Tree diameter at breast height measuring device
The tree diameter at breast height measurement device, which combines an infrared rangefinder and a camera, solves the problems of high labor costs and large errors in traditional measurement methods, realizes continuous measurement and accurate data recording without human intervention, and intuitively reflects the growth status of trees.
Patent Information
- Application Number
- CN202521840869.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-08-28
- Publication Date
- 2025-10-14
- Estimated Expiration
- 2035-08-28
AI Technical Summary
Traditional tree diameter at breast height measurement methods rely on manual operation, resulting in high labor costs, susceptibility to errors, difficulty in achieving continuous data collection and dynamic monitoring, and may interfere with tree growth.
A tree diameter at breast height measurement device was designed, which combines an infrared rangefinder and a camera to achieve non-contact measurement and automatic recording. The device is stable through a reinforcement mechanism, and the connection mechanism adapts to the thickness of trees of different sizes, reducing manual intervention.
It achieves continuous measurement without human intervention, reduces errors, ensures data accuracy and continuity, avoids interference with tree growth, and intuitively reflects growth trends.
Smart Images
Figure CN223435549U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to the field of measurement technology, concretely to a tree breast height diameter measuring device. BACKGROUND
[0002] In the forestry resource investigation, tree growth monitoring and ecological research field, the tree breast height diameter is the core index reflecting the tree growth state and evaluating the forest productivity, and accurately obtaining the breast height diameter data has important significance for grasping the forest growth law and formulating the forestry management strategy, however, the current mainstream tree breast height diameter measurement means still mainly relies on the traditional tool manual measurement, and there is obvious application limitation.
[0003] In the traditional measurement tool, the tape measure, the diameter ruler and the like rely on manual operation, and the staff needs to arrive at the measurement site regularly, and reads the value by directly contacting the trunk, this mode not only consumes a large amount of labor cost, and the measurement result is easily affected by the human operation error, and the precision stability is difficult to guarantee. More importantly, for the long-term dynamic monitoring scene, such as the growth tracking in the nursery growing period and the annual growth evaluation of the rare tree species, the manual measurement needs frequent intervention, cannot realize the continuous data acquisition, and may disturb the tree growth environment due to multiple contacts, at present, the data obtained by the traditional measurement mode mainly relies on the manual recording and arrangement, is easy to appear the data omission or recording error, and it is difficult to dynamically measure the distance of the tree breast height diameter to intuitively reflect the tree growth trend, and needs to be further improved. UTILITY MODEL CONTENT
[0004] The utility model aims at providing a tree breast height diameter measuring device, which has the advantages of dynamic distance measurement and automatic recording and storage of data for the tree breast height diameter, and solves the problems in the prior art.
[0005] In order to achieve the above-mentioned purpose, the utility model provides the following technical scheme:
[0006] A tree breast height diameter measuring device, comprising a bearing mechanism, a first vertical rod fixed to the upper end of the bearing mechanism, a first fixed block fixed to the side wall of the first vertical rod, a connecting mechanism fixed to the end of the first fixed block away from the first vertical rod and a first L-shaped ruler fixed to the connecting mechanism, and scales are arranged on both sides of the first L-shaped ruler;
[0007] The end portions of the two first L-shaped rulers close to each other are fixed with clamping blocks;
[0008] The first vertical rod is externally provided with two second vertical rods, the lower end of the second vertical rod is provided with a lower reinforcing mechanism, the upper end of the two second vertical rods is commonly provided with an upper reinforcing mechanism, the side wall of the second vertical rod is fixed with a fourth fixed block, and the end of the fourth fixed block close to the first vertical rod is fixed with a camera for photographing the scales.
[0009] Preferably, the bearing mechanism comprises a bearing block fixed to the lower end of the first vertical rod, a first bottom block fixed to the lower end of the bearing block, and L-shaped blocks fixed to the two sides of the first bottom block, the right angle edges of the L-shaped blocks being rounded.
