset after rotating along the rotating shaft 2 7 under the force of the torsion spring 19, so that the magnetic ball 1 9 and the magnetic ball 2 10 are closely attached to each other;

[0076] Step 5: Adjust the sliding position of the pin 25 to release the locking state between the locking teeth 26 and the toothed edge 24, and open the recovery state of the measuring rope 15;

[0077] Step 6: The measuring rope 15 is tightened around the tree trunk 32 to be measured, and the diameter of the tree trunk 32 to be measured is obtained by reading the scale change of the measuring rope 15 at the indicator needle 17 before and after the measurement;

[0078] Step 7: Adjust the sliding position of the pin 25 to control the locking state of the engaging teeth 26 and the toothed edge 24, lock the recovery state of the measuring rope 15, and then pull the measuring rod 1 back, the plug-in portion 23 disengages from the plug-in hole 22, and the measuring rope 15 is released from the encirclement of the tree trunk 32 to be measured.

[0079] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A measuring ring for monitoring tree diameter growth, comprising a measuring rod (1), characterized in that: A U-shaped rod (2) is provided at one end of the measuring rod (1), and a grip (3) is provided at the other end. The U-shaped rod (2) comprises a long side and a short side. A groove (4) is provided at the end of the short side. A rotating shaft (5) is provided at the bottom of the groove (4). A groove (6) is provided on the long side. A rotating shaft (7) is provided at the bottom of the groove (6). The opening of the groove (4) is parallel to the short side, and the opening of the groove (6) points to the bottom of the U-shaped rod (2). The pair of closing rods (8) are respectively fixed on both sides of the rotating shaft (5) and the rotating shaft (7). A magnetic ball (9) is provided between the right ends of the pair of closing rods (8). A magnetic ball (10) is provided below the magnetic ball (9) and is connected to the short side of the U-shaped rod (2). The magnetic ball (10) is provided on the magnetic ball (10). A through hole (11) is provided, the magnetic ball 1 (9) and the magnetic ball 2 (10) attract each other, a support shaft (12) is provided in the handle (3), a rope winding wheel (13) is provided on the support shaft (12), a spring spring (14) is provided between the support shaft (12) and the rope winding wheel (13), a measuring rope (15) is connected to the magnetic ball 1 (9), the measuring rope (15) passes through the through hole (11) on the magnetic ball 2 (10), and is inserted into the measuring rod (1) close to the short side of the U-shaped rod (2), and the other end of the measuring rope (15) is wound around the rope winding wheel (13), and a window (16) is provided on the measuring rod (1) near the handle (3), and an indicator needle (17) is provided at the window (16), and the indicator needle (17) is perpendicular to the measuring rope (15), and a scale is provided on the measuring rope (15).

2. The measuring ring for monitoring tree diameter growth according to claim 1, characterized in that: The outer sleeve of the rotating shaft (5) is provided with a collar (18), and the collar (18) slides in the groove (6). A torsion spring (19) is provided between the rotating shaft (5) and the collar (18). A clamping portion (20) is provided on the outer wall of the collar (18), and a clamping groove (21) is provided at the bottom of the groove (6), and the clamping portion (20) and the clamping groove (21) are matched with each other.

3. The measuring ring for monitoring tree diameter growth according to claim 1, characterized in that: The magnetic ball (9) is provided with an inserting hole (22), a plugging portion (23) is provided in the inserting hole (22), and the measuring rope (15) is connected to the plugging portion (23).

4. The measuring ring for monitoring tree diameter growth according to claim 1, characterized in that: The edge of the rope winding wheel (13) is provided with a toothed edge (24), and a pin rod (25) is slidably provided in the handle (3) parallel to the direction of the support shaft (12), and the pin rod (25) is provided with a snap-fitting tooth (26), and the snap-fitting tooth (26) is matched with the toothed edge (24).

5. The measuring ring for monitoring tree diameter growth according to claim 1, characterized in that: The direction of the plug hole (22) is 45 degrees below the horizontal center of the first magnetic ball (9), and the direction of the through hole (11) is 45 degrees above the horizontal center of the second magnetic ball (10).

6. The measuring ring for monitoring tree diameter growth according to claim 1, characterized in that: The measuring rod (1) is a telescopic rod, comprising an outer rod (28) and an inner rod (27). The outer rod (28) is sleeved on the inner rod (27). The telescopic lengths of the outer rod (28) and the inner rod (27) are adjusted via an elastic protrusion (29).

7. The measuring ring for monitoring tree diameter growth according to claim 1, characterized in that: A plurality of rope-threading ears (30) are arranged on the short sides of the U-shaped rod (2), and the measuring rope (15) passes through the rope-threading ears (30).

8. The measuring ring for monitoring tree diameter growth according to claim 1, characterized in that: A connecting portion (31) is provided at the bottom of the U-shaped rod (2), and the U-shaped rod (2) is connected to the measuring rod (1) via the connecting portion (31).

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