[0010] It is worth noting that the combination of the bearing block, the first bottom block and the L-shaped blocks can provide stable bottom support for the first vertical rod of the entire device, so that the device is not easy to shake during measurement. Moreover, the right angle edges of the L-shaped blocks are rounded, which can avoid the edges being too sharp and reduce the risk of scratching the operator during transportation or use, thereby improving the safety of the device.
[0011] Preferably, the lower reinforcing mechanism comprises a second bottom block fixed to the lower end of the second vertical rod, and ground nails inserted through the four corner edges of the upper end of the second bottom block.
[0012] It is worth noting that the second bottom block can increase the contact area between the second vertical rod and the ground, thereby enhancing the stability of the bottom of the second vertical rod. The ground nails are arranged advantageously, which can firmly fix the second vertical rod to the ground by inserting the ground nails into the ground, thereby effectively preventing the second vertical rod from tilting or shifting due to external forces (such as wind blowing or slight collision) during measurement, and achieving the effect of stable reinforcement of the bottom of the second vertical rod.
[0013] Preferably, the upper reinforcing mechanism comprises bearing rings fixed to the side walls of the second vertical rod, a sleeve block placed on the upper ends of the two bearing rings, and nuts screwed to the side walls of the upper end of the second vertical rod, the lower ends of the bearing rings being fixed to the upper ends of the fourth fixed blocks.
[0014] It is worth noting that the bearing rings provide a support point for the placement of the sleeve block, which can connect the two second vertical rods at the top. During use, the sleeve block can be tightly pressed on the bearing rings by the extrusion of the nuts, thereby causing the two second vertical rods to be mutually restrained at the top, avoiding the shaking of the second vertical rods at the top, and achieving the effect of reinforcing the upper parts of the two second vertical rods, thereby ensuring the stability of the second vertical rods as a whole.
[0015] Preferably, the connecting mechanism comprises a horizontal rod fixed to the two sides of the first fixed block, a second fixed block fixed to the end of the horizontal rod away from the first fixed block, a limiting hole provided in the end of the second fixed block away from the first fixed block, a limiting column slidingly arranged in the inner wall of the limiting hole, a connecting block fixed to the end of the limiting column away from the first fixed block, a spring fixed to the end of the connecting block close to the first fixed block, a fixed ring fixed to the end of the spring close to the first fixed block, the end of the fixed ring close to the first fixed block and the end of the second fixed block away from the first fixed block being fixed, and the connecting block and the first L-shaped ruler being fixed to each other.
[0016] It is worth noting that: when the above connecting mechanism is used, the tree can be clamped between the two clamping blocks, when the clamping block of the first L-shaped ruler contacts the tree, the spring can be stretched according to the thickness of the tree, and the limiting column is driven to slide in the limiting hole, so that the clamping block can better fit the surface of the tree, and the adaptive clamping of different thicknesses of trees is realized, and the good contact between the first L-shaped ruler and the tree during measurement is ensured.
[0017] Preferably, the connecting mechanism is a cross block, and the two sides of the first fixed block are fixedly connected with the cross block, and the cross block and the first L-shaped ruler are fixedly connected with each other.
[0018] It is worth noting that: the cross block has simple structure, and is convenient to manufacture and install, and has the advantages that the first L-shaped ruler can be provided with stable connection support, and the position of the first L-shaped ruler is not easy to deviate during measurement.
[0019] Preferably, the first L-shaped ruler is provided with a reinforcing mechanism, the reinforcing mechanism comprises a reinforcing block fixedly connected with the first L-shaped ruler and a second L-shaped ruler fixedly connected with the reinforcing block, and the second L-shaped ruler and the first L-shaped ruler are of the same structure.
[0020] It is worth noting that: the second L-shaped ruler cooperates with the first L-shaped ruler to enhance the strength of the overall structure, so that the measurement structure is more stable during contact with the tree and measurement, and the deformation caused by insufficient structural strength of the measurement structure is reduced.
[0021] Preferably, the first L-shaped ruler, the reinforcing block and the second L-shaped ruler form an integrated structure, and the bottom surface of the integrated structure is U-shaped, and the ends of the two second L-shaped rulers close to each other are fixedly connected with the ends of the two clamping blocks away from each other, and the design of the bottom surface of the U-shaped can better surround the tree, and the connection of the clamping block and the second L-shaped ruler makes the fixation of the clamping block more firm, and the clamping block is not easy to fall off or shift during clamping the tree.
[0022] Preferably, the third fixed block is fixedly connected with the third fixed block on the side wall of the first vertical rod, and the third fixed block is fixedly connected with the infrared distance meter at the end close to the clamping block.
[0023] It is worth noting that: the infrared distance meter can cooperate with the measurement of the scale of the first L-shaped ruler and the recording of the camera, so as to improve the accuracy of measurement, and the non-contact measurement of the infrared distance meter can detect the growth of the tree, for example, when the device is initially installed, the infrared distance meter measures the initial distance of the tree, and after the tree grows, the distance measured by the infrared distance meter decreases, which proves that the tree increases.
[0024] Compared with the prior art, the present application has the following advantages:
[0025] The utility model discloses a bearing mechanism, first vertical rod, first fixed block, connecting mechanism, first L shape ruler, reinforcing block, second L shape ruler, clamping block, third fixed block, infrared range finder, second vertical rod, second bottom block, ground nail, scale through setting down reinforcing mechanism and upper reinforcing mechanism, and the second vertical rod is fixed through down reinforcing mechanism (second bottom block, ground nail) and upper reinforcing mechanism (bearing ring, cover block, nut), and the camera can continuously shoot first L shape ruler scale, and manual field reading is not needed, and manpower investment can be reduced, and the spring of connecting mechanism drives the sliding of the limiting column, and the clamping block can be closely attached to the tree trunk, and the corresponding stability of scale can be ensured, and the camera data of infrared range finder is mutually verified, and manual reading error can be avoided, and the bearing mechanism can stably support first L shape ruler long-term symmetrical placement, and the clamping block is driven to change scale when the tree grows, and manual contact is not needed, and continuous monitoring can be realized and does not disturb the tree, and the camera automatically records scale change, and manual recording error can be avoided, and scale change and the ranging data of infrared range finder are combined, and the diameter growth trend can be more directly reflected. BRIEF DESCRIPTION OF DRAWINGS
[0026] Figure 1 It is whole structural drawing of the utility model;
[0027] Figure 2 It is the three-dimensional structure schematic diagram of infrared range finder of the utility model;
[0028] Figure 3 It is the three-dimensional structure schematic diagram of upper reinforcing mechanism of the utility model;
[0029] Figure 4 It is the three-dimensional structure schematic diagram of down reinforcing mechanism of the utility model;
[0030] Figure 5 It is the three-dimensional split structure schematic diagram of the first embodiment of connecting mechanism of the utility model;
[0031] Figure 6 It is the three-dimensional structure schematic diagram of the second embodiment of connecting mechanism of the utility model;
[0032] Figure 7 It is the schematic diagram of measurement of the utility model.
[0033] Sign significance: 1, bearing mechanism;101, first bottom block;102, bearing block;103, L-shaped block;2, first vertical rod;3, first fixed block;4, connecting mechanism;401, cross rod;402, second fixed block;403, limiting hole;404, limiting column;405, connecting block;406, spring;407, fixed ring;408, cross block;5, first L shape ruler;6, reinforcing block;7, second L shape ruler;8, clamping block;9, third fixed block;10, infrared range finder;11, second vertical rod;1101, bearing ring;1102, cover block;1103, nut;12, fourth fixed block;13, camera;14, second bottom block;15, ground nail;16, scale. DETAILED DESCRIPTION
[0034] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all the other embodiments obtained by those skilled in the art without creative work fall within the scope of the present application.
[0035] In order to solve the problem that the data obtained by the traditional measurement method in the prior art is dependent on manual recording and sorting, data omission or recording errors are prone to occur, and it is difficult to dynamically measure the distance of the tree diameter to intuitively reflect the growth trend of the tree, the following technical scheme is given, please refer to Figures 1-6 ;
[0036] A tree diameter measuring device comprises a bearing mechanism 1, a first vertical rod 2 fixed to the upper end of the bearing mechanism 1, a first fixed block 3 fixed to the side wall of the first vertical rod 2, a connecting mechanism 4 fixed to the end of the first fixed block 3 away from the first vertical rod 2, and a first L-shaped ruler 5 fixed to the connecting mechanism 4, and the first L-shaped ruler 5 is provided with scales 16 on both sides.
[0037] The end portions of the two first L-shaped rulers 5 close to each other are fixed with clamping blocks 8.
[0038] The first vertical rod 2 is externally provided with two second vertical rods 11, the lower end of the second vertical rod 11 is provided with a lower reinforcing mechanism, the upper end of the two second vertical rods 11 is commonly provided with an upper reinforcing mechanism, the side wall of the second vertical rod 11 is fixed with a fourth fixed block 12, and the end of the fourth fixed block 12 close to the first vertical rod 2 is fixed with a camera 13 for photographing the scales 16.
[0039] In use, by placing the bearing mechanism 1 beside the tree, so that the two first L-shaped rulers 5 are located on both sides of the tree, the lower reinforcing mechanism is installed beside the bearing mechanism, so that the camera 13 can record the scale 16 on the first L-shaped ruler 5, the scale 16 adopts millimeter counting, and the scales 16 corresponding to the ends of the two first L-shaped rulers 5 close to each other are 0 scales, the 0 scales gradually increase away from each other along the horizontal direction. When measuring, first, the scales 16 on the two first L-shaped rulers 5 in the initial state are recorded respectively. Specifically, the scale 16 corresponding to the numerical value L1 on one of the first L-shaped rulers 5 is recorded, and the scale 16 corresponding to the numerical value L2 on the other first L-shaped ruler 5 is recorded. When the tree grows, the scales 16 corresponding to the side wall of the tree will change. The scale 16 corresponding to the numerical value L3 on one of the first L-shaped rulers 5 is recorded, and the scale 16 corresponding to the numerical value L4 on the other first L-shaped ruler 5 is recorded. The formula (L3+L4)-(L1+L2) can be used to obtain the numerical value of the change of the tree. In this way, the change of the diameter of the tree after growth can be quickly judged. The distance L5 of the ends of the two first L-shaped rulers 5 close to each other is fixed. When measuring for the first time, (L1+L2+L5) can be used to quickly obtain the diameter of the tree.
[0040] In the embodiment, specifically, the bearing mechanism 1 comprises a bearing block 102 fixed to the lower end of the first vertical rod 2, a first bottom block 101 fixed to the lower end of the bearing block 102, and L-shaped blocks 103 fixed to both sides of the first bottom block 101. The right angle edges of the L-shaped blocks 103 are rounded.
[0041] In the embodiment, specifically, the lower reinforcing mechanism comprises a second bottom block 14 fixed to the lower end of the second vertical rod 11, and ground nails 15 inserted through the four corner edges of the upper end of the second bottom block 14.
[0042] In the embodiment, specifically, the upper reinforcing mechanism comprises a bearing ring 1101 fixed to the side wall of the second vertical rod 11, a sleeve block 1102 placed on the upper end of the two bearing rings 1101, and a nut 1103 screwed to the side wall of the upper end of the second vertical rod 11. The lower end of the bearing ring 1101 is fixed to the upper end of the fourth fixed block 12.
[0043] In the embodiment, specifically: the connecting mechanism 4 comprises a cross rod 401 fixed to the two sides of the first fixed block 3, the end of the cross rod 401 away from the first fixed block 3 is fixed with a second fixed block 402, the end of the second fixed block 402 away from the first fixed block 3 is provided with a limiting hole 403, the inner wall of the limiting hole 403 is slidably provided with a limiting column 404, the end of the limiting column 404 away from the first fixed block 3 is fixed with a connecting block 405, the end of the connecting block 405 close to the first fixed block 3 is fixed with a spring 406, the end of the spring 406 close to the first fixed block 3 is fixed with a fixed ring 407, the end of the fixed ring 407 close to the first fixed block 3 and the end of the second fixed block 402 away from the first fixed block 3 are fixed, and the connecting block 405 and the first L-shaped ruler 5 are fixed with each other, which has the advantages that the expansion and contraction of the spring 406 can drive the limiting column 404 to slide in the limiting hole 403, the clamping block 8 at the end of the first L-shaped ruler 5 can adapt to trees of different thicknesses and closely fit, the good contact between the first L-shaped ruler 5 and the tree during measurement is guaranteed, and the measurement applicability and accuracy are improved.
[0044] In the embodiment, specifically: the connecting mechanism 4 is a cross block 408, the two sides of the first fixed block 3 are fixed with the cross block 408, and the cross block 408 and the first L-shaped ruler 5 are fixed with each other, which has the advantages that the cross block 408 is simple in structure, convenient to manufacture and install, can provide stable connecting support for the first L-shaped ruler 5, effectively reduces the position deviation of the first L-shaped ruler 5 during the measurement process, and guarantees the measurement stability.
[0045] A reinforcing mechanism is arranged on the first L-shaped ruler 5, the reinforcing mechanism comprises a reinforcing block 6 fixed to the first L-shaped ruler 5 and a second L-shaped ruler 7 fixed to the reinforcing block 6, the second L-shaped ruler 7 and the first L-shaped ruler 5 are of the same structure, the first L-shaped ruler 5, the reinforcing block 6 and the second L-shaped ruler 7 form an integrated structure, the bottom surface of the integrated structure is U-shaped, and the ends of the two second L-shaped rulers 7 close to each other are fixed to the ends of the two clamping blocks 8 away from each other, which has the advantages that the integrated structure can enhance the overall strength and reduce the deformation of the first L-shaped ruler 5 and the second L-shaped ruler 7 caused by stress; the U-shaped bottom surface design can better surround the tree, and the connection between the clamping block 8 and the second L-shaped ruler 7 makes the clamping block 8 more firmly fixed, avoiding falling off or displacement during clamping.
[0046] The side wall of the first vertical rod 2 is fixed with a third fixed block 9, the third fixed block 9 is located above the first fixed block 3, and the end of the third fixed block 9 close to the clamping block 8 is fixed with an infrared range finder 10, which has the advantages that the infrared range finder 10 can form data comparison with the scale 16 measurement of the first L-shaped ruler 5 and the camera recording of the camera 13, and mutual verification can be carried out to improve the measurement accuracy; at the same time, the non-contact measurement of the infrared range finder 10 can detect the growth of the tree, and combined with other data, the growth trend of the tree diameter can be intuitively reflected.
[0047] Working principle: when in use, first place the bearing mechanism 1 beside the tree, the first bottom block 101 of the bearing mechanism 1 provides bottom support, the L-shaped block 103 enhances the stability of placement, and the two first L-shaped rulers 5 are symmetrically distributed with the tree as the center. At this time, the clamping block 8 at the end of the first L-shaped ruler 5 is in contact with the side wall of the tree;
[0048] Then place the two second vertical rods 11 outside the first vertical rod 2, increase the contact area with the ground through the second bottom block 14 of the lower reinforcing mechanism, and then insert the ground nail 15 through the second bottom block 14 into the ground to fix the lower end of the second vertical rod 11;
[0049] Then perform the upper reinforcing operation. Since the bearing ring 1101 is fixed to the side wall of the second vertical rod 11 and the lower end is fixed to the upper end of the fourth fixed block 12, first place the sleeve block 1102 on the upper end of the two bearing rings 1101, then thread the nut 1103 onto the upper end of the second vertical rod 11 and tighten it. Through the extrusion of the nut 1103 on the sleeve block 1102, the sleeve block 1102 is tightly pressed on the bearing ring 1101, thereby reinforcing the upper part of the two second vertical rods 11 and ensuring the overall stability of the second vertical rod 11, and further making the camera 13 on the fourth fixed block 12 accurately align with the scale 16 of the first L-shaped ruler 5;
[0050] In the initial measurement, the camera 13 records the scale 16 on the two first L-shaped rulers 5 in the initial state respectively;
[0051] If the connecting mechanism 4 of embodiment 1 is used, the horizontal rod 401 supports the second fixed block 402, and the spring 406 drives the limiting column 404 to slide in the limiting hole 403, so that the clamping block 8 tightly fits the tree;
[0052] If the connecting mechanism 4 of embodiment 2 is used, the horizontal block 408 stably connects the first fixed block 3 and the first L-shaped ruler 5, ensuring the stability of the position of the first L-shaped ruler 5;
[0053] In addition, a reinforcing mechanism can also be installed on the first L-shaped ruler 5. The U-shaped integrated structure of the first L-shaped ruler 5, the reinforcing block 6 and the second L-shaped ruler 7 will enhance the overall stability, and can avoid displacement of the clamping block 8;
[0054] If the infrared range finder 10 is equipped, it will be fixed on the first vertical rod 2 through the third fixed block 9 and record the initial distance from the tree simultaneously. When the device is initially installed, the infrared range finder 10 measures the initial distance of the tree. After the tree grows, the distance measured by the infrared range finder 10 will decrease, which proves that the tree has grown;
[0055] Specifically, the value L1 corresponding to the scale 16 on one of the first L-shaped rulers 5 is recorded, and the value L2 corresponding to the scale 16 on the other first L-shaped ruler 5 is recorded. When the tree grows, the scale 16 corresponding to the side wall of the tree changes. The value L3 corresponding to the scale 16 on one of the first L-shaped rulers 5 is recorded, and the value L4 corresponding to the scale 16 on the other first L-shaped ruler 5 is recorded. The value of the change of the tree can be obtained by using the formula (L3+L4)-(L1+L2), so that the change of the diameter of the breast diameter of the tree after growth can be quickly judged. The distance L5 of the two first L-shaped rulers 5 close to each other is fixed. When measuring for the first time, the diameter of the tree can be quickly obtained by (L1+L2+L5).
[0056] If the connecting mechanism 4 of embodiment 1 is used, when the tree grows, the trunk will push the clamping block 8 to drive the first L-shaped ruler 5 to move, so that the scale 16 on the first L-shaped ruler 5 facing the camera 13 changes. The camera 13 records the changed scale 16, and compares it with the scale 16 on the first L-shaped ruler 5 recorded in the initial state. The growth length of the breast diameter of the tree can be obtained. The distance measured by the infrared range finder 10 also changes accordingly. By comparing the scale 16 data recorded by the camera 13 and the distance data of the infrared range finder 10 at different periods, the growth of the breast diameter of the tree and the specific diameter can be accurately judged.
[0057] Specifically, the distance measured by the infrared range finder 10 when irradiating the outer wall of the trunk for the first time is L6. After the tree grows, the infrared range finder 10 irradiates the outer wall of the trunk again to measure the distance L7. The growth distance of the tree can be obtained by using the formula L7-L6.
[0058] It should be noted that in this document, relational terms such as first and second and the like can be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Moreover, the terms "comprises", "comprising", or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but can include other elements not expressly listed or inherent to such process, method, article, or apparatus.
[0059] Although the embodiments of the present application have been shown and described, it should be understood by those skilled in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present application.
Claims
1. A tree diameter at breast height measuring device, characterized in that: It comprises a carrying mechanism (1), a first upright pole (2) fixed to the upper end of the carrying mechanism (1), a first fixing block (3) fixed to the side wall of the first upright pole (2), a connecting mechanism (4) fixed to an end of the first fixing block (3) away from the first upright pole (2), and a first L-shaped ruler (5) fixed to the connecting mechanism (4), wherein both sides of the first L-shaped ruler (5) are provided with scales (16); The ends of the two first L-shaped rulers (5) that are close to each other are both fixedly connected with clamping blocks (8); Two second upright poles (11) are provided outside the first upright pole (2), a lower reinforcement mechanism is provided at the lower end of the second upright pole (11), an upper reinforcement mechanism is provided on both second upright poles (11), a fourth fixing block (12) is fixedly connected to the side wall of the second upright pole (11), and a camera (13) for photographing the scale (16) is fixedly connected to one end of the fourth fixing block (12) close to the first upright pole (2).
2. A tree diameter at breast height measuring device according to claim 1, characterized in that: The bearing mechanism (1) comprises a bearing block (102) fixed to the lower end of the first upright (2), a first bottom block (101) fixed to the lower end of the bearing block (102), and L-shaped blocks (103) fixed to both sides of the first bottom block (101), wherein the right-angled sides of the L-shaped block (103) are rounded.
3. The tree diameter at breast height measuring device according to claim 1, characterized in that: The lower reinforcement mechanism comprises a second bottom block (14) fixedly connected to the lower end of the second upright pole (11), and ground nails (15) are inserted through the four corner edges of the upper end of the second bottom block (14).
4. The tree diameter at breast height measuring device according to claim 1, characterized in that: The upper reinforcement mechanism comprises a bearing ring (1101) fixedly connected to the side wall of the second upright pole (11), a sleeve block (1102) placed on the upper ends of the two bearing rings (1101), and a nut (1103) threadedly mounted on the side wall of the upper end of the second upright pole (11); the lower end of the bearing ring (1101) is fixedly connected to the upper end of the fourth fixing block (12).
5. The tree diameter at breast height measuring device according to claim 1, characterized in that: The connecting mechanism (4) comprises a cross bar (401) fixed to both sides of the first fixed block (3); the end of the cross bar (401) away from the first fixed block (3) is fixed to the second fixed block (402); the end of the second fixed block (402) away from the first fixed block (3) is provided with a limiting hole (403); the inner wall of the limiting hole (403) is provided with a limiting column (404) for sliding; the end of the limiting column (404) away from the first fixed block (3) is fixed to the connecting block (405); the end of the connecting block (405) close to the first fixed block (3) is fixed to a spring (406); the end of the spring (406) close to the first fixed block (3) is fixed to a fixing ring (407); the end of the fixing ring (407) close to the first fixed block (3) is fixed to the end of the second fixed block (402) away from the first fixed block (3); the connecting block (405) and the first L-shaped ruler (5) are fixed to each other.
6. The tree diameter at breast height measuring device according to claim 1, characterized in that: The connecting mechanism (4) is a transverse block (408), and the transverse blocks (408) are fixedly connected to both sides of the first fixed block (3). The transverse block (408) and the first L-shaped ruler (5) are fixedly connected to each other.
7. The tree diameter at breast height measuring device according to claim 1, characterized in that: The first L-shaped ruler (5) is provided with a reinforcement mechanism, which comprises a reinforcement block (6) fixedly connected to the first L-shaped ruler (5) and a second L-shaped ruler (7) fixedly connected to the reinforcement block (6), wherein the second L-shaped ruler (7) and the first L-shaped ruler (5) have the same structure.
8. The tree diameter at breast height measuring device according to claim 7, characterized in that: The first L-shaped ruler (5), the reinforcement block (6) and the second L-shaped ruler (7) form an integrated structure, and the top surface of the integrated structure is U-shaped. The ends of the two second L-shaped rulers (7) that are close to each other are respectively fixedly connected to the ends of the two clamping blocks (8) that are away from each other.
9. The tree diameter at breast height measuring device according to claim 1, characterized in that: A third fixed block (9) is fixedly connected to the side wall of the first upright pole (2), the third fixed block (9) is located above the first fixed block (3), and an infrared rangefinder (10) is fixedly connected to one end of the third fixed block (9) close to the clamping block (8